Search Results (1,153)

Background/Objectives: Glioblastoma multiforme (GBM) is the most common high-grade primary brain cancer in adults. Despite efforts to advance treatment, GBM remains treatment resistant and inevitably progresses after first-line therapy. Induced neural stem cell (iNSC) therapy is a promising, personalized cell therapy approach that has been explored to circumvent challenges associated with the current GBM treatment. Methods: Herein, we developed a chitosan-based (CS) injectable, biodegradable, in situ forming thermo-responsive hydrogel as a cell delivery vehicle for the treatment of GBM. Tumoricidal neural stem cells were encapsulated in the injectable CS hydrogel as stem cell therapy for treatment of post-surgical GBM. In this report, we investigated the safety of the injectable CS hydrogel in an immune-competent mouse model. Furthermore, we evaluated the persistence and efficacy of iNSC-laden CS hydrogels in a post-surgical GBM mouse model. Results: The injectable CS hydrogel was well tolerated in mice with no signs of chronic local inflammation. Induced neural stem cells (iNSCs) persisted in the CS hydrogels for over 196 days in comparison to 21 days for iNSCs (cell injection) only. GBM recurrence was significantly slower in mice treated with iNSC-laden CS hydrogels with a 50% increase in overall median survival in comparison to iNSCs (cell injection) only. Conclusions: Collectively, we demonstrated the ability to encapsulate, retain, and deliver iNSCs in an injectable CS hydrogel that is well tolerated with better survival rates than iNSCs alone. Full article

Background and Objectives: Current craniofacial reconstruction surgical methods have limitations because they involve facial deformation. The craniofacial region includes many areas where the mucosa, exposed to air, is closely adjacent to bone, with the maxilla being a prominent example of this structure. Therefore, this study explored whether human neural-crest-derived stem cells (hNTSCs) aid bone and airway mucosal regeneration during craniofacial reconstruction using a rabbit model. Materials and Methods: hNTSCs were induced to differentiate into either mucosal epithelial or osteogenic cells in vitro. hNTSCs were seeded into polycaprolactone scaffold (three-dimensionally printed) that were implanted into rabbits with maxillary defects. Four weeks later, tissue regeneration was analyzed via histological evaluation and immunofluorescence staining. Results: In vitro, hNTSCs differentiated into both mucosal epithelial and osteogenic cells. hNTSC differentiation into respiratory epithelial cells was confirmed by Alcian Blue staining, cilia in SEM, and increased expression levels of FOXJ1 and E-cadherin through quantitative RT-PCR. hNTSC differentiation into bone was confirmed by Alizarin Red staining, increased mRNA expression levels of BMP2 (6.1-fold) and RUNX2 (2.3-fold) in the hNTSC group compared to the control. Four weeks post-transplantation, the rabbit maxilla was harvested, and H&E, SEM, and immunohistofluorescence staining were performed. H&E staining and SEM showed that new tissue and cilia around the maxillary defect were more prominent in the hNTSC group. Also, the hNTSCs group showed positive immunohistofluorescence staining for acetylated α-tubulin and cytokerin-5 compared to the control group. Conclusions: hNTSCs combined with PCL scaffold enhanced the regeneration of mucosal tissue and bone in vitro and promoted mucosal tissue regeneration in the in vivo rabbit model. Full article

The failure of endogenous repair mechanisms is a key characteristic of neurological diseases, leading to the inability to restore damaged nerves and resulting in functional impairments. Since the endogenously regenerative capacity of damaged nerves is limited, the enhancement of regenerative potential of quiescent neural stem cells (NSCs) presents as a therapeutic option for neural diseases. Our previous studies have shown exciting progress in treating sciatic nerve injury in mice and rats using NSCs in conjunction with neurotrophic factors such as fibroblast growth factor 1 (FGF1). Additionally, a recently discovered neurotrophic factor, IL12p80, has shown significant therapeutic effects in sciatic nerve injury repair via myelinating oligodendrocytes. IL12p80 induces oligodendrocyte differentiation from NSCs through phosphorylation of Stat3. Therefore, it might be possible to alleviate the myelination defects of oligodendrocytes in neurodegenerative diseases such as amyotrophic lateral sclerosis (ALS), multiple sclerosis (MS), and even schizophrenia through the administration of IL12p80. These applications could shed light on IL12p80 and FGF1, not only in damaged nerve repair, but also in rectifying the oligodendrocytes’ defects in neurodegenerative diseases, such as ALS and MS. Finally, the synergistic effects of neurogenesis-induced FGF1 and myelination-induced IL12 might be able to supplant the need of NSCs for nerve repair and neuroregeneration. Full article

Cognitive decline is a natural process that occurs during aging. Several natural solutions called nootropics exist that can help mitigate this process. However, in some cases, there is a lack of scientific evidence on their potential mechanisms and efficacy. To this end, a total of nine different herb extracts with potential nootropic activity were evaluated. These herb extracts were tested in human neural stem cell cultures exposed to oxidative stress, where reactive oxygen/nitrogen species, cell survival and trophic factor expression were analyzed. Of these extracts, Salvia officinalis (sage) was observed to possess the most significant effect. Its combination with rutin demonstrated additional benefits than with only sage. A randomized, double-blind placebo-controlled clinical study was then performed, testing the effects of the combination at two different doses for 12 weeks in healthy volunteers aged 50+ with mild cognitive impairment. As a result, the blend significantly improved several characteristics related to memory, particularly memory recall, with a more noticeable effect in the higher dose. Therefore, this study reveals the potential nootropic effect of a blend comprising Salvia officinalis and rutin. This blend could be a candidate dietary ingredient with potential nootropic properties. Full article

Spinal cord injury (SCI) disrupts the blood–spinal cord barrier (BSCB) exacerbating damage by allowing harmful substances and immune cells to infiltrate spinal neural tissues from the vasculature. This leads to inflammation, oxidative stress, and impaired axonal regeneration. The BSCB, essential for maintaining spinal cord homeostasis, is structurally similar to the blood–brain barrier. Its restoration is a key therapeutic target for improving outcomes in SCI. Mesenchymal stromal/stem cells (MSCs) and their secreted extracellular vesicles (MSC-EVs) have gained attention for their regenerative, immunomodulatory, and anti-inflammatory properties in promoting BSCB repair. MSCs enhance BSCB integrity by improving endothelial–pericyte association, restoring tight junction proteins, and reducing inflammation. MSC-EVs, which deliver bioactive molecules, replicate many of MSCs’ therapeutic effects, and offer a promising cell-free alternative. Preclinical studies have shown that both MSCs and MSC-EVs can reduce BSCB permeability, promote vascular stability, and support functional recovery. While MSC therapy is advancing in clinical trials, MSC-EV therapies require further optimization in terms of production, dosing, and delivery protocols. Despite these challenges, both therapeutic approaches represent significant potential for treating SCI by targeting BSCB repair and improving patient outcomes. Full article

The gold standard assay for radiation response is the clonogenic assay, a normalized colony formation assay (CFA) that can capture a broad range of radiation-induced cell death mechanisms. Traditionally, this assay relies on two-dimensional (2D) cell culture conditions with colonies counted by fixing and staining protocols. While some groups have converted these to three-dimensional (3D) conditions, these models still utilize 2D-like media compositions containing serum that are incompatible with stem-like cell models such as brain tumor initiating cells (BTICs) that form self-aggregating spheroids in neural stem cell media. BTICs are the preferred patient-derived model system for studying glioblastoma (GBM) as they tend to better retain molecular and phenotypic characteristics of the original tumor tissue. As such, it is important that preclinical radiation studies should be adapted to BTIC conditions. In this study, we describe a series of experimental approaches for performing CFA experiments with BTIC cultures. Our results indicate that serum-free clonogenic assays are feasible for combination drug and radiation testing and may better facilitate translatability of preclinical findings. Full article

The translocator protein 18 kDa (TSPO) is a multifunctional outer mitochondrial membrane protein associated with various aspects of mitochondrial physiology and multiple roles in health and disease. Here, we aimed to analyse the role of TSPO in the regulation of mitochondrial and cellular functions in a human neuronal cell model. We used the CRISPR/Cas9 technology and generated TSPO knockout (KO) and control (CTRL) variants of human-induced pluripotent stem cells (hiPSCs). In a multimodal phenotyping approach, we investigated cellular and mitochondrial functions in neural progenitor cells (NPCs), astrocytes, and neurons differentiated from hiPSC CTRL and TSPO KO cell lines. Our analysis revealed reduced mitochondrial respiration and glycolysis, altered Ca²⁺ levels in the cytosol and mitochondrial matrix, a depolarised MMP, and increased levels of reactive oxygen species, as well as a reduced cell size. Notably, TSPO deficiency was accompanied by reduced expression of the voltage-dependent anion channel (VDAC). We also observed a reduced TSPO and VDAC expression in cells derived from patients suffering from major depressive disorder (MDD). Considering the modulatory function of TSPO and the similar functional phenotype of cells derived from patients with depression, we discuss a role of TSPO in the etiology or pathology of MDD. In summary, our findings indicate a general impairment of mitochondrial function in TSPO knockout (KO) cells. This deepens our insight into the intricate role of TSPO in a range of physiological and pathological processes. Full article

As the global population ages, the rising prevalence of neurodegenerative diseases, characterized by abnormal protein aggregates, presents significant challenges for early diagnosis and disease monitoring. Identifying accessible tissue biomarkers is crucial for advancing our ability to detect and track the progression of these diseases. Among the most promising biomarkers is the skin, which shares a common embryological origin with the brain and central nervous system (CNS). This biological connection positions the skin as a potential reflection of CNS pathology. Over the past decades, gene expression studies have demonstrated that key genes involved in neurodegenerative diseases are also expressed in skin tissues. Genes such as APP, PSEN1, PPA2, PINK1, LRRK2, PLCB4, MAPT, SPAST, and SPG7 are prominent in this regard. Beyond gene expression, proteins related to neurodegenerative diseases—such as α-synuclein, TAU, PARKIN, and prion protein (PrP)—have been isolated from the skin of affected individuals, underscoring the skin’s capacity to mirror neural degeneration. This non-invasive window into neurodegenerative processes is further enhanced by advances in stem cell technology, which have allowed for the generation of human-induced pluripotent stem cells (iPSCs) from patient-derived fibroblasts. These iPSCs offer a valuable model for studying disease mechanisms and developing therapeutic approaches. This review conducts a comprehensive analysis of the literature from databases such as PubMed, Google Scholar, and ResearchGate, emphasizing the unique potential of the skin as a non-invasive biomarker for neurodegenerative diseases. It explores how the skin serves as a bridge between gene expression and disease pathology in both the skin and the CNS. By leveraging this biological connection, the skin emerges as a promising model for enhancing our understanding of neurodegenerative disorders and developing innovative strategies for early detection and treatment. However, significant limitations remain, requiring further validation to establish the specificity and sensitivity of these biomarkers. Full article

There has been a recent drive to replace in vivo studies with in vitro studies in the field of toxicity testing. Therefore, instead of conventional animal or planar cell culture models, there is an urgent need for in vitro systems whose conditions can be strictly controlled, including cell–cell interactions and sensitivity to low doses of chemicals. Neural organoids generated from human-induced pluripotent stem cells (iPSCs) are a promising in vitro platform for modeling human brain development. In this study, we developed a new tool based on various iPSCs to study and predict chemical-induced toxicity in humans. The model displayed several neurodevelopmental features and showed good reproducibility, comparable to that of previously published models. The results revealed that basic fibroblast growth factor plays a key role in the formation of the embryoid body, as well as complex neural networks and higher-order structures such as layered stacking. Using organoid models, pesticide toxicities were assessed. Cells treated with low concentrations of rotenone underwent apoptosis to a greater extent than those treated with high concentrations of rotenone. Morphological changes associated with the development of neural progenitor cells were observed after exposure to low doses of chlorpyrifos. These findings suggest that the neuronal organoids developed in this study mimic the developmental processes occurring in the brain and nerves and are a useful tool for evaluating drug efficacy, safety, and toxicity. Full article

The main purpose of regenerative medicine for degenerative eye diseases is to create cells to replace lost or damaged ones. Due to their anatomical, genetic, and epigenetic features, characteristics of origin, evolutionary inheritance, capacity for dedifferentiation, proliferation, and plasticity, mammalian and human RPE cells are of great interest as endogenous sources of new photoreceptors and other neurons for the degrading retina. Promising methods for the reprogramming of RPE cells into retinal cells include genetic methods and chemical methods under the influence of certain low-molecular-weight compounds, so-called small molecules. Depending on the goal, which can be the preservation or the replacement of lost RPE cells and cellular structures, various small molecules are used to influence certain biological processes at different levels of cellular regulation. This review discusses the potential of the chemical reprogramming of RPE cells in comparison with other somatic cells and induced pluripotent stem cells (iPSCs) into neural cells of the brain and retina. Possible mechanisms of the chemically induced reprogramming of somatic cells under the influence of small molecules are explored and compared. This review also considers other possibilities in using them in the treatment of retinal degenerative diseases based on the protection, preservation, and support of survived RPE and retinal cells. Full article

Stroke is one of the leading causes of chronic disability in humans. It has been proposed that the endogenous neural stem/progenitor cells generate new neurons in the damaged area. Still, the contribution of these cells is negligible because a low number of newborn mature neurons are formed. Tlx conventional knock-out mice, Tlx-CreERT2 mice, and Tlx-overexpressing (Tlx-OE) mice were specifically chosen for their unique genetic characteristics, which were crucial for the experiments. Permanent and transient middle cerebral artery occlusion was used to induce stroke in the mice. Immunostainings for doublecortin and GFP/BrdU/NeuN were performed to study neurogenesis and fate mapping. The rotarod test was performed to assess motor deficits. Here, we show that stroke-induced neurogenesis is dramatically increased with the additional expression of two copies of the nuclear receptor-coding gene tailless (Tlx, also known as Nr2e1), which has been shown to be a master regulator of subventricular zone (SVZ) neural stem cells (NSCs). We show that Tlx expression is upregulated after stroke, and stroke-induced neurogenesis is blocked when Tlx is inactivated. Tlx overexpression in NSCs leads to massive induction of neurogenesis via stroke. More newborn mature neurons are formed in Tlx-overexpressing mice, leading to improved coordination and motor function recovery. Most importantly, we also demonstrate that this process is sustained in aged mice, where stroke-induced neurogenesis is nearly undetectable in wild-type animals. This study provides the first stem cell-specific genetic evidence that endogenous NSCs can be exploited by manipulating their master regulator, Tlx, and thus suggests a novel therapeutic strategy for neuronal repair. Full article

Direct pro-neural reprogramming is a conversion of differentiated somatic cells to neural cells without an intermediate pluripotency stage. It is usually achieved via ectopic expression (EE) of certain transcription factors (TFs) or other reprogramming factors (RFs). Determining the transcriptional changes (TCs) caused by particular RFs in a given cell line enables an informed approach to reprogramming initiation. Here, we characterized TCs in the human fibroblast cell line LF1 on the 5th day after EE of the single well-known pro-neural RFs NGN2, ASCL1, SOX2, and MSI1. As assessed by expression analysis of the bona fide neuronal markers nestin and beta-III tubulin, all four RFs initiated pro-neuronal phenotype conversion; analysis by RNA-seq revealed striking differences in the resulting TCs, although some pathways were overlapping. ASCL1 and SOX2 were not sufficient to induce significant pro-neural phenotype switches using our EE system. NGN2 induced TCs indicative of cell phenotype changes towards neural crest cells, neural stem cells, mature neurons, as well as radial glia, astrocytes, and oligodendrocyte precursors and their mature forms. MSI1 mainly induced a switch towards early stem-like cells, such as radial glia. Full article

Alzheimer’s disease is a progressive neurodegenerative disorder characterized by mitochondria dysfunction, accumulation of beta-amyloid plaques, and hyperphosphorylated tau tangles in the brain leading to memory loss and cognitive deficits. There is currently no cure for this condition, but the potential of stem cells for the therapy of neurodegenerative pathologies is actively being researched. This review discusses preclinical and clinical studies that have used mouse models and human patients to investigate the use of novel types of stem cell treatment approaches. The findings provide valuable insights into the applications of stem cell-based therapies and include the use of neural, glial, mesenchymal, embryonic, and induced pluripotent stem cells. We cover current studies on stem cell replacement therapy where cells can functionally integrate into neural networks, replace damaged neurons, and strengthen impaired synaptic circuits in the brain. We address the paracrine action of stem cells acting via secreted factors to induce neuroregeneration and modify inflammatory responses. We focus on the neuroprotective functions of exosomes as well as their neurogenic and synaptogenic effects. We look into the shuttling of mitochondria through tunneling nanotubes that enables the transfer of healthy mitochondria by restoring the normal functioning of damaged cells, improving their metabolism, and reducing the level of apoptosis. Full article

N-methyl-D-aspartate receptors (NMDARs) are critical components of the mammalian central nervous system, involved in synaptic transmission, plasticity, and neurodevelopment. This review focuses on the structural and functional characteristics of NMDARs, with a particular emphasis on the GRIN2 subunits (GluN2A-D). The diversity of GRIN2 subunits, driven by alternative splicing and genetic variants, significantly impacts receptor function, synaptic localization, and disease manifestation. The temporal and spatial expression of these subunits is essential for typical neural development, with each subunit supporting distinct phases of synaptic formation and plasticity. Disruptions in their developmental regulation are linked to neurodevelopmental disorders, underscoring the importance of understanding these dynamics in NDD pathophysiology. We explore the physiological properties and developmental regulation of these subunits, highlighting their roles in the pathophysiology of various NDDs, including ASD, epilepsy, and schizophrenia. By reviewing current knowledge and experimental models, including mouse models and human-induced pluripotent stem cells (hiPSCs), this article aims to elucidate different approaches through which the intricacies of NMDAR dysfunction in NDDs are currently being explored. The comprehensive understanding of NMDAR subunit composition and their mutations provides a foundation for developing targeted therapeutic strategies to address these complex disorders. Full article

Alzheimer’s disease (AD) is a global health concern and the leading cause of dementia in the elderly. The prevalence of this neurodegenerative condition is projected to increase concomitantly with increased life expectancy, resulting in a significant economic burden. With very few FDA-approved disease-modifying drugs available for AD, there is an urgent need to develop new compounds capable of impeding the progression of the disease. Given the unclear etiopathogenesis of AD, this review emphasizes the underlying mechanisms of this condition. It explores not only well-studied aspects, such as the accumulation of Aβ plaques and neurofibrillary tangles, but also novel areas, including glymphatic and lymphatic pathways, microbiota and the gut–brain axis, serotoninergic and autophagy alterations, vascular dysfunction, the metal hypothesis, the olfactory pathway, and oral health. Furthermore, the potential molecular targets arising from all these mechanisms have been reviewed, along with novel promising approaches such as nanoparticle-based therapy, neural stem cell transplantation, vaccines, and CRISPR-Cas9-mediated genome editing techniques. Taking into account the overlap of these various mechanisms, individual and combination therapies emerge as the future direction in the AD strategy. Full article