Monocytes from type 2 diabetic patients have a pro-inflammatory profile:

Abstract 

The exact factors contributing to the pathogenesis of type 2 diabetes remain elusive. Lately, it was suggested that inflammation and activation of the innate immune system could be linked to type 2 diabetes pathogenesis and also to the development of common diabetic complications, mainly atherosclerosis. The aim of this study was to investigate the role of monocytes in this sub-clinical inflammatory state and test 1,25-dihydroxyvitamin D₃, the active form of Vitamin D, as an anti-inflammatory agent. For this purpose, monocytes from type 2 diabetic patients were compared to monocytes from healthy controls and type 1 diabetic patients. The expression profile of inflammatory markers in freshly isolated and immune-stimulated monocytes was measured by quantitative real-time RT-PCR. Type 2 diabetic patients showed significantly higher expression levels of TNF-α, IL-6, IL-1, IL-8, COX-2, ICAM-1 and B7-1 compared to controls and type 1 diabetic patients. 1,25-Dihydroxyvitamin D₃ was able to down-regulate the expression of TNF-α, IL-6, IL-1, and IL-8, confirming its immunomodulatory properties. From these data we concluded that monocytes from type 2 diabetic patients have a pro-inflammatory profile. In addition, 1,25-dihydroxyvitamin D₃ was able to modulate inflammation in these monocytes.

Abbreviations: 1,25(OH)₂D₃, 1,25-dihydroxyvitamin D₃, CCL-2, chemokine (C-C motif) ligand-2, COX-2, cyclooxygenase-2, CRP, C-reactive protein, CXCL-10, chemokine (C-X-C motif) ligand-10, ICAM-1, intercellular adhesion molecule-1, IL, interleukin, FW, forward primer, MGB, minor groove binding probe, PBMC, peripheral blood mononuclear cell, RT, reverse transcriptase, RV, reverse primer, T1D, type 1 diabetes, T2D, type 2 diabetes, TGF, transforming growth factor, TNF, tumor necrosis factor, TP, TaqMan probe, VDR, vitamin D receptor

Keywords: Atherosclerosis, Cytokines, Inflammation, Monocytes, Type 2 diabetes, Vitamin D