Prevention Of Weightless Bone Loss In Rats With Atractylodes Macrocephala Polysaccharide By Regulating Immunity

In recent years,bone loss caused by weightlessness has become the focus of space medicine research,but the prevention of bone loss in microgravity environment remains to be explored.In this paper,the traditional Chinese medicine Atractylodes macrocephala was used as the experimental material.The experiment period was 28 days.The rats were divided into three groups: ground control group,simulated deregulation group,low dose group(20 mg/kg/d),medium dose group(60 mg/kg/d),high dose group(100mg/kg/d).In order to understand the growth status of rats,the body mass was measured every 7 days during the feeding period.after 28 days of tail hanging,the materials were taken for the study of bone histology and Immunology level.The three-point mechanical bending test was used to screen the effective concentration of Atractylodes macrocephala polysaccharide against bone loss,and then the change of bone marker protease activity was detected from the physiological level.immunology level study The changes of immune factors(IL-6 and TNF-α)in immune organs(thymus and spleen),serum and colon were studied.The results showed that after simulated microgravity,the mechanical properties of bone tissue decreased significantly,the activity of bone marker enzymes changed,and the bone metabolism was disordered,while the middle dose group of Atractylodes macrocephala polysaccharide(60 mg/kg/d)the mechanical index of femur of rats tended to normal level,the activity of bone marker enzyme tended to normal level,and the bone metabolism was in balance.The results of immunology showed that the intestinal immune state and the systemic immune function of rats were changed after tail suspension,but the immune state of rats in Atractylodes macrocephala polysaccharide treatment group did not change significantly.In conclusion,Atractylodes macrocephala polysaccharide can prevent the occurrence of weightlessness bone loss in rats to a certain extent.Under weightlessness condition,the immune system function of rats is also disordered.The administration of Atractylodes macrocephala polysaccharide can prevent the decrease of immune function,but the best concentration of drug,which specific component of crude polysaccharide plays a role,and the molecular mechanism of Atractylodes macrocephala polysaccharide in the treatment of bone loss remains to be further studied.