β-谷甾醇与豆甾醇对非酒精性脂肪肝作用的体外研究

EFFECTS OF β-SITOSTEROL AND STIGMASTEROL ON NON-ALCOHOLIC FATTY LIVER DISEASE IN VITRO

目的通过体外实验研究β-谷甾醇与豆甾醇对非酒精性脂肪肝(NAFLD)发挥预防作用的量效关系。方法利用1.5μmol油酸处理LO2人肝细胞建立NAFLD细胞模型,药物组首先分别用10、20、50μmol/Lβ-谷甾醇或豆甾醇孵育细胞,之后用1.5μmol油酸处理LO2人肝细胞;实验检测细胞活力、甘油三酯(TG)、丙二醛(MDA)和谷胱甘肽(GSH)水平,并观察细胞形态的变化。结果总体上,β-谷甾醇或豆甾醇可显著降低脂肪肝细胞TG含量及脂质过氧化物MDA水平,提高抗氧化剂GSH含量,其中20μmol/L豆甾醇处理后细胞TG、MDA分别较模型组降低了66.6%和81.7%,而GSH含量增加了73.6%;10μmol/L和50μmol/Lβ-谷甾醇处理后,TG含量均比模型组低55.6%,MDA含量则分别降低了59.3%和62.9%,GSH含量分别增加了77.4%和72.6%。此外,两种植物甾醇对肝细胞增殖的抑制作用均随浓度升高而增强,但相同浓度豆甾醇对细胞活力的影响明显弱于β-谷甾醇。结论豆甾醇与β-谷甾醇可改善NAFLD肝细胞脂肪变性程度,减轻氧化应激反应,但作用效果呈不同量效关系。

Objective To explore the preventive effects of β-sitosterol and stigmasterol on non-alcoholic fatty liver disease in vitro. Methods LO2 liver cells were treated with oleic acid （1.5 μmol/L） to establish the non-alcoholic fatty liver disease （NAFLD） cell model. The experimental groups were treated with different concentrations （10, 20, 50μmol/L） of β-sitosterol or stigmasterol, respectively, and followed by oleic acid treatment. The cell vitality and the levels of triglyceride （TG）, malondialdehyde （MDA） and glutathione （GSH） were measured. The changes of cell morphology were observed. Results Compared with the model group, β-sitosterol and stigmasterol significantly decreased the levels of TG and MDA and increased the content of antioxidant GSH in experimental groups. In the experimental group treated with 20 μmol/L stigmasterol the content of TG and MDA were reduced by 66.6% and 81.7%, respectively, while GSH level was increased by 73.6%. After treatment with β-sitosterol （10 or 50 μmol/L）, TG level were reduced by 55.6%, and MDA level was reduced by 59.3% and 62.9%, while GSH was increased by 77.4% and 72.6%, respectively compared with model group. In addition, the inhibition of phytosterols on the proliferation of liver cell was enhanced with the increasing of concentrations, but the effect of stigmasterol on cell vitality was weaker than that of β-sitosterol at the same concentration. Conclusion Stigmasterol and β-sitosterol could effectively improve the situation of NAFLD through relieving steatosis and oxidative stress in different dose-effect manners.