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Leal GR, Oliveira TDA, de Paula Guimarães MP, Correia LFL, Vasconcelos EM, Souza-Fabjan JMG. Lipid modulation during IVM increases the metabolism and improves the cryosurvival of cat oocytes. Theriogenology 2024; 214:33-42. [PMID: 37839095 DOI: 10.1016/j.theriogenology.2023.10.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2023] [Revised: 09/15/2023] [Accepted: 10/03/2023] [Indexed: 10/17/2023]
Abstract
This study investigated the time course of lipid accumulation during IVM and assessed the role of lipid modulators added during IVM on lipid content, nuclear maturation, oxidative stress, mitochondrial activity, gene expression, and cryosurvival of cat oocytes. First, the lipid content of immature COCs was compared to those subjected to different IVM duration times (24, 28, and 32 h). Then, the lipid content was investigated after the use of different lipid modulators [conjugated linoleic acid (CLA), forskolin (FSK), l-carnitine (LC)]. Subsequently, both the CONTROL group and MIX 18 (CLA+FSK+LC) were compared regarding nuclear maturation, mitochondrial activity, reactive oxygen 19 species (ROS), and glutathione (GSH) levels, to the expression of SDHA, GDF9, BMP15, ZAR-1, 20 PRDX1, SIRT1, and SIRT3 genes (normalized by ACTB and YWHAZ genes); and to vitrification and 21 post-warming viability assessment. When not using any lipid modulator, an increase (P < 0.05) in lipid content could be observed after 28 h of IVM. The MIX group showed the greatest (P < 0.05) reduction in oocyte lipid content after 28 h of IVM. No difference (P > 0.05) was observed in the MII rate in the CONTROL (45%) and MIX (41%) groups and in mitochondrial activity ((1.00 ± 0.35 A U vs 1.19 ± 0.14 A U). Although ROS and GSH levels were higher (P < 0.05) in MIX than in CONTROL, the redox balance (ROS/GSH) was greater (P < 0.05) in the latter (C:1.00 ± 0.20b vs M:0.26 ± 0.06 a A.U). The GDF9, HSP70, PRDX1, and SIRT1 transcripts were downregulated (P < 0.05) in MIX-oocytes, compared to the CONTROL. After vitrification, MIX (74%) presented a higher (P < 0.05) viability compared to control (53%). In conclusion, MIX can reduce the total lipid content and improve viability after cryopreservation, however, it seems to affect the oocyte metabolism in a way that still needs to be better understood in the cat biological model.
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Affiliation(s)
- Gabriela Ramos Leal
- Universidade Federal Fluminense (UFF), Faculdade de Medicina Veterinária, Vital Brazil Filho St., 64, 24230-340, Niterói, Rio de Janeiro, Brazil.
| | - Thais de Almeida Oliveira
- Universidade Federal Fluminense (UFF), Faculdade de Medicina Veterinária, Vital Brazil Filho St., 64, 24230-340, Niterói, Rio de Janeiro, Brazil
| | - Mariana Pedrosa de Paula Guimarães
- Universidade Federal Fluminense (UFF), Faculdade de Medicina Veterinária, Vital Brazil Filho St., 64, 24230-340, Niterói, Rio de Janeiro, Brazil
| | - Lucas Francisco Leodido Correia
- Universidade Federal Fluminense (UFF), Faculdade de Medicina Veterinária, Vital Brazil Filho St., 64, 24230-340, Niterói, Rio de Janeiro, Brazil
| | - Erlandia Márcia Vasconcelos
- Universidade Federal Fluminense (UFF), Faculdade de Medicina Veterinária, Vital Brazil Filho St., 64, 24230-340, Niterói, Rio de Janeiro, Brazil
| | - Joanna Maria Gonçalves Souza-Fabjan
- Universidade Federal Fluminense (UFF), Faculdade de Medicina Veterinária, Vital Brazil Filho St., 64, 24230-340, Niterói, Rio de Janeiro, Brazil.
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Lee PC, Stewart S, Amelkina O, Sylvester H, He X, Comizzoli P. Trehalose delivered by cold-responsive nanoparticles improves tolerance of cumulus-oocyte complexes to microwave drying. J Assist Reprod Genet 2023:10.1007/s10815-023-02831-x. [PMID: 37261586 PMCID: PMC10371938 DOI: 10.1007/s10815-023-02831-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Accepted: 05/18/2023] [Indexed: 06/02/2023] Open
Abstract
PURPOSE Trehalose is a non-permeable protectant that is the key to preserve live cells in a dry state for potential storage at ambient temperatures. After intracellular trehalose delivery via cold-responsive nanoparticles (CRNPs), the objective was to characterize the tolerance of cat cumulus-oocyte complexes (COCs) to different levels of microwave-assisted dehydration. METHODS Trehalose was first encapsulated in CRNPs. After exposure to trehalose-laden CRNPs, different water amounts were removed from cat COCs by microwave drying. After each dehydration level, meiotic and developmental competences were evaluated via in vitro maturation, fertilization, and embryo culture. In addition, expressions of critical genes were assessed by quantitative RT-PCR. RESULTS CRNPs effectively transported trehalose into COCs within 4 h of co-incubation at 38.5 °C followed by a cold-triggered release at 4 °C for 15 min. Intracellular presence of trehalose enabled the maintenance of developmental competence (formation of blastocysts) as well as normal gene expression levels of HSP70 and DNMT1 at dehydration levels reaching up to 63% of water loss. CONCLUSION Intracellular trehalose delivery through CRNPs improves dehydration tolerance of COCs, which opens new options for oocyte storage and fertility preservation at ambient temperatures.
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Affiliation(s)
- Pei-Chih Lee
- Smithsonian's National Zoo and Conservation Biology Institute, Washington, D.C., USA
| | - Samantha Stewart
- Fischell Department of Bioengineering, University of Maryland, College Park, MD, USA
| | - Olga Amelkina
- Smithsonian's National Zoo and Conservation Biology Institute, Washington, D.C., USA
| | - Hannah Sylvester
- Smithsonian's National Zoo and Conservation Biology Institute, Washington, D.C., USA
| | - Xiaoming He
- Fischell Department of Bioengineering, University of Maryland, College Park, MD, USA
| | - Pierre Comizzoli
- Smithsonian's National Zoo and Conservation Biology Institute, Washington, D.C., USA.
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Luciano AM, Franciosi F, Dey P, Ladron De Guevara M, Monferini N, Bonumallu SKN, Musmeci G, Fagali Franchi F, Garcia Barros R, Colombo M, Lodde V. Progress toward species-tailored prematuration approaches in carnivores. Theriogenology 2023; 196:202-213. [PMID: 36423514 DOI: 10.1016/j.theriogenology.2022.11.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 11/05/2022] [Accepted: 11/09/2022] [Indexed: 11/13/2022]
Abstract
In the past four decades, the bovine model has been highly informative and inspiring to assisted reproductive technologies (ART) in other species. Most of the recent advances in ART have come from studies in cattle, particularly those unveiling the importance of several processes that must be recapitulated in vitro to ensure the proper development of the oocyte. The maintenance of structural and functional communications between the cumulus cells and the oocyte and a well-orchestrated chromatin remodeling with the gradual silencing of transcriptional activity represent essential processes for the progressive acquisition of oocyte developmental competence. These markers are now considered the milestones of physiological approaches to increase the efficiency of reproductive technologies. Different in vitro approaches have been proposed. In particular, the so-called "pre-IVM" or "prematuration" is a culture step performed before in vitro maturation (IVM) to support the completion of the oocyte differentiation process. Although these attempts only partially improved the embryo quality and yield, they currently represent a proof of principle that oocytes retrieved from an ovary or an ovarian batch shouldn't be treated as a whole and that tailored approaches can be developed for culturing competent oocytes in several species, including humans. An advancement in ART's efficiency would be desirable in carnivores, where the success is still limited. Since the progress in reproductive medicine has often come from comparative studies, this review highlights aspects that have been critical in other species and how they may be extended to carnivores.
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Affiliation(s)
- Alberto Maria Luciano
- Reproductive and Developmental Biology Laboratory, Department of Veterinary Medicine and Animal Sciences, University of Milan, 26900, Lodi, Italy.
| | - Federica Franciosi
- Reproductive and Developmental Biology Laboratory, Department of Veterinary Medicine and Animal Sciences, University of Milan, 26900, Lodi, Italy
| | - Pritha Dey
- Reproductive and Developmental Biology Laboratory, Department of Veterinary Medicine and Animal Sciences, University of Milan, 26900, Lodi, Italy
| | - Magdalena Ladron De Guevara
- Reproductive and Developmental Biology Laboratory, Department of Veterinary Medicine and Animal Sciences, University of Milan, 26900, Lodi, Italy
| | - Noemi Monferini
- Reproductive and Developmental Biology Laboratory, Department of Veterinary Medicine and Animal Sciences, University of Milan, 26900, Lodi, Italy
| | - Sai Kamal Nag Bonumallu
- Reproductive and Developmental Biology Laboratory, Department of Veterinary Medicine and Animal Sciences, University of Milan, 26900, Lodi, Italy
| | - Giulia Musmeci
- Reproductive and Developmental Biology Laboratory, Department of Veterinary Medicine and Animal Sciences, University of Milan, 26900, Lodi, Italy
| | - Fernanda Fagali Franchi
- Reproductive and Developmental Biology Laboratory, Department of Veterinary Medicine and Animal Sciences, University of Milan, 26900, Lodi, Italy
| | - Rodrigo Garcia Barros
- Reproductive and Developmental Biology Laboratory, Department of Veterinary Medicine and Animal Sciences, University of Milan, 26900, Lodi, Italy
| | - Martina Colombo
- Reproductive and Developmental Biology Laboratory, Department of Veterinary Medicine and Animal Sciences, University of Milan, 26900, Lodi, Italy
| | - Valentina Lodde
- Reproductive and Developmental Biology Laboratory, Department of Veterinary Medicine and Animal Sciences, University of Milan, 26900, Lodi, Italy
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Yoshida T, Alam ME, Hanafusa K, Tsujimoto Y, Tsukamoto M, Kanegi R, Inaba T, Sugiura K, Hatoya S. Effects of the preservation medium and storage duration of domestic cat ovaries on the maturational and developmental competence of oocytes in vitro. J Reprod Dev 2022; 68:160-164. [PMID: 35013020 PMCID: PMC8979801 DOI: 10.1262/jrd.2021-084] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We examined the effectiveness of saline, Euro-Collins solution (EC), and ET-Kyoto solution (ET-K) as preservation media for the cold storage of feline ovaries. Ovaries were maintained in these media at 4°C for 24, 48, or 72 h until oocyte retrieval. The ET-K group exhibited a higher oocyte maturation rate than the saline group after 72 h of storage. Moreover, ET-K could sustain the competence of the feline oocytes to cleave after 48 h, and the morula formation rate of the ET-K group was higher than that of the other groups after 24 and 48 h. Furthermore, the ET-K group exhibited a higher blastocyst formation rate than the other groups after storage for 24 h, and only ET-K retained the developmental competence in blastocysts after 48 h of storage. In addition, regarding the cell numbers of the blastocysts, there was no significant difference among the tested groups. In conclusion, our results indicate that ET-K is a suitable preservation medium for feline ovaries.
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Affiliation(s)
- Takumi Yoshida
- Department of Advanced Pathobiology, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Osaka 598-8531, Japan
| | - Md Emtiaj Alam
- Department of Advanced Pathobiology, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Osaka 598-8531, Japan.,Department of Veterinary and Animal Sciences, Faculty of Veterinary and Animal Sciences, Rajshahi University, Rajshahi 6205, Bangladesh
| | - Keisuke Hanafusa
- Department of Advanced Pathobiology, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Osaka 598-8531, Japan
| | - Yasunori Tsujimoto
- Department of Advanced Pathobiology, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Osaka 598-8531, Japan
| | - Masaya Tsukamoto
- Department of Advanced Pathobiology, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Osaka 598-8531, Japan
| | - Ryoji Kanegi
- Department of Advanced Pathobiology, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Osaka 598-8531, Japan
| | - Toshio Inaba
- Department of Advanced Pathobiology, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Osaka 598-8531, Japan
| | - Kikuya Sugiura
- Department of Advanced Pathobiology, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Osaka 598-8531, Japan
| | - Shingo Hatoya
- Department of Advanced Pathobiology, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Osaka 598-8531, Japan
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Arayatham S, Buntasana S, Padungros P, Tharasanit T. Membrane-permeable trehalose improves the freezing ability and developmental competence of in-vitro matured feline oocytes. Theriogenology 2022; 181:16-23. [PMID: 35007820 DOI: 10.1016/j.theriogenology.2022.01.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Revised: 12/17/2021] [Accepted: 01/02/2022] [Indexed: 12/27/2022]
Abstract
Oocytes are highly sensitive to cryopreservation, which frequently results in an irreversible loss of developmental competence. We examined the effect of membrane-permeable trehalose on the freezing ability of feline oocytes matured in vitro. In Experiment 1, intracellular trehalose (trehalose hexaacetate; Tre-(OAc)6) was synthesized from trehalose precursor and subjected to spectroscopic characterization. The membrane permeability of the Tre-(OAc)6 was investigated by incubating oocytes with different concentrations of Tre-(OAc)6 (3, 15, and 30 mM). Optimum concentration and the toxicity of Tre-(OAc)6 were assessed in Experiment 2. The effects of Tre-(OAc)6 on freezing ability in terms of apoptotic gene expression and developmental competence of in-vitro matured oocytes were examined in Experiments 3 and 4, respectively. The Tre-(OAc)6 permeated into the ooplasm of cat oocytes in a dose- and time-dependent manner. The highest concentration of intracellular trehalose was detected when the oocytes were incubated for 24 h with 30 mM Tre-(OAc)6. For the toxicity test, incubation of oocytes with 3 mM Tre-(OAc)6 for 24 h did not affect maturation rate and embryo development. However, high doses of Tre-(OAc)6 (15 and 30 mM) significantly reduced maturation and fertilization rates (p < 0.05). In addition, frozen-thawed oocytes treated with 3 mM Tre-(OAc)6 significantly upregulated anti-apoptotic (BCL-2) gene expression compared with the control (0 mM) and other Tre-(OAc)6 concentrations (15 and 30 mM). Oocyte maturation in the presence of 3 mM Tre-(OAc)6 prior to cryopreservation significantly improved oocyte developmental competence in terms of cleavage and blastocyst rates when compared with the control group (p < 0.05). Our results lead us to infer that increasing the levels of intracellular trehalose by Tre-(OAc)6 during oocyte maturation improves the freezing ability of feline oocytes, albeit at specific concentrations.
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Affiliation(s)
- Saengtawan Arayatham
- Department of Obstetrics, Gynaecology and Reproduction, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, 10330, Thailand
| | - Supanat Buntasana
- Green Chemistry for Fine Chemical Productions STAR, Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok, 10330, Thailand
| | - Panuwat Padungros
- Green Chemistry for Fine Chemical Productions STAR, Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok, 10330, Thailand
| | - Theerawat Tharasanit
- Department of Obstetrics, Gynaecology and Reproduction, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, 10330, Thailand; Veterinary Clinical Stem Cells and Bioengineering Research Unit, Chulalongkorn University, Bangkok, 10330, Thailand.
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6
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Tharasanit T, Thuwanut P. Oocyte Cryopreservation in Domestic Animals and Humans: Principles, Techniques and Updated Outcomes. Animals (Basel) 2021; 11:ani11102949. [PMID: 34679970 PMCID: PMC8533007 DOI: 10.3390/ani11102949] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Revised: 10/05/2021] [Accepted: 10/06/2021] [Indexed: 12/25/2022] Open
Abstract
Oocyte cryopreservation plays important roles in basic research and the application of models for genetic preservation and in clinical situations. This technology provides long-term storage of gametes for genetic banking and subsequent use with other assisted reproductive technologies. Until recently, oocytes have remained the most difficult cell type to freeze, as the oocytes per se are large with limited surface area to cytoplasm ratio. They are also highly sensitive to damage during cryopreservation, and therefore the success rate of oocyte cryopreservation is generally poor when compared to noncryopreserved oocytes. Although advancement in oocyte cryopreservation has progressed rapidly for decades, the improvement of cryosurvival and clinical outcomes is still required. This review focuses on the principles, techniques, outcomes and prospects of oocyte cryopreservation in domestic animals and humans.
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Affiliation(s)
- Theerawat Tharasanit
- Department of Obstetrics, Gynecology and Reproduction, Faculty of Veterinary Science, Bangkok 10330, Thailand
- Veterinary Clinical Stem Cells and Bioengineering Research Unit, Chulalongkorn University, Bangkok 10330, Thailand
- Correspondence:
| | - Paweena Thuwanut
- Department of Obstetrics and Gynecology, Division of Reproductive Medicine, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand;
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Jaworski JP, Urrutia M, Dascal E, Jaita G, Peluffo MC. C-C motif chemokine receptor 2 as a novel intermediate in the ovulatory cascade. Mol Hum Reprod 2021; 26:289-300. [PMID: 32159806 DOI: 10.1093/molehr/gaaa020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2019] [Revised: 02/28/2020] [Indexed: 12/12/2022] Open
Abstract
Expression of immune function genes within follicle cells has been reported in ovaries from many species. Recent work from our laboratory showed a direct effect of the monocyte chemoattractant protein 1/C-C motif chemokine receptor 2 system within the feline cumulus oocyte complex, by increasing the mRNA levels of key genes involved in the ovulatory cascade in vitro. Studies were designed to evaluate if C-C motif chemokine receptor 2 acts as a novel mediator of the ovulatory cascade in vitro. Therefore, feline cumulus oocyte complexes were cultured in the presence or absence of a highly selective C-C motif chemokine receptor 2 antagonist together with known inducers of cumulus-oocyte expansion and/or oocyte maturation to assess mRNA expression of key genes related to periovulatory events in other species as well as oocyte maturation. Also, the effects of recombinant monocyte chemoattractant protein 1 on spontaneous or gonadotrophin-induced oocyte maturation were assessed. This is an in vitro system using isolated cumulus oocyte complexes from feline ovaries. The present study reveals the modulation of several key ovulatory genes by a highly selective C-C motif chemokine receptor 2 antagonist. However, this antagonist was not enough to block the oocyte maturation induced by gonadotropins or amphiregulin. Nonetheless, recombinant monocyte chemoattractant protein 1 had a significant effect on spontaneous oocyte maturation, increasing the percentage of metaphase II stage oocytes in comparison to the control. This is the first study in any species to establish C-C motif chemokine receptor 2 as a mediator of some actions of the mid-cycle gonadotrophin surge.
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Affiliation(s)
- J P Jaworski
- Instituto de Virología, INTA (National Institute of Agricultural Technology-Instituto Nacional de Tecnología Agropecuaria)-CONICET, Argentina. Las Cabañas y Los Reseros s/n, Las Cabañas y Los Reseros 10 s/n, Castelar, Argentina
| | - M Urrutia
- Centro de Investigaciones Endocrinológicas "Dr. César Bergadá" (CEDIE), CONICET - FEI - División de Endocrinología, Hospital de Niños Ricardo Gutiérrez, Gallo 1330, C1425EFD Ciudad Autónoma de Buenos Aires, Argentina
| | - E Dascal
- Centro de Investigaciones Endocrinológicas "Dr. César Bergadá" (CEDIE), CONICET - FEI - División de Endocrinología, Hospital de Niños Ricardo Gutiérrez, Gallo 1330, C1425EFD Ciudad Autónoma de Buenos Aires, Argentina
| | - G Jaita
- Instituto de Investigaciones Biomédicas (INBIOMED), Facultad de Medicina CONICET, Universidad de Buenos Aires, Paraguay 2155, C1121ABG Ciudad Autónoma de Buenos Aires, Argentina.,Departamento de Biología Celular e Histología, Facultad de Medicina, Universidad de Buenos Aires Buenos, Paraguay 2155, C1121ABG Ciudad Autónoma de Buenos Aires, Argentina
| | - M C Peluffo
- Centro de Investigaciones Endocrinológicas "Dr. César Bergadá" (CEDIE), CONICET - FEI - División de Endocrinología, Hospital de Niños Ricardo Gutiérrez, Gallo 1330, C1425EFD Ciudad Autónoma de Buenos Aires, Argentina
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Wang S, Lee PC, Elsayed A, Zhang F, Zhang Y, Comizzoli P, Elliott GD. Preserving the Female Genome in Trehalose Glass at Supra-Zero Temperatures: The Relationship Between Moisture Content and DNA Damage in Feline Germinal Vesicles. Cell Mol Bioeng 2020; 14:101-112. [PMID: 33643469 DOI: 10.1007/s12195-020-00635-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Accepted: 07/02/2020] [Indexed: 01/04/2023] Open
Abstract
Introduction Maintaining a stable dry state is critical for long-term preservation of live biomaterials at suprazero temperatures. The objective of the study was to characterize the effect of moisture content on DNA integrity within the germinal vesicle (GV) of feline oocytes following dehydration and storage at 22-24 °C. Methods Using microwave-assisted drying, conditions that led to a predictable and stable moisture content in trehalose solutions were determined. To explore moisture content stability during storage, trehalose samples were dried for 15 min and stored in glass vials at 11 or 43% RH for 8 weeks. To examine whether this condition allowed proper storage of GVs, permeabilized cat oocytes were incubated in trehalose for 10 min and dried for 15 or 30 min. Oocytes then were rehydrated to assess DNA integrity either directly after drying or after 8 weeks of storage in an 11% RH environment. Raman spectroscopy was used to identify the states of dried samples during storage. Results Moisture content was stable during the storage period. There was no significant difference in DNA integrity between fresh and dried samples without storage. After 8 weeks of storage, DNA integrity was maintained in GVs dried for 30 min. Samples dried for 15 min and stored were compromised, suggesting crystallization of the preservation matrix during storage. Biostabilization was optimal when samples were directly processed to moisture contents consistent with storage in the glassy state. Conclusion Microwave-assisted drying processing and storage conditions were optimized to ensure stable long-term storage of structural and functional properties of genetic resources.
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Affiliation(s)
- Shangping Wang
- Department of Mechanical Engineering and Engineering Sciences, University of North Carolina at Charlotte, 9201 University City Blvd., Charlotte, NC 28223 USA
| | - Pei-Chih Lee
- Smithsonian Conservation Biology Institute, National Zoological Park, Washington, DC USA
| | - Amanda Elsayed
- Department of Mechanical Engineering and Engineering Sciences, University of North Carolina at Charlotte, 9201 University City Blvd., Charlotte, NC 28223 USA
| | - Fan Zhang
- Department of Electrical and Computer Engineering, University of North Carolina at Charlotte, Charlotte, NC USA
| | - Yong Zhang
- Department of Electrical and Computer Engineering, University of North Carolina at Charlotte, Charlotte, NC USA
| | - Pierre Comizzoli
- Smithsonian Conservation Biology Institute, National Zoological Park, Washington, DC USA
| | - Gloria D Elliott
- Department of Mechanical Engineering and Engineering Sciences, University of North Carolina at Charlotte, 9201 University City Blvd., Charlotte, NC 28223 USA
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Nowak A, Kochan J, Świętek E, Kij B, Prochowska S, Witarski W, Bugno-Poniewierska M, Niżański W. Survivability and developmental competences of domestic cat (Felis catus) oocytes after Cryotech method vitrification. Reprod Domest Anim 2020; 55:992-997. [PMID: 32516454 DOI: 10.1111/rda.13741] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Revised: 05/15/2020] [Accepted: 05/26/2020] [Indexed: 11/26/2022]
Abstract
The aim of this study was to evaluate the applicability of the Cryotech technique for the vitrification of domestic cat (Felis catus) oocytes, as a model for other feline species threatened with extinction. This technique, in which oocytes are stored in a minimal volume of medium, is already widely used in human assisted reproductive technology. In the first part of this study, a viability test (EtBr/FDA) was used to evaluate the toxicity of the vitrification media (solutions). After IVM, oocytes were placed in vitrification and warming solutions according to the manufacturer's procedure, with or without exposure to liquid nitrogen. The solutions and the vitrification procedure each caused a reduction in oocyte viability, with survival rates of 71.4% in oocytes exposed to the Cryotech media (without cooling in liquid nitrogen), and 62% in oocytes that were vitrified. In the second part of the experiment, parthenogenetic activation was used to evaluate the developmental potential of oocytes previously vitrified using the Cryotech method. After warming, the oocytes were activated using a combination of 0.7 µM ionomycin in TCM 199 medium (5 min) followed by 2 mM 6-DMAP in TCM 199 supplemented with 10% FBS (3 hr), then cultured and evaluated every 24 hr for parthenogenetic cleavage. In the experimental group, 23/50 (46%) cleaved embryos were obtained. Domestic cat oocytes, vitrified by the Cryotech method, are characterized by high survival rates. However, it is necessary to improve the technique to increase the developmental competence of embryos obtained from vitrified oocytes.
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Affiliation(s)
- Agnieszka Nowak
- Department of Animal Reproduction, Anatomy and Genomics, University of Agriculture in Krakow, Krakow, Poland
| | - Joanna Kochan
- Department of Animal Reproduction, Anatomy and Genomics, University of Agriculture in Krakow, Krakow, Poland
| | - Ewa Świętek
- Department of Animal Reproduction, Anatomy and Genomics, University of Agriculture in Krakow, Krakow, Poland
| | - Barbara Kij
- Department of Animal Reproduction, Anatomy and Genomics, University of Agriculture in Krakow, Krakow, Poland
| | - Sylwia Prochowska
- Department of Reproduction and Clinic of Farm Animals, Wroclaw University of Environmental and Life Sciences, Wrocław, Poland
| | - Wojciech Witarski
- Department of Animal Molecular Biology, National Institute of Animal Production, Krakow, Poland
| | - Monika Bugno-Poniewierska
- Department of Animal Reproduction, Anatomy and Genomics, University of Agriculture in Krakow, Krakow, Poland
| | - Wojciech Niżański
- Department of Reproduction and Clinic of Farm Animals, Wroclaw University of Environmental and Life Sciences, Wrocław, Poland
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10
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Rojo JL, Jaworski JP, Peluffo MC. Direct role of the C-C motif chemokine receptor 2/monocyte chemoattractant protein 1 system in the feline cumulus oocyte complex†. Biol Reprod 2020; 100:1046-1056. [PMID: 30395163 DOI: 10.1093/biolre/ioy237] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Revised: 08/14/2018] [Accepted: 11/01/2018] [Indexed: 01/12/2023] Open
Abstract
Studies were designed to (a) evaluate the mRNA expression of the C-C motif chemokine receptor 2 (CCR2) and its chemokine ligands, as well as genes related to periovulatory events, within the cumulus oocyte complex (COC) and follicle wall after a luteinizing hormone (LH) stimulus in cultured feline antral follicles; (b) assess the immunolocalization of CCR2 and its main ligand (monocyte chemoattractant protein 1, MCP1) within the feline COC; and (c) examine the direct effects of exogenous recombinant MCP1 on mRNA expression of the CCR2 receptor and MCP1 as well as key periovulatory genes in the COC, using a feline COC culture system. Both culture systems were developed by our laboratory and exhibit physiological response to gonadotropin stimuli. In summary, this study demonstrated mRNA expression of CCR2 receptor and its assessed ligands (MCP1, MCP2, MCP3, and MCP4) within the feline COC and follicle antral wall, and a significant increase in CCR2 mRNA by LH within the COC. Also, CCR2 and MCP1 immunoreactivity was observed in the oocyte and cumulus cells of the feline COC. Remarkably, this is the first report, in any species, describing a direct effect of the recombinant MCP1 in the CCR2/MCP1 system within the COC, by increasing the mRNA levels of key genes involved in the ovulatory cascade, as well as its own receptor CCR2. Together, these data suggest that CCR2 receptor signaling in the COC may regulate events critical for promoting cumulus oocyte expansion and/or oocyte maturation.
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Affiliation(s)
- Julieta Laura Rojo
- Centro de Investigaciones Endocrinológicas "Dr César Bergadá", CONICET-FEI-División de Endocrinología, Hospital de Niños Ricardo Gutiérrez, Ciudad Autónoma de Buenos Aires, Argentina
| | - Juan Pablo Jaworski
- National Institute of Agricultural Technology-Instituto Nacional de tecnología agropecuaria-CONICET, Castelar, Argentina
| | - Marina Cinthia Peluffo
- Centro de Investigaciones Endocrinológicas "Dr César Bergadá", CONICET-FEI-División de Endocrinología, Hospital de Niños Ricardo Gutiérrez, Ciudad Autónoma de Buenos Aires, Argentina
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Lee PC, Comizzoli P. Desiccation and supra-zero temperature storage of cat germinal vesicles lead to less structural damage and similar epigenetic alterations compared to cryopreservation. Mol Reprod Dev 2019; 86:1822-1831. [PMID: 31549479 PMCID: PMC7386781 DOI: 10.1002/mrd.23276] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Accepted: 09/04/2019] [Indexed: 02/06/2023]
Abstract
Understanding cellular and molecular damages in oocytes during exposure to extreme conditions is essential to optimize long-term fertility preservation approaches. Using the domestic cat (Felis catus) model, we are developing drying techniques for oocytes' germinal vesicles (GVs) as a more economical alternative to cryopreservation. The objective of the study was to characterize the influence of desiccation on nuclear envelope conformation, chromatin configuration, and the relative fluorescent intensities of histone H3 trimethylation at lysine 4 (H3K4me3) and at lysine 9 (H3K9me3) compared to vitrification. Results showed that higher proportions of dried/rehydrated GVs maintained normal nuclear envelope conformation and chromatin configuration than vitrified/warmed counterparts. Both preservation methods had a similar influence on epigenetic patterns, lowering H3K4me3 intensity to under 40% while maintaining H3K9me3 levels. Further analysis revealed that the decrease of H3K4me3 intensity mainly occurred during microwave dehydration and subsequent rehydration, whereas sample processing (permeabilization and trehalose exposure) or storage did not significantly affect the epigenetic marker. Moreover, rehydration either directly or stepwise with trehalose solutions did not influence the outcome. This is the first report demonstrating that the incidence of GV damages is lower after desiccation/rehydration than vitrification/warming.
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Affiliation(s)
- Pei-Chih Lee
- Smithsonian Conservation Biology Institute, National Zoological Park, Washington, D.C., Columbia
| | - Pierre Comizzoli
- Smithsonian Conservation Biology Institute, National Zoological Park, Washington, D.C., Columbia
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Lee PC, Wildt DE, Comizzoli P. Proteomic analysis of germinal vesicles in the domestic cat model reveals candidate nuclear proteins involved in oocyte competence acquisition. Mol Hum Reprod 2019; 24:14-26. [PMID: 29126204 DOI: 10.1093/molehr/gax059] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Accepted: 11/04/2017] [Indexed: 12/14/2022] Open
Abstract
STUDY QUESTION Do nuclear proteins in the germinal vesicle (GV) contribute to oocyte competence acquisition during folliculogenesis? SUMMARY ANSWER Proteomic analysis of GVs identified candidate proteins for oocyte competence acquisition, including a key RNA processing protein-heterogeneous nuclear ribonucleoprotein A2/B1 (hnRNPA2B1). WHAT IS KNOWN ALREADY The domestic cat GV, which is physiologically similar to the human GV, gains the intrinsic ability to resume meiosis and support early embryo development during the pre-antral-to-antral follicle transition. However, little is known about nuclear proteins that contribute to this developmental process. STUDY DESIGN SIZE, DURATION GVs were enriched from pre-antral (incompetent) and antral (competent) follicles from 802 cat ovaries. Protein lysates were subjected to quantitative proteomic analysis to identify differentially expressed proteins in GVs from the two follicular categories. PARTICIPANTS/MATERIALS, SETTING, METHODS Two biological replicates (from independent pools of ovaries) of pre-antral versus antral samples were labeled by tandem mass tags and then assessed by liquid chromatography-tandem mass spectrometry. Proteomic data were analyzed according to gene ontology and a protein-protein interaction network. Immunofluorescent staining and protein inhibition assays were used for validation. MAIN RESULTS AND THE ROLE OF CHANCE A total of 174 nuclear proteins was identified, with 54 being up-regulated and 22 down-regulated (≥1.5-fold) after antrum formation. Functional protein analysis through gene ontology over-representation tests revealed that changes in molecular network within the GVs during this transitional phase were related to chromatin reorganization, gene transcription, and maternal RNA processing and storage. Protein inhibition assays verified that hnRNPA2B1, a key nuclear protein identified, was required for oocyte meiotic maturation and subsequent blastocyst formation. LARGE SCALE DATA Data are available via ProteomeXchange with identifier PXD007211. LIMITATIONS REASONS FOR CAUTION Proteins identified by proteomic comparison may (i) be involved in processes other than competence acquisition during the pre-antral-to-antral transition or (ii) be co-expressed in other macrostructures besides the GV. Expressional and functional validations should be performed for candidate proteins before downstream application. WIDER IMPLICATIONS OF THE FINDINGS Collective results generated a blueprint to better understand the molecular mechanisms involved in GV competence acquisition and identified potential nuclear competence markers for human fertility preservation. STUDY FUNDING AND COMPETING INTEREST(S) Funded by the National Center for Research Resources (R01 RR026064), a component of the National Institutes of Health (NIH) and currently by the Office of Research Infrastructure Programs/Office of the Director (R01 OD010948). The authors declare that there is no conflict of interest.
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Affiliation(s)
- P-C Lee
- Center for Species Survival, Smithsonian Conservation Biology Institute, National Zoological Park, Washington, DC 20008, USA
| | - D E Wildt
- Center for Species Survival, Smithsonian Conservation Biology Institute, National Zoological Park, Washington, DC 20008, USA
| | - P Comizzoli
- Center for Species Survival, Smithsonian Conservation Biology Institute, National Zoological Park, Washington, DC 20008, USA
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Picton HM. Preservation of female fertility in humans and animal species. Anim Reprod 2018; 15:301-309. [PMID: 34178153 PMCID: PMC8202459 DOI: 10.21451/1984-3143-ar2018-0089] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Accepted: 07/06/2018] [Indexed: 12/03/2022] Open
Abstract
A detailed understanding of the cryobiology of gametes and complex tissues has led to the development of methods that facilitate the successful low temperature banking of isolated mature human oocytes, or immature oocytes in situ within fragments of human ovarian cortex. Although many outstanding research challenges remain to be addressed, the successful development of new treatments to preserve female fertility for a range of clinical indications has largely been underpinned by the conduct of extensive, fundamental research on oocytes and ovarian tissues from a number of laboratory and commercially important farm species. Indeed, the most recent evidence from large animals suggests that it is also possible to cryopreserve intact whole ovaries along with their supporting vasculature for later auto-transplantation and restoration of natural fertility. This review will explore how the methods developed to preserve human oocytes and ovarian tissues can now be used strategically to support the development of conservation strategies aimed at safeguarding the genetic diversity of commercially important domestic animals and also of preserving the female germplasm for wild animals and endangered species.
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Affiliation(s)
- Helen Mary Picton
- Reproduction and Early Development Research Group, Discovery and Translational Science Department, Leeds Institute Of Cardiovascular and Metabolic Medicine, School of Medicine, University of Leeds, UK
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Rojo JL, Linari M, Young KA, Peluffo MC. Stromal-derived factor 1 directly promotes genes expressed within the ovulatory cascade in feline cumulus oocyte complexes. J Assist Reprod Genet 2018; 35:785-792. [PMID: 29516335 PMCID: PMC5984889 DOI: 10.1007/s10815-018-1150-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Accepted: 02/26/2018] [Indexed: 01/02/2023] Open
Abstract
PURPOSE We hypothesized that the chemokine SDF1/CXCR4 system was present in feline cumulus-oocyte complexes (COCs) and that COCs cultured with SDF1 would directly upregulate gene expression in the ovulatory cascade. METHODS Ovaries (n = 50) were obtained from adult domestic cats during the breeding season and COCs were recovered from antral follicles. Because IVM media triggers cumulus-oocyte expansion, culture conditions needed to be optimized to study periovulatory genes. After optimization, the effects of 25 ng/ml SDF1 and the CXCR4 inhibitor were examined in a COC culture for 3, 12, and 24 h. RESULTS MEM-hepes with 1% of charcoal stripped-FBS was the optimized culture medium, assessed by the expansion of COCs at 24 h in the gonadotropin (GNT) group but not in the media with serum alone. The mRNA expression of HAS2, TNFAIP6, PTX3, and AREG peaked at 3 h in GNT group as compared to all other groups (p < 0.05). COCs cultured with SDF1 showed increased HAS2 and TNFAIP6 mRNA expression at 3 h compared to negative controls and to the CXCR4 inhibitor group. CXCR4 and SDF1 immunostaining was present in both cumulus cells and the oocyte. CONCLUSIONS These results demonstrate that GNT stimulation upregulates key periovulatory genes and expansion in feline COCs from antral follicles, and support the use of this culture system to examine molecular processes within the COC. In addition, SDF1 directly promotes key periovulatory genes in feline COCs, suggesting that the SDF1-CXCR4 pathway may extend its function beyond a chemoattractant, and may play a direct role within the COC.
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Affiliation(s)
- Julieta L Rojo
- Centro de Investigaciones Endocrinológicas "Dr. César Bergadá" (CEDIE), CONICET, FEI, División de Endocrinología Hospital de Niños Ricardo Gutiérrez, Gallo 1330, CABA, C1425EFD, Buenos Aires, Argentina
| | - Martina Linari
- Centro de Investigaciones Endocrinológicas "Dr. César Bergadá" (CEDIE), CONICET, FEI, División de Endocrinología Hospital de Niños Ricardo Gutiérrez, Gallo 1330, CABA, C1425EFD, Buenos Aires, Argentina
| | - Kelly A Young
- Department of Biological Sciences, California State University Long Beach, Long Beach, CA, 90840, USA
| | - Marina C Peluffo
- Centro de Investigaciones Endocrinológicas "Dr. César Bergadá" (CEDIE), CONICET, FEI, División de Endocrinología Hospital de Niños Ricardo Gutiérrez, Gallo 1330, CABA, C1425EFD, Buenos Aires, Argentina.
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Cao X, Li J, Xue H, Wang S, Zhao W, Du Z, Yang Y, Yue Z. Effect of vitrification on meiotic maturation, mitochondrial distribution and glutathione synthesis in immature silver fox cumulus oocyte complexes. Theriogenology 2017; 91:104-111. [DOI: 10.1016/j.theriogenology.2016.12.037] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Revised: 12/22/2016] [Accepted: 12/29/2016] [Indexed: 10/20/2022]
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Phillips TC, Wildt DE, Comizzoli P. Incidence of methylated histones H3K4 and H3K79 in cat germinal vesicles is regulated by specific nuclear factors at the acquisition of developmental competence during the folliculogenesis. J Assist Reprod Genet 2016; 33:783-94. [PMID: 27059775 PMCID: PMC4889483 DOI: 10.1007/s10815-016-0706-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2015] [Accepted: 03/21/2016] [Indexed: 11/26/2022] Open
Abstract
PURPOSE This study aims to characterize the regulations of histone methylations, key epigenetic markers of oocyte competence, in germinal vesicle (GV) from different follicles (preantral, early, small, or large antral stage) using the domestic cat model. METHODS In Experiment 1, the incidence of H3K4me3 or H3K79me2 was determined in GVs from the diverse follicle stages directly or after exposure to (1) a methyltransferase inhibitor, (2) sonication to fracture the cytoplasmic membranes and wash away the cytoplasmic content, or (3) methyltransferase inhibitor followed by sonication. In Experiment 2, the presence and maintenance of nuclear methyltransferases SMYD3 and DOT1L (regulating H3K4me3 and H3K79me2, respectively) was characterized in separate GV stages before and after sonication. Functionality of GVs from the various follicle stages (with or without transient isolation from the cytoplasm) then was assessed in Experiment 3 by transfer into recipient competent oocytes. RESULTS The incidence of histones H3K4me3 and H3K79me2 within the GV were influenced by the cytoplasmic environment at all stages except at the transition to the early antral stage where nuclear regulating factors appeared to be mainly involved. The methyltransferase SMYD3 and DOT1L also appeared tightly bound to the nucleus at that transition. Interestingly, oocytes reconstructed with a GV isolated from the cytoplasm for a prolonged period had the capacity to form an embryo after fertilization which proved that communication between the donor GV and the host cytoplasm (likely including the regulation of epigenetic factors) could be restored. CONCLUSIONS Histone methylation apparently becomes regulated by specific nuclear factors at the acquisition of competence during the folliculogenesis and does not seem to be disrupted by prolonged isolation from the surrounding cytoplasm.
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Affiliation(s)
- Tameka C Phillips
- Smithsonian Conservation Biology Institute, National Zoological Park, Washington, DC, 20008, USA
- Smithsonian Conservation Biology Institute, National Zoological Park, Front Royal, VA, 22630, USA
| | - David E Wildt
- Smithsonian Conservation Biology Institute, National Zoological Park, Washington, DC, 20008, USA
- Smithsonian Conservation Biology Institute, National Zoological Park, Front Royal, VA, 22630, USA
| | - Pierre Comizzoli
- Smithsonian Conservation Biology Institute, National Zoological Park, Washington, DC, 20008, USA.
- Smithsonian Conservation Biology Institute, National Zoological Park, Front Royal, VA, 22630, USA.
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Felis catus ovary as a model to study follicle biology in vitro. J Assist Reprod Genet 2015; 32:1105-11. [PMID: 26089083 DOI: 10.1007/s10815-015-0511-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Accepted: 06/04/2015] [Indexed: 12/13/2022] Open
Abstract
PURPOSE The current study was designed to evaluate the response of individual intact antral follicles from adult female domestic cats to a luteinizing hormone (LH) stimulus in vitro by assessing cumulus-oocyte expansion (C-OE) and steroid production. METHODS C-OE and steroid levels (estradiol [E2] and progesterone [P4]) obtained from individual antral feline follicles (n = 366 follicles; n = 56 cats) were analyzed after 12 or 24 h of culture in the presence or absence of LH (low [3.4 ng/ml] or high [100 ng/ml]). RESULTS At the end of the culture, the highest percentage of expanded cumulus-oocyte complexes (COCs) was observed in the LH groups at 12 or 24 h in comparison to their controls (p < 0.001). There was a significant increase in expanded COCs when comparing LH concentrations (high vs. low) at 12 or 24 h. Higher levels of both E2 and P4 were observed in the media from antral follicles after 12 and 24 h of culture in the presence of LH (both concentration, p < 0.05). There was no association between hormone levels and follicle diameter; high variability was observed in the steroid levels produced by antral follicles within all treatment groups. CONCLUSIONS These data indicate, for the first time, that feline antral follicles (0.5-2 mm) from different stages of the natural estrous cycle can be cultured and will respond to an LH stimulus, based on an increase in steroid levels as well as C-OE after 12 or 24 h in culture.
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Elliott GD, Lee PC, Paramore E, Van Vorst M, Comizzoli P. Resilience of oocyte germinal vesicles to microwave-assisted drying in the domestic cat model. Biopreserv Biobank 2015; 13:164-71. [PMID: 26035005 PMCID: PMC4559202 DOI: 10.1089/bio.2014.0078] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The ability to compact and inject the cat germinal vesicle (GV) into a recipient cytoplast allows exploration of a new fertility preservation strategy that avoids whole oocyte freezing. The objective of the present study was to understand the impact of water loss and storage time on GV DNA integrity. Immature cat oocytes were exposed to 1.5 M trehalose for 10 min before microwave-assisted dehydration for 0, 5, 10, 15, 20, 25, 30, or 40 min. Oocytes then were rehydrated to assess chromatin configuration and the incidence of DNA fragmentation (TUNEL assay). The moisture content progressively decreased (p<0.05) from 1.7 to 0.1 gH2O/gDW over the first 30 min, but did not decrease further (p>0.05) after 40 min. Chromatin configuration was unaffected (p>0.05) over time. The percentage of GVs with DNA fragmentation was unaltered (p>0.05) from 0 to 30 min of treatment (range, 6.1%-12%), but increased (p<0.05) to 32.5% after 40 min. Next, the influence of storage at two different supra-zero temperatures after 30 min of drying was investigated. Oocyte-loaded, microwave-treated filters were individually sealed in Dri-Shield moisture barrier bags and stored at 4°C or ambient temperature for 0 to 8 weeks. Moisture contents gradually decreased (p<0.05) from 0.12 to 0.10 gH2O/gDW after 8 weeks of storage at 4°C or ambient temperature. The percentage of GVs with DNA fragmentation more than doubled (p<0.05) from 0 (14.3%) to 2 days (30.0%-33.0%), but remained stable (p>0.05) thereafter (1 through 4 weeks, 25.0%-35.0%). Collective results demonstrate the feasibility of using microwave processing to dehydrate the mammalian GV to a moisture content that is nonlethal and enables nonfrozen storage, an alternative approach for preserving the maternal genome at cool or ambient temperature.
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Affiliation(s)
- Gloria D Elliott
- 1Department of Mechanical Engineering and Engineering Sciences, University of North Carolina at Charlotte, Charlotte, North Carolina
| | - Pei-Chih Lee
- 2Smithsonian Conservation Biology Institute, National Zoological Park, Washington, District of Columbia
| | - Elisha Paramore
- 1Department of Mechanical Engineering and Engineering Sciences, University of North Carolina at Charlotte, Charlotte, North Carolina
| | - Matthew Van Vorst
- 1Department of Mechanical Engineering and Engineering Sciences, University of North Carolina at Charlotte, Charlotte, North Carolina
| | - Pierre Comizzoli
- 2Smithsonian Conservation Biology Institute, National Zoological Park, Washington, District of Columbia
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Comizzoli P, Wildt DE. Mammalian fertility preservation through cryobiology: value of classical comparative studies and the need for new preservation options. Reprod Fertil Dev 2014; 26:91-8. [PMID: 24305181 DOI: 10.1071/rd13259] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Human-related fertility preservation strategies have enormous potential for helping sustain and protect other species, especially to assist managing or 'rescuing' the genomes of genetically valuable individuals, including endangered species. However, wider-scale applications are limited by significant physiological variations among species, as well as a lack of fundamental knowledge of basic reproductive traits and cryosensitivity. Systematic and comparative cryopreservation studies (e.g. on membrane biophysical properties and resilience to freezing temperatures) are required to successfully recover gametes and gonadal tissues after thawing and eventually produce healthy offspring. Such data are currently available for humans and a few laboratory and livestock animals, with virtually all other species, including wildlife, having gone unstudied. Interestingly, there also are commonalities among taxa that allow a protocol developed for one species to provide useful information or guidance for another. However, when a rare animal unexpectedly dies there is no time for a prospective understanding of that species' biophysical traits. Because the odds of success will be much lower in such instances, it is essential that more fundamental studies be directed at more species. But also worthwhile is thinking beyond these systematic characterisations to consider the potential of a 'universal preservation protocol' for animal biomaterials.
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Affiliation(s)
- Pierre Comizzoli
- Smithsonian Conservation Biology Institute, National Zoological Park, PO Box 37012 MRC 5502, Washington, DC 20013, USA
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Recent advances and prospects in germplasm preservation of rare and endangered species. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2014; 753:331-56. [PMID: 25091916 DOI: 10.1007/978-1-4939-0820-2_14] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Fertility preservation strategies using cryopreservation have enormous potential for helping sustain and protect rare and endangered species, especially to assist managing or 'rescuing' the genomes of genetically valuable individuals. However, wide-scale applications are still limited by significant physiological variations among species and a sheer lack of fundamental knowledge about basic reproductive traits as well as in germplasm cryobiology. Cryo-studies have been conducted in more species (mainly vertebrates) in the recent years but a vast majority still remains un-studied. Semen cryopreservation represents the most extensive effort with live births reported in more and more species after artificial insemination. Oocyte freezing remains challenging and unsuccessful in wild species and will require more research before becoming a standard procedure. As an alternative to fully grown gametes, gonadal tissue preservation has become a promising option in vertebrates. Yet, more fertility preservation options are necessary to save species so a change in strategy might be required. It is worthwhile thinking beyond systematic characterizations and considering the application of cutting edge approaches to universally preserve the fertility of a vast array of species.
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Luvoni GC. Cryosurvival of ex situ and in situ feline oocytes. Reprod Domest Anim 2013; 47 Suppl 6:266-8. [PMID: 23279515 DOI: 10.1111/rda.12040] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2012] [Accepted: 07/10/2012] [Indexed: 11/28/2022]
Abstract
Cryosurvival of feline oocytes preserved as isolated cells (ex situ) or enclosed in ovarian follicles (in situ) has been demonstrated, and significant advances have recently been achieved. However, an ideal protocol for oocyte cryopreservation has not been established to date because of extreme sensitivity of the structural complex to chilling injury. Several factors, such as stage of maturation, membrane permeability and plasticity of the cytoskeleton, affect cryosurvival of the oocyte. Also, intercellular communications between cumulus cells and oocyte are compromised after freezing or vitrification of ex situ or in situ cumulus-oocyte complexes, which has a detrimental effect on oocyte maturational competence. Despite these issues, embryo development, pregnancies and live kittens have been obtained after in vitro fertilization (by ICSI) and transfer of embryos derived from cryopreserved oocytes. It is a general belief that the efficiency of cryopreservation would increase through a better understanding of oocyte responses to cryoprotectants, cooling rates and all the physical events occurring during the exposure of feline oocytes to low temperatures. Cryobanking of feline oocytes would significantly contribute to the preservation of rare genotypes and to the maintenance of a valuable source of genetic material for research applications.
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Affiliation(s)
- G C Luvoni
- Dipartimento di Scienze Veterinarie per la Salute, la Produzione Animale, e la Sicurezza Alimentare, Università degli Studi di Milano, Milano, Italy.
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Comparative cryobiological traits and requirements for gametes and gonadal tissues collected from wildlife species. Theriogenology 2012; 78:1666-81. [PMID: 22704386 DOI: 10.1016/j.theriogenology.2012.04.008] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2012] [Revised: 04/03/2012] [Accepted: 04/06/2012] [Indexed: 01/16/2023]
Abstract
A major challenge to retaining viability of frozen gametes and reproductive tissues is to understand and overcome species-specificities, especially because there is substantial diversity in cryobiological properties and requirements among cell types and tissues. Systematic studies can lead to successful post-thaw recovery, especially after determining: 1) membrane permeability to water and cryoprotectant, 2) cryoprotectant toxicity, 3) tolerance to osmotic changes, and 4) resistance to cooling and freezing temperatures. Although species-dependency ultimately dictates the ability of specific cells and tissues to survive freeze-thawing, there are commonalities between taxa that allow a protocol developed for one species to be useful information for another. This is the reason for performing comparative cryopreservation studies among diverse species. Our laboratory has compared cellular cryotolerance, especially in spermatozoa, in a diverse group of animals-from corals to elephants-for more than 30 yrs. Characterizing the biophysical traits of gametes and tissues is the most efficient way to develop successful storage and recovery protocols, but, such data are only available for a few laboratory, livestock, and fish species, with virtually all others (wild mammals, birds, reptiles, and amphibians) having gone unstudied. Nonetheless, when a rare animal unexpectedly dies, there is no time to understand the fundamentals of biophysics. In these emergencies, it is necessary to rely on experience and the best data from taxonomically-related species. Fortunately, there are some general similarities among most species, which, for example, allow adequate post-thaw viability. Regardless, there is a priority for more information on biophysical traits and freezing tolerance of distinctive biomaterials, especially for oocytes and gonadal tissues, and even for common, domesticated animals. Our colleague, Dr John Critser was a pioneer in cryobiology, earning that moniker because of his advocacy and devotion to understanding the differences (and similarities) among species to better store living genetic material.
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Alves AE, Kozel AC, Luvoni GC. Vitrification with DAP 213 and Cryotop ofEx SituandIn SituFeline Cumulus-Oocyte Complexes. Reprod Domest Anim 2012; 47:1003-8. [DOI: 10.1111/j.1439-0531.2012.02006.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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In vivo survival of domestic cat oocytes after vitrification, intracytoplasmic sperm injection and embryo transfer. Theriogenology 2012; 77:531-8. [DOI: 10.1016/j.theriogenology.2011.08.028] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2011] [Revised: 07/18/2011] [Accepted: 08/19/2011] [Indexed: 11/19/2022]
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Combelles CMH, Ceyhan ST, Wang H, Racowsky C. Maturation outcomes are improved following Cryoleaf vitrification of immature human oocytes when compared to choline-based slow-freezing. J Assist Reprod Genet 2011; 28:1183-92. [PMID: 22089264 DOI: 10.1007/s10815-011-9674-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2011] [Accepted: 11/02/2011] [Indexed: 10/15/2022] Open
Abstract
PURPOSE The cryopreservation of immature oocytes permits oocyte banking for patients at risk of losing their fertility. However, the optimum protocol for such fertility preservation remains uncertain. METHODS The present study investigated the survival, maturation, cytoskeletal and chromosome organization of sibling immature oocytes leftover from controlled ovarian stimulation cycles, that were either slow-frozen (with choline-substitution) or vitrified. A comparison group included oocytes that were never cryopreserved. RESULTS Among the three groups, comparable rates were observed for both survival (67-70%) and polar body extrusion (59-79%). Significantly more oocytes underwent spontaneous activation after IVM following slow-freezing compared with either vitrification or no cryopreservation. Likewise, the incidence of spindle abnormalities was greatest in the slow-frozen group, with no differences in spindle morphometrics or chromosome organization. CONCLUSIONS While the overall incidence of mature oocytes with normal bipolar spindles from warmed immature oocytes was low, the yield using Cryoleaf vitrification was slightly superior to choline-based slow-freezing.
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Tharasanit T, Manee-In S, Buarpung S, Chatdarong K, Lohachit C, Techakumphu M. Successful pregnancy following transfer of feline embryos derived from vitrified immature cat oocytes using ‘stepwise’ cryoprotectant exposure technique. Theriogenology 2011; 76:1442-9. [DOI: 10.1016/j.theriogenology.2011.06.014] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2011] [Revised: 06/09/2011] [Accepted: 06/13/2011] [Indexed: 10/17/2022]
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Comizzoli P, Pukazhenthi BS, Wildt DE. The competence of germinal vesicle oocytes is unrelated to nuclear chromatin configuration and strictly depends on cytoplasmic quantity and quality in the cat model. Hum Reprod 2011; 26:2165-77. [PMID: 21665874 DOI: 10.1093/humrep/der176] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Chromatin configuration of the germinal vesicle (GV) and quality of the cytoplasm are critical factors in achieving oocyte meiotic and developmental capacity during folliculogenesis. Besides gaining new insights into the timing and cellular mechanisms associated with the acquisition and regulation of GV oocyte competence, the domestic cat model was used to examine (i) the relation between GV chromatin configuration and oocyte functionality during folliculogenesis and (ii) the role of the cytoplasmic environment on the GV competence and stability. METHODS Structural and functional properties of GV oocytes were characterized after isolation from different follicle stages of non-stimulated cat ovaries. GV transfers, artificial chromatin compaction and oocyte vitrification were used to demonstrate the respective roles of GV and cytoplasm on the oocyte functionality. RESULTS GVs acquired the intrinsic capability to resume meiosis during the pre-antral follicle stage, whereas the capacity to support embryo development occurred while the antrum started to form. Chromatin configuration of the GV did not undergo extensive modification during the acquisition of competence or during the arrest of transcriptional activity at the large antral follicle stage. However, the quality and quantity of the cytoplasm regulated and enhanced GV functionality. This finding also held for GVs transferred from incompetent or subpar oocytes into the cytoplasm of good quality oocytes or when chromatin was artificially modified or vitrified. CONCLUSIONS The cat model provides a new insight into GV oocyte structure and function during folliculogenesis while challenging current concepts about oocyte quality criteria based on the GV morphology. This suggests alternative evaluative approaches for oocytes from other species too, including humans. Cat GVs also appear competent at an early follicle stage and are resilient to perturbations which designate this organelle as an attractive target for developing novel fertility preservation tactics.
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Affiliation(s)
- P Comizzoli
- Center for Species Survival, Smithsonian Conservation Biology Institute, Washington, DC 20008, USA.
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Czarny N, Rodger J. Vitrification as a method for genome resource banking oocytes from the endangered Tasmanian devil (Sarcophilus harrisii). Cryobiology 2010; 60:322-5. [DOI: 10.1016/j.cryobiol.2010.02.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2009] [Revised: 02/19/2010] [Accepted: 02/23/2010] [Indexed: 11/30/2022]
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Wildt DE, Comizzoli P, Pukazhenthi B, Songsasen N. Lessons from biodiversity--the value of nontraditional species to advance reproductive science, conservation, and human health. Mol Reprod Dev 2010; 77:397-409. [PMID: 19967718 PMCID: PMC3929270 DOI: 10.1002/mrd.21137] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Reproduction is quintessential to species survival. But what is underappreciated for this discipline is the wondrous array of reproductive mechanisms among species- variations as diverse as the morphology of the species themselves (more than 55,000 vertebrate and 1.1 million invertebrate types). We have investigated only a tiny fraction of these species in reproductive science. Besides the need to fill enormous gaps in a scholarly database, this knowledge has value for recovering and genetically managing rare species as well as addressing certain reproductive issues in humans. This article provides examples, first to advise against oversimplifying reproduction and then to show how such knowledge can have practical use for managing whole animals, populations, or even saving an entire species. We also address the expected challenges and opportunities that could lead to creative shifts in philosophy and effective actions to benefit more species as well as a future generation of reproductive scientists.
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Affiliation(s)
- David E Wildt
- Department of Reproductive Sciences, Center for Species Survival, Smithsonian's National Zoological Park, Conservation & Research Center, Front Royal, Virginia 22630, USA.
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Comizzoli P, Songsasen N, Wildt DE. Protecting and extending fertility for females of wild and endangered mammals. Cancer Treat Res 2010; 156:87-100. [PMID: 20811827 PMCID: PMC3086462 DOI: 10.1007/978-1-4419-6518-9_7] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Pierre Comizzoli
- Department of Reproductive Sciences, Center for Species Survival, Veterinary Hospital, Smithsonian Conservation Biology Institute, Washington, DC, USA.
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Luciano AM, Chigioni S, Lodde V, Franciosi F, Luvoni GC, Modina SC. Effect of different cryopreservation protocols on cytoskeleton and gap junction mediated communication integrity in feline germinal vesicle stage oocytes. Cryobiology 2009; 59:90-5. [DOI: 10.1016/j.cryobiol.2009.05.002] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2008] [Revised: 05/06/2009] [Accepted: 05/07/2009] [Indexed: 11/30/2022]
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Comizzoli P, Wildt DE, Pukazhenthi BS. In VitroCompaction of Germinal Vesicle Chromatin is Beneficial to Survival of Vitrified Cat Oocytes. Reprod Domest Anim 2009; 44 Suppl 2:269-74. [DOI: 10.1111/j.1439-0531.2009.01372.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Czarny NA, Harris MS, Rodger JC. Dissociation and preservation of preantral follicles and immature oocytes from female dasyurid marsupials. Reprod Fertil Dev 2009; 21:640-8. [DOI: 10.1071/rd08303] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2008] [Accepted: 03/05/2009] [Indexed: 11/23/2022] Open
Abstract
The mammalian ovary contains numerous immature preantral follicles that are not dependent on endocrine support, unlike the more mature hormone-dependant antral follicles. Preantral follicles can be enzymatically dissociated to yield immature oocytes that survive sub-zero preservation better as they lack a temperature-sensitive meiotic spindle. These techniques are highly applicable to gamete banking, which is an urgent requirement for Australian carnivorous marsupials as several species have rapidly declining populations and risk extinction. The present study developed protocols for the transport, dissociation, preservation and culture of granulosa cell-oocyte complexes (GOC) from the ovaries of dasyurid marsupials. High viability of GOC following enzymatic dissociation is reported and it was demonstrated that GOC are of significantly better quality following refrigerated storage for 24 h compared with storage at room temperature. Oocytes from primary follicles were not damaged by cold shock or the toxicity of vitrification media and following vitrification in liquid nitrogen 69.42 ± 2.44% of oocytes were viable. However, the surrounding granulosa cells demonstrated significant damage post-thaw. These granulosa cells proliferated during a 48-h culture period resulting in significant improvements in GOC quality. The present study is a valuable step towards cryostorage of dasyurid gametes and represents fundamentally important methods by which we can contribute to the conservation of Australia’s native predators.
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Mahmoud KG, Scholkamy TH, Ahmed YF, Seidel Jr GE, Nawito MF. Effect of Different Combinations of Cryoprotectants onIn VitroMaturation of Immature Buffalo (Bubalus bubalis) Oocytes Vitrified by Straw and Open-Pulled Straw Methods. Reprod Domest Anim 2008; 45:565-71. [DOI: 10.1111/j.1439-0531.2008.01293.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Luciano AM, Franciosi F, Lodde V, Perazzoli F, Slezáková M, Modina S. Cryopreservation of immature bovine oocytes to reconstruct artificial gametes by germinal vesicle transplantation. Reprod Domest Anim 2008; 44:480-8. [PMID: 18992089 DOI: 10.1111/j.1439-0531.2008.01194.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Joining immature gamete cryopreservation and germinal vesicle transplantation (GVT) technique could greatly improve assisted reproductive technologies in animal breeding and human medicine. The present work was aimed to assess the most suitable cryopreservation protocol between slow freezing and vitrification for immature denuded bovine oocytes, able to preserve both nuclear and cytoplasmic competence after thawing. In addition, the outcome of germinal vesicle transfer procedure and gamete reconstruction was tested on the most effective cryopreservation system. Oocytes, isolated from slaughterhouse ovaries, were stored after cumulus cells removal either by slow freezing or by vitrification in open pulled straws. After thawing, oocytes were matured for 24 h in co-culture with an equal number of just isolated intact cumulus enclosed oocytes, and fixed in order to evaluate the stage of meiotic progression and cytoskeleton organization. Our results showed that after warming, vitrified oocytes reached metaphase II (MII) in a percentage significantly higher than oocytes cryopreserved by slow freezing (76.2% and 36.5% respectively, p < 0.05). Moreover, vitrification process preserved the organization of cytoskeleton elements in a higher proportion of oocytes than slow freezing procedure. Therefore vitrification has been identified as the elective method for denuded immature oocytes banking and it has been applied in the second part of the study. Our results showed that 38.3% of oocytes reconstructed from vitrified gametes reached the MII of meiotic division, with efficiency not different from oocytes reconstructed with fresh gametes. We conclude that vitrification represents a suitable method of GV stage denuded oocyte banking since both nuclear and cytoplasmic components derived from cryopreserved immature oocytes can be utilized for GVT.
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Affiliation(s)
- A M Luciano
- Division of Veterinary Anatomy and Histology, Department of Animal Sciences, Faculty of Veterinary Medicine, University of Milan, Via Celoria 10, Milan, Italy.
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Paracrine factors from cumulus-enclosed oocytes ensure the successful maturation and fertilization in vitro of denuded oocytes in the cat model. Fertil Steril 2008; 91:2051-60. [PMID: 18692794 DOI: 10.1016/j.fertnstert.2008.05.069] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2008] [Revised: 05/13/2008] [Accepted: 05/16/2008] [Indexed: 11/23/2022]
Abstract
OBJECTIVE To better characterize cumulus-oocyte interactions during oocyte maturation and fertilization in the cat model. DESIGN Experimental in vitro study. SETTING Smithsonian Institution. ANIMAL(S) Domestic shorthair cats. INTERVENTION(S) Groups of denuded oocytes (DOs) and cumulus-oocyte complexes (COCs) were subjected to in vitro maturation (with or without FSH and LH, with or without the gap junction disruptor 1-heptanol, in separated groups or in coculture) and inseminated in vitro (IVF; in separated groups or in coculture). MAIN OUTCOME MEASURE(S) Nuclear maturation, pronuclear formation, kinetics of early embryo cleavage, and blastocyst formation and quality after different in vitro conditions were compared between DOs cultured separately and DOs cocultured with COCs. RESULT(S) Without FSH and LH, the removal of cumulus cells prevented spontaneous meiotic resumption in DOs. With FSH and LH, groups of DOs progressed to the metaphase I stage but fully advanced to metaphase II only in coculture with intact (nondisrupted) COCs. Groups of DOs cultured separately were fertilized poorly and exhibited no blastocyst formation. In contrast, DOs cocultured with intact COCs during in vitro maturation and IVF recovered fertilizability, and approximately 35% formed blastocysts. CONCLUSION(S) Paracrine factors produced by cumulus-enclosed oocytes in the cat model will help to develop synthetic media for successful in vitro culture of DOs.
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