茯苓多糖对ApoE^(-/-)AS小鼠肝脏脂质沉积及胆固醇逆向转运相关蛋白表达的影响

Effects of Pachyman on Liver Lipid Deposition And Expression of Reverse Cholesterol Transport Related Proteins in ApoE^(-/-)as Mice

目的探讨茯苓多糖对载脂蛋白E基因敲除(ApoE^(-/-))动脉粥样硬化(Atherosclerosis,AS)小鼠肝脏脂质沉积及胆固醇逆向转运的影响。方法采用随机数字表法将30只ApoE^(-/-)小鼠随机分为模型组、茯苓多糖组、辛伐他汀组,每组10只,10只C57BL/6J小鼠作为正常组。正常组给予基础饲料喂饲,其余小鼠给予高脂饲料喂饲12周。茯苓多糖组以0.2 g/kg/d灌胃,辛伐他汀组以2.275 mg/kg/天灌胃,正常组和模型组给予等体积生理盐水灌胃,共干预4周。全自动生化分析仪检测小鼠血清三酰甘油(TG)、总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)、高密度脂蛋白胆固醇(HDL-C)水平,苏木素-伊红(HE)染色观察小鼠肝脏病理形态学变化,油红O染色观察小鼠肝脏脂质沉积情况,ELISA检测各组小鼠血清载脂蛋白A1(ApoA1)、对氧磷酶-1(PON1)含量,Real-time RT-qPCR法及Western Blot法检测肝脏胆固醇酯转运蛋白(CETP)、磷脂转运蛋白(PLTP)、卵磷脂胆固醇酰基转移酶(LCAT)mRNA及蛋白表达。结果与正常组比较,模型组小鼠血清TG、TC、LDL-C含量均明显上升,HDL-C含量明显下降(P<0.01),肝细胞脂肪变性明显,肝脏脂质沉积明显,小鼠血清ApoA1、PON1含量均明显下降(P<0.01),小鼠肝脏CETP、PLTP mRNA及蛋白表达明显上升,LCAT mRNA及蛋白表达明显下降(P<0.01)。与模型组相比,茯苓多糖组血清TG、TC、LDL-C含量均显著下降(P<0.01),HDL-C含量呈上升趋势(P>0.05),肝细胞脂肪变性、脂质沉积程度均有所减轻,茯苓多糖组ApoA1含量明显上升(P<0.01),PON1含量呈上升趋势(P>0.05),茯苓多糖组CETP、PLTP mRNA及蛋白表达有所下降,LCAT mRNA及蛋白表达有所上升(P<0.05,P<0.01)。结论茯苓多糖可能通过调控血脂水平与胆固醇逆向转运过程,改善ApoE^(-/-)AS小鼠肝脏脂质沉积,进而发挥防治AS作用。

Objective To explore the effects of pachyman on liver lipid deposition and reverse cholesterol transport in ApoE^(-/-)atherosclerosis mice.Methods 30 ApoE^(-/-)mice were randomly divided into model group,pachyman group and simvastatin group,with 10 mice in each group,and 10 C57BL/6J mice as control group.The control group was fed with basal diet and the rest mice were fed with high-fat diet for 12 weeks.Pachyman group was given 0.2 g/kg/d by gavage,simvastatin group was given 2.275 mg/kg/d.Control group and model group were given equal volume of normal saline for 4 weeks.The contents of serum triacylglycerol(TG),total cholesterol(TC),low density lipoprotein cholesterol(LDL-C)and high density lipoprotein cholesterol(HDL-C)were measured by automatic biochemical analyzer.The liver pathological changes were observed by hematoxylin eosin(HE)staining,lipid deposition in mice liver by oil red O staining.The contents of ApoA1 and PON1 in serum of mice in each group were detected by ELISA.The mRNA and protein expressions of LCAT,PLTP and CETP in liver were detected by Real-time RT-qPCR and Western blot.Results Compared with the control group,the serum TG,TC,LDL-C levels of the model group were significantly increased;HDL-C levels were significantly decreased(P<0.01);hepatocyte steatosis was obvious;liver lipid deposition was obvious;serum ApoA1 and PON1 levels were significantly decreased(P<0.01);and the expression of CETP,PLTP mRNA and protein in mouse liver increased significantly;and the expression of LCAT mRNA and protein decreased significantly(P<0.01).Compared with the model group,the levels of serum TG,TC,LDL-C in pachyman group were significantly decreased(P<0.01);HDL-C level showed an upward trend(P>0.05);the degree of hepatocyte steatosis and lipid deposition were reduced;the level of ApoA1 was significantly increased(P<0.01);PON1 level was increased(P>0.05);and the expression of CETP,PLTP mRNA and protein decreased in pachyman group;the expression of LCAT mRNA and protein increased(P<0.05,P<0.01).Conclusion Pachyman can improve the liver lipid deposition of ApoE^(-/-)as mice by regulating the lipid level and reverse cholesterol transport process,and then play an antiatherosclerotic role.