Effect of C-type natriuretic peptide on maturation and developmental competence of immature mouse oocytes in vitro

2017 ◽  
Vol 29 (2) ◽  
pp. 319 ◽  
Author(s):  
Qiang Wei ◽  
Chuan Zhou ◽  
Min Yuan ◽  
Yuyang Miao ◽  
Xiaoe Zhao ◽  
...  

In vitro maturation (IVM) of oocytes is an important assisted reproductive technology for infertility treatment and livestock breeding programs. Because of asynchronous nuclear and cytoplasmic maturation, the developmental competence of oocytes matured in vitro is compromised. C-Type natriuretic peptide (CNP), which has been proved to be an inhibitor of oocyte maturation, provides a new alternative to optimise synchronisation of nuclear and cytoplasmic maturation and improve developmental capacity of immature oocytes in vitro. To investigate the effect of temporary meiotic arrest mediated by CNP on maturation and subsequent development of immature oocytes, immature mouse oocytes from small antral follicles were temporarily arrested in meiosis by CNP (0, 5, 10 and 50 nM) for 24 h and then matured for 16 h. CNP treatment significantly increased the oocyte maturation rate from less than half to above 80%. After IVF, temporary meiotic arrest mediated by 10 and 50 nM CNP significantly improved fertilisation and blastocyst rate of oocytes matured in vitro up to approximately 55% and 30% respectively. Moreover, this positive effect of CNP was attributed, in part, to an increase in the number of mature oocytes with aligned chromosomes and a normal spindle. The present findings indicate the potential to use CNP to improve the efficiency of oocyte IVM.

2009 ◽  
Vol 21 (1) ◽  
pp. 217
Author(s):  
T. Wakai ◽  
N. Zhang ◽  
R. A. Fissore

Numerous studies have demonstrated that postovulatory aging of oocytes prior to fertilization has detrimental effects on oocyte quality and developmental competence. Oocyte aging is accompanied by abnormal oocyte activation and subsequent development, suggesting a disruption of Ca2+ oscillations after fertilization. The inositol 1,4,5-trisphosphate receptor type 1 (IP3R1) in mammals is responsible for the majority of Ca2+ release during fertilization (Miyazaki S et al. 1993 Dev. Biol.). Previously, we reported that phosphorylation of IP3R1 at an MPM-2 epitope may play an important role in facilitating the induction of Ca2+ oscillations at the MII stage (Lee B et al. 2006 Development), indicating that IP3R1 phosphorylation may be a good indicator of the health of the oocyte. However, few studies have investigated the alteration of the Ca2+ signaling and IP3R1 function associated with oocyte aging. On the other hand, a previous report showed that caffeine increased MPF activity and suppressed fragmentation after parthenogenetic activation of aged oocytes (Kikuchi K et al. 2000 Biol. Reprod.). Therefore, the purpose of the present study was to examine whether and how Ca2+ oscillatory activity changes during oocyte aging and to test if caffeine prevents the negative effects of oocyte aging. MII mouse oocytes were collected 14 h after hCG injection and cultured in vitro for 8, 24 or 48 h with or without caffeine (5 or 10 mm). Oocyte quality was assessed by the occurrence of spontaneous fragmentation, monitoring of Ca2+ oscillations after exposure to 10 mm strontium chloride, Western blot analysis of IP3R1 phosphorylation and immunostaining of IP3R1. In oocytes in vitro aged for 8 h, the duration of the first Ca2+ rise was significantly decreased compared with fresh MII oocytes, although this reduction was not observed in MII oocytes treated with 5 mm caffeine. The phosphorylation of IP3R1 at the MPM-2 epitope was slightly decreased during oocyte aging in both caffeine and noncaffeine treatment. Importantly, whereas IP3R1 in MII oocytes treated for 8 h with 5 mm caffeine displayed the typical cortical cluster organization, IP3R1 in aged oocytes without caffeine became dispersed in the cytoplasm. In addition, caffeine significantly suppressed the spontaneous fragmentation that is normally observed by 48 h of in vitro culture. These results suggest that the Ca2+ oscillatory activity is compromised during oocyte aging and caffeine prevents the loss of integrity of Ca2+ signaling possibly by keeping the cortical distribution of IP3R1.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Zhenwei Jia ◽  
Xueli Wang

Abstract The present study aimed to evaluate the effects of C-type natriuretic peptide (CNP) on meiotic arrest and developmental competence of bovine oocyte derived from follicles of different sizes. Collected immature cumulus-oocyte complexes from small follicles (< 3 mm) and medium follicles (3–8 mm) were cultured for 6 h in basal medium supplementated without or with 200 nM CNP. We observed that CNP effectively sustained meiotic arrest at germinal vesicle stage in in vitro cultured bovine oocytes from follicles of different sizes. Moreover, CNP treatment significantly improved the levels of cGMP in both cumulus cells and oocytes, as well as the levels of cAMP in oocytes regardless of follicle size. Based on the above results, we tested the effect of a novel in vitro maturation (IVM) system based on CNP-pretreatment, including a pre-IVM phase for 6 h using 200 nM CNP, followed by a extended IVM phase for 28 h, on developmental competence of bovine oocyte derived from small follicles (< 3 mm) and medium follicles (3–8 mm) compared to standard IVM system. The results showed that athough the novel IVM system based on CNP-pretreatment enhanced the developmental potencial of oocytes obtained from large follicles, but had no effect on the developmental comptence of oocytes obtained from small follicles.


Reproduction ◽  
2019 ◽  
Vol 158 (6) ◽  
pp. 543-554
Author(s):  
Hae-Jun Yang ◽  
Sanghoon Lee ◽  
Bo-Woong Sim ◽  
Pil-Soo Jeong ◽  
Seon-A Choi ◽  
...  

The developmental competence of in vitro-matured oocytes is still lower than that of the in vivo-matured oocytes due to precocious meiotic resumption and inappropriate cytoplasmic maturation. Although numerous efforts have been attempted to accomplish better in vitro maturation (IVM) condition, only limited progress has been achieved. Thus, a current study was conducted to examine the effects of 6-diazo-5-oxo-l-norleucine (DON, an inhibitor of hyaluronan synthesis) during the first half period of IVM on nuclear/cytoplasmic maturation of porcine oocytes and subsequent embryonic development. Based on the observation of the nucleus pattern, metaphase II (MII) oocyte production rate in 1 µM DON group was significantly higher than other groups at 44 h of IVM. The 1 µM of DON was suggested to be optimal for porcine IVM and was therefore used for further investigation. Meiotic arrest effect of DON was maximal at 6 h of IVM, which was supported by the maintenance of significantly higher intra-oocyte cAMP level. In addition, increased pERK1/2 levels and clear rearrangement of cortical granules in membrane of MII oocytes matured with DON provided the evidence for balanced meiosis progression between nuclear and cytoplasmic maturation. Subsequently, DON significantly improved blastocyst formation rate, total cell numbers, and cellular survival in blastocysts after parthenogenetic activation, in vitro fertilization, and somatic cell nuclear transfer. Altogether, our results showed for the first time that 1 µM DON can be used to increase the yield of developmentally competent MII oocytes by synchronizing nuclear/cytoplasmic maturation, and it subsequently improves embryo developmental competence.


2010 ◽  
Vol 9 (4) ◽  
pp. 211-215 ◽  
Author(s):  
Afsaneh Golkar-Narenji ◽  
Hussein Eimani ◽  
Firooz Samadi ◽  
Saeed Hasani ◽  
Abdol-Hossein Shahverdi ◽  
...  

2014 ◽  
Vol 26 (1) ◽  
pp. 197
Author(s):  
K. Saeki ◽  
D. Iwamoto ◽  
S. Taniguchi ◽  
M. Kishi ◽  
N. Kato

During bovine oocyte maturation, a lower density of cumulus cells surrounding oocytes reduces the developmental competence of the oocytes after IVF. Adding more cumulus cells (Hashimoto et al. 1998) rescues the developmental competence of the corona-enclosed oocytes. In this study, we examined the effects of poly(dimethylsiloxane) (PDMS) microwells (MW) for bovine oocyte maturation on the developmental competence of the oocytes following IVF. In experiment 1, MW were produced by making holes on 0.5-mm-thick PDMS plates using a 0.5-mm-diameter biopsy punch. The punched plates were placed on the bottoms of culture dishes. Bovine cumulus oocytes complexes (COC) were collected from slaughterhouse ovaries. Cumulus layers were removed from COC to prepare corona-enclosed oocytes (CEO) and denuded oocytes (DO). Then, COC, CEO, or DO were individually matured in single MW for 24 h at 39°C under 5% CO2 in air with high humidity. Ten oocytes of each group were matured in 50-μL droplets of maturation medium (group culture, GC) as controls. Maturation medium was TCM-199 supplemented with 10% FCS, 0.02 AU mL–1 FSH, and 1 μg mL–1 E2. The matured oocytes were fertilized with frozen–thawed spermatozoa. The embryos were cultured in CR1aa medium for 168 h under 5% CO2, 5% O2 and 90% N2 with high humidity. In experiment 2, effects of depth of MW for maturation on subsequent development following IVF were examined. Microwells were produced by making 0.5-mm-diameter holes on 0.5- or 1.5-mm-thick PDMS plates. Then, COC or CEO were individually matured in the MW for 24 h. Matured oocytes were fertilized in vitro and cultured for 168 h. Oocytes that were matured by GC were used as controls. In experiment 1(N = 4), rates of maturation (76–100%, n = 26 to 38), normal fertilization (53–70%, n = 44 to 49), and cleavage (61–77%, n = 114 to 117) were not different among all groups (P > 0.05; Fisher's PLSD test following ANOVA). Blastocyst rates were the same (P > 0.05) for COC matured in MW (50%) and by GC (43%). The rate for CEO that matured in MW (46%) tended to be higher (P = 0.061) than the rate for CEO that matured by GC (31%), and was comparable to the rate for COC matured by GC (43%). The blastocyst rates for DO that matured in MW and by GC were low (6%). In experiment 2 (N = 3), rates of maturation (86–100%, n = 13 to 28), normal fertilization (60–78%, n = 22 to 40), and cleavage (67–73%, n = 85 to 90) were not different among all groups (P > 0.05). However, the blastocyst rate for COC that matured in 1.5-mm-deep MW (53%) was significantly higher than the rates for COC that matured in 0.5-mm-deep MW (38%) and by GC (31%; P < 0.05). The results indicate that the developmental competence of oocytes that matured individually in PDMS MW was greater than that of oocytes that matured by GC. The deeper (1.5 mm) MW were found to be more effective for oocyte maturation than shallow (0.5 mm) MW and GC. The MW might increase density of cumulus cells surrounding oocytes, and the high cell-density enhanced the developmental competence of the oocytes.


2015 ◽  
Vol 27 (1) ◽  
pp. 226 ◽  
Author(s):  
S. Uzbekova ◽  
L. Sanchez-Lazo ◽  
A. Desmachais ◽  
V. Maillard ◽  
S. Elis

Oocyte maturation relies on energy from different nutrients, including fatty acids (FA). Cumulus cells (CC) are metabolically coupled with enclosed oocyte and active FA metabolism occurs in both compartments. Excess of lipids in oocyte environment alters its developmental competence. Lipid droplets (LD), mainly composed of triacylglycerides (TG), are formed inside of CC and in oocyte to store lipids. Liberation of free FA from TG requires lipolysis, which is catalyzed by lipases and involves FA-binding proteins (FABP) and perilipins (PLIN), which interact at the surface of LD as shown in lipogenic tissues. The objective was to elucidate the main factors involved in lipolysis in bovine cumulus-oocyte complex (COC) during oocyte maturation. Gene expression before and after maturation was analysed in CC by microarray hybridization and validated by real time RT-PCR; proteins were detected by Western blot and immunofluorescence. For statistics, ANOVA and Mann-Whitney (M-W) tests were used. In CC, adipose triglyceride lipase PNPLA2, lipoprotein lipase LPL, and monoacylglycerol lipase ABHD6 showed the highest mRNA expression level among 7 detected lipases. Both PLIN5 and PLIN2 were the most abundant perilipins, and among 8 FA-binding proteins, FABP3 and FABP5 were predominant. During in vitro maturation (IVM), expression of most of these genes increased at 6 h of IVM (P < 0.05, ANOVA) in CC. At that time, germinal vesicle breakdown occurred in enclosed oocytes and hyaluronan synthase HAS2, involved in the extra-cellular matrix formation, was upregulated in CC. The most upregulated genes after 18 h of IVM in CC were ABDH6 (48.5-fold as compared to immature, P < 0.01, M-W), FABP3 (16.6-fold, P < 0.01, M-W), and PLIN2 (5.5-fold, P < 0.05, M-W). Expression of all of these lipolysis-related genes was also detected in the oocytes. At the protein level, PLIN2 was mainly localised in the cytoplasmic LD, both in CC and in the oocyte. In CC, FABP3 was detected in the cytoplasm, whereas in oocyte it was also localised to the germinal vesicle of immature oocytes and closely to the chromosomes during the first meiotic division. In addition, active phosphorylated hormone sensitive lipase HSL was always detected in CC and in mature oocytes, but not in immature oocytes. All these data demonstrate that lipolysis occurs both in CC and in the oocyte during maturation. Lipolysis may be necessary to maintain cell energy homeostasis by regulating intracellular concentration of free FA. Moreover, CC were already described to store the excess FA from follicular fluid in order to protect the oocyte. Our data corroborate the essential role of CC in oocyte survival through controlling FA metabolism inside the COC. Active lipolysis may therefore be required to reduce lipid storages as well as to produce energy necessary for oocyte meiosis progression and extracellular matrix secretion by CC in order to prepare COC for further fertilization.This work was supported by INRA, ANR (OSCILE project) and European subvention FP7-KBBE-2012–6 (FECUND project).


2005 ◽  
Vol 17 (2) ◽  
pp. 271
Author(s):  
L. Campos-Chillon ◽  
T. Suh ◽  
E. Carnevale ◽  
G. Seidel

Maintaining immature bovine oocytes at the germinal vesicle stage by inhibiting M-phase promoting factor (MPF) activity is a reversible process when using roscovitine, and this can improve cytoplasmic maturation in vitro. However, optimum meiotic arrest times and subsequent IVM times have not been determined, so we evaluated the developmental competence of oocytes in relation to these times. Two by two factorial treatments consisting of 2 arrest times (8 h, 16 h) and 2 subsequent IVM times (16 h, 22 h) plus a control were replicated 6 times in this study. Semen from two bulls was used three times. Chemically defined media (CDM) were used throughout (Olson and Seidel 2000 J. Anim. Sci. 78, 152–157). Slaughterhouse-derived oocytes were arrested in meiosis in 1 mL of CDM-M without any hormones, but containing 50 μM roscovitine and 0.5% fatty acid-free (FAF)-BSA under 5% CO2 in air at 38.5°C. After 8 or 16 h of meiotic arrest, oocytes were washed and matured in 1 mL of CDM-M containing 0.5% FAF-BSA, 2 mM glucose, 50 ng/mL EGF, 15 ng/mL NIDDK-oFSH-20, 1 μg/mL USDA-LH-B-5, 1 μg/mL E2, and 0.1 mM cysteamine for 16 or 22 h under 5% CO2 in air at 38.5°C. Oocytes for the control group were matured in 1 mL of the CDM-M with hormones for 22 h. Ten oocytes from each group were fixed after IVM, stained with orcein, and evaluated for maturation to MII. For fertilization, motile sperm recovered from frozen-thawed semen were co-incubated for 18–20 h with ∼20 oocytes/group at a final sperm concentration of 0.5 × 106 sperm/mL in F-CDM. Presumptive zygotes were cultured in 0.5 mL of CDM-1 for 2.5 days and then in CDM-2 for 5.5 days in 5% CO2, 5% O2, 90% N2 in a humidified incubator at 39°C. Cleavage rates were evaluated after culture in CDM-1. Blastocyst rate, blastocyst stage (5 = early, 6 = full, 6.5 = expanding, 7 = expanded, 7.5 = hatching, 8 = hatched), and embryo quality (1 = excellent, 2 = good, 3 = fair, 4 = poor) were evaluated after CDM-2. Data were subjected to ANOVA; the arc sin transformation was used for percentage data, and least-squares means are presented. There were no significant differences in % cleavage (Cle), cell stage, or blastocyst quality among treatments (P > 0.1). However, meiotic arrest of oocytes for 16 h and subsequent IVM for 16 h improved embryo development to blastocysts compared to other roscovitine treatments (Table 1, P < 0.05). A bull effect for % blastocysts was observed, 19.9% and 25.2% for bulls 1 and 2, respectively (P < 0.08). Blastocyst production was improved by shortening oocyte maturation time from 22 to 16 h, when meiotic progression was previously inhibited for 16 h with roscovitine. Table 1. Effect of meiotic arrest and IVM times on oocyte maturation and embryo development


PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e6930
Author(s):  
Yan Zhang ◽  
Jing Guo ◽  
Xiao Wei Nie ◽  
Zi Yue Li ◽  
Yu Meng Wang ◽  
...  

Background In vitro maturation (IVM) of oocytes has been widely used in the field of assisted reproductive technology. However, oocytes can be injured by oxidative stress during the process of IVM. Methods The present study was designed to evaluate the influences of rosmarinic acid (RA) on the IVM of porcine oocytes and the subsequent development of early-stage embryos as well as its underlying mechanisms. Various concentrations of RA (5 µM, 10 µM, and 25 µM) were treated with porcine oocyte maturation medium during the period of IVM. Results and Discussion The results showed that 5 µM RA treatment during the period of porcine oocyte IVM improves blastocyst quality and hatching ability after parthenogenetic activation. Furthermore, the presence of RA during the period of IVM dramatically improved the total number of cells after somatic cell nuclear transfer compared to the number of cells in the control group. Notably, RA treatment during the period of porcine oocyte IVM decreased intracellular reactive oxygen species generation not only in oocytes but also in cumulus cells. Further analysis showed that the intracellular free thiols levels in the oocytes were enhanced by treatment with RA during the period of porcine oocyte IVM compared to the free thiols levels in the control groups. These results indicate that RA improves the developmental competence of porcine oocytes during the IVM period by attenuating oxidative stress.


Sign in / Sign up

Export Citation Format

Share Document