Search Results (945)

Animal studies have shown that early life exposure to general anesthetics may impair brain development. However, the implications of this phenomenon in human patients remain unclear. In this study, we use an induced pluripotent stem cell (iPSC)-derived human brain microphysiological system (bMPS) to investigate the effects of early sevoflurane (SEV) exposure on human brain development. Human iPSCs were cultured and differentiated into neural progenitor cells (NPCs) and then into bMPS. At week 8, bMPSs were exposed to 2.4% SEV for 4 h. Four weeks after exposure, immunofluorescence (IF), Western blotting (WB), and quantitative real-time polymerase chain reaction (qPCR) were conducted to evaluate the alteration of nerve cells in bMPS. After SEV exposure, the number of apoptotic cells increases, and the level of neural differentiation markers decreases. The ratios of mature neurons over NPCs and mature oligodendrocytes over oligodendrocyte progenitor cells (OPCs) are reduced, which leads to a reduction in myelination. SEV also impedes the development of astrocytes and synaptogenesis, especially the formation of excitatory synapses. Meanwhile, SEV increases the expression of molecules in the mammalian target of rapamycin (mTOR) signal pathway. In conclusion, early SEV exposure substantially disrupts the development of human brain tissue, and the mTOR signal pathway is likely to be involved in this alteration. Full article

Background and objectives: Movement disorders are an underrecognized phenomenon in Myelin Oligodendrocyte Glycoprotein-Associated Disease (MOGAD). The aim of this paper was to summarize all movement disorders previously described in MOGAD. Materials and Methods: We conducted a systematic literature search in PubMed, Web of Science, and Scopus in English, focusing on patients with MOGAD exhibiting a movement disorder, i.e., ataxia, tremor, dystonia, parkinsonism, chorea, athetosis, myoclonus, ballism, tics, stereotypies, dyskinesia. Results: We included 58 studies, with a total of 91 patients with MOGAD and a movement disorder (45.6% male, 54.4% female). Movement disorders had a mean latency of 2.1 years (±6.9, 0–42) after MOGAD onset; however, they could be the presenting feature (in approximately 70% of cases), especially in pediatric patients. Cerebellar ataxia was the most common movement disorder, occurring in 77 patients (84.6%). Tremor, postural and/or kinetic, was the second most common movement disorder (15%). Dystonia was reported in 8.8%, presenting as cervical, or limb dystonia or stereotyped dystonic episodes. Myoclonus and hypokinetic movement disorders were rare. Subcortical (in 60%), brainstem and cerebellar lesions (in 50% respectively) were the most common imaging findings. The most common accompanying symptoms were encephalopathy, fever and headache. Approximately half of the patients made a full recovery, and the other half showed a significant improvement in the movement disorder after immunomodulatory treatment, most commonly steroids. Conclusions: The new onset of a movement disorder, especially ataxia, in a young patient should prompt the search for MOGAD or can indicate a relapse in patients with an established diagnosis. Full article

Background/Objectives: Fetal alcohol spectrum disorders (FASDs) occur in nearly 5% of children in the United States and have been associated with alterations in neurological functions, neuroanatomical changes, and behavioral deficits encompassing an individual’s lifetime. Alterations in myelination have been reported in both rodent models and humans. The cerebellum is a heavily myelinated brain region, and oligodendrocyte and myelination transcripts have been reported to be altered in the cerebellum following early-life ethanol (EtOH) exposure in a mouse model. In this study, we investigated cerebellar-recruited behaviors in adult female mice that were exposed to EtOH from postnatal day (P) 4 to P9. We investigated whether changes in oligodendrocyte lineage markers were present in adulthood. Methods: C57BL/6J offspring received a total of 5.0 g/kg/day of either ethanol (EtOH) or saline in two separate doses delivered subcutaneously two hours apart from P4 to P9. On P21, offspring were weaned and housed with same-sex littermates throughout the duration of the study. From P60 to P90, females underwent behavioral testing including an open field test (OFT), rotarod, and balance beam. Behavior naïve littermates were euthanized on P105, and cerebella were collected for qPCR to assess oligodendrocyte lineage transcripts. Results: We reported that, following EtOH exposure from P4 to P9, adult female mice had increased ambulatory behaviors in the OFT and subtle changes in behavior in the rotarod and balance beam compared to saline-exposed controls. Despite the behavioral changes observed in adulthood, we found that alterations in oligodendrocyte lineage transcripts present on P10 did not persist into adulthood. Conclusions: Subcutaneous injection of EtOH from P4 to P9 resulted in long-term consequences in locomotor and cerebellar-recruited behaviors in female mice. Full article

Background: Apigenin, as a flavonoid, can be protective against oxidative damage in hypoxic events due to its antioxidant properties. Here, we have investigated the neuroprotective effects of apigenin in an ex vivo model of ischemic damage, using cerebellar slices from postnatal day (P)8–12 reporter mice to identify oligodendrocytes (SOX10-EGFP) and astrocytes (GFAP-EGFP). Methods: Apigenin (10 and 20 μM) was administered preventively at 60 min prior to and during inducing ischemic damage by oxygen and glucose deprivation (OGD); controls were maintained with glucose and normoxia (OGN). Results: OGD induced a marked retraction of oligodendroglial processes without reducing the oligodendrocyte number. This structural disruption was prevented by apigenin; notably, 10 μM apigenin blocked process retraction, whereas 20 μM did not, indicating a dose-dependent effect on the oligodendroglial morphology. Consistent with this, MBP and NF70 immunofluorescence analyses of axonal myelination demonstrated that OGD caused a significant loss of myelin sheaths, and this was prevented by pre-treatment with apigenin. In addition, apigenin prevented astrocyte reactivity induced by OGD, as assessed by increased GFAP-EGFP expression and decreased expression of glutamine synthetase. Moreover, immunofluorescence for calbindin indicated that apigenin protected Purkinje neurons from ischemic damage. Conclusions: These results demonstrate that apigenin is neuroprotective in ischemia and this is associated with modulation of astrocyte reactivity and maintenance of oligodendrocyte and myelin integrity. Full article

Loss of myelinating oligodendrocytes and myelin impairs motor and cognitive functions. Transplantation of autologous oligodendrocyte precursors (OPCs) holds promise for treatment of such diseases, but a protocol to derive human OPCs from a safe, ethical and accessible cell source with the rapidity required to catch the therapeutic window remains to be found. Although we previously generated myelinating glia from rat bone marrow stromal cells (BMSCs), it remains unknown if clinically sourced human BMSCs (hBMSCs) share the same potential. Moreover, whether the multipotency of BMSCs results from diverse progenitors preexisting in the bone marrow or from a single multipotent progenitor population remains unaddressed. Single-cell RNA sequencing data revealed a CD90^hiEGFR⁺PDGFRA⁺ pre-OPC-like subpopulation within hBMSCs. With a small-molecule-based (virus-free and supporting-cell-free) two-step induction protocol designed to expand this pre-OPC population, we generated functional OPCs with high purity in eight days. These derived OPCs showed phenotypic transcriptomes and immunoprofiles. They were also capable of myelinating naked axons when transplanted into myelin-deficient shiverer mice. Results highlight how targeted enrichment and maturation of specific progenitor subpopulations within hBMSCs allows rapid induction of desired cell types. These results place hBMSCs as a robust source of OPCs, unlocking the possibility for cell transplantation therapy for myelin deficiency in the central nervous system. Full article

Glioblastoma (GBM) remains one of the most lethal cancers, and despite advancements in understanding its underlying molecular signature, effective therapeutics are still lacking. The multifaceted challenges of designing treatments for GBM are compounded by the inability to identify a definitive cell of origin, the understanding of which is crucial for developing impactful therapies and ultimately improving patient outcomes. High-resolution technologies, including single-cell and single-nucleus RNA sequencing, spatial transcriptomics, multi-omics, next generation glioma models, bioinformatics, and artificial intelligence are creating an important opportunity to comprehensively map the cellular origin of GBM and its evolutionary dynamics. Accumulating evidence support neural stem cells (NSCs) and oligodendrocyte precursor cells (OPCs) as primary candidates, providing critical insights into the ontogeny of GBM. This comprehensive review synthesizes current knowledge on the cellular origins of GBM and evaluates advanced methodologies, deepening our understanding of its development. Full article

The ontological categorization of the cellular elements of the brain was proposed over a century ago by Santiago Ramón y Cajal (neurons, astroglia) and Pío del Río-Hortega (oligodendroglia, microglia). It combines histochemical observations of morphology with allied inferences about the specialized functions and origins (ectoderm or mesoderm) of each cellular element. This ontology shapes modern neuroscience, with the main non-neuronal cells—astroglia, oligodendroglia and microglia—viewed as having distinct primary roles relating respectively to the metabolic support, myelination and immunoprotection of neurons, the information signaling cells. Yet contemporary techniques, ranging from electrophysiology to single-cell transcriptomics and ultrahigh resolution spectroscopy, are revealing intersecting molecular profiles and functional capacities of these cell groups, for example metabolic support, neuroimmune and signaling functions in oligodendroglia. Here we identify discrepancies in current glial paradigms, from empirical, evolutionary and pragmatic perspectives. We suggest a subset of small, iron-rich glial cells, usually with few processes, often viewed as oligodendroglia with myelin-related primary functions, instead have iron-related primary functions that are central to all aspects of brain activity. We call these ‘ferriglia’. We discuss implications for pathogenesis across the spectrum of neuropsychiatric and neurological disorders, including neurodegenerative conditions such as Alzheimer’s disease and other less common cognitive, movement and neurobehavioral disorders, stroke and cerebrovascular disease, glioblastoma and other brain cancers and neuroimmune conditions. We also briefly address the question of where ferriglia may reside within existing glial compartments and lineages, implications for the ontological classification of other glial cells, and research challenges that must be overcome going forward. Full article

From an epidemiological perspective, polymorphous low-grade neuroepithelial tumor (PLNTY) represents a small proportion of brain tumors encountered in epilepsy surgery series. Their rarity and relatively recent recognition likely contribute to underdiagnosis and poor prognosis. In terms of histopathological features, they are similar to oligodendrogliomas. Molecular analyses can be used to show the fusion between fibroblast growth factor receptor (FGFR3) and transforming acidic coiled coil (TACC) proteins, which most commonly results in progression towards glioblastoma (GBM). We report a case of a 62-year-old man who underwent left frontal craniotomy to remove a frontal mass. Histologically, the glial lesion consisted of elements associated with oligodendroglia-like features. Immunohistochemistry was positive for glial fibrillary acidic protein (GFAP), oligodendrocyte transcription factor 2 (OLIG2), and α-thalassemia X-linked mental retardation syndrome (ATRX) nuclear expression, but negative for isocitrate dehydrogenase 1 (IDH1) and BRAF-V600E. Next-generation sequencing showed the FGFR-TACC3 fusion, and taken together, these findings supported the final diagnosis of PLNTY. During follow-up, the patient underwent a second neurosurgery, where histological evaluation indicated a GMB. This article presents clinical and radiological data, morphology, immunohistochemistry, molecular features, and treatment to enhance the clinical and pathological understanding of PLNTY with FGFR3-TACC3 fusion for all professionals involved in medical decisions. Full article

Background: Preterm birth is a leading cause of neonatal mortality and long-term disability worldwide. Injury in premature infants is demonstrated by disrupted organ development from inflammation, oxidative stress, hypoxia, and impaired vascular maturation. Current therapies largely provide supportive care and do not directly promote tissue regeneration. Mesenchymal stem cell (MSC)-based therapies have emerged as a potential strategy to enhance endogenous repair across organ systems commonly affected by prematurity. Results: Evidence indicates that MSCs exert therapeutic effects primarily through transient paracrine signaling rather than long-term engraftment. Following administration, MSCs release cytokines, growth factors, and extracellular vesicles that reduce inflammation, promote angiogenesis, and support tissue repair. In preclinical models of neonatal brain injury, MSC therapy has been associated with improved oligodendrocyte maturation and reduced white matter injury. Early clinical trials in neonatal encephalopathy demonstrate feasibility and short-term safety of both autologous and allogeneic cell products. However, studies remain limited by small sample sizes and short follow-up. Cell-free approaches using MSC-derived extracellular vesicles may offer similar biological benefits with potentially lower safety and regulatory concerns. Conclusions: MSC-based therapies represent a promising regenerative approach for complications of prematurity. Rigorous, large-scale trials with standardized protocols and long-term follow-up are necessary to clarify efficacy, optimize delivery strategies, and define safety in this vulnerable population. Full article

Pharmacological activation of brain Retinoid X Receptors (RXRs) enhances cognition and facilitates amyloid-beta (Aβ) clearance in Alzheimer’s disease (AD) mouse models, partly by upregulating apolipoprotein E (Apoe), a major AD genetic risk factor. However, the specific cellular contributions to these effects are unclear. Here, we used single-cell transcriptomic profiling to investigate cell subpopulation-specific responses to bexarotene, an RXR agonist, in APP/PS1 mice. Our analysis revealed that bexarotene activated cholesterol biosynthesis and lipid metabolism transcriptional programs in homeostatic astrocytes and oligodendrocytes. Astrocytes also upregulated neurodevelopmental genes, while oligodendrocytes and endothelial cells showed enhanced protein folding and cellular growth pathways. Bexarotene further modulated immune responses, promoting Aβ-responsive signatures in disease-associated microglia and reactive astrocytes while dampening pro-inflammatory responses in homeostatic microglia and endothelial cells. Furthermore, Apoe expression was significantly elevated across multiple cell types, especially in microglia and oligodendrocytes. Cell–cell communication analysis highlighted increased astrocyte-centered signaling, with APOE-driven pathways emerging as a prominent mediator. These findings clarify the molecular complexity of RXR-mediated regulation, revealing the cellular origins of bexarotene’s known effects as well as novel, cell-type-specific responses. This study provides mechanistic insights into RXR-targeted interventions and supports APOE-associated pathways as promising therapeutic targets in AD. Full article

Background/Objectives: Methadone maintenance treatment (MMT) is one of the major pharmacotherapies for opioid use disorder. The underlying mechanisms of addiction and the treatment response are only partially understood. The study’s main goal was to identify differential DNA CpG methylation that occurred in response to MMT. Methods: Toward this goal, we have conducted a longitudinal epigenome-wide study of blood samples from 64 patients at the beginning and after 1–3 years of MMT, using a linear mixed model. Results: A total of 1881 differentially methylated probes (DMPs) were identified (FDR < 0.05), controlling for sex, age, estimates of blood cell proportions, and the first two principal components based on genome-wide SNP genotypes. Among the genes annotated to the top DMPs are DGLUCY, NXNL2, SOX10, and NPAS3. Several genes associated with substance use disorder were annotated by the identified DMPs, including ADORA2A, BDNF, CACNA1D, CREB1, CRHR1, CRY1, DNMT3B, GABRD, GNAS, GRIP1, OXR1, PRKACB, SCN2A, and SCN3A. The most overrepresented pathway is the small GTPase-mediated signal transduction pathway, and the most overrepresented process is the actin cytoskeleton organization. Conclusions: The study provides preliminary insight into the epigenetic effect of MMT. Future studies will have to confirm the DMPs, assess their impact on gene expression, and determine their clinical relevance. Full article

Alpha-synuclein (αSyn) is one of the most abundant proteins in the nervous system and is currently associated with devastating synucleinopathies, yet its biology extends far beyond this. In this review, we suggest that αSyn-driven disease emerges within specific neural circuits through the combined effects of cell-type-specific roles, subcellular environments, post-translational modifications (PTMs), and co-pathology. These interacting and additive dimensions, rather than αSyn alone, generate the pathological diversity, shaping whether pathology manifests as Parkinson’s disease (PD), Parkinson’s disease dementia (PDD), dementia with Lewy bodies (DLB), multiple system atrophy (MSA), or mixed dementia phenotypes. We integrate recent advances on the physiological roles of αSyn in neurons and glia (astrocytes, oligodendrocytes, and microglia), its compartment-dependent (e.g., synaptic and nuclear) functions, and the molecular transitions (e.g., mediated by pS129) that convert functional assemblies into pathogenic conformers. Building on this foundation, we outline mechanisms through which these factors contribute to disease-specific vulnerability, progression, and clinical heterogeneity. Finally, we highlight how this multidimensional perspective on αSyn biology can inform the development of next-generation biomarkers that support precision therapies across distinct disorders. Full article

Myelination is essential for rapid axonal conduction and neuronal integrity, and its loss in demyelinating diseases such as multiple sclerosis (MS) leads to progressive neurological impairment. Despite advances in immunomodulatory therapies, effective strategies that promote remyelination remain limited. Here, we identify Morusin, a prenylated flavonoid natural compound, as a potent enhancer of oligodendrocyte (OL) differentiation and myelination-associated outcomes. Using a fluorescence-based screen of diverse flavonoids in primary rat oligodendrocyte progenitor cells (OPCs), it was found that Morusin markedly increased myelin basic protein (MBP) expression. To enable cross-species validation, we established a SOX10-inducible human OPC differentiation system, which shortened differentiation time and allowed functional screening in human cells. In this platform, Morusin enhanced OL maturation and induced a transcriptional profile enriched for myelination- and axon ensheathment-related genes, including MBP, PLP1, MAG, and SIRT2. Furthermore, in myelin oligodendrocyte glycoprotein (MOG)₃₅–₅₅-induced experimental autoimmune encephalomyelitis (EAE) mice, Morusin improved myelination-associated histological features and functional recovery, comparable to the benchmark compound Benztropine. Collectively, these findings identify Morusin as a promising natural compound with pro-myelinating activity across multiple experimental systems and highlight the potential of rationally guided natural compound screening for regenerative therapy in demyelinating diseases. Full article

Ischemic stroke is a leading cause of disability worldwide, marked by profound disruption of the neurovascular unit (NVU), a dynamic grouping of neurons, astrocytes, cerebral endothelial cells (CECs), microglia, pericytes, and oligodendrocytes. While acute stroke interventions such as tissue plasminogen activator and endovascular thrombectomy address reperfusion, they fail to engage the prolonged and cell-specific processes critical for recovery. Extracellular vesicles (EVs), membrane-bound carriers of proteins, lipids, and nucleic acids, have emerged as key modulators of intercellular communication within the NVU. This review synthesizes current evidence on NVU-derived EVs as both regulators and effectors of post-stroke pathology and repair. We highlight the phase-specific roles of EVs in modulating blood–brain barrier (BBB) integrity, thrombosis, angiogenesis, neurogenesis, oligodendrogenesis, synaptic plasticity, and neuroinflammation. This review places special emphasis on how EV cargo reflects the state of their parent cells and how EV-mediated crosstalk orchestrates coordinated neurorestorative responses. We further discuss the dual nature of EVs, their therapeutic potential for stroke, and the methodological challenges impeding clinical translation, including isolation standardization, cell-specific targeting, and regulatory barriers. Thus, adherence to minimal information for studies of extracellular vesicles (MISEV) guidelines is essential to ensure rigor, reproducibility, and transparency. When combined with temporal and cellular specificity, NVU-derived EVs may represent a biomimetic platform for promoting durable recovery in stroke patients. Full article

Glioblastoma (GB) is an extremely aggressive, highly invasive brain tumor of astrocytic or oligodendrocyte glial origin. This tumor often infiltrates adjacent healthy brain tissue and can migrate significant distances from the primary tumor site. Given the poor overall survival of GB patients and the limited efficacy of current local and systemic treatments, new therapeutic strategies are needed to improve outcomes, reduce side effects, and enhance patients’ quality of life. In recent years, the potential chemotherapeutic effects of natural molecules have been investigated, either as primary agents or in combination with established chemotherapies in various types of cancer. Melatonin (MLT, N-acetyl-5-methoxytryptamine) is an endogenous indolamine primarily secreted by the pineal gland. MLT appears to discriminate between normal and tumoral cellular contexts and to modulate appropriate actions, thereby acting as a “smart killer” against cancer cells; however, further studies are needed to clarify this apparently paradoxical behavior. This review aims to summarize recent findings on the potential regulatory role of MLT in the modulation of key intracellular pathways in GB, underlining its potential role as a complementary adjuvant to conventional therapies. The clinical advantage of MLT in GB patients has not been demonstrated in randomized controlled trials; therefore, multicenter studies with well-defined objectives, appropriate dosage schedules, and clear patient classification are needed. Full article