scholarly journals Effect of varying glucose and glucosamine concentration in vitro on mouse oocyte maturation and developmental competence

2013 ◽  
Vol 25 (8) ◽  
pp. 1095 ◽  
Author(s):  
L. A. Frank ◽  
M. L. Sutton-McDowall ◽  
D. L. Russell ◽  
X. Wang ◽  
D. K. Feil ◽  
...  
Keyword(s):  
Oocyte Maturation ◽  
In Vitro Maturation ◽  
Blastocyst Stage ◽  
Developmental Competence ◽  
Blastocyst Development ◽  
Oocyte Competence ◽  
Hexosamine Pathway ◽  
Hexosamine Biosynthesis ◽  
Necessary And Sufficient

The effects of hyper- and hypo-glycaemic conditions during the in vitro maturation of mouse cumulus–oocyte complexes on developmental competence were examined, with an emphasis on the role of the hexosamine biosynthesis pathway. A low (1 mM) glucose concentration achieved optimal oocyte competence (3-fold higher blastocyst development rate compared with high (30 mM) glucose, P < 0.05). In addition, glucose supplementation during only the first hour after release from the follicle was necessary and sufficient to support oocyte maturation and embryo development to the blastocyst stage. Glucosamine (a known hyperglycaemic mimetic and specific activator of the hexosamine pathway) was able to substitute for glucose during this first hour, indicating that flux through the hexosamine pathway is essential for oocyte competence. In the absence of glucose throughout the maturation period, glucosamine was not able to increase developmental competence, and at higher concentrations (2.5 and 5 mM) had a detrimental effect on MII and blastocyst development rates, compared with controls (P < 0.05). These experiments underscore the importance of glucose metabolic pathways during in vitro maturation and support the concept that excess flux through the hexosamine pathway has detrimental consequences.

scholarly journals Oocyte Competence Biomarkers Associated With Oocyte Maturation: A Review

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.

246 IN VITRO PRODUCTION OF SPRINGBOK (ANTIDORCAS MARSUPIALIS) EMBRYOS

2007 ◽  
Vol 19 (1) ◽  
pp. 239 ◽  
Author(s):  
R. Krisher ◽  
A. Auer ◽  
K. Clark ◽  
K. Emsweller ◽  
S. Rogers ◽  
...  
Keyword(s):  
South Africa ◽  
Oocyte Maturation ◽  
Assisted Reproductive Technologies ◽  
Reproductive Technologies ◽  
Blastocyst Stage ◽  
Developmental Competence ◽  
Genetic Management ◽  
Blastocyst Development ◽  
Antidorcas Marsupialis

The objective of this experiment was to develop in vitro embryo production (IVP) technologies in springbok (Antidorcas marsupialis), a southern African antelope. Springbok, a fairly common species on game farms in parts of South Africa, may be used as a model species for gamete rescue and IVP techniques to be applied to the conservation of other threatened antelope species. Springbok belong to the family bovidae, subfamily antilopinae, tribe antilopini, which comprises about twenty species in genera Gazella, Antilope, Procapra, Antidorcas, Litocranius, and Ammodorcas. In this tribe alone, there are 4 species or subspecies that are critically endangered, 3 that are endangered, and 10 that are considered vulnerable, demonstrating the need for antelope conservation efforts. In addition, our studies contributed to the South African biological resource bank, so that banked springbok semen and embryos might be used in the future for managed genetic contribution to isolated captive or wild populations via assisted reproductive technologies. Oocytes were recovered (3 replicates) from ovaries obtained at supervised culls for management purposes in South Africa, and cultured in defined Gmat or undefined TCM-199 with FCS maturation medium for 28-30 h (Brad et al. 2004 Reprod. Fertil. Dev. 16, 223). Oocytes were fertilized with frozen-thawed springbok epididymal spermatozoa in modified SOF fertilization medium with caffeine (Herrick et al. 2004 Biol. Reprod. 71, 948–958). Eighteen hours after insemination, a randomly selected subset of the zygotes were fixed to determine fertilization success. The remaining zygotes were cultured in G1/G2 media. On Day 7 of culture, embryos were analyzed for development to the morula or blastocyst stage. A total of 259 selected oocytes were collected from 50 females (5.2 selected oocytes/female on average). There was no difference in the percentage of oocytes normally fertilized (2 pronuclei, PN) between oocytes matured in Gmat (n= 43; 12%) and those matured in TCM-199 (n= 42; 10%). There were significantly (P &lt; 0.05) more oocytes penetrated (e2 PN) when matured in TCM (50%) compared to Gmat (23%). There were no differences in embryonic cleavage or morula/blastocyst development (of total oocytes inseminated) between treatments (Gmat,n= 89, 54%, 9.0%; TCM-199, n= 85, 68%, 9.4%, respectively). In both treatments, the average blastocyst grade was 2.125 using the standard bovine grading system (Curtis, Cattle Embryo Transfer Procedure, 1991). In conclusion, in vitro oocyte maturation, fertilization, and embryo culture to the blastocyst stage is possible in springbok. Importantly, blastocysts can be produced in vitro under semi-defined conditions, demonstrating that oocyte maturation without serum does support developmental competence. This is important for the potential international movement of IVP embryos to be used for genetic management in the conservation of antelope species.

scholarly journals 324SPHINGOSINE-1-PHOSPHATE PROTECTS CULTURED BOVINE OOCYTES FROM PHYSIOLOGICALLY RELEVANT THERMAL STRESS

2004 ◽  
Vol 16 (2) ◽  
pp. 282 ◽  
Author(s):  
Z. Roth ◽  
P.J. Hansen
Keyword(s):  
Thermal Stress ◽  
Heat Shock ◽  
Blastocyst Stage ◽  
Caspase Activity ◽  
Blastocyst Development ◽  
Cleavage Rate ◽  
Developmental Potential ◽  
Oocyte Competence ◽  
Cell Death Pathway

Sphingosine-1-phosphate (S1P) is a sphingolipid metabolite that can block the sphingomyelin cell-death pathway by suppressing ceramide-induced apoptosis. The present study was performed to test whether S1P protects oocytes from heat shock during in vitro maturation. Cumulus-oocyte complexes obtained by slicing follicles were placed in maturation medium with or without 50nM S1P and cultured at 38.5°C (CON) or 41°C (41C) for the first 12h of maturation. Incubation during the last 10h of maturation (22-h total maturation time), fertilization, and embryonic development were performed at 38.5°C and 5% (v/v) CO2. Blastocyst development was recorded at 8 days post-insemination (dpi) and activity of group II caspases in 8-day blastocysts was determined using a fluoroprobe, PhiPhiLux-G1D2 (OncoImmunin, Gaithersburg, MD, USA). Data were analysed by least-squares ANOVA with the GLM procedure of SAS. Percentage data were subjected to arcsin transformation before analysis. Exposure of oocytes to thermal stress during the first 12h of maturation reduced cleavage rate (P&lt;0.01) and the number of oocytes developing to the blastocyst stage (P&lt;0.04). There was a temperature x S1P interaction for cleavage rate (P&lt;0.03) because S1P blocked effects of thermal stress on cleavage rate. Without S1P, the percentage of oocytes that cleaved by 3 dpi were 83.6±2.7% and 65.8±2.7% for CON and 41C, respectively. In the presence of S1P, percent cleavage was 86.7±2.7% and 83.9±2.7% for CON and 41C, respectively. There was a trend (P=0.06) for a temperature x S1P interaction for percent oocytes developing to blastocyst stage because S1P blocked effects of heat shock on development. Without S1P, the percentages of oocytes that developed to the blastocyst stage were 28.7±3.0% and 15.2±3.0% for CON and 41C, respectively. In the presence of S1P, percent blastocysts were 24.3±3.4% and 23.9±3.0% for CON and 41C, respectively. When development was expressed as percentage of cleaved embryos, however, there were no effects of temperature, S1P, or temperature x S1P on percent development to the blastocyst stage. Blastocyst caspase activity was not affected by temperature or S1P. In summary, exposure to physiologically relevant thermal stress during the first 12h of maturation has a deleterious effect on oocyte competence and this effect can be reduced by S1P. The fact that heat shock reduced the percentage of oocytes but not the percentage of cleaved embryos that became blastocysts suggests that oocytes that survive effects of heat shock and cleave have normal potential to develop to the blastocyst stage. Moreover, since heat shock did not affect caspase activity, it is likely that blastocysts from heat-shocked oocytes have normal developmental potential, at least as determined by caspase activity. Support: BARD FI-330-2002 and USDA Grants 2002-35203-12664 and 2001-52101-11318.

327 OOCYTE-SECRETED FACTORS DIRECTLY AFFECT OOCYTE DEVELOPMENTAL COMPETENCE DURING IN VITRO MATURATION OF THE BOVINE CUMULUS - OOCYTE COMPLEX

2006 ◽  
Vol 18 (2) ◽  
pp. 271 ◽  
Author(s):  
T. S. Hussein ◽  
R. B. Gilchrist ◽  
J. G. Thompson
Keyword(s):  
In Vitro Maturation ◽  
Cumulus Cell ◽  
Blastocyst Stage ◽  
Developmental Competence ◽  
Bovine Oocyte ◽  
Paracrine Factors ◽  
Cell Functions ◽  
Oocyte Developmental Competence ◽  
Secreted Factors

Paracrine factors secreted by the oocyte (oocyte-secreted factors, OSFs) regulate a broad range of cumulus cell functions including proliferation, differentiation, and apoptosis. The capacity of oocytes to regulate their own microenvironment by OSFs may in turn contribute to oocyte developmental competence. The aim of this study was to determine if OSFs have a direct influence on bovine oocyte developmental competence during in vitro maturation (IVM). Cumulus-oocyte complexes (COCs) were obtained by aspiration of >3-mm follicles from abattoir-derived ovaries. IVM was conducted in Bovine VitroMat (Cook Australia, Eight Mile Plains, Brisbane, Australia) supplemented with 0.1 IU/mL rhFSH for 24 h under 6% CO2 in air at 38.5�C. In the first experiment, COCs were co-cultured with denuded oocytes (DOs, 5/COC in 10 �L) beginning at either 0 or 9-h of IVM. To generate the 9-h DO group, COCs were first cultured intact for 9-h and then denuded. In the second experiment, specific OSFs, recombinant bone morphogenetic protein-15 (BMP-15) and growth differentiation factor 9 (GDF-9), were prepared as partially purified supernatants of transfected 293H cells, and used as 10% v/v supplements in Bovine VitroMat. Treatments were: (1) control (no supplement), (2) BMP-15, (3) GDF-9, (4) BMP-15 and GDF-9, and (5) untransfected 293H control. Following maturation, in vitro production of embryos was performed using the Bovine Vitro system (Cook Australia) and blastocysts were examined on Day 8 for development. Developmental data were arcsine-transformed and analyzed by ANOVA, followed by Tukey's test. Cell numbers were analyzed by ANOVA. Co-culturing intact COCs with DOs from 0 or 9 h did not affect cleavage rate, but increased (P < 0.001) the proportion of cleaved embryos that reached the blastocyst stage post-insemination (50.6 � 1.9 and 61.3 � 1.9%, respectively), compared to COCs cultured alone (40.7 � 1.4%). Therefore, paracrine factors secreted by DOs increased the developmental competence of oocytes matured as COCs. OSFs also improved embryo quality, as co-culture of COCs with DOs (0 or 9 h) significantly increased total cell (156.1 � 1.3 and 159.1 � 1.3, respectively) and trophectoderm (105.7 � 1.3 and 109.8 � 0.4, respectively) numbers, compared to control COCs (total = 148 � 1.2, trophectoderm = 98.2 � 0.8, P < 0.001). BMP-15 alone or with GDF-9 also significantly (P < 0.001) increased the proportion of oocytes that reached the blastocyst stage post insemination (57.5 � 2.4% and 55.1 � 4.5%, respectively), compared to control (41.0 � 0.9%) and 293H-treated (27.1 � 3.1%) COCs. GDF-9 also increased blastocyst yield (49.5 � 3.9%) but not significantly. These results are the first to demonstrate that OSFs, and particularly BMP-15 and GDF-9, directly affect bovine oocyte developmental competence. These results have far-reaching implications for improving the efficiency of IVM in domestic species and human infertility treatment, and support the role of OSF production by oocytes as a diagnostic marker for developmental competence.

249 FOLLICLE-STIMULATING HORMONE AND DIBUTYRYL cAMP TREATMENTS DURING IN VITRO MATURATION IMPROVE THE DEVELOPMENTAL COMPETENCE OF MOUSE OOCYTES

2008 ◽  
Vol 20 (1) ◽  
pp. 204
Author(s):  
R. Oishi ◽  
Y. Isaji ◽  
H. Imai ◽  
M. Yamada
Keyword(s):  
In Vitro Maturation ◽  
Basal Medium ◽  
Cumulus Cells ◽  
Blastocyst Stage ◽  
Developmental Competence ◽  
Control Medium ◽  
Dibutyryl Camp ◽  
Mouse Oocytes ◽  
Junctional Communication

The high level of cyclic adenosine monophosphate (cAMP), which is provided to the oocytes from cumulus cells via gap junctional complexes in cumulus-enclosed oocytes (CEOs), is known to contribute to meiotic arrest at the germinal vesicle (GV) stage of CEOs. However, whether intraoocyte cAMP during the period of in vitro maturation (IVM) affects postfertilization developmental competence of mouse oocytes still remains unclear. The aim of this study was to examine the effects of FSH or dibutyryl cAMP (dbcAMP) treatment during IVM on in vitro development of mouse oocytes after in vitro fertilization (IVF). Whether a junctional association between cumulus cells and the oocyte would be essential for a cytoplasmic maturation-promoting effect was also examined. CEOs were isolated from and eCG-primed 3-week-old ICR mouse by rupturing preovulatory follicles with needles in M16 medium with 5% FCS and essential and nonessential amino acids (basal medium). IVM media used were basal medium without (control) or with 100 µm dbcAMP or 1 IU mL–1 FSH. Carbenoxolone (100 µm, CBX), an inhibitor of gap junction, was used to inhibit a junctional association between cumulus cells and the oocyte. Denuded oocytes (DOs) were prepared by repeatedly pipetting in basal medium with 0.2% hyaluronidase. CEOs and DOs were cultured in IVM media at 37�C under 5% CO2 in air for 16.5 h, and then transferred to TYH medium (a modified Krebs-Ringer bicarbonate medium) containing 0.4% BSA, followed by insemination with capacitated sperm. After 6 h of IVF, inseminated oocytes were cultured in KSOM medium with 0.3% BSA. Development to the 2-cell and blastocyst stages was estimated at 24 h and 120 h after IVF, respectively. All experiments were done in 3 replicates, and the statistical analysis was carried out by ANOVA and Fisher's protected least-squares difference (PLSD) test. When CEOs were matured in IVM media, the rates of postfertilization development to the 2-cell and blastocyst stages of oocytes matured in the control medium were very low(29% and 13%, respectively), whereas those of oocytes matured with FSH or dbcAMP significantly increased (FSH: 61% and 52%, dbcAMP: 63 and 57%, respectively, v. control; P < 0.05). Next, when CEOs were matured in basal medium with 1 IU mL–1 FSH and 100 µm CBX, the developmental rate to the 2-cell stage (56%) was similar to that in medium with FSH alone (61%) but the rate to the blastocyst stage (40%) was little lower compared with that in medium with FSH alone (52%), although not significantly different (P > 0.05). Furthermore, when DOs were matured in IVM media, the developmental rates to the blastocyst stage after IVF of the oocytes matured with FSH or dbcAMP significantly increased (FSH: 25%, dbcAMP: 15%; P < 0.05) compared with those in control medium (7%). Taken together, it is suggested that increasing the concentration of intraoocyte cAMP during the IVM period is important to improve the developmental competence after IVF of mouse oocytes, and that the competence is acquired in part in a cumulus-oocyte junctional communication-independent manner.

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

2014 ◽  
Vol 26 (1) ◽  
pp. 200 ◽  
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

233. Oxygen concentration during in vitro maturation of murine oocytes affects blastocyst cell lineage

2005 ◽  
Vol 17 (9) ◽  
pp. 91
Author(s):  
K. M. Banwell ◽  
M. Lane ◽  
D. L. Russell ◽  
K. L. Kind ◽  
J. G. Thompson
Keyword(s):  
Embryo Development ◽  
In Vitro Maturation ◽  
Cell Lineage ◽  
Developmental Competence ◽  
Embryo Viability ◽  
Blastocyst Development ◽  
Treatment Groups ◽  
Significant Difference ◽  
O2 Concentration

Follicular antral oxygen tension is thought to influence subsequent oocyte developmental competence. Despite this, in vitro maturation (IVM) is routinely performed in either 5 or 20% O2 and while low O2 has been shown to be beneficial to embryo development in many species, the effect of altering O2 concentration during IVM has not been adequately investigated. Here we investigated the effects of a range of O2 concentrations during IVM on meiotic maturation and subsequent embryo development after IVF. Ovaries from eCG-stimulated CBA F1 female mice (21 days) were collected and intact cumulus oocyte complexes (COCs) cultured for 17–18 h under 2, 5, 10 or 20% O2 (6% CO2 and balance of N2). Matured COCs were denuded of cumulus cells, fixed and stained (1% aceto-orcein) for visualisation of maturation status. No significant difference in maturation rates between treatment groups was observed. Following IVF (performed under 5% O2, 6% CO2 and balance of N2), no difference in fertilisation rates between treatment groups was observed in a randomly selected cohort 7 h post-fertilisation. There was also no significant difference in cleavage rates after 24 h or ability to reach blastocyst stage after 96 h, with a tendency (P = 0.079) for more blastocysts in 2% O2. However there was a significant increase in the number of trophectoderm cells present in the resulting blastocysts (P < 0.05) in the 2% O2 group (35 ± 2.1) compared to 20% O2 (25 ± 2.8). Our data suggests that O2 concentration during IVM does not influence nuclear maturation or subsequent fertilisation, cleavage and blastocyst development rates. However, maturation in 2% O2 significantly alters subsequent cell lineage within blastocysts to favour trophectoderm development. Such skewed trophectoderm cell number may influence embryo viability. Funded by NHMRC and NIH.

Paradoxical effects of kisspeptin: it enhances oocyte in vitro maturation but has an adverse impact on hatched blastocysts during in vitro culture

2012 ◽  
Vol 24 (5) ◽  
pp. 656 ◽  
Author(s):  
Islam M. Saadeldin ◽  
Ok Jae Koo ◽  
Jung Taek Kang ◽  
Dae Kee Kwon ◽  
Sol Ji Park ◽  
...  
Keyword(s):  
Oocyte Maturation ◽  
In Vitro Maturation ◽  
Formation Rate ◽  
Early Period ◽  
Threshold Effect ◽  
Developmental Competence ◽  
Control Group ◽  
Maturation Medium ◽  
Paradoxical Effects

Kisspeptin (Kp) is best known as a multifunctional peptide with roles in reproduction, the cardiovascular system and cancer. In the present study the expression of kisspeptin hierarchy elements (KISS1, GNRH1 and LHB) and their receptors (KISS1R, GNRHR and LHCGR, respectively) in porcine ovary and in cumulus–oocyte complexes (COCs) were investigated, as were its effects on the in vitro maturation (IVM) of oocytes and their subsequent ability to sustain preimplantation embryo competence after parthenogenetic electrical activation. Kp system elements were expressed and affected IVM of oocytes when maturation medium was supplemented with 10–6 M Kp. Oocyte maturation, maternal gene expression (MOS, GDF9 and BMP15), blastocyst formation rate, blastocyst hatching and blastocyst total cell count were all significantly increased when oocytes were matured in medium containing Kp compared with the control group (without Kp). A Kp antagonist (p234) at 4 × 10–6 M interfered with this hierarchy but did not influence the threshold effect of gonadotrophins on oocyte maturation. FSH was critical and permissive to Kp action on COCs by increasing the relative expression of KISS1R. In contrast, Kp significantly increased apoptosis, the expression of pro-apoptotic gene, BAK1, and suppressed trophoblast outgrowths from hatched blastocysts cultured on feeder cells. The present study provides the first functional evidence of the Kp hierarchy in porcine COCs and its role in enhancing oocyte maturation and subsequent developmental competence in an autocrine–paracrine manner. However, Kp supplementation may have a harmful impact on cultured hatched blastocysts reflecting systemic or local regulation during the critical early period of embryonic development.

Relationship between follicle size and oocyte developmental competence in prepubertal and adult pigs

2007 ◽  
Vol 19 (7) ◽  
pp. 797 ◽  
Author(s):  
Melanie A. Bagg ◽  
Mark B. Nottle ◽  
David T. Armstrong ◽  
Christopher G. Grupen
Keyword(s):  
In Vitro Maturation ◽  
Fold Increase ◽  
Cell Number ◽  
Developmental Competence ◽  
Blastocyst Development ◽  
Parthenogenetic Activation ◽  
Follicle Size ◽  
Low Efficiency ◽  
The Relationship

The present study compared the distribution and steroid composition of 3-, 4- and 5–8-mm follicles on the surface of prepubertal and adult ovaries, and determined the relationship between follicle size and developmental competence of oocytes following parthenogenetic activation. The effect of 1 mm dibutyryl cAMP (dbcAMP) for the first 22 h of in vitro maturation (IVM) on the embryo development of prepubertal oocytes from the three follicle size cohorts was also determined. Compared with adult, prepubertal ovaries contained a higher proportion of 3-mm follicles (46 v. 72%, respectively), but a lower proportion of 4-mm (33 v. 22%, respectively) and 5–8-mm follicles (21 v. 6%, respectively). Adult follicular fluid (FF) contained 11-fold higher levels of progesterone (P4) than prepubertal FF, with similar levels observed between all adult follicle sizes. In prepubertal FF, the P4 concentration increased with follicle size from 3 to 4 to 5–8 mm. Rates of blastocyst development following parthenogenetic activation of adult oocytes from all three follicles sizes were similar (approximately 55%), whereas rates from prepubertal oocytes increased with increasing follicle size from 3 (17%) to 4 (36%) to 5–8 mm (55%). Treatment with dbcAMP for the first 22 h of IVM led to a 1.5-fold increase in the rate of blastocyst development for prepubertal oocytes from 3-mm follicles, but had no effect on prepubertal oocytes from the 4 and 5–8 mm classes. Mean blastocyst cell number increased with follicle size in prepubertal ovaries and was similar for all follicle sizes in adult ovaries. The present study demonstrates that the low efficiency of in vitro embryo production observed using prepubertal compared with adult pig oocytes is due to a greater proportion of 3-mm follicles on prepubertal ovaries, which contain oocytes of inferior developmental competence.

scholarly journals Effect of epidermal growth factor-like peptides on pig cumulus cell expansion, oocyte maturation, and acquisition of developmental competence in vitro: comparison with gonadotropins

Reproduction ◽  
2011 ◽  
Vol 141 (4) ◽  
pp. 425-435 ◽  
Author(s):  
Radek Procházka ◽  
Michal Petlach ◽  
Eva Nagyová ◽  
Lucie Němcová
Keyword(s):  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Oocyte Maturation ◽  
Cumulus Cell ◽  
Cumulus Cells ◽  
Blastocyst Stage ◽  
Human Chorionic Gonadotrophin ◽  
Developmental Competence ◽  
Epidermal Growth

The aim of this work was to assess the FSH-stimulated expression of epidermal growth factor (EGF)-like peptides in cultured cumulus–oocyte complexes (COCs) and to find out the effect of the peptides on cumulus expansion, oocyte maturation, and acquisition of developmental competencein vitro. FSH promptly stimulated expression of amphiregulin (AREG) and epiregulin (EREG), but not betacellulin (BTC) in the cultured COCs. Expression ofAREGandEREGreached maximum at 2 or 4 h after FSH addition respectively. FSH also significantly stimulated expression of expansion-related genes (PTGS2,TNFAIP6, andHAS2) in the COCs at 4 and 8 h of culture, with a significant decrease at 20 h of culture. Both AREG and EREG also increased expression of the expansion-related genes; however, the relative abundance of mRNA for each gene was much lower than in the FSH-stimulated COCs. In contrast to FSH, AREG and EREG neither stimulated expression ofCYP11A1in the COCs nor an increase in progesterone production by cumulus cells. AREG and EREG stimulated maturation of oocytes and expansion of cumulus cells, although the percentage of oocytes that had reached metaphase II was significantly lower when compared to FSH-induced maturation. Nevertheless, significantly more oocytes stimulated with AREG and/or EREG developed to blastocyst stage after parthenogenetic activation when compared to oocytes stimulated with FSH alone or combinations of FSH/LH or pregnant mares serum gonadotrophin/human chorionic gonadotrophin. We conclude that EGF-like peptides do not mimic all effects of FSH on the cultured COCs; nevertheless, they yield oocytes with superior developmental competence.

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