Myelin oligodendrocyte glycoprotein-associated transverse myelitis after SARS-CoV-2 infection: A case report.

BACKGROUND: Cases of myelin oligodendrocyte glycoprotein (MOG) antibody-related disease have a history of coronavirus disease 2019 infection or its vaccination before disease onset. Severe acute respiratory syndrome virus 2 (SARS-CoV-2) infection has been considered to be a trigger of central nervous system autoimmune diseases. CASE SUMMARY: Here we report a 20-year male with MOG-associated transverse myelitis after a SARS-CoV-2 infection. The patient received a near-complete recovery after standard immunological treatments. CONCLUSION: Attention should be paid to the evaluation of typical or atypical neurological symptoms that may be triggered by SARS-CoV-2 infection.

Aggressive Course of Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease (MOGAD): An Illustration of Two Cases and Review of Literature.

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is a central nervous system demyelinating disease that has become a major source of morbidity among children and adults. In the first case, we present an 18-year-old Hispanic female with a recently resolved upper respiratory infection who presented with fever, headache, progressive quadriparesis, urinary retention, and encephalopathy. The hospital course involved autonomic dysfunction and prolonged intubation requiring tracheostomy and gastrostomy. Cerebrospinal fluid (CSF) showed pleocytosis and a positive MOG titer (1:40). Magnetic resonance imaging (MRI) showed longitudinally extensive cervicothoracic T2 hyperintensity and brain multifocal T2 hyperintensities. After high-dose intravenous methylprednisolone (IVMP) and intravenous immunoglobulin (IVIG), she had full neurological recovery by the last follow-up. The second case is of a 22-year-old Hispanic male who presented with progressive lower extremity paresthesia and weakness over six weeks. CSF demonstrated pleocytosis, elevated protein, oligoclonal bands, and MOG antibody. MRI revealed multiple subcortical T2-hyperintense lesions and enhancing midcervical and lower thoracic lesions. Treatment with IVMP led to minor improvement with discharge on steroid taper and azathioprine. The patient's disease progressed with a fluctuating course requiring two readmissions with upper extremity weakness, right optic neuritis, and urinary sphincteric dysfunction with neuroradiologic worsening. Treatment throughout multiple admissions included intravenous steroids, IVIG, plasmapheresis, mycophenolate mofetil, and rituximab with minimal improvement, symptom recurrence, and progression of multifocal lesions. The patient died four months after the symptom onset. These cases had markedly different treatment responses despite similar baseline characteristics. The difference in morbidity and disability burden highlights the importance of further investigation of this condition through clinical trials.

Diverse functions of DEAD-box proteins in oligodendrocyte development, differentiation, and homeostasis.

Oligodendrocytes, a type of glial cell in the central nervous system, have a critical role in the formation of myelin around axons, facilitating saltatory conduction, and maintaining the integrity of nerve axons. The dysregulation of oligodendrocyte differentiation and homeostasis have been implicated in a wide range of neurological diseases, including dysmyelinating disorders (e.g., Pelizaeus-Merzbacher disease), demyelinating diseases (e.g., multiple sclerosis), Alzheimer's disease, and psychiatric disorders. Therefore, unraveling the mechanisms of oligodendrocyte development, differentiation, and homeostasis is essential for understanding the pathogenesis of these diseases and the development of therapeutic interventions. Numerous studies have identified and analyzed the functions of transcription factors, RNA metabolic factors, translation control factors, and intracellular and extracellular signals involved in the series of processes from oligodendrocyte fate determination to terminal differentiation. DEAD-box proteins, multifunctional RNA helicases that regulate various intracellular processes, including transcription, RNA processing, and translation, are increasingly recognized for their diverse roles in various aspects of oligodendrocyte development, differentiation, and maintenance of homeostasis. This review introduces the latest insights into the regulatory networks of oligodendrocyte biology mediated by DEAD-box proteins.

Quality of life in patients with myelin oligodendrocyte glycoprotein antibody associated disease compared to patients with AQP4-IgG positive neuromyelitis optica spectrum disorders: A Korean multicenter study.

BACKGROUND: Little is known about the quality of life (QOL) of patients with myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD). We compared QOL and associated factors in patients with MOGAD and aquaporin4 IgG (AQP4-IgG) positive neuromyelitis optica spectrum disorder (NMOSD). METHODS: This multicenter questionnaire study compared the QOL of 41 patients with MOGAD and 78 with AQP4-IgG positive NMOSD. Patients who were positive for AQP4-IgG or MOG antibodies were included. WHO Quality of Life Scale Brief Version was used to assess QOL in physical, psychological, social, and environmental domains. QOL, sleep quality, pain, fatigue, and depression were compared between the two groups. The factors associated with QOL in each group and the entire cohort were analyzed. RESULTS: The proportion of patients with poor QOL was not significantly different between MOGAD (51.22 %) and AQP4-IgG positive NMOSD (58.97 %, p = 0.054). In the MOGAD group, the pain score (ß=-1.032, p = 0.001) and depression score (ß=-0.694, p = 0.007) were negatively associated with physical and psychological QOL, respectively. Sleep quality was negatively associated with physical (ß=-1.506, p = 0.034) and psychological (ß =-2.064, p = 0.033) QOL. When the entire cohort was analyzed, a positive MOG antibody was independently associated with worse psychological QOL (ß=-8.998, p = 0.013) compared to positive AQP4-Ab after adjustment for sleep quality, depression, fatigue, and pain. CONCLUSIONS: The overall QOL of the patients of MOGAD was comparable to that of AQP4-IgG positive NMOSD. Patients with MOGAD were experiencing sleep disorder, fatigue, and depression at similar degrees to those of patients with AQP4-IgG positive NMOSD. Further consideration of sleep quality and psychological QOL is required to improve QOL in patients with MOGAD.

Myelination potential and injury susceptibility of grey versus white matter human oligodendrocytes.

Increasing evidence indicates heterogeneity in functional and molecular properties of oligodendrocyte lineage cells both during development and under pathologic conditions. In multiple sclerosis, remyelination of grey matter lesions exceeds that in white matter. Here we used cells derived from grey matter versus white matter regions of surgically resected human brain tissue samples, to compare the capacities of human A2B5-positive progenitor cells and mature oligodendrocytes to ensheath synthetic nanofibers, and relate differences to the molecular profiles of these cells. For both cell types, the percentage of ensheathing cells was greater for grey matter versus white matter cells. For both grey matter and white matter samples, the percentage of cells ensheathing nanofibers was greater for A2B5-positive cells versus mature oligodendrocytes. Grey matter A2B5-positive cells were more susceptible than white matter A2B5-positive cells to injury induced by metabolic insults. Bulk RNA sequencing indicated that separation by cell type (A2B5-positive vs mature oligodendrocytes) is more significant than by region but segregation for each cell type by region is apparent. Molecular features of grey matter versus white matter derived A2B5-positive and mature oligodendrocytes were lower expression of mature oligodendrocyte genes and increased expression of early oligodendrocyte lineage genes. Genes and pathways with increased expression in grey matter derived cells with relevance for myelination included those related to responses to external environment, cell-cell communication, cell migration, and cell adhesion. Immune and cell death related genes were up-regulated in grey matter derived cells. We observed a significant number of up-regulated genes shared between the stress/injury and myelination processes, providing a basis for these features. In contrast to oligodendrocyte lineage cells, no functional or molecular heterogeneity was detected in microglia maintained in vitro, likely reflecting the plasticity of these cells ex vivo. The combined functional and molecular data indicate that grey matter human oligodendrocytes have increased intrinsic capacity to myelinate but also increased injury susceptibility, in part reflecting their being at a stage earlier in the oligodendrocyte lineage.

The role of oligodendrocyte progenitor cells in the spatiotemporal vascularization of the human and mouse neocortex.

Brain vasculature formation begins with vessel invasion from the perineural vascular plexus, which expands through vessel sprouting and growth. Recent studies have indicated the existence of oligodendrocyte-vascular crosstalk during development. However, the relationship between oligodendrocyte progenitor cells (OPCs) and the ordered spatiotemporal vascularization of the neocortex has not been elucidated. Our findings suggest that OPCs play a complex role in the vessel density of the embryonic and postnatal neocortex. Analyses of normal human and mouse embryonic cerebral cortex show that vascularization and OPC distribution are tightly controlled in a spatially and temporally restricted manner, exhibiting a positive correlation. Loss of OPCs at both embryonic and postnatal stages led to a reduction in vascular density, suggesting that OPC populations play a role in vascular density. Nonetheless, dynamic observation on cultured brain slices and staining of tissue sections indicate that OPC migration is unassociated with the proximity to blood vessels, primarily occurring along radial glial cell processes. Additionally, in vitro experiments demonstrate that OPC secretions promote vascular endothelial cell (VEC) growth. Together, these observations suggest that vessel density is influenced by OPC secretions.

Employment, work hours, and wages in adults with myelin oligodendrocyte glycoprotein antibody disease: An international cohort study.

OBJECTIVES: The objectives were to understand the employment impacts of myelin oligodendrocyte glycoprotein-associated antibody disease (MOGAD) on adults in an international cohort by determining lost employment, work hours, and wages. BACKGROUND: Clinically, MOGAD can be associated with significant disability; however, its socioeconomic consequences for adults are barely reported. METHODS: Participants of potential working age (18-70 years old) with neurologist-diagnosed MOGAD were recruited from clinical sites in 13 countries, April 2022 to August 2023. Each participant completed a one-time survey. Regression models assessed associations with post-MOGAD (1) unemployment and (2) work hours. RESULTS: A total of 117 participants (66.7% female), mean age 39.7 years, median disease duration 3 years (25th, 75th percentile: 1, 7) were analyzed. Employment post-MOGAD reduced from 74 (63.2%) to 57 (48.7%) participants. Participants employed pre-diagnosis reduced their work hours, on average, from 31.6 hours/week to 19.5 hours/week post-diagnosis. Residence in a high-income country was statistically significantly associated with post-diagnosis employment and higher weekly work hours. Depressed mood was associated with unemployment. MOGAD-related pain and history of myelitis were independently associated with lost work hours. CONCLUSION: MOGAD can have significant impacts on adult employment, particularly in non-high-income countries. Depressed mood and pain are potentially modifiable factors related to socioeconomic status in MOGAD.

Efficacy of tocilizumab in highly relapsing MOGAD with an inadequate response to intravenous immunoglobulin therapy: A case series.

BACKGROUND: Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is an inflammatory disease affecting the central nervous system that may require long-term immunotherapy in relapsing cases. While immunotherapies utilized in neuromyelitis optica spectrum disorder have shown varying efficacy in MOGAD, intravenous immunoglobulin G (IVIG) recently emerged as a promising treatment. Tocilizumab, a monoclonal antibody that targets the interleukin-6 (IL-6) receptor, has been reported to be effective in refractory MOGAD in several case studies, where tocilizumab was introduced primarily due to rituximab failure. METHODS: This retrospective study was conducted in a single center and focused on MOGAD patients receiving tocilizumab therapy, who have shown limited response to various immunotherapies, including intravenous immunoglobulin G (IVIG) maintenance. RESULTS: This study included four patients, three adults, and one child. They experienced a median of 9 attacks (range 6-9) throughout their disease course despite at least two immunotherapies. All patients transitioned to tocilizumab after experiencing a median of two relapses (range 1-3) while on IVIG maintenance for a median of 21.9 months (range 21.3-49.6 months). Following the monthly tocilizumab administration at a dose of 8g/kg, all patients remained relapse-free with a median follow-up duration of 25.0 months (range 9.8-51.3 months) without reported adverse events. CONCLUSION: Targeting the IL-6 pathway appears to offer therapeutic benefits in highly relapsing MOGAD patients who poorly respond to IVIG maintenance therapy.

Radiological features in pediatric myelin oligodendrocyte glycoprotein antibody-associated disease-diagnostic criteria and lesion dynamics.

The spectrum of acquired pediatric demyelinating syndromes has been expanding over the past few years, to include myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD), as a distinct neuroimmune entity, in addition to pediatric-onset multiple sclerosis (POMS) and aquaporin 4-IgG-seropositive neuromyelitis optica spectrum disorder (AQP4+NMOSD). The 2023 MOGAD diagnostic criteria require supporting clinical or magnetic resonance imaging (MRI) features in patients with low positive myelin oligodendrocyte glycoprotein IgG titers or when the titers are not available, highlighting the diagnostic role of imaging in MOGAD. In this review, we summarize the key diagnostic features in MOGAD, in comparison to POMS and AQP4+NMOSD. We describe the lesion dynamics both during attack and over time. Finally, we propose a guideline on timing of imaging in clinical practice.

Impact of autoantibodies against myelin oligodendrocyte glycoprotein in paediatric acquired demyelinating disease: Intellectual functioning and academic performance.

Paediatric acquired demyelinating syndromes (pADS) attack white matter pathways in the brain during an important period of development. Affected children can experience poor functional outcomes, including deficits in specific cognitive domains. Understanding risk factors for poor outcome will guide clinical management of these children. One clinical phenotype which may differentially impact cognitive outcomes is the presence of autoantibodies to myelin oligodendrocyte glycoprotein (MOG). Preliminary research has suggested that cognitive difficulties exist in paediatric patients who test positive for MOG antibodies or MOGAD (Myelin Oligodendrocyte Glycoprotein Associated Disease) however, they experience a less severe profile compared to seronegative counterparts. The current study assesses children diagnosed with pADS who tested positive or negative for MOG-ab using standardised assessments of both intellectual functioning and academic ability. The results show that a subset of MOGAD patients experience clinically significant sequalae in intellectual functioning and academic ability. The neuropsychological profile also differed between children with and without MOG-ab positivity, with seronegative patients more likely to show a clinically relevant difficulties at the individual patient level. Whilst no differences existed at the group-level; the current study demonstrates the relative additional risk of intellectual/academic difficulty associated with MOG-ab seronegativity. This research further supports the growing perspective that MOG-positivity confers a more favourable neuropsychological outlook than is the case for their seronegative counterparts. This broadening consensus offers reassurance for clinicians, families, and patients.

Lateral/caudal ganglionic eminence makes limited contribution to cortical oligodendrocytes.

The emergence of myelinating oligodendrocytes represents a pivotal developmental milestone in vertebrates, given their capacity to ensheath axons and facilitate the swift conduction of action potentials. It is widely accepted that cortical oligodendrocyte progenitor cells (OPCs) arise from medial ganglionic eminence (MGE), lateral/caudal ganglionic eminence (LGE/CGE), and cortical radial glial cells (RGCs). Here, we used two different fate mapping strategies to challenge the established notion that the LGE generates cortical OPCs. Furthermore, we used a Cre/loxP-dependent exclusion strategy to reveal that the LGE/CGE does not give rise to cortical OPCs. Additionally, we showed that specifically eliminating MGE-derived OPCs leads to a significant reduction of cortical OPCs. Together, our findings indicate that the LGE does not generate cortical OPCs, contrary to previous beliefs. These findings provide a new view of the developmental origins of cortical OPCs and a valuable foundation for future research on both normal development and oligodendrocyte-related disease.

Case report: The histopathological analyses of two myelin oligodendrocyte glycoprotein antibody-associated diseases with a distinctive linear radiating gadolinium enhancement on MRI.

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) has highly heterogeneous clinical presentations, in which encephalitis is an important phenotype. Moreover, MOGAD has been reported to exhibit diverse imaging findings. However, there have been no previous reports of cases with perivascular radial gadolinium enhancement in periventricular regions, commonly reported in autoimmune glial fibrillary acidic protein (GFAP) astrocytopathy. In this paper, we present two cases of MOGAD with this MRI feature, both of which underwent brain biopsy for the lesions. Brain biopsies revealed perivenous demyelination and inflammation consistent with acute disseminated encephalomyelitis (ADEM), with pronounced axonal damage in Case 1 and minimal axonal involvement in Case 2. Case 1 exhibited more severe cerebral atrophy than Case 2, correlating with the extent of axonal damage. Through these cases, we highlight the heterogeneity of radiological manifestations of MOGAD, expanding the spectrum beyond previously defined MRI patterns. Furthermore, histopathological analysis revealed distinct axonal involvement as a potential prognostic marker of brain atrophy. These observations emphasize the importance of considering MOGAD in the differential diagnosis, even in cases with atypical imaging findings, and highlight the significance of brain biopsy in guiding both diagnosis and prognosis.

Autophagy in Oligodendrocyte Lineage Cells Controls Oligodendrocyte Numbers and Myelin Integrity in an Age-dependent Manner.

Oligodendrocyte lineage cells, including oligodendrocyte precursor cells (OPCs) and oligodendrocytes (OLs), are essential in establishing and maintaining brain circuits. Autophagy is a conserved process that keeps the quality of organelles and proteostasis. The role of autophagy in oligodendrocyte lineage cells remains unclear. The present study shows that autophagy is required to maintain the number of OPCs/OLs and myelin integrity during brain aging. Inactivation of autophagy in oligodendrocyte lineage cells increases the number of OPCs/OLs in the developing brain while exaggerating the loss of OPCs/OLs with brain aging. Inactivation of autophagy in oligodendrocyte lineage cells impairs the turnover of myelin basic protein (MBP). It causes MBP to accumulate in the cytoplasm as multimeric aggregates and fails to be incorporated into integral myelin, which is associated with attenuated endocytic recycling. Inactivation of autophagy in oligodendrocyte lineage cells impairs myelin integrity and causes demyelination. Thus, this study shows autophagy is required to maintain myelin quality during aging by controlling the turnover of myelin components.

What's new in NMOSD and MOGAD?

In this mini-review, we focus on novelties in the field of neuromyelitis optica spectrum disorders (NMOSD) and myelin oligodendrocyte glycoprotein antibody associated disease (MOGAD). We first describe the proposed criteria for MOGAD and evaluate their impact and potential limitations, with a highlight on the subgroups of patients tested MOG-antibody positive only in the cerebrospinal fluid. We then propose a brief state of the art on the current knowledge on the so-call "double seronegative" NMOSD group, regarding nosology, clinical, biological and imaging features and the unmet need in this field. The last part is dedicating to the present and future of acute treatment in NMSOD and MOGAD.

Neuroprotective Effect of Flavonoid Agathisflavone in the Ex Vivo Cerebellar Slice Neonatal Ischemia.

Agathisflavone is a flavonoid that exhibits anti-inflammatory and anti-oxidative properties. Here, we investigated the neuroprotective effects of agathisflavone on central nervous system (CNS) neurons and glia in the cerebellar slice ex vivo model of neonatal ischemia. Cerebellar slices from neonatal mice, in which glial fibrillary acidic protein (GFAP) and SOX10 drive expression of enhanced green fluorescent protein (EGFP), were used to identify astrocytes and oligodendrocytes, respectively. Agathisflavone (10 µM) was administered preventively for 60 min before inducing ischemia by oxygen and glucose deprivation (OGD) for 60 min and compared to controls maintained in normal oxygen and glucose (OGN). The density of SOX-10+ oligodendrocyte lineage cells and NG2 immunopositive oligodendrocyte progenitor cells (OPCs) were not altered in OGD, but it resulted in significant oligodendroglial cell atrophy marked by the retraction of their processes, and this was prevented by agathisflavone. OGD caused marked axonal demyelination, determined by myelin basic protein (MBP) and neurofilament (NF70) immunofluorescence, and this was blocked by agathisflavone preventative treatment. OGD also resulted in astrocyte reactivity, exhibited by increased GFAP-EGFP fluorescence and decreased expression of glutamate synthetase (GS), and this was prevented by agathisflavone pretreatment. In addition, agathisflavone protected Purkinje neurons from ischemic damage, assessed by calbindin (CB) immunofluorescence. The results demonstrate that agathisflavone protects neuronal and myelin integrity in ischemia, which is associated with the modulation of glial responses in the face of ischemic damage.

Rapid differentiation of MOGAD and MS after a single optic neuritis.

BACKGROUND: Optic neuritis (ON) is a common manifestation of multiple sclerosis (MS) and myelin-oligodendrocyte-glycoprotein IgG-associated disease (MOGAD). This study evaluated the applicability of optical coherence tomography (OCT) for differentiating between both diseases in two independent cohorts. METHODS: One hundred sixty two patients from seven sites underwent standard OCT and high-contrast visual acuity (HCVA) testing at least 6 months after first ON. Of these, 100 patients (32 MOGAD, 68 MS) comprised the primary investigational cohort, while 62 patients (31 MOGAD, 31 MS) formed a validation cohort. A composite score distinguishing between MOGAD and MS was developed using multivariate logistic regression. RESULTS: Bilateral simultaneous ON occurred more frequently in MOGAD compared to MS (46.9 vs. 11.8%, p < 0.001). OCT revealed more peripapillary retinal nerve fiber layer (pRNFL) atrophy in all segments in MOGAD compared to predominantly temporal pRNFL atrophy in MS (p < 0.001). HCVA was better preserved in MS (p = 0.007). pRNFL thickness in all except for temporal segments was suitable for differentiating MOGAD and MS. Simultaneous bilateral ON and critical atrophy in nasal (< 58.5 µm) and temporal superior (< 105.5 µm) segments were included into the composite score as three independent predictors for MOGAD. The composite score distinguished MOGAD from MS with 75% sensitivity and 90% specificity in the investigational cohort, and 68% sensitivity and 87% specificity in the validation cohort. CONCLUSION: Following a single ON-episode, MOGAD exhibits more pronounced global pRNFL atrophy and lower visual acuity after ON compared to MS. The introduced OCT-based composite score enabled differentiation between the two entities across both cohorts.

Myelin oligodendrocyte glycoprotein antibody-associated cerebral cortical encephalitis with super-refractory status epilepticus.

BACKGROUND: Seizures are commonly reported in patients with myelin oligodendrocyte glycoprotein antibody-associated cerebral cortical encephalitis (MOG-CCE). However, seizure management during the acute phase has not been established. CASE REPORT: A 9-year-old previously healthy boy presented with fever persisting for approximately 6 days, along with headache and altered consciousness. Plain T2-weighted and fluid-attenuated inversion recovery imaging showed swelling and abnormal hyperintense lesions in the bilateral frontal, parietal, temporal, and insular cortices with left hemisphere predominance. Consciousness disturbance persisted, and focal myoclonic seizures clustered hourly. Seizures were arrested by titrating the thiopental dose but recurred with dose reduction, and the patient exhibited super refractory status epilepticus. Adverse effects due to long-term use of thiopental became apparent. Hence, continuous infusion of ketamine and intrathecal dexamethasone therapy (IT-DEX) was started. After administration of ketamine and IT-DEX, his seizure was arrested promptly. The cerebrospinal fluid and serum at the time of transfer were clear positive for ani-MOG antibody; therefore, the patient was diagnosed with MOG-CCE. The patient received three courses of intravenous methylprednisolone pulse therapy, followed by oral prednisolone gradually tapered over 6 months. He did not experience any relapse for 6 months. CONCLUSION: In MOG-CCE, some cases may present with super-refractory status epilepticus (SRSE) in the acute phase and be refractory to anti-seizure medication, analogous to febrile infection-related epilepsy syndrome. IT-DEX and continuous infusion ketamine are useful for seizure control in MOG-CCE.

Prognostic significance of oligodendrocyte transcription factor 2 expression in glioma patients: A systematic review and meta-analysis.

BACKGROUND: Gliomas are the most common primary central nervous system neoplasm. Despite recent advances in the diagnosis and treatment of gliomas, patient prognosis remains dismal. Therefore, it is imperative to identify novel diagnostic biomarkers and therapeutic targets of glioma to effectively improve treatment outcomes. AIM: To investigate the association between oligodendrocyte transcription factor 2 (Olig2) expression and the outcomes of glioma patients. METHODS: The PubMed, Embase, Cochrane Library, and China National Knowledge Infrastructure databases were searched for studies (published up to October 2023) that investigated the relationship between Olig2 expression and prognosis of glioma patients. The quality of the studies was assessed using the Newcastle Ottawa Scale. Data analyses were performed using Stata Version 12.0 software. RESULTS: A total of 1205 glioma patients from six studies were included in the meta-analysis. High Olig2 expression was associated with better outcomes in glioma patients [hazard ratio (HR): 0.81; 95% (confidence interval) CI: 0.51-1.27; P = 0.000]. Furthermore, the results of subgroup meta-analysis showed that high expression of Olig2 was associated with poor overall survival in European patients (HR: 1.34; 95%CI: 0.79-2.27) and better prognosis in Asian patients (HR: 0.43; 95%CI: 0.22-0.84). The sensitivity analysis showed that no single study had a significant effect on pooled HR, and there was also no indication of publication bias according to the Egger's and Begger's P value test or funnel plot test. CONCLUSION: High Olig2 expression may have a positive impact on the prognosis of glioma patients, and should be investigated further as a prognostic biomarker and therapeutic target for glioma.

From BBB to PPP: Bioenergetic requirements and challenges for oligodendrocytes in health and disease.

Mature myelinating oligodendrocytes, the cells that produce the myelin sheath that insulates axons in the central nervous system, have distinct energetic and metabolic requirements compared to neurons. Neurons require substantial energy to execute action potentials, while the energy needs of oligodendrocytes are directed toward building the lipid-rich components of myelin and supporting neuronal metabolism by transferring glycolytic products to axons as additional fuel. The utilization of energy metabolites in the brain parenchyma is tightly regulated to meet the needs of different cell types. Disruption of the supply of metabolites can lead to stress and oligodendrocyte injury, contributing to various neurological disorders, including some demyelinating diseases. Understanding the physiological properties, structures, and mechanisms involved in oligodendrocyte energy metabolism, as well as the relationship between oligodendrocytes and neighboring cells, is crucial to investigate the underlying pathophysiology caused by metabolic impairment in these disorders. In this review, we describe the particular physiological properties of oligodendrocyte energy metabolism and the response of oligodendrocytes to metabolic stress. We delineate the relationship between oligodendrocytes and other cells in the context of the neurovascular unit, and the regulation of metabolite supply according to energetic needs. We focus on the specific bioenergetic requirements of oligodendrocytes and address the disruption of metabolic energy in demyelinating diseases. We encourage further studies to increase understanding of the significance of metabolic stress on oligodendrocyte injury, to support the development of novel therapeutic approaches for the treatment of demyelinating diseases.

Polyautoimmunity and multiple autoimmune syndrome in patients with neuromyelitis optica spectrum disorder.

BACKGROUND: The coexistence of neuromyelitis optica spectrum disorders (NMOSD) with other autoimmune diseases (AID) has been increasingly reported. The prevalence and significance of this association are not fully understood. OBJECTIVES: This study aimed to compare the clinical and laboratory characteristics in NMOSD patients with and without AID. METHODS: Retrospective cross-sectional observational study was conducted involving adults meeting NMOSD criteria followed in a neuroimmunology clinic at a tertiary center. Descriptive analysis of clinical/paraclinical/treatment/outcome data collected from the medical records was compared between NMOSD patients with AID (polyautoimmunity) and those without AID. RESULTS: From a cohort of 46 NMOSD patients, 16 (34.8 %) patients, mostly women around 40 years of age, presented with polyautoimmunity: 10 anti-AQP4 positive, 4 anti-MOG positive, and 2 seronegative. Five different organ -specific AID, and six systemic AID were identified in the polyautoimmunity patients group, in addition to 6 cases of multiple autoimmune syndrome. The AID manifestation preceded NMOSD in 10 (62.5 %) patients, with a median interval of 7 years. The NMOSD with polyautoimmunity and NMOSD without AID groups had similar initial clinical manifestations with optic neuritis and/or myelitis being most frequent. Inflammatory CSF, namely elevated proteins, was more common in the polyautoimmunity group (13.0 % in NMOSD vs. 31.3 % in NMOSD+AID, p = 0.003). After a 10±6 years follow-up period, more patients with polyautoimmunity had a relapsing disease (75.0 % in NMOSD vs. 46.7 % in NMOSD+AID, p = 0.012) but no difference in the functional outcome evaluated by the EDSS score was identified. CONCLUSIONS: Polyautoimmunity was common in AQP4 positive NMOSD patients leading to a significantly higher risk of disease recorrence. The presence of polyautoimmunity and multiple autoimmune syndrome in NMOSD patients suggests the existence of common susceptibility factors or pathophysiological mechanisms, emphasizing the importance of a multidisciplinary approach to those patients.