米糠甾醇对非酒精性脂肪性肝炎大鼠的治疗作用

目的：研究米糠植物甾醇对非酒精性脂肪性肝炎（non-alcoholic steatohepatitis，NASH）大鼠的干预治疗作用。方法：实验选用50只健康SD雄性大鼠，随机分为正常对照组、NASH模型组和米糠甾醇低、中、高3个剂量组（65、130、195 mg/kg）。高脂饲料饲喂造模，各实验组同时进行米糠甾醇溶液灌胃干预。13周后观察各组大鼠肝组织病理学特点，测定血清中血脂总胆固醇、甘油三酯、高密度脂蛋白胆固醇、低密度脂蛋白胆固醇含量和谷丙转氨酶、谷草转氨酶、一氧化氮合酶和超氧化物歧化酶活性，并比较各组肝脏指数和脾脏指数。结果：肝脏组织切片观察到NASH模型组有明显的肝细胞脂肪变性和炎症聚集浸润，米糠甾醇各治疗组肝组织病变呈现不同程度减轻。NASH模型组血清高密度脂蛋白胆固醇含量、超氧化物歧化酶、一氧化氮合酶、谷丙转氨酶和谷草转氨酶活性与正常对照组相比，均表现出明显异常；米糠甾醇各剂量组与NASH模型组比较，血清谷丙转氨酶显著降低（P＜0.001）、谷草转氨酶/谷丙转氨酶比值显著升高（P＜0.01）；低剂量组血清超氧化物歧化酶（P＜0.05）和一氧化氮合酶（P＜0.001）显著降低；中剂量组血清高密度脂蛋白胆固醇显著升高（P＜0.05）。结论：米糠甾醇对大鼠非酒精性脂肪性肝炎有预防与治疗作用。

Rice Bran Sterol Ameliorates Non-alcoholic Steatohepatitis in Rats

Aim: To investigate the effect of rice bran sterol (RBS) on non-alcoholic steatohepatitis (NASH) in Sprague-Dawley
(SD) rats caused by feeding high-fat diet for 13 weeks. Methods: Totally 50 male SD rats were randomly assigned to control group,
NASH group and three RBS treatment groups at doses of 65, 130 mg/kg and 195 mg/kg. The NASH group and RBS treatment
groups were fed with high-fat diet and the RBS groups were administered with RBS by gavage at the same time. Two percent
Tween-80 was added to improve the solubility of RBS. After feeding for 13 weeks, serum total cholesterol (TC), triglyceride
(TG), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C) and the activities of serum
glutamic-pyruvic transaminase (ALT), glutamic-oxalacetic transaminease (AST), nitric oxide synthetase (NOS) and superoxide
dismutase (SOD) were measured, and organ indexes were compared among groups. Results: Severe steatosis in the NASH group
was observed through examining pathological slice of the liver. Serum HDL-C, SOD, NOS, ALT and AST levels in the NASH
group significantly abnormal when compared with those in the control group. Serum HDL-C level of the RBS middle-dose group
was significantly increased (P ＜ 0.05) and serum ALT levels of all RBS treatment groups were decreased (P ＜ 0.001), while AST/ALT
ratio was increased when compared with the NASH group (P ＜ 0.01). Serum SOD and NOS activities in the low-dose group
were significantly decreased when compared with those in the NASH group. Conclusion: Moderate dosage of rice bran sterol can
ameliorate NASH in rats caused by long-term high-fat diet feeding.