Department of Veterinary Internal Medicine, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, P.R. China.
Avian Pathol. 2013 Feb;42(1):32-7. doi: 10.1080/03079457.2012.757289.
Apoptosis repressor with caspase recruitment domain (ARC) is highly involved in apoptosis induced by oxidative stress or ischaemia/reperfusion injury. Furthermore, even though the exact mechanism is still unknown, some studies suggest that exogenous ARC also possesses anti-apoptotic ability. The study investigated whether mouse-derived ARC acquires anti-apoptotic ability and the pathway of regulation in chick embryo cardiomyocytes. To evaluate whether mouse-derived ARC can inhibit chick embryo cardiomyocyte apoptosis induced by hydrogen peroxide, recombinant pcDNA3.1/ARC plasmid was acquired and transfected into chick embryo cardiomyocytes. ARC-related gene (caspase-2, caspase-8, caspase-3, and caspase-9, cytochrome C, bcl-2, and XIAP) mRNA and protein expression levels were detected by real-time polymerase chain reaction and western blotting, respectively. Here we demonstrate that hydrogen peroxide induced apoptosis in chick embryo cardiomyocytes in a time-dependent manner and that this effect could be suppressed by mouse-derived ARC expression. Moreover, unlike endogenous ARC, exogenous ARC was exclusively expressed in the cytoplasm and down-regulated caspase-2, caspase-8, and caspase-3, bcl-2, and XIAP gene expression levels. However, only caspase-3 protein levels were decreased. In addition, threonine 149 phosphorylation by CK2 was required for exogenous ARC to exert an anti-apoptotic effect in chicken embryo cardiomyocytes and suggested exogenous ARC may in part share the same pathway of regulation with endogenous ARC. These results indicate that mouse-derived ARC plays an important role in protection of chick embryo cardiomyocytes against oxidative stress apoptosis by inhibiting caspase-3 mRNA and protein expression levels.
凋亡抑制因子 with caspase recruitment domain(ARC)在氧化应激或缺血/再灌注损伤诱导的细胞凋亡中起着重要作用。此外,尽管确切的机制尚不清楚,但一些研究表明,外源性 ARC 也具有抗凋亡作用。本研究探讨了鼠源性 ARC 是否具有抗凋亡能力及其在鸡胚心肌细胞中的调控途径。为了评估鼠源性 ARC 是否能抑制过氧化氢诱导的鸡胚心肌细胞凋亡,获得了重组 pcDNA3.1/ARC 质粒并转染到鸡胚心肌细胞中。通过实时聚合酶链反应和 Western blot 分别检测 ARC 相关基因(caspase-2、caspase-8、caspase-3 和 caspase-9、细胞色素 C、bcl-2 和 XIAP)的 mRNA 和蛋白表达水平。结果表明,过氧化氢能以时间依赖性方式诱导鸡胚心肌细胞凋亡,而鼠源性 ARC 的表达能抑制这一作用。此外,与内源性 ARC 不同,外源性 ARC 仅表达于细胞质中,并下调 caspase-2、caspase-8 和 caspase-3、bcl-2 和 XIAP 的基因表达水平。然而,只有 caspase-3 蛋白水平下降。此外,CK2 对 threonine 149 的磷酸化是外源性 ARC 在鸡胚心肌细胞中发挥抗凋亡作用所必需的,这表明外源性 ARC 可能与内源性 ARC 部分共享相同的调控途径。这些结果表明,鼠源性 ARC 通过抑制 caspase-3 mRNA 和蛋白表达水平,在保护鸡胚心肌细胞免受氧化应激诱导的细胞凋亡中发挥重要作用。