Henan eye Institute, Henan key laboratory of keratopathy, Zhengzhou, China.
Henan Eye Hospital, Zhengzhou, China.
Sci Rep. 2016 Sep 12;6:32850. doi: 10.1038/srep32850.
The purpose of this study was to evaluate the correlation of expression of phosphorylated methyl-CpG binding protein 2-Ser421 (MeCP2-S421) and VEGF in the membranes of patients with PDR. We examined the expression of phospho-MeCP2-S80, S421, VEGF and PEDF in surgically excised PDR membranes from 33 patients with diabetes, and idiopathic epiretinal membranes from 11 patients without diabetes, using immunohistochemistry and western blot. The colocalization of MeCP2-S421 with VEGF, PEDF, CD31, GFAP and αSMA was revealed by fluorescent double labeling. The effect of CoCl2 and knock down MeCP2 using specific siRNA on the expression of MeCP2 and VEGF were analyzed in HUCAC cells by Western blot. We found that phospho-MeCP2-S421 was significantly increased in the membranes from the patients with PDR compared with the specimens from patients without diabetes (P < 0.01). The expression of phospho-MeCP2-S421 was much stronger than that of phospho-MeCP2-S80 in the PDR membranes. Double labeling showed that the high phospho-MeCP2-S421 expression was associated with strong expression of VEGF, but not PEDF. Further, phospho-MeCP2-S421 and VEGF were increased by the stimulation of CoCl2 and knock down MeCP2 inhibited the expression of VEGF. Our result suggests that phospho-MeCP2-S421 might involve in the pathogenesis of PDR.
本研究旨在评估磷酸化甲基-CpG 结合蛋白 2-丝氨酸 421（MeCP2-S421）和 VEGF 在 PDR 患者膜中的表达的相关性。我们使用免疫组织化学和 Western blot 检测了 33 例糖尿病患者的 PDR 膜和 11 例无糖尿病的特发性视网膜前膜中磷酸化 MeCP2-S80、S421、VEGF 和 PEDF 的表达。通过荧光双重标记显示 MeCP2-S421 与 VEGF、PEDF、CD31、GFAP 和 αSMA 的共定位。通过 Western blot 分析 CoCl2 和特异性 siRNA 敲低 MeCP2 对 HUCAC 细胞中 MeCP2 和 VEGF 表达的影响。我们发现，与无糖尿病患者的标本相比，PDR 患者的膜中磷酸化 MeCP2-S421 明显增加（P<0.01）。在 PDR 膜中，磷酸化 MeCP2-S421 的表达明显强于磷酸化 MeCP2-S80。双重标记显示，高磷酸化 MeCP2-S421 表达与 VEGF 的强表达相关，但与 PEDF 无关。此外，CoCl2 的刺激增加了磷酸化 MeCP2-S421 和 VEGF，敲低 MeCP2 抑制了 VEGF 的表达。我们的结果表明，磷酸化 MeCP2-S421 可能参与了 PDR 的发病机制。
