Aim: 

Vitamin D (vitD) has usually been associated with the bone health. Recently, however, there has been evidence that vitD plays an important role in several tissues including myocardium and endothelium. For example, vitD deficiency seems to predispose to a number of cardiovascular diseases (Zittermann A, Prog Biophys Mol Biol, 92:39,2006). This research was planned to test the hypothesis that vitD plays a role in nitric oxide (NO) production within endothelial cells cultures.

Methods: 

Human umbilical vein endothelial cells (HUVEC) cultures were used. Cells were treated with vitamin D3 (1-alpha,25-dihydroxycholecalciferol at various concentrations (10 pM, 100 pM, 1 nM, 10 nM, 100 nM), and at different times of administration (30s, 60s, 180s). NO production was determined by means of Griess method.

Results: 

When applied to HUVEC cultures, vitD caused a significant dose-dependent increase in NO production. The most relevant response was obtained with a vitD concentration ranging from 1 to 10 nM (+975%; p<0.05). As regards the time course of the response, 60s administration appears to induce the greatest response. Administration of the vehicle alone to HUVEC cells, induced a very limited response (+5%) in NO production.

Conclusion: 

vitD can induce an increase in NO production in endothelial cells. This finding add new information about the increasing importance of this hormone in the complex cardioprotective mechanisms that maintain cardiovascular health.