利拉鲁肽对失重大鼠骨质疏松及骨髓间充质干细胞成骨细胞分化的影响

Effects of liraglutide on osteoporosis and differentiation of bone marrow mesenchymal stem cells into osteoblasts in rats

目的:探讨利拉鲁肽对失重大鼠骨髓间充质干细胞(BMSCs)成骨分化的影响,为航天员飞行后骨量丢失的缓解提供实验依据。方法:取30只12周龄SD雄性大鼠,应用随机数字表法分为对照组、失重组、失重+利拉鲁肽组,每组10只。采用尾悬吊28 d的方法构建大鼠失重模型,失重+利拉鲁肽组悬吊2 d后开始给予利拉鲁肽200μg/(kg·d),1次/d,每周6 d,连续4周。于最后一次给药1 d后应用Micro-CT观察大鼠股骨骨量、骨小梁变化。同时,分离对照组及失重组大鼠BMSCs,给予不同浓度利拉鲁肽(1、10或100 nmol/L)刺激21 d,茜素红染色验证BMSCs分化及矿化情况;刺激15 d后通过qRT-PCR和Western blot检测BMSCs中Runx-2、Osterix mRNA及蛋白的表达。结果:Micro-CT结果显示,利拉鲁肽能够显著提高失重大鼠骨体积/组织体积、骨小梁数量以及骨小梁的厚度(P<0.05),促进骨形成。茜素红染色、qRT-PCR和Western blot结果显示,利拉鲁肽能够促进BMSCs向成骨细胞分化且与药物浓度呈正相关。结论:利拉鲁肽能够促进BMSCs向成骨细胞分化,改善由于失重导致的骨质疏松,促进骨形成。

Aim:To investigate the effects of liraglutide on the differentiation of bone marrow mesenchymal stem cells(BMSCs)into osteoblasts,which will be used as experimental basis for alleviation of bone loss in astronauts after flight.Methods:Thirty male SD rats aged 12 weeks were randomly allocated into control group,agravity group,agravity+liraglutide group,with 10 rats in each group.The agravity model was established by the 28-day-hindlimb-unloading.The rats in the agravity+liraglutide group were given liraglutide[200μg/(kg·d)]once a day for 6 days a week for 4 weeks after 2 days of hindlimb-unloading.The changes of bone mass and trabecular bone in the rats were observed by micro-CT the day after the last treatment.At the same time,BMSCs were isolated from control and agravity rats,and stimulated with different concentrations of liraglutide(1,10,100 nmol/L).After 21 days,the differentiation and mineralization of BMSCs were investigated by alizarin red staining.Meanwhile,qRT-PCR and Western blot were used to determine the mRNA and protein expressions of Runx-2 and Osterix.Results:Micro-CT results showed that liraglutide could significantly improve bone volume/tissue volume,the number of trabeculae and the thickness of trabeculae(P<0.05),and promote bone formation.The results of alizarin red staining,qRT-PCR and Western blot showed that liraglutide could promote BMSCs to differentiate into osteoblasts and the efficacy was positively correlated with drug concentration.Conclusion:Liraglutide can promote the differentiation of BMSCs into osteoblasts,improve the osteoporosis caused by agravity,and promote bone formation.