266 Effects of Inflammatory States on Ovarian Biology and Oocyte Competence

Abstract Female fertility is dependent on estradiol concentrations which regulate a multitude of ovarian functions including follicle development and oocyte maturation leading to ovulation of a viable oocyte. Estradiol biosynthesis is regulated by coordinated actions of follicle-stimulating hormone and intra-ovarian control mechanisms including the co-transcription factor beta-catenin. Beta-catenin is a multi-faceted protein recognized for its role in granulosa cell steroid production and is shown to be modulated by lipopolysaccharide (LPS), the endotoxin responsible for stimulation of the immune system in infections caused by Gram-negative bacteria. Beef heifers treated with subacute concentrations of LPS during a synchronized follicular wave demonstrate a decline in serum estradiol concentrations 50 h after CIDR withdrawal, corresponding with dominant follicle maturation and preceding ovulation. The endotoxin exposure also resulted in increased LPS concentration and E2:P4 ratios in follicular fluid suggesting that low dose LPS modulates the intra-follicular hormonal milieu. Additionally, in a granulosa cell line, LPS treatment decreased mRNA expression of aromatase and beta-catenin. These data indicate that LPS alters E2 synthesis by modulating beta-catenin and subsequent steroidogenic enzyme expression. To further explore the contribution of naturally occurring LPS exposure on follicular steroid production and developing oocytes, bovine ovary pairs were collected from local abattoirs. Oocytes were aspirated from small follicles and matured in vitro to evaluate meiotic events related to nuclear maturation and spindle morphology. Small follicles from ovarian pairs were separated by the detectable LPS concentrations into high and low LPS groups. Oocytes matured from low LPS follicles demonstrated an increase in the percent of abnormal maturation events. Data indicate that induced or naturally occurring low doses of LPS can alter circulating and follicular estradiol concentrations impairing oocyte maturation. Perturbation to local ovarian signaling cascades from subclinical inflammatory disease may be an unappreciated factor altering fertility and leading to decreased cow retention.

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Oocyte Competence Biomarkers Associated With Oocyte Maturation: A Review

Frontiers in Cell and Developmental Biology ◽

10.3389/fcell.2021.710292 ◽

2021 ◽

Vol 9 ◽

Author(s):

Batara Sirait ◽

Budi Wiweko ◽

Ahmad Aulia Jusuf ◽

Dein Iftitah ◽

R. Muharam

Keyword(s):

Oocyte Maturation ◽

Blastocyst Stage ◽

Current Approach ◽

Developmental Competence ◽

Matrix Remodeling ◽

Oocyte Competence ◽

Nuclear Maturation ◽

Oocyte Developmental Competence ◽

Cumulus Oocyte Complex

Oocyte developmental competence is one of the determining factors that influence the outcomes of an IVF cycle regarding the ability of a female gamete to reach maturation, be fertilized, and uphold an embryonic development up until the blastocyst stage. The current approach of assessing the competency of an oocyte is confined to an ambiguous and subjective oocyte morphological evaluation. Over the years, a myriad of biomarkers in the cumulus-oocyte-complex has been identified that could potentially function as molecular predictors for IVF program prognosis. This review aims to describe the predictive significance of several cumulus-oocyte complex (COC) biomarkers in evaluating oocyte developmental competence. A total of eight acclaimed cumulus biomarkers are examined in the study. RT-PCR and microarray analysis were extensively used to assess the significance of these biomarkers in foreseeing oocyte developmental competence. Notably, these biomarkers regulate vital processes associated with oocyte maturation and were found to be differentially expressed in COC encapsulating oocytes of different maturity. The biomarkers were reviewed according to the respective oocyte maturation events namely: nuclear maturation, apoptosis, and extracellular matrix remodeling, and steroid metabolism. Although substantial in vitro evidence was presented to justify the potential use of cumulus biomarkers in predicting oocyte competency and IVF outcomes, the feasibility of assessing these biomarkers as an add-on prognostic procedure in IVF is still restricted due to study challenges.

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Effect of urokinase type plasminogen activator on in vitro bovine oocyte maturation

Reproduction ◽

10.1530/rep-17-0204 ◽

2017 ◽

Vol 154 (3) ◽

pp. 331-340 ◽

Cited By ~ 1

Author(s):

Roldán-Olarte Mariela ◽

Maillo Verónica ◽

Sánchez-Calabuig María Jesús ◽

Beltrán-Breña Paula ◽

Rizos Dimitrios ◽

...

Keyword(s):

Cell Cycle ◽

Plasminogen Activator ◽

Oocyte Maturation ◽

Cell Junctions ◽

Cortical Granules ◽

Cleavage Rate ◽

Nuclear Maturation ◽

Type Plasminogen Activator ◽

Urokinase Type Plasminogen Activator

This study examines the impacts of the urokinase-type plasminogen activator (uPA) on thein vitromaturation (IVM) of bovine oocytes. Cumulus–oocyte complexes in IVM medium were treated with uPA, amiloride (an uPA inhibitor), dimethyl sulfoxide (DMSO) or left untreated (control group). After 24 h of IVM, oocytes were recovered for testing or werein vitrofertilized and cultured to the blastocyst stage. The factors examined in all groups were: (i) oocyte nuclear maturation (Hoëscht staining); (ii) oocyte cytoplasmic maturation (cortical granules, CGs, distribution assessed by LCA-FITC); (iii) oocyte and cumulus cell (CC) gene expression (RT-qPCR); and (iv) embryo development (cleavage rate and blastocyst yield). Oocytes subjected to uPA treatment showed rates of nuclear maturation and CG distribution patterns similar to controls (P > 0.05), whereas lower rates of oocyte maturation were recorded in the amiloride group (P < 0.05). Both in oocytes and CC, treatment with uPA did not affect the transcription of genes related to apoptosis, cell junctions, cell cycle or serpin protease inhibitors. In contrast, amiloride altered the expression of genes associated with cell junctions, cell cycle, oxidative stress and CC serpins. No differences were observed between the control and uPA group in cleavage rate or in blastocyst yield recorded on Days 7, 8 or 9 post-insemination. However, amiloride led to drastically reduced cleavage rate (28.5% vs 83.2%) and Day 9 embryo production (6.0% vs 21.0%) over the rates recorded for DMSO. These results indicate that the proteolytic activity of uPA is needed for successful oocyte maturation in bovine.

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Effect of Hyaluronan on Developmental Competence and Quality of Oocytes and Obtained Blastocysts fromIn VitroMaturation of Bovine Oocytes

BioMed Research International ◽

10.1155/2014/519189 ◽

2014 ◽

Vol 2014 ◽

pp. 1-8 ◽

Cited By ~ 4

Author(s):

Jolanta Opiela ◽

Joanna Romanek ◽

Daniel Lipiński ◽

Zdzisław Smorąg

Keyword(s):

Dna Fragmentation ◽

Oocyte Maturation ◽

Developmental Competence ◽

Meiotic Maturation ◽

Nuclear Maturation ◽

Significant Difference ◽

The Mean ◽

Bovine Oocytes

The objective of the present study was to evaluate the effect of hyaluronan (HA) during IVM on meiotic maturation, embryonic development, and the quality of oocytes, granulosa cells (GC), and obtained blastocysts. COCs were maturedin vitroin control medium and medium with additional 0.035% or 0.07% of exogenous HA. The meiotic maturity did not differ between the analysed groups. The best rate and the highest quality of obtained blastocysts were observed when 0.07% HA was used. A highly significant difference (P<0.001) was noted in the mean number of apoptotic nuclei per blastocyst and in the DCI between the 0.07% HA and the control blastocysts (P<0.01). Our results suggest that addition of 0.035% HA and 0.07% HA to oocyte maturation media does not affect oocyte nuclear maturation and DNA fragmentation. However, the addition of 0.07% HA during IVM decreases the level of blastocysts DNA fragmentation. Finally, our results suggest that it may be risky to increase the HA concentration during IVM above 0.07% as we found significantly higherBaxmRNA expression levels in GC cultured with 0.07% HA. The final concentration of HA being supplemented to oocyte maturation media is critical for the success of the IVP procedure.

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172 DETERMINING THE REQUIREMENTS FOR LH AND FSH DURING SHEEP IN VITRO OOCYTE MATURATION

Reproduction Fertility and Development ◽

10.1071/rdv26n1ab172 ◽

2014 ◽

Vol 26 (1) ◽

pp. 200 ◽

Cited By ~ 5

Author(s):

C. de Frutos ◽

R. Vicente-Perez ◽

P. J. Ross

Keyword(s):

Oocyte Maturation ◽

In Vitro Maturation ◽

Mixed Logit ◽

Cumulus Cells ◽

Pituitary Hormones ◽

Developmental Competence ◽

Cumulus Expansion ◽

Nuclear Maturation ◽

Grade 3

In vitro maturation (IVM) of oocytes in domestic animals is a widespread practice of research and commercial relevance. Gonadotropic hormones are typically supplemented to the IVM medium to stimulate resumption of meiosis, progression to metaphase II (MII), and oocyte developmental competence. The common use of pituitary-derived products presents 2 problems: contamination from other pituitary hormones and inconsistences from batch-to-batch variation. Recombinant hormones can help circumvent these issues and identify specific gonadotropin requirements for in vitro maturation. The aim of the present study was to determine the effect of supplementing recombinant bovine LH and/or FSH (AspenBio) to the maturation of ovine oocytes in terms of cumulus expansion and progression to the MII stage. Abattoir-derived sheep cumulus–oocyte complexes (COC) were obtained from 1- to 5-mm-diameter antral follicles by ovary slicing. Oocytes with a homogeneous cytoplasm surrounded by at least 3 layers of cumulus cells were selected and cultured in serum-free IVM medium (Cotterill et al. 2012 Reproduction 144, 195–207) at 38.5°C and 5% CO2. The COC obtained from 8 replicates were allocated into 4 experimental groups: (1) no hormones; (2) 1.5 μg mL–1 recombinant bovine LH (rbLH); (3) 1.5 μg mL–1 recombinant bovine FSH (rbFSH); and (4) rbLH and rbFSH. The expansion of cumulus cells was recorded in each group after 24 h of IVM and COC classified as (1) very poor or no cumulus expansion (grade 1); (2) limited cumulus expansion (grade 2); and (3) full cumulus expansion (grade 3). Nuclear maturation in the 4 treatments was evaluated by assessing progression to the MII stage via DNA staining with Hoechst 33342 and fluorescence imaging. The effect of treatment on the observed proportion of MII oocytes was evaluated using a mixed logit model including treatment and replicate as fixed and random effects, respectively. Culture in IVM medium in the absence of gonadotropins or in the presence of rbLH resulted in poor cumulus expansion (grade 1). The supplementation of IVM medium with rbFSH (with or without rbLH) yielded a high degree of cumulus expansion (grades 2–3). Likewise, addition of rbFSH enhanced progression of oocytes to the MII stage, whereas use of rbLH, although it had an effect on progression to MII, did not augment the effect of rbFSH (Table 1). These results indicate that rbFSH is necessary and sufficient to induce sheep oocyte maturation in a high proportion of oocytes. Table 1.Cumulus expansion and oocyte nuclear stage after IVM

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Interleukin-6 (IL-6) Induces Cumulus Expansion and Improves Oocyte Competence When Present During Mouse In Vitro Oocyte Maturation (IVM).

Biology of Reproduction ◽

10.1093/biolreprod/78.s1.311b ◽

2008 ◽

Vol 78 (Suppl_1) ◽

pp. 311-311 ◽

Cited By ~ 2

Author(s):

Daniel de Matos ◽

Cam Anh Tran ◽

David Kagan ◽

Selvaraj Nataraja ◽

Stephen Palmer

Keyword(s):

Oocyte Maturation ◽

Interleukin 6 ◽

Cumulus Expansion ◽

Oocyte Competence ◽

In Vitro Oocyte Maturation

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311EFFECT OF OOCYTE MATURATION MEDIA ON THE SPEED OF MEIOTIC PROGRESSION AND BLASTOCYST DEVELOPMENT OF BOVINE EMBRYOS

Reproduction Fertility and Development ◽

10.1071/rdv16n1ab311 ◽

2004 ◽

Vol 16 (2) ◽

pp. 275

Author(s):

D. Fischer ◽

J. Bordignon ◽

C. Robert ◽

D. Betts

Keyword(s):

Embryo Development ◽

Oocyte Maturation ◽

Immunofluorescence Microscopy ◽

Chromosomal Abnormalities ◽

Culture Media ◽

Blastocyst Formation ◽

Blastocyst Development ◽

Nuclear Maturation ◽

Meiotic Progression

Environment is crucial for in vitro development of gametes and embryos. The recent progression of culture media towards defined conditions brought to surface the impact of different medium supplements on oocyte and embryo development. In this work we evaluate the effect of various oocyte culture media on bovine oocyte maturation and subsequent embryo development. Bovine cumulus-oocyte complexes were recovered from slaughterhouse ovaries and matured in vitro in either TCM-199 (Gibco) or SOF (Synthetic Oviduct Fluid) media supplemented with BSA (fatty acid-free) or serum (fetal bovine serum). Oocytes from each treatment group were denuded and fixed at 18, 20, 22, 24, 26 and 28h post-maturation (p.m.). Oocyte meiotic progression was monitored in each of the groups (n=28–40 oocytes/group) by immunofluorescence microscopy of chromatin. Oocytes matured in SOF showed a slower rate of meiotic progression when compared to the other groups, with the highest percentage of oocytes reaching the MII stage by 28h p.m. (60.71% SOF-BSA, 71.43% SOF-Serum). The fastest developmental rate was observed in oocytes matured in TCM-serum (77.15% at 24h p.m.) followed by oocytes matured in TCM-BSA (74.29% at 26h p.m.). In order to evaluate the effect of nuclear maturation on chromosome segregation, chromosomal organization of MII oocytes was evaluated by immunofluorescence microscopy within each media group (n=26–31 oocytes/group) at 18, 22 and 26h p.m.. No chromosomal abnormalities were found at 18h p.m.. Both media supplemented with BSA induced lower frequencies of chromosomal abnormalities (0 to 3.23%) and (3.57 to 7.69%) for SOF and TCM, respectively, when compared to their serum-supplemented counterparts (7.14 to 11.54%) and (10 to 10.71%) for SOF and TCM, respectively at 22 and 26h p.m.. Remarkably, the maturation medium and its supplements influenced the speed of blastocyst development. For this experiment, oocytes were matured in TCM-BSA, TCM-Serum, SOF-BSA or SOF-serum, fertilized in vitro in a TALP-base media supplemented with BSA and cultured in SOF-BSA. Blastocyst development was assessed at 7, 8 and 9 days of culture. Cleavage rates were similar between the groups (84–90%), whereas development rates to blastocyst stage varied among treatment groups. Maturation in SOF-BSA induced a delay in blastocyst formation that reached its highest percentage only on day 9 of culture (30.8%); moreover, blastocyst development was carried over until Day 12. When oocytes were matured in the presence of serum, the number of blastocysts did not increase after Day 8 of culture (26.6%, TCM-serum). These results provide evidence of a severe impact of oocyte culture media on the nuclear maturation of oocytes and their subsequent embryonic development after IVF. Moreover, the difference in the rate of oocyte maturation and blastocyst formation emphasizes the necessity for reviewing and adapting current protocols to new systems such as SOF-BSA. [Research funded by NSERC and OMAF of Canada.]

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Glucose in a maturation medium with reduced NaCl improves oocyte maturation and embryonic development after somatic cell nuclear transfer and in vitro fertilization in pigs

Zygote ◽

10.1017/s0967199420000891 ◽

2021 ◽

pp. 1-8

Author(s):

Yongjin Lee ◽

Hanna Lee ◽

Joohyeong Lee ◽

Seung Tae Lee ◽

Geun-Shik Lee ◽

...

Keyword(s):

Embryonic Development ◽

Somatic Cell ◽

Oocyte Maturation ◽

Somatic Cell Nuclear Transfer ◽

Nuclear Transfer ◽

Blastocyst Formation ◽

Nuclear Maturation ◽

Maturation Medium ◽

Glucose Supplementation

Summary This study was conducted to examine whether glucose in maturation medium containing reduced NaCl could improve oocyte maturation and embryonic development in pigs. The base medium was bovine serum albumin-free porcine zygote medium (PZM)-3 containing 10% (v/v) pig follicular fluid (FPZM) or 0.1% (w/v) polyvinyl alcohol (PPZM). Using each medium, the effects of NaCl concentrations (108 and 61.6 mM) and 5.56 mM glucose supplementation (designated as PZM108N, PZM108G, PZM61N, and PZM61G, respectively) were examined using a 2 × 2 factorial arrangement. When oocytes were matured in FPZM, glucose supplementation improved nuclear maturation compared with no supplementation, regardless of the NaCl concentrations. FPZM61G showed a higher blastocyst formation compared with FPZM108N and FPZM108G after parthenogenesis (PA). Blastocyst formations of somatic cell nuclear transfer (SCNT) embryos derived from FPZM61N and FPZM61G were higher compared with those of oocytes from FPZM108N. When oocytes were matured in PPZM, glucose added to PPZM108 and PPZM61 increased nuclear maturation compared with no supplementation. However, glucose added to PPZM108 did not alter embryonic development after PA. Additionally, oocytes matured in PPZM61G showed a higher blastocyst formation compared with those from PPZM61N. In SCNT, blastocyst formation was not influenced by glucose supplementation of PPZM108, but was increased by maturation in glucose-supplemented PPZM61. In embryonic development of in vitro fertilization (IVF), oocytes matured in medium with reduced NaCl and glucose showed significantly higher blastocyst formation compared with those matured in PPZM108G. Our results demonstrated that glucose in maturation medium containing 61.6 mM NaCl increased oocyte maturation and embryonic development after PA, SCNT, and IVF.

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The effect of FF-MAS on porcine cumulus–oocyte complex maturation, fertilization and pronucleus formation in vitro

Zygote ◽

10.1017/s0967199406003765 ◽

2006 ◽

Vol 14 (3) ◽

pp. 189-199 ◽

Cited By ~ 16

Author(s):

Inger Faerge ◽

Frantisek Strejcek ◽

Jozef Laurincik ◽

Detlef Rath ◽

Heiner Niemann ◽

...

Keyword(s):

Oocyte Maturation ◽

Follicular Fluid ◽

Developmental Potential ◽

Nuclear Maturation ◽

Cumulus Oocyte Complex ◽

Constant Ph ◽

Porcine Oocyte ◽

Fine Glass ◽

Epidermal Growth

SummaryFollicular fluid meiosis-activating sterol (FF-MAS) has been isolated from the follicular fluid (FF) of several species including man. FF-MAS increases the quality of in vitro oocyte maturation, and thus the developmental potential of oocytes exposed to FF-MAS during in vitro maturation is improved. The aim of the present study was to investigate the effects of FF-MAS on porcine oocyte maturation and pronucleus formation in vitro. Porcine cumulus–oocyte complexes (COCs) were isolated from abattoir ovaries and in vitro matured for 48 h in NCSU 37 medium supplemented with 1 mg/l cysteine, 10 ng/ml epidermal growth factor and 50 μM 2-mercaptoethanol with or without 10% porcine follicular fluid (pFF). For the first 22 h, 1 mM db-cAMP and 10 I.E PMSG/hCG was added. The medium was supplemented with 1 μM, 3 μM, 10 μM, 30 μM or 100 μM FF-MAS dissolved in ethanol. After maturation the COCs were denuded mechanically using a fine glass pipette under constant pH and in vitro fertilized with fresh semen (5 × 105 spermatozoa/ml). The presumptive zygotes were evaluated 18 h after fertilization. The addition of pFF increased the monospermic as well as the polyspermic penetration of oocytes. In the absence of pFF, the addition of FF-MAS decreased the polyspermic penetration rate, whereas FF-MAS in combination with pFF decreased monospermic and increased polyspermic penetration. The degeneration rate of ova decreased in the presence of FF-MAS irrespective of the presence or absence of pFF. In the absence of pFF, FF-MAS at 3–10 μM increased the number of zygotes with advanced maternal pronuclear stages. In supraphysiological doses, i.e. 30–100 μM, FF-MAS dose-dependently and reversibly inhibited nuclear maturation in the absence of pFF.

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