Zhao Hong, Xu Mei, Chu Guilan
Department of Pediatrics, Tianjin Medical University General Hospital, Tianjin 300052, P.R. China.
Mol Med Rep. 2017 May;15(5):2727-2731. doi: 10.3892/mmr.2017.6341. Epub 2017 Mar 16.
The present study aimed to investigate the association between myocardial cell apoptosis and calpain-1/caspase-3 expression in a rat model of hypoxic-ischemic brain damage (HIBD). A total of 64 newborn rats were divided into control (n=8; sacrificed on day 7) and HIBD groups (n=56). HIBD group rats were sacrificed 2, 12 or 24 h, or 2, 3, 5 or 7 days following HIBD (n=8/group). A terminal deoxynucleotidyl transferase dUTP nick-end labeling assay was performed to detect myocardial apoptotic cells and calculate the apoptosis index (AI), reverse transcription-polymerase chain reaction was performed to detect myocardial calpain-1/caspase-3 mRNA expression levels and a western blot analysis was conducted to detect calpain‑1 protein expression levels. The correlations between calpain‑1 and caspase‑3 expression levels and AI were analyzed. The results demonstrated that apoptotic myocardial cells in the HIBD groups were markedly increased compared with the control group, with AI peaking in the day 3 group. Caspase‑3 and calpain‑1 mRNA expression levels were increased from 2 and 12 h following HIBD, respectively, with the most elevated levels in the day 2 group. Compared with the control group, calpain‑1 protein expression levels were increased from 2 h, with the greatest expression levels in the day 3 group (P<0.05). Calpain‑1 mRNA and protein (76/80 kDa) expression levels demonstrated positive linear correlations with AI (r=0.786, P=0.001; and r=0.853, P=0.001, respectively) Caspase-3 mRNA expression levels were positively correlated with AI (r=0.894; P=0.001). In conclusion, the present study demonstrated that in rats with HIBD, there is a positive correlation between increased apoptosis of myocardial cells and expression levels of calpain-1 and caspase-3.
本研究旨在探讨缺氧缺血性脑损伤（HIBD）大鼠模型中心肌细胞凋亡与钙蛋白酶-1/半胱天冬酶-3表达之间的关联。总共64只新生大鼠被分为对照组（n = 8；于第7天处死）和HIBD组（n = 56）。HIBD组大鼠在HIBD后2、12或24小时，或2、3、5或7天处死（每组n = 8）。进行末端脱氧核苷酸转移酶dUTP缺口末端标记试验以检测心肌凋亡细胞并计算凋亡指数（AI），进行逆转录-聚合酶链反应以检测心肌钙蛋白酶-1/半胱天冬酶-3 mRNA表达水平，并进行蛋白质印迹分析以检测钙蛋白酶-1蛋白表达水平。分析了钙蛋白酶-1和半胱天冬酶-3表达水平与AI之间的相关性。结果表明，与对照组相比，HIBD组的凋亡心肌细胞明显增加，AI在第3天组达到峰值。半胱天冬酶-3和钙蛋白酶-1 mRNA表达水平分别在HIBD后2和12小时开始升高，在第2天组中水平最高。与对照组相比，钙蛋白酶-1蛋白表达水平从2小时开始升高，在第3天组中表达水平最高（P<0.05）。钙蛋白酶-1 mRNA和蛋白（76/80 kDa）表达水平与AI呈正线性相关（分别为r = 0.786，P = 0.001；和r = 0.853，P = 0.001）。半胱天冬酶-3 mRNA表达水平与AI呈正相关（r = 0.894；P = 0.001）。总之，本研究表明，在HIBD大鼠中，心肌细胞凋亡增加与钙蛋白酶-1和半胱天冬酶-3的表达水平之间存在正相关。
