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Cumulus cells steroidogenesis is influenced by the degree of oocyte maturation

BACKGROUND: The possibility to predict the ability of a germ cell to properly sustain embryo development in vitro or in vivo as early as possible is undoubtedly the main problem of reproductive technologies. To date, only the achievement of nuclear maturation and cumulus expansion is feasible, as al...

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Autores principales: Lucidi, Pia, Bernabò, Nicola, Turriani, Maura, Barboni, Barbara, Mattioli, Mauro
Formato: Texto
Lenguaje:English
Publicado: BioMed Central 2003
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC161805/
https://www.ncbi.nlm.nih.gov/pubmed/12809557
http://dx.doi.org/10.1186/1477-7827-1-45
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author Lucidi, Pia
Bernabò, Nicola
Turriani, Maura
Barboni, Barbara
Mattioli, Mauro
author_facet Lucidi, Pia
Bernabò, Nicola
Turriani, Maura
Barboni, Barbara
Mattioli, Mauro
author_sort Lucidi, Pia
collection PubMed
description BACKGROUND: The possibility to predict the ability of a germ cell to properly sustain embryo development in vitro or in vivo as early as possible is undoubtedly the main problem of reproductive technologies. To date, only the achievement of nuclear maturation and cumulus expansion is feasible, as all the studies on cytoplasmic maturation are too invasive and have been complicated by the death of the cells analyzed. The authors studied the possibility to test the cytoplasmic quality of pig oocytes by evaluating their ability to produce steroidogenesis enabling factor(s). To this aim, oocytes matured under different culture conditions that allowed to obtain gradable level of cytoplasmic maturation, were used to produce conditioned media (OCM). The secretion of the factor(s) in conditioned media was then recorded by evaluating the ability of the spent media to direct granulosa cells (GC) steroidogenesis. METHODS: In order to obtain germ cells characterized by a different degree of developmental competence, selected pig oocytes from prepubertal gilts ovaries were cultured under different IVM protocols; part of the matured oocytes were used to produce OCM, while those remaining were submitted to in vitro fertilization trials to confirm their ability to sustain male pronuclear decondensation. The OCM collected were finally used on cumulus cells grown as monolayers for 5 days. The demonstration that oocytes secreted factor(s) can influence GC steroidogenesis in the pig was confirmed in our lab by studying E(2 )and P(4 )production by cumulus cells monolayers using a radioimmunoassay technique. RESULTS: Monolayers obtained by growing GC surrounding the oocytes for five days represent a tool, which is practical, stable and available in most laboratories; by using this bioassay, we detected the antiluteal effect of immature oocytes, and for the first time, demonstrated that properly matured germ cells are able to direct cumulus cells steroidogenesis by inhibiting E(2 )production (P < 0.01). Nevertheless, only fully competent oocytes were able to suppress estrogens production, while those cultured under unfavourable conditions were unable to exert any inhibitory effect on the functions of cumulus cells (P < 0.01). CONCLUSION: These results demonstrated that good quality oocytes can be easily selected on the basis of their ability to affect granulosa cell steroidogenesis thus reducing failures in reproductive technologies due to the transfer of fertilized oocytes with a scarce ability to sustain embryo development.
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spelling pubmed-1618052003-06-20 Cumulus cells steroidogenesis is influenced by the degree of oocyte maturation Lucidi, Pia Bernabò, Nicola Turriani, Maura Barboni, Barbara Mattioli, Mauro Reprod Biol Endocrinol Research BACKGROUND: The possibility to predict the ability of a germ cell to properly sustain embryo development in vitro or in vivo as early as possible is undoubtedly the main problem of reproductive technologies. To date, only the achievement of nuclear maturation and cumulus expansion is feasible, as all the studies on cytoplasmic maturation are too invasive and have been complicated by the death of the cells analyzed. The authors studied the possibility to test the cytoplasmic quality of pig oocytes by evaluating their ability to produce steroidogenesis enabling factor(s). To this aim, oocytes matured under different culture conditions that allowed to obtain gradable level of cytoplasmic maturation, were used to produce conditioned media (OCM). The secretion of the factor(s) in conditioned media was then recorded by evaluating the ability of the spent media to direct granulosa cells (GC) steroidogenesis. METHODS: In order to obtain germ cells characterized by a different degree of developmental competence, selected pig oocytes from prepubertal gilts ovaries were cultured under different IVM protocols; part of the matured oocytes were used to produce OCM, while those remaining were submitted to in vitro fertilization trials to confirm their ability to sustain male pronuclear decondensation. The OCM collected were finally used on cumulus cells grown as monolayers for 5 days. The demonstration that oocytes secreted factor(s) can influence GC steroidogenesis in the pig was confirmed in our lab by studying E(2 )and P(4 )production by cumulus cells monolayers using a radioimmunoassay technique. RESULTS: Monolayers obtained by growing GC surrounding the oocytes for five days represent a tool, which is practical, stable and available in most laboratories; by using this bioassay, we detected the antiluteal effect of immature oocytes, and for the first time, demonstrated that properly matured germ cells are able to direct cumulus cells steroidogenesis by inhibiting E(2 )production (P < 0.01). Nevertheless, only fully competent oocytes were able to suppress estrogens production, while those cultured under unfavourable conditions were unable to exert any inhibitory effect on the functions of cumulus cells (P < 0.01). CONCLUSION: These results demonstrated that good quality oocytes can be easily selected on the basis of their ability to affect granulosa cell steroidogenesis thus reducing failures in reproductive technologies due to the transfer of fertilized oocytes with a scarce ability to sustain embryo development. BioMed Central 2003-05-28 /pmc/articles/PMC161805/ /pubmed/12809557 http://dx.doi.org/10.1186/1477-7827-1-45 Text en Copyright © 2003 Lucidi et al; licensee BioMed Central Ltd. This is an Open Access article: verbatim copying and redistribution of this article are permitted in all media for any purpose, provided this notice is preserved along with the article's original URL.
spellingShingle Research
Lucidi, Pia
Bernabò, Nicola
Turriani, Maura
Barboni, Barbara
Mattioli, Mauro
Cumulus cells steroidogenesis is influenced by the degree of oocyte maturation
title Cumulus cells steroidogenesis is influenced by the degree of oocyte maturation
title_full Cumulus cells steroidogenesis is influenced by the degree of oocyte maturation
title_fullStr Cumulus cells steroidogenesis is influenced by the degree of oocyte maturation
title_full_unstemmed Cumulus cells steroidogenesis is influenced by the degree of oocyte maturation
title_short Cumulus cells steroidogenesis is influenced by the degree of oocyte maturation
title_sort cumulus cells steroidogenesis is influenced by the degree of oocyte maturation
topic Research
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC161805/
https://www.ncbi.nlm.nih.gov/pubmed/12809557
http://dx.doi.org/10.1186/1477-7827-1-45
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