大鼠脂肪干细胞对自体肝移植缺血再灌注损伤的保护机制研究

目的探讨大鼠脂肪干细胞在大鼠自体肝移植缺血再灌注(ischemia-reperfusion,IR)损伤模型中的保护作用机制。方法分离并培养大鼠脂肪干细胞(adipose-derived stem cells,ADSCs),构建稳定细胞株。SD大鼠随机分为假手术组、自体肝移植缺血再灌注组(IR组)、自体肝移植缺血再灌注+脂肪干细胞回填组(ADSCs组),每组10只。假手术组上腹正中切口,暴露并离断肝脏韧带,不做其他处理。IR组用动脉夹夹闭肝门阻断血流,肝素注射液灌注15 min,不给药。ADSCs组在肝素注射液灌注后30 min尾静脉注射1×106 ADSCs。手术后24 h后处死大鼠,检测各组大鼠血清中天冬氨酸氨基转移酶(AST)、丙氨酸转氨酶(ALT)、肝脏超氧化物歧化酶(SOD)、丙二醛(MDA)含量,以及线粒体活性;苏木素-伊红染色(HE)观察肝脏病理学改变;免疫印迹法(Western blotting)检测细胞间黏附分子-1(ICAM-1)、Bax基因表达情况。结果与假手术组相比,IR组AST和ALT水平、MDA含量较高,SOD含量较低(P0.05),线粒体活性较弱。病理切片结果显示,IR组肝细胞出现坏死,炎性细胞浸润严重。Western blotting结果显示IR组较假手术组ICAM-1、Bax表达增多。与IR组相比,ADSCs组AST和ALT水平、MDA含量较低,SOD含量较高(P0.05),线粒体活性较强,炎性细胞浸润较少,ICAM-1、Bax表达减少。结论大鼠脂肪干细胞对大鼠自体肝移植缺血再灌注损伤模型有保护作用,其作用机制可能是通过减少炎症反应和氧化应激程度进而减轻肝脏缺血再灌注损伤。

Protective effects of adipose-derived stem cells on ischemia-reperfusion injury after liver auto-transplantation in rats

Objective To investigate the protective mechanism of adipose-derived stem cells (ADSCs) on ischemia-reperfusion (IR) injury after liver auto-transplantation in rats.Methods Rat ADSCs were isolated and purified from adipose tissues of rat. Adult male SD rats were randomly divided into Sham-operated normal control group (n=10), ischemia-reperfusion injury group (IR group,n=10) and ischemia-reperfusion injury with intravenous adipose-derived stem cells group (ADSCs group,n=10). In the sham-operated group, the median incision of the upper abdomen was performed, and ligament of the liver was exposed and disconnected without any other treatment. In IR group, the portal vein was clamped by arterial clamp to block the blood lfow; heparin injection was perfused for 15 min without any administration. ADSCs group was injected with 1×106 ADSCs in the tail vein 30 min after heparin infusion. All rats were sacrificed 24 h after reperfusion. Serum aspartate transaminase (AST), alanine aminotransferase (ALT), superoxide dismutase (SOD), malondialdehyde (MDA), vitality of mitochondria were detected. The pathological changes of liver tissue were assessed with haematoxylin and eosin-stained (HE). The expression of intercellular adhesion molecule (ICAM-1), Bax were detected with Western blotting method.Results Compared with the sham-operated group, the levels of AST, ALT and MDA increased; levels of SOD and vitality of mitochondria decreased in IR group (P<0.05). Pathological results sug-gested that IR group showed necrosis of hepatocytes and severe inlfammatory cell infiltration. Western blotting results suggested that, compared with the sham-operated group, expression of ICAM-1 and Bax increased in IR group. Compared with the IR group, levels of AST, ALT and MDA decreased, levels of SOD and vitality of mito-chondria increased (P<0.05), neutrophil infiltration into the liver was fewer in ADSCs group. Compared with IR group, the expression of ICAM-1 and Bax decreased in ADSCs group.Conclusion The results indicate that AD-SCs may protect liver from ischemia-reperfusion injury in rats model. The mechanism involved in this protective effects may be related to reducing the degree of inlfammation and oxidative stress.