Correlation Between Osteocalcin And Visceral Fat Area In Overweight And Obese Male Population

Background and objectives According to the distribution of body fat,obesity is divided into peripheral obesity and abdominal obesity.Belly fat mainly by the abdominal visceral fat and abdominal subcutaneous fat,also known as central obesity or visceral obesity.Visceral fat metabolic activity was significantly higher than subcutaneous fat,this high metabolic activity and hypertension,abnormal glucose metabolism are closely related,while increasing the incidence of cardiovascular disease.In previous studies,osteocalcin has long been recognized as a marker of bone formation and bone turnover.However,osteocalcin(OC)is now found to be closely associated with insulin,adiponectin(APN)secretion and abdominal obesity.For example,in a study by Shanghai Sixth Hospital,quantitative determination of abdominal fat distribution by magnetic resonance imaging showed that serum osteocalcin levels were negatively correlated with visceral fat area in the male population.Here,this research is the first study to analyze the correlation between the serum OC level and visceral fat area of overweight and obese people in our province,suggesting that there exists interaction between bone and adipose tissue which affected the distribution of body fat.All of these findings were of great significance for the evaluation of the degree of insulin resistance of obesity,diabetes and other metabolic disorders and of great clinical value to assess the cardiovascular metabolic risk and to guide the treatment.Methods 1.Seventy subjects aged from 35 to 75 years(52.13±7.21 years),who underwent physical examination and hospitalization,were selected from Clinic for Retired Veteran Cadres of Anhui Provincial Hospital.All subjects were divided into three groups according to body mass index(BMI):control group(n=26),overweight group(n=20)and obese group(n=24).Medical history and lifestyle of all the subjects were obtained.Metabolic parameters,including fasting blood glucose(FBG),2 hour plasma glucose after glucose load(2h PG),triglyceride(TG),total cholesterol(TC),C reactive protein(CRP),high density lipoprotein cholesterol(HDL-C),low density lipoprotein cholesterol(LDL-C),and serum levels of OC,adiponectin(APN)and visceral fat area(VFA),waist circumference(WC),fasting insulin(FINS),insulin resistance index,were evaluated before and after the treatment and the differences between groups were compared.The insulin resistance index was estimated by homeostasis model assessment of insulin resistance(HOMA-IR)while visceral fat area(VFA)was quantified via magnetic resonance imaging.2.By comparing the differences of serum OC levels,VFA,and various metabolic indices between the three groups,the correlation between serum OC levels and VFA,as well as blood lipids,blood glucose,blood pressure,and CRP,and the relationship between serum OC levels and abdominal obesity were studied.Statistical analysis was performed on the collected data using SPSS software 13.0.Results Compared with the other two groups,BMI,FINS,WC,HOMA-IR,LDL-C and CRP was higher in the obesity group(P <0.05).Compared with the control group,FPG,TG,TC in obesity group were significantly increased(P <0.05),while HDL-C was significantly decreased(P <0.05).Age,blood pressure,There was no significant difference(P> 0.05)among the three groups.The level of OC in obesity group was lower than that in overweight group(P <0.05),while that in overweight group was lower than that in control group(P <0.05).Compared with the overweight group and the control group,the abdominal fat area of the obese group increased significantly(P <0.01).The levels of serum OC in the overweight and obesity groups were significantly lower than those in the control group(P <0.05).the OC level was signifcantly correlated with WC(r=-0.532,P=0.000),FINS(r=-0.416,P=0.000),HOMA-IR(r=-0.509,P=0.000),FBG(r=-0.297,P=0.037),APN(r=0.302,P=0.034),CRP(r=-0.475,P=0.000),and VFA(r=-0.325,P=0.016)in overweight and obesity groups.However,the OC level was only obviously correlated with WC(r=-0.609,P=0.000)in control group.Meanwhile,multiple linear stepwise regression analysis demonstrated that WC(standardized ?=-0.416,P=0.000),HOMA-IR(standardized ?=-0.859,P=0.005),and VFA(standardized ?=-0.497,P=0.019)were independently and inversely associated with serum OC level in overweight and obesity subjects.Conclusion With different levels of visceral fat content,the variation of OC in overweight and obese male subjects was closely related to VFA,indicating that OC might participate in the development of abdominal obesity.