芦丁激活腺苷酸活化蛋白激酶α蛋白表达减轻全氟辛酸染毒小鼠肝脏损伤

Rutin activates AMPKα to ameliorate liver damage caused by perfluorooctanoic acid in mice

目的研究芦丁(rutin)对全氟辛酸(perfluorooctanoic acid, PFOA)染毒小鼠肝脏损伤的保护效应及机制。方法将24只雄性ICR小鼠随机分成3组,每组8只:对照组(双蒸水),PFOA组[PFOA 20 mg/(kg·d)],芦丁干预组[PFOA 20 mg/(kg·d)+rutin 20 mg/(kg·d)],正常饮食,经口灌胃,每日观察、称重、记录。14天后采血、处死后迅速剥离肝脏并称重。部分肝脏组织固定于4%多聚甲醛后苏木精-伊红(hematoxylin-eosin, HE)染色及糖原过碘酸希夫(periodic acid-schiff, PAS)染色;检测血清样品中谷丙转氨酶(glutamic-pyruvic transaminase, GPT)活性,以及肝脏组织匀浆中甘油三酯(triglyceride, TG)、总胆固醇(total cholesterol, TC)、丙二醛(malondialhyde, MDA)等含量和相关酶的活性等;Western blot检测腺苷酸活化蛋白激酶α(AMP-activated protein kinase, AMPKα)及磷酸化腺苷酸活化蛋白激酶α(phospho-AMP-activated protein kinaseα, p-AMPKα)的蛋白表达水平。结果 PFOA导致小鼠体重明显降低、肝脏重量与肝脏相对体重系数均显著性升高(P<0.05);肝细胞索解离,肝细胞肿胀、溶解,有明显损伤,PAS染色阳性细胞明显减少;PFOA组GPT活性为(204.63±11.26)U/L,与对照组(28.80±4.51)U/L相比显著升高(P<0.05);小鼠肝脏组织中TG、TC和MDA的含量分别为(4.89±0.51)mmol/g prot、(8.06±0.84)mmol/g prot和(315.38±60.79)nmol/mg prot,与对照组相比均明显增多(P<0.05);T-SOD活性为(4175.56±334.96)U/mg prot,与对照组比显著降低(P<0.05);芦丁干预后,与PFOA暴露组比较,小鼠体重没有显著性变化(P>0.05),但是肝重和肝脏相对体重系数显著降低(P<0.05),小鼠肝细胞肿胀情况好转,肝细胞索结构尚清,PAS染色阳性细胞明显增多,芦丁干预组GPT活性为(168.75±18.32)U/L,与PFOA组比显著下降(P<0.05);小鼠肝脏组织中TC和MDA含量分别为(4.25±0.77)mmol/g prot和(211.27±44.44)nmol/mg prot,与PFOA组比显著减少(P<0.05);T-SOD活性为(7368.88±673.09)U/mg prot,与PFOA组比显著升高(P<0.05)。三组肝脏组织中AMPKα蛋白表达无明显差异,与PFOA组相比,PFOA+rutin组的p-AMPKα蛋白表达显著上调。结论 PFOA暴露可导致小鼠肝脏损伤,引起脂质堆积。而芦丁对该损伤有一定的保护效应,这可能与芦丁激活AMPKα蛋白表达从而有效纠正TG水平以及增强抗氧化酶类的活性有关。

OBJECTIVE To study the protective effect and mechanism of rutin on perfluorooctanoic acid(PFOA)-induced liver damage in mice. METHODS A total of 24 male ICR mice were randomly divided into 3 groups, 8 in each group: control group(ctrl group: ddH2O), perfluorooctanoic acid group(PFOA group: PFOA 20 mg/(kg·d)), rutin intervention group(rutin+PFOA group: PFOA 20 mg/(kg·d)+rutin 20 mg/(kg·d)), normal diet, oral gavage, daily observation, weighting, and recording. After 14 days of treatment, the liver was quickly stripped and weighted after blood sampling and execution. Part of the liver tissue is fixed in 4% paraformaldehyde for HE staining and PAS staining;glutamic-pyruvic transaminase(GPT) activity in the sera samples and triglyceride(TG), total cholesterol(TC), malondialhyde(MDA) content in hepatic tissue homogenate, as well as the activity of some enzymes were assayed;Using western blot to detect adenylate activated protein kinase α(AMPKα) and phosphorylated adenylate-activated protein kinase α(p-AMPKα) expression levels. RESULTS PFOA caused a significant decrease in the weight of mice, a significant increase in liver weight and liver relative body weight coefficient(P<0.05), hepatocyte cord dissociation, hepatocyte swelling, dissolution, and obvious damage, and PAS staining positive result were significantly reduced. The GPT activity of the PFOA group was 204.63±11.26 U/L, which was significantly higher than that of the control group(28.80±4.51 U/L)(P<0.05);The contents of TG, TC and MDA in the liver tissues of mice were 4.89±0.51 mmol/g prot, 8.06±0.84 mmol/g prot and 315.38±60.79 nmol/mg prot, respectively, which were significantly higher than those of the control group(P<0.05);The activity of T-SOD was 4175.56±334.96 U/mg prot, which was significantly lower than that of the control group(P<0.05);After rutin intervention, compared with PFOA exposure group, the weight of the mice did not change significantly(P>0.05), however, the liver weight and the relative weight coefficient of the liver were significantly reduced(P<0.05), and the hepatocytes swollen and cell lysis were attenuated, the structure of cell cord changed clear, the positive PAS staining cells were significantly increased, the GPT activity of the rutin intervention group was 168.75±18.32 U/L, which was significantly lower than that of the PFOA group(P<0.05);The contents of TC and MDA in the liver tissues of mice were 4.25±0.77 mmol/g prot and 211.27±44.44 nmol/mg prot, respectively, which were significantly lower than those in the PFOA group(P<0.05);The T-SOD activity was 7368.88±673.09 U/mg prot, which was significantly higher than that of the PFOA group(P<0.05). There was no significant difference in AMPKα protein expression in the liver tissues of the three groups. Compared with the PFOA group, the p-AMPKα protein expression in the PFOA+rutin group was significantly up-regulated. CONCLUSION PFOA exposure can cause liver damage and lipid accumulation in mice. Rutin has a certain protective effect on this damage, which may be related to rutin’s activation of AMPKα protein expression to effectively correct TG levels and enhance the activity of antioxidant enzymes.