Serum and Urinary Fatty Acid-Binding Protein 1 Levels as Markers for Diabetic Nephropathy in Type II Diabetes Mellitus

Background:Diabetic nephropathy is considered a main microvascular complication of diabetes mellitus (DM) that results in chronic renal failure. Fatty acid-binding protein 1 (FABP1) is expressed in renal proximal tubule cells and released into urine as a result of hypoxia triggered by decreased peritubular capillary blood flow, consequently urinary FABP1 is seen as a hopeful indicator for monitoring tubulointerstitial injury. There is increasing evidence that FABP1 plays a role in the development and progression of chronic kidney disease. Aim: This study aimed to assess the correlation of circulating plasma FABP1 level as well as its urinary level to nephropathy in patients with type 2 diabetes mellitus.Methods: Ninety patients were recruited, divided into 3 groups. They were investigated for glycemic and renal biomarkers, then FABP1 concentration was measured in their serum and urine samples. Bioinformatic analysis was done to explore the relation between FABP1 and DN. Results: The presence of DN was associated with increase in both serum and urinary FABP1. A serum FABP1 concentration of >243 ng/L was associated with DN, with a sensitivity of 93% and specificity of 90%, while urinary FABP1 concentration of >155.67 ng/L was associated with DN, with a sensitivity of 90% and specificity of 73%. Bioinformatic analysis revealed interactions between FABP1 and other kidney markers. Conclusion: This study proved that serum and urinary levels of FABP1 were significantly higher in the DN group than the normo-albuminuric groups reflecting the progression of the disease, thus they can be used as diagnostic biomarkers with significant sensitivity and specificity.