While N6-methyladenosine (m6A), the most abundant internal modification in eukaryotic mRNA, is linked to cell differentiation and tissue development, the biological significance of m6A modification in mammalian glial development remains unknown. Here, we identify a novel m6A reader, Prrc2a (Proline rich coiled-coil 2 A), which controls oligodendrocyte specification and myelination. Nestin-Cre-mediated knockout of Prrc2a induces significant hypomyelination, decreased lifespan, as well as locomotive and cognitive defects in a mouse model. Further analyses reveal that Prrc2a is involved in oligodendrocyte progenitor cells (OPCs) proliferation and oligodendrocyte fate determination. Accordingly, oligodendroglial-lineage specific deletion of Prrc2a causes a similar phenotype of Nestin-Cre-mediated deletion. Combining transcriptome-wide RNA-seq, m6A-RIP-seq and Prrc2a RIP-seq analysis, we find that Olig2 is a critical downstream target gene of Prrc2a in oligodendrocyte development. Furthermore, Prrc2a stabilizes Olig2 mRNA through binding to a consensus GGACU motif in the Olig2 CDS (coding sequence) in an m6A-dependent manner. Interestingly, we also find that the m6A demethylase, Fto, erases the m6A modification of Olig2 mRNA and promotes its degradation. Together, our results indicate that Prrc2a plays an important role in oligodendrocyte specification through functioning as a novel m6A reader. These findings suggest a new avenue for the development of therapeutic strategies for hypomyelination-related neurological diseases.

The present study examines the hypothesis that endogenous neural progenitor cells isolated from the neocortex of ischemic brain can differentiate into neurons or glial cells and contribute to neural regeneration. We performed middle cerebral artery occlusion to establish a model of cerebral ischemia/reperfusion injury in adult rats. Immunohistochemical staining of the cortex 1, 3, 7, 14 or 28 days after injury revealed that neural progenitor cells double-positive for nestin and sox-2 appeared in the injured cortex 1 and 3 days post-injury, and were also positive for glial fibrillary acidic protein. New neurons were labeled using bromodeoxyuridine and different stages of maturity were identified using doublecortin, microtubule-associated protein 2 and neuronal nuclei antigen immunohistochemistry. Immature new neurons coexpressing doublecortin and bromodeoxyuridine were observed in the cortex at 3 and 7 days post-injury, and semi-mature and mature new neurons double-positive for microtubule-associated protein 2 and bromodeoxyuridine were found at 14 days post-injury. A few mature new neurons coexpressing neuronal nuclei antigen and bromodeoxyuridine were observed in the injured cortex 28 days post-injury. Glial fibrillary acidic protein/bromodeoxyuridine double-positive astrocytes were also found in the injured cortex. Our findings suggest that neural progenitor cells are present in the damaged cortex of adult rats with cerebral ischemic brain injury, and that they differentiate into astrocytes and immature neurons, but most neurons fail to reach the mature stage.

Astrocytes can be involved in motor neuron toxicity in amyotrophic lateral sclerosis (ALS) induced by noncell autonomous effects, and inflammatory cytokines may play the main role in mediating this process. However, the etiology of aberrant cytokine secretion is unclear. The present study assessed possible involvement of the mTOR-autophagy pathway in aberrant cytokine secretion by ALS patient iPSC-derived astrocytes. Method and Results. PBMCs from sporadic ALS patients and control subjects were reprogrammed into iPSCs, which were then differentiated into astrocytes and/or motor neurons. Comparison with control astrocytes indicated that conditioned medium of ALS astrocytes reduced the viability of the control motor neurons (p < 0.05) assessed using the MTT assay. The results of ELISA showed that the concentrations of TNFα, IL1β, and IL6 in cell culture medium of ALS astrocytes were increased (p < 0.05). ALS astrocytes had higher p62 and mTOR levels and lower LC3BII/LC3BI ratio and ULK1 and p-Beclin-1 (Ser15) levels (p < 0.05), indicating defective autophagy. Exogenous inhibition of the mTOR-autophagy pathway, but not the activation of the pathway in control subject astrocytes, increased the levels of p62 and mTOR and concentration of IL-1β, TNF-α, and IL-6 in cell culture medium and decreased the LC3BII/LC3BI ratio and levels of ULK1 and p-Beclin-1 (Ser15), and these changes were comparable to those in ALS astrocytes. After 48 h of rapamycin (autophagy activator) and 3-methyladenine (autophagy inhibitor) treatments, the exogenous activation of the mTOR-autophagy pathway, but not inhibition of the pathway, in ALS astrocytes significantly reduced the concentrations of TNFα, IL1β, and IL6 in cell culture medium and reduced the levels of p62, while increasing the levels of LC3B-II/LC3B-I, ULK1, and p-Beclin-1 (Ser15), and these changes were comparable to those in control subject astrocytes.

Apolipoprotein E (APOE) gene encodes three protein isoforms (APOEε-22/ε-33/ε-44), which governs the transportation and metabolism of lipoproteins differently. While abnormalities in lipid and lipoprotein metabolism have been identified as risk factors for type 2 diabetes mellitus (T2DM). APOE gene polymorphisms might be correlated with increased risk of T2DM. Therefore, we presented an iPSC line harboring an APOE-ε3/ε3 alleles, a male donor suffering from T2DM combined with Hypertension. The derived iPSCs showed pluripotency, the capacity to differentiate into three germ layers, and normal karyotypes. Collectively, the present study provides a useful resource to reveal the associated mechanism of APOE isoform and T2DM.

Induced pluripotent stem cells (iPSCs) can be used to generate different types of somatic cells in vitro, including neuronal cells. Here, a human iPSC line was generated from the peripheral blood mononuclear cells of a healthy 39-year-old individual. The resulting iPSCs were integration-free, maintained the normal karyotype, expressed pluripotency stem cell markers, and were demonstrated to be capable of differentiating into cells representative of the three embryonic germ layers. Furthermore, we showed that this iPSC line could be differentiated into neural stem cells. Taken together, this generated iPSC line could be useful to test multiple differentiation protocols, and also serve as a control for investigating drug development and disease mechanisms.

Apolipoprotein E ε4 allele (APOE4) is a minor allele of the APOE gene associated with a higher risk for Alzheimer's Disease (AD) and Vascular Dementia (VD). While lipid deposition and chronic inflammation in glia are the commonalities between atherosclerosis, VD, and AD. Hence, we presented an iPSC line of an AD male donor suffering from Cerebrovascular Atherosclerosis with APOE-ε4/ε4 alleles background. Furthermore, we differentiated the iPSCs into astrocyte to explore pathogenesis in APOE4 related dementia. The characterized iPSC line expressed typical pluripotency markers and showed differentiation potential and normal karyotype.

The ε4 allele of the Apolipoprotein E gene (APOE4) continues to be the strongest genetic risk factor associated with sporadic Alzheimer's disease since its discovery compared to the most common ε3 allele. Nevertheless, there is a lack of APOE4-mutant human neuronal models in vitroor in vivo. Hence, we presented an iPSC line of an APOE-ε4/ε4 alleles carrier, a male donor suffering from Alzheimer's disease combined with cerebral infarction. The established iPSC line showed standard characteristics of pluripotency. Collectively, the present study provides a useful resource to reveal the phenotype and explore the mechanism of APOE4 related Alzheimer's disease.

Apolipoprotein E (ApoE) is a lipid-binding protein with ε2, ε3, and ε4 allelic variants in human. The ε4 isoform (ApoE4) is the strongest genetic risk factor for the late-onset form of Alzheimer's disease (AD), and is also associated with multiple neurological disorders, multiple sclerosis, and cerebrovascular disease. Here, induced pluripotent stem cells were derived from the peripheral blood mononuclear cells of a 70-year-old male donor with APOE-ε4/ε4 alleles background to explore pathogenesis and screen potential treatment methods in neurodegenerative diseases. In the newly-developed induced pluripotent stem cell line, the pluripotent markers were well expressed. In addition, the generated cells displayed a normal karyotype and have differentiation potential.

In this study, skin biopsy was collected from a healthy 48-year old male donor with informed consent, and the fibroblasts were isolated from the dermal explant cultures. Here, a human induced pluripotent stem cell (iPSC) line was derived from the fibroblasts using the reprogramming four Yamanaka factors (Oct3/4, Sox2, Klf4, c-Myc). The generated iPSCs were integration-free, displayed the normal karyotype, expressed pluripotency markers and demonstrated trilineage differentiation potential in vitro. This iPSC model will be useful for investigating physiological processes, drug validation as well as a control in pathological mechanistic studies.

Potocki-Lupski syndrome (PTLS; MIM 610883) is a neurodevelopmental disorder associated with a 3.7 Mb copy number variant (CNV) duplication, locating in chromosome 17p11.2. (Soler-Alfonso et al., 2011). Here, a human induced pluripotent stem cell (iPSC) line was derived from the peripheral blood mononuclear cells of a 5-year-old child suffering Potocki-Lupski syndrome. The generated iPSCs were integration-free, had the 17p11.2 3.7 Mb CNV duplication with no additional genomic alterations, a stable karyotype, expressed pluripotency stem cell markers and could differentiate towards the three germ layers in vitro. Patient's derived iPSCs are a valuable resource for in vitro modeling of 17p11.2 microduplication induced Potocki-Lupski syndrome.