Effect of Co-Culture with Mammalian Spermatozoa on Maturation in vitro of Porcine Cumulus-Free Germinal Vesicle Oocytes

The involvement of the ovarian follicle wall in insulin induction of Rana pipiens oocyte maturation in vitro was examined. Complete removal of the follicle wall significantly decreased, but did not obliterate, oocyte maturation (i.e., germinal vesicle breakdown, GVBD) induced by insulin. Dose-response studies of GVBD induction revealed that oocytes within intact follicles were at least 100 times more sensitive to insulin than denuded oocytes. Addition of cyanoketone, a steroid biosynthesis inhibitor, to intact follicles also suppressed insulin-induced GVBD. Inhibitory effects of either follicle wall removal or cyanoketone were not observed when denuded oocytes were treated with progesterone. Addition of either progesterone or pregnenolone to insulin-treated denuded oocytes augmented the oocyte GVBD response compared to either steroid alone and essentially replaced the effect of the follicle wall. In summary, steroidogenesis in the follicle wall appears to be a major factor contributing to the ability of insulin to induce GVBD. However, whether insulin stimulates follicle wall steroidogenesis or simply augments the biological activity of endogenous basal steroid levels is unresolved. The in vitro results show that oocyte maturation can be modulated by the combined actions of several hormones. Such steroid-insulin interactions may also be relevant to understanding the control of oocyte maturation in amphibians and other vertebrates, including mammals, under physiological conditions in vivo.

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329 EXPRESSION AND REGULATION OF GENOMIC AND NON-GENOMIC PROGESTERONE RECEPTORS IN BOVINE CUMULUS - OOCYTE COMPLEXES DURING MATURATION IN VITRO

Reproduction Fertility and Development ◽

10.1071/rdv22n1ab329 ◽

2010 ◽

Vol 22 (1) ◽

pp. 320

Author(s):

I. M. Aparicio ◽

C. Hensey ◽

P. Lonergan ◽

T. Fair

Keyword(s):

Cumulus Cell ◽

Progesterone Receptors ◽

Germinal Vesicle ◽

Cumulus Cells ◽

Maturation In Vitro ◽

Epidermal Growth ◽

Specific Receptors ◽

Reproductive Events ◽

Cell Expression

The steroid hormone, progesterone (P4) plays an essential role in the regulation of female reproductive events. It acts by binding to specific receptors classified as genomic (nPR-A, nPR-B) and non-genomic (mPRα, mPRβ, PGRMC1, PGRMC2) progesterone receptors (PRs). The aim of the present work was to identify and characterize the PRs that are expressed in bovine COCs during IVM. Immature COCs collected from the ovaries of slaughtered animals and either allocated to analysis at the immature, germinal vesicle stage (GV) or processed for IVM and collected at the metaphase II stage (MII) of meiosis. Groups of up to 50 COCs were placed in 500 mL of maturation medium (TCM-199) supplemented with 10% (v/v) FCS and 10 ng mL-1 epidermal growth factor without or with FSH (100 ng mL-1), LH (100 ng mL-1), or P4 (10, 100, 500 ng m-1), in 4-well dishes and cultured at 39°C for 24 h in a humidified atmosphere containing 5% CO2. GV and MII COCs were stripped of their cumulus cells and 100 oocytes and 10 μg of protein from cumulus cells were resolved by SDS-PAGE using specific antibodies against the different PRs. In addition, the pattern of PR expression was characterized in wholemount preparations of GV and MII COCs by immunocytochemistry using the same antibodies. nPR-A, mPRα, and mPRβ were expressed in both bovine oocytes and their surrounding cumulus cells, while expression of nPR-B, PGRMC1, and PGRMC2 was detected solely in the cumulus cells. Cumulus cell expression of nPR-A and nPR-B, mPRα, and mPRβ increased following IVM, while PGRMC1 and PGRMC2 expression decreased. In contrast to the expression profile of the cumulus cells, nPR-A, mPRα, and mPRβ expression was downregulated following IVM in the corresponding oocytes. Supplementation of the IVM media with FSH or LH resulted in an increase in the expression of nPR-A and nPR-B in cumulus cells and a decrease of nPR-A in oocytes. In contrast, P4 supplementation (500 ng mL-1) during IVM resulted in increased cumulus cell nPR-B expression and decreased nPR-A, mPRα, and mPRβ expression in oocytes. Oocyte mPRβ expression was also downregulated by LH and FSH. PGRMC1 and PGRMC2 were upregulated by 500 and 10 ng mL-1 of P4 respectively. In conclusion, the dynamic changes observed in the protein expression of genomic and non-genomic P4 receptors in bovine COCs after IVM and after treatment with LH, FSH, and P4 suggest that some or all of these receptors may be involved in oocyte maturation in cattle. Supported by Science Foundation Ireland (07/SRC/B1156). IMAparicio was supported by a postdoctoral contract (POS07011) from Consejeria de Economia, Comercio e Innovacion, Junta de Extremadura, Spain.

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Progesterone-induced in vitro maturation in oocytes of Notophthalmus viridescens (Amphibia Urodela) and some observations on cytological aspects of maturation

Development ◽

10.1242/dev.34.2.451 ◽

1975 ◽

Vol 34 (2) ◽

pp. 451-466

Author(s):

Giuseppina Barsacchi Pilone ◽

A. A. Humphries

Keyword(s):

In Vitro Maturation ◽

Germinal Vesicle ◽

Nuclear Material ◽

Notophthalmus Viridescens ◽

Maturation In Vitro ◽

Apparent Loss ◽

In Vivo Treatment

Maturation in vitro of oocytes of the newt, Notophthalmus viridescens, is inducible with progesterone after in vivo treatment of females with gonadotropin; few oocytes mature in vitro in the absence of such gonadotropin treatment. Chromosomes of most large oocytes of animals not receiving gonadotropin are still in the lampbrush condition; chromosomes from gonadotropin-treated animals are shorter and the lateral loops are less profuse and somewhat retracted. The chromosome condition, then, can be correlated with susceptibility to progesterone induction of maturation in vitro. As maturation progresses, the germinal vesicle moves toward the surface and decreases in size, with an apparent loss of nuclear material from the centripetal end. Although lateral loops of most chromosomes disappear during the changes in the germinal vesicle, profuse loops develop during this period at the sphere loci, which were previously devoid of loops.

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Glycine ameliorates mitochondrial dysfunction caused by ABT-199 in porcine oocytes

Journal of Animal Science ◽

10.1093/jas/skab072 ◽

2021 ◽

Author(s):

Sicong Yu ◽

Lepeng Gao ◽

Yang Song ◽

Xin Ma ◽

Shuang Liang ◽

...

Keyword(s):

Oxidative Stress ◽

Mitochondrial Dysfunction ◽

Oocyte Maturation ◽

Mitochondrial Function ◽

Protective Action ◽

Damage Model ◽

Developmental Competence ◽

Free Calcium ◽

Maturation In Vitro

Abstract Mitochondria play an important role in controlling oocyte developmental competence. Our previous studies showed that glycine can regulate mitochondrial function and improve oocyte maturation in vitro. However, the mechanisms by which glycine affects mitochondrial function during oocyte maturation in vitro have not been fully investigated. In this study, we induced a mitochondrial damage model in oocytes with the Bcl-2-specific antagonist ABT-199. We investigated whether glycine could reverse the mitochondrial dysfunction induced by ABT-199 exposure and whether it is related to calcium regulation. Our results showed that ABT-199 inhibited cumulus expansion, decreased the oocyte maturation rate and the intracellular glutathione (GSH) level, caused mitochondrial dysfunction, induced oxidative stress, which was confirmed by decreased mitochondrial membrane potential (Δ⍦m) and the expression of mitochondrial function-related genes (PGC-1α), and increased reactive oxygen species (ROS) levels and the expression of apoptosis-associated genes (Bax, caspase-3, CytC). More importantly, ABT-199-treated oocytes showed an increase in the intracellular free calcium concentration ([Ca 2+]i) and had impaired cortical type 1 inositol 1,4,5-trisphosphate receptors (IP3R1) distribution. Nevertheless, treatment with glycine significantly ameliorated mitochondrial dysfunction, oxidative stress and apoptosis, glycine also regulated [Ca 2+]i levels and IP3R1 cellular distribution, which further protects oocyte maturation in ABT-199-induced porcine oocytes. Taken together, our results indicate that glycine has a protective action against ABT-199-induced mitochondrial dysfunction in porcine oocytes.

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Chronological Changes of Bovine Follicular Oocyte Maturation in Vitro

Acta Veterinaria Scandinavica ◽

10.1186/bf03548130 ◽

1986 ◽

Vol 27 (4) ◽

pp. 505-519 ◽

Cited By ~ 2

Author(s):

K. P. Xu ◽

T. Greve ◽

S. Smith ◽

P. Hyttel

Keyword(s):

Oocyte Maturation ◽

Maturation In Vitro

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Melatonin Promotes In Vitro Maturation of Vitrified-Warmed Mouse Germinal Vesicle Oocytes, Potentially by Reducing Oxidative Stress through the Nrf2 Pathway

Animals ◽

10.3390/ani11082324 ◽

2021 ◽

Vol 11 (8) ◽

pp. 2324

Author(s):

Shichao Guo ◽

Jinyu Yang ◽

Jianpeng Qin ◽

Izhar Hyder Qazi ◽

Bo Pan ◽

...

Keyword(s):

Oxidative Stress ◽

Signaling Pathway ◽

In Vitro Maturation ◽

Germinal Vesicle ◽

Melatonin Receptors ◽

Development Rates ◽

Nrf2 Signaling Pathway ◽

Mouse Gv Oocytes ◽

Intracellular Oxidative Stress

Previously it was reported that melatonin could mitigate oxidative stress caused by oocyte cryopreservation; however, the underlying molecular mechanisms which cause this remain unclear. The objective was to explore whether melatonin could reduce oxidative stress during in vitro maturation of vitrified-warmed mouse germinal vesicle (GV) oocytes through the Nrf2 signaling pathway or its receptors. During in vitro maturation of vitrified-warmed mouse GV oocytes, there were decreases (p < 0.05) in the development rates of metaphase I (MI) oocytes and metaphase II (MII) and spindle morphology grades; increases (p < 0.05) in the reactive oxygen species (ROS) levels; and decreases (p < 0.05) in expressions of Nrf2 signaling pathway-related genes (Nrf2, SOD1) and proteins (Nrf2, HO-1). However, adding 10−7 mol/L melatonin to both the warming solution and maturation solutions improved (p < 0.05) these indicators. When the Nrf2 protein was specifically inhibited by Brusatol, melatonin did not increase development rates, spindle morphology grades, genes, or protein expressions, nor did it reduce vitrification-induced intracellular oxidative stress in GV oocytes during in vitro maturation. In addition, when melatonin receptors were inhibited by luzindole, the ability of melatonin to scavenge intracellular ROS was decreased, and the expressions of genes (Nrf2, SOD1) and proteins (Nrf2, HO-1) were not restored to control levels. Therefore, we concluded that 10−7 mol/L melatonin acted on the Nrf2 signaling pathway through its receptors to regulate the expression of genes (Nrf2, SOD1) and proteins (Nrf2, HO-1), and mitigate intracellular oxidative stress, thereby enhancing in vitro development of vitrified-warmed mouse GV oocytes.

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