scholarly journals Endocrine-disrupting chemicals in human follicular fluid impair in vitro oocyte developmental competence

2012 ◽  
Vol 27 (4) ◽  
pp. 1025-1033 ◽  
Author(s):  
Evi M.L. Petro ◽  
Jo L.M.R. Leroy ◽  
Adrian Covaci ◽  
Erik Fransen ◽  
Diane De Neubourg ◽  
...  
2007 ◽  
Vol 19 (1) ◽  
pp. 286
Author(s):  
C. G. Grupen ◽  
T. S. Hussein ◽  
S. J. Schulz ◽  
D. T. Armstrong

Supplementing medium with follicular fluid (FF) during in vitro maturation (IVM) enhances the developmental competence of porcine oocytes, indicating that factors present in FF are beneficial to cytoplasmic maturation. Previous findings suggest that porcine FF contains high levels of superoxide dismutase activity and exerts a beneficial effect on cytoplasmic maturation by protecting oocytes from oxidative stress (Tatemoto et al. 2004 Biol. Reprod. 71, 1150–1157). Since oxidative stress is a potent inducer of apoptosis, the aim of the present study was to examine the temporal effects of FF during IVM on cumulus cell apoptosis and oocyte developmental competence. Ovaries of prepubertal pigs were collected from a local abattoir and antral follicles, 3 to 7 mm in diameter, were aspirated. Cumulus–oocyte complexes (COCs) with at least 3 uniform layers of compact cumulus cells (CCs) were recovered, washed, and transferred to maturation medium (MM) with or without 25% FF. At 22 h of IVM, COCs from each group were washed and transferred to fresh MM with or without 25% FF, forming 4 groups: -FF/-FF, -FF/+FF, +FF/-FF, and +FF/+FF. Cohorts of COCs were TUNEL stained at 22 and 44 h of IVM using the In Situ Cell Death Detection kit (Roche Diagnostics, Castle Hill, NSW, Australia) according to the manufacturer's instructions, and apoptotic CCs were visualized using confocal microscopy. Oocytes denuded at 44 h, that had a polar body, were treated with ionomycin and 6-dimethylaminopurine to induce parthenogenetic development, and were cultured for 7 days in NCSU-23 medium at 38.5°C in 5% O2, 5% CO2, and 90% N2. Data were subjected to ANOVA and Tukey's post-hoc test. At 22 h of IVM, the presence of FF reduced the proportion of apoptotic CCs in COCs (2.1% vs. 4.6%). COCs matured with FF from 22 to 44 h of IVM had much lower proportions of apoptotic CCs (+FF/+FF: 0.9%; −FF/+FF: 2.6%) compared with those matured without FF (+FF/−FF: 10.3%; −FF/−FF: 17.8%). The rate of maturation to the metaphase-II stage was greater when oocytes were matured with FF from 0 to 22 h of IVM (−FF/−FF: 68.6%; −FF/+FF: 72.8%; +FF/−FF: 89.2%; +FF/+FF: 86.2%). Maturation without FF for the entire IVM interval reduced the proportion of activated oocytes that formed blastocysts compared with the other groups (−FF/−FF: 25.1%; −FF/+FF: 44.6%; +FF/−FF: 46.6%; +FF/+FF: 47.3%). Despite a 4-fold difference in the proportion of apoptotic CCs between COCs of the +FF/−FF and −FF/+FF groups, exposure to FF for the first or second half of IVM was as beneficial to oocyte developmental competence as exposure to FF for the entire IVM interval. This suggests that the protective effect of FF in reducing oxidative stress on oocytes during IVM is distinct from the effect on oocyte developmental competence.


2003 ◽  
Vol 15 (2) ◽  
pp. 81 ◽  
Author(s):  
Christopher G. Grupen ◽  
Stephen M. McIlfatrick ◽  
Rodney J. Ashman ◽  
Andrew C. Boquest ◽  
David T. Armstrong ◽  
...  

The developmental competence of oocytes recovered from the ovaries of slaughtered prepubertal and adult pigs was evaluated after in vitro maturation, parthenogenetic activation and culture in vitro. In addition, the effect of prepubertal and adult follicular fluid (FF) on the developmental competence of prepubertal and adult oocytes was investigated. When matured in adult FF, the rates of cleavage (92 v. 73%; P < 0.01) and blastocyst formation (57 v. 38%; P < 0.05) were greater for adult oocytes than for prepubertal oocytes. Blastocysts derived from adult oocytes had more trophectoderm cells (43 v. 30; P < 0.05) and total cells (51 v. 36; P < 0.05) than blastocysts derived from prepubertal oocytes. The developmental competence of prepubertal oocytes was not affected by the FF donor age, whereas the developmental competence of adult oocytes was. Blastocysts derived from adult oocytes matured in adult FF had more trophectoderm cells (38 v. 24; P < 0.005), inner cell mass cells (7 v. 3; P < 0.01) and total cells (45 v. 27; P < 0.001) than blastocysts derived from adult oocytes matured in prepubertal FF. Characterization of the steroid content of the FF used to supplement the maturation medium revealed that adult FF contained more progesterone (42 v. 23 ng mL−1; P < 0.005) and androstenedione (70 v. 16 ng mL−1; P < 0.05) than prepubertal FF. In addition, the molar ratios of progesterone to androstenedione, androstenedione to 17β-oestradiol and androstenedione to testosterone differed (P < 0.05) between prepubertal and adult FF. The results support the hypothesis that a greater proportion of adult oocytes than of prepubertal oocytes has completed ‘oocyte capacitation’. The differences in FF steroid content are indicative of the different follicular environments from which the prepubertal and adult oocytes were isolated, and may be attributed to the observed effects on oocyte developmental competence.


2019 ◽  
Vol 31 (1) ◽  
pp. 162
Author(s):  
J. E. Seccafien ◽  
J. M. Kelly ◽  
H. McGrice ◽  
D. O. Kleemann ◽  
K. L. Kind ◽  
...  

Currently, the commercial viability of assisted reproductive embryo technologies within the Australian livestock industry is restricted by individual variability in response to treatment protocols as well as oocyte developmental competence. The majority of losses come from embryo wastage, resulting from poor developmental competence during in vitro embryo production. Follicular fluid is readily available when oocytes are collected for in vitro embryo production from juvenile or mature ewes, making it an appropriate target for analysis of phenotypic markers of oocyte developmental competence. Plasma anti-Müllerian hormone (AMH) is correlated with pregnancy losses, oocyte recovery, and blastocyst development in sheep and cattle and is an indicator for donors that respond best to gonadotrophin stimulation protocols in sheep, cattle, and goats. The aim of the current work was to determine the relationship between follicular fluid AMH and in vitro embryo production outcomes in sheep. Briefly, pairs of ovaries from 38 abattoir-derived lambs were collected individually and transferred to the laboratory. Ovaries were aspirated for in vitro embryo production following previously described methods (Walker et al. 1996 Biol. Reprod. 55, 703-708) and follicles counted. Aspirated oocytes from each of the 38 individual lamb’s pair of ovaries were pooled [n=4.11±0.53 cumulus-oocyte complexes (COC) matured/lamb; total COC matured=156], and remained as such during maturation, fertilisation, and culture. The remaining follicular fluid was centrifuged for 10min at 3000 rpm to remove excess cells and frozen at −20°C. The AMH was measured in follicular fluid by a human AMH Gen II ELISA kit validated for ovine samples (A79766, Beckman Coulter, Brea, CA, USA). Correlations between follicular fluid AMH levels and oocyte maturation and blastocyst development were determined using simple linear regression. Animals were divided into groups based on AMH levels [low (0.5-10.8ng mL−1), medium (10.81-17.89ng mL−1), or high (17.9-19.25ng mL−1)], with an unbalanced ANOVA used to determine group effects on oocyte maturation and blastocyst development (GenStat 18th edition, VSN International, Hemel Hempstead, UK). Follicular fluid AMH was positively correlated (P&lt;0.05) with the number of follicles greater than 2mm (r2=0.120) and the proportion of COC cleaved from recovered oocytes (r2=0.134). The number of COC matured per lamb was greater for those with high and medium versus low AMH (5.6±0.97 and 4.4±0.72 versus 2.1±0.97 COC/lamb). Animals with high AMH produced more blastocysts than those with medium or low AMH, when expressed as a proportion of COC recovered (P&lt;0.002) or cleaved (P&lt;0.009) oocytes. High AMH was also correlated with a greater number of expanded blastocysts produced from cleaved oocytes (P&lt;0.042). The current data support previous evidence that AMH levels positively correlate to higher antral follicle counts. The correlation between AMH and components of oocyte developmental competence suggests intrafollicular AMH may indicate the best oocytes to use for an in vitro embryo production system.


2010 ◽  
Vol 22 (7) ◽  
pp. 1100 ◽  
Author(s):  
Christopher G. Grupen ◽  
David T. Armstrong

The objective of the present study was to determine the temporal effects of sow follicular fluid (FF) in vitro on cumulus cell viability and function, as well as oocyte nuclear and cytoplasmic maturation. Cumulus–oocyte complexes (COCs) recovered from the ovaries of prepubertal pigs were matured in medium with (+FF) or without (–FF) follicular fluid for the first 22 h of IVM. At 22 h of IVM, each group of COCs was then transferred to medium with or without FF and matured for another 22 h, forming four treatment groups (–FF/–FF, –FF/+FF, +FF/–FF and +FF/+FF). The concentration of progesterone in spent IVM medium and the incidence of cumulus cell apoptosis in individual COCs were determined at 22 and 44 h of IVM. Cumulus expansion was also recorded at 44 h of IVM. Finally, the ability of oocytes to complete meiosis to the MII stage and form blastocysts after IVF and embryo culture was assessed. Maturation with FF for part or the whole of IVM increased cumulus expansion and progesterone production and decreased the incidence of cumulus cell apoptosis compared with the –FF/–FF group (P < 0.05). The changes were greatest for the +FF/+FF group and intermediate for the –FF/+FF and +FF/–FF groups. Regression analysis revealed a negative association between cumulus cell progesterone production and the incidence of cumulus cell apoptosis (P < 0.001). Meiotic maturation was enhanced when FF was present during the first half of IVM. Oocytes matured in the presence of FF during the first and/or second half of IVM displayed an increased ability to form blastocysts compared with the –FF/–FF group (P < 0.05). The extent of the increase was similar for all FF-supplemented groups. The results show that FF exerts several beneficial effects at different times during IVM and suggest that a major role of FF is to provide protection from oxidative stress. We propose that the incidence of cumulus cell apoptosis in COCs must be kept below a certain threshold to ensure adequate functionality, including steroidogenic activity, is maintained for the acquisition of oocyte developmental competence.


2015 ◽  
Vol 30 (2) ◽  
pp. 203-207 ◽  
Author(s):  
Sara D.M. Valckx ◽  
Jessie De Bie ◽  
Ellen D. Michiels ◽  
Ilse G. Goovaerts ◽  
Usha Punjabi ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document