Exposing Mouse Oocytes to MitoQ During In Vitro Maturation Improves Maturation and Developmental Competence

Document Type: Research Paper

Authors

1 Department of Anatomical Sciences, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.

2 Department of Anatomical Sciences, School of medicine, Tehran university of medical science, Tehran, Iran

3 Department of animal and marine biotechnology, National institute of genetic Engineering and Biotechnology, Tehran, Iran.

4 Department of Anatomical Sciences, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran

5 Fertility and Infertility Research Center, Hormozgan University of Medical Science, Bandar Abbas, Iran

6 Department of Anatomical Sciences, School of medicine, Tehran University of medical sciences, Tehran, Iran.

7 Cellular and Molecular Biology Research Center, School of Medicine, Shahid Beheshti University of Medical SciencesTehran, Iran.

8 Department of animal and marine biotechnology, National institute of genetic Engineering and Biotechnology, Tehran, Iran

Abstract

Abstract
Background: Mitochondrion is the main indicator of oocyte quality and one of the components of oocyte, which is sensitive to oxidative damage during the maturation process. Mitoquinone mesylate (MitoQ) is a strong antioxidant targeting mitochondria as well as anti-apoptotic agent. However, the effect of MitoQ on the quality of oocytes during in vitro maturation (IVM) is still unknown.
Objective: This study investigated the possible effects of MitoQ on maturation and developmental competency in mice oocytes.
Materials and Methods: The oocytes were collected at germinal vesicle stage from 6-8-week old female NMRI mice and then cultured in TCM-199 medium supplemented with 0, 0.01, 0.02 and 0.04 µM MitoQ. The sham group was treated with DMSO (0.01% v.v). Then intracellular Glutathione (GSH), reactive oxygen species (ROS) levels, mitochondria membrane potential (ΔΨm), as well as in vitro fertilization (IVF) rate in the 18-20 h matured oocytes and metaphase II (MII) oocytes (in vivo-control), were assessed.
Results: The results showed that between three dose of MitoQ, the 0.02 µM significantly increased nuclear maturation rate, GSH level, fertilization rate and blastulation (92.6, 231.7, 90.19 and 81.66%, respectively) than the in vitro-control (71.14, 152, 78.84 and 73.50%, respectively) and more comparable to that of the in vivo matured oocytes (100, 243.5, 92.10 and 83%, respectively). Also, the mitochondria membrane potential in the 0.02 µM MitoQ was significantly higher compared with those in the other groups (4.4). However, the intracellular ROS level in 0.02 µM MitoQ was significantly decreased (38.72%) compared to in vitro-control (82.2%) and was similar to the in vivo-control (33.5%).
Conclusion: The results indicated that supplementation of IVM medium with MitoQ (specially 0.02 µM) enhance maturation and fertilization rate. In conclusion, MitoQ might be considered as a novel component that could be added to IVM media.

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