[Investigation of mechanisms of action of growth factors of autologous platelet-rich plasma used to treat erectile dysfunction]

Abstract

Aim: To determine the quantitative and qualitative composition of growth factors (PDGF-AA, PDGF-BB, VEGF, VEGF-D, FGF-acid, FGF-basic) and platelets in various modifications of APRP.

Materials and methods: Blood of 12 male volunteers (control group) and 12 patients with ED was used to prepare APRP and the subsequently determine the concentration of growth factors. The growth factor concentrations (FGF acid, FGF basic, PDGF-AA, PDGF-BB, VEGF, VEGF-D) was determined using a flow cytometry-based xMAP Luminex (Gen-Probe) system.

Results: Concentration of platelets in APRP obtained by two stage centrifugation, reached 1480 (1120-1644) in the control group and 1232 (956-1502) in patients with ED. The concentration of growth factors in the samples prepared without preliminary freezing was: PDGF-AA 842 (22-3700), PDGF-BB 2837 (1460-4100), FGF-basic 7.9 (0.28-127), FGF-acid 3, 4 (0.14-11), VEGF 19 (4.6-46), VEGF-D 21 (14-38). After thawing, the concentration of all growth factors in the samples increased.

Discussion: The study findings suggest that the mechanism of erectile function recovery following the use of APRP is through the active substances detected in APRP, i.e. FGF-basic, PDGF-AA, PDGF-BB, VEGF, VEGF-D and FGF-acid. Also, the study showed that the content of growth factors in APRP after of freezing/thawing is higher than in APRP that has not been frozen. This is due to the cell membrane destruction at extremely low temperatures during freezing.

Keywords: FGF (fibroblast growth factor); PGF (platelet growth factor); VEGF (vascular endothelial growth factor); autologous platelet-rich plasma (APRP); cryopreservation; erectile dysfunction (ED); growth factors.