Role of toll receptors in diabetic nephropathy

Mona Mansour, Randa Fayez Salam, Lila Rashed, Heba Salam

Internal Medicine Department, Cairo University, Cairo, Egypt.
Medical Biochemistry Department, Cairo University, Cairo, Egypt.

DOI: 10.4236/jdm.2014.41005                

Abstract

Objectives: Diabetic nephropathy is the leading cause of chronic kidney disease. The pathogenesis of DN remains incompletely understood. It has been recently demonstrated that inflammatory processes play a significant role in the development and progression of DN. Toll-like receptors play a fundamental role in the innate immune system by triggering proinflammatory signaling pathways. Our aim is to evaluate the expression of TLRs on monocytes and relate their expression with inflammation in HD patients with & without diabetic nephropathy. Method: In a case control study (60) patients from Alkasr El Aini Hospital on hemodialysis were divided into two groups: Group 1, 30 patients on heamodialysis not due to diabetic nephropathy, Group 2, 30 patients on heamodialysis due to diabetic nephropathy, compared to Group 3, including 30 healthy controls. All participants were subjected to: Full medical history, complete physical examination, Serum creatinine, uric acid, A1C, fundus examination, detection of TLR2, TLR expression by real time PCR in peripheral blood mononuclear cells. Data were statically calculated using SPSS, comparision between groups was done using student T test comparing 2 groups, correlation using spearman’s correlation. Results: Diabetic had significantly increased TLR2, TLR4 mRNA in peripheral blood mononuclear cells compared to controls and non diabetics patient on heamodialysis (p < 0.001), TLR2, TLR4 significantly correlated with dialysis duration in diabetic (p < 0.001), no correlation with A1C in relation to TLR2 (p = 0.078), TLR4 (p = 0.163). Conclusion: TLR2, TLR4 were significantly elevated in diabetic on dialysis initiating event in the pathogenesis of DN, providing a link between hyperglycemia and hypoxia with inflammation and fibrosis within the kidney. Hence, therapeutic interventions aimed at targeting the inflammatory component through interruption of TLR signaling may be a novel strategy to target prevention and treatment of DN.

Keywords

Diabetic Nephropathy; Toll Receptor 2, 4

Conflicts of Interest

The authors declare no conflicts of interest.

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