Aim To investigate the regulation of de-hydroepiandrosterone ( DHEA ) for osteoprotegrin (OPG) and receptor activator of nuclear factor kappa-B ligand ( RANKL) via estrogen receptor beta( ER(3). Methods hMG63-ERβ group (infected with pWPT-ERβ), hMG63-shERβ group (infected with pLVTHM-GFP/ERβ-shRNA) and hMG63 group (control) were cultured and treated with 10-7 mol ? L-1 DHEA, with or without U0126. The expression of OPG, RANKL, pERKl/2, JNK and p38 in hMG63 was evaluated by ELISA and Western blot, respectively. Results The expression of OPG increased by the time of DHEA culture (P <0. 01) , while there was no obvious change in RANKL expression. Compared with hMG63 cells, ERain hMG63-shERβ and hMG63-ERp group showed no significant change under the effect of DHEA. When the level of ERβ was high, DHEA could accelerate the expression of OPG and pERKl/2( P <0. 05 ,P <0. 01), which was blocked partly by U0126. In contrast, ERβ expression in hMG63-shERβ group was decreased in accordance with the decrease of pERKl/2 and OPG. Conclusion DHEA selectively acts on osteoblasts via the dominant receptor of ERβ, which mediates the pERKl/2-MAPK signal pathway for up-regulation of OPG instead of RANKL.%目的 探讨β雌激素受体( ERβ)介导脱氢表雄酮(DHEA)对成骨细胞骨保护素/细胞核因子κB受体活化因子配体(OPG/RANKL)的调节作用.方法 构建ERβ沉默表达( pLVTHM-GFP/ERβ-shRNA)和ERβ高表达(pWPT-ERβ)重组质粒,并转染人成骨细胞系hMG63,使hMG63的ERβ沉默表达(hMG63-shERβ)和高表达(hMG63-ERβ).有或无U0126(丝裂原活化蛋白激酶信号途径中特异抑制分子)作用后,给予生理浓度(10-7 mol· L-1)的DHEA作用24、48和72 h,ELISA和Western blot法分别检测hMG63培养上清中OPG和细胞中RANKL蛋白表达；Western blot法检测丝裂原活化蛋白激酶( MAPK)信号途径中pERK1/2、JNK和p38分子的表达.结果 给予DHEA作用48和72 h后,hMG63分泌的OPG明显增高(P＜0.01),而RANKL表达无明显变化；与hMG63细胞相比较,在DHEA作用下hMG63-shERβ和hMG63-ERβ组的ERα表达无明显改变；而hMG63-ERβ细胞中ERβ表达增高,伴随着pERK1/2和OPG的升高(P＜0.05,P＜0.01)；相反,hMG63-shERβ组ERβ表达减少并伴随pERK1/2和OPG分泌的降低(P＜0.05).另外,DHEA对pERK1/2和OPG的升调节可部分被U0126阻断.结论 ERβ可能通过激活pERK1/2-MAPK途径介导了DHEA对成骨细胞OPG/RANKL的调节.
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