Search Results (1,373)

Accumulation of aggregated amyloid beta (Aβ) species is a defining pathological hallmark of Alzheimer’s disease and is associated with extensive neuronal structural abnormalities. Mild cognitive impairment (MCI), a transitional stage between normal aging and the onset of dementia, is thought to represent an early phase of this pathological continuum. Studies at the cellular level suggest that the conditions impair the maintenance of established neuronal processes/networks and restrict their capacity for elongation or re-elongation. They may also attenuate the activation and process extension of quiescent neural progenitor or stem-like cells. These early cellular changes precede overt neurodegeneration in neural tissue and are likely to contribute to cognitive decline. They highlight the importance of in vitro models for identifying molecular targets involved in recovery from disease. In this study, we investigated the effects of aggregated Aβ (25–35) on neuronal process elongation and associated intracellular events in the N1E-115 cell line, a widely used model of neuronal differentiation. Addition of aggregated Aβ to cultured N1E-115 cells attenuated process elongation in a concentration-dependent manner. This morphological impairment was accompanied by decreased expression of neuronal differentiation markers. In contrast, at the half-maximal inhibitory concentration for process elongation, long-term cultured cells did not exhibit apparent process retraction or degenerative morphology. This mild but progressive impairment, without extensive cell death, is consistent with the cellular features of early-stage conditions rather than advanced Alzheimer’s pathologies. Similar results were observed in primary cortical neurons. Aβ also decreased the level of GTP-bound Ras and phosphorylation of the downstream mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/ERK). Furthermore, treatment with hesperetin, a bioactive flavonoid compound, recovered the Aβ-induced inhibition of neuronal process elongation. Hesperetin also restored Ras and MAPK/ERK states, suggesting that its effects are associated, at least in part, with modulation of signaling through Ras and MAPK/ERK. Our findings suggest that hesperetin may serve as a useful molecular probe for modulating early cellular responses associated with Alzheimer’s disease-related pathology. This in vitro model might serve as a useful platform for investigating the molecular target candidates involved in recovery from nervous system disorders. Full article

Background: Synaptic plasticity in neurodegenerative disorders (NDs), cognitive impairment, and mental health conditions is regulated by brain-derived neurotrophic factor (BDNF). Even healthy individuals have different levels, which are affected by complex epigenetic, inflammatory, and metabolic regulation. BDNF expression changes are associated with both typical and abnormal aging, as well as mental health conditions. These changes affect brain areas that are crucial for memory, such as the hippocampus and the parahippocampal cortex. Neurotrophins (NTs), including nerve growth factor (NGF) and BDNF, are essential for neuronal differentiation via tropomyosin receptor kinase B (TrkB) and the p75 neurotrophin receptor (p75NTR). Dysregulated NTs signaling contributes to synaptic dysfunction and neuroinflammation. Objective: This systematic review synthesizes preclinical evidence of the potential of naturally derived compounds to modulate NTs for neuroprotection and their incorporation into novel foods. Methodology: A review of major databases found studies that examined the impact of dietary polyphenols and other bioactive substances on NT signaling oxidative stress, inflammation, and neuronal plasticity. Results: Compounds such as epigallocatechin gallate, resveratrol, curcumin, quercetin, and flavanols, can positively impact NTs, reducing reactive oxygen species/reactive nitrogen species, enhancing cell survival, and increasing the expression of trophic factors such as nuclear factor erythroid 2-related factor 2 (Nrf2), NGF, and vascular endothelial growth factor in neural stem cells. However, their bioavailability, optimal dosage, and dietary interactions require further research. Conclusions: The consumption of BDNF-promoting foods can potentially stimulate BDNF synthesis, support optimal neurotransmission, and fortify neural plasticity. Evidence supports a polyphenol-rich diet for preventing NDs and promoting brain health. Observational studies consistently support the protective effects of polyphenols on brain health through their impact on the gut–brain axis. Full article

Oligodendrocytes (OLs) are essential for myelin formation in the central nervous system, and their loss or dysfunction is a hallmark of various demyelinating and neurodegenerative disorders. Although oligodendrocyte precursor cells (OPCs) represent a promising cell source for remyelination therapies, existing protocols for generating OPCs from human-induced pluripotent stem cells (iPSCs) are often limited by prolonged culture duration, low efficiency, and cellular heterogeneity. Here, we report an efficient and reproducible platform for generating OPCs from iPSC-derived neural progenitor cells (iNPCs) through stage-specific modulation of developmental signaling pathways. Directed differentiation of iNPCs recapitulated key developmental transitions, progressing through OLIG2⁺/NKX2.2⁺ progenitors to CD140a⁺/O4⁺ OPCs within a significantly shortened timeframe compared to conventional approaches. Notably, iNPC-derived spheres functioned as a progenitor-like niche, enabling sustained OPC production through serial replating. Purified OPCs could differentiate into MBP⁺ oligodendrocytes and demonstrated myelination capacity both in vitro, via nanofiber ensheathment and in vivo following transplantation into shiverer (shi/shi) mice, where they formed myelin sheaths around host axons. Despite these advances, OPC differentiation and maturation efficiencies remained suboptimal, highlighting the need for further optimization. Collectively, our findings establish a scalable and time-efficient strategy for iPSC-derived OPC generation and underscore their potential for disease modeling and cell-based remyelination therapies. Full article

Objectives: Alzheimer’s disease (AD) is associated with impaired adult hippocampal neurogenesis (AHN). This study aimed to establish an in vitro model of Aβ_1–42 oligomer-damaged neural stem cells (NSCs) and to employ the 5×FAD mouse model of AD in vivo, and to evaluate the therapeutic effects of brain-derived neurotrophic factor-loaded hyaluronic acid hydrogel (BDNF-HA gel) on AHN. Methods: In vitro, BDNF-HA gel was co-cultured with Aβ_1–42 oligomer-impaired NSC spheres and evaluate NSC proliferation, migration, and differentiation. In vivo, BDNF-HA gel was infused intracerebroventricularly into 5×FAD mice. Using BrdU labeling, immunofluorescence, anterograde transsynaptic viral tracing, and behavioral tests, we assessed the effects of BDNF-HA gel on adult neurogenesis, newborn neuron integration into memory circuits, and cognitive function. Results: In vitro, BDNF-HA gel attenuated Aβ_1–42-induced NSC apoptosis, restored proliferation and migration, promoted differentiation into neuroblasts, newborn neurons, and oligodendrocytes, and alleviated mitochondrial depolarization and loss of mitochondrial mass. In vivo, despite the absence of significant Aβ plaques reduction in 5×FAD mice, BDNF-HA gel markedly enhanced NSC proliferation and neurogenesis in the subventricular zone (SVZ) and subgranular zone (SGZ). Behavioral tests further revealed significant improvements in object recognition, spatial working memory, and spatial reference memory. Conclusions: BDNF-HA gel can effectively counteract the toxic microenvironment induced by Aβ oligomers, promoting NSC proliferation, migration, and differentiation into neurons. Without altering the Aβ burden, it significantly enhances adult neurogenesis and rescues cognitive deficits in AD mice. Full article

Temporal lobe epilepsy (TLE) is a common drug-resistant epilepsy characterized by recurrent seizures, cognitive impairment, aberrant adult hippocampal neurogenesis, inhibitory circuit disruption, and persistent inflammatory remodeling. Current anti-seizure medications primarily offer symptomatic control and do not target the progressive structural and functional deterioration of epileptic hippocampal networks. Here, we investigated whether local nerve growth factor (NGF)-hydrogel delivery during the latent phase after status epilepticus could mitigate hippocampal pathological remodeling and improve long-term outcomes in a kainic acid (KA)-induced mouse model (utilizing C57BL/6J and Nestin-CreERT2 mice). Animals were randomly assigned to three groups: the saline control group, the untreated KA epilepsy group, and the KA + NGF-hydrogel treatment group. NGF-hydrogel was administered into hippocampal Cornu Ammonis 1 (CA1) beginning 3 days post-kainic acid and repeated every 15 days. Histological, immunofluorescence, circuit-tracing, electrophysiology, electroencephalography (EEG), and behavioral assessments were used to evaluate neurogenesis, microenvironment, circuit readouts, seizure burden, and cognition. NGF-hydrogel treatment was associated with preserved dentate gyrus neural stem cell populations, improved newborn granule cell localization and maturation, attenuated neuroinflammation and gliosis, and partial recovery of inhibitory interneuron markers. These changes were accompanied by improved hippocampal circuit readouts, reduced chronic spontaneous seizure burden, and enhanced recognition and spatial memory. Our findings indicate that local NGF-hydrogel delivery following status epilepticus is associated with improved hippocampal remodeling and functional outcomes, and suggest that biomaterial-based neurotrophic support may be a promising strategy for providing targeted neuroprotection and facilitating excitatory/inhibitory (E/I) balance reconstruction in the epileptic hippocampus. Full article

Current protocols for generating cortical interneurons from human pluripotent stem cells are hindered by slow differentiation kinetics and poor reproducibility across cell lines. Here, we present a defined small-molecule-based strategy that efficiently directs human-induced neural stem cells (hiNSCs) toward cortical GABAergic interneurons within 14–18 days, which is substantially faster than conventional methods. Short-term dual-SMAD and WNT inhibition rapidly commits hiNSCs to an interneuron progenitor fate, reaching transcriptional states equivalent to those obtained with prolonged protocols. Prolonged activation of Sonic Hedgehog (via SAG) further enhances lineage specification, markedly upregulating NKX2.1, FOXG1, GABA, somatostatin (SST), and parvalbumin (PV) expression, and enriching pathways associated with early functional maturation. Importantly, RNA-sequencing reveals that under identical induction conditions, hiNSCs differentiate more rapidly and homogeneously than human-induced pluripotent stem cells (hiPSCs), which exhibit broader, less lineage-focused transcriptional trajectories. This differentiation strategy is highly reproducible across four genetically distinct hiNSC lines, with minimal off-target populations. Functionally, hiNSC-derived cortical interneurons display robust migratory behavior, produce abundant GABA, and survive transplantation into the adult mouse hippocampus, where they extend processes and form synapse-like structures. These findings establish a rapid, scalable, and robust approach for generating human cortical interneurons, supporting their safety and integration potential as a foundation for future cell replacement strategies in neurological disorders. Full article

Background/Objectives: Stroke remains the second leading cause of death worldwide, and cell therapy is among the most actively investigated strategies for its treatment. Recent transcriptomic evidence has revealed that 293T cells—the most widely used transient transfection model—possess a neural crest/neuronal lineage, making them a candidate for acute neural tissue engineering. Methods: We implanted iron oxide nanoparticle-labeled 293T cells (293T-ION) into an ischemic rat brain and monitored them longitudinally by 7T MRI, using ION-labeled bone marrow-derived mesenchymal stem cells (rMSC-ION) as a direct comparison. Functional recovery was assessed via mNSS and corner test scores, and infarct size was quantified by MRI. Results: 293T-ION cells showed no migration throughout the 40-day observation period, and functional recovery plateaued early compared with the progressive improvement seen with rMSC-ION. 293T cell implantation provoked pronounced, localized CD68-positive microglial hyperactivation at both implantation and ischemic sites, without migration toward the choroid plexus (CP). In contrast, rMSC-ION actively migrated to the CP and drove superior neuroplasticity marker expression (Ki67, Nestin, NeuN). Conclusions: 293T cells produce transient localized microglial activation and limited brain plasticity, whereas rMSCs drive sustained neurorestoration. Synergistic co-administration of these cell types may represent a future therapeutic strategy bridging hyper-acute and chronic recovery phases. Full article

Intraperitoneal (I.P.) delivery of cell-based therapeutics represents a promising strategy for treating regional peritoneal diseases; however, rapid cellular clearance severely limits therapeutic durability. A critical unmet need is the development of implantable biomaterial platforms that can both mechanically integrate within the dynamic I.P. cavity and sustain viable cell persistence in vivo. Here, we establish a Continuous Liquid Interface Production (CLIP)-based 3D bioprinting strategy to engineer transplantable, cell-laden hydrogel scaffolds optimized for I.P. implantation. Through systematic bioresin design, we identify a GelMA-PEGDA formulation that achieves a balance between high-resolution printability, tissue-matched mechanical characteristics (Young’s modulus 10–15 kPa), and controlled biodegradation (~75% mass loss over 14 days). The resulting constructs support sustained cell viability and proliferation for over 30 days in vitro. Importantly, in an animal study conducted in 6–8 weeks of female nude mice, in vivo I.P. implantation demonstrates a ~10-fold extension in cellular persistence compared to direct cell injection, prolonging the time to 50% signal decay from ~3 days to ~30 days, with detectable cell retention approaching two months in select animals. The platform further accommodates multiple clinically relevant cell types, including human mesenchymal stem cells and neural stem cells, highlighting its translational versatility. Collectively, this work defines key material and architectural parameters required for I.P. implantable cell therapeutics and establishes CLIP-based bioprinting as a scalable strategy for regional delivery of living therapeutics. Full article

Neuroblastomas (NBs) are aggressive, therapy-resistant embryonal tumors of neural crest origin, which despite low mutational burdens exhibit high intra-tumoral heterogeneity characterized by adrenergic, noradrenergic, mesenchymal and cancer stem cell (CSC)-like subpopulations. These phenotypes exhibit interconverting plasticity that reflect both stage of transformation during sympathoadrenal development and conditions within the tumor microenvironment. Chemotherapeutic agents promote adrenergic-to-mesenchymal conversion in NBs, which underpins drug resistance, post-therapeutic relapse, metastatic progression, and the plateauing of responses to advances in multimodal therapy. Improved understanding of the molecular mechanisms that regulate NB phenotypic plasticity is essential for identifying novel prognostic markers and potential therapeutic targets. In this article, following introductions into NB, molecular regulation of NB phenotypic plasticity, and the NF-Y transcription factor and its role in development and differentiation, we focus on alternative NF-YAl, NF-YAs and NF-YAx splicing of the NF-Y subunit, NF-YA, and the potential influence that different NF-YA isoforms have on NF-Y function and the NF-Y-transcription factor networks that impact NB cell phenotypes. Particular attention is paid to the novel extra short-form NF-YAx isoform, originally detected as the exclusive NF-YA isoform in a non-MYCN amplified advanced stage 3 NB. This isoform is also induced by doxorubicin in non-Myc amplified SH-SY5Y NB cells and is involved in doxorubicin cytotoxicity. Despite high cytotoxicity, however, NF-YAx selects a resistant subpopulation with mesenchymal/neural crest stem cell-like identity, unveiling a doxorubicin-induced NF-YAx-dependent resistance mechanism, with potential to influence post-therapeutic relapse and disease progression. Therefore, evaluating alternative NF-YA splicing, and especially NF-YAx expression, in advanced stage and post-therapeutic relapsed NBs, may be of both prognostic and therapeutic significance. Full article

Demyelinating diseases are characterized by loss of myelin and impaired neuronal function. Differentiation of oligodendrocyte progenitor cells (OPCs) and neural stem and progenitor cells is regulated by intracellular kinase signaling pathways. PI3K/Akt/mTOR and Wnt/GSK-3β signaling are involved in oligodendrocyte maturation and neurogenesis, and pharmacological modulation of these pathways affects myelin formation and neuronal differentiation. Small-molecule compounds targeting these pathways influence protein synthesis, lipid production, and β-catenin-dependent transcription. Activation of Akt and mTOR is associated with increased myelin-related protein expression, whereas inhibition of mTOR reduces oligodendrocyte differentiation. In contrast, inhibition of GSK-3β affects β-catenin stability and is associated with oligodendrocyte differentiation. These pathways also affect proliferation and differentiation of neural stem and progenitor cells. However, effects observed in experimental demyelination models have not been established as direct evidence of remyelination in patients. In addition, pharmacological agents act on multiple cell populations in the central nervous system (CNS), which complicates interpretation of their effects on specific cell types. This review examines pharmacological targeting of PI3K/Akt/mTOR and Wnt/GSK-3β signaling and describes intracellular mechanisms involved in oligodendrocyte and neuronal differentiation, with consideration of therapeutic application in demyelinating diseases. Full article

The heterogenous mesenchymal stem/stromal cells (MSCs) express the surface antigens associated with distinct cell subpopulations. CD271, characteristic of stem cells derived from the neural crest, could indicate cells with a unique phenotype. The study examined whether the CD271+ subpopulation characterized by better stem and neural properties than the heterogeneous MSC population. The initial Wharton jelly-derived MSCs (WJ-MSCs) population was divided into two subpopulation: CD271-positive (WJ-MSC-CD271+) and CD271-negative (WJ-MSC-CD271−) with Fluorescence-Activated Cell Sorting (FACS). We compared the clonogenic potential and neural marker expression under standard culture conditions and in the presence of nerve tissue components—cerebrospinal fluid (CSF) or nerve tissue fragments (hippocampus). FACS allowed the enrichment of CD271+ cells from 1% to approximately 50%. WJ-MSC-CD271+ is characterized by significantly more self-renewal cells and increased expression of neuronal genes than WJ-MSC-CD271−. Under co-culture with CSF or hippocampal fragments, WJ-MSC-CD271+ contained more cells expressing Β-III-tubulin as well. Finally, we reported that stimulation with epithelial growth factor (EGF) and basal fibroblast growth factor (bFGF) enhanced CD271+ numbers in the initial population and stabilized them in further cell culture. WJ-MSC-CD271+ cells showed improved potential for differentiation into neural progenitors, although further research is needed for their potential use in neurological diseases. Full article

Progranulin (PGRN) is a secreted protein composed of 7.5 granulin domains. The protein is implicated in various functions, including cell survival, inflammation, lysosomal homeostasis, tumorigenesis, and aging. Haploinsufficiency and complete loss of PGRN function cause the neurodegenerative disorders frontotemporal lobar degeneration and neuronal ceroid lipofuscinosis type 11, respectively. In the nervous system, administration of exogenous PGRN has been shown to promote the survival of various nerve cell types under different pathological conditions and to stimulate neurite outgrowth in vitro and axonal regeneration in vivo. In the retina, PGRN dysfunction results in photoreceptor and retinal ganglion cell (RGC) loss, whereas PGRN administration promotes photoreceptor cell survival. In the present study, we analyzed whether a sustained intravitreal administration of PGRN promotes the survival of axotomized RGCs and the regrowth of the lesioned axons. To this end, we generated a PGRN-overexpressing clonal neural stem cell line and injected the cells into the vitreous cavity of a mouse optic nerve crush model. The progression of the lesion-induced degeneration of RGCs was studied at different time points after the nerve crush. The regeneration of the injured RGC axons into the distal optic nerve stump was analyzed one month after nerve lesioning. We found that the intravitreally administered PGRN slowed the degeneration of the injured RGCs for up to four months, the latest post-lesion interval analyzed. Furthermore, PGRN stimulated the regeneration of some RGC axons over long distances into the distal optic nerve stumps. Taken together, our results identify PGRN as a novel neurotrophic factor for retinal ganglion cells. Full article

Mesenchymal stem/stromal cells (MSCs) hold promise for treating different equine conditions but enter senescence during culture. Using induced pluripotent stem cells (iPSCs) to derive MSC-like cells (iMSCs) can increase cell availability and diminish the need for invasive and repeated tissue harvesting. While human iMSCs are intensively studied, research on equine iMSCs (eqiMSCs) is very limited and has focused on strategies for spontaneous differentiation to obtain these cells. The aim of this study was to obtain MSC-like cells from equine iPSCs (eqiPSCs) by directing their differentiation via the neural crest pathway. The resulting eqiMSCs downregulated pluripotent gene expression compared to originating eqiPSCs, and the majority of lines met most of the standard criteria for tissue-derived MSCs (immunophenotype and tri-lineage differentiation potential). Nevertheless, eqiMSCs showed some differences from primary equine MSCs, possibly due to their different developmental origin, and displayed certain inter-line variability, which might be related to the different kinetics of independent eqiPSC lines. This study demonstrates for the first time that equine MSC-like cells (eqiMSCs) can be derived from eqiPSCs by directing their differentiation through the neural crest pathway. This constitutes an important advancement towards more sustainable sources of therapeutic cells in veterinary medicine and warrants further exploration of the functional characteristics of these novel cells. Full article

Thyroid hormones (THs) are essential regulators of human brain development, and disrupted TH availability during pregnancy or early life is linked to adverse neurodevelopmental outcomes. Concerns that environmental chemicals interfere with TH signalling have increased the need for human-relevant in vitro systems to identify thyroid hormone system-disrupting chemicals (THSDCs) for risk assessment. Here, we compared two human-induced pluripotent stem cell (hiPSC)-derived brain organoid models for THSDC assessment: (i) human cortical organoids (COs) generated by unguided differentiation, offering higher architectural complexity but lower throughput; and (ii) neural stem cell-derived organoids (NSCOs), designed for scalability with reduced cellular diversity. Both models expressed key TH handling components, including the transporter SLC16A2 (MCT8) and the inactivating enzyme DIO3. Using LC–MS/MS, we show that exogenous T3 is depleted from culture media and metabolized to 3,3′-T2 and 3′-T1 in both models, alongside upregulation of T3-responsive genes (HR, KLF9, DIO3, SEMA3C). Pulse and chronic co-exposures to reference disruptors iopanoic acid (IA, deiodinase inhibitor) and silychristin (SC, MCT8 inhibitor) altered T3 metabolism and modulated T3-responsive transcriptional endpoints. In NSCOs, high-content imaging revealed treatment-associated changes in cell composition, with chronic T3 reducing the SOX2-positive progenitor pool and THSDCs blocking this effect. Together, these findings provide a framework for organoid qualification—linking TH handling, transcriptomic responsiveness, and scalable phenotypic readouts—as a necessary step toward model validation and implementation of brain organoids in THSDC risk assessment pipelines. Full article

Background: Human dental pulp stem cells (hDPSCs) are a promising source of multipotent mesenchymal stem cells (MSCs) for regenerative neurology because of their inherent neurogenic potential. However, robust and reproducible protocols for driving their terminal neuronal maturation in a fully defined, xeno-free environment are lacking. Methods: hDPSCs were isolated from a donor tooth and characterized for mesenchymal (CD105, CD90, CD73, CD13) and stemness-associated markers (SOX2, Oct3/4 and Nanog). Cells were differentiated in a novel, fully chemically defined medium 1% ITS medium (ITS: Insulin, Transferrin, Selenium) supplemented with glial cell line-derived neurotrophic factor (GDNF) or brain-derived neurotrophic factor (BDNF). Neuronal commitment and partial maturation were assessed via immunofluorescence, Western blot, and RT-PCR for markers such as NeuN (Neuronal nuclei) and NF-M (Neurofilament medium chain), and functionally by whole-cell patch-clamp electrophysiology. Results: Although undifferentiated hDPSCs expressed neural progenitor markers (βIII-tubulin and Nestin), only GDNF treatment in a chemically defined medium significantly upregulated mature neuronal markers (NeuN and NF-M) and downregulated mesenchymal markers. Importantly, GDNF-treated cells exhibited key functional changes, including hyperpolarized resting membrane potentials, increased membrane capacitance, and elevated input resistance, which are electrophysiological hallmarks of neural precursor or early neuronal maturation, compared to control cells cultured in medium containing fetal bovine serum (FBS). Although action potentials were not elicited, this represents a significant advancement toward achieving a functional neuronal state. Conclusion: This study demonstrates that a fully chemically defined medium enables GDNF to drive hDPSCs beyond the neural progenitor state towards a partially mature neuronal phenotype. This defined medium protocol eliminates serum variability, enhances reproducibility, and provides a critical step towards standardizing hDPSC-derived neuronal cells for disease modeling and cell-based therapy. Full article