游离脂肪酸对肝细胞ACSL1表达及相关脂代谢的影响

EFFECT OF FREE FATTY ACIDS ON LONG-CHAIN ACYL-COA SYNTHETASE 1 EXPRESSION LEVEL AND LIPID METABOLISM IN LIVER CELLS

目的研究游离脂肪酸(FFA)的诱导对L02肝细胞长链脂酰CoA合成酶1(ACSL1)的表达及相关代谢的影响。方法用含不同浓度(0.2、0.4、0.8 mmol/L)FFA的培养液诱导L02细胞48 h,Western blot检测ACSL1蛋白水平,荧光定量PCR检测ACSL1 mRNA水平,比色法测定甘油三酯(TG)含量、ATP水平和培养上清FFA浓度变化,生化法测定酮体含量和培养上清葡萄糖浓度变化。结果 FFA的诱导可显著提高ACSL1蛋白表达水平(P<0.01),但对ACSL1 mRNA水平无明显影响(P>0.05),细胞内TG含量显著升高(P<0.01或P<0.05),酮体含量显著升高(P<0.05),培养上清葡萄糖消耗显著增加(P<0.01),胞内ATP水平无明显变化(P>0.05),与0.2 mmol/L、0.4 mmol/L FFA组相比,0.8 mmol/L FFA组培养上清FFA消耗显著增加(P<0.01或P<0.05)。结论 FFA通过上调ACSL1蛋白表达水平致肝细胞TG蓄积。

Objective To investigate the effect of free fatty acids （FFA） on long-chain acyl-CoA synthetase I（ACSL1） expression level and lipid metabolism in L02 cells. Methods The cells were treated by FFA （0.2, 0.4, 0.8 mmol/L） for 48 h. ACSLI mRNA level was measured by quantitative real-time polymerase chain reaction （PCR） and protein level by Western blotting. Cellular triglyceride （TG）, ketone bodies （Ket）, ATP and consumption of FFA and glucose in culture supernatant were measured. Results Compared with normal control group, treatment of L02 cells with FFA did not affect ACSLI mRNA expression level but significantly increased ACSL1 protein expression level. TG content, Ket level and consumption of glucose in culture supernatant were significantly higher and ATP level was not affected. Compared with 0.2 and 0.4 mmol/L FFA group, the consumption of FFA in culture supernatant was significantly higher in treatment with 0.8 mmol/L FFA. Conclusion FFA induced intracellular TG accumulation by up-regulating ACSL1 protein level in L02 cells.