糖尿病诱导serpinE1分泌增多对心肌细胞NF-κB核易位及凋亡的影响

Effects of Diabetes-induced Increase in SerpinE1 Secretion on Nuclear Translocation of NF-κB and Apoptosis in Cardiomyocytes

目的:探讨糖尿病诱导serpinE1分泌增多是否引起心肌细胞NF-κB核易位及凋亡。方法:8周龄C57BL/6J小鼠随机分为对照组和糖尿病组,糖尿病模型应用链脲佐菌素腹腔注射诱导。体外试验中,应用低糖(5.5 mmol/L)及高糖(25 mmol/L)浓度培养基分别处理大鼠心肌H9C2细胞。ELISA法分别检测小鼠血清及细胞培养上清中的serpinE1水平,Western Blot分别检测心脏组织及细胞中caspase-3、cleaved caspase-3以及细胞浆、细胞核中NF-κB蛋白表达。此外,H9C2细胞分为三组:对照组、serpinE1重组蛋白处理组、JSH-23与serpinE1重组蛋白共同处理组,Western Blot检测上述相同指标。结果:糖尿病小鼠血清及高糖处理的细胞培养上清中serpinE1水平较对照组显著增加(P<0.05)。同对照组相比,细胞核/细胞浆NF-κB、cleaved caspase-3/caspase-3在糖尿病小鼠心肌组织及H9C2细胞高糖处理组中显著上升(P<0.05)。此外,serpinE1重组蛋白处理后细胞核/细胞浆NF-κB以及cleaved caspase-3/caspase-3同对照组相比,均显著增加(P<0.05),而JSH-23则减弱了serpinE1的这些效应。结论:糖尿病诱导serpinE1分泌增多促进心肌细胞NF-κB核易位及凋亡。

Objective: To investigate whether the increased secretion of serpinE1 induced by diabetes can cause nuclear translocation and apoptosis of NF-κB in cardiomyocytes. Methods: 8-week-old C57BL/6J mice were randomly divided into control and diabetic group. The diabetes model was induced by intraperitoneal injection of streptozotocin. In vitro, rat myocardial H9C2 cells were treated with low-glucose(5.5 mmol/L) and high-glucose(25 mmol/L) concentration media, respectively. SerpinE1 levels in mouse serum and cell culture supernatant were detected by ELISA, as well as caspase-3 and cleaved caspase-3, in line with NF-κB protein expressions in cytoplasm and nucleus in heart tissue and cells were detected by Western Blot, respectively. In addition, H9C2 cells were divided into three groups: control, serpinE1 recombinant protein, and JSH-23 combined with serpinE1 recombinant protein. Western Blot were used to detect the same indicators above. Results: SerpinE1 levels in serum of diabetic mice and cell culture supernatants treated with high glucose were significantly higher than those in control group(P<0.05). Compared with the control group, nuclear/cytoplasmic NF-κB,cleaved caspase-3/caspase-3 were significantly increased in the myocardial tissue of diabetic mice and H9C2 cells treated with high glucose(P<0.05). Moreover, the nuclear/cytoplasmic NF-κB and cleaved caspase-3/caspase-3 were significantly increased after serpinE1recombinant protein treatment compared with the control group(P<0.05), while JSH-23 treatment attenuated these effects of serpinE1.Conclusion: Diabetes-induced increase in serpinE1 secretion promotes NF-κB nuclear translocation and apoptosis in cardiomyocytes.