Plasma Concentrations Of Platelet Factor 4 Research Articles

Increased plasma concentration of vascular endothelial growth factor in patients with atopic dermatitis and its relation to disease severity and platelet activation

BackgroundOverproduction of vascular endothelial growth factor (VEGF) in atopic dermatitis (AD) lesions has previously been observed. It is also known that platelet is an important source of VEGF and platelet factor 4 (PF-4), a potential marker of AD severity.AimTo evaluate concentrations of VEGF and its soluble receptors (sVEGF-R1 and sVEGF-R2) in the plasma of AD patients and to examine its possible correlation with disease severity and plasma concentrations of PF-4, a platelet activation marker.MethodsPlasma concentrations of VEGF and its receptors and levels of PF-4 were measured by an immunoenzymatic assay in 51 AD patients and in 35 healthy non-atopic controls. The severity of the disease was evaluated using the eczema area and severity index.ResultsAD patients showed significantly increased VEGF and PF-4 plasma concentrations as compared with the controls. Plasma concentrations of sVEGF-R1 and sVEGF-R2 did not differ between the groups. There were no remarkable correlations between plasma VEGF concentration and disease severity or between VEGF and PF-4 concentration.ConclusionsThis study shows that plasma concentration of VEGF may be increased in patients suffering from AD. It seems that plasma VEGF concentration is not a useful marker of disease severity and, apart from platelets, other cells might also release the cytokine.

Depression and platelet activation in outpatients with stable coronary heart disease: Findings from the Heart and Soul Study

Depression is associated with increased morbidity and mortality in patients with coronary heart disease (CHD). Increased platelet activation has been proposed as a potential mechanism by which depression may lead to adverse cardiovascular outcomes. In this cross-sectional study, we measured platelet activation in 104 patients with stable CHD, including 58 with a current episode of major depression and 46 without past or current major depression. Participants were instructed not to take aspirin for 7 days prior to the study appointment. Platelet activation was measured by plasma concentrations of platelet factor 4 (PF4) and beta-thromboglobulin (β-TG), and by 24-h urinary concentrations of 11-dehydro-thromboxane B 2 (TBXB2). We observed no differences in the mean levels of PF4, B-TG or TBXB2 in patients with and without major depression. Results were unchanged after adjustment for age, smoking, use of aspirin, and use of any psychotropic medication. We found no evidence of an association between major depression and platelet activation as measured by plasma concentrations of PF4 and β-TG, or urinary TBXB2 in 104 outpatients with stable CHD. These findings do not support a role for platelet activation in the association between depression and cardiovascular disease among patients with stable CHD.