Fibroblast Growth Factor Receptors (FGFRs) in human male germ cells: evidence for their expression, functionality and involvement in sperm motility regulation

SAUCEDO L; BUFFA GN; ROSSO, M; GUILLARDOY T; GONGORA A; MUNUCE, MARÍA JOSÉ; VAZQUEZ LEVIN, M; MARIN BRIGGILER, CI

PLOS ONE

PUBLIC LIBRARY SCIENCE

Lugar: San Francisco; Año: 2015 vol. 10

1932-6203

Fibroblast growth factors receptors (FGFRs) have been widely characterized in somatic cells, butthere is scarce evidence of their expression and function in mammalian gametes.The objective of the present study was to evaluate the expression of FGFRs inhuman male germ cells, to determine sperm FGFR activation by the FGF2 ligand andtheir participation in the regulation of sperm motility. The expression ofFGFR1, 2, 3 and 4 mRNAs and proteins in human testis and localization of thesereceptors in germ cells of the seminiferous epithelium was demonstrated. Inejaculated sperm, FGFRs were localized to the acrosomal region and flagellum.Sperm exposure to FGF2 caused an increase in flagellar FGFR phosphorylation andactivation of extracellular signal-regulatedkinase (ERK) and protein kinase B (PKB or Akt) signaling pathways.Incubation with FGF2 led to a significant increase in the percentage of totaland progressive sperm motility, as well as in sperm kinematics. All responseswere prevented by sperm preincubation with BGJ398, a specific inhibitor of FGFRtyrosine kinase activity. In addition to confirming the expression of FGFRs in germ cells of the human testis, ourstudy describes for the first time thepresence, localization and functionality of human sperm FGFRs, andprovides evidence of the beneficial effect of FGF2 upon sperm motility.