Effects Of Different Exercises On The Expression Of Correlated Factors Of Bone-Gonadal Axis In Mice

Testosterone plays a very important role in the growth and development of young men.Hypothalamic-pituitary-gonadal axis(HPG axis)has been the focus of traditional research in the testosterone synthesis and secretion.In recent years,the study found that the secretion of bone can also cause testosterone levels in males.Bone can be used as an endocrine organ.When osteocalcin(OCN)secreted by bone is decarboxylated,it forms active ucarboxylated Osteocalcin(uOCN).uOCN can induce the change of receptor in testis tissue through blood circulation and cause the expression of downstream factors through cAMP/CREB signal pathway,finally it improves the synthetic changes of testosterone in male.There has been lots of research on the motor intervention of the HPG axis,but there is relatively little discussion on the bone-gonadal axis.In this study,by means of different exercise modes,the intrinsic relationship between bone and testosterone secretion was studied in order to provide rationale and data support for exercise to improve the bone-gonadal axis.Purpose:The paper explores the regulation mechanism of down-jumping,swimming and running on the bone-gonadal axis of male mice in the growth period,and compares the stimulation effect of different exercise modes on bone health and explore the effect of exercise on improving bone health.The possible mechanism of testosterone secretion in tissues provides theoretical basis and data support for exercise to improve male reproductive level.Methods:28 male C57BL/6 mice of 5-week old were adapted for 1 week and randomly assigned to control group(C),down-jumping group(D),swimming group(S)and running group(R),each group had 7 mice.Let them eat and drink in conventional cage and natural light ratio of 1:1(24h).The frequency of group D was 6-7 times/min.The device in group S(100cm×60cm×80cm),water depth 40cm,temperature 32±2?.Group R is in the condition of 0.8 km/h and slope is-9~°.The first week of exercise adaptive training,20min in 1,2 days,35min in 3,4 days,50min in 5,6 days;After each training is directly 50min training intensity.After 8 weeks,the mice were sacrificed by cervical dislocation,blood samples were taken for detection of relevant indexes,weight of the mice,wet weight of the right femur and wet weight of the right tibiofibular bone were weighed.The vernier caliper was used to measure the bone length and width,The skeletal and testicular tissues were examined for mRNA and protein expression.Results:1)Compared with group C,the femoral wet weight of mice in group D and group R increased significantly(P<0.05),the femur length of group R increased significantly(P<0.05);Compared with group S,the femoral wet weight of mice in group D and group R increased significantly(P<0.01),the femur length of group D and group R increased significantly(P<0.01),the length of tibia in group R increased significantly(P<0.05),the width of tibia in group D increased significantly(P<0.05).This shows that exercise is beneficial to the length and width of bone.2)Compared with group C,the OCN mRNA and protein expression of bone in group D increased significantly(P<0.05),the OCN mRNA and protein expression of bone in group R increased significantly(P<0.01);Compared with group S,the OCN m RNA expression of bone in group R increased significantly(P<0.05);Compared with group C,the testicular uOCN content in group R increased significantly(P<0.05).This shows that exercise improves bone endocrine levels.3)In testis tissue changes,compared with group C,the mRNA expression of GPRC6A in group R increased significantly(P<0.05),the expression of CREB protein in group R increased significantly(P<0.05),the expression of pCREB protein in group R increased significantly(P<0.01),the changes of CREB protein activity in group R increased significantly(P<0.05);Compared with group S,the expression of CREB and pCREB protein in group R increased significantly(P<0.05).This suggests that the exercise activates the cAMP/CREB signal.4)Compared with group C,the mRNA expression of Cyp11a in group R increased significantly(P<0.05),the mRNA expression of StAR,3?-HSD and Cyp17 in group R increased significantly(P<0.01),the mRNA expression of 3?-HSD in group D and group S increased significantly(P<0.05);Compared with group S,the m RNA expression of StAR,Cyp11a and Cyp17 in group R increased significantly(P<0.05).These reflect the increased expression of related active factors caused by bone endocrine secretion.5)Compared with group C,group D and group S,testicular testosterone content in group R was significantly higher(P<0.01);Compared with group C and group D,the level of serum testosterone in group R was significantly increased(P<0.05).This shows that running is beneficial to increase testosterone levels and blood testosterone secretion.Conclusions:(1)Compared with jumping and swimming,running is more likely to stimulate the growth and development of the bone,causing grow in length and width,ultimately improving the quality of the bones and improving the endocrine system,resulting in the secretion of OCN.(2)Running induced a further increase in the level of GPRC6A and further activation of cAMP/CREB signaling pathway,resulting in significant increases in the expression of downstream factors such as StAR,Cyp11a,3?-HSD and Cyp17,thereby increasing the level of testosterone synthesis in testicular tissue And serum testosterone secretion increased.