Biphasic CAPA-IVM Improves Equine Oocyte Quality and Subsequent Embryo Development Without Inducing Genetic Aberrations.
- Journal Article
Summary
This research evaluates the impact of a specific in-vitro maturation method, known as CAPA-IVM, on the quality and developmental competence of horse oocytes. The study reveals that this method improves oocyte quality and developmental potential without causing genetic abnormalities.
Research Background
In the world of assisted reproduction, in-vitro maturation (IVM) of oocytes is commonly used, especially in cases where prior hormonal stimulation is not advisable. The key challenge with this is that oocytes matured in a laboratory setting often don’t reach the level of developmental competence of those matured in a host organism. This research evaluates a particular IVM method known as Capacitation IVM (CAPA-IVM), which includes an additional pre-maturation step. The purpose of this step is to better synchronize the oocyte’s cytoplasmic and nuclear maturity by extending the time for cytoplasm to accrue essential components.
- The study was carried out on immature cumulus-oocyte complexes (COCs) extracted from slaughterhouse ovaries.
- The oocytes were matured in vitro through the CAPA-IVM technique with two forms of pre-maturation: a short 6-hour procedure and a longer 24-hour procedure. These were compared against standard IVM.
- The matured oocytes from all three groups were subjected to several analyses: calcium-releasing potential, single-oocyte proteomics, and post-fertilization embryo development.
- The developed blastocysts were genetically analyzed to detect chromosomal aberrations.
Key Findings
The study demonstrated that CAPA-IVM yielded significantly better maturation rates than the control samples. Furthermore, the shorter form of CAPA-IVM, with just six hours pre-maturation, showed considerably better embryo development potential than the control samples.
- Importantly, the genetic analysis of the resulting blastocysts revealed a high rate of euploidy (normal number of chromosomes) regardless of the maturation conditions.
- The majority of the fertilized oocytes exhibited non-continuous patterns of calcium oscillation, irrespective of the maturation technique used.
- Proteomics analysis revealed essentially similar landscapes between mature oocytes from the short CAPA-IVM and the standard IVM, though four enriched gene sets were identified in the short CAPA-IVM, relating to cytoskeleton regulation, ribosomal function, and cytosolic components.
Implications of the Research
These findings suggest that CAPA-IVM could be a significant tool in improving the quality and developmental competency of oocytes. The evidence of high rates of euploidy indicates that this technique does not exacerbate genetic abnormalities. However, more adjustments and fine-tuning of the culture conditions may be required to make full, effective use of such IVM systems. Considering that the physiological characteristics of horse reproduction closely mirror that of humans, these findings could potentially provide valuable insights that could advance human artificial reproductive technologies.
Cite This Article
Publication
Researcher Affiliations
- Ghent-Fertility and Stem Cell Team (G-FaST), Department for Reproductive Medicine, Department of Human Structure and Repair, Ghent University Hospital, Corneel Heymanslaan 10, 9000 Ghent, Belgium.
- Department of Internal Medicine, Reproduction and Population Medicine, Ghent University, 9820 Merelbeke, Belgium.
- VIB-UGent Center for Medical Biotechnology, Vlaams Instituut voor Biotechnologie (VIB), 9052 Ghent, Belgium.
- Department of Biomolecular Medicine, Ghent University, 9052 Ghent, Belgium.
- Department of Internal Medicine, Reproduction and Population Medicine, Ghent University, 9820 Merelbeke, Belgium.
- Department of Internal Medicine, Reproduction and Population Medicine, Ghent University, 9820 Merelbeke, Belgium.
- Theriogenology Department, Faculty of Veterinary Medicine, Cairo University, Giza 12211, Egypt.
- VIB-UGent Center for Medical Biotechnology, Vlaams Instituut voor Biotechnologie (VIB), 9052 Ghent, Belgium.
- Department of Biomolecular Medicine, Ghent University, 9052 Ghent, Belgium.
- VIB-UGent Center for Medical Biotechnology, Vlaams Instituut voor Biotechnologie (VIB), 9052 Ghent, Belgium.
- Department of Biomolecular Medicine, Ghent University, 9052 Ghent, Belgium.
- Center for Medical Genetics, Ghent University Hospital, 9000 Ghent, Belgium.
- Department of Internal Medicine, Reproduction and Population Medicine, Ghent University, 9820 Merelbeke, Belgium.
- Department of Anatomy and Embryology, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands.
- Department for Reproductive Medicine, Women's Clinic, Ghent University Hospital, Corneel Heymanslaan 10, 9000 Ghent, Belgium.
- Department for Reproductive Medicine, Women's Clinic, Ghent University Hospital, Corneel Heymanslaan 10, 9000 Ghent, Belgium.
- Department of Internal Medicine, Reproduction and Population Medicine, Ghent University, 9820 Merelbeke, Belgium.
- Ghent-Fertility and Stem Cell Team (G-FaST), Department for Reproductive Medicine, Department of Human Structure and Repair, Ghent University Hospital, Corneel Heymanslaan 10, 9000 Ghent, Belgium.
MeSH Terms
- Animals
- Horses
- Oocytes / metabolism
- Oocytes / cytology
- In Vitro Oocyte Maturation Techniques / methods
- In Vitro Oocyte Maturation Techniques / veterinary
- Female
- Embryonic Development
- Blastocyst / metabolism
- Blastocyst / cytology
- Chromosome Aberrations
- Cumulus Cells / cytology
- Cumulus Cells / metabolism
- Sperm Injections, Intracytoplasmic
- Natriuretic Peptide, C-Type / pharmacology
Grant Funding
- BOF.STG.2021.0042.01 / Bijzonder Onderzoeksfonds
- 1177425N / Research Foundation - Flanders
- 2018000504 (GOA030-18 BOF) / Bijzonder Onderzoeksfonds (BOF)
Conflict of Interest Statement
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