玉米肽对高脂饲料所致大鼠非酒精性脂肪性肝病的保护作用

Protective effect of corn peptide on nonalcoholic fatty liver disease in rats induced by high fat diet

目的了解玉米肽对非酒精性脂肪性肝病保护作用的剂量效应及其机制。方法将70只SD健康雄性大鼠随机分均为7组,即对照组、模型组、玉米肽对照(CP)组、葛根素阳性对照组、玉米肽低、中、高剂量组,适应性喂养1周后开始实验。对照组和CP组喂养普通饲料,其余喂养高脂饲料,同时对照组和模型组灌胃纯净水,CP组和玉米肽低、中、高剂量组每天灌胃玉米肽溶液(800、400、600和800 mg/kg),葛根素阳性对照组每天灌胃300 mg/kg的葛根素溶液,周期为10周。每周记录体重和一般情况等,10周后取材检测比较7组大鼠各项指标。结果与模型组相比,玉米肽三个剂量组大鼠肝指数和胰岛素抵抗指数降低(P<0.05);血清甘油三酯(triglyceride,TG)(0.59、0.42、0.34和0.28,P<0.05)、总胆固醇(total cholesterol,TC)(2.57、2.10、1.67和1.46,P<0.05)、游离脂肪酸(free fatty acid,FFA)(0.66、0.44、0.40和0.36,P<0.05)、瘦素(10.64、9.87、9.43和9.05,P<0.05)水平降低;血清白介素-6(74.61、61.66、51.12和35.68,P<0.05)与肿瘤坏死因子-α(100.18、74.13、67.44和48.46,P<0.05)水平降低;血清天门冬氨酸氨基转移酶(41.38、19.41、14.98和8.44,P<0.05)与丙氨酸氨基转移酶(25.14、13.10、11.57和7.48,P<0.05)活性降低;肝脏TG(9.89、5.55、4.73和3.13,P<0.05)、TC(1.73、0.97、0.80和0.50,P<0.05)与FFA水平(1.81、1.11、0.77和0.70,P<0.05)降低;血清丙二醛(malondialdehyde,MDA)(21.36、15.24、12.75和10.87,P<0.05)与肝脏MDA(11.87、8.27、6.33和4.98,P<0.05)水平降低;血清及肝脏超氧化物歧化酶、谷胱甘肽过氧化物酶活性升高(P<0.05),且作用效果与玉米肽干预剂量有关。肝脏体积逐渐变小,颜色由浅黄色向红棕色过渡。结论玉米肽对大鼠非酒精性脂肪性肝病的预防效果与其干预剂量有关。

OBJECTIVE To explore the dose-effect and mechanism of the protective effect of corn peptide(CP)on nonalcoholic fatty liver disease(NAFLD).METHODS Seventy male SD rats were randomly divided into control group,model group,CP group,puerarin positive control group,low-,medium-,high-dose corn peptide group,the experiment started after 1 week of adaptive feeding.The control group and CP group were fed with ordinary feed and others were fed with high-fat feed,while the control group was given intragastric administration of purified water,the CP group and the low-,medium-,high-dose corn peptide group were given intragastric administration of corn peptide(800,400,600 and 800 mg/(kg·d),respectively),and the puerarin positive control group was given intragastric administration of 300 mg/(kg·d)of puerarin,for 10 weeks.The body weight and general condition of rats were recorded every week,after 10 weeks,the indexes of 7 groups were compared.RESULTS Compared with the model group,the liver index(3.67,3.29,3.19 and 3.04,P<0.05)of the rats in the three doses of corn peptide groups decreased.The homeostasis model assessment of insulin resistance(13.66,11.82,11.55 and 10.53,P<0.05)decreased.The serum triglyceride(TG)(0.59,0.42,0.34 and 0.28,P<0.05),total cholesterol(TC)(2.57,2.10,1.67 and 1.46,P<0.05),free fatty acid(FFA)(0.66,0.44,0.40 and 0.36,P<0.05),and leptin(10.64,9.87,9.43 and 9.05,P<0.05)decreased.The serum interleukin-6(74.61,61.66,51.12 and 35.68,P<0.05)and tumor necrosis factor-α(100.18,74.13,67.44 and 48.46,P<0.05)decreased.The serum aspartate aminotransferase(41.38,19.41,14.98 and 8.44,P<0.05)and alanine aminotransferase(25.14,13.10,11.57 and 7.48,P<0.05)activity decreased.The liver TG(9.89,5.55,4.73 and 3.13,P<0.05),TC(1.73,0.97,0.80 and 0.50,P<0.05)and FFA(1.81,1.11,0.77 and 0.70,P<0.05)decreased.The serum malondialdehyde(MDA)(21.36,15.24,12.75 and 10.87,P<0.05)level and liver MDA(11.87,8.27,6.33 and 4.98,P<0.05)level decreased.The serum and liver superoxide dismutase and glutathione peroxidase activity increased(P<0.05),and the effect is related to the intervention dose of corn peptide.The size of the liver became smaller,the liver color gradually changed from light yellow to light red.CONCLUSIONCorn peptide has a certain preventive effect on NAFLD in rats,and the preventive effect of corn peptide is related to its intervention dose.