The level of circulating endothelial progenitor cell is associated with cerebral vasoreactivity: a pilot study

Endothelial progenitor cell is known to be able to repair injured vessels. We assessed the hypothesis that endothelial progenitor cell also modulates cerebral endothelial function in healthy status. We used transcranial color-coded sonography to measure middle cerebral arterial vasoreactivity to CO2 (breath-holding index) in healthy subjects and observed its relationship with the number of circulating CD34CD133+ cells. To detect significant correlations between each characteristic and breath-holding index of middle cerebral artery, we used univariate and multivariate regression analyses. 22 young healthy subjects were included in the present study (6 men, 16 women; mean age: 28.45 ± 3.98 years, range: 22-34 years). The mean breath-holding index and CD45(low)CD34+CD133+ cells number were 0.95 ± 0.48% and 0.52 ± 0.26, respectively. The level of CD34CD133+ cells was independently associated with middle cerebral artery's vasoreactivity (r = 0.439, P = 0.04). Our results suggest that endothelial progenitor cell also modulates healthy cerebral vessels' endothelial function. This ability of endothelial progenitor cell could be potentially applied therapeutically and for prevention in conditions with cerebral endothelial dysfunction and cerebral ischemia.