Fibronectin stimulates human sperm capacitation through the cyclic AMP/protein kinase A pathway

摘要: STUDY QUESTION Does fibronectin (Fn) stimulate the sperm capacitation process in humans? SUMMARY ANSWER Fibronectin stimulates human capacitation. WHAT IS KNOWN ALREADY Capacitation is a that occurs oviduct. It has been suggested some molecules present oviductal fluid and cells as well proteins cumulus oophorus could be involved modulation of function their acquisition fertilizing capacity. glycoprotein oviduct epithelium, its receptor (alpha 5 beta 1 integrin) sperm. When alpha (α5β1) integrin binds to fibronectin, intracellular signals similar are activated. DESIGN, SIZE, DURATION Human were selected via percoll gradient then incubated non-capacitated medium (NCM) or reconstituted capacitated (RCM), presence absence for different time periods. A total 39 donors used during study, which lasted 3 years. PARTICIPANTS/MATERIALS, SETTING, METHODS Freshly ejaculated from healthy volunteers obtained by masturbation. All semen samples normal according World Health Organization parameters. Six approaches determine effects on capacitation: chlortetracycline (CTC) assay, heterologous co-culture with bovine epithelial (BOEC), measurement cyclic (c) AMP levels, activity protein kinase (PKA), phosphorylation tyrosine (Tyr) residues, induction acrosome reaction progesterone. MAIN RESULTS AND THE ROLE OF CHANCE RCM Fn, we observed differences respect without Fn (control): (i) 10% increase percentage B pattern (capacitated sperm) CTC fluorescence beginning (P < 0.001); (ii) an effect both concentration cAMP 0.05) PKA early capacitation; (iii) degree residues after 60 min 0.01); (iv) acrosome-reacted response progesterone 0.05); (v) decrease attached BOEC 0.05). Moreover, noted was specific mediated 0.001). itself had no LIMITATIONS, REASONS FOR CAUTION This study carried out young adult men. Men abnormal excluded. The results cannot directly extrapolated other mammalian species. WIDER IMPLICATIONS FINDINGS Currently, male subfertility become huge public health problem, makes it imperative develop new treatments. novel discovery extends our current knowledge concerning pathological physiology events regulate fertilization. FUNDING/COMPETING INTERESTS supported grants FONDECYT (1130341, E.S.D. 1120056, P.M.) FONCYT (PIP 2011-0496, S.P.-M). authors have conflicts interest.