BETATROPHIN ACTS AS A DIAGNOSTIC BIOMARKER IN TYPE 2 DIABETES MELLITUS AND IS NEGATIVELY ASSOCIATED WITH HDL-CHOLESTEROL

BETATROPHIN ACTS AS A DIAGNOSTIC BIOMARKERIN TYPE 2 DIABETES MELLITUS AND IS NEGATIVELY ASSOCIATED WITH HDL-CHOLESTEROLMin Yi, Rong-ping Chen, Rui Yang, Xian-feng Guo, Jia-chun Zhang, and Hong ChenINTRODUCTIONInternational Diabetes Federation (IDF), 360 million individuals suffered from diabetes in 2011, expected to rise to 522 million with a prevalence of 7.7% in 2030

Betatrophin, a newly characterized circulatory hormone secreted by liver and adipose tissues, is believed to promote cell proliferationCirculating betatrophin levels are elevated in type 2 diabetes and obesity and is involved in lipid metabolismMATERIALS AND METHODSStudy Population :131 Chinese subjects (69 males and 62 females).58 non-diabetes-mellitus subjects (NDM: 18 lean, 22 overweight, and 18 obese individuals).73 patients with T2DM (22 lean, 29 overweight, and 22 obese individuals).

Materials and MethodsAnthropometric and Biochemical MeasurementsAnthropometric : height, weight, and waist and hip circumferences, body mass index (BMI) & waist-to-hip ratio (WHR).Biochemical : Fasting plasma glucose, insulin level, C peptide, total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), uric acid, aspartate aminotransferase (AST), alanine aminotransferase (ALT), and betatrophin concentrationsRESULTSCirculating Betatrophin Levels Are Significantly Increased in T2DM and Obese Subjects.

Figure 1: Serum betatrophin concentrations in each subgroup.

RESULTSBetatrophin Is Negatively Associated with HDL-C Levels in All SubjectsBetatrophin amounts were correlated only with age and HDL-cholesterol levelsWhen stratified by BMI, betatrophin is negatively associated with HDL-C levels in all subgroups

Table 2: Correlations between betatrophin levels and various parameters of the study subjects.

RESULTSPerformance of Betatrophin Concentration in DetectingThe ROC curve shown the diagnostic accuracy of betatrophin level for T2DMThe optimal cut-off point (betatrophin concentration) to predict T2DM was 501.23 pg/mL. (sensitivity : 83.56% and specificity : 72.41%)

Figure 3: Receiver operating characteristics (ROC) curves showing the performance of betatrophin concentration in detecting type 2 diabetes mellitus.DISCUSSIONBetatrophin is believed to promote pancreatic beta cell proliferation and to improve metabolic control by increasing beta cell division rate in insulin resistant mice.We found that circulating betatrophin concentrations were significantly increased in T2DM and obese patients.DISCUSSIONMultiple animal-based studies proposed that betatrophin level is closely related to altered blood lipid metabolism.Betatrophin may affect blood lipid profiles by regulating hepatic VLDL secretion and altering LPL activity.Betatrophin may also act via a functional interaction with ANGPTL3 a lipid regulator, which regulates HDLC levels by inhibiting endothelial lipaseDISCUSSIONAnother novel finding of this study is that betatrophin could be used as a diagnostic biomarker for T2DM.However, further studies in betatrophin/Angptl8 knockout mice do not support a role for betatrophin in controlling beta cell growth.DISCUSSIONBetatrophin is much more likely to be a diagnostic biomarker rather than a potential therapeutic target for type 2 diabetes.If betatrophin can be a reliable diagnostic biomarker and classification index for diabetes, it would be an important indicator to distinguish type 1 from type 2 diabetes.DISCUSSIONLimitations :Sample size was relatively small.The research was a cross-sectional study, which could not address the cause-effect relationship.This trial only estimated serum betatrophin levels at a single point, which cannot reflect betatrophin levels over time.CONCLUSION Circulating betatrophin levels are elevated in type 2 diabetes and obese subjects.Circulation betatrophin concentrations could be a diagnostic biomarker for T2DM.There is a negative correlation between serum betatrophin levels and HDL-cholesterol amountsThank you