高糖对脂多糖诱导的大鼠肺微血管内皮细胞自噬的影响

Effects of high glucose on autophagy in lipopolysaccharides-exposed rat pulmonary microvascular endothelial cells

目的:探究高糖(HG)环境对脂多糖(LPS)处理的大鼠肺微血管内皮细胞(RPMECs)自噬的影响。方法:LPS联合HG处理RPMECs 24 h后;相应商品化试剂盒检测细胞活力、乳酸脱氢酶(LDH)含量、超氧化物歧化酶(SOD)活性及丙二醛(MDA)含量。免疫印迹法检测Beclin-1、微管相关蛋白1轻链3Ⅱ(LC-3Ⅱ)、GAPDH蛋白表达水平。结果:HG或LPS处理可导致RPMECs增殖活力、SOD含量显著降低,而LDH释放量、MDA含量及Beclin-1、LC-3Ⅱ蛋白表达水平显著升高;HG联合LPS处理可进一步导致上述变化。结论:HG可加重LPS诱导的RPMECs损伤,其机制与氧化应激增强及自噬功能过度活化密切相关。

Objective:To investigate the effects of high glucose(HG) on autophagy induced by lipopolysaccharides(LPS) in rat pulmonary micro vascular endothelial cells(RPMECs).Methods:RPMECs were exposed to LPS for 24 hours under HG conditions.Then,cellular viability,lactate dehydrogenase(LDH) concentration,super oxide dismutase(SOD) activity,malondialdehyde(MDA) concentration were detected by commercial kits,respectively.The expression of Beclin-1,microtubule-associated protein 1 light chain 3 Ⅱ(LC-3 Ⅱ),and GAPDH were analyzed by Western Blot.Results:HG or LPS induced significant decrease in the cellular viability and SOD activity,accompanied with significant increase in LDH/MDA generation,and Beclin-1/LC-3 Ⅱ expression in RPMECs,respectively,and the HG combined with LPS aggravated the above trends.Conclusion:HG could exacerbate LPS-induced injury in RPMECs.And the mechanisms might be associated with the upregulation of oxidative stress and autophagy.