Circulating CD34+ and CD34+VEGFR2+ progenitor cells are associated with KLOTHO KL-VS polymorphism.

ABSTRACT

BACKGROUND: KLOTHO is a regulator of endothelial cells activity and integrity. It has been described for the first time because of its anti-aging properties. KLOTHO encoding gene is present in many functional variants in humans, including "KL-VS" variant that has been connected with longevity and cardiovascular disease development. Few mechanisms have been proposed to explain these associations, but none of them focused on cells from CD34+ population. The aim of our study was to investigate influence of KLOTHO KL-VS polymorphism on populations of CD34+ and CD34+VEGFR2+ cells. METHODS AND RESULTS: We examined 167 Polish subjects from Pomeranian region. The analysis concerned KL-VS polymorphism, flow cytometry evaluation of whole blood cells and determination of endothelium-associated serum/plasma factors. Our results indicate that individuals possessing at least one KL-VS allele are characterized by greater number of CD34+ and CD34+VEGFR2+ and their various subpopulations (CD34+CD133+, CD34+c-Kit+, CD34+CXCR4+ and CD34+VEGFR2+c-Kit+) than wild-type volunteers. This group also exhibited more favorable lipid profile and statistically insignificant decrease of vWF and angiotensin II in their blood, whereas VEGF levels were elevated. CONCLUSION: One of the mechanisms that are responsible for previously described KL-VS heterozygote advantage may be connected with maintaining greater size of hematopoietic and endothelial progenitor cells population.