RNA干扰PDCD4基因表达对巨噬细胞脂质沉积的影响

Effect of PDCD4 siRNA on the lipid accumulation in macrophages

目的探讨程序性细胞死亡4(PDCD4)对巨噬细胞脂质沉积的影响及机制。方法实验分为PDCD4 siRNA组和阴性对照siRNA组。用PDCD4 siRNA和阴性对照siRNA干扰小鼠腹腔巨噬细胞中PDCD4的表达,RT-PCR法和Western blotting法检测干扰效率;经ox-LDL刺激后,油红O染色检测巨噬细胞内油脂含量变化;Real-Time PCR法检测胆固醇流出相关基因肝X受体α(LXR-α)、三磷酸腺苷结合盒转运体A1(ABCA1)及三磷酸腺苷结合盒转运体G1(ABCG1)表达的变化。结果 PDCD4 siRNA可有效降低巨噬细胞中PDCD4的mRNA及蛋白表达水平。与阴性对照siRNA组相比,PDCD4 siRNA组巨噬细胞内油脂含量明显减少(P<0.001),并且显著上调细胞内LXR-α(P<0.05)、ABCA1(P<0.01)及ABCG1(P<0.001)的表达。结论可通过促进胆固醇流出而减少巨噬细胞内的脂质沉积干扰PDCD4基因表达。

Objective To investigate the effect of PDCD4 on lipid accumulation in macrophages.Methods The cells were divided into PDCD4 siRNA group and negative control siRNA group.Gene silencing was performed in murine macrophages using PDCD4 siRNA and negative control siRNA;the mRNA and protein levels of PDCD4 were detected by RT-PCR and Western blotting;after treatment with ox-LDL, the lipid contents in macrophages were detected by Oil red O staining;the expressions of cholesterol efflux-related genes liver X receptor α（ LXR-α） , ATP-binding cassette transporter A1 （ ABCA1 ） and ATP-binding cassette transporter G1 （ ABCG1 ） were detected by Real-Time PCR. Results PDCD4 siRNA effectively reduced the expression of PDCD4 on both mRNA and protein levels in macropha-ges;the lipid contents decreased significantly in PDCD4 siRNA group compared with those in negative control siRNA group （P＆lt;0.001）, and the expressions of LXR-α（P＆lt;0.05）, ABCA1 （P＆lt;0.01） and ABCG1 （P＆lt;0.001） were markedly up-regulated.Conclusion Silencing of PDCD4 gene can reduce the lipid accumulation in macrophages through promoting cholesterol efflux.