Lipocalin-2 expression and serum levels as early predictors of type 2 diabetes mellitus in obese women.

Obesity and diabetes are increasing in epidemic proportions globally. Lipocalin-2 (LCN-2) is an inflammatory adipocytokine and obesity-related marker of low-grade inflammation. We aimed to investigate, for first time, the possible role of LCN-2 expression and serum levels in prediction of impaired glucose tolerance (IGT) and type 2 diabetes mellitus (T2DM) among obese Egyptian women. This study included 188 obese women and 180 controls. Obese women were subdivided into three subgroups according to their fasting blood glucose, normal glucose tolerance (NGT), IGT and T2DM. Circulating LCN-2 expression levels were determined by real time polymerase chain reaction. Serum LCN-2 concentrations were assessed by ELISA. Our findings revealed that LCN-2 expression and serum levels were higher in obese women compared to lean controls. They were higher in IGT and T2DM obese cases than in NGT obese women. Receiver operating characteristic analyses revealed that LCN-2 expression level was a useful biomarker discriminating IGT from NGT and T2DM from IGT obese women (AUC were 0.735 and 0.740, respectively). It was an independent predictor of IGT and T2DM among obese women. Serum LCN-2 level was a useful biomarker discriminating IGT from NGT and T2DM from IGT obese women (AUC were 0.705 and 0.728, respectively). It was independent predictor of T2DM without predicting IGT among obese women. The power of combined LCN-2 serum levels and expression in discriminating between IGT from NGT and T2DM from IGT obese women was high (AUC = 0.717 and 0.741, respectively). In conclusion, LCN-2 expression and serum levels could discriminate IGT from NGT and T2DM from IGT obese women and early predicting T2DM among obese women. While, LCN-2 expression level was the independent predictor of IGT in obese women. Combination of both LCN-2 expression and serum levels improved their diagnostic value in early detection of IGT and T2DM among obese women.