Pharmaceuticals

25 pages, 1988 KiB

Open AccessArticle

Screening of Bacterial Quorum Sensing Inhibitors in a Vibrio fischeri LuxR-Based Synthetic Fluorescent E. coli Biosensor

by Xiaofei Qin, Celina Vila-Sanjurjo, Ratna Singh, Bodo Philipp and Francisco M. Goycoolea

Pharmaceuticals 2020, 13(9), 263; https://doi.org/10.3390/ph13090263 - 22 Sep 2020

Cited by 6 | Viewed by 5331

Abstract

A library of 23 pure compounds of varying structural and chemical characteristics was screened for their quorum sensing (QS) inhibition activity using a synthetic fluorescent Escherichia coli biosensor that incorporates a modified version of lux regulon of Vibrio fischeri. Four such compounds [...] Read more.

A library of 23 pure compounds of varying structural and chemical characteristics was screened for their quorum sensing (QS) inhibition activity using a synthetic fluorescent Escherichia coli biosensor that incorporates a modified version of lux regulon of Vibrio fischeri. Four such compounds exhibited QS inhibition activity without compromising bacterial growth, namely, phenazine carboxylic acid (PCA), 2-heptyl-3-hydroxy-4-quinolone (PQS), 1H-2-methyl-4-quinolone (MOQ) and genipin. When applied at 50 µM, these compounds reduced the QS response of the biosensor to 33.7% ± 2.6%, 43.1% ± 2.7%, 62.2% ± 6.3% and 43.3% ± 1.2%, respectively. A series of compounds only showed activity when tested at higher concentrations. This was the case of caffeine, which, when applied at 1 mM, reduced the QS to 47% ± 4.2%. In turn, capsaicin, caffeic acid phenethyl ester (CAPE), furanone and polygodial exhibited antibacterial activity when applied at 1mM, and reduced the bacterial growth by 12.8% ± 10.1%, 24.4% ± 7.0%, 91.4% ± 7.4% and 97.5% ± 3.8%, respectively. Similarly, we confirmed that trans-cinnamaldehyde and vanillin, when tested at 1 mM, reduced the QS response to 68.3% ± 4.9% and 27.1% ± 7.4%, respectively, though at the expense of concomitantly reducing cell growth by 18.6% ± 2.5% and 16% ± 2.2%, respectively. Two QS natural compounds of Pseudomonas aeruginosa, namely PQS and PCA, and the related, synthetic compounds MOQ, 1H-3-hydroxyl-4-quinolone (HOQ) and 1H-2-methyl-3-hydroxyl-4-quinolone (MHOQ) were used in molecular docking studies with the binding domain of the QS receptor TraR as a target. We offer here a general interpretation of structure-function relationships in this class of compounds that underpins their potential application as alternatives to antibiotics in controlling bacterial virulence. Full article

(This article belongs to the Special Issue Novel Antibacterial Agents)

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Graphical abstract

Graphical abstract
Full article ">Figure 1
Chemical structures of studied compounds. Group (1) lactone analogues, Group (2) aromatic ring structures, Group (3) heterocyclic compounds, Group (4) Pseudomonas spp.-relevant compounds, and Group (5) structurally unrelated compounds. In the Figure are also shown the structure of natural LuxR and TraR ligands, namely 3OC6HSL and OOHL. Other details of the series of compounds are given in Materials and Methods section. Full article ">Figure 1 Cont.
Chemical structures of studied compounds. Group (1) lactone analogues, Group (2) aromatic ring structures, Group (3) heterocyclic compounds, Group (4) Pseudomonas spp.-relevant compounds, and Group (5) structurally unrelated compounds. In the Figure are also shown the structure of natural LuxR and TraR ligands, namely 3OC6HSL and OOHL. Other details of the series of compounds are given in Materials and Methods section. Full article ">Figure 2
Effect of increasing concentrations of gardenoside, caffeine and furanone on the fluorescence (a–c), growth (d–f) and density-normalised fluorescence (g–i) of the E. coli biosensor over time. The three compounds are chosen as representatives of the following categories: no inhibition (gardenoside; a,d,g), QS inhibition in the absence of growth reduction (caffeine; b,e,h) and QS and growth inhibition (furanone; c,f,i). Results from additional experiments on other compounds are available in <a href="#app1-pharmaceuticals-13-00263" class="html-app">Supporting Information</a>. Data shows the mean and standard deviation of a representative experiment with triplicated treatments. Full article ">Figure 3
End-point effect of the 23 candidate compounds on the QS-based response and growth of the E. coli biosensor. (a) Effect of compounds 10, 2, 9, 3, 1, 7, 8, 13, 21, 5, 11, 6, 4, 22; applied at 1 × 10−3 M on the density-normalised fluorescence of treated cells relative to control cells. Relative fluorescence was calculated as follows: the mean of the last ten values of density-normalised fluorescence over time, corresponding to 246–300 min of incubation (see <a href="#pharmaceuticals-13-00263-f002" class="html-fig">Figure 2</a>) was divided by the corresponding values of untreated cells. (b) Effect of compounds 10, 2, 9, 3, 1, 7, 8, 13, 21, 5, 11, 6, 4, 22; applied at 1 × 10−3 M on cell density of treated cells relative to control cells. Relative OD600 was calculated as follows: the mean of the last 10 OD600 values over time, corresponding to 246–300 min of incubation (see <a href="#pharmaceuticals-13-00263-f002" class="html-fig">Figure 2</a>) was divided by the corresponding values of untreated cells. (c). Effect of compounds 21, 17, 16, 23, 19, 14, 12, 15, 18, 20; applied at 5 × 10−5 M on the density-normalised fluorescence of treated cells relative to control cells. Relative fluorescence was calculated as in (a,d) Effect of compounds 21, 17, 16, 23, 19, 14, 12, 15, 18, 20; applied at 5 × 10−5 M on cell density of treated cells relative to control cells. Relative OD600 was calculated as in (b) t-Student statistical comparisons were made using itaconic acid as a reference treatment (* p < 0.05, ** p < 0.01, *** p < 0.001 and **** p < 0.0001). Data show the mean and standard deviation of three independent experiments with triplicated treatments. Full article ">Figure 4
(a) GRID-MIFs for TraR protein with DRY probe (green) showing favorable hydrophobic interaction sites. GRID-MIFs for TraR protein with HD (blue) and HA (red) probes showing favorable hydrogen bond (blue for hydrogen bond donor and red for hydrogen bond acceptor) binding sites. (b) Natural substrate OOHL. Full article ">Figure 5
Interaction of TraR receptor with (a) OOHL; (b) PCA, (c) and (d) PQS; (e) MOQ; (f) HOQ and (g) MHOQ. (c) shows us the PQS conf A and (d) shows PQS conf B. Close-up view of all compounds binding site, oxygen carbon and nitrogen are colored in red yellow and blue, respectively, hydrogen bonds are shown as blue line. Full article ">

25 pages, 1514 KiB

Open AccessArticle

Fragaria viridis Fruit Metabolites: Variation of LC-MS Profile and Antioxidant Potential during Ripening and Storage

by Daniil N. Olennikov, Aina G. Vasilieva and Nadezhda K. Chirikova

Pharmaceuticals 2020, 13(9), 262; https://doi.org/10.3390/ph13090262 - 22 Sep 2020

Cited by 28 | Viewed by 4759

Abstract

Fragaria viridis Weston or creamy strawberry is one of the less-known species of the Fragaria genus (Rosaceae family) with a wide distribution in Eurasia and is still in the shadow of more popular relatives F. ananassa (garden strawberry) or F. vesca (wild strawberry). [...] Read more.

Fragaria viridis Weston or creamy strawberry is one of the less-known species of the Fragaria genus (Rosaceae family) with a wide distribution in Eurasia and is still in the shadow of more popular relatives F. ananassa (garden strawberry) or F. vesca (wild strawberry). Importantly, there is a lack of scientific knowledge on F. viridis compounds, their stability in the postharvest period, and bioactivity. In this study, metabolites of F. viridis fruits in three ripening stages were characterized with high-performance liquid chromatography with photodiode array and electrospray ionization triple quadrupole mass spectrometric detection (HPLC-PAD-ESI-tQ-MS). In total, 95 compounds of various groups including carbohydrates, organic acids, phenolics, and triterpenes, were identified for the first time. The quantitative content of the compounds varied differently during the ripening progress; some of them increased (anthocyanins, organic acids, and carbohydrates), while others demonstrated a decrease (ellagitannins, flavonols, etc.). The most abundant secondary metabolites of F. viridis fruits were ellagitannins (5.97–7.54 mg/g of fresh weight), with agrimoniin (1.41–2.63 mg/g) and lambertianin C (1.20–1.86 mg/g) as major components. Antioxidant properties estimated by in vitro assays (2,2-diphenyl-1-picrylhydrazyl radical (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) cation radical (ABTS), ferric reducing antioxidant power (FRAP), and oxygen radical absorbance capacity (ORAC)) showed good antioxidant potential in all ripening stages of F. viridis fruits. The pilot human experiment on the effect of F. viridis fruit consumption on the serum total antioxidant capacity confirmed the effectiveness of this kind of strawberry. Postharvest storage of ripe fruits at 4 °C and 20 °C lead to declining content in the majority of compounds particularly ascorbic acid, ellagitannins, and flavonols, with the most significant loss at room temperature storage. These results suggest that F. viridis fruits are a prospective source of numerous metabolites that have potential health benefits. Full article

(This article belongs to the Special Issue Applications of Liquid Chromatography in Analysis of Pharmaceuticals and Natural Products)

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14 pages, 5383 KiB

Open AccessArticle

Vascular α1A Adrenergic Receptors as a Potential Therapeutic Target for IPAD in Alzheimer’s Disease

by Miles Frost, Abby Keable, Dan Baseley, Amber Sealy, Diana Andreea Zbarcea, Maureen Gatherer, Ho Ming Yuen, Matt MacGregor Sharp, Roy O. Weller, Johannes Attems, Colin Smith, Paul R. Chiarot and Roxana O. Carare

Pharmaceuticals 2020, 13(9), 261; https://doi.org/10.3390/ph13090261 - 22 Sep 2020

Cited by 11 | Viewed by 3498

Abstract

Drainage of interstitial fluid from the brain occurs via the intramural periarterial drainage (IPAD) pathways along the basement membranes of cerebral capillaries and arteries against the direction of blood flow into the brain. The cerebrovascular smooth muscle cells (SMCs) provide the motive force [...] Read more.

Drainage of interstitial fluid from the brain occurs via the intramural periarterial drainage (IPAD) pathways along the basement membranes of cerebral capillaries and arteries against the direction of blood flow into the brain. The cerebrovascular smooth muscle cells (SMCs) provide the motive force for driving IPAD, and their decrease in function may explain the deposition of amyloid-beta as cerebral amyloid angiopathy (CAA), a key feature of Alzheimer’s disease. The α-adrenoceptor subtype α_1A is abundant in the brain, but its distribution in the cerebral vessels is unclear. We analysed cultured human cerebrovascular SMCs and young, old and CAA human brains for (a) the presence of α_1A receptor and (b) the distribution of the α_1A receptor within the cerebral vessels. The α_1A receptor was present on the wall of cerebrovascular SMCs. No significant changes were observed in the vascular expression of the α_1A-adrenergic receptor in young, old and CAA cases. The pattern of vascular staining appeared less punctate and more diffuse with ageing and CAA. Our results show that the α_1A-adrenergic receptor is preserved in cerebral vessels with ageing and in CAA and is expressed on cerebrovascular smooth muscle cells, suggesting that vascular adrenergic receptors may hold potential for therapeutic targeting of IPAD. Full article

(This article belongs to the Special Issue New Drugs and Biologics For Treatment of Central Nervous Dysfunction)

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Figure 1
The pattern of distribution of the α-adrenoceptors alpha1a adrenergic receptor (α1A-AR) in the grey matter of the occipital lobe. Neuronal staining appeared most intense in young cases (A) and decreased in both old (B) and cerebral amyloid angiopathy (CAA) cases (C). In all cases, α1A-AR immunoreactivity was observed in vessel walls (enlarged boxes 1, 2 and 3). There was a significant decrease in α1A-AR in CAA cases compared to young groups (D) and no differences observed in the vessel wall (E). Graphs depict the mean ±95% confidence intervals; n = 5. Scale bar 50 µm. * p < 0.05. Full article ">Figure 2
The pattern of distribution of the α1A-AR in the white matter of the occipital lobe. Neuronal staining appeared most intense in young cases (A) and appeared to decrease in both old (B) and CAA cases (C). In all cases, α1A-AR immunoreactivity was observed in vessel walls (enlarged boxes 1, 2 and 3). There were no significant differences observed in overall percentage area staining (D) or the percentage of the vessel wall positive for α1A-AR in white matter (E). Graphs depict the mean ±95% confidence intervals, n = 5. Scale bar 50 µm. Full article ">Figure 3
The pattern of distribution of the α1A-AR in leptomeningeal vessels of the occipital lobe. In all cases, α1A-AR immunoreactivity was observed in vessel walls (A, B and C and enlarged boxes 1, 2 and 3). There were no significant differences in the percentage of the vessel wall positive for α1A-AR between cases (D). Graph depicts the mean ±95% confidence intervals, n = 5. Scale bar 50 µm. Full article ">Figure 4
Immunofluorescence for α1A-AR (green) and Aβ (red) on sections of human occipital cortex of a case of CAA. The green immunofluorescence is present within the endothelium and in between the amyloid deposits of the wall of the vessel. Based on the diameter of the vessel and the thickness of the vessel wall, as well as the presence of CAA mainly in cortical arterioles, the vessels are arterioles of 10 µm diameter. Scale bar 25 µm. (A) immunostaining for Aβ occupying the whole of the vessel wall in a circumferential manner (B) immunostaining for α1A-AR showing a focal distribution; (C) the overlay image of both Aβ and α1A-AR immunofluorescence. Full article ">Figure 5
α1A-AR immunoreactivity in the vessel walls of capillaries, arteries and veins and within cultured human brain vascular smooth muscle cells. α1A-AR immunoreactivity (green) was observed colocalised (white arrows) to lectin (blue) in the vessel walls of capillaries (A–D), arteries (E–H) and veins (I–L) in all cases. α1A-AR immunoreactivity was also colocalised with smooth muscle actin (red) in arterial walls (H) and observed to outline smooth muscle cell bodies in culture (M–O). Scale bar 50 µm. Full article ">

22 pages, 612 KiB

Open AccessReview

Adenosine Signaling in Autoimmune Disorders

by Giulia Magni and Stefania Ceruti

Pharmaceuticals 2020, 13(9), 260; https://doi.org/10.3390/ph13090260 - 22 Sep 2020

Cited by 28 | Viewed by 4161

Abstract

The molecular components of the purinergic system (i.e., receptors, metabolizing enzymes and membrane transporters) are widely expressed in the cells of the immune system. Additionally, high concentrations of adenosine are generated from the hydrolysis of ATP in any “danger” condition, when oxygen and [...] Read more.

The molecular components of the purinergic system (i.e., receptors, metabolizing enzymes and membrane transporters) are widely expressed in the cells of the immune system. Additionally, high concentrations of adenosine are generated from the hydrolysis of ATP in any “danger” condition, when oxygen and energy availability dramatically drops. Therefore, adenosine acts as a retaliatory metabolite to counteract the nucleotide-mediated boost of the immune reaction. Based on this observation, it can be foreseen that the recruitment with selective agonists of the receptors involved in the immunomodulatory effect of adenosine might represent an innovative anti-inflammatory approach with potential exploitation in autoimmune disorders. Quite surprisingly, pro-inflammatory activity exerted by some adenosine receptors has been also identified, thus paving the way for the hypothesis that at least some autoimmune disorders may be caused by a derailment of adenosine signaling. In this review article, we provide a general overview of the roles played by adenosine on immune cells with a specific focus on the development of adenosine-based therapies for autoimmune disorders, as demonstrated by the exciting data from concluded and ongoing clinical trials. Full article

(This article belongs to the Special Issue Adenosine Receptors as Attractive Targets in Human Diseases)

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Graphical abstract

9 pages, 4650 KiB

Open AccessCommunication

Molecular Features of Non-Selective Small Molecule Antagonists of the Bradykinin Receptors

by Bahareh Rasaeifar, Patricia Gomez-Gutierrez and Juan J. Perez

Pharmaceuticals 2020, 13(9), 259; https://doi.org/10.3390/ph13090259 - 21 Sep 2020

Cited by 12 | Viewed by 4216

Abstract

Angiotensin converting enzyme 2 (ACE2) downregulation is a key negative factor for the severity of lung edema and acute lung failure observed in patients infected with SARS-CoV-2. ACE2 downregulation affects the levels of diverse peptide mediators of the renin-agiotensin-aldestosterone and kallikrein-kinin systems, compromising [...] Read more.

Angiotensin converting enzyme 2 (ACE2) downregulation is a key negative factor for the severity of lung edema and acute lung failure observed in patients infected with SARS-CoV-2. ACE2 downregulation affects the levels of diverse peptide mediators of the renin-agiotensin-aldestosterone and kallikrein-kinin systems, compromising vascular hemostasis. Increasing evidence suggests that the inflammatory response observed in covid-19 patients is initiated by the action of kinins on the bradykinin receptors. Accordingly, the use of bradykinin antagonists should be considered as a strategy for therapeutic intervention against covid-19 illness progression. Presently, icatibant is the only bradykinin antagonist drug approved. In the present report, we investigated the molecular features characterizing non-selective antagonists targeting the bradykinin receptors and carried out a in silico screening of approved drugs, aimed at the identification of compounds with a non-selective bradykinin antagonist profile that can be evaluated for drug repurposing. The study permitted to identify eight compounds as prospective non-selective antagonists of the bradykinin receptors, including raloxifene; sildenafil; cefepime; cefpirome; imatinib; ponatinib; abemaciclib and entrectinib. Full article

(This article belongs to the Special Issue Kinins and Their Receptors as Potential Therapeutic Targets —— A Tribute to Professor Domenico Regoli, A Key Figure in the Field of Kinins)

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Figure 1

Figure 1
Crosstalk between RAAS and KKS. The angiotensin converting enzymes ACE and ACE2 are key players of RAAS, regulating the production of diverse mediators (see text), producing a plethora of physiological actions through the activation of different receptors (solid arrows). Thus, activation of the angiotensin AT1 receptor produces vasoconstriction, hypertrophy and fibrosis; whereas activation of the AT2 and Mas receptors produce vasodilation, antihypertrophy and antifibrosis. On the other hand, ACE regulates the levels of kinins that produce vasodilatation and increased vascular permeability through the B1 and B2 receptors. Full article ">Figure 2
Chemical structure of icatibant, together with its residue sequence. Hyp=hydroxylproline; Thi = thiophenyl-alanine; Tic = 1,2,3,4-tetrahydroisoquinolin-2-ylcarbonyl; Oic = (3aS,7aS)-octahydroindol-2-ylcarbonyl. Full article ">Figure 3
Superposition of the B1 and B2 receptor pharmacophores. Colored spheres represent pharmacophore points (P1–P5) according to the following color code: dark blue represents a positive charge moiety; magenta a hydrogen bond accepting center; light blue a hydrogen bond donor/acceptor center; green an aromatic/lipophilic center. @B1 and @B2 is used to differentiate P5 for the B1 and B2 receptors, respectively. Consensus distances between common pharmacophore points are (black dotted lines): d(1,2) = 9 Å; d(1,3) = 14 Å; d(1,4) = 10.5 Å; d(2,3) = 6 Å; d(2,4) = 7 Å; d(3,4) = 7.5 Å. Specific distances for the B1 pharmacophore: d(1,5) = 9.5 Å; d(2,5) = 9.3 Å; d(3,5) = 9.5 Å; d(4,5) = 5.7 Å; whereas for the B2 pharmacophore are (orange dotted lines): d(1,5) = 11 Å; d(2,5) = 9 Å; d(3,5) = 8.8 Å; d(4,5) = 8.4 Å. Side chains of the main residues involved in defining the binding pocket for non-peptide ligands are explicitly depicted: green for the B1 and blue for the B2, respectively. Full article ">Figure 4
Chemical structures of the eight compounds identified by virtual screening of the DrugBank database. Color dots are drawn on top of the moieties responsible for fulfilling pharmacophore points P1–P4 according to the color code described in <a href="#pharmaceuticals-13-00259-f001" class="html-fig">Figure 1</a>. Full article ">

12 pages, 555 KiB

Open AccessArticle

Tisagenlecleucel in Children and Young Adults: Reverse Translational Research by Using Real-World Safety Data

by Concetta Rafaniello, Carmen Ferrajolo, Mario Gaio, Alessia Zinzi, Cristina Scavone, Maria Giuseppa Sullo, Francesco Rossi, Liberato Berrino and Annalisa Capuano

Pharmaceuticals 2020, 13(9), 258; https://doi.org/10.3390/ph13090258 - 21 Sep 2020

Cited by 9 | Viewed by 3108

Abstract

Tisagenlecleucel has revolutionized the pharmacological approach of relapsed or refractory B-cell acute lymphoblastic leukaemialeukaemia in paediatrics. The safety profile of tisagenlecleucel still needs to be better defined. The aim of this study was a post-marketing evaluation of the safety of tisagenlecleucel through the [...] Read more.

Tisagenlecleucel has revolutionized the pharmacological approach of relapsed or refractory B-cell acute lymphoblastic leukaemialeukaemia in paediatrics. The safety profile of tisagenlecleucel still needs to be better defined. The aim of this study was a post-marketing evaluation of the safety of tisagenlecleucel through the analysis of the Eudravigilance database with focus on the paediatric population. From 2017 to 2020, one third of Individual Case Safety Reports referring to tisagenlecleucel (117/364) have been collected in paediatrics, on average nine year-old boys. Overall, 92% of the638 adverse events were serious and caused or prolonged hospitalisation. A total of 55 adverse events presented a fatal outcome, mainly due to progression of malignant neoplasm (N = 10; 18.2%), recurrence of acute lymphocytic leukaemia (N = 6; 10.9%) or occurrence of acute lymphocytic leukaemia (N = 5; 9.1%). Cytokine release syndrome was commonly reported after tisagenlecleucel infusion (54/638), followed by pyrexia (45/638) and hypotension (27/638). Only 18/638 events referred to neurotoxicity, none of them resulted in death. More than one third of cases (41/117) were suggestive of therapeutic failure. This first post-marketing analysis confirms pre-approval evidence of the safety profile of tisagenlecleucel in paediatrics. Since only a few years of marketing is available, further followed-up studies need to be performed to investigate longer-term safety of tisagenlecleucel. Full article

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9 pages, 648 KiB

Open AccessArticle

Association between Polygenic Risk Score and One-Year Outcomes Following As-Needed Aflibercept Therapy for Exudative Age-Related Macular Degeneration

by Taiyo Shijo, Yoichi Sakurada, Seigo Yoneyama, Wataru Kikushima, Atsushi Sugiyama, Mio Matsubara, Yoshiko Fukuda, Fumihiko Mabuchi and Kenji Kashiwagi

Pharmaceuticals 2020, 13(9), 257; https://doi.org/10.3390/ph13090257 - 20 Sep 2020

Cited by 10 | Viewed by 2690

Abstract

We investigated whether polygenic risk score (PRS) was associated with one-year outcome of as-needed aflibercept therapy for exudative age-related macular degeneration (AMD), including AMD (n = 129) and polypoidal choroidal vasculopathy (n = 132). A total of 261 patients were treated [...] Read more.

We investigated whether polygenic risk score (PRS) was associated with one-year outcome of as-needed aflibercept therapy for exudative age-related macular degeneration (AMD), including AMD (n = 129) and polypoidal choroidal vasculopathy (n = 132). A total of 261 patients were treated with as-needed intravitreal aflibercept injection (IAI) after three monthly IAIs and the completion of a one-year follow-up. One hundred and seventy-two healthy volunteers served as controls. Genotyping of ARMS2 A69S (rs10490924), CFH I62V (rs800292), SKIV2L-C2-CFB (rs429608), C3 (rs2241394), ADAMTS-9 (rs6795735) and CETP (rs3764261) was performed for all participants. A total of 63 PRSs were quantified. There was a positive association between the PRS involving ARMS2, CFH, C3, and ADAMTS-9 and best-corrected visual acuity at twelve months (p = 0.046, multiple regression analysis). When comparing PRSs of patients requiring retreatment and of patients without retreatment, 35 PRSs were significantly greater in patients requiring retreatment than in patients without requiring retreatment, with the PRS involving ARMS2 and CFH being most significantly associated (p = 1.6 × 10⁻⁴). The number of additional injections was significantly associated with 40 PRSs and the PRS involving ARMS2 and CFH showed a most significant p-value (p = 2.42 × 10⁻⁶). Constructing a PRS using a combination with high-risk variants might be informative for predicting the response to IAI for exudative AMD. Full article

(This article belongs to the Special Issue Pharmacotherapy for Macular Diseases)

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17 pages, 2777 KiB

Open AccessArticle

The Basement Membrane in a 3D Breast Acini Model Modulates Delivery and Anti-Proliferative Effects of Liposomal Anthracyclines

by Tabea Wiedenhoeft, Tobias Braun, Ronald Springer, Michael Teske, Erik Noetzel, Rudolf Merkel and Agnes Csiszár

Pharmaceuticals 2020, 13(9), 256; https://doi.org/10.3390/ph13090256 - 19 Sep 2020

Cited by 4 | Viewed by 3127

Abstract

Breast cancer progression is marked by cancer cell invasion and infiltration, which can be closely linked to sites of tumor-connected basement membrane thinning, lesion, or infiltration. Bad treatment prognosis frequently accompanies lack of markers for targeted therapy, which brings traditional chemotherapy into play, [...] Read more.

Breast cancer progression is marked by cancer cell invasion and infiltration, which can be closely linked to sites of tumor-connected basement membrane thinning, lesion, or infiltration. Bad treatment prognosis frequently accompanies lack of markers for targeted therapy, which brings traditional chemotherapy into play, despite its adverse effects like therapy-related toxicities. In the present work, we compared different liposomal formulations for the delivery of two anthracyclines, doxorubicin and aclacinomycin A, to a 2D cell culture and a 3D breast acini model. One formulation was the classical phospholipid liposome with a polyethylene glycol (PEG) layer serving as a stealth coating. The other formulation was fusogenic liposomes, a biocompatible, cationic, three-component system of liposomes able to fuse with the plasma membrane of target cells. For the lysosome entrapment-sensitive doxorubicin, membrane fusion enabled an increased anti-proliferative effect in 2D cell culture by circumventing the endocytic route. In the 3D breast acini model, this process was found to be limited to cells beneath a thinned or compromised basement membrane. In acini with compromised basement membrane, the encapsulation of doxorubicin in fusogenic liposomes increased the anti-proliferative effect of the drug in comparison to a formulation in PEGylated liposomes, while this effect was negligible in the presence of intact basement membranes. Full article

(This article belongs to the Section Pharmaceutical Technology)

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Full article ">Figure 1
Chemical structures of aclacinomycin A (ACL) and doxorubicin (DOX) are shown. ACL has a more complex structure compared to DOX due to the long aglycolic side chain. Full article ">Figure 2
Analysis by fluorescence spectroscopy of the anthracyclines and the membrane tracer dye DiR indicated a spectral overlap of anthracyclines’ fluorescence emission (ACL em. and DOX em.) and DiR excitation (DiR exc.) suitable for Foerster Resonance Energy Transfer (FRET) (A). Fluorescence intensity was normalized with respect to the individual highest fluorescence intensity for better visualization. DiR in the liposomal formulations of FL and PEG-EL showed a noticeable fluorescence emission upon excitation at 633 nm but not at 488 nm in the given experimental setting (B). Data were normalized with respect to the highest fluorescence intensity of DiR emission in FL upon excitation at 633 nm. Incorporation of ACL in FL resulted in possible DiR emission after excitation at 488 nm due to FRET (C). A similar FRET signal was not observed when FL were loaded with DOX (D). In C and D, data were normalized with respect to the highest fluorescence intensity of anthracycline emission in PEG-EL. Data are shown as normalized mean curves; a DiR excitation spectrum is shown representatively. Full article ">Figure 3
Monitoring the cellular uptake of anthracycline-loaded liposomal formulations. Fusion of FL with MCF-10A cell membrane was observed by incorporation of DiR, leading to a homogenous membrane staining not observed after treatment with PEG-EL (A). Incorporation of ACL (FL-ACL) or DOX (FL-DOX) did not affect membrane fusion, yet subcellular localization of ACL and DOX differed after cellular uptake (B). Scale bars 20 µm. Full article ">Figure 4
Anti-proliferative effect of anthracyclines in MCF-10A cells. Investigation of the proliferation of MCF-10A cells by cell count using flow cytometry demonstrated a dose-dependent anti-proliferative effect of both ACL and DOX encapsulated in FL (A). The anti-proliferative effect of ACL and DOX was affected by the formulation, with significantly increasing potency for FL-ACL and FL-DOX in comparison to the free drugs and for FL-DOX in comparison to PEG-EL-DOX in an EdU (5-ethynyl-2′-deoxyuridine) incorporation assay (B). Samples treated with PBS served as a control (CTL). The used doses of ACL and DOX in the EdU incorporation assay were 0.6 µM and 1.8 µM, respectively, and are indicated by red stars in (A). Mean with standard deviation (A) and box plots (B) are shown. Statistical evaluation was done using non-parametrical Kruskal–Wallis test with post-hoc Dunn’s test (*: p < 0.05; ***: p < 0.0005). Full article ">Figure 5
Liposomal uptake into MCF-10A cells in a 3D acini model. Note the high extent and homogeneity of plasma membrane staining with DiR in acini with a lowly developed (ld) basement membrane (BM) (A). The highly developed (hd) BM of MCF-10A acini was imaged by immunofluorescent staining of collagen IV and laminin 332 (B). The relative change of median fluorescence intensity of DiR incorporated in cells cultured in the MCF-10A acini model was investigated using flow cytometry after treatment with FL or PEG-EL (C). A highly developed BM could be degraded by treatment with collagenase IV, as be observed by immunofluorescent staining of collagen IV and laminin 332 (D). Degradation of the BM before treatment with FL led to a relative change of median fluorescence intensity comparable to that of acini having a compromised BM (E). Scale bars 20 µm. Mean with confidence interval (95%) is shown, statistical evaluation was done using one-way ANOVA with post-hoc Tukey’s test (*: p < 0.05; **: p < 0.01). Full article ">Figure 6
Formulation affects potency of DOX depending on the BM status. MCF-10A acini with a lowly developed and compromised BM were treated with ACL and DOX in the liposomal formulations and analyzed by the EdU incorporation assay (A). Quantitative analysis indicated an overall significant reduction of proliferation, except for the treatment with PEG-EL-DOX, with a significantly higher reduction when FL-DOX was compared with PEG-EL-DOX (B). Samples treated with PBS served as a control (CTL). This effect was not found when proliferation was investigated in MCF-10A acini with a highly developed and intact BM (hd; B). Association of the liposome dye DiR with the BM could be shown by immunofluorescent staining of collagen IV after treatment of hd-BM acini with FL (C). Scale bars 20 µm. Box plots are shown, statistical evaluation was done using Kruskal–Wallis test, with post-hoc Dunn’s test (***: p < 0.0005). Full article ">

16 pages, 5265 KiB

Open AccessArticle

Eluxadoline Loaded Solid Lipid Nanoparticles for Improved Colon Targeting in Rat Model of Ulcerative Colitis

by Md. Khalid Anwer, Mohammed Muqtader Ahmed, Mohammed F. Aldawsari, Saad Alshahrani, Farhat Fatima, Mohd Nazam Ansari, Najeeb Ur Rehman and Ramadan I. Al-Shdefat

Pharmaceuticals 2020, 13(9), 255; https://doi.org/10.3390/ph13090255 - 19 Sep 2020

Cited by 18 | Viewed by 3499

Abstract

The aim of the current study was to evaluate the therapeutics potential of eluxadoline (ELX) loaded solid lipid nanoparticles (SLNs) in ulcerative colitis. ELX loaded SLNs were prepared using three different lipids according to the solvent emulsification technique. The optimization of prepared SLNs [...] Read more.

The aim of the current study was to evaluate the therapeutics potential of eluxadoline (ELX) loaded solid lipid nanoparticles (SLNs) in ulcerative colitis. ELX loaded SLNs were prepared using three different lipids according to the solvent emulsification technique. The optimization of prepared SLNs (F1-F3) were carried out based on size, PDI, zeta potential, percent drug entrapment (%EE), and loading (%DL). The lipid (stearic acid) based SLNs (F2) was optimized with particle size (266.0 ± 6.4 nm), PDI (0.217 ± 0.04), zeta potential (31.2 ± 5.19 mV), EE (65.0 ± 4.8%), and DL (4.60 ± 0.8%). The optimized SLNs (F2) was further evaluated by DSC, FTIR, SEM, in vitro release, and stability studies, which confirmed the successful encapsulation of ELX in SLNs. The efficacy of optimized SLNs (F2) in comparison to the pure ELX drug was assessed in acetic acid induced colitis rat models. It was observed that the delivery of ELX by SLNs alleviated the induced acetic acid colitis significantly. Thus, ELX loaded SLNs delivery to the colon has a significant potential to be developed for the treatment of ulcerative colitis. Full article

(This article belongs to the Section Medicinal Chemistry)

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20 pages, 2111 KiB

Open AccessArticle

Epigallocatechin-3-Gallate-Loaded Gold Nanoparticles: Preparation and Evaluation of Anticancer Efficacy in Ehrlich Tumor-Bearing Mice

by Mohamed A. Safwat, Bothaina A. Kandil, Mohamed A. Elblbesy, Ghareb M. Soliman and Nermin E. Eleraky

Pharmaceuticals 2020, 13(9), 254; https://doi.org/10.3390/ph13090254 - 18 Sep 2020

Cited by 30 | Viewed by 3860

Abstract

Epigallocatechin-3-gallate (EGCG) is a pleiotropic compound with anticancer, anti-inflammatory, and antioxidant properties. To enhance EGCG anticancer efficacy, it was loaded onto gold nanoparticles (GNPs). EGCG-GNPs were prepared by a simple green synthesis method and were evaluated using different techniques. Hemocompatibility with human blood [...] Read more.

Epigallocatechin-3-gallate (EGCG) is a pleiotropic compound with anticancer, anti-inflammatory, and antioxidant properties. To enhance EGCG anticancer efficacy, it was loaded onto gold nanoparticles (GNPs). EGCG-GNPs were prepared by a simple green synthesis method and were evaluated using different techniques. Hemocompatibility with human blood and in vivo anticancer efficacy in Ehrlich ascites carcinoma-bearing mice were evaluated. EGCG/gold chloride molar ratio had a marked effect on the formation and properties of EGCG-GNPs where well-dispersed spherical nanoparticles were obtained at a molar ratio not more than 0.8:1. The particle size ranged from ~26 to 610 nm. High drug encapsulation efficiency and loading capacity of ~93 and 32%, respectively were obtained. When stored at 4 °C for three months, EGCG-GNPs maintained over 90% of their drug payload and had small changes in their size and zeta potential. They were non-hemolytic and had no deleterious effects on partial thromboplastin time, prothrombin time, and complement protein C3 concentration. EGCG-GNPs had significantly better in vivo anticancer efficacy compared with pristine EGCG as evidenced by smaller tumor volume and weight and higher mice body weight. These results confirm that EGCG-GNPs could serve as an efficient delivery system for EGCG with a good potential to enhance its anticancer efficacy. Full article

(This article belongs to the Special Issue Nanoparticle-Mediated Drug Delivery, Imaging, and Control of Cellular Functions)

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26 pages, 2512 KiB

Open AccessReview

Data-Driven Molecular Dynamics: A Multifaceted Challenge

by Mattia Bernetti, Martina Bertazzo and Matteo Masetti

Pharmaceuticals 2020, 13(9), 253; https://doi.org/10.3390/ph13090253 - 18 Sep 2020

Cited by 27 | Viewed by 5283

Abstract

The big data concept is currently revolutionizing several fields of science including drug discovery and development. While opening up new perspectives for better drug design and related strategies, big data analysis strongly challenges our current ability to manage and exploit an extraordinarily large [...] Read more.

The big data concept is currently revolutionizing several fields of science including drug discovery and development. While opening up new perspectives for better drug design and related strategies, big data analysis strongly challenges our current ability to manage and exploit an extraordinarily large and possibly diverse amount of information. The recent renewal of machine learning (ML)-based algorithms is key in providing the proper framework for addressing this issue. In this respect, the impact on the exploitation of molecular dynamics (MD) simulations, which have recently reached mainstream status in computational drug discovery, can be remarkable. Here, we review the recent progress in the use of ML methods coupled to biomolecular simulations with potentially relevant implications for drug design. Specifically, we show how different ML-based strategies can be applied to the outcome of MD simulations for gaining knowledge and enhancing sampling. Finally, we discuss how intrinsic limitations of MD in accurately modeling biomolecular systems can be alleviated by including information coming from experimental data. Full article

(This article belongs to the Special Issue Computational Drug Discovery and Development in the Era of Big Data)

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Pictorial representation of data exploitation in molecular dynamics (MD) simulations. Note that the source of data can be either computational (the very output of MD simulations, paths “1” and “2”) or experimental (path “3”). Path “1” refers to the use of machine learning (ML) methods for the conventional analysis step performed a posteriori once the MD data have been generated. Path “2” depicts a loop where ML methods enter during the simulations to inform subsequent MD runs (specifically consisting of simulation runs, data generation, and ML-based data analysis). This loop can be either discontinuous (MD/ML resampling) or seamless (on-the-fly MD/ML). Full article ">Figure 2
Pictorial representation of the unsupervised learning class of methods: cluster analysis (panel (A)) and dimensionality reduction (panel (B), principal component analysis (PCA) is displayed as a representative example). Full article ">Figure 3
Schematic representation of the difference between the Euclidean and geodesic distance (green solid and red dashed lines, respectively) evaluated in a curved manifold. The network-based nearest neighbor approximation of the geodesic distance provided by Isomap is also shown (red solid lines). Full article ">Figure 4
Difference between the components extracted through PCA (panel (A)) and a generic independent coordinate analysis (ICA) method (panel (B)). In specific cases, ICA provides a better description of the high-d data structure, as the eigenvectors identified are not necessarily restrained to the orthogonality relationship. Full article ">Figure 5
Schematic representation of an autoencoder. Basing on the conformations sampled through the MD simulations (protein in blue ribbons with surrounding water molecules), a latent space can be learned and trained (blue dots in the bottom plot) in a way to reproduce at best the original input data structure (blurred blue protein on the right). The latent space information can also be used to generate previously unexplored conformations (red dots in the bottom plot and red protein on the right). Full article ">Figure 6
Pictorial representation of supervised learning class of methods: classification (panel (A), linear discriminant analysis (LDA) is displayed as an example) and regression (panel (B), linear regression displayed as an example,). Full article ">Figure 7
Using MD simulations in combination with experimental information. (A) Through a validation procedure, it is possible to estimate the agreement between computed quantities (average observable s, in the figure) and reference experimental data (sexp). (B) Correction of the sampled data through a reweighting procedure can improve the agreement between predicted (MD trajectory) and measured (experiments). (C) Enforcing the experimental information in an on-the-fly fashion, the sampled ensemble is restrained to best match the experimental one. Full article ">

20 pages, 3537 KiB

Open AccessArticle

The Anticancer Activity for the Bumetanide-Based Analogs via Targeting the Tumor-Associated Membrane-Bound Human Carbonic Anhydrase-IX Enzyme

by Azizah M. Malebari, Tarek S. Ibrahim, Ibrahim M. Salem, Ismail Salama, Ahdab N. Khayyat, Samia M. Mostafa, Osama I. El-Sabbagh and Khaled M. Darwish

Pharmaceuticals 2020, 13(9), 252; https://doi.org/10.3390/ph13090252 - 18 Sep 2020

Cited by 21 | Viewed by 3209

Abstract

The membrane-bound human carbonic anhydrase (hCA) IX is widely recognized as a marker of tumor hypoxia and a prognostic factor within several human cancers. Being undetected in most normal tissues, hCA-IX implies the pharmacotherapeutic advent of reduced off-target adverse effects. We assessed the [...] Read more.

The membrane-bound human carbonic anhydrase (hCA) IX is widely recognized as a marker of tumor hypoxia and a prognostic factor within several human cancers. Being undetected in most normal tissues, hCA-IX implies the pharmacotherapeutic advent of reduced off-target adverse effects. We assessed the potential anticancer activity of bumetanide-based analogues to inhibit the hCA-IX enzymatic activity and cell proliferation of two solid cancer cell lines, namely kidney carcinoma (A-498) and bladder squamous cell carcinoma (SCaBER). Bumetanide analogues efficiently inhibit the target hCA-IX in low nanomolar activity (IC₅₀ = 4.4–23.7 nM) and have an excellent selectivity profile (SI = 14.5–804) relative to the ubiquitous hCA-II isoform. Additionally, molecular docking studies provided insights into the compounds’ structure–activity relationship and preferential binding of small-sized as well as selective bulky ligands towards the hCA-IX pocket. In particular, 2,4-dihydro-1,2,4-triazole-3-thione derivative 9c displayed pronounced hCA-IX inhibitory activity and impressive antiproliferative activity on oncogenic A-498 kidney carcinoma cells and is being considered as a promising anticancer candidate. Future studies will aim to optimize this compound to fine-tune its anticancer activity as well as explore its potential through in-vivo preclinical studies. Full article

(This article belongs to the Section Medicinal Chemistry)

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20 pages, 2459 KiB

Open AccessReview

Natural Products: A Potential Source of Malaria Transmission Blocking Drugs?

by Phanankosi Moyo, Grace Mugumbate, Jacobus N. Eloff, Abraham I. Louw, Vinesh J. Maharaj and Lyn-Marié Birkholtz

Pharmaceuticals 2020, 13(9), 251; https://doi.org/10.3390/ph13090251 - 17 Sep 2020

Cited by 17 | Viewed by 4983

Abstract

The ability to block human-to-mosquito and mosquito-to-human transmission of Plasmodium parasites is fundamental to accomplish the ambitious goal of malaria elimination. The WHO currently recommends only primaquine as a transmission-blocking drug but its use is severely restricted by toxicity in some populations. New, [...] Read more.

The ability to block human-to-mosquito and mosquito-to-human transmission of Plasmodium parasites is fundamental to accomplish the ambitious goal of malaria elimination. The WHO currently recommends only primaquine as a transmission-blocking drug but its use is severely restricted by toxicity in some populations. New, safe and clinically effective transmission-blocking drugs therefore need to be discovered. While natural products have been extensively investigated for the development of chemotherapeutic antimalarial agents, their potential use as transmission-blocking drugs is comparatively poorly explored. Here, we provide a comprehensive summary of the activities of natural products (and their derivatives) of plant and microbial origins against sexual stages of Plasmodium parasites and the Anopheles mosquito vector. We identify the prevailing challenges and opportunities and suggest how these can be mitigated and/or exploited in an endeavor to expedite transmission-blocking drug discovery efforts from natural products. Full article

(This article belongs to the Special Issue Natural Compounds as Potential Antimalarial Agents, 2020)

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Full article ">Figure 1
Overview of transmission-blocking assays and natural product origins. (a) Sexual stages within the human host are categorised into early-stage (I–III) and late-stage (IV–V) gametocytes. Gametocytes are sexually dimorphic with both male (micro-) and female (macro-) gametocytes found in human host at a ratio of ~1:3.6, respectively. Inside the mosquitoes’ midgut, micro-gametocytes develop into mature micro-gametes, a process called exflagellation. Each micro-gametocyte produces eight micro-gametes while a macro-gametocyte matures into a single macro-gamete. Gametocyte development into gametes is termed gametogenesis. Micro- and macro-gametes fuse together to form a zygote that develops into a motile ookinete. Gamete-zygote-ookinete development constitute early sporogonic stages (ESS). Ookinetes penetrate the midgut wall where they form oocysts which enlarge over time and eventually rupture to release sporozoites. Different assay platforms to assess the activity against different stages include gametocyte stage specific assays (which assess either development, viability, metabolic or redox status), dual gamete formation assays (DGFA) (examine development of mature gametocytes into either micro- or macro-gametes), ookinete development assay (ODA) (examines development of gametes to ookinetes), standard membrane feeding assay (SMFA, assess either the number of oocysts per mosquito (termed oocyst intensity) or total number of mosquitoes with oocysts (termed oocysts prevalence) and endectocidal assays (which examine insecticidal properties of drugs upon ingestion by mosquito). Numbers indicated in blue and green circles indicate number of pure natural compounds and plant extracts screened per each respective stage. TB–transmission-blocking. (b) Summary of plant species reviewed for activity against transmission-blocking stages. Quite noticeable is the lack of investigations on gametes. It is also evident that the Asteraceae, Meliaceae and Combretaceae are the most investigated plant families with most species from the latter family being inactive against the respective transmission-blocking stages they were interrogated against. The colour scale indicates active (red) and inactive (black) plants species against specific stages. Full article ">Figure 2
Chemical structures of highly potent microbial-derived compounds targeting P. falciparum transmissible stages. Full article ">Figure 3
Chemical structures of selected plant-derived compounds with some described activity (including only moderate) against P. falciparum transmissible stages. * 1α,4α-dihydroxybishopsolicepolide. Full article ">

14 pages, 10261 KiB

Open AccessArticle

Hybrid Multimodal Imaging Synthons for Chemoselective and Efficient Biomolecule Modification with Chelator and Near-Infrared Fluorescent Cyanine Dye

by Ralph Hübner, Valeska von Kiedrowski, Vanessa Benkert, Björn Wängler, Ralf Schirrmacher, Roland Krämer and Carmen Wängler

Pharmaceuticals 2020, 13(9), 250; https://doi.org/10.3390/ph13090250 - 16 Sep 2020

Cited by 7 | Viewed by 3532

Abstract

The development of hybrid multimodal imaging synthons (MIS), carrying in addition to a chelator for radiometal labeling also a near-infrared (NIR) fluorescent cyanine dye was the aim of this work. The MIS should be introducible into biomolecules of choice via an efficient and [...] Read more.

The development of hybrid multimodal imaging synthons (MIS), carrying in addition to a chelator for radiometal labeling also a near-infrared (NIR) fluorescent cyanine dye was the aim of this work. The MIS should be introducible into biomolecules of choice via an efficient and chemoselective click chemistry reaction. After chemical optimization, a successful synthetic strategy towards such hybrid MIS was developed, based on solid phase-based synthesis techniques and applying different near-infrared fluorescent cyanine dyes. The developed hybrid agents were shown to be easily introducible into a model homobivalent peptidic gastrin-releasing peptide receptor- (GRPR)-specific carrier without forming any side products and the MIS as well as their bioconjugates were radiolabeled with the positron-emitter ⁶⁸Ga³⁺. The hybrid multimodal agents were characterized with regard to their log_Ds, GRPR target affinities and photophysical characteristics. It could be shown that the properties of the bioconjugates were not per se affected by the introduction of the MIS but that the cyanine dye used and specifically the number of comprised negative charges per dye molecule can have a considerable influence on target receptor binding. Thus, the molecular toolbox described here enables the synthesis of tailored hybrid multimodal imaging synthons for biomolecule modification, meeting the specific need and envisioned application of the combined imaging agent. Full article

(This article belongs to the Section Radiopharmaceutical Sciences)

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Schematic depiction of the operation principle of combined multimodal positron emission tomography/computed tomography (PET/CT) and near-infrared fluorescence optical imaging (NIR-OI) imaging. The first step is the injection of the multimodal, target-specific imaging agent and whole-body PET/CT imaging (A) followed by the intraoperative NIR-fluorescence optical image-guided surgery where the optically active compound clearly delineates e.g. tumor margins and identifies malignantly transformed lymph nodes (B). Full article ">Figure 2
Structures of the NIR cyanine dyes used in this study: LS277 (1), CK002 (2) and SK015 (3). Full article ">Figure 3
Structures of the chelator- and NIR-fluorescent dye-modified bioconjugates 14–16, the chelator-only analog 17 and 18, lacking both chelator and NIR dye. Full article ">Figure 4
Radio-HPLC chromatograms of [68Ga]Ga-10–[68Ga]Ga-12 and [68Ga]Ga-19 ([68Ga]Ga-10: blue; [68Ga]Ga-11: black; [68Ga]Ga-12: red; [68Ga]Ga-19: green) (A). Radio-HPLC chromatograms of [68Ga]Ga-10–[68Ga]Ga-12 from left to right; black traces: radiolabeling with tris(2-carboxyethyl)phosphine (TCEP), red traces: radiolabeling without TCEP (B–D). Radio-HPLC chromatograms of [68Ga]Ga-14–[68Ga]Ga-17 ([68Ga]Ga-14: black; [68Ga]Ga-15: blue; [68Ga]Ga-16: red; [68Ga]Ga-17: green) (E). Analytical HPLC chromatograms were obtained using a gradient of 0% H2O–100% MeCN (+0.1% trifluoroacetic acid (TFA)) in 5 min. Full article ">Figure 5
Results of the competitive displacement assays of the hybrid multimodal imaging synthon-bioconjugates 14–16, the reference compounds 17 and 18 as well as bombesin (BBN) on stably GRPR-transfected human embryonic kidney 293 (HEK) cells using [125I]I-Tyr4-bombesin as competitor. The 50% inhibitory concentration (IC50) values for BBN (being used as internal standard with known high GRPR affinity) and 14–18 were determined to be 2.81 ± 0.56 nM, 27.39 ± 2.01 nM, 56.07 ± 1.47 nM, 181.23 ± 2.45 nM, 21.48 ± 1.2 nM and 16.64 ± 1.06 nM, respectively (A). Correlation between IC50 values and number of negative charges of 14–18 (B). Full article ">Scheme 1
Schematic depiction of the final synthetic pathway towards the target multimodal imaging synthons (MIS) 10–12. Full article ">

12 pages, 11664 KiB

Open AccessArticle

Impact of Sampling Period on Population Pharmacokinetic Analysis of Antibiotics: Why do You Take Blood Samples Following the Fourth Dose?

by So Won Kim, Dong Jin Kim, Dae Young Zang and Dong-Hwan Lee

Pharmaceuticals 2020, 13(9), 249; https://doi.org/10.3390/ph13090249 - 16 Sep 2020

Cited by 1 | Viewed by 3197

Abstract

To date, many population pharmacokinetic models of antibiotics have been developed using blood sampling data after the fourth or fifth dose, which represents steady-state levels. However, if a model developed using blood sampled after the first dose is equivalent to that using blood [...] Read more.

To date, many population pharmacokinetic models of antibiotics have been developed using blood sampling data after the fourth or fifth dose, which represents steady-state levels. However, if a model developed using blood sampled after the first dose is equivalent to that using blood sampled after the fourth dose, it would be advantageous to utilize the former. The aim of this study was to investigate the effect of blood sampling after the first and/or fourth drug administration on the accuracy and precision of parameter estimates. A previously reported robust, two-compartment model of vancomycin was used for simulation to evaluate the performances of the parameter estimates. The parameter estimation performances were assessed using relative bias and relative root mean square error. Performance was investigated in 72 scenarios consisting of a combination of two blood sampling periods (the first and fourth dose), two total clearances, three infusion times, and four sample sizes. The population pharmacokinetic models from data collected at the first dose and those collected at the fourth dose produced parameter estimates that were similar in accuracy and precision. This study will contribute to increasing the efficiency and simplicity of antibiotic pharmacokinetic studies. Full article

(This article belongs to the Section Pharmacology)

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30 pages, 2056 KiB

Open AccessReview

Current Insights on Antifungal Therapy: Novel Nanotechnology Approaches for Drug Delivery Systems and New Drugs from Natural Sources

by Filipa Sousa, Domingos Ferreira, Salette Reis and Paulo Costa

Pharmaceuticals 2020, 13(9), 248; https://doi.org/10.3390/ph13090248 - 15 Sep 2020

Cited by 106 | Viewed by 12434

Abstract

The high incidence of fungal infections has become a worrisome public health issue, having been aggravated by an increase in host predisposition factors. Despite all the drugs available on the market to treat these diseases, their efficiency is questionable, and their side effects [...] Read more.

The high incidence of fungal infections has become a worrisome public health issue, having been aggravated by an increase in host predisposition factors. Despite all the drugs available on the market to treat these diseases, their efficiency is questionable, and their side effects cannot be neglected. Bearing that in mind, it is of upmost importance to synthetize new and innovative carriers for these medicines not only to fight emerging fungal infections but also to avert the increase in drug-resistant strains. Although it has revealed to be a difficult job, new nano-based drug delivery systems and even new cellular targets and compounds with antifungal potential are now being investigated. This article will provide a summary of the state-of-the-art strategies that have been studied in order to improve antifungal therapy and reduce adverse effects of conventional drugs. The bidirectional relationship between Mycology and Nanotechnology will be also explained. Furthermore, the article will focus on new compounds from the marine environment which have a proven antifungal potential and may act as platforms to discover drug-like characteristics, highlighting the challenges of the translation of these natural compounds into the clinical pipeline. Full article

(This article belongs to the Special Issue Advances in Antifungal Development: Discovery of New Drugs and Drug Repurposing)

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16 pages, 750 KiB

Open AccessReview

Clinical Evidence for Targeting NAD Therapeutically

by Dina Radenkovic, Reason and Eric Verdin

Pharmaceuticals 2020, 13(9), 247; https://doi.org/10.3390/ph13090247 - 15 Sep 2020

Cited by 37 | Viewed by 18898

Abstract

Nicotinamide adenine dinucleotide (NAD) pharmacology is a promising class of treatments for age-related conditions that are likely to have a favorable side effect profile for human use, given the widespread use of the NAD precursor vitamin B3 supplements. However, despite several decades of [...] Read more.

Nicotinamide adenine dinucleotide (NAD) pharmacology is a promising class of treatments for age-related conditions that are likely to have a favorable side effect profile for human use, given the widespread use of the NAD precursor vitamin B3 supplements. However, despite several decades of active investigation and numerous possible biochemical mechanisms of action suggested, only a small number of randomized and adequately powered clinical trials of NAD upregulation as a therapeutic strategy have taken place. We conducted a systematic review of the literature, following the PRISMA guidelines, in an attempt to determine whether or not the human clinical trials performed to date support the potential benefits of NAD supplementation in a range of skin, metabolic and age-related conditions. In addition, we sought medical indications that have yielded the most promising results in the limited studies to date. We conclude that promising, yet still speculative, results have been reported for the treatment of psoriasis and enhancement of skeletal muscle activity. However, further trials are required to determine the optimal method of raising NAD levels, identifying the target conditions, and comparisons to the present standard of care for these conditions. Lastly, pharmacological methods that increase NAD levels should also be directly compared to physiological means of raising NAD levels, such as exercise programs and dietary interventions that are tailored to older individuals, and which may be more effective. Full article

(This article belongs to the Special Issue Aging and Drug Discovery)

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14 pages, 931 KiB

Open AccessArticle

Evaluation of Tissue and Circulating miR-21 as Potential Biomarker of Response to Chemoradiotherapy in Rectal Cancer

by Susana Ourô, Cláudia Mourato, Marisa P. Ferreira, Diogo Albergaria, André Cardador, Rui E. Castro, Rui Maio and Cecília M. P. Rodrigues

Pharmaceuticals 2020, 13(9), 246; https://doi.org/10.3390/ph13090246 - 14 Sep 2020

Cited by 2 | Viewed by 3316

Abstract

Response to chemoradiotherapy (CRT) in patients with locally advanced rectal cancer (RC) is quite variable and it is urgent to find predictive biomarkers of response. We investigated miR-21 as tissue and plasma biomarker of response to CRT in a prospective cohort of RC [...] Read more.

Response to chemoradiotherapy (CRT) in patients with locally advanced rectal cancer (RC) is quite variable and it is urgent to find predictive biomarkers of response. We investigated miR-21 as tissue and plasma biomarker of response to CRT in a prospective cohort of RC patients; The expression of miR-21 was analyzed in pre- and post-CRT rectal tissue and plasma in 37 patients with RC. Two groups were defined: Pathological responders (TRG 0, 1 and 2) and non-responders (TRG 3). The association between miR-21, clinical and oncological outcomes was assessed; miR-21 was upregulated in tumor tissue and we found increased odds of overexpression in pre-CRT tumor tissue (OR: 1.63; 95% CI: 0.40–6.63, p = 0.498) and pre-CRT plasma (OR: 1.79; 95% CI: 0.45–7.19, p = 0.414) of non-responders. The overall recurrence risk increased with miR-21 overexpression in pre-CRT tumor tissue (HR: 2.175, p = 0.37); Significantly higher miR-21 expression is observed in tumor tissue comparing with non-neoplastic. Increased odds of non-response is reported in patients expressing higher miR-21, although without statistical significance. This is one of the first studies on circulating miR-21 as a potential biomarker of response to CRT in RC patients. Full article

(This article belongs to the Special Issue Cancer Translational Biomarkers and Targeted Therapies)

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31 pages, 8076 KiB

Open AccessReview

Antibody–Drug Conjugates: The Last Decade

by Nicolas Joubert, Alain Beck, Charles Dumontet and Caroline Denevault-Sabourin

Pharmaceuticals 2020, 13(9), 245; https://doi.org/10.3390/ph13090245 - 14 Sep 2020

Cited by 249 | Viewed by 31635

Abstract

An armed antibody (antibody–drug conjugate or ADC) is a vectorized chemotherapy, which results from the grafting of a cytotoxic agent onto a monoclonal antibody via a judiciously constructed spacer arm. ADCs have made considerable progress in 10 years. While in 2009 only gemtuzumab [...] Read more.

An armed antibody (antibody–drug conjugate or ADC) is a vectorized chemotherapy, which results from the grafting of a cytotoxic agent onto a monoclonal antibody via a judiciously constructed spacer arm. ADCs have made considerable progress in 10 years. While in 2009 only gemtuzumab ozogamicin (Mylotarg^®) was used clinically, in 2020, 9 Food and Drug Administration (FDA)-approved ADCs are available, and more than 80 others are in active clinical studies. This review will focus on FDA-approved and late-stage ADCs, their limitations including their toxicity and associated resistance mechanisms, as well as new emerging strategies to address these issues and attempt to widen their therapeutic window. Finally, we will discuss their combination with conventional chemotherapy or checkpoint inhibitors, and their design for applications beyond oncology, to make ADCs the magic bullet that Paul Ehrlich dreamed of. Full article

(This article belongs to the Special Issue Antibody-Drug Conjugates (ADC): 2021)

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14 pages, 626 KiB

Open AccessReview

Role of Chronic Lymphocytic Leukemia (CLL)-Derived Exosomes in Tumor Progression and Survival

by Nancy Nisticò, Domenico Maisano, Enrico Iaccino, Eleonora Vecchio, Giuseppe Fiume, Salvatore Rotundo, Ileana Quinto and Selena Mimmi

Pharmaceuticals 2020, 13(9), 244; https://doi.org/10.3390/ph13090244 - 14 Sep 2020

Cited by 22 | Viewed by 4426

Abstract

Chronic lymphocytic leukemia (CLL) is a B-lymphoproliferative disease, which consists of the abnormal proliferation of CD19/CD5/CD20/CD23 positive lymphocytes in blood and lymphoid organs, such as bone marrow, lymph nodes and spleen. The neoplastic transformation and expansion of tumor B cells are commonly recognized [...] Read more.

Chronic lymphocytic leukemia (CLL) is a B-lymphoproliferative disease, which consists of the abnormal proliferation of CD19/CD5/CD20/CD23 positive lymphocytes in blood and lymphoid organs, such as bone marrow, lymph nodes and spleen. The neoplastic transformation and expansion of tumor B cells are commonly recognized as antigen-driven processes, mediated by the interaction of antigens with the B cell receptor (BCR) expressed on the surface of B-lymphocytes. The survival and progression of CLL cells largely depend on the direct interaction of CLL cells with receptors of accessory cells of tumor microenvironment. Recently, much interest has been focused on the role of tumor release of small extracellular vesicles (EVs), named exosomes, which incorporate a wide range of biologically active molecules, particularly microRNAs and proteins, which sustain the tumor growth. Here, we will review the role of CLL-derived exosomes as diagnostic and prognostic biomarkers of the disease. Full article

(This article belongs to the Special Issue Exosomes as a Tool for Disease Progression Monitoring in Humans and Animals)

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16 pages, 646 KiB

Open AccessReview

Exosomal miRNAs as Potential Diagnostic Biomarkers in Alzheimer’s Disease

by Ida Manna, Selene De Benedittis, Andrea Quattrone, Domenico Maisano, Enrico Iaccino and Aldo Quattrone

Pharmaceuticals 2020, 13(9), 243; https://doi.org/10.3390/ph13090243 - 12 Sep 2020

Cited by 47 | Viewed by 5827

Abstract

Alzheimer’s disease (AD), a neurodegenerative disease, is linked to a variety of internal and external factors present from the early stages of the disease. There are several risk factors related to the pathogenesis of AD, among these exosomes and microRNAs (miRNAs) are of [...] Read more.

Alzheimer’s disease (AD), a neurodegenerative disease, is linked to a variety of internal and external factors present from the early stages of the disease. There are several risk factors related to the pathogenesis of AD, among these exosomes and microRNAs (miRNAs) are of particular importance. Exosomes are nanocarriers released from many different cell types, including neuronal cells. Through the transfer of bioactive molecules, they play an important role both in the maintenance of physiological and in pathological conditions. Exosomes could be carriers of potential biomarkers useful for the assessment of disease progression and for therapeutic applications. miRNAs are small noncoding endogenous RNA sequences active in the regulation of protein expression, and alteration of miRNA expression can result in a dysregulation of key genes and pathways that contribute to disease development. Indeed, the involvement of exosomal miRNAs has been highlighted in various neurodegenerative diseases, and this opens the possibility that dysregulated exosomal miRNA profiles may influence AD disease. The advances in exosome-related biomarker detection in AD are summarized. Finally, in this review, we highlight the use of exosomal miRNAs as essential biomarkers in preclinical and clinical studies in Alzheimer’s disease, also taking a look at their potential clinical value. Full article

(This article belongs to the Special Issue Exosomes as a Tool for Disease Progression Monitoring in Humans and Animals)

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36 pages, 7924 KiB

Open AccessReview

Marine Natural Products, Multitarget Therapy and Repurposed Agents in Alzheimer’s Disease

by Márcia Martins, Renata Silva, Madalena M. M. Pinto and Emília Sousa

Pharmaceuticals 2020, 13(9), 242; https://doi.org/10.3390/ph13090242 - 11 Sep 2020

Cited by 39 | Viewed by 7253

Abstract

Alzheimer’s disease (AD) is a multifactorial disease characterized by the presence of amyloid plaques, neurofibrillary tangles, and nerve cell death that affects, mainly, older people. After decades of investigation, the search for an efficacious treatment for AD remains and several strategies can be [...] Read more.

Alzheimer’s disease (AD) is a multifactorial disease characterized by the presence of amyloid plaques, neurofibrillary tangles, and nerve cell death that affects, mainly, older people. After decades of investigation, the search for an efficacious treatment for AD remains and several strategies can be and are being employed in this journey. In this review, four of the most promising strategies, alongside with its most promising agents under investigation or development are highlighted. Marine natural products (MNP) are a source of unique chemical structures with useful biological activities for AD treatment. One of the most promising compounds, a marine-derived acidic oligosaccharide (GV-971) just passed phase III clinical trials with a unique mechanism of action. Combination therapy and multitargeted-directed ligand therapy (MTDL) are also two important strategies, with several examples in clinical trials, based on the belief that the best approach for AD is a therapy capable of modulating multiple target pathways. Drug repurposing, a strategy that requires a smaller investment and is less time consuming, is emerging as a strong contender with a variety of pharmacological agents resurfacing in an attempt to identify a therapeutic candidate capable of modifying the course of this disease. Full article

(This article belongs to the Special Issue Therapeutic Agents for Neurological Disorders)

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16 pages, 2512 KiB

Open AccessArticle

Silencing of Exosomal miR-181a Reverses Pediatric Acute Lymphocytic Leukemia Cell Proliferation

by Shabirul Haque and Sarah R. Vaiselbuh

Pharmaceuticals 2020, 13(9), 241; https://doi.org/10.3390/ph13090241 - 11 Sep 2020

Cited by 29 | Viewed by 3412

Abstract

Exosomes are cell-generated nano-vesicles found in most biological fluids. Major components of their cargo are lipids, proteins, RNA, DNA, and non-coding RNAs. The miRNAs carried within exosomes reveal real-time information regarding disease status in leukemia and other cancers, and therefore exosomes have been [...] Read more.

Exosomes are cell-generated nano-vesicles found in most biological fluids. Major components of their cargo are lipids, proteins, RNA, DNA, and non-coding RNAs. The miRNAs carried within exosomes reveal real-time information regarding disease status in leukemia and other cancers, and therefore exosomes have been studied as novel biomarkers for cancer. We investigated the impact of exosomes on cell proliferation in pediatric acute lymphocytic leukemia (PALL) and its reversal by silencing of exo-miR-181a. We isolated exosomes from the serum of PALL patients (Exo-PALL) and conditioned medium of leukemic cell lines (Exo-CM). We found that Exo-PALL promotes cell proliferation in leukemic B cell lines by gene regulation. This exosome-induced cell proliferation is a precise event with the up-regulation of proliferative (PCNA, Ki-67) and pro-survival genes (MCL-1, and BCL2) and suppression of pro-apoptotic genes (BAD, BAX). Exo-PALL and Exo-CM both show over expression of miR-181a compared to healthy donor control exosomes (Exo-HD). Specific silencing of exosomal miR-181a using a miR-181a inhibitor confirms that miR-181a inhibitor treatment reverses Exo-PALL/Exo-CM-induced leukemic cell proliferation in vitro. Altogether, this study suggests that exosomal miR-181a inhibition can be a novel target for growth suppression in pediatric lymphatic leukemia. Full article

(This article belongs to the Special Issue MiRNA-Based Therapeutics in Cancer)

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19 pages, 3180 KiB

Open AccessArticle

A New Insight into Meloxicam: Assessment of Antioxidant and Anti-Glycating Activity in In Vitro Studies

by Cezary Pawlukianiec, Małgorzata Ewa Gryciuk, Kacper Maksymilian Mil, Małgorzata Żendzian-Piotrowska, Anna Zalewska and Mateusz Maciejczyk

Pharmaceuticals 2020, 13(9), 240; https://doi.org/10.3390/ph13090240 - 10 Sep 2020

Cited by 29 | Viewed by 5684

Abstract

Meloxicam is a non-steroidal anti-inflammatory drug, which has a preferential inhibitory effect to cyclooxyganase-2 (COX-2). Although the drug inhibits prostaglandin synthesis, the exact mechanism of meloxicam is still unknown. This is the first study to assess the effect of meloxicam on protein glyco-oxidation [...] Read more.

Meloxicam is a non-steroidal anti-inflammatory drug, which has a preferential inhibitory effect to cyclooxyganase-2 (COX-2). Although the drug inhibits prostaglandin synthesis, the exact mechanism of meloxicam is still unknown. This is the first study to assess the effect of meloxicam on protein glyco-oxidation as well as antioxidant activity. For this purpose, we used an in vitro model of oxidized bovine serum albumin (BSA). Glucose, fructose, ribose, glyoxal and methylglyoxal were used as glycating agents, while chloramine T was used as an oxidant. We evaluated the antioxidant properties of albumin (2,2-di-phenyl-1-picrylhydrazyl radical scavenging capacity, total antioxidant capacity and ferric reducing antioxidant power), the intensity of protein glycation (Amadori products, advanced glycation end products) and glyco-oxidation (dityrosine, kynurenine, N-formylkynurenine, tryptophan and amyloid-β) as well as the content of protein oxidation products (advanced oxidation protein products, carbonyl groups and thiol groups). We have demonstrated that meloxicam enhances the antioxidant properties of albumin and prevents the protein oxidation and glycation under the influence of various factors such as sugars, aldehydes and oxidants. Importantly, the antioxidant and anti-glycating activity is similar to that of routinely used antioxidants such as captopril, Trolox, reduced glutathione and lipoic acid as well as protein glycation inhibitors (aminoguanidine). Pleiotropic action of meloxicam may increase the effectiveness of anti-inflammatory treatment in diseases with oxidative stress etiology. Full article

(This article belongs to the Section Medicinal Chemistry)

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Chemical structure of meloxicam. Full article ">Figure 2
The effects of meloxicam, captopril, trolox, reduced glutathione, lipoic acid, aminoguanidine or metformin addition to BSA + glucose solution on protein glycation (A–C), glycooxidation (D–G) and oxidative damage (H–J) as well as total antioxidant potential (K–M). AGE: advanced glycation end products; AOPP: advanced oxidation protein products; BSA: bovine serum albumin; DPPH: 2,2-di-phenyl-1-picrylhydrazyl radical scavenging capacity; FRAP: ferric reducing antioxidant power; Glc: glucose; PC: protein carbonyls; TAC: total antioxidant capacity; ns: not significant vs. control; * p < 0.05 vs. control; ** p < 0.01 vs. control; *** p < 0.001 vs. control; **** p < 0.0001 vs. control. Full article ">Figure 3
The effects of meloxicam, captopril, trolox, reduced glutathione, lipoic acid, aminoguanidine or metformin addition to BSA + fructose solution on protein glycation (A–C), glycooxidation (D–G) and oxidative damage (H–J) as well as total antioxidant potential (K–M). AGE: advanced glycation end products; AOPP: advanced oxidation protein products; BSA: bovine serum albumin; DPPH: 2,2-di-phenyl-1-picrylhydrazyl radical scavenging capacity; FRAP: ferric reducing antioxidant power; Fru: fructose; PC: protein carbonyls; TAC: total antioxidant capacity; ns: not significant vs. control; * p < 0.05 vs. control; ** p < 0.01 vs. control; *** p < 0.001 vs. control; **** p < 0.0001 vs. control. Full article ">Figure 4
The effects of meloxicam, captopril, trolox, reduced glutathione, lipoic acid, aminoguanidine or metformin addition to BSA + ribose solution on protein glycation (A–C), glycooxidation (D–G) and oxidative damage (H–J) as well as total antioxidant potential (K–M). AGE: advanced glycation end products; AOPP: advanced oxidation protein products; BSA: bovine serum albumin; DPPH: 2,2-di-phenyl-1-picrylhydrazyl radical scavenging capacity; FRAP: ferric reducing antioxidant power; PC: protein carbonyls; Rib: ribose; TAC: total antioxidant capacity; ns: not significant vs. control; * p < 0.05 vs. control; ** p < 0.01 vs. control; *** p < 0.001 vs. control; **** p < 0.0001 vs. control. Full article ">Figure 5
The effects of meloxicam, captopril, trolox, reduced glutathione, lipoic acid, aminoguanidine or metformin addition to BSA + glyoxal solution on protein glycation (A–C), glycooxidation (D–G) and oxidative damage (H–J) as well as total antioxidant potential (K–M). AGE: advanced glycation end products; AOPP: advanced oxidation protein products; BSA: bovine serum albumin; DPPH: 2,2-di-phenyl-1-picrylhydrazyl radical scavenging capacity; FRAP: ferric reducing antioxidant power; GO: glyoxal; PC: protein carbonyls; TAC: total antioxidant capacity; ns: not significant vs. control; * p < 0.05 vs. control; ** p < 0.01 vs. control; *** p < 0.001 vs. control; **** p < 0.0001 vs. control. Full article ">Figure 6
The effects of meloxicam, captopril, trolox, reduced glutathione, lipoic acid, aminoguanidine or metformin addition to BSA + methylglyoxal solution on protein glycation (A–C), glycooxidation (D–G) and oxidative damage (H–J) as well as total antioxidant potential (K–M). AGE: advanced glycation end products; AOPP: advanced oxidation protein products; BSA: bovine serum albumin; DPPH: 2,2-di-phenyl-1-picrylhydrazyl radical scavenging capacity; FRAP: ferric reducing antioxidant power; MGO: methylglyoxal; PC: protein carbonyls; TAC: total antioxidant capacity; ns: not significant vs. control; * p < 0.05 vs. control; ** p < 0.01 vs. control; *** p < 0.001 vs. control; **** p < 0.0001 vs. control. Full article ">Figure 7
The effects of meloxicam, captopril, trolox, reduced glutathione, lipoic acid, aminoguanidine or metformin addition to BSA + chloramine T solution on protein glycation (A–C), glycooxidation (D–G) and oxidative damage (H–J) as well as total antioxidant potential (K–M). AGE: advanced glycation end products; AOPP: advanced oxidation protein products; BSA: bovine serum albumin; DPPH: 2,2-di-phenyl-1-picrylhydrazyl radical scavenging capacity; FRAP: ferric reducing antioxidant power; PC: protein carbonyls; TAC: total antioxidant capacity; ns: not significant vs. control; * p < 0.05 vs. control; ** p < 0.01 vs. control; *** p < 0.001 vs. control; **** p < 0.0001 vs. control. Full article ">

17 pages, 1347 KiB

Open AccessArticle

Incubation with a Complex Orange Essential Oil Leads to Evolved Mutants with Increased Resistance and Tolerance

by Daniel Berdejo, Elisa Pagán, Natalia Merino, Rafael Pagán and Diego García-Gonzalo

Pharmaceuticals 2020, 13(9), 239; https://doi.org/10.3390/ph13090239 - 9 Sep 2020

Cited by 8 | Viewed by 2981

Abstract

Emergence of strains with increased resistance/tolerance to natural antimicrobials was evidenced after cyclic exposure to carvacrol, citral, and (+)-limonene oxide. However, no previous studies have reported the development of resistance and tolerance to complex essential oils (EOs). This study seeks to evaluate the [...] Read more.

Emergence of strains with increased resistance/tolerance to natural antimicrobials was evidenced after cyclic exposure to carvacrol, citral, and (+)-limonene oxide. However, no previous studies have reported the development of resistance and tolerance to complex essential oils (EOs). This study seeks to evaluate the occurrence of Staphylococcus aureus strains resistant and tolerant to a complex orange essential oil (OEO) after prolonged cyclic treatments at low concentrations. Phenotypic characterization of evolved strains revealed an increase of minimum inhibitory and bactericidal concentration for OEO, a better growth fitness in presence of OEO, and an enhanced survival to lethal treatments, compared to wild-type strain. However, no significant differences (p > 0.05) in cross-resistance to antibiotics were observed. Mutations in hepT and accA in evolved strains highlight the important role of oxidative stress in the cell response to OEO, as well as the relevance of the cell membrane in the cell response to these natural antimicrobials. This study demonstrates the emergence of S. aureus strains that are resistant and tolerant to EO (Citrus sinensis). This phenomenon should be taken into account to assure the efficacy of natural antimicrobials in the design of food preservation strategies, in cleaning and disinfection protocols, and in clinical applications against resistant bacteria. Full article

(This article belongs to the Special Issue Bioactive Compounds from Plants and Foods with Pharmaceutical Interest)

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Full article ">Figure 1
Growth curves of Staphylococcus aureus USA300 (A; SaWT) and evolved strain (B; SaROEO) in the absence (▬) and presence of 250 (▬), 500 (▬), 750 (▬), 1000 (▬), 1250 (▬), 1500 (▬), 2000 (▬), 5000 (▬) of orange essential oil (OEO), modelled using the modified Gompertz equation (Equation (1)). Full article ">Figure 2
Survival curves of Staphylococcus aureus USA300 (●; SaWT) and evolved strain (●; SaROEO), after 2000 µL/L orange essential oil (OEO) treatment at pH 7.0 (A) and pH 4.0 (B) at 37 °C. Data are means ± standard deviations (error bars) obtained from at least 3 independents experiments. Dashed line represents the detection limit (−5.0 log10). Full article ">Figure 3
Mutagenesis frequency in S. aureus USA300 grown in broth (control, ■) and with orange essential oil (OEO; 750 µL/L; ■), carvacrol (50 µL/L, ■) and rifampicin (0.01 mg/L, ■). Mutagenesis frequency was expressed as rifampicin-resistant cells in the total microbial population. Data are means ± standard deviations (error bars) obtained from five independent experiments. ns: no statistically significant differences (p > 0.05); ***: statistically significant differences (p ≤ 0.001), in comparison with control. Full article ">Figure 4
Genomic map of evolved strain (SaROEO) in comparison with Staphylococcus aureus USA300 (SaWT). Full article ">

8 pages, 980 KiB

Open AccessOpinion

Can Nuclear Imaging of Activated Macrophages with Folic Acid-Based Radiotracers Serve as a Prognostic Means to Identify COVID-19 Patients at Risk?

by Cristina Müller, Roger Schibli and Britta Maurer

Pharmaceuticals 2020, 13(9), 238; https://doi.org/10.3390/ph13090238 - 9 Sep 2020

Cited by 9 | Viewed by 3914

Abstract

Herein, we discuss the potential role of folic acid-based radiopharmaceuticals for macrophage imaging to support clinical decision-making in patients with COVID-19. Activated macrophages play an important role during coronavirus infections. Exuberant host responses, i.e., a cytokine storm with increase of macrophage-related cytokines, such [...] Read more.

Herein, we discuss the potential role of folic acid-based radiopharmaceuticals for macrophage imaging to support clinical decision-making in patients with COVID-19. Activated macrophages play an important role during coronavirus infections. Exuberant host responses, i.e., a cytokine storm with increase of macrophage-related cytokines, such as TNFα, IL-1β, and IL-6 can lead to life-threatening complications, such as acute respiratory distress syndrome (ARDS), which develops in approximately 20% of the patients. Diverse immune modulating therapies are currently being tested in clinical trials. In a preclinical proof-of-concept study in experimental interstitial lung disease, we showed the potential of ¹⁸F-AzaFol, an ¹⁸F-labeled folic acid-based radiotracer, as a specific novel imaging tool for the visualization and monitoring of macrophage-driven lung diseases. ¹⁸F-AzaFol binds to the folate receptor-beta (FRβ) that is expressed on activated macrophages involved in inflammatory conditions. In a recent multicenter cancer trial, ¹⁸F-AzaFol was successfully and safely applied (NCT03242993). It is supposed that the visualization of activated macrophage-related disease processes by folate radiotracer-based nuclear imaging can support clinical decision-making by identifying COVID-19 patients at risk of a severe disease progression with a potentially lethal outcome. Full article

(This article belongs to the Special Issue COVID-19 in Pharmaceuticals)

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14 pages, 2337 KiB

Open AccessReview

Tumor Immunotherapy Using A_2A Adenosine Receptor Antagonists

by Jinfeng Zhang, Wenzhong Yan, Wenwen Duan, Kurt Wüthrich and Jianjun Cheng

Pharmaceuticals 2020, 13(9), 237; https://doi.org/10.3390/ph13090237 - 8 Sep 2020

Cited by 24 | Viewed by 6444

Abstract

The A_2A adenosine receptor (A_2AAR) plays critical roles in human physiology and pathophysiology, which makes it an important drug target. Previous drug-discovery efforts targeting the A_2AAR have been focused on the use of A_2AAR antagonists for [...] Read more.

The A_2A adenosine receptor (A_2AAR) plays critical roles in human physiology and pathophysiology, which makes it an important drug target. Previous drug-discovery efforts targeting the A_2AAR have been focused on the use of A_2AAR antagonists for the treatment of Parkinson’s disease. More recently, the A_2AAR has attracted additional attention for its roles in immuno-oncology, and a number of A_2AAR antagonists are currently used as lead compounds for antitumor drugs in both preclinical models and clinical trials. This review surveys recent advances in the development of A_2AAR antagonists for cancer immunotherapy. The therapeutic potential of representative A_2AAR antagonists is discussed based on both animal efficacy studies and clinical data. Full article

(This article belongs to the Special Issue GPCRs: Ligands and beyond 2022)

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Adenosine-A2AAR signaling in the tumor microenvironment (the green circles represent adenosine molecules). ATP = adenosine triphosphate; AMP = adenosine monophosphate. Full article ">Figure 2
Chemical structures of A2AAR antagonists discussed in this chapter. Full article ">Figure 3
Binding modes of A2AAR with different antagonists. (A) ZM-241385; the key amino acid residues: Asn2536.55, Glu1695.30, Phe1685.29, Trp2466.48, and Ile2747.39 are identified (PDB ID: 3EML). (B) SYN-115; the key amino acid residues: Asn2536.55, Thr2566.58, Phe1685.29, and Trp2466.48 are identified (PDB ID: 5OLO). (C) AZD-4635; the key amino acid residues: Asn2536.55, Glu1695.30, Phe1685.29, and Trp2466.48 are identified (PDB ID: 6GT3). (D) V-2006; the key amino acid residues: Asn2536.55, Glu1695.30, Tyr91.35, Phe1685.29, and Trp2466.48 are identified (PDB ID: 5OLH). The A2AAR back bone is colored gray, and the amino acid side chains that interact with the ligands are shown as sticks and colored by element (carbon, yellow; nitrogen, blue; oxygen, red; sulfur, yellow; the side chain of Asn2536.55 is shown in a space filling presentation). The antagonists are shown as sticks and colored by element (carbon, green; nitrogen, blue; oxygen, red; sulfur, yellow). Polar contacts are presented as dashed lines, and water molecules are shown as red spheres. Full article ">

32 pages, 1804 KiB

Open AccessReview

The Role of Adaptogens in Prophylaxis and Treatment of Viral Respiratory Infections

by Alexander Panossian and Thomas Brendler

Pharmaceuticals 2020, 13(9), 236; https://doi.org/10.3390/ph13090236 - 8 Sep 2020

Cited by 42 | Viewed by 12409

Abstract

The aim of our review is to demonstrate the potential of herbal preparations, specifically adaptogens for prevention and treatment of respiratory infections, as well as convalescence, specifically through supporting a challenged immune system, increasing resistance to viral infection, inhibiting severe inflammatory progression, and [...] Read more.

The aim of our review is to demonstrate the potential of herbal preparations, specifically adaptogens for prevention and treatment of respiratory infections, as well as convalescence, specifically through supporting a challenged immune system, increasing resistance to viral infection, inhibiting severe inflammatory progression, and driving effective recovery. The evidence from pre-clinical and clinical studies with Andrographis paniculata, Eleutherococcus senticosus, Glycyrrhiza spp., Panax spp., Rhodiola rosea, Schisandra chinensis, Withania somnifera, their combination products and melatonin suggests that adaptogens can be useful in prophylaxis and treatment of viral infections at all stages of progression of inflammation as well as in aiding recovery of the organism by (i) modulating innate and adaptive immunity, (ii) anti-inflammatory activity, (iii) detoxification and repair of oxidative stress-induced damage in compromised cells, (iv) direct antiviral effects of inhibiting viral docking or replication, and (v) improving quality of life during convalescence. Full article

(This article belongs to the Special Issue Medicinal Plants and Natural Compounds for Modulation of Neuroendocrine-Immune System and Potential Use in Ageing-Related Disorders)

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18 pages, 5928 KiB

Open AccessArticle

Combination Therapy with Doxorubicin-Loaded Reduced Albumin Nanoparticles and Focused Ultrasound in Mouse Breast Cancer Xenografts

by Daehyun Kim, Seung Soo Lee, Woo Young Yoo, Hyungwon Moon, Aesin Cho, So Yeon Park, Yoon-Seok Kim, Hyun Ryoung Kim and Hak Jong Lee

Pharmaceuticals 2020, 13(9), 235; https://doi.org/10.3390/ph13090235 - 7 Sep 2020

Cited by 15 | Viewed by 4261

Abstract

Because chemotherapeutic drugs are often associated with serious side effects, the central topic in modern drug delivery is maximizing the localization of drugs at the target while minimizing non-specific drug interactions at unwanted regions. To address this issue, biocompatible nanoparticles have been developed [...] Read more.

Because chemotherapeutic drugs are often associated with serious side effects, the central topic in modern drug delivery is maximizing the localization of drugs at the target while minimizing non-specific drug interactions at unwanted regions. To address this issue, biocompatible nanoparticles have been developed to enhance the drug half-life while minimizing the associated toxicity. Nevertheless, relying solely on the enhanced half-life and enhanced permeability and retention (EPR) effects has been ineffective, and designing stimulus-sensitive nanoparticles to introduce the precise control of drug release has been desired. In this paper, we introduce a pH-sensitive, reduced albumin nanoparticle in combination with focused ultrasound treatment. Not only did these nanoparticles have superior therapeutic efficacy and toxicity profiles when compared to the free drugs in xenograft mouse models, but we were also able to show that the albumin nanoparticles reported in this paper were more suitable than other types of non-reduced albumin nanoparticles as vehicles for drug delivery. As such, we believe that the albumin nanoparticles presented in this paper with desirable characteristics including the induction of strong anti-tumor response, precise control, and superior safety profiles hold strong potential for preclinical and clinical anticancer therapy. Full article

(This article belongs to the Special Issue Nano Drug Carriers 2021)

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16 pages, 1233 KiB

Open AccessReview

Metformin: A Potential Therapeutic Tool for Rheumatologists

by Teresa Salvatore, Pia Clara Pafundi, Raffaele Galiero, Klodian Gjeloshi, Francesco Masini, Carlo Acierno, Anna Di Martino, Gaetana Albanese, Maria Alfano, Luca Rinaldi and Ferdinando Carlo Sasso

Pharmaceuticals 2020, 13(9), 234; https://doi.org/10.3390/ph13090234 - 4 Sep 2020

Cited by 40 | Viewed by 8452

Abstract

Metformin is an oral antihyperglycemic drug widely used to treat type 2 diabetes, acting via indirect activation of 5′ Adenosine Monophosphate-activated Protein Kinase (AMPK). Actually, evidence has accumulated of an intriguing anti-inflammatory activity, mainly mediated by AMPK through a variety of mechanisms such [...] Read more.

Metformin is an oral antihyperglycemic drug widely used to treat type 2 diabetes, acting via indirect activation of 5′ Adenosine Monophosphate-activated Protein Kinase (AMPK). Actually, evidence has accumulated of an intriguing anti-inflammatory activity, mainly mediated by AMPK through a variety of mechanisms such as the inhibition of cytokine-stimulated Nuclear Factor-κB (NF-κB) and the downregulation of the Janus Kinase/Signal Transducer and Activator of Transcription (JAK/STAT) signaling pathways. Moreover, AMPK plays an important role in the modulation of T lymphocytes and other pivotal cells of the innate immune system. The current understanding of these AMPK effects provides a strong rationale for metformin repurposing in the management of autoimmune and inflammatory conditions. Several studies demonstrated metformin’s beneficial effects on both animal and human rheumatologic diseases, especially on rheumatoid arthritis. Unfortunately, even though data are large and remarkable, they almost exclusively come from experimental investigations with only a few from clinical trials. The lack of support from prospective placebo-controlled trials does not allow metformin to enter the therapeutic repertoire of rheumatologists. However, a large proportion of rheumatologic patients can currently benefit from metformin, such as those with concomitant obesity and type 2 diabetes, two conditions strongly associated with rheumatoid arthritis, osteoarthritis, and gout, as well as those with diabetes secondary to steroid therapy. Full article

(This article belongs to the Special Issue Metformin: Mechanism and Application 2022)

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