Effect of compound vibration on bone quality of ovariectomized rats / 中国组织工程研究

ABSTRACT

BACKGROUND: Whole body vibration which is used to prevent and treat osteoporosis recently is uncomfortable due to its strong vibration strength. The designed compound vibration with low vibration strength could effectively prevent bone quality decrease of ovariectomized rats. OBJECTIVE: To verify the effect of compound vibration with low vibration strength on the bone quality of ovariectomized rats. METHODS: A total of 32 4-month-old female SD rats were used in this study. All SD rats were randomly dlvided into 4 groups normal control group, ovadectomized control group, vibration Ⅰ group (45 Hz-55 Hz, 0.05 g-0.1 g), and vibration Ⅱ group (45 Hz-55 Hz, 0.12 g-0.21 g), with8 rats for each group. The intervention to each vibration group was onea day, 20 minutes/tlmes and 5 days per week. The resting interval was shorted than 2 days, and the whole vibration intervention lasted 13 weeks. Bone mineral density (BMD) before and after vibration, ex vivo bone microstructure parameters and biomechanics parameters ware measured in this study. RESULTS AND CONCLUSION: Lumbar BMD of ovariectomized control group was decreased (P < 0.05), but the BMD in the normal control group and the two vibration groups was increased significantly. Femoral BMD of all groups was increased, but there was no significant difference among the four groups. Bone microstructure parameters of the three ovariectomized groups ware decreased; however, parameters including number, thickness and distance of bone trabecula and bone volume fraction in the vibration Ⅱ group were significantly improved compared to ovadactomized control group. Moreover, bone strength of lumbar vertebra in the two vibration groups was significantly increased (P=0.025, 0.006), but there was no significant difference compared to normal control group. Compound vibration with low strength could effectively prevent BMD decrease of ovadectomized rats, lighten the dagrea of bone microstructure damage, keep bone strength, improve bone quality of ovadectomized rats, and potentially prevent osteoporosis.