小鼠生长期下坡跑改善去卵巢后骨中Ⅰ型胶原蛋白表达和骨形成

Effects of Downhill Running in Growth Period on Expression of TypeⅠCollagen and Bone Formation in Ovariectomized Mice

目的:研究下坡跑对生长期和去卵巢小鼠骨中Ⅰ型胶原蛋白表达和骨量的影响。方法:80只4周龄C57BL/6雌性小鼠适应性喂养1周后随机分为安静组(C组)、运动组(D组)、安静去卵巢组(C+OVX组)、运动去卵巢组(D+OVX组)和安静假手术组(C+SHAM组),每组16只。D组和D+OVX组进行8周下坡跑训练,剩余3组不训练。最后1次训练结束24 h后,处死C组和D组小鼠;C+OVX组和D+OVX组小鼠进行去卵巢手术,C+SHAM组进行假手术,术后安静状态下喂养6周,静养结束后,处死这3组小鼠。结果:(1)8周下坡跑训练结束后,小鼠骨中COL1α1 mRNA和Ⅰ型胶原蛋白表达上调有统计学意义,骨组织形态计量学指标和骨量增加有统计学意义;(2)去卵巢6周后,小鼠骨中COL1α1 mRNA和Ⅰ型胶原蛋白表达上调有统计学意义,骨组织形态计量学指标和骨量提高有统计学意义。结论:下坡跑可能通过上调骨中COL1α1 mRNA和Ⅰ型胶原蛋白表达来改善骨组织形态结构和骨量,且这种作用在去卵巢后仍然存在。

Objective： The purpose of this study was to research the effect of downhill running on expression of type I collagen and bone mass in growth and ovariectomized mice. Methods： 80 four-week-old C57BL/6 female mice were randomly divided into 5 groups as control group （C）, downhill running group （D）, ovariectomized control group （C＋OVX）, ovariectomized exercise group （D＋OVX） and control sedentary group （C＋SHAM）. D Group and D＋ OVX group were forced to downhill running for eight weeks while the residual groups received no training. C and D group mice were sacrificed after the 8 week training program; C＋OVX and D＋OVX group mice were subjected to ovariectomy 24 h after the last training and C＋SHAM group mice reveived a sham parallel. Then C＋OVX, D＋OVX and C＋SHAM group mice were killed 6 week later. Results： （1）After 8 weeks training, the expression of COLlcdmRNA and type I collagen in bone were significantly upregulated, the indexs of bone histomorphometry and bone mass were significantly increased; （2） After 6 weeks, the COL1α1 mRNA and type I collagen were remain significantly upregulated, the index of bone histomorphometry and bone mass were remain significantly increased. Conclusions： Downhill running can increase the trabecular structure of cancellous and bone mass by upregulating the expression of COL1α1 mRNA and type I collagen in bone and also this effect can extend at least six weeks in ovariectomized mice.