HIF-1α SUMOylation affects the stability and transcriptional activity of HIF-1α in human lens epithelial cells
HIF-1α SUMOylation affects the stability and transcriptional activity of HIF-1α in human lens epithelial cells
复制标题
HIF-1 α SUMO 化影响人晶状体上皮细胞中 HIF-1 α 的稳定性和转录活性
DOI：
10.1007/s00417-015-2999-x
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发表时间：
2015-08-01
影响因子：
2.7
通讯作者：
Yan, Qi-Chang
中科院分区：
文献类型：
--
作者：
Han, Xiao;Wang, Xin-Ling;Yan, Qi-Chang
高血糖可引起氧化损伤，导致糖尿病性白内障。氧化应激通过诱导包括HIF-1 α转录信号在内的多种信号通路来减轻晶状体的损伤。在培养的人透镜上皮细胞（HLECs）中，HIF-1 α SUMO化是否能增加HIF-1 α的活化，或者高糖是否能影响HIF-1 α的SUMO化，以及HIF-1 α SUMO化在高糖诱导的HLECs氧化损伤中的作用仍然是未知的。在本研究中，我们研究了相扑和相扑E3（Cbx 4和PIASy）的表达，并研究SUMO或SUMO E3过表达对HLEC中HIF-1 α SUMO化的促进作用正常对照组、高糖1组和高糖2组分别给予25 mmol/l和50 mmol/l终末葡萄糖。RT-PCR和Western blot检测SUMO 1 similar to 4、Cbx 4、PIASy、HIF-1 alpha、GLUT 1和VEGFA在mRNA和蛋白水平的表达。通过免疫荧光和共免疫荧光检测蛋白表达定位和共定位。免疫印迹分析SUMO过表达、SUMO E3过表达和蛋白酶体抑制剂MG 132对HIF-1 α稳定性和转录活性的影响。它还增加了HIF-1 α，GLUT 1和VEGFA的表达。高糖诱导的HIF-1 α与SUMO的共定位主要在细胞核内。进一步研究表明SUMO或SUMO E3过表达可增强HLEC中HIF-1 α的稳定性和转录活性。蛋白酶体抑制剂MG 132可保护SRA 01/04细胞中HIF-1 α的稳定性和转录活性，HIF-1 α SUMO化影响培养的人透镜上皮细胞中HIF-1 α的稳定性和转录活性; SUMO过表达或SUMO E3过表达增强了HIF-1 α的表达，HIF-1 α参与抑制细胞凋亡和保护透镜混浊，并且可能在保护晶状体免受糖尿病性白内障中起关键作用。
High blood glucose can induce oxidative damage and result in diabetic cataract. Oxidative stress induces various signal pathways including HIF-1 alpha transcriptional signal to attenuate the damage of lenses. Whether HIF-1 alpha SUMOylation can increase the activation of HIF-1 alpha or if high glucose can affect the SUMOylation of HIF-1 alpha in cultured human lens epithelial cells (HLECs) is still unknown, as well as the function of HIF-1 alpha SUMOylation in oxidative damage induced by high glucose in HLECs. In the present study, we examined SUMO and SUMO E3 (Cbx4 and PIASy) expression induced by high glucose, and investigated SUMO or SUMO E3 overexpression that enhanced HIF-1 alpha SUMOylation in HLECs.SRA01/04 cells, one kind of human lens epithelial cell line, were addressed in media with 5.5 mmol/l (normal control group), 25 mmol/l (high glucose1 group) and 50 mmol/l (high glucose2 group) final glucose respectively. Expression of SUMO1 similar to 4, Cbx4, PIASy, HIF-1 alpha, GLUT1, and VEGFA were detected in the mRNA and protein levels by RT-PCR and Western blot analysis. Protein expression localization and co-localization were examined by immunofluorescence and co-immunofluorescence. The effects of SUMO overexpression, SUMO E3 overexpression, and Proteasome inhibitor MG132 respectively on the stability and transcriptional activity of HIF-1 alpha were analyzed by immunoblot.High glucose treatment induced SUMO1-4 expression and enhanced the expression of Cbx4 and PIASy. It also increased the expression of HIF-1 alpha, GLUT1, and VEGFA. The co-localization of HIF-1 alpha and SUMO was mainly in the nucleus induced by high glucose. Further studies showed that SUMO overexpression or SUMO E3 overexpression could enhance HIF-1 alpha stability and transcriptional activity in HLECs. Proteasome inhibitor MG132 protected the stability and transcriptional activity of HIF-1 alpha in the SRA01/04 cells.HIF-1 alpha SUMOylation affected the stability and transcriptional activity of HIF-1 alpha in cultured human lens epithelial cells; SUMO overexpression or SUMO E3 overexpression enhanced the expression of HIF-1 alpha, which is involved in inhibiting cell apoptosis and protecting lens opacification, and presumably plays a key role in protecting lenses from diabetic cataract.