中国医药
中國醫藥
중국의약
CHINA MEDICINE
2011年
11期
1349-1351
,共3页
脂肪肝%表没食子儿茶素没食子酸酯%DNA甲基化转移酶%甘油三酯%葡萄糖%肝细胞
脂肪肝%錶沒食子兒茶素沒食子痠酯%DNA甲基化轉移酶%甘油三酯%葡萄糖%肝細胞
지방간%표몰식자인다소몰식자산지%DNA갑기화전이매%감유삼지%포도당%간세포
Fatty liver%Epigallocatechin-3-gallate%DNA methyltransferases%Triglyceride%Glucose%Liver cells
目的 探讨表没食子儿茶素没食子酸酯(EGCG)降低脂肪肝细胞脂肪含量的DNA甲基化调控机制,为应用EG CG防治脂肪肝提供实验依据.方法 利用游离脂肪酸棕榈酸处理大鼠正常肝细胞株BRL,建立大鼠脂肪肝细胞模型.用EGCG干预细胞72 h,检测处理前后脂肪肝细胞的脂肪含量及葡萄糖消耗量,用实时PCR方法检测EGCG作用前后DNA甲基化转移酶DNMT1、DNMT3a和DNMT3b的转录水平.结果 浓度为0.1 mmol/L的棕榈酸处理大鼠肝细胞BRL后,细胞的脂肪含量明显增加,吸光度(A)值从(0.22±0.04)增加到(0.31±0.06),差异具有统计学意义(P＜0.05),葡萄糖消耗量从(2.09±0.09)下降到(0.77±0.04),差异具有统计学意义(P＜0.01),即成功建立了脂肪肝细胞模型.EGCG干预脂肪肝细胞后,细胞的脂质含量明显减少,A值下降到(0.24±0.07) mM(P＜0.05),葡萄糖消耗量增加到(1.67 ±0.07)mM(P＜0.05),与DNA甲基化转移酶抑制剂5-Aza-2'-deoxycytidine(5-Aza-CdR)具有相同的效应.DNA甲基化转移酶DNMT1和DNMT3a基因在大鼠脂肪肝细胞中的mRNA表达水平分别增加了1.5和6倍(P＜0.05),EGCG和5-Aza-CdR均能够明显降低这两个基因的表达.DNMT3b在各处理组中没有明显差异.结论 EGCG可能通过抑制DNA甲基转移酶DNMT1和DNMT3a的表达,对脂肪和葡萄糖代谢中的关键基因去甲基化并使这些基因的表达上调,从而改善细胞内脂质沉积和胰岛素抵抗的状态.
目的 探討錶沒食子兒茶素沒食子痠酯(EGCG)降低脂肪肝細胞脂肪含量的DNA甲基化調控機製,為應用EG CG防治脂肪肝提供實驗依據.方法 利用遊離脂肪痠棕櫚痠處理大鼠正常肝細胞株BRL,建立大鼠脂肪肝細胞模型.用EGCG榦預細胞72 h,檢測處理前後脂肪肝細胞的脂肪含量及葡萄糖消耗量,用實時PCR方法檢測EGCG作用前後DNA甲基化轉移酶DNMT1、DNMT3a和DNMT3b的轉錄水平.結果 濃度為0.1 mmol/L的棕櫚痠處理大鼠肝細胞BRL後,細胞的脂肪含量明顯增加,吸光度(A)值從(0.22±0.04)增加到(0.31±0.06),差異具有統計學意義(P＜0.05),葡萄糖消耗量從(2.09±0.09)下降到(0.77±0.04),差異具有統計學意義(P＜0.01),即成功建立瞭脂肪肝細胞模型.EGCG榦預脂肪肝細胞後,細胞的脂質含量明顯減少,A值下降到(0.24±0.07) mM(P＜0.05),葡萄糖消耗量增加到(1.67 ±0.07)mM(P＜0.05),與DNA甲基化轉移酶抑製劑5-Aza-2'-deoxycytidine(5-Aza-CdR)具有相同的效應.DNA甲基化轉移酶DNMT1和DNMT3a基因在大鼠脂肪肝細胞中的mRNA錶達水平分彆增加瞭1.5和6倍(P＜0.05),EGCG和5-Aza-CdR均能夠明顯降低這兩箇基因的錶達.DNMT3b在各處理組中沒有明顯差異.結論 EGCG可能通過抑製DNA甲基轉移酶DNMT1和DNMT3a的錶達,對脂肪和葡萄糖代謝中的關鍵基因去甲基化併使這些基因的錶達上調,從而改善細胞內脂質沉積和胰島素牴抗的狀態.
목적 탐토표몰식자인다소몰식자산지(EGCG)강저지방간세포지방함량적DNA갑기화조공궤제,위응용EG CG방치지방간제공실험의거.방법 이용유리지방산종려산처리대서정상간세포주BRL,건립대서지방간세포모형.용EGCG간예세포72 h,검측처리전후지방간세포적지방함량급포도당소모량,용실시PCR방법검측EGCG작용전후DNA갑기화전이매DNMT1、DNMT3a화DNMT3b적전록수평.결과 농도위0.1 mmol/L적종려산처리대서간세포BRL후,세포적지방함량명현증가,흡광도(A)치종(0.22±0.04)증가도(0.31±0.06),차이구유통계학의의(P＜0.05),포도당소모량종(2.09±0.09)하강도(0.77±0.04),차이구유통계학의의(P＜0.01),즉성공건립료지방간세포모형.EGCG간예지방간세포후,세포적지질함량명현감소,A치하강도(0.24±0.07) mM(P＜0.05),포도당소모량증가도(1.67 ±0.07)mM(P＜0.05),여DNA갑기화전이매억제제5-Aza-2'-deoxycytidine(5-Aza-CdR)구유상동적효응.DNA갑기화전이매DNMT1화DNMT3a기인재대서지방간세포중적mRNA표체수평분별증가료1.5화6배(P＜0.05),EGCG화5-Aza-CdR균능구명현강저저량개기인적표체.DNMT3b재각처리조중몰유명현차이.결론 EGCG가능통과억제DNA갑기전이매DNMT1화DNMT3a적표체,대지방화포도당대사중적관건기인거갑기화병사저사기인적표체상조,종이개선세포내지질침적화이도소저항적상태.
Objective To investigate the regulation mechanism of DNA methylation through which tea polyphenol (-) -epigallocatechin-3-gallate (EGCG) reduces cellular fat content in a cellular model of non-alcoholic fatty liver,and supply experiment evidence for fatty liver trapping with EGCG.Methods Rat normal hepatocyte BRL was treated with PA and one of free fatty acids to establish non-alcoholic fatty liver cell model.After being treated for 72 hours using EGCG in the cell model,fat content and glucose consumption were detected.The transcription level of DNA methylation transferase DNMT1,DNMT 3a and DNMT3b were also analyzed by real time PCR.Results After rat hepatocyte BRL was treated with PA in 0.1 mmol/L,cellular fat content increased significantly.OD value from(0.22 ±0.04) to (0.31 ±0.06) and glucose consumption decrease (2.09 ±0.09) to (0.77 ±0.04),suggesting that fatty liver cell model was built up successfully.After treatment with EGCG,cellular fat content decreased and glucose consumption increased (P ＜0.01 ).DNA methylation transferase inhibitor 5-Aza-2'-deoxycytidine (5-Aza-CdR) showed the same effect.DNA metnylation transferase DNMT1 and DNMT3a,of which mRNA expression levels significantly up-regulated (1.5 fold and 6 fold) in rat fatty hepatocytes (P ＜ 0.05 ),could be reduced by both of EGCG and 5-Aza-CdR.DNMT3b was not changed among three groups.Conclusion EGCG may induce some methylation-related genes expressions which are involved in fat and glucose metabolism by suppressing the expressions of DNMTland DNMT3a,thus reversing the state of hepatic steatosis and insulin resistance.
