Effects of human oviductal in vitro secretion on spermatozoa and search of sperm-oviductal proteins interactions.

It has been suggested that oviductal proteins could be involved in modulating sperm function and fertilizing ability through as yet not well-known mechanisms. The objective of the study was to investigate the pattern of proteins secreted by human oviductal tissue cultures and the effects of their conditioned media (CM) on sperm function under capacitating conditions and in phosphate buffered saline (PBS). In addition, interactions between spermatozoa and oviductal proteins were examined. The oviductal tissue was obtained from pre-menopausal patients scheduled for hysterectomies because of uterine fibromyoma. Normozoospermic semen samples were obtained from healthy donors. Cultures of human fallopian tissue were carried out and CM were collected for analysis of the de novo production of [35S]-methionine-labelled proteins by SDS-PAGE. Motile spermatozoa were incubated under capacitating conditions and in PBS, with or without CM, and sperm fertilizing ability was assessed by ionophore-induced acrosome reaction (AR) and the acrosome reaction to ionophore challenge (ARIC) score. The ionophore-induced AR was evaluated by the Pisum sativum technique. Sixteen de novo produced proteins were detected in CM. One of these proteins (molecular weight 79 kDa) was detected in extracts from spermatozoa pre-incubated with CM. Sperm survival and motility were maintained in the presence of CM, although results showed a significant decrease in ARIC score (p < 0.05), with respect to controls. The presence of CM significantly decreased sperm fertilizing ability, without affecting sperm survival. These results suggest that the oviductal secretion could contribute to preserve sperm viability and motility, and to prevent a premature response of spermatozoa to AR inducers.

Modulation of human sperm function by peritoneal fluid.

OBJECTIVE: To examine the effect of peritoneal fluid on various parameters of sperm function in vitro. DESIGN: Prospective study. SETTING: Basic research laboratory. PATIENT(S): Semen samples were obtained from normozoospermic volunteers (n = 43). Peritoneal fluids were aspirated laparoscopically from women with unexplained infertility (n = 14). Follicular fluid and oocytes were collected from patients undergoing IVF-ET. INTERVENTION(S): Sperm incubated under capacitating conditions were exposed to peritoneal fluid, and functional variables were evaluated in vitro. MAIN OUTCOME MEASURE(S): Sperm viability and motility, follicular fluid and calcium ionophore-induced acrosome reactions, protein tyrosine phosphorylation, expression of D-mannose binding sites, and ability of sperm to interact with zona pellucida. RESULT(S): Exposure of sperm to peritoneal fluid for up to 6 hours did not affect sperm viability or motility. Unlike follicular fluid, peritoneal fluid did not induce the acrosome reaction. Moreover, incubation of sperm with > or =20% v/v peritoneal fluid for 1 hour prevented the follicular fluid and the ionophore-induced acrosome reaction. Although treatment with peritoneal fluid allowed protein tyrosine phosphorylation during capacitation, it resulted in a significant decrease in the expression of D-mannose binding sites and sperm-zona pellucida binding. CONCLUSION(S): Peritoneal fluid maintains sperm survival and decreases sperm ability to respond to inducers of the acrosome reaction and bind to the zona pellucida in vitro, indicating that this fluid might modulate sperm function in vivo.

Efecto modulador de las secreciones del tracto reproductivo femenino sobre la función del espermatozoide humano / Modulating effect of the secretions of the feminine reproductive tract on the function of the human spermatozoa

El objetivo de éste trabajo fue determinar mediante un modelo in vitro, el efecto que ejerce el fluido peritoneal sobre la función del espermatozoide humano, tomando como control al fluido folicular. Para ello se obtuvieron fluidos peritoneales provenientes de pacientes que realizaron laparascopia diagnóstica en fecha periovulatoria y que no presentaron enfermedad tubo-peritoneal (n=9). El fluido folicular se obtuvo de pacientes que realizaron recuperación ovocitaria en un programa de fertilización in vitro (n=4). Ambos fluidos fueron centrifugados, filtrados y congelados a -20§C. Los sémenes de pacientes normozoospérmicos (n=21) fueron procesados mediante un gradiente discontínuo de Percoll y capacitados en medio sintético Human Tubal Fluid suplementado con albúmina, a una concentración de 2-10 por 10 esp./ml durante 3 a 4 horas. En experimentos apareados, los espermatozoides capacitados fueron expuestos en relación 1:1 v/v al medio control, al fluido folicular o al peritoneal durante 1 hora, luego de lo cual se procedió a estudiar la función espermática mediante los siguientes tests: a) viabilidad b) motilidad progresiva c) la reacción acrosomal inducida por ionóforo de calcio y d) la expresión del receptor espermático para D-manosa. Nuestros resultados muestran que ni la viabilidad ni la motilidad resultaron afectadas por el pre-tratamiento. Si bien la ocurrencia de la reacción acrosomal espontánea no fue diferente entre los distintos grupos (6.3 a 7.5 por ciento, NS), la inducida por ionóforo disminuyó significativamente luego de la exposición al fluido peritoneal y al folicular (18.9ñ5.1 por ciento y 29.0ñ6.1 por ciento vs control 45.6ñ5.0 por ciento, p <0.001 y 0.01 respectivamente). Si bien la detección del receptor para D-manosa aumentó durante la capacitación, resultó significativamente menor a los controles luego del tratamiento previo (FP: 15.4ñ2.9 por ciento y FF: 15.5ñ3.1 por ciento vs control 23.7ñ3.1 por ciento, p<0.05. Nuestros resultados sugieren que al menos in vitro, tanto el fluido peritoneal como el folicular modularían la función del espermatozoide humano manteniéndolo vivo y móvil, pero en un estado no reaccionado

Efecto modulador de las secreciones del tracto reproductivo femenino sobre la función del espermatozoide humano / Modulating effect of the secretions of the feminine reproductive tract on the function of the human spermatozoa

El objetivo de éste trabajo fue determinar mediante un modelo in vitro, el efecto que ejerce el fluido peritoneal sobre la función del espermatozoide humano, tomando como control al fluido folicular. Para ello se obtuvieron fluidos peritoneales provenientes de pacientes que realizaron laparascopia diagnóstica en fecha periovulatoria y que no presentaron enfermedad tubo-peritoneal (n=9). El fluido folicular se obtuvo de pacientes que realizaron recuperación ovocitaria en un programa de fertilización in vitro (n=4). Ambos fluidos fueron centrifugados, filtrados y congelados a -20ºC. Los sémenes de pacientes normozoospérmicos (n=21) fueron procesados mediante un gradiente discontínuo de Percoll y capacitados en medio sintético Human Tubal Fluid suplementado con albúmina, a una concentración de 2-10 por 10 esp./ml durante 3 a 4 hora