Evaluation of Serum GPR-120 Levels in Diabetic Patients With and Without Nephropathy: A Comparative Study on Lipid...

Diabetic nephropathy (DN) remains one of the main reasons for end-stage renal disease globally and is strongly related to adverse lipid profiles, oxidative stress, and chronic inflammation. The G-protein coupled receptor 120 (GPR-120), a protein implicated in lipid metabolism and anti-inflammatory pathways, has garnered recent attention as a possible diagnostic and prognostic biomarker reflecting both metabolic derangements and renal injury. However, its clinical importance in diabetic cohorts, particularly those with nephropathy, remains underexplored.

We performed a case-control study of 200 subjects (adults) with type 2 diabetes mellitus, subdivided into those without nephropathy (n=100) and those with nephropathy (n=100). All subjects underwent comprehensive biochemical profiling, such as fasting glucose, postprandial glucose, glycated hemoglobin (HbA1C), lipid indices (total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglycerides, and oxidized LDL), renal characteristic checks (creatinine, cystatin C, microalbuminuria, estimated glomerular filtration rate (eGFR)), and serum GPR-120 analyzed via enzyme-linked immunosorbent assay. We compared GPR-120 levels across both groups and performed regression analysis to investigate how GPR-120 correlates with lipid parameters and renal markers.

Subjects with nephropathy exhibited drastically lower GPR-120 concentrations (2.9 ± 0.8 ng/mL) compared to the ones without nephropathy (11.2 ± 4.5 ng/mL, p<0.001). Regression analysis revealed that HDL-C positively correlated with GPR-120 (p<0.001), while LDL-C, triglycerides, and cystatin C were negatively associated with GPR-120 (p<0.01). Microalbuminuria additionally showed an inverse relationship with GPR-120 levels. Considerably higher eGFR values predicted better GPR-120 concentrations, suggesting a defensive or compensatory mechanism.

Our findings indicate that GPR-120 is markedly reduced in DN and demonstrates strong associations with both adverse lipid profiles and renal dysfunction. The GPR-120 may represent an emerging biomarker of integrated metabolic and renal health in diabetes. Larger longitudinal studies are recommended to confirm its prognostic utility and clarify whether interventions targeting dyslipidemia could modulate GPR-120 levels.