51(5):1411-7; discussion 1417-9
Relationship between vascular damage degrees and endothelial progenitor cells in patients with erectile dysfunction: effect of vardenafil administration and PDE5 expression in the bone marrow.
Foresta C, Caretta N, Lana A, De Toni L, Biagioli A, Vinanzi C, Ferlin A:
OBJECTIVES: To evaluate the levels of circulating progenitor cells (PCs) and the effect of a single
dose of vardenafil 20mg on the number of these cells in men with erectile dysfunction (ED) and
various degree of vascular injury at the carotid artery level.
METHODS: Sixty-eight patients with ED and various degree of carotid damage, and 25 controls were
enrolled. Patients were divided into three groups according to their intima media thickness (IMT)
status (normal, mild increase, or plaque). All subjects received vardenafil 20mg, and evaluation of
the number of circulating PCs was performed at baseline and 4h after vardenafil administration. An
RNA expression analysis of phosphodiesterase type 5 (PDE5) on bone marrow was also performed.
RESULTS: We found a significant reduction of circulating PCs in ED patients with respect to
controls and a reduction in PC counts in patients with mild IMT increase or plaque, but not in those
with normal IMT. Four hours after vardenafil administration we observed an increase in the number
of PCs in all patients and controls. Reverse transcriptase-polymerase chain reaction analysis
showed that human bone marrow expresses PDE5 messenger RNA.
CONCLUSIONS: Patients with ED and a low number of circulating PCs may be considered at
increased risk for an endothelial dysfunction. An impaired response to vardenafil stimulus may be
proposed as a surrogate marker of a patient’s endothelial regenerative ability.
PMID: 17034932 [PubMed – indexed for MEDLINE]