Soluble vascular endothelial growth factor, soluble VEGF receptor Flt-1 and endothelial function in healthy smokers

Objective To relate levels of vascular endothelial growth factor (VEGF) and its soluble receptor, sFlt-1, with endothelial function in healthy smokers. Methods Plasma levels of VEGF and sFlt-1 were measured by ELISA in 22 healthy smokers and 22 matched healthy non-smoking controls, and compared to flow- (FMD) and acetylcholine-mediated (AMD) vasodilatation (endothelial-dependent) (EDV) and nitroglycerine-mediated (NMD) vasodilatation (endothelial-independent) of lower extremities were measured with plethysmography. Results Smokers and controls had similar plasma VEGF levels, but sFlt-1 levels were lower in smokers than in controls (p<0.01). AMD was lower in smokers compared to controls (p<0.05), but FMD and NMD levels were similar. Smokers and controls with high AMD (>12 ml/100 ml tissue/min) had significantly lower plasma VEGF levels (p<0.001). An inverse correlation was found in both groups, between VEGF and AMD (smokers: r=−0.6, p<0.01; controls: r=−0.71, p<0.005) and with FMD (smokers: r=−0.56, p<0.05; controls: r=−0.58, p<0.005). There were no significant correlations between sFlt-1 with VEGF levels or endothelial-dependent dilatation. Conclusion In conclusion, healthy smokers demonstrate abnormal AMD, and an inverse correlation between plasma VEGF levels (but not sFlt-1) with indices of endothelial dysfunction (FMD and AMD) exists. VEGF, and not sFlt-1, may be related to the pathogenesis of endothelial dysfunction in healthy smoking individuals.