caspase抑制剂z-VAD-fmk对阿霉素损伤乳鼠心肌细胞calumenin、caspase-3、GRP78及GRP94表达的影响

目的：研究细胞凋亡限速酶caspase广谱抑制剂z-VAD-fmk对阿霉素损伤心肌细胞calumenin、caspase-3、GRP78及GRP94表达的影响，探讨心肌细胞网腔钙结合蛋白与内质网应激及心肌细胞凋亡是否存在相互调控关系。方法：原代培养乳鼠心肌细胞实验分为3组：对照组（正常细胞）、阿霉素组（3 mg/L阿霉素+心肌细胞）、Z-VAD-fmk组（3 mg/L阿霉素+ 0.1μmol/L Z-VAD-fmk +心肌细胞），每组细胞设3个复孔，分别处理后置37℃、CO₂培养箱中培养24 h阿霉素组、z-VAD-fmk组。采用免疫组化方法检测培养乳鼠心室肌细胞α-SMA蛋白。采用Westernblot技术检测各组心肌细胞Calumenin、内质网应激伴侣蛋白GRP78、GRP94及caspase-3表达。结果：与对照组相比较，阿霉素组心肌细胞calumenin表达明显减少（P < 0.01），GRP78、GRP94及caspase-3表达增加（P < 0.01）。与阿霉素组相比较，z-VAD-fmk组心肌细胞calumenin表达增加（P < 0.01），而GRP7，GRP94及caspase-3减少（P < 0.01）。结论：caspase广谱抑制剂z-VAD-fmk增加阿霉素损伤心肌细胞calumenin表达进而缓解内质网应激。

Effects of caspase inhibitor z-VAD-fmk on the expressions of calumenin,caspase-3, GRP78 and GRP94 in adriamycin-injured cardiomyocytes

Objective: To study the effects of Caspase broad spectrum inhibitor Z-VAD-FMK on the expressions of calumenin,caspase-3, GRP78 and GRP94 in adriamycin-injured cardiomyocytes and to discuss whether there is a regulation relationship between calumenin and endo-plasmic reticulum stress and myocardial apoptosis. Methods: The primary cultured suckling mouse myocardium were randomly divided into control group (cardiomyocyte), adriamycin group (3 mg/L adriamycin + cardiomyocyte) and z-VAD-fm group (3 mg/L adriamycin + 0.1 μmol/L Z-VAD-fmk + cardiomyocyte), each group of cardiomyocytes were cultured in CO₂ incubator at 37℃ for 24 h (n=3). The expres-sion ofα -SMA protein in ventricular myocytes was detected by immunohistochemical method. The expressions of calumenin, GRP78, GRP94 and Caspase-3 in the myocardial cells were detected by Western blot. Results: Compared with the control group, the expression of calumenin in adriamycin induced myocardial cells was significantly decreased (P < 0.01), while the expressions of GRP78, GRP94 and Caspase-3 ex-pression were increased (P < 0.01). Compared with adriamycin group, the expression of calumenin in z-VAD-fm group was increased (P < 0.01), while the expressions of GRP78, GRP94 and caspase-3 were decreased (P < 0.01). Conclusion: The caspase inhibitor z-VAD-fmk inhibited the expression of caspase and increased the expression of calumenin in adriamycin induced myocardial cells, and thus alleviated the endoplasmic reticulum stress.