诱导HO-1改善氧化应激状态减轻老年供肝缺血一再灌注损伤

目的观察诱导血红素氧合酶-1(HO-1)生成能否减轻老年供肝移植后缺血一再灌注损伤。方法取老年(16个月龄)SD大鼠5只和成年(3个月龄)大鼠5只，分别测定其肝脏组织中超氧化物歧化酶(SOD)和过氧化氢酶(CAT)的活性及维生素E(VitE)、维生素C(VitC)和丙二醛(MDA)含量；另取老年SD大鼠60只作为供体，随机均分为血晶素(Hemin)组和对照组．分别于取肝前24h腹腔注射Hemin或生理盐水，然后将其肝脏移植给同种大鼠，同时观察再灌注后肝脏组织学变化和细胞凋亡。结果老年大鼠肝脏组织中SOD活性明显低于成年大鼠，VitC含量亦少(P＜O．05)，而MDA明显增高(P＜O．05)。用Hemin预处理的老年SD大鼠供肝在切取前，SOD活性增加．VitE、VitC含量增加．MDA含量降低(P＜O．05)；肝移植后血清ALT明显降低．肝组织HO-1活性明显增高，肝脏组织学检查示再灌注后凋亡细胞明显减少(P＜O．05)。结论老年SD大鼠肝脏存在氧化应激和脂质过氧化状态，HO-1可通过改善这种状态而减轻其缺血一再灌注损伤。

Alleviating Ischemia Reperfusion Injury in Aged Liver by Inducing of Heme Oxygenase-1: Ameliorating Oxidative Stress

Objective To investigate whether heme oxygenase 1 can alleviate the ischemia reperfusion injury of the aged donor liver. Methods The activity of superoxide dismutase (SOD) and catalase (CAT), and the contents of tocopherol (Vit E), ascorbic acid (Vit C) and malondialdehyde (MDA) were measured in the livers of adult SD rats ( n =5) and aged SD rats ( n =5). The experimental aged donor group ( n =30) received intraperitoneal injection of Hemin 24 hours before operation, the control aged donor group( n =30) received saline. The histologic changes and apoptosis in the donor liver were observed. Results The activity of SOD and the contents of Vit E and Vit C decreased significantly in 5 aged rats( P <0.05), but the content of MDA increased( P <0.05). Before the harvesting of the grafts, the activity of SOD and the contents of Vit E and Vit C increased significantly in rats pretreated with Hemin ( P <0.05) and the content of MDA decreased( P <0.05). The apoptotic cells in the livers pretreated with Hemin also decreased significantly after reperfusion( P <0.05). Conclusion The liver of aged rat presents oxidative stress and peroxidative state. Ischemia reperfusion injury can be alleviated by the induction of HO 1.