Oxidized-LDL, Toll-like Receptor 4, Lipocalin 2 and Omentin1: Role in Diabetic Nephropathy

Background: Diabetic nephropathy is the major micro-vascular complication of type 2 diabetes mellitus (T2DM) and is the main cause for end-stage kidney disease. In view of metabolic derangements of T2DM, we went further to investigate the role played by oxidized low density lipoprotein (ox-LDL), toll like receptor 4 (TLR4), lipocalin-2 (LCN2), and omentin-1 in DN.

Patients and Methods: 15 normo-albuminuria T2DM, 15 micro-albuminuria T2DM and 15 macro-albuminuria T2DM in addition to 15 apparently healthy volunteer who served as control group were enrolled in this study. Demographic and clinical data were recorded. Plasma Ox-LDL, omentin- 1 and urinary LCN2 levels by immunoassy and TLR4 mRNA level with real time PCR were assessed. Results: TLR4 gene expression, Plasma ox-LDL, urinary LCN2 levels were increased in T2DM cases as compared to their allied control group with the higher values were for macro-albuminuria T2DM cases. Meanwhile Plasma omentin-1 level was decreased in T2DM cases when compared to their allied control group with least values were for macro-albuminuria T2DM cases. Also there were positive correlations between TLR4 mRNA, ox-LDL, urinary LCN2 levels and serum creatinine, fasting blood glucose, urinary albumin/creatinine ratio. Meanwhile, omentin 1 showed negative correlations with serum creatinine, fasting blood glucose, urinary albumin/creatinine ratio. Conclusions: Ox-LDL, TLR4, LCN2 and omentin 1 may confer a relevant role in diabetic nephropathy development and progression.