Proinflammatory monocyte polarization in type 2 diabetes mellitus and coronary heart disease

Aim: Type 2 diabetes mellitus (T2DM) is associated with rapid progression of atherosclerosis. There is no doubt that inflammation is involved in atherogenesis. Recent studies showed the relationship between the development of atherosclerotic plaque formation and the amount of pro-inflammatory (M1) activated macrophages in situ.Methods: The authors studied the ability of circulating monocytes isolated from patients with diabetes (n = 28), coronary heart disease (CHD) (n = 27) and healthy subjects (n = 50) to be activated into M1 phenotype in vitro.Results: Increased levels of basal and stimulated secretion of tumor necrosis factor alpha (TNF-α) was observed in diabetic patients compared with healthy subjects. On the contrary, in patients with CHD, decreased secretion of the pro-inflammatory cytokine, TNF-α, was found. A direct correlation between glycated hemoglobin (HbA1c) levels in T2DM patients and basal secretion of TNF-α from monocytes was observed.Conclusion: The authors found diametrically different responses of monocytes from T2DM and CHD under pro-inflammatory stimuli