Abstract

Endothelial dysfunction is a common feature in type-2 diabetic patients and is associated with inflammation, increased levels of circulating soluble adhesion molecules and atherosclerosis. Insufficiency of tetrahydrobiopterin leads to uncoupling of the nitric oxide synthase enzyme an endothelial dysfunction.

The aim of this study: was to evaluate if there is a relationship between the levels of circulating soluble adhesion molecules and the levels of biopterins in normotensive type-2 diabetic patients.

Methods: We studied 30 normotensive type-2 diabetic patients in whom VCAM-1, ICAM-1 and E-selectin were measured by ELISA. Additionally, Biopterins were measured by reverse phase high performance liquid chromatography with fluorescence detection. The levels of circulating adhesion molecules and biopterins were correlated using the Spearman correlation coefficient test. Statistical analysis was performed with ANOVA.

Results: We did not find any relationship between absolute values of biopterins and soluble adhesion molecules. However, we observed significant inverse correlations between the BH4/BH2 ratio and VCAM-1 (r= -0.65, p<0.001) with ICAM-1 (r= -0.69, p< 0.001) and with E-selectin (r=-0.64 p<0.001),

Conclusion: Our data suggest that systemic levels of adhesion molecules have an inverse association with the BH4/BH2 ratio in type 2 diabetic normotensive patients.

Keywords: Endothelial dysfunction, inflammation, soluble adhesion molecules, tetrahydrobiopterin, Type-2 diabetes, Tetrahydrobiopterin, nitric oxide synthase, dihydrobiopterin, nuclear factor kappa-B, ICAM-1, VCAM-1.