In Vivo and In Vitro Environmental Effects on Mammalian Oocyte Quality

2013 ◽  
Vol 1 (1) ◽  
pp. 393-417 ◽  
Author(s):  
Rebecca L. Krisher
2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Salvatore Giovanni Vitale ◽  
Paola Rossetti ◽  
Francesco Corrado ◽  
Agnese Maria Chiara Rapisarda ◽  
Sandro La Vignera ◽  
...  

Assisted reproductive technologies (ART) have experienced growing interest from infertile patients seeking to become pregnant. The quality of oocytes plays a pivotal role in determining ART outcomes. Although many authors have studied how supplementation therapy may affect this important parameter for both in vivo and in vitro models, data are not yet robust enough to support firm conclusions. Regarding this last point, in this review our objective has been to evaluate the state of the art regarding supplementation with melatonin and myo-inositol in order to improve oocyte quality during ART. On the one hand, the antioxidant effect of melatonin is well known as being useful during ovulation and oocyte incubation, two occasions with a high level of oxidative stress. On the other hand, myo-inositol is important in cellular structure and in cellular signaling pathways. Our analysis suggests that the use of these two molecules may significantly improve the quality of oocytes and the quality of embryos: melatonin seems to raise the fertilization rate, and myo-inositol improves the pregnancy rate, although all published studies do not fully agree with these conclusions. However, previous studies have demonstrated that cotreatment improves these results compared with melatonin alone or myo-inositol alone. We recommend that further studies be performed in order to confirm these positive outcomes in routine ART treatment.


2014 ◽  
Vol 26 (1) ◽  
pp. 115 ◽  
Author(s):  
A. F. González-Serrano ◽  
C. R. Ferreira ◽  
V. Pirro ◽  
J. Heinzmann ◽  
K.-G. Hadeler ◽  
...  

Information on how supplementation of high-yield dairy cows with rumen-protected fat affects fertility in cattle herds is scarce. Here, Holstein-Friesian heifers (n = 84) received a supplement consisting of either rumen-protected conjugated linoleic acid (CLA; cis-9,trans-11-CLA and trans-10,cis-12-CLA) or stearic acid 18 : 0 (SA) on top of an isocaloric grass silage diet. Two supplementation doses were used (100 and 200 g d–1). Blood and follicular fluid were collected at the start and end of the supplementation period for analysis of cholesterol, insulin-like growth factor (IGF), and nonesterified fatty acids (NEFA), and for fatty acid profiling. Although cholesterol, IGF, and NEFA levels did not differ among experimental groups, lipid profiles in blood and follicular fluid were affected in a dose-dependent manner by both supplements. After 45 days of supplementation, oocytes were collected by ovum pick-up (OPU). The mRNA relative abundance of target genes (IGF1r, GJA1, FASN, SREBP1, and SCAP) was analysed in single in vitro- (24 h IVM) and in vivo-matured (collected by OPU 20 h after GnRH injection) oocytes and in vitro-produced blastocysts (Day 8) by qPCR (n = 6/group). Lipid profiling of individual oocytes from the CLA-supplemented (n = 37) and the SA-supplemented (n = 50) was performed by desorption electrospray ionization mass spectrometry (DESI-MS). Oocytes from the CLA-supplemented (n = 413) and the SA-supplemented (n = 350) groups were used for assessing maturation and blastocysts development rates. In immature oocytes, CLA supplementation led to an increase of triacylglycerol 52 : 3 [TAG (52 : 3)] and TAG (52 : 2), squalene, palmitic acid 16 : 0, and oleic acid 18 : 1, and decreased abundance of TAG (56 : 3), TAG (50 : 2) and TAG (48 : 1). In vitro-matured oocytes showed different lipid profiles, with increased abundances of TAG (52 : 3), and TAG (52 : 2) as well as phosphatidylinositol 34 : 1 [Plo (34 : 1)], whereas phosphatidylglycerol (34 : 1) [PG (34 : 1)] and palmitic acid 16 : 0 were less abundant in in vitro-matured oocytes. SCAP was significantly down-regulated in in vitro-matured oocytes from supplemented heifers compared with their in vivo-matured counterparts. Maturation (CLA = 74% v. SA = 67%) and blastocyst rates (CLA = 22.4% v. SA = 12.7%) were different among experimental groups. One-way ANOVA and the Tukey-Kramer test were applied for a multiple comparison of means (P-value ≤ 0.05 was considered as statistically significant). In conclusion, we demonstrate here that fatty acid monitoring along different compartments (i.e. blood system, follicular fluid, and intra-oocyte) after rumen-protected fat supplementation of dairy heifer diet reveals nutritional footprints on oocyte quality and embryo development. These results demonstrate the close relationship between nutrition and cattle herd's fertility and, at the same time, support the role of the bovine model for understanding nutritional-dependent fertility impairments.


2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
Irma Virant-Klun ◽  
Jeroen Krijgsveld

Oocytes are crucial cells for mammalian reproduction, yet the molecular principles underlying oocyte development are only partially understood. Therefore, contemporary proteomic approaches have been used increasingly to provide new insights into oocyte quality and maturation in various species such as mouse, pig, and cow. Especially, animal studies have helped in elucidating the molecular status of oocytes duringin vitromaturation and other procedures of assisted reproduction. The aim of this review is to summarize the literature on mammalian oocyte proteome and secretome research in the light of natural and assisted reproduction and on lessons to be learned for human oocytes, which have so far remained inaccessible for proteome analysis.


Zygote ◽  
2019 ◽  
Vol 27 (05) ◽  
pp. 321-328
Author(s):  
Lucas Teixeira Hax ◽  
Joao Alveiro Alvarado Rincón ◽  
Augusto Schneider ◽  
Lígia Margareth Cantarelli Pegoraro ◽  
Letícia Franco Collares ◽  
...  

SummaryAround 60–80% of oocytes maturated in vivo reached competence, while the proportion of maturation in vitro is rarely higher than 40%. In this sense, butafosfan has been used in vivo to improve metabolic condition of postpartum cows, and can represent an alternative to increase reproductive efficiency in cows. The aim of this study was to evaluate the addition of increasing doses of butafosfan during oocyte maturation in vitro on the initial embryo development in cattle. In total, 1400 cumulus–oocyte complexes (COCs) were distributed in four groups and maturated according to supplementation with increasing concentrations of butafosfan (0 mg/ml, 0.05 mg/ml, 0.1 mg/ml and 0.2 mg/ml). Then, 20 oocytes per group were collected to evaluate nuclear maturation and gene expression on cumulus cells and oocytes and the remaining oocytes were inseminated and cultured until day 7, when blastocysts were collected for gene expression analysis. A dose-dependent effect of butafosfan was observed, with decrease of cleavage rate and embryo development with higher doses. No difference between groups was observed in maturation rate and expression of genes related to oocyte quality. Our results suggest that butafosfan is prejudicial for oocytes, compromising cleavage and embryo development.


2011 ◽  
Vol 23 (6) ◽  
pp. 788 ◽  
Author(s):  
D. R. Li ◽  
G. S. Qin ◽  
Y. M. Wei ◽  
F. H. Lu ◽  
Q. S. Huang ◽  
...  

This study was carried out to test the feasibility of enhancing embryo production in vivo and in vitro by immunoneutralisation against inhibin or follistatin. In Experiment 1, multi-parity buffaloes were assigned into three groups: High group (n = 8), which received one primary (2 mg) and two booster (1 mg) vaccinations (28-day intervals) with a recombinant inhibin α subunit in 1 mL of white oil adjuvant; Low group (n = 8), which received half that dose; and Control group (n = 7), which received only adjuvant. Immunisation against inhibin stimulated development of ovarian follicles. Following superovulation and artificial insemination, inhibin-immunised buffaloes had more developing follicles than the Control buffaloes. The average number of embryos and unfertilised ova (4.5 ± 0.6, n = 6) in the High group was higher (P < 0.05) than in the Control group (2.8 ± 0.6, n = 5) and was intermediate (4.1 ± 0.7, n = 7) in the Low group. The pooled number of transferable embryos of the High and Low groups (3.2 ± 0.5, n = 13) was also higher (P < 0.05) than that (1.6 ± 0.7, n = 5) of the controls. The immunised groups also had higher plasma concentrations of activin, oestradiol and progesterone. In Experiment 2, the addition of anti-inhibin or anti-follistatin antibodies into buffalo oocyte IVM maturation medium significantly improved oocyte maturation and cleavage rates following parthenogenic activation. Treatment with anti-follistatin antibody also doubled the blastocyst yield from activated embryos. These results demonstrated that immunisation against inhibin stimulated follicular development, enhanced oocyte quality and maturation competence, yielded more and better embryos both in vivo and in vitro.


2020 ◽  
Author(s):  
Ning Tian ◽  
Dan-yu Lv ◽  
Ji Yu ◽  
Wan-yun Ma

Abstract Background:Methotrexate (MTX) is an antifolate agent which is widely used in clinic for treating malignancies, rheumatoid arthritis and ectopic pregnancy. As reported, MTX has side effects on gastrointestinal system, nervous system and reproductive system, while its potential damages on oocyte quality are still unclear. It is known that oocyte quality is essential for healthy conception and the forthcoming embryo development. Thus, this work studied the effects of MTX on the oocyte quality. Results: We established MTX model mice by single treatment with 5 mg/Kg MTX. Both morphological and molecular biology studies were performed to assess the in-vivo matured oocytes quality and to analyze the related mechanisms. The in-vivo matured oocytes from MTX-treated mice had poor in-vitro fertilization ability, and the resulting embryo formation rates and blastocyst quality were lower than the control group. We found that the in-vivo matured MTX-treated mouse oocytes displayed abnormal transcript expressions for genes of key enzymes in the folate cycles. MTX increased the rate of abnormal chromosome alignment and affected the regulation of chromosome separation via disrupting the spindle morphology and reducing the mRNA expressions of MAD2 and Sgo1. MTX reduced the DNA methylation levels in the in-vivo matured oocytes, and further studies showed that MTX altered the expressions of DNMT1 and DNMT 3b, and may also affect the levels of the methyl donor and its metabolite. Conclusions: MTX impaired the in-vivo matured mouse oocyte quality by disturbing folate metabolism and affecting chromosome stability and methylation modification.


2021 ◽  
Author(s):  
◽  
Kelly Anne Campen

<p>Pathways involved in bi-directional communication within the cumulus-oocyte complex (COC) include gap junction (GJ) communication, oocyte growth factor production, and glucose metabolism and are essential for oocyte health. Perturbation of these pathways may result in reduced oocyte quality due to altered COC function. Using rats as a model, in vitro effects of exposure to bisphenol A (BPA), caffeine, nicotine, ethanol, methylenedioxymeth- amphetamine (MDMA), or Δ⁹-tetrahydrocannabinol (THC) on COC function were investigated. Furthermore, MDMA was administered to rats to compare in vitro with in vivo effects.  The transfer of a fluorescent dye (calcein) from cumulus cells (CC) to the oocyte was used as a measure of GJ communication. Expression of CC-derived (Atr, Cx43, Cycs, Gfpt1, Pfkp) and oocyte-derived (Atr, Bmp15, Cx37, Gdf9) genes were measured using multiplex TaqMan quantitative PCR. Levels of CX43 and GDF9 proteins were quantified using Western blotting.  Optimisation of the GJ bioassay included the addition of phosphodiesterase inhibitors (rolipram and dipyridamole), and a 1 hour post-calcein incubation period to allow dye transfer. Quantification of gene expression in calcein-treated CC and oocytes was validated, enabling direct comparisons between GJ communication and gene expression.  To determine the in vitro effects, COC were incubated with test factors at high physiological concentrations over 25 hours. GJ communication decreased over time in control COC. This reduction was attenuated after exposure to BPA and nicotine, and partially by caffeine. Furthermore, exposure to ethanol maintained oocyte meiotic arrest, whereas MDMA and THC promoted meiotic resumption.  Oocyte-derived gene expression was mostly unaffected by in vitro exposure to the lifestyle and environmental factors, although a treatment x time interaction for Cx37 levels following nicotine exposure was observed. Of the CC-derived genes, Cx43 was the most sensitive where BPA, MDMA, and THC increased, and caffeine and ethanol decreased, expression. In CC, exposure to MDMA and THC increased Gfpt1 levels and exposure to MDMA resulted in a treatment x time interaction in Cycs and Pfkp expression.  In COC, caffeine increased CX43 protein levels after 1 hour. Nicotine initially reduced, but with time increased CX43 levels. Furthermore, CX43 levels decreased and increased after 25 hour exposures to ethanol and MDMA, respectively. GDF9 protein levels in COC exhibited wide within-treatment variation. Overall, BPA and caffeine reduced GDF9 levels after 1 hour whereas GDF9 levels were increased following exposure to BPA, caffeine, MDMA, and THC for 25 hours.  To determine in vivo effects, female rats were administered saline or 5 mg/kg/day MDMA for 3 days. COC from MDMA-treated rats had higher levels of CX43 protein but gene expression and meiotic reactivation were unaffected.  In conclusion, COC function was altered by in vitro exposure to BPA, caffeine, ethanol, nicotine, MDMA, and THC. Furthermore, in vivo exposure to MDMA elicits similar, albeit reduced, effects on COC function. A role for CC in protecting the oocyte from harmful contaminants is proposed. Perturbation of the bi-directional communication pathway is likely to influence oocyte quality due to alterations in nutrient availability and timing of follicular events, although these may not be associated with negative outcomes. This study provides evidence that exposure to lifestyle factors and environmental contaminants affect COC function.</p>


2008 ◽  
Vol 20 (9) ◽  
pp. 108
Author(s):  
K. R. Dunning ◽  
L. K. Akison ◽  
D. L. Russell ◽  
R. J. Norman ◽  
R. L. Robker

In vivo, the oocyte matures in a niche environment surrounded by somatic cells, and later in ovarian follicular development, by follicular fluid. Maternal diet influences the environment in which an oocyte matures but the mechanisms by which an altered metabolic profile, such as hyperinsulinemia, affects oocyte quality are not known. We investigated the use of a three dimensional follicle culture system allowing direct manipulation of the follicular environment thus circumventing systemic hormonal and metabolic effects. Secondary follicles (113.4 ± 1.02µm, n = 54) were isolated from mice at d12, encapsulated individually in 2µl of alginate matrix, and cultured in aMEM/5%FCS/10 mIU/mL LH/100 mIU FSH at 37°C/5%CO2, with media sampling and replacement every second day. Following 12 days of culture there was a significant 3-fold increase in follicle diameter (320 ± 10.1µm, n = 51). Histological analysis showed normal follicular morphology and antrum formation. Analysis of oestradiol (15.0ng/mL), androstenedione (7.8ng/mL) and progesterone (23.7ng/mL) in the media at d12 confirmed normal steroidogenesis and differentiation. Treatment of follicles with an ovulatory stimulus (1.5IU/mL hCG/5ng/mL Egf), resulted in cumulus expansion and hyaluronan localising to the cumulus oocyte complex (COC) and follicular basement membrane. These analyses were consistent with follicle growth and induction of ovulation in vivo. Further, COCs isolated from follicles and matured in vitro (IVM) in the presence of Egf and FSH, underwent cumulus expansion (CEI 2.8 ± 0.2) and were capable of fertilisation and blastocyst development. LH did not induce IVM COC expansion (CEI 1.36 ± 0.2), reflecting the normal in vivo differentiation process. However, culturing follicles in high insulin (5ug/mL) led to a significant increase in the degree of IVM cumulus expansion in response to LH (CEI 2.1 ± 0.3) indicating inappropriate cumulus cell differentiation, which may lead to poorer oocyte quality. These results demonstrate that this technique recapitulates normal in vivo folliculogenesis and is useful for manipulation of the follicular environment and assessment of oocyte outcomes.


2012 ◽  
Vol 302 (12) ◽  
pp. E1511-E1518 ◽  
Author(s):  
Qiang Wang ◽  
Maggie M. Chi ◽  
Tim Schedl ◽  
Kelle H. Moley

Glucose is an essential nutrient for mammalian cells. Emerging evidence suggests that glucose within the oocyte regulates meiotic maturation. However, it remains controversial as to whether, and if so how, glucose enters oocytes within cumulus-oocyte complexes (COCs). We used a fluorescent glucose derivative (6-NBDG) to trace glucose transport within live mouse COCs and employed inhibitors of glucose transporters (GLUTs) and gap junction proteins to examine their distinct roles in glucose uptake by cumulus cells and the oocyte. We showed that fluorescent glucose enters both cumulus-enclosed and denuded oocytes. Treating COCs with GLUT inhibitors leads to simultaneous decreases in glucose uptake in cumulus cells and the surrounded oocyte but no effect on denuded oocytes. Pharmacological blockade of of gap junctions between the oocyte and cumulus cells significantly inhibited fluorescent glucose transport to oocytes. Moreover, we find that both in vivo hyperglycemic environment and in vitro high-glucose culture increase free glucose levels in oocytes via gap junctional channels. These findings reveal an intercellular pathway for glucose transport into oocytes: glucose is taken up by cumulus cells via the GLUT system and then transferred into the oocyte through gap junctions. This intercellular pathway may partly mediate the effects of high-glucose condition on oocyte quality.


Sign in / Sign up

Export Citation Format

Share Document