胰岛素对THP-1细胞脂蛋白脂酶 mRNA表达及细胞泡沫化的影响

目的 观察胰岛素在氧化低密度脂蛋白(ox-LDL)致人髓系白血病单核细胞株THP-1细胞泡沫化过程中的作用,并探讨其机理.方法 用不同浓度胰岛素及ox-LDL与THP-1细胞一起共同孵育,观察THP-1细胞脂蛋白脂酶(LPL) mRNA RT-PCR产物、非特异性脂酶染色THP-1细胞所得脂酶阳性细胞数、细胞大小变化、油红O染色所得含脂滴细胞数、细胞内胆固醇含量.结果 100 mU/L以上浓度胰岛素各组THP-1细胞LPL mRNA表达与ox-LDL对照组比较上调2倍;细胞周长、脂滴阳性细胞百分率及细胞内胆固醇含量均明显高于ox-LDL对照组(P＜0.05).结论 高浓度胰岛素在ox-LDL存在条件下有促进THP-1细胞向泡沫细胞转化的作用,其机理可能与细胞LPL mRNA表达上调有关.

Insulin induced LPL mRNA expression in THP-1 macrophage and acceleration of transferring the macrophage to foam cell

AIM: To investigate the effect of insulin on ox-LDL transferring the THP-1 cells to foam cells and influencing the LPL mRNA expression in THP-1 cells. METHODS: THP-1 cells were incubated with 50 mg/L ox-LDL and insulin at concentrations of 10 mU/L,100 mU/L,1 000 mU/L and 10 000 mU/L, respectively. The expression of LPL mRNA in cells was detected by RT-PCR. Lipoprotein lipase of THP-1 cells was presented by no-specific lipase staining. THP-1 cells were stained with oil red O. Accumulation of total cholesterol (TC) in THP-1 cells was determined with oxidase assay. RESULTS: In 100 mU/L?1 000 mU/L?10 000 mU/L insulin groups, LPL mRNA expression increased 2 times, the average cell perilength was longer, the percentage of positive oil red O staining cells was significant higher, the content of cholesterol in THP-1 cells was higher than in ox-LDL control ( P< 0.05). CONCLUSION: Insulin accelerates transferring of THP-1 cells to foam cell with exposed to ox-LDL because LPL mRNA expression increased in the cells.