莱菔子乙醇提取物对ApoE-/-小鼠血脂血糖及肝脂肪变性的影响*

目的:探讨莱菔子乙醇提取物(AERS)对ApoE^-/-小鼠血脂血糖及肝脂肪变性的影响及其机制。方法:随机将60只ApoE^-/-小鼠分为对照组(CG)、生理盐水组(NG)、罗格列酮组(RG)、AERS治疗组,后者再分成AERS低、中、高剂量组(AERS-L/M/H),每组10只。除CG常规饲料外,其他动物均以高脂高糖高盐饲料饲养9周,CG和NG分别每天以等容量NS灌胃1次,RG每天灌胃罗格列酮(1.33 mg·kg^-1,NS稀释成等容量溶液,每次0.2 ml·10 g^-1),AERS组动物每天分别予AERS灌胃(100、300和900 mg·kg^-1)9周后。肝病理学观察,检测FPG、FIns,计算胰岛素抵抗指数(IRI)和肝系数(LC)。检测血清ALT、AST、瘦素(LEP)、TNF-α及血脂水平(TC、FFA等)。Western blot检测肝脂质代谢相关蛋白表达(HMG-R、LDL-R、LEP-R)。结果:与CG相比,NG和RG肝脏外观(色泽、肿胀情况等)和病理学(脂肪变性、肝细胞坏死等)改变明显,而AERS-M/H与CG相似;与CG相比,血清FPG、Fins、IRI、ALT、AST、TNF-α、LC、TG、LDL-C、FFA、LEP等指标明显升高(P＜0.05);与NG相比,AERS呈现剂量依赖性降低(P＜0.05);与RG相比,AERS-H的FPG、Fins明显升高(P＜0.05),而IRI明显降低(P＜0.05);与NG和RG相比,AERS组的HMG-R和LEP-R蛋白表达呈剂量依赖性减少,而LDL-R蛋白表达呈剂量依赖性增加(P＜0.05)。结论:AERS能阻止高脂高糖饲料诱导ApoE^-/^-小鼠血脂血糖升高及肝脂肪变性,其机制与减少FFA和LEP的生成,抑制TNF-α、HMG-R、LEP-R蛋白表达和促进LDL-R的蛋白表达有关。

Effects of alcohol extract of radish seed on blood lipid,glucose and liver steatosis in ApoE-/- mice

Objective: To investigate the effects and mechanisms of alcohol extract of Raphani seed (AERS) on blood lipid, blood glucose and hepatic steatosis in ApoE^-/- mice. Methods: Sixty ApoE^-/- mice were randomly divided into control group (CG), normal saline group (NG), rosiglitazone group (RG) and AERS treatment groups (AERS-L / M / H). Except CG, other groups were fed with high-fat, high-sugar and high-salt diet for 9 weeks. The mice in RG were treated with rosiglitazone (1.33 mg·kg^-1, 0.2 ml ·10 g^-1) by gavage daily. The mice in CG and NG were treated with equal volume of NS by intragastric administration daily. The mice in AERS groups were treated with AERS at the doses of 100, 300 and 900 mg·kg^-1 for 9 weeks, respectively. FPG and Fins were detected. Insulin resistance index (IRI) and liver coefficient (LC) were calculated. The levels of ALT, AST, Leptin (LEP), TNF - α and blood lipid (TC, FFA, etc.) were tested. The expressions of proteins related to liver lipid metabolism (HMG-R、LDL-R、LEP-R) were detected by Western blot. Results: Compared with NG or RG, CG showed significant changes in liver appearance (color, swelling, etc.) and pathology (steatosis, hepatocyte necrosis, etc.), while AERS-M/H groups were similar to CG. Compared with CG, the serum levels of FPG, Fins, IRI, ALT, AST, TNF-α, LC, TG, LDL-C, FFA and LEP were increased significantly (P＜0.05) . Compared with NG, AERS could decrease the above mentioned indicators in a dose-dependent manner (P＜0.05). Compared with RG, the levels of FPG and Fins of AERS-H were increased significantly, while the level of IRI was decreased (P＜0.05). Compared with NG and RG, the protein expressions of HMG-R and LEP-R in AERS groups were decreased, while the protein expression of LDL-R was increased in a dose-dependent manner (P＜0.05). Conclusion: AERS can prevent the increase of blood lipid, glucose and hepatic steatosis induced by high-fat and high-sugar diet in ApoE^-/- mice. The mechanism is related to the decrease of FFA and LEP, the inhibition of TNF-α, HMG-R, LEP-R protein expressions and the promotion of LDL-R protein expression.