蓝莓花青素干预肝硬化大鼠肝组织凋亡蛋白表达的变化

Modulation of apoptotic protein expression by blueberry anthocyanin in rats with diethylnitrosamine-induced liver cirrhosis

目的研究蓝莓花青素干预肝硬化大鼠肝组织凋亡蛋白表达的变化。方法随机将30只大鼠分为对照组、模型组和实验组。采用二乙基亚硝胺腹腔注射法制备肝硬化模型,在其中一组给予蓝莓花青素灌胃干预,在实验第8周末,取血和肝组织。采用Western blot法检测肝组织c-caspase-3、Bax和Bcl2蛋白表达,取肝组织匀浆检测丙二醛(MDA)和超氧化物歧化酶(SOD)含量。结果组织病理学检查提示,肝硬化模型制备成功;模型组动物血清丙氨酸氨基转移酶(ALT)、天冬氨酸氨基转移酶(AST)、肿瘤坏死因子-α(TNF-α)和转化生长因子-β(TGF-β)水平分别为(579.87±20.37)U/L、(428.58±18.25)U/L、(2.56±0.18)ng/L和(2.12±0.15)ng/L,显著高于对照组[分别为(102.47±3.25)U/L、(104.45±3.87)U/L、(0.81±0.05)ng/L和(0.92±0.07)ng/L,P<0.05],而经过蓝莓花青素处理后,动物血清上述指标显著降低【分别为(371.89±14.72)U/L、(148.71±6.34)U/L、(1.73±0.11)ng/L和(1.45±0.12)ng/L,P<0.05】,模型动物血清白蛋白水平为(30.69±2.58)g/L,显著低于对照组【(37.68±3.08)g/L,P<0.05】,蓝莓花青素处理组升高至【(34.71±3.34)g/L,P<0.05】;模型组肝组织匀浆MDA水平为(0.49±0.11)μmol/L,显著高于对照组【(0.06±0.01)μmol/L,P<0.05】,SOD水平为(0.34±0.09)U/mg,显著低于对照组【(0.98±0.21)U/mg,P<0.05】,而蓝莓花青素处理组肝组织匀浆MDA水平显著降低至【(0.17±0.03)μmol/L,P<0.05】,SOD水平显著升高至【(0.71±0.19)U/mg,P<0.05】;模型动物肝组织Bcl-2表达量为(0.48±0.03),而Bad和c-caspase-3表达量分别为(1.50±0.18)和(1.41±0.17),分别较对照组显著降低或升高【分别为(1.76±0.18)、(0.41±0.02)和(0.28±0.01),P<0.05】,而经过蓝莓花青素处理动物肝组织Bcl-2表达显著增强,Bad和c-caspase-3表达显著减弱【分别为(1.47±0.14)、(0.64±0.05)和(0.50±0.05),P<0.05】。结论蓝莓花青素能够降低二乙基亚硝胺诱导的肝硬化大鼠肝组织氧化应激损伤,调节凋亡蛋白表达,抑制肝细胞凋亡,达到保护肝功能的作用。

Objective The aim of this study was to explore the effects of blueberry anthocyanin on hepatic tissue apoptotic protein expression in rats with diethylnitrosamine(DEN)-induced liver cirrhosis(LC).Methods 30 SD rats were selected and randomly divided into control,model and blueberry anthocyanin-intervened group,with 10 rats in each group.The model of LC was established by intraperitoneally injection of DEN at dose of 75 mg.kg-1.d-1 for eight weeks,and the blueberry anthocyanin solution was intragastrically administered at 50 mg.kg-1.d-1.At the end of 8 weeks,the rats were sacrificed,and sera and liver tissues were obtained.The malonaldehyde(MDA)and superoxide dismutase(SOD)in liver and expression ofBcl-2,Bad and c-caspase-3 were detected by Western bloting.Results The model was successfully built up by pathological examination.Serum ALT,AST,tumor necrosis factor-α(TNF-α)and transforming growth factor-β(TGF-β)levels in model group were(579.87±20.37)U/L,(428.58±18.25)U/L,(2.56±0.18)ng/L and(2.12±0.15)ng/L,significantly higher than[(102.47±3.25)U/L,(104.45±3.87)U/L,(0.81±0.05)ng/L and(0.92±0.07)ng/L,respectively,P<0.05],while all of them greatly decreased in blueberry anthocyanin-intervened【(371.89±14.72)U/L,(148.71±6.34)U/L,(1.73±0.11)ng/L and(1.45±0.12)ng/L,respectively,P<0.05】,serum albumin level in model group was(30.69±2.58)g/L,significantly lower than【(37.68±3.08)g/L,P<0.05】in control,while it increased to【(34.71±3.34)g/L,P<0.05】in blueberry anthocyanin-intervened;hepatic homogenate MDA level in model was(0.49±0.11)μmol/L,significantly higher than【(0.06±0.01)μmol/L,P<0.05】in control,and hepatic homogenate SOD was(0.34±0.09)U/mg,significantly lower than【(0.98±0.21)U/mg,P<0.05】in the control,while homogenate MDA level in blueberry anthocyanin-intervened group decreased to【(0.17±0.03)μmol/L,P<0.05】and SOD level increased to【(0.71±0.19)U/mg,P<0.05】;hepatic tissue Bcl-2 expression in model group was(0.48±0.03),while Bad and c-caspase-3 expression were(1.50±0.18)and(1.41±0.17),all of them significantly decreased or increased as compared to【(1.76±0.18),(0.41±0.02)and(0.28±0.01),respectively,P<0.05】in the control group,while hepatic tissue Bcl-2 express intensified,and Bad as well as c-caspase-3 expression much weaken in blueberry anthocyanin-intervened group【(1.47±0.14),(0.64±0.05)and(0.50±0.05),P<0.05】.Conclusions Blueberry anthocyanin has some liver function protective effect in rats with DEN-induced liver cirrhosis,which might be related to hepatic oxidative stress reduction and modulation of apoptotic proteins.