K Gokulakrishnan
Madras Diabetes Research Foundation, India
Aim: Secreted frizzled-related protein 4 (SFRP4) is highly expressed in islets and found to cause five times more risk of diabetes. Betatrophin is a secreted protein involved in beta cell replication with a potential role in type 2 diabetes. We comparatively investigated the role of SFRP4 and betatrophin as potential biomarkers of beta cell dysfunction in youth-onset T2DM (T2DM-Y) participants. Methods: We recruited 100 individuals, normal glucose tolerance (NGT) n=50 and newly diagnosed cases of T2DM-Y [n=50] with onset between 12 to 24 years of age. Insulin resistance was measured by HOMA-IR and beta cell function by oral disposition index (DIo). SFRP4 and betatrophin levels were measured by the enzyme-linked immunosorbent assay. Results: The mean plasma levels of SFRP4 were higher in T2DM-Y compared to NGT [199 vs. 55 ng/ml, p<0.001]. Conversely, betatrophin levels were lower in T2DM-Y [803 vs. 1104 pg/ml, p<0.001]. SFRP4 was positively correlated with HOMA-IR (p<0.01) and negatively with DIo (p<0.01) whereas betatrophin showed an inverse correlation with HOMA-IR (p<0.001) and a positive correlation with DIo (p=0.012). Regression analysis showed that higher levels of SFRP4 were associated with T2DM-Y [odds ratio (OR) 1.297, 95% CI: 1.135-1.481; p<0.001]. Lower levels of betatrophin were independently associated with T2DM-Y [OR: 0.521, 95% CI: 0.326-0.885, p=0.014]. However, the association was lost when HOMA-IR was included in the model. Conclusion: In young Asian Indians, the circulatory levels of SFRP4 are positively and betatrophin negatively associated with T2DM-Y, beta cell dysfunction and could serve as biomarkers of T2DM-Y.
Email: gokulmdrf@gmail.com
