The Effect Of Adiponectin And Leptin And Body Composition On Bone Mass Loss Induced By Exercise

Objective:Model of bone mass induced by training was established through progressive increasing load to the female SD rats which. To investigate the effect of adiponectin and leptin and body composition on bone mass loss induced by exercise, we analyzed the changes of BMD, E2, body composition, and adiponectin, leptin expression in rat right distal femur by immunohistochemistry (IHC-P).Method:190 three-month SD female rats were divided into training group (n=100), control group (n=90) randomly. The training group rats were trained by progressive increasing load on rat treadmill, and control group did not undertake training. To observe the change of estrous cycle, we checked change of vagina castoff cells to rats four days consecutively every week. The samples were taken at 4w, 9w, 13w, 15w and 17w respectively. BMD and E2 in serum was tested, the expression of adiponectin and leptin in osteoblast of right distal femur was observed by IHC-P.Results:1.The BMD of training group had a very significant decrease compared with control group rat 15w, 17w (P<0.01).2. The serum E2 concentration of control group were very significant higher than training group at 13w, 15w and 17w. (P<0.01).3. The percentage of body fat(PBF) of training group were very significant lower than control group at 9w, 13w, 15w and 17w(P<0.01). Intra-abdominal fat mass of training group were very significant lower than control group at 4w, 9w, 13w, 15w and 17w(P< 0.01).4.The adiponectin stain of right distal femur in training group were darker than control group at 4w, 9w, 13w, 15w and 17w, whereas the change of leptin was on contrary. The stain in control group were weaker and had no change.Conclusions:1. Model of bone loss induced by training was established successively through 17weeks progressive increasing load training.2.The concentration of serum E2 and ovarian weight of training group were significant lower than control group during 17 weeks training. This results indicated that long-term over load training could lead to hypothalamus-pituitary-ovary (HPO) axis suppression, then concentration of serum E2 decreased, which is the important factors lead to bone mess loss.3. Through analyzing the results of adiponctin and leptin IHC, we conclude that adiponectin and leptin could regulate bone metabolism in the process of bone mass loss.