Children with SOX2 deficiency develop ocular disorders and extra-ocular CNS anomalies. Animal data show that SOX2 is essential for retinal and neural stem cell development. In the CNS parenchyma, SOX2 is primarily expressed in astroglial and oligodendroglial cells. Here, we report a crucial role of astroglial SOX2 in postnatal brain development. Astroglial Sox2-deficient mice develop hyperactivity in locomotion and increased neuronal excitability in the corticostriatal circuit. Sox2 deficiency inhibits postnatal astrocyte maturation molecularly, morphologically, and electrophysiologically without affecting astroglia proliferation. Mechanistically, SOX2 directly binds to a cohort of astrocytic signature and functional genes, the expression of which is significantly reduced in Sox2-deficient CNS and astrocytes. Consistently, Sox2 deficiency remarkably reduces glutamate transporter expression and compromised astrocyte function of glutamate uptake. Our study provides insights into the cellular mechanisms underlying brain defects in children with SOX2 mutations and suggests a link of astrocyte SOX2 with extra-ocular abnormalities in SOX2-mutant subjects.

Background: Parkinson's disease (PD) is a common neurodegenerative disorder that affects 1%-2% of the population over 60 years old. Immune response dysfunction in the brain contributes to the occurrence and development of PD. This study aimed to uncover the potential diagnostic genes for PD and characterize the immune cell infiltrates. Methods: We downloaded the microarray data of patients with PD samples from the Gene Expression Omnibus (GEO) database. Weighted Gene Co-Expression Network Analysis (WGCNA) was used to identify the modules linked to PD in the GSE20163 dataset. Meanwhile, differentially expressed genes (DEGs) between the healthy control samples and PD samples were also identified. Then the PD-related genes were integrated based on the genes in the key module and DEGs. Functional enrichment analysis was used to explore the molecular mechanisms of these PD-related genes. Protein-protein interaction (PPI) network and least absolute shrinkage and selection operator (LASSO) analysis were used to further screen candidate genes for PD. Gene set enrichment analysis (GSEA) was applied to explore the biological functions of these candidate genes. The infiltration of immune cells was detected by single-sample gene set enrichment analysis (ssGSEA) algorithm in the GSE20163 dataset, and Pearson analysis was used to investigate the correlation of candidate genes with immune cells and immune checkpoint proteins. The expression of candidate genes in clinical samples was verified by qPCR. Results: Altogether, we found a unique gene module related to PD, where 109 DEGs were identified in the GSE20163 dataset. Following these results, we screened 68 genes associated with PD. Gene Expression Omnibus (GEO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses suggested that these genes were markedly enriched in the pathway of synthesis and transport of neurons. Three candidate genes (SLC18A2, CALB1, and SYNGR3) were further identified in PD patients through PPI network and LASSO analysis. The receiver operating characteristic (ROC) curve indicated that the three candidate genes had a good performance in distinguishing the PD samples from healthy control samples. The proportions of the aDC, DC, NK CD56dim cells, and follicular helper T cells (TFH) were obviously different between the healthy control and PD samples. Moreover, CTLA4, LAG3, CEACAM1, and CD27 were highly expressed in the PD group. GSEA analysis for candidate genes revealed that they were all closely related to the neurogenic disease. Additionally, the three candidate genes were all strongly correlated with the above immune cells and immune checkpoint proteins. The qPCR results validated the expression differences of SLC18A2 and SYNGR3 in the clinical PD and control samples. Conclusion: The three candidate genes may be a useful tool for diagnosing PD patients. These findings provide a reference for exploring new therapeutic targets and strategies for PD treatment.

S100A8/A9, a heterodimer complex composed of calcium-binding proteins S100A8 and S100A9, is significantly increased in the serum of multiple sclerosis (MS) patients. Relevant reports have revealed that MS pathology is commonly associated with the activation of microglial cells and the damage of oligodendrocyte precursor cells (OPCs). Moreover, microglia activation following stimulation increases the expression of pro-inflammatory cytokines, such as interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α), which further exacerbate the damage to OPCs. In this study, we were the first to confirm that S100A8/A9 treatment induced the activation, proliferation and migration of the murine microglia cell line BV-2; moreover, this treatment caused the cells to switch from an anti-inflammatory activated (M2) phenotype to a pro-inflammatory activated (M1) phenotype. Meanwhile, the level of the phosphorylated nuclear factor-κB (p-NF-κB) P65 protein was remarkably elevated, and the production of pro-inflammatory factors (IL-1β, TNF-α, MMP-9) and chemokines (CCL2, CCL3, CXCL10) was also increased in the S100A8/A9-treated BV-2 microglial cells. Inhibition of NF-κB P65 phosphorylation reversed the effects of S100A8/A9 on the production of pro-inflammatory factors and chemokines. We also explored the effects of S100A8/A9 and S100A8/A9-activated BV-2 microglial cells on the viability of OPCs. The results showed that both the S100A8/A9 complex and the conditioned medium (CM) of the S100A8/A9-activated BV-2 microglial cells resulted in OPC apoptosis, which was more pronounced in the case of the CM treatment. However, OPC apoptosis in the CM group was obviously decreased through the inhibition of NF-κB p65 phosphorylation. This study indicates that S100A8/A9 induces the activation of BV-2 microglial cells and promotes the production of pro-inflammatory factors by activating the NF-κB signaling pathway, which further exacerbates OPC damage.

Remyelination is limited in patients with multiple sclerosis (MS) due to the difficulties in recruiting proliferating oligodendrocyte precursors (OPCs), the inhibition of OPC differentiation and/or maturation, and/or failure in the generation of the myelin sheath. In vitro studies have revealed that miR-219 is necessary for OPC differentiation and monocarboxylate transporter 1 (MCT1) plays a vital role in oligodendrocyte maturation and myelin synthesis. Herein, we hypothesized that miR-219 might promote oligodendrocyte differentiation and attenuate demyelination in a cuprizone (CPZ)-induced demyelinated model by regulating the expression of MCT1. We found that CPZ-treated mice exhibited significantly increased anxiety in the open field test. However, miR-219 reduced anxiety as shown by an increase in the total distance, the central distance and the mean amount of time spent in the central area. miR-219 decreased the quantity of OPCs and increased the number of oligodendrocytes and the level of myelin basic protein (MBP) and cyclic nucleotide 3 phosphodiesterase (CNP) protein. Ultrastructural studies further confirmed that the extent of demyelination was attenuated by miR-219 overexpression. Meanwhile, miR-219 also greatly enhanced MCT1 expression via suppression of oligodendrocyte differentiation inhibitors, Sox6 and Hes5, treatment with the MCT1 inhibitor -cyano-4-hydroxycinnamate (4-CIN) reduced the number of oligodendrocytes and the protein levels of MBP and CNP. Taken together, these results suggest a novel mode of action of miR-219 via MCT1 invivo and may provide a new potential remyelination therapeutic target.

BACKGROUND:Currently, there are few researches on the effect of punicalagin on the formation and differentiation of osteoclasts, and fewer researches on the mechanism of bone resorption diseases induced by wear particles. OBJECTIVE: To establish a model of titanium particles induced mouse monocyte/macrophage cel line (RAW264.7) differentiating into osteoclasts and to observe the effect of different concentrations of punicalagins on osteoclast proliferation and differentiation. METHODS: Mouse monocyte/macrophage cel lines (RAW264.7) were divided into five groups, cultured in the culture medium of common (blank group), 0.1 g/L titanium particle suspension, 0.1 g/L titanium particle suspension with 25 μmol/L punicalagins, 0.1 g/L titanium particle suspension with 50 μmol/L punicalagins, 0.1 g/L titanium particle suspension with 100 μmol/L punicalagins, respectively. The cel proliferative activity was detected by cel counting kit-8 assay at 1, 3 and 5 days. At 5 days after culture, number of osteoclasts was measured by tartrate-resistant acid phosphatase staining, the phosphorylation of IκBα and NF-κB p65 was detected by western blot assay, the mRNA expressions of nuclear factor of activated Tc1, tartrate-resistant acid phosphatase and matrix metaloproteinase-9 were measured by reverse transcription-PCR. RESULTS AND CONCLUSION:Compared with control group, titanium particles and different concentrations of punicalagin had no effect on the proliferation of RAW264.7 cels (P > 0.05). The number of tartrate-resistant acid phosphatase staining -positive cels, the phosphorylation of IκBα and NF-κB p65 as wel as the mRNA expressions of nuclear factor of activated Tc1, tartrate-resistant acid phosphatase and matrix metaloproteinase-9 were significantly increased compared with those of control group (P < 0.05,P < 0.01). And punicalagins in a concentration-dependent manner decreased the expression of the above indicators. These results indicate that punicalagin can inhibit osteoclast formation and differentiation.