钙敏感受体参与高糖诱导的内皮细胞内质网应激的作用研究

Study of calcium-sensing receptor regulating endoplasmic reticulum stress induced by high glucose in endothelial cells

目的研究敏感受体(CaSR)在高糖诱导的人脐静脉内皮细胞(HUVEC)中的表达及其与内质网应激的关系。方法将HUVEC细胞分为正常糖对照组(NG组)、高糖组(HG组)、正常糖+CaSR激动剂组(NG+GdCl3组)、高糖+CaSR拮抗剂组(HG+NPS-2390组),以不同条件孵育72 h。用CCK-8法检测细胞存活率,用试剂盒检测乳酸脱氢酶、一氧化氮、脂质过氧化物、活性氧和细胞内钙离子的水平。用Western blot法检测CaSR和细胞内质网应激标志性蛋白的表达水平。结果HG组和NG+GdCl3组的细胞存活率下降,LDH漏出增多,细胞内钙离子浓度升高,CaSR蛋白表达增多,氧化应激反应增强,内质网应激标志蛋白GRP78、p-PERK、p-IRE1α蛋白表达水平增高,说明高糖和CaSR激活会导致HUVEC细胞损伤,发生内质网应激。HG+NPS-2390组细胞损伤、氧化应激和内质网应激明显减轻。结论CaSR参与了高糖导致的HUVEC细胞损伤和内质网应激,抑制CaSR,可减轻高糖导致的内皮细胞损伤。

Aim To investigate the expression of CaSR in high glucose-induced HUVECs and its relationship with endoplasmic reticulum stress.Methods HUVECs were divided into normal glucose group(NG group),high glucose group(HG group),normal glucose+CaSR agonist group(NG+GdCl3 group)and high glucose+CaSR inhibitor group(HG+NPS-2390 group).They were incubated under different conditions for 72 hours.The cell survival rate was detected by CCK8,and the levels of lactate dehydrogenase,nitric oxide,lipid peroxide,reactive oxygen species and intracellular calcium were detected by kits.The expressions of CaSR and endoplasmic reticulum stress marker proteins were detected by Western blot.Results In HG group and NG+GdCl3 group,the cell survival rates decreased,LDH leakage increased,intracellular calcium concentration increased,CaSR protein expression increased,oxidative stress aggravated,and the expression of endoplasmic reticulum stress marker proteins was up-regulated,indicating that high glucose and CaSR activation could lead to HUVEC injury and endoplasmic reticulum stress.Cell injury,oxidative stress and endoplasmic reticulum stress were significantly alleviated in HG+NPS-2390 group.Conclusions CaSR is involved in HUVEC damage and endoplasmic reticulum stress caused by high glucose.Inhibition of CaSR can reduce high glucose-induced endothelial cell injury.