272 A NEW APPROACH TO IN VITRO MATURATION (IVM) AND EMBRYO IN VITRO PRODUCTION: INDUCED IVM SUBSTANTIALLY IMPROVES EMBRYO YIELD AND PREGNANCY OUTCOMES

2010 ◽  
Vol 22 (1) ◽  
pp. 293
Author(s):  
R. B. Gilchrist ◽  
F. K. Albuz ◽  
J. G. Thompson

Oocyte in vitro maturation (IVM) is the rate-limiting step in the in vitro production (IVP) of embryos. Oocyte maturation in vivo is a highly orchestrated, induced process, whereby cAMP-mediated meiotic arrest is overridden by the gonadotrophin surge prior to ovulation. However, aspirated oocytes resume maturation spontaneously compromising developmental competence. Hence, we hypothesized that establishing an induced system in vitro would synchronize oocyte-somatic cell communication leading to improved oocyte quality. Abattoir-collected bovine or 129/Sv mouse oocytes were treated for the first 1 to 2 h in vitro (pre-IVM) with the adenylate cyclase activator forskolin (100 μM, 50 μM, respectively) and a nonspecific phosphodiesterase (PDE) inhibitor, IBMX (500 μM, 50 μM), which substantially increased cumulus-oocyte complex (COC) cAMP (bovine, 180 v. 2 fmol/COC, treated v. control; P < 0.001). To maintain oocyte cAMP levels and prevent precocious oocyte maturation, IVM media (VitroMat + BSA) contained an oocyte-specific (type 3) PDE inhibitor, cilostamide (20 μM, 0.1 μM), plus FSH to induce maturation. The net effect of this system (induced-IVM) was to increase oocyte-cumulus cell gap-junctional communication (bovine: 1000 ± 148 v. 340 ± 73 unit, treated v. control; P < 0.05) and to slow meiotic progression through prophase I to metaphase II, extending the normal IVM interval (bovine: 30 v. 24 h, mouse: 22 v. 18 h; treated v. control). FSH was required to complete maturation and FSH-induced maturation was prevented by an epidermal growth factor receptor inhibitor, AG1478 (2.5 μM), demonstrating induced oocyte maturation functions via secondary autocrine signaling within the cumulus cell compartment. These effects on COC functions had profound consequences for oocyte developmental potential. In completely serum-free bovine IVP, induced-IVM more than doubled blastocyst yield (69 v. 27%, treated v. control; P < 0.05) and improved blastocyst quality (186 v. 132 blastomeres). To achieve these rates, the pre-IVM phase, the modified IVM conditions, and delayed IVF were all required. Adapting the system to the mouse, induced-IVM increased blastocyst rate (86 v. 55%, treated v. control; P < 0.05), implantation rate (51 v. 25%; P < 0.01), fetal survival rate (29 v. 5%; P < 0.01) and fetal weight (0.9 v. 0.5 g; P < 0.01). All these embryonic and fetal outcomes in mice were equivalent (P > 0.05) using induced-IVM to levels obtained from in vivo-matured control oocytes (conventional IVF). Data were analyzed by ANOVA. In conclusion, induced-IVM mimics some of the characteristics of oocyte maturation in vivo and substantially improves oocyte developmental outcomes in 2 disparate mammalian species. Adaption of this new approach to clinical/field conditions should lead to new opportunities for a wide range of reproductive biotechnologies. Such a notable increase in IVM efficiency could see IVP as the preferred embryo production technology in future livestock artificial breeding programs. Funded by an Australian Research Council Linkage Grant and Cook Australia. Thanks to M. Sasseville, M. Lane, and D. T. Armstrong.

2017 ◽  
Vol 29 (1) ◽  
pp. 202 ◽  
Author(s):  
A. Lange-Consiglio ◽  
C. Perrini ◽  
P. Esposti ◽  
F. Cremonesi

The in vitro maturation of canine oocyte is problematic because it is difficult to reproduce the oviducal microenvironment where the in vivo maturation occurs. Because cells are able to communicate with each other by paracrine action, oviducal cells could be in vitro cultivated to obtain the conditioned medium (CM) consisting of soluble factors and microvesicles (MV), which represent a carrier for nonsoluble molecules including microRNA. The aim of the present work was to investigate the effect of the addition of CM or MV, secreted by oviducal cells, to the canine in vitro maturation medium. To generate CM, cells from oviducts of 3 animals in late oestrus were cultured for 5 days at 38.5°C in a humidified atmosphere of 5% CO2. Supernatants were collected, pooled, centrifuged at 2500 × g, and stored at −80°C. Microvesicles were obtained by ultracentrifugation of CM at 100,000 × g for 1 h at 4°C and measured for concentration and size by a Nanosight instrument. Ovaries were obtained from 50 healthy domestic bitches (1–4 years old) of different breeds that underwent ovariectomy regardless of the oestrous cycle. Cumulus-oocyte complexes were released by slicing the ovarian cortex with a scalpel blade, and only Grade 1 cumulus-oocyte complexes (darkly granulated cytoplasm and surrounded by 3 or more compact cumulus cell layers) 110 to 120 µm in diameter were selected for culture. Maturation was performed at 38.5°C in a humidified atmosphere of 5% CO2 and 5% of O2 in bi-phasic systems: 24 h in SOF with 5.0 μg mL−1 of LH followed by 48 h in SOF supplemented with 10% of oestrous bitch serum and 10% CM or 50, 75, 100, or 150 × 106 MV mL−1 labelled with PKH-26. Control was the same medium without CM or MV. Oocytes were observed under a fluorescent microscope to detect metaphase II (MII), by Hoechst staining, and the incorporation of MV. Statistical analysis was performed by chi-square test. Results show that canine oviducal cells secreted MV of 234 ± 23 nm in size, underling that these MV fall within the shedding vesicles category. The incorporation of labelled MV occurred at first in cumulus cells, at 48 h of maturation, and then, at 72 h, in oocyte cytoplasm. These MV had a positive effect on maturation rate (MII) at the concentration of 75 and 100 × 106 MV mL−1 compared with CM and control (20.34 and 21.82 v. 9.09 and 3.95%, respectively). The concentration of 150 × 106 MV mL−1 provided only 9.26% of MII. To understand the role of MV, we assessed the expression of 3 microRNA (miRNA-30b, miR-375, and miR-503) that are involved in some key pathways (WNT, MAPK, ERbB, and TGFβ) regulating follicular development and meiotic resumption. The lower rate of MII with the higher concentration of MV is possibly due to the high level of miR-375, which recent literature shows to suppress the TGFβ pathway, leading to impaired oocyte maturation. In conclusion, the oviducal MV, or specific microRNA, are involved in cellular trafficking during oocyte maturation, and their possible use in vitro could facilitate the exploitation of canine reproductive biotechnologies.


Author(s):  
Alan da Silva LIRA ◽  
Ricardo de Macedo CHAVES ◽  
Felipe de Jesus MORAES JUNIOR ◽  
Sergio Henrique COSTA JUNIOR ◽  
Brenda Karine Lima do AMARAL ◽  
...  

ABSTRACT We aimed to assess the effects of melatonin in the in vitro production of bovine embryos. Our experiment was conducted at the Laboratório de Reprodução Animal of the Universidade Estadual do Maranhão. The cumulus-oocyte complexes (COCs) were distributed among treatments at concentrations of 0, 10-1, 10-3 and 10-5 µMol/L melatonin. Our experiment was further divided into two: the first was to assess the effect of different concentrations of melatonin (treatments) on the maturation rate of COCs, and the second was to assess the effects of melatonin treatments on the in vitro production of bovine embryos. The results from the first experiment demonstrated no significant difference between the in vitro maturation rate of the cultivated COCs in treatments with melatonin. In the second experiment, however, melatonin treatments yielded statistically higher cleavage, morula and blastocyst rates in the 10-5 µM group (52.9%, 52.9%, and 35.3%, respectively), and lower rates in the 10-1 µM group (19.5%, 19.5% and 7.8%, respectively), compared to the others. The control group (no melatonin) and the 10-3 µM group showed similar results. We concluded that supplementation of melatonin in the in vitro maturation medium resulted in no improvement in the oocyte maturation rate, but in the in vitro production of embryos at different concentrations, the 10-5 µM group displayed better results, but with no improvement in the variables (P < 0.05).


2011 ◽  
Vol 23 (1) ◽  
pp. 23 ◽  
Author(s):  
Robert B. Gilchrist

The last 5–10 years of research in ovarian and oocyte biology has delivered some major new advances in knowledge of the molecular and cellular processes regulating oocyte maturation and oocyte developmental competence. These new insights include, among others: (1) the knowledge that oocytes regulate granulosa and cumulus cell differentiation, ovulation rate and fertility via the secretion of soluble paracrine growth factors; (2) new perspectives on the participation of cyclic nucleotides, phosphodiesterases and gap junctions in the regulation of oocyte meiotic arrest and resumption; and (3) the new appreciation of the mechanisms of LH-induced oocyte maturation and ovulation mediated by the follicular cascade of epidermal growth factor (EGF)-like peptides, the EGF receptor and their intracellular second messengers. These recent insights into oocyte–follicle cell interactions provide opportunities for the development of new approaches to oocyte in vitro maturation (IVM). Laboratory IVM methodologies have changed little over the past 20–30 years and IVM remains notably less efficient than hormone-stimulated IVF, limiting its wider application in reproductive medicine and animal breeding. The challenge for oocyte biologists and clinicians practicing IVM is to modernise clinical IVM systems to benefit from these new insights into oocyte–follicle cell interactions in vivo.


2016 ◽  
Vol 5 (03) ◽  
pp. 4927 ◽  
Author(s):  
Shubhi Srivastava ◽  
Paul A. K.

Plant associated microorganisms that colonize the upper and internal tissues of roots, stems, leaves and flowers of healthy plants without causing any visible harmful or negative effect on their host. Diversity of microbes have been extensively studied in a wide variety of vascular plants and shown to promote plant establishment, growth and development and impart resistance against pathogenic infections. Ferns and their associated microbes have also attracted the attention of the scientific communities as sources of novel bioactive secondary metabolites. The ferns and fern alleles, which are well adapted to diverse environmental conditions, produce various secondary metabolites such as flavonoids, steroids, alkaloids, phenols, triterpenoid compounds, variety of amino acids and fatty acids along with some unique metabolites as adaptive features and are traditionally used for human health and medicine. In this review attention has been focused to prepare a comprehensive account of ethnomedicinal properties of some common ferns and fern alleles. Association of bacteria and fungi in the rhizosphere, phyllosphere and endosphere of these medicinally important ferns and their interaction with the host plant has been emphasized keeping in view their possible biotechnological potentials and applications. The processes of host-microbe interaction leading to establishment and colonization of endophytes are less-well characterized in comparison to rhizospheric and phyllospheric microflora. However, the endophytes are possessing same characteristics as rhizospheric and phyllospheric to stimulate the in vivo synthesis as well as in vitro production of secondary metabolites with a wide range of biological activities such as plant growth promotion by production of phytohormones, siderophores, fixation of nitrogen, and phosphate solubilization. Synthesis of pharmaceutically important products such as anticancer compounds, antioxidants, antimicrobials, antiviral substances and hydrolytic enzymes could be some of the promising areas of research and commercial exploitation.


2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
I Viran. . Klun ◽  
J Bedenk ◽  
N Jancar

Abstract Study question Do different types of cancer affect the success of oocyte maturation in vitro compared to infertile women included in the in vitro fertilization (IVF) program? Summary answer Cancer does not adversely affect oocyte maturation in vitro, with the exception of breast cancer, compared to infertile women in the in vitro fertilization program. What is known already Vitrification and storage of oocytes in liquid nitrogen is one of the real options for maintaining reproductive function in cancer patients. Despite careful hormonal stimulation of the ovaries, however, the proportion of oocytes is immature and lost to the patient. In vitro maturation of oocytes can play an important role in resolving immature oocytes and increasing the chances of conception in cancer patients. Moreover, it can mean a safe way to store oocytes when ovarian hormonal stimulation could worsen the disease. Therefore, the aim of this study was to determine whether different types of cancer affect oocyte in vitro maturation. Study design, size, duration After ovarian stimulation in 18 cancer patients, the number and maturity of oocytes were compared to 21 infertile patients in the IVF program over a three-year period. In both groups, 119 germinal vesicle-GV oocytes were matured in vitro to compare the maturation rate. After IVF in a subset of 17 infertile patients, the fertilization of in vitro and in vivo matured oocytes was compared in the same cycles. The procedure was considered in cancer patients. Participants/materials, setting, methods In this prospective study, forty-five GV oocytes in cancer patients and 74 GV oocytes in infertile patients underwent in vitro maturation procedure. Each oocyte was matured in vitro in the MediCult IVM System by conditioning in LAG medium and maturation for up to 28 hours in IVM medium with added hormones FSH and hCG, in coculture with cumulus cells from mature oocytes in the same patients. Oocytes were fertilized by intracytoplasmic sperm injection (ICSI). Main results and the role of chance After controlled ovarian hormonal stimulation, 198 oocytes were retrieved in cancer patients and 259 oocytes in infertile women and there were no significant differences in the number of retrieved oocytes, proportion of degenerated oocytes and proportion of GV oocytes. In cancer patients, the proportion of oocytes that matured in vitro was lower than in infertile patients (66.0 vs. 80.0%), but the difference was not significant. Among cancer patients, the oocyte maturation rate tended to be lower in patients with breast cancer than in patients with other cancers (54.5% vs. 81.2%; difference not significant). However, in patients with breast cancer, significantly fewer oocytes matured in vitro than in infertile patients (54.5% vs. 80.0%; P &lt; 0.05, Chi-Square test) even though they tended to be younger (29.3 ± 7.4 vs. 33.4 ± 5.0 years; non-significant difference). After in vitro maturation, there was a 13% increase in mature oocyte yield in cancer patients and a 20.1% increase in infertile women with no significant difference observed. After ICSI in a subset of infertile women, there was approximately the same fertilization rate between oocytes matured in vitro and in vivo (55.1% vs. 57.0%) in the same cycles. Limitations, reasons for caution For ICSI in oocytes matured in vitro, we had to use semen collected the day before, while oocytes matured in vivo were fertilized with fresh semen in the same cycle. Therefore, we could not compare the development of embryos in both groups. Wider implications of the findings: In vitro maturation of oocytes in connection with their vitrification or vitrification of embryos after their fertilization appears to be a valuable way to maintain the fertility of young cancer patients, but a worse outcome is expected in breast cancer patients. Trial registration number National Medical Ethical Committee Approval, No. 0120–222/2016–2; KME 115/04/16.


2020 ◽  
Vol 56 (7) ◽  
pp. 577-584
Author(s):  
Emma Hicks ◽  
Miranda Mentler ◽  
Haley A. Arena ◽  
Jaelyn Z. Current ◽  
Brian D. Whitaker

2018 ◽  
Vol 30 (12) ◽  
pp. 1728 ◽  
Author(s):  
M. Arias-Álvarez ◽  
R. M. García-García ◽  
J. López-Tello ◽  
P. G. Rebollar ◽  
A. Gutiérrez-Adán ◽  
...  

The developmental competence of in vitro maturation (IVM) oocytes can be enhanced by antioxidant agents. The present study investigated, for the first time in the rabbit model, the effect of adding α-tocopherol (0, 100, 200 and 400 µM) during IVM on putative transcripts involved in antioxidant defence (superoxide dismutase 2, mitochondrial (SOD2), glutathione peroxidase 1 (GPX1), catalase (CAT)), cell cycle regulation and apoptosis cascade (apoptosis tumour protein 53 (TP53), caspase 3, apoptosis-related cysteine protease (CASP3)), cell cycle progression (cellular cycle V-Akt murine thymoma viral oncogene homologue 1 (AKT1)), cumulus expansion (gap junction protein, alpha 1, 43 kDa (GJA1) and prostaglandin-endoperoxide synthase 2 (prostaglandin G/H synthase and cyclo-oxygenase) (PTGS2)) and metabolism (glucose-6-phosphate dehydrogenase (G6PD)). Meiotic progression, mitochondrial reallocation, cumulus cell apoptosis and the developmental competence of oocytes after IVF were also assessed. Expression of SOD2, CAT, TP53, CASP3 and GJA1 was downregulated in cumulus–oocyte complexes (COCs) after IVM with 100 μM α-tocopherol compared with the group without the antioxidant. The apoptotic rate and the percentage of a non-migrated mitochondrial pattern were lower in COCs cultured with 100 μM α-tocopherol, consistent with better-quality oocytes. In fact, early embryo development was improved when 100 μM α-tocopherol was included in the IVM medium, but remained low compared with in vivo-matured oocytes. In conclusion, the addition of 100 μM α-tocopherol to the maturation medium is a suitable approach to manage oxidative stress and apoptosis, as well as for increasing the in vitro developmental competence of rabbit oocytes.


Sign in / Sign up

Export Citation Format

Share Document