高密度脂蛋白对炎症状态下脂肪细胞功能的保护作用

Effect of high-density lipoprotein on adipocytes stimulated by lipopolysaccharide

目的探讨高密度脂蛋白(high-density lipoprotein,HDL)对炎症状态下脂肪细胞胆固醇流出的保护作用。方法将3T3-L1前脂肪细胞诱导分化成为成熟的脂肪细胞,用不同浓度的HDL(10~100mg·L-1)孵育16h,然后加入脂多糖(lipopolysaccharide,LPS,100μg·L-1)共同孵育6h,收集细胞上清测定白介素-8(interleukin-8,IL-8)的浓度,并检测不同浓度的HDL对LPS刺激的脂肪细胞胆固醇流出的影响。结果LPS刺激脂肪细胞使得IL-8的分泌增多(P【0.05),HDL能降低细胞上清中IL-8的含量(P【0.05),并呈浓度依赖性;LPS刺激脂肪细胞使得胆固醇的流出明显减少(P【0.05),在炎症状态下HDL呈浓度依赖性的促进脂肪细胞胆固醇的流出(P【0.05)。结论HDL能够降低炎性脂肪细胞分泌的趋化因子IL-8的水平,并能促进细胞内胆固醇的流出。

Aim To explore the protective effect of high-density lipoprotein (HDL) on adipocytes stimulated by lipopolysaccharide (LPS). Methods 3T3-L1 preadipocyte was used to differentiate adipocytes in cell cultures. Adipocytes were cultured with various concentrations of HDL adding or not adding LPS. We measured IL-8 release in the medium by using the IL-8 ELISA kit. Cholesterol efflux rate was determined through measuring the release of radioactivity from 3H-cholesterol prelabeled cells into medium containing HDL in LPS induced adipocytes.Results The secretion of IL-8 in adipocytes treated with LPS was found to be higher than the baseline. HDL (10 to 100 mg·L-1) significantly decreased (P<0.05 ) LPS-induced IL-8 secretion by adipocytes in a concentration-dependent manner. LPS reduced cholesterol efflux from adipocytes. HDL significantly enhanced the cholesterol efflux in LPS treated adipocytes in a dose-dependent manner.Conclusion Adipocytes stimulated by LPS can produce IL-8 and HDL can enhance LPS-mediated injury in adipocytes. HDL can promote cholesterol efflux in adipocytes stimulated by LPS.