银杏叶提取物中三种黄酮对3T3-L1细胞成脂代谢的影响

Effects of Three Flavonoids Extracted from Ginkgo biloba on Lipid Metabolism in 3T3-L1 Cells

银杏叶提取物(EGB)包含了两大类活性成分——黄酮类和萜内酯类,并具有多种药用价值。本研究以3T3-L1细胞为研究对象,通过MTT法、油红O染色法和荧光定量PCR法研究银杏叶提取物中三种黄酮对脂肪细胞的成脂代谢影响。结果显示,山奈酚、槲皮素和异鼠李素在较高浓度下(100μmol/L)对成熟脂肪细胞的细胞毒性较为显著,分别是44%、26%和14%。山奈酚和槲皮素在100μmol/L时对前脂肪细胞的增殖抑制作用为分别27%和19%,异鼠李素对前脂肪细胞的增殖抑制效果小于5%,影响较小,以上数值均有统计学意义。油红O染色半定量结果表明异鼠李素,山奈酚和槲皮素在相同浓度下(50μmol/L)对脂质积累的抑制率分别为43%、29%和17%,且具有统计学意义。荧光定量PCR结果表明三种银杏黄酮在较高浓度下能够显著抑制细胞分化终末期的关键转录因子PPARγ、C/EBPα和SREBP-1c的表达,进而影响其下游与脂质合成相关的酶和蛋白的转录水平表达。综上,三种银杏黄酮对3T3-L1细胞的主要影响方式是对成熟脂肪的细胞毒性以及对脂肪细胞分化和脂质积累的抑制。

Ginkgo biloba extract(EGB)contains two groups of active components:flavonoid and terpenoid,and has broad pharmaceutical prospects.This study took 3 T3-L1 cells as the research object to study the effect of three flavonoids extracted from G.biloba on adipogenic metabolism by MTT,oil red O staining and fluorescence quantitative PCR.The results indicated that the cytotoxicity of kaempferol,quercetin and isorhamnetin at 100μmol/L concentration to mature adipocytes was 44%,26%and 14%,respectively.At 100μmol/L,the inhibitory effect of kaempferol and quercetin on the proliferation of preadipocytes was 27%and 19%respectively,while isorhamsin less than 5%,showing little influence,the values were all statistically significant compared to the control group.Fluorescence quantitative PCR results showed that the three flavonoids could significantly inhibit the expression of key transcription factors PPARγ,C/EBPαand SREBP-1c in the end stage of cell differentiation at higher concentration,and then affect the expression of enzymes and proteins related to lipid synthesis downstream.Above all,the three ginkgo flavones mainly affect 3t3-l1 cells through cytotoxicity to mature fat and inhibition of adipocyte differentiation and lipid accumulation.