摘要
目的 观察二甲双胍对非酒精性脂肪肝病的干预作用及其对肝细胞脂性凋亡磷脂酶A2/溶血磷脂酰胆碱通路的影响.方法 36只雄性SD大鼠分成3组:普通饮食组(Ⅰ组)、高脂饮食组(Ⅱ组)、二甲双胍干预组(Ⅲ组)各12只,喂养10周处死,称体重、肝重,测血清谷丙转氨酶、甘油三酯、胆固醇、低密度脂蛋白胆固醇、脂蛋白(a)、空腹血糖、空腹胰岛素、游离脂肪酸、溶血磷脂酰胆碱、磷脂酶A2等,测肝脂质(肝脏甘油三酯、胆固醇),逆转录聚合酶链反应(RT-PCR)法检测肝脏磷脂酶A2 mRNA表达,观察肝组织病理变化.结果 (1)高脂饮食组肝重(g)(16.92±2.49 vs.12.16±0.82),肝指数(0.034±0.004 vs.0.026±0.002),血清谷丙转氨酶(U/L)(45.43±9.73 vs.29.42±6.73)、甘油三酯(mmol/L)(1.22±0.24 vs.0.85±0.19)、胆固醇(mmol/L)(2.00±0.37 vs.1.49±0.33)、脂蛋白(a)(mmol/L)(743.86±32.19 vs.648.42±78.87)、低密度脂蛋白胆固醇(mmol/L)(1.31±0.35 vs.0.65±0.22)、空腹胰岛素(mmol/L)(22.16±5.16 vs.16.86±5.35)、稳态模型胰岛素抵抗指数(5.10±1.45 vs.3.59±0.99)、游离脂肪酸(mEq/L)(0.57±0.10 vs.0.35±0.07)、分泌型磷脂酶A2(sPLA2)[μmol(min·ml)](0.130±0.016 vs.0.098±0.024)、溶血磷脂酰胆碱(μmol/L)(707.26±92.48 vs.508.87±96.50)、瘦素水平(pg/ml)(80.08±17.73 vs.65.儿±14.09),肝脏甘油三酯(mg/g)(13.57±0.65 vs.12.03±1.14)、胆固醇(mg/g)(2.19±0.15 vs.1.94±0.12)较普通饮食组高(P均<0.05),脂肪变性程度明显加重,sPLA2 mRNA表达显著增高.(2)二甲双胍干预组体重(g)(394.40±33.10 vs.491.86±26.45),肝重(g)(13.24±1.16 vs.16.92±2.49),血清谷丙转氨酶(U/L)(30.40±4.50 vs.45.43±9.73)、甘油三酯(mmol/L)(0.75±0.19 vs.1.22±0.24)、胆固醇(mmol/L)(1.61±0.38 vs.2.00±0.37)、空腹胰岛素(mmol/L)(16.96±5.60 vs.22.16±5.16)、稳态模型胰岛素抵抗指数(3.75±1.41 vs.5.10±1.45)、sPLA2[μmol/(min·ml)](0.101±0.009 vs.0.130±0.016)、溶血磷脂酰胆碱水平(μmol/L)(549.92±90.78 vs.707.26±92.48),肝脏甘油三酯(mg/g)(11.23±1.70 vs.13.57 ±0.65)、胆固醇(mg/g)(1.97±0.20 vs.2.19±0.15)较高脂饮食组低(P均<0.05),脂肪变性程度显著减轻,sPLA2 mRNA表达显著降低.(3)二甲双胍干预组大鼠肝指数(0.034±0.004 vs.0.026±0.002)、低密度脂蛋白胆固醇(mmol/L)(0.96±0.34vs.0.65±0.22)较普通饮食组高(P<0.05),脂肪变性程度、sPLA2 mRNA表达等差异无统计学意义(P>0.05).结论 二甲双胍对高脂饮食诱导大鼠非酒精性脂肪肝病有干预作用,其作用可能与改善胰岛素抵抗,降低分泌型磷脂酶A2基因表达,降低血清分泌型磷脂酶A2、溶血磷脂酰胆碱水平,减轻炎症反应和保护线粒体功能有关.
Objective To investigate the potential preventive effects of metformin on non-alcoholic fatty liver disease (NAFLD) and roles of phospholipase A2/lysophosphatidylcholine pathway in hepatocyte lipoapoptosis in a rat NAFLD model induced by high-fat diet. Method Male SD rats ( n = 36 ) were randomly divided into three groups with 12 rats in each and treated with different diet and drugs: group Ⅰ:ordinary diet, group Ⅱ: high-fat diet, group Ⅲ: high-fat diet and metformin. Ten weeks later, the rats were sacrificed and their body weight and liver weight were obtained, serum lipid metabolic indexes, insulin resistance indexes and secretory phospholipase A2( sPLA2 ), lysophosphatidylcholine(LPC) levels and other parameters were measured. Phospholipase A2 mRNA expression levels were measured by quantitative reverse transcription-polymerase chain reaction (RT-PCR). In addition, the histological changes of liver tissue were analyzed. Result Compared to ordinary diet group,the rat's liver weight (g) ( 16.92 ±2.49 vs. 12.16 ±0.82) ,hepatic exponent ( 0.034 ± 0.004 vs. 0.026 ± 0.002 ), serum alanine aminotransferase (U/L)(45.43 ±9.73 vs. 29.42 ± 6.73), triglyceride(mmol/L) ( 1.22 ±0.24 vs. 0.85 ±0.19) ,cholesterol (mmol/L)(2.00 ±0.37 vs. 1.49 ± 0.33),lipoprotein(a) (mmol/L) (743.86 ±32.19 vs. 648.42 ±78. 87), low-density lipoprotein (mmol/L) ( 1.31 ± 0.35 vs. 0.65 ± 0.22 ), insulin (mmol/L) ( 22.16 ±5.16 vs. 16.86 ±5.35 ),insulin resistance index(5.10 ± 1.45 vs. 3.59 ± 0.99 ),free fatty acid(mEq/L)(0.57 ± 0.10 vs. 0.35 ± 0.07 ), sPLA2 [μmol/( min · ml ) ] ( 0.130 ± 0.016 vs. 0.098 ± 0.024 ),lysophosphatidylcholine( μ mol/L) ( 707.26 ± 92.48 vs. 508. 87 ± 96. 50 ), leptin (pg/ml) ( 80.08 ± 17.73 vs. 65.11 ± 14.09 ), liver triglyceride ( mg/g ) ( 13.57 ± 0.65 vs. 12.03 ± 1.14 ), cholesterol ( mg/g ) (2.19 ±0.15 vs. 1.94 ± 0.12 ) (P 〈 0.05 ) were significantly increased in high-fat diet group. Moreover,degree of hepatic steatosis was significantly higher and sPLA2 mRNA expression was also significantly increased. Secondly,in comparison with high-fat diet group, early metformin treatment significantly reduced the rat's body weight(g) ( 394.40 ± 33.10 vs. 491.86 ± 26.45 ), liver weight(g) ( 13.24 ± 1.16 vs.16. 92 ± 2. 49 ), serum alanine aminotransferase (U/L) ( 30.40 ± 4.50 vs. 45.43 ± 9.73 ), triglyceride (mmol/L) (0.75 ±0.19 vs. 1.22 ±0.24), cholesterol (mmol/L) (1.61 ±0.38 vs. 2.00 ±0.37),insulin(mmol/L) (16. 96 ± 5.60 vs. 22.16 ± 5.16 ), insulin resistance index (3.75 ± 1.41 vs. 5.10 ±1.45 ), sPLA2 [μmol/( min·ml) ] (0.101 ±0.009 vs. 0.130 ±0.016), lysophosphatidylcholine( μmol/L) (549.92 ± 90.78 vs. 707.26 ± 92.48), liver triglyceride (mg/g) ( 11.23 ± 1.70 vs. 13.57 ± 0.65),cholesterol(mg/g) ( 1.97 ±0.20 vs. 2.19 ±0.15 ) ( P 〈0.05 ). Moreover, degree of hepatic steatosis was significantly lower and sPLA2 mRNA expression was also significantly decreased by metformin. Thirdly ,when compared to ordinary diet group, metformin could also significantly increase hepatic expotent (0.034 ±0.004 vs. 0.026 ± 0.002 ) and low-density lipoprotein level (mmol/L) ( 0.96 ± 0.34 vs. 0.65 ± 0.22 )(P〈0.05). However, it had no impact on hepatic steatosis and sPLA2 expression (P 〉 0.05 ).Conclusion It was indicated that metformin has potent effects on improving lipid metabolism and insulin resistance in high-fat diet induced non-alcoholic fatty liver disease rat model. The liver protective mechanisms of metformin in non-alcoholic fatty liver disease may be contributed to down-regulation of secretory phospholipase A2 mRNA expression, decrease in serum secretory phospholipase A2,lysophosphatidylcholine, lower inflammatory response and protect mitochondrial function.
出处
《中华儿科杂志》
CAS
CSCD
北大核心
2011年第2期139-145,共7页
Chinese Journal of Pediatrics
基金
卫生部科学研究基金一浙江省医药卫生重大科技计划项目(WKJ2008-2-026)
浙江省自然科学基金(Y2080047)
“十一五”国家科技支撑计划(2009BA180800)
作者简介
现在工作单位:317000浙江肯台州医院儿科