灰树花干预非酒精性脂肪性肝炎的实验研究

Experimental study on intervention effect of Grifola frondosa on nonalcoholic steatohepatitis

观察灰树花对非酒精性脂肪性肝炎(NASH)的防治作用。采用高脂饲料喂养12周建立大鼠NASH模型,同时分别以0.5,1.0 g·kg-1·d-1的灰树花粉混悬液进行干预,常规HE染色观察肝组织脂肪变和炎症程度,计算NAFLD活动度积分(NAS),生化法检测血清ALT,AST以及血清和肝组织TG,CHOL水平,硫代巴比妥酸法测定肝组织MDA含量,黄嘌呤氧化酶法测定肝组织SOD活性,二硫代硝基苯甲酸法测定肝组织GSH-PX活性,ELISA法测定肝组织TNF-α,IL-6水平。结果显示,高脂饮食诱导的NASH模型组大鼠肝组织NAS,血清ALT,AST,CHOL以及肝组织TG,CHOL水平较正常组明显增高(P<0.01,P<0.05),血清TG水平较正常组明显下降(P<0.05);肝组织MDA,TNF-α,IL-6水平增高(P<0.01),而SOD,GSH-PX水平显著降低(P<0.01);不同剂量灰树花干预后,大鼠肝组织的NAS、血清ALT和肝组织TG,CHOL,MDA,TNF-α,IL-6水平较模型组明显减少(P<0.05),SOD,GSH-PX活性显著增强(P<0.05)。灰树花可能通过改善高脂饮食诱导的NASH大鼠肝脏脂质代谢紊乱,减轻氧化应激水平,降低炎症细胞因子的产生,防止NASH的进展。

To study the preventive effect of Grifola frondosa on nonalcoholic steatohepatitis （NASH）. The rat model of NASH was established by feeding high-fat diets for 12 weeks and intervened with 0. 5 g · kg^-1 · d^-1 and 1.0 g · kg^-1 · d^-1 of G. frondosa powder suspensions. The degrees of hepatocyte fatty degeneration and inflammation were observed under the optical microscope with routine HE staining. The NAFLD activity scores （NAS） were calculated. Serum ALT, AST and hepatic TG and CHOL were tested by the bio- chemical method. The hepatic MDA was examined by thiobarbituric acid method. The hepatic SOD was tested by the xanthine oxidase test. The hepatic GSH-PX activity was determined by the dithio-nitrobenzoic acid method. Hepatic TNF-α and IL-6 were detected by the enzyme-linked immunosorbent assay （ELISA）. The NASH model group induced by high-fat diets showed higher hepatic NAS, ser- um ALT, AST, CHOL and hepatic TG, CHOL, MDA, TNF-α, IL-6 （P 〈0. 01 or P 〈0. 05） and lower serum TG and hepatic SOD, GSH-PX （P 〈0. 01, P 〈0.05） than the normal control group. After being intervened with different doses of G. frondosa, the NASH group revealed significantly lower hepatic NAS, serum ALT and hepatic TG, CHOL, MDA, TNF-α and IL-6 （ P 〈 0. 05 ） and higher hepatic SOD, GSH-PX （P 〈 0.05 ） than the model group. G. frondosa may prevent the further development of NASH by improving the disorder of lipid metabolism in rats with NASH induced by high-fat diets, relieving the level of oxidative stress and reducing the genera- tion of inflammatory cytokines.