Diabetes has been shown to be an accelerating factor in the progression of atherosclerosis. The metabolic changes in diabetes contribute to modified platelet function and enhanced leukocyte-platelet aggregate formation. The attachment of activated platelets leads to the activation of leukocytes causing enhanced cytokine production and upregulation of surface adhesion molecules. Therefore, platelet-leukocyte aggregates may be of great importance in the development of cardiovascular complications.
Monocyte-platelet aggregates and monocyte Mac-1 expression were measured by flow cytometry to obtain differences between type 2 diabetic and healthy subjects. Inflammatory mediators were evaluated to assess the presence of inflammation.
We found no signs of inflammation in type 2 diabetes; however, we observed enhanced aggregation level of monocytes and platelets. The expression of Mac-1 did not differ between diabetic and control subjects, but it was significantly higher on monocytes bearing platelets in both groups.
Elevation of monocyte-platelet aggregates is an early marker of diabetes, which precedes the signs of inflammation. Enhanced Mac-1 expression can be observed on monocytes bearing platelets, independent from the presence of diabetes.
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