ABSTRACT
Objective To investigate the effects of different interventions on the biomechanic indexes in femur bones of ovariectomized rats with osteoporosis.Methods Eighty healthy female Sprague-Dawley rats,aged 3 months,were randomly divided into an ovariectornized(OVX,n=68)group and a sham-operation(Sham,n=12)group.At the 11th week after the operation,the OVX group was further randomly divided into a control group(n=11),an estradiol group(E2,n=10),a genisteine group(G,n=10),a treadmill exercise group(TE,n=10),a lithium chloride group(LiCl,n=10)and a whole-body vertical vibration group (WBVV,n=10).Then the rats began to receive different interventions as their group names implied.At the end of 8 weeks,their right femurs were isolated and the biomechanic parameters were detected using the three point bending test.Results (1)Both the maximum load and elastic load in E2,G,TE,WBVV and LiC1 groups were significantly higher than that of the control group,while no significant differences were seen in maximum deflection and elastic deflection.(2)The elastic stress,maximum strain,and elasticity modulus in E2,G,and WBVV groups were significantly higher than that of the control group,while no significant differences were seen in maximum stress and elastic strain among them.The maximum stress,elastic stress,maximum strain,and elasticity modulus in TE group were significantly higher than the control group while no significant differences were seen in the elastic strain.The maximum stress,elastic stress,and elasticity modulus in LiC1 group were significantly higher than the control group,but no significant differences were seen in maximum strain and elastic strain between them.Conclusion E2,genistein,treadmill exercise,whole-body vertical vibration,and LiC1 have quite similar effects on structural mechanics indexes of femurs in OVX rats with osteoporosis,but they have different impacts on the material mechanics indexes.
ABSTRACT
Objective The aim of this study was to observe the effects of whole-body vertical vibration, treadmill exercise, genistein administration and estrogen injection on the uterus weight index and uterus histology as well as the ex-pression of glycogen synthase kinase ( GSK-3β) protein in the uterus of ovariectomized osteoporotic rats.Methods Sev-enty-two healthy 3-month old female SD rats were randomly divided into two groups by body weight:sham-operation group (Sham) and ovariectomized group (OVX).At 10 weeks after OVX operation, the OVX rats were randomly divided into the following five groups by body weight: OVX group, whole-body vertical vibration group (WBVV), treadmill exercise group ( TX) , genistein group ( G) and 17β-estrogen group ( E2 ) .Then they were treated with different methods according to the experiment design.At the end of experiment, the uterus weight was measured with an electronic balance.The uterus histology was observed with HE staining and the expressions of GSK-3βand P-GSK-3βproteins were detected by Western blot.Results Apart from E2 treatment, all the other three treatments did not increase the uterus weight and the thickness of endometrium compared with that in the OVX rats.Apart from genistein treatment, all the other three treatments increased the ratio of protein expression of P-GSK-3βto GSK-3βcompared with that in the OVX rats.Conclusions Both whole-body vertical vibration and treadmill exercise can stimulate the phosphorylation of GSK-3βin the uterus of OVX osteoporotic rats.However, genistein has no such stimulation effect.