MBD5 regulates NMDA receptor expression and seizures by inhibiting Stat1 transcription.

Epilepsy is considered to result from an imbalance between excitation and inhibition of the central nervous system. Pathogenic mutations in the methyl-CpG binding domain protein 5 gene (MBD5) are known to cause epilepsy. However, the function and mechanism of MBD5 in epilepsy remain elusive. Here, we found that MBD5 was mainly localized in the pyramidal cells and granular cells of mouse hippocampus, and its expression was increased in the brain tissues of mouse models of epilepsy. Exogenous overexpression of MBD5 inhibited the transcription of the signal transducer and activator of transcription 1 gene (Stat1), resulting in increased expression of N-methyl-d-aspartate receptor (NMDAR) subunit 1 (GluN1), 2A (GluN2A) and 2B (GluN2B), leading to aggravation of the epileptic behaviour phenotype in mice. The epileptic behavioural phenotype was alleviated by overexpression of STAT1 which reduced the expression of NMDARs, and by the NMDAR antagonist memantine. These results indicate that MBD5 accumulation affects seizures through STAT1-mediated inhibition of NMDAR expression in mice. Collectively, our findings suggest that the MBD5-STAT1-NMDAR pathway may be a new pathway that regulates the epileptic behavioural phenotype and may represent a new treatment target.

Protective effect of puerarin on endothelial dysfunction of heat shock protein 60 induced specific immunity in apolipoprotein E-null mice / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To investigate the influence of endothelial dysfunction induced by inoculated dendritic cells (DCs) loaded heat shock protein 60 (HSP60) in apolipoprotein (Apo) E-null mice, and the effect of Puerarin on it.</p><p><b>METHODS</b>HSP60 DC (DChsp) acquired after prepared bone marrow-derived DCs of ApoE-null mice and treated with HSP60. In vitro, the function of DCs and the effect of Puerarin were detected. While in vivo, ApoE-null mice fed with high-cholesterol forage were divided into two groups and intravenous inoculated with DCh-sp or normal saline via vein twice respectively. The mice in the two groups were subdivided into the Puerarin group and non-treated group, and they were injected intraperitoneally with Puerarin and normal saline at the beginning of inoculation and the following 3 weeks, respectively. In addition, C57BL/6 mice without inoculation were taken as the normal control group. Two weeks after the last time inoculated, the response of T lymphocytes to HSP60 and endothelial-dependent diastolic function of aortic ring were detected.</p><p><b>RESULTS</b>HSP60 could promote DCs expressed CD86 and stimulate T lymphocytes proliferation in vitro, while Puerarin had significantly inhibitory effect. After inoculated, DChsp activated inflammatory response in vivo and aggravated endothelium-dependent dilation in mice. Puerarin could significantly inhibit inflammatory reaction caused by DChsp and improve endothelium dilation.</p><p><b>CONCLUSION</b>Hsp60 could activate DCs in vitro and in vivo, Puerarin could significantly inhibit specific immunity induced by HSP60 and improve vascular endothelium-dependent dilation.</p>