| Objective: To research the pharmacology effect of a new phytoestrogen a-zeranol (a-ZAL) on osteoporotic bone fracture healing and bone micro-environment, for the clinical application based on experiment and theory.Methods: (1) animal model: sixty eight 6-month-old female SD (Sprague-Dawley) rats were randomly divided into 2 groups: control group(18) and operation group(50), the control group had sham operation, the operation group had oophorectomy, 3 months post operation ,10 rats of each group were randomly selected to have bone density examination which determine the success of the osteoporotic bone animal model. Then, the remaining 48 rats were having tibial fracture surgery to establish osteoporotic bone fracture group (OPFM 40) and general fracture group (CFM 8), then the OPFM group was randomly divided into 5 groups, each group had 8 rats respectively:①operation model group (OVX group): administered with equal amount of solvent feed;②estrogen group (OVX + E group): administered with conjugated estrogen;③high dosed zeranol group (OVX + HZ group): administered with high doses of a-ZAL ;④zeranol in the dose group (OVX + MZ group): administered with moderate doses of a-ZAL;⑤zeranol low dose group (OVX + LZ group): administered with low doses of a-ZAL.CFM group was administered with equal solvent feed .all groups were given orally at the same time every 3 days for 5 weeks. (2) Detection index:①X ray: X-ray to examine the situation of fracture healing;②Index of osteoblast activity: ELISA was used to detect serum osteocalcin (BGP) and bone alkaline phosphatase (BALP) ;③Index of osteoclast activity: ELISA was used to detect serum Tartrate-resistant acid phosphatase (TRAP);④bone mineral density (BMD): whole body BMD of rats were measured by dual energy X ray absorptiometry ;⑤Index of endocrine: ELISA was used to detect serum concentration of estrogen ;⑥ultra structure of bone cell: transmission electron microscopy was used to examine the ultra structure of various bone cells on tibia fracture healing .Results: (1) postmenopausal osteoporosis (PMOP) models induced by oophorectomy , the survival rate of oopharectomy rats was 96% (48/50).BMD of oopharectomy group was significantly lower than the control group (P <0.01), to explore the pathogenesis of postmenopausal osteoporosis and to evaluate the drug efficacy and other research provided by the important basis of animal models. (2) By using direct vision transverse cut nail fixation, established a good osteoporotic fracture (OPF, Osteoporotic Fracture) animal models, OPFM group survival rate was 92.5% (37/40), this method has some advantages, such as accurate positioning, convenient cutting method, reliability of intramedullary nailing fixation, maintaining the comparability of fracture healing, etc., for future clinical orthopedic and dental's osteoporotic bone fracture healing, loosening of prosthesis provided by the important basis of animal models .(3) Radiology:①Post-op 5 weeks, CFM group's X-ray already showed the continuity of fracture callus, high callus density, blurred fracture lines;②OVX group showed cloudy fracture callus, sloppy, low density, still clearly visible fracture line;③using a combination of estrogen and plant-estrogen treatment increased fracture callus density, continuity was better with fuzzier fracture line.(4) osteoblast Results:①The OVX group after oopharectomy BGP, BALP were significantly increased, compared to the CFM group was significantly different, P <0.05, confirmed in rats after oopharectomy significantly increased bone cell activity;②using a combination of estrogen and plant-estrogen treatment, the rats BGP, BALP significantly reduced, there were statistically significant differences between OVX + E group, OVX + MZ group, OVX + LZ group and OVX group's BGP, BALP level, P <0.05, However, OVX + HZ group of castrated rats did not reduce the effect of TRAP, no statistical significance compared with the OVX, P> 0.05. (5) osteoclast activity results:①OVX group after oopharectomy, TRAP was significantly increased, compared with the CFM group, P <0.05, confirmed in rats after oopharectomy significantly increased the osteoclast activity.②combination of estrogen and plant-estrogen treatment, the rats bone density were significantly lower, OVX + E group, OVX + MZ group, OVX + LZ group compared with the OVX group differences were statistically significant, P <0.05, but OVX + HZ group of castrated rats did not reduce the effect of TRAP, no statistical differences compared with the OVX, P> 0.05.(6) BMD measurements:①OVX group BMD decreased significantly compared with the CFM, P <0.05, proved the success of rat osteoporotic fracture model.②combination of estrogen and plant-estrogen therapy, significantly improved bone mineral density in rats, the difference were significant in comparison between OVX + E group, OVX + MZ group, OVX + LZ group BMD and OVX group, P <0.05, but OVX + HZ group of castrated rats did not increase BMD, no significant difference with OVX, P> 0.05.(7) endocrine test results:①after oopharectomy, OVX E2 group was significantly lower compared with the CFM, P <0.05;②Application of conjugated estrogen and phytoestrogen intervention, significantly increased serum E2, OVX + E group, OVX + HZ group, OVX + MZ group, OVX + LZ group compared with the OVX group differences were statistically significant, P <0.05 ;③OVX + E group and a-ZAL each dose group comparison had no significant difference, P> 0.05(8) The results of bone cell ultra structure:①CFM Group: bone matrix of collagen fibers arranged in dense; a larger number of osteoblasts, bulky, abundant cytoplasm, rough endoplasmic reticulum and more; see a small amount of trabecular bone around the osteoclast ;②OVX group arrangement of collagen fibers in bone matrix loose large number of osteoblasts, but diverse in shape, organelle developed; osteoclast common;③application of conjugated estrogen and phytoestrogen intervention, the bone matrix of collagen fibers arranged in density, a larger number of osteoblasts, smaller, little cytoplasm, containing a small amount of endoplasmic reticulum; osteoclasts abundant.Conclusions: (1) 6 months old SD rats after bilateral oopharectomy, accelerated bone loss, decreased bone strength, could maximally simulated the normal human bone loss in postmenopausal status, 3 months after successfully established experimental animal model of osteoporosis.(2) new phytoestrogen a-ZAL and animals estrogen have the same effect, could reduce serum BGP, BALP, TRAP level,improve BMD level,increase estrogen level,enhance bone cell function, promote the growth of callus fracture of osteoporotic fracture in postmenopausal and promote healing.
|
PDF Full Text Request