Study of selected cytokines [tumour necrosis factor -alpha and interleukin-18] in patients with diabetic nephropathy

ABSTRACT

The aim of the present study was to investigate tumour necrosis factor- alpha [TNF-alpha] and interleukin-18 [IL-18] levels, their roles in the pathogenesis of diabetic complications especially diabetic nephropathy. Sixty patients with diabetes mellitus [30 with type 1 insulin dependent diabetes mellitus [IDDM] and 30 with type 2 non -insulin dependent diabetes mellitus [NIDDM] patients and 20 healthy controls were studied. Serum TNF-alpha and IL-18 was measured by enzyme linked immunosorbent assay [ELISA] for all subjects. In addition, fasting blood sugar [FBS], 2 h postprandial blood sugar [2h PPBS], glycosylated hemoglobin [Hb[AIC]], urinary albumin levels, triglyceride, total cholesterol, low density lipoprotein cholesterol [LDL-c], and high density lipoprotein cholesterol [HDL-c] were performed for all subjects. Increased serum levels of TNF-alpha and IL - 18 was evident in both IDDM and NIDDM patients as compared to the control group. Similarly, their levels in patients with diabetic nephropathy increased gradually according to the clinical stage of the disease, being highest in macroalbuminuric stage. Correlation analyses showed that serum TNF-alpha and IL-18 concentration were positively correlated with each other and positively with FBS,2h PPBS, Hb[A1C], triglyceride and urinary albumin excretion levels and negative correlation between TNF-alpha and HDL-c were also found in diabetic subjects. In conclusion, high serum levels of TNF-alpha and IL-18 suggested that they might play a role in the pathogenesis of diabetes mellitus [DM] and in the development of nephropathy in diabetic patients whether of type 1 or 2