乙醇致氧化应激损伤和HBV复制对肝癌系细胞蛋白酶体活性的影响

Effect of Ethanol-induced Oxidative Stress and HBV Replication Activity on Proteasome of Hepatoma Cells

目的研究乙醇致氧化应激损伤和HBV复制,对肝癌系细胞蛋白酶体活性的影响。方法分别用1.5%、3%、5%、8%体积分数的乙醇作用于HepG2和HepG2.2.15细胞16h后收集上清检测天门冬氨酸氨基转移酶(aspartate aminotransferase,AST)、四甲基偶氮唑盐比色法(methye thiazolye telrazlium,MTT)检测细胞活性,计算抑制率。两种细胞经1.5%、5%乙醇处理16h后用WesternBlot检测免疫蛋白酶体亚基低分子量多肽蛋白2(low molecular weight polypeptide protein 2,LMP2)的表达。结果HepG2.2.15细胞对3%、5%的乙醇诱导损伤更敏感。HepG2.2.15细胞的LMP2表达比HepG2细胞低,1.5%乙醇处理16h以后,HepG2.2.15细胞的蛋白酶体亚基LMP2表达比HepG2细胞下调更明显。结论乙醇和HBV复制,下调肝癌细胞蛋白酶体亚基LMP2的表达。

Objective To study the effect of ethanol-induced oxidative stress and HBV replication on proteasome activity of hepatoma cells. Methods HepG2 and HepG 2. 2. 15 cells were stimulated with ethanol at gradient concentrations of 1.5%, 3%, 5%and 8% respectively for 16 hours. The supernatants were harvested for aspartate aminotransferase （AST） assessment, and the cell activity was determined by methye thiazolye telrazlium （MTT） with growth inhibition rate of the two types of cells calculated. The expression of immunoproteasome subunit low molecular weight polypeptide protein 2 （LMP2） was detected by Western blotting. Results HepG 2. 2. 15 cells were more sensitive to 3% and 5 % ethanol induction than HepG2 cells. The expressions of LMP2 were much lower in HepG 2. 2. 15 cells than in HepG2 cells with or without 1.5% ethanol exposure. Conclusion Ethanol and HBV down-regulate the expression of immunoproteasome subunit LMP2 in hepatoma cells.