The immunomodulatory effect 1,25 (OH)2 D3 on TLR 2 and TLR4 expression on monocytes of patients with type II diabetes mellitus

Background: Recent studies have shown the immunomodulatory effect of vitamin D3 through down-regulation of Toll-like receptor (TLR) expression in human monocytes. In this study, the effects of vitamin D treatment on TLR2 and TLR4 expression on monocytes derived from type 2 diabetes was investigated. Materials and Methods: To assess the influence of vitamin D3 on expression of TLR2 and TLR4 on monocytes from patients with type II diabetes, peripheral blood sample was taken of 30 patients. Peripheral blood mononuclear cells (PBMCs) were isolated by density gradient centrifuge and then monocytes were isolated from these cells with using the magnetic activated cell sorting (MACS). To investigate the effect of vitamin D3 on the expression of TLR2 and TLR4, monocytes were cultured in the presence of vitamin D3 (10^-9 M) for 48 hours. Then the expression of TLR2 and TLR4 was determined by Real-time PCR. Results: We found that vitamin D3 suppresses the mRNA expression of TLR2 and TLR4 in patients with type II diabetes. TLR2 and TLR4 expression in the patients exposed to vitamin D3 were significantly decreased in comparison with patients who were not treated with vitamin D3. Conclusion: It can be concluded that vitamin D3 supplements may be further analyzed as a therapeutic option by reducing TLR2 and TLR4 expression in patients with type II diabetes.