不同运动对生长期大鼠Wnt/β-catenin信号及软骨内成骨的影响

Effects of Different Exercises on Wnt/β-catenin Signal and Endochondral Osteogenesis in Growing Rats

目的:探索不同运动方式对生长期大鼠Wnt/β-catenin信号通路相关分子表达及软骨内成骨的影响。方法:对生长期大鼠进行6周的不同方式的运动,利用三点弯曲测骨强度,Micro-CT对股骨微结构进行检测,利用RT-PCR、west-bloting检测细胞因子mRNA和蛋白表达。结果:与C组相比,D组胫骨、股骨围度湿重有非常显著性增加(P<0.01),且D组围度较R组有显著性增加(P<0.05),骨强度测试D组有非常显著性增加(P<0.01);CT检测发现,股骨皮质骨BMD只有D组有显著性增加(P<0.05);Wnt4mRNA的表达,R组有显著性上调(P<0.05),D组有非常显著性上调(P<0.01);Wnt8mRNA、Wnt9mRNA的表达,R组和D组有非常显著性上调(P<0.01);GSK3βmRNA的表达,只有D组有显著性上调(P<0.05);β-cateninmRNA的表,R组和D组都有非常显著性上调(P<0.01),与R组相比,D组也有显著性上调(P<0.05);Runx2mRNA的表达,R组有显著性上调(P<0.05),D组的有非常显著性上调(P<0.01);Wnt8蛋白表达,R组和D组都有非常显著性增加(P<0.01),D组较R组也有非常显著性增加(P<0.01);β-catenin、Runx2蛋白表达,R组有显著性增加(P<0.05),D组有非常显著性增加(P<0.01),其中D组Runx2较R组也有显著性增加(P<0.05)。结论:跳跃运动通过Wnt/β-catenin信号通路,促进生长期大鼠生长板软骨内成骨,提高骨健康水平。

Objective:To explore the effects of different exercise modes on the expression of Wnt/β-catenin signaling pathway-related molecules and endochondral osteogenesis in growing rats. Methods:Growing rats were exercised in different ways for 6 weeks. Bone strength was measured by three-point bending,femoral micro-structure was detected by micro-CT,and cytokine gene and protein expression were detected by RT-PCR and western-bloting. Results:Compared with group C,the wet weight of tibia and femur circumference in group D increased significantly(P<0.01),and group D increased significantly(P<0.05). Bone strength test showed a significant increase in group D(P<0.01). CT examination showed that BMD of femoral cortical bone increased significantly only in group D(P<0.05).Wnt4 mRNA expression was significantly up-regulated in R group(P<0.05),and significantly up-regulated in D group(P<0.01);Wnt8 and Wnt9 mRNA expression was significantly up-regulated in R group and D group(P<0.01),while GSK3β expression was significantly up-regulated in D group(P<0.05);the expression of β-catenin mRNA was significantly up-regulated in R group and D group(P<0.01),compared with R group,D group also significantly up-regulated(P<0.05);the expression of Runx2 gene was up-regulated significantly in R group(P<0.05),and very significantly in D group(P<0.01). Wnt8 protein expression in R group and D group increased significantly(P<0.01),and that in D group was also significantly higher than that in R group(P<0.01);the expression of β-catenin and Runx2 protein in R group was significantly higher(P<0.05),and that in D group was significantly highe(rP<0.01),and Runx2 protein expression in D group was also significantly higher than that in R group(P<0.05). Conclusions:Jumping exercise can promote endochondral osteogenesis of growth plate and improve bone health through Wnt/β-catenin signaling pathway in growing rats.