松脂醇二葡萄糖苷激活Wnt/β-catenin信号通路保护成骨细胞

Pinoresinol diglucoside activates the Wnt/beta-catenin signaling pathway to protect osteoblasts

背景:松脂醇二葡萄糖苷可以促进骨形成与骨基质的合成,加速骨组织修复,但其对成骨细胞的影响和作用机制仍需进一步探索。目的:基于Wnt/β-catenin信号通路探讨松脂醇二葡萄糖苷对地塞米松干预成骨细胞的影响和作用机制。方法:设置不同浓度的地塞米松组和松脂醇二葡萄糖苷组对成骨细胞干预24 h,筛选最佳干预浓度;使用地塞米松、松脂醇二葡萄糖苷和Wnt/β-catenin抑制剂XAV-939对成骨细胞进行干预,设置对照组、地塞米松组、抑制剂组、松脂醇二葡萄糖苷组、松脂醇二葡萄糖苷+抑制剂组。CCK-8法检测细胞活性,检测各组细胞碱性磷酸酶和半胱氨酸天冬氨酸蛋白酶3/7酶活性,Annexin V/PI染色与EdU法检测细胞凋亡与增殖情况,Real-Time qPCR检测Wnt3a、β-catenin、c-myc、骨钙素、Ⅰ型胶原蛋白的mRNA表达水平,Western Blot检测Wnt3a、β-catenin、c-myc、骨钙素、Ⅰ型胶原蛋白的蛋白表达水平。结果与结论:①地塞米松和松脂醇二葡萄糖苷干预成骨细胞24 h后,发现浓度为10μmol/L的地塞米松细胞抑制率为实验最佳干预浓度;松脂醇二葡萄糖苷浓度在100μmol/L时,细胞增殖最为明显;②与地塞米松组比较,松脂醇二葡萄糖苷组的碱性磷酸酶活性显著增强(P<0.05),半胱氨酸天冬氨酸蛋白酶3/7酶活性显著降低(P<0.05);Annexin V/PI染色和EdU法细胞增殖检测结果表明,松脂醇二葡萄糖苷可抑制地塞米松干预后成骨细胞的凋亡,促进成骨细胞增殖;③与地塞米松组和抑制剂组比较,松脂醇二葡萄糖苷组和松脂醇二葡萄糖苷+抑制剂组中Wnt3a、β-catenin、c-myc、骨钙素、Ⅰ型胶原蛋白mRNA和蛋白表达水平均显著升高(P<0.05);④结果表明,松脂醇二葡萄糖苷可以抑制地塞米松干预后的成骨细胞凋亡,通过激活Wnt/β-catenin信号通路来保护成骨细胞活性,促进成骨细胞增殖,可能发挥延缓激素性股骨头坏死的作用。

BACKGROUND:Pinoresinol diglucoside promotes bone formation and bone matrix synthesis and accelerates bone tissue repair.However,the mechanism of action and effects of this compound in osteoblasts need to be further explored.OBJECTIVE:To investigate the effect and mechanism of action of pinoresinol diglucoside on dexamethasone-treated osteoblasts based on the Wnt/β-catenin signaling pathway.METHODS:Different concentrations of dexamethasone groups and pinoresinol diglucoside groups were set to treat osteoblasts for 24 hours,and the optimal intervention concentrations were screened.Osteoblasts were treated with dexamethasone,pinoresinol diglucoside and inhibitor XAV-939.Then,control group,dexamethasone group,XVA-939 group,pinoresinol diglucoside group,pinoresinol diglucoside+XVA-939 group were set up.Cell counting kit-8 assay was used to detect cell activity.Alkaline phosphatase activity and caspase3/7 enzyme activity in cells were detected.Annexin V/PI staining and EdU assay were used to detect cell apoptosis and proliferation.Real-time qPCR and western blot were used to detect the mRNA and protein expression levels of Wnt3a,β-catenin,c-myc,osteocalcin,and type I collagen,respectively.RESULTS AND CONCLUSION:After dexamethasone and pinoresinol diglucoside intervened in osteoblasts for 24 hours,10μmol/L dexamethasone was found to be the optimal intervention concentration for cell inhibition,and cell proliferation was most pronounced at a concentration of pinoresinol diglucoside of 100μmol/L.Compared with the dexamethasone group,alkaline phosphatase activity was significantly enhanced(P<0.05)and caspase3/7 enzyme activity was significantly reduced(P<0.05)in the pinoresinol diglucoside group.Annexin V/PI staining and cell proliferation assay by EdU method showed that pinoresinol diglucoside inhibited apoptosis and promoted proliferation of osteoblasts after dexamethasone intervention.The mRNA and protein expression levels of Wnt3a,β-catenin,c-myc,osteocalcin,and type I collagen were significantly higher in the pinoresinol diglucoside group and pinoresinol diglucoside+XVA-939 group compared with the dexamethasone and XVA-939 groups(P<0.05).To conclude,pinoresinol diglucoside can inhibit osteoblast apoptosis after dexamethasone intervention,protect osteoblast activity and promote osteoblast proliferation by activating the Wnt/β-catenin signaling pathway,which may play a role in delaying steroid-induced osteonecrosis of the femoral head.