运动和药物联合干预对老年2型糖尿病大鼠骨密度和骨生物力学的影响

Effects on Bone Density and Bone Biomechanic by Movement and Drug in Type 2 Diabetic Old Rats

目的:探讨有氧运动联合药物干预对糖尿病大鼠骨密度和骨生物力学的影响。方法:将15月龄雌性SD大鼠(55只),随机分为正常饮食对照组(NC,11只)和高脂饮食组(HFD,44只),NC组用普通饲料喂养,高脂组给以高脂饲料喂养。8周后除NC组外,其余各组腹腔注射小剂量链脲佐菌素,建立2型糖尿病动物模型,并将其平均分成糖尿病对照组(DC)、糖尿病运动组(DE)、糖尿病药物组(DD)和糖尿病药物运动组(DDE)。DE组和DDE组进行8周的游泳训练,DD组和DDE组按体重灌胃8周二甲双胍。各组大鼠禁食12h,两个运动组大鼠末次运动结束24 h后取材,分离大鼠双侧股骨,剔净周围肌肉和软组织。双能X线法(DXA)测定右侧股骨骨密度,并对左侧股骨进行骨生物力学试验。结果:与NC组相比,DC组股骨重量有降低趋势,没有显著性差异;DE组、DD组及DDE组与DC组相比,股骨重量有升高趋势,但没有显著性差异。与NC组相比,DC组骨密度、骨生物力学指标显著降低(P<0.05);游泳8周后,DE组、DD组及DDE组与DC组相比骨密度及骨生物力学指标中最大应力、最大载荷显著升高(P<0.05),DDE组与DE组相比,骨生物力学指标中最大应力、最大载荷和弹性模量显著性增强(P<0.05)。结论:有氧运动训练和药物两种治疗方式,均改善2型糖尿病大鼠骨密度和骨生物力学指标,从而改变其骨质疏松状态,其中运动联合药物组作用效果更好。

Objective： To investigate the aerobic endurance and drug effects on bone mineral density and bone biomechanics of diabetic rat. Methods： 15-months old male SD rats（ 55） were randomly divided into two groups： normal diet control group（ NC,11） and high fat diet group（ HFD,44）. HFD group was equally divided into diabetic control group（ DC）,diabetic exercise group（ DE）,diabetic drug group（ DD） and exercise group（ DDE） diabetic drugs. NC group was fed with normal diet and the other groups were fed with high fat and high glucose diet. After 8 weeks,groups except NC group were injection by streptozotocin to create diabetic model. DE and DDE group were designed to the swimming training for 8weeks,and these two groups were gavaged by met form in upon weight for 8 weeks. Rats in each group were nest in 12 hours,and then isolated bilateral femur,tick the net around the muscle and soft tissue. Determination of right femur bone mineral density by using dual-energy X-ray（ DXA）,and bone biomechanical of the left femur was measured. Results：compared with NC group,DC group of fresh femoral weight tended to be reduced,and no significant difference. Compared with DC group,the fresh femoral weight was increased in the DE group,DD group and DDE group,however,there were not significant difference. Compared with NC group,bone mineral density and bone biomechanics indexes were decreased significantly（ P〈0.05） in DC group. After swimming for 8weeks,compared with the DC group,bone mineral density and the maximum stress and maximum load of bone biomechanical indexes were significantly increased（ P〈0.05） in DE group,DD group and DDE group. Compared with DE group,the maximum stress,maximum load and elastic modulus of bone biomechanical indexes were obviously increased of DDE group（ P〈0.05）. Conclusion： aerobic exercise training and drug intervention can both improve bone mineral density and bone biomechanical indexes in type 2 diabetic rats,so as to change the osteoporosis. And the movement combined with drug group performs a better effect.