姜黄素对大鼠肾系膜细胞结缔组织生长因子表达的影响

Effect of Curcumin on the Expression of Connective Tissue Growth Factor in Rat Glomerular Mesangial Cells

目的观察姜黄素对大鼠肾小球系膜细胞结缔组织生长因子(CTGF)表达的影响,并探讨其可能的影响机制。方法体外培养大鼠肾系膜细胞,同步后用血清刺激,并用不同浓度的姜黄素、姜黄素联合mTOR特异阻断剂雷帕霉素、姜黄素和磷脂酰肌醇3激酶/蛋白激酶B(PI3K/Akt)特异抑制剂LY294002进行干预处理。采用RT-PCR检测CTGF和纤维连接蛋白(Fn)mRNA表达;Western blot检测CTGF蛋白和磷酸化蛋白激酶B(p-Akt)表达。结果①血清刺激系膜细胞6 h,姜黄素浓度依赖性抑制CTGF和Fn mRNA的表达;姜黄素联合雷帕霉素对CTGF和Fn mRNA表达的抑制作用较单用同浓度姜黄素明显;LY294002预处理后,姜黄素对CTGF和Fn mRNA表达的抑制作用较未预处理组减弱。②25μmol/L姜黄素作用细胞301、20 min,p-Akt蛋白表达较同时间点血清对照组明显减弱;且LY294002预处理后姜黄素对p-Akt表达的抑制作用较未预处理组亦明显减弱。③血清刺激系膜细胞24 h,姜黄素对CTGF蛋白的表达亦起抑制作用;姜黄素联合雷帕霉素对CTGF蛋白表达抑制更明显;LY294002预处理后,姜黄素对CTGF蛋白表达的抑制效果较未预处理组减弱。结论姜黄素可抑制血清刺激的肾小球系膜细胞CTGF的表达,其机制可能与PI3K/Akt信号途径和mTOR信号途径有关。

Objective To investigate the effect of curcumin on the expression of connective tissue growth factor （CTGF） in rat glomerular mesangial cells and the potential mechanisms. Methods Growth arrested and synchronized rat mesangial cells were stimulated by serum. The mesangial cells were pretreated with curcumin, curcumin combined with rapamycin, or curcumin combined with P13K/Akt specific inhibitor LY294002. The expression of CTGF and fibronectin （Fn） mRNA in mesangial cells was detected by semi-quantitative RT-PCR. and that of CTGF protein and phospho-Akt protein by Western blot. Results After the cells were exposed to bovine calf serum for 6 h. curcumin could down-regulate the mRNA expression of CTGF and Fn in a dose dependent manner as compared with the control group. Curcumin combined with rapamycin could down-regulate the mRNA expression of CTGF and Fn more obviously than curcumin alone with the same concentration. After the cells Were pretreated with LY294002. the inhibitory effects of curcumin on the expression of CTGF and Fn mRNA were weakened. After the cells were treated with 25 μmol/L curcumin for 30 and 120 min. the expression of p-Akt protein was decreased as compared with the control group at the same time, and the inhibitory effects of eurcumin were also weakened by LY294002 pre-treatmerit. After the cells were exposed to bovine calf serum for 24 h. the protein expression of CTGF in curcumin treatment group was reduced as compared with the control group, and in curcumin combined with rapamycin group, the expression of CTGF protein was inhibited more markedly. After the cells were pretreated with LY294002. the phospho-Akt protein expression was detected, and curcumin down-regulated the CTGF protein expression more weakly than in no-LY294002 pretreatment group. Conclusion Curcumin can inhibit the expression of CTGF in serum-induced glomerular mesangial cells, which might be related to P13K/Akt signal pathway and mammal target of rapamycin signal pathway.