糖肾方激活PGC-1α/LXR/ABCA1信号通路改善高脂诱导的巨噬细胞胆固醇摄取及流出

目的：观察中药糖肾方对棕榈酸钠诱导的RAW264.7巨噬细胞的脂质流出、摄取等转运相关分子的影响。方法：用棕榈酸钠（PA）诱导RAW264.7巨噬细胞制造高脂环境，经MTT测定后给予不同浓度糖肾方及PGC-1α-siRNA干预；利用Western blot和Real-time PCR检测细胞过氧化物酶体增殖激活受体γ共激活因子1α（PGC-1α）、肝脏X受体（LXR）、ATP-结合盒转运蛋白（ABCA1）、分化簇36（CD36）的表达；Filipin染色及BODIPY 493/503染色观察糖肾方对细胞内脂滴沉积的影响。结果：Western blot及Real-time PCR的结果提示PA组PGC-1α、LXR、ABCA1表达减少，CD36表达增加（P<0.05），给予糖肾方干预可上调PGC-1α、LXR、ABCA1的表达，下调CD36的表达（P<0.05）；Filipin染色及BODIPY 493/503染色结果显示糖肾方可改善高脂状态下细胞内脂滴沉积的情况。PGC-1α-siRNA干预可抑制糖肾方上调PGC-1α、LXR、ABCA1表达以及抑制CD36的表达的作用。 结论：糖肾方可激活PGC-1α/LXR/ABCA1信号通路促进脂质流出、下调CD36的表达抑制脂质摄取，改善因脂质代谢异常引起的相关疾病等。

Tangshen formula improves cholesterol uptake and efflux of macrophages induced by high lipid via activating PGC-1α/LXR/ABCA1 pathway

AIM: To observe the effects of Tangshen formula (TSF) treatment on lipid efflux and uptake in sodium palmitate (PA) induced RAW264.7 macrophages. METHODS: After 200 μmol/L PA induced RAW264.7 macrophages, TSF and PGC-1α-siRNA were given to intervene respectively. The lipid content in the cells was detected by ELISA kit; intracellular lipid droplet deposition was detected by BODIPY 493/503 and Filipin staining. Western blot and Real-time PCR were used to detect the expression of PGC-1α, LXR, ABCA1 and CD36. RESULTS: TSF diminished the levels of TC, TG and intracellular lipid droplet deposition in PA-induced RAW264.7 macrophages. Western blot and Real-time PCR analysis showed that TSF could up-regulate the expression of PGC-1α, LXR, ABCA1 and down-regulate the expression of CD36. Furthermore, silencing PCG-1α by SiRNA significantly suppressed the effects of upregulating the expression of PGC-1α, LXR and ABCA1, and downregulating the CD36 expression with TSF treatment. CONCLUSION: TSF may extenuate intracellular lipid droplet deposition in macrophages by upregulating cholesterol efflux through activating the PGC-1α/LXR/ABCA1 pathway and inhibiting lipid uptake through down-regulateing the expression of CD36.