Concentrations of circulating P-selectin are increased in patients with newly diagnosed insulin-dependent diabetes mellitus.

Endothelial cell activations and/or dysregulations of the coagulation system are crucial parameters for the prognosis of disease in patients with IDDM. Recent data suggest that expression of the adhesion molecules E-selectin and P-selectin are markers of endothelial cell activation and/or platelet activation and might modify immunologic responses after shedding from cell membranes. In patients with newly diagnosed IDDM only limited data on circulating selectins are available. This has prompted us to measure levels of soluble (s) forms of P-selectin and E-selectin in 18 patients with newly diagnosed IDDM and two years after the onset of insulin substitution therapy in comparison to 18 age-matched healthy control subjects. HbA1c and blood glucose levels were significantly higher in patients with new onset diabetes, compared to the same patients after two years of insulin therapy (HbA1c: 12 +/- 3% vs. 7.8 +/- 2%; p < 0.01; blood-glucose: 409 +/- 163 mg/dl vs. 131 +/- 23 mg/dl; p < 0.01), but no correlation between these metabolic parameters and soluble forms of E- and P-selectins were noted. Levels of sP-selectin decreased from 210 +/- 120 ng/ml in newly diagnosed IDDM patients to 127 +/- 75 ng/ml after two years of therapy (p < 0.01) and were similar to those of the control subjects (110 +/- 31 ng/ml). Serum concentrations of circulating E-selectin showed no differences in the three groups (newly diagnosed IDDM: 42 +/- 17 ng/ml; two years later: 43 +/- 19 ng/ml; control subjects: 41 +/- 14 ng/ml; n.s.). Increased levels of sP-selectin together with normal levels of sE-selectin at the onset of IDDM suggest enhanced platelet activation during the initial phase of the autoimmune process and return to baseline levels within two years of the disease.