JAK2/STAT3调节抗增殖蛋白表达在H_2S后处理心肌细胞中的保护作用

Role of JAK2 /STAT3-regulated prohibitin in cardioprotection of H_2S postconditioning in hypoxia /reoxygenation-treated cardiomyocytes

目的探讨JAK2/STAT3信号通路是否通过调节抗增殖蛋白而在硫化氢(H2S)后处理中减轻缺氧/复氧(H/R)心肌细胞的损伤。方法体外培养的原代新生大鼠心肌细胞建立缺氧/复氧损伤模型。随机分为6组:正常对照组(Normal组)、缺氧/复氧组(H/R组)、硫化氢后处理组(NP组)、硫化氢后处理+AG490组(N+A组)、AG490组(AG组)、溶媒组(DMSO组)。分别在缺氧前、复氧2 h检测心肌细胞的存活率、培养液中LDH的释放;复氧末,采用流式细胞术观察各组心肌细胞的凋亡情况;应用Western blot方法检测tSTAT3、p-STAT3、PHB蛋白的表达情况。结果缺氧前,组间各个指标检测值差异未见统计学意义(P>0.05)。复氧2h,与H/R组比较,NP组心肌细胞存活率明显提高了(P<0.05),LDH的释放以及细胞凋亡率明显降低(P<0.05);同时p-STAT3、PHB蛋白表达水平明显升高。AG490逆转了H2S后处理产生的心肌保护效应,使N+A组细胞活力及pSTAT3、PHB的表达水平降低(P<0.05),细胞凋亡率明显增加(P<0.05)。结论 JAK2/STAT3信号通路可能通过上调抗增殖蛋白的表达而在硫化氢(H2S)后处理中减轻心肌细胞缺氧/复氧损伤。

Aim ToinvestigatewhethertheJAK2/STAT3 signaling pathway regulates prohibitin expres-sion to protect cardiomyocytes against hypoxia/reoxy-genation injury in hydrogen sulfide postconditioning. Methods Primaryculturedcardiomyocytesfromneo-natal rats were divided into 6 groups： control group （ Normal） , hypoxia/reoxygenation group （ H/R ） , hy-drogen sulfide postconditioning group （ NP） , hydrogen sulfide with AG490 group （ N ＋ A ） , AG490 group （ AG） , DMSO group （ DMSO） . The survival percent-age of cardiomyocytes and the release of LDH were tested at pre-hypoxia and reoxygenation 2h. After reox-ygenation, cell apoptosis was detected by flow cytome-try. The expression of t-STAT3, p-SATAT3 and PHB were determined with Western blot analysis. Results No obvious changes were observed among the groups before hypoxia （P 〈0. 05）. After reoxygenation 2h, compared with H/R group, NP group significantly im-proved the survival rate of cardiomyocytes （ P 〈0. 05 ） , inhibited the release of LDH and the myocardi-al apoptosis （ P 〈0. 05 ） , meanwhile up-regulated the p-STAT3 and PHB expression. However, AG490 abol-ished the cardioprotection offered by hydrogen sulfide postconditioning and the increase in p-STAT3 and PHB expression.Conclusion Hydrogensulfidepostcondi-tioning may protect cardiomyocytes against hypoxia/reoxygenation injury through the JAK2/STAT3 pathway upregulating the expression of prohibitin.