The inhibition of the human sperm phosphatidylinosytol 3-kinase by LY294002 does not interfere with sperm/oocyte interaction.

It has recently been reported that the selective inhibition of phosphatidylinosytol 3-kinase (PI3K) enhances human sperm motility. However, little information exists on a possible role of PI3K in other sperm functions involved in the fertilization process. In this study, we investigated whether LY294002 could affect human sperm ability to fuse with oocytes, by means of the hamster egg penetration test (HEPT). The effect on acrosome reactions (AR) and on sperm/zona pellucida (ZP) binding was also evaluated. The pre-incubation with scalar doses of LY294002 (0.1, 1 and 10 microm) did not interfere with sperm ability to fuse with oocytes either in the conventional version of the HEPT or in the version enhanced with progesterone (P). No interference with the stimulatory effect on AR exerted by P or mannose-bovine serum albumin (mannose-BSA) was revealed. Finally, LY294002 had no effect on sperm/ZP binding. These results indicate that the inhibition of PI3K by LY294002 does not interfere with sperm interaction with oocytes. This is noteworthy in the view of a possible clinical use of LY294002 as an in vitro stimulator of the sperm motility of asthenozoospermic patients for assisted reproduction techniques.

Monoclonal antibody c262 counteracts the stimulatory effect of progesterone on sperm-oocyte fusion.

Some evidence suggests that the non-genomic effects exerted by progesterone (P) on human spermatozoa are mediated by membrane receptor(s) displaying the C-terminal domain, but not the N-terminal domain of the genomic P receptor (PR). This study aimed at determining whether the monoclonal antibody (mAb) c-262, directed against the C-terminal domain of the genomic PR, counteracts the stimulatory effect of P on the human sperm ability to fuse with oocytes. Sperm/oocyte fusion was evaluated by means of the hamster egg penetration test. The brief exposure of capacitated spermatozoa to P produced a stimulatory effect on sperm/oocyte fusion. mAb c262 counteracted this stimulatory effect in a dose-dependent manner. No counteraction was observed when capacitated spermatozoa were pre-exposed to PGR-312, a mAb directed against the N-terminal domain of the genomic PR. These results reinforce the hypothesis that the non-genomic effects exerted by P on human spermatozoa are mediated by membrane receptor(s) displaying the C-terminal domain, but not the N-terminal domain of the genomic PR.

[Action of infrared laser on in vitro culture of fibroblasts: effects of the exposure time parameter]. / Applicazione del laser infrarosso a colture in vitro di fibroblasti: effetti del parametro tempo di esposizione.

We have evaluated the effects of low dose laser radiation on in vitro grown fibroblasts. We have observed no differences between treated plates and no treated plates after modification of exposure time.

[Application of infrared lasers on in vitro culture of fibroblasts: effects of the duration of treatment parameter]. / Applicazione del laser infrarosso a colture in vitro di fibroblasti: effetti del parametro durata di trattamento.

We have evaluated the effects of low dose laser radiation on in vitro grown fibroblasts. We have seen after twelve days of plates exposure at low doses of laser radiation a remarkable increment of cellular density. We conclude that the stimulating action on cellular mitosis are directly correlated at the length of the sample treatment with I.R. laser.