Oxidative Stress Impact on Oocyte Maturation and Embryonic Development

Oxidative stress, defined by an excess of reactive oxygen species (ROS) relative to antioxidant defences, poses a significant challenge to both oocyte maturation and early embryonic development. During in vitro culture, elevated ROS levels can impair mitochondrial function, disrupt spindle assembly, damage lipids and proteins, and trigger apoptotic pathways. In the oocyte, this manifests as compromised nuclear and cytoplasmic maturation, altered cumulus cell expansion and reduced competence for fertilisation. Following fertilisation, embryos subjected to oxidative insult exhibit delayed cleavage, lower blastocyst formation rates and diminished cell numbers, which ultimately undermines implantation potential. Research has therefore focused on both endogenous and exogenous antioxidant strategies to restore redox balance, ranging from small‐molecule scavengers and natural flavonoids to biocompatible nanoparticles and pathway‐specific agents. Interdisciplinary efforts now integrate epigenetic analyses and mitochondrial dynamics to reveal how redox modulation can enhance developmental competence while ensuring genomic integrity. The global importance of this work is reflected in applications spanning assisted reproductive technologies, livestock breeding efficiency and human fertility preservation.

Research from Nature Portfolio

Green synthesis of iron oxide nanoparticles using botanical extracts has demonstrated a capacity to shield porcine oocytes from exogenous ROS during in vitro maturation, leading to higher fertilisation and blastocyst rates compared with chemically synthesised particles. By reducing hydrogen peroxide and superoxide production, these biogenic nanoparticles preserve mitochondrial membrane potential and support successive cleavage stages.

The mitochondria‐targeted superoxide scavenger Mito-TEMPO has been shown to rescue developmental competence in porcine embryos with high lipid content by lowering superoxide accumulation. Treatment restores mitochondrial aggregation, enhances ATP generation and increases blastocyst formation, thus underlining the critical role of mitochondrial redox homeostasis in embryo viability.

Supplementation with l-ascorbic acid during porcine oocyte maturation not only reduces ROS but also initiates global epigenetic reprogramming of DNA, RNA and histones. These modifications enhance first polar body extrusion, upregulate developmental gene expression and improve subsequent cleavage and blastocyst rates, revealing a dual antioxidant and epigenetic mechanism.

Oxidative Stress Impact on Oocyte Maturation and Embryonic Development publication trend

The graph below shows the total number of articles in oxidative stress impact on oocyte maturation and embryonic development across all publications each year (not limited to Nature Index journals).

Technical terms

Reactive oxygen species (ROS): Chemically reactive molecules containing oxygen, including superoxide and hydrogen peroxide, which can damage cellular components.

Glutathione (GSH): A tripeptide antioxidant that neutralises ROS and maintains redox balance within cells.

Mitochondrial membrane potential (MMP): The electrochemical gradient across the inner mitochondrial membrane, essential for ATP synthesis and indicative of mitochondrial health.

Cumulus–oocyte complex (COC): The oocyte together with surrounding cumulus cells, whose expansion reflects oocyte maturation status.

Blastocyst: The stage of embryonic development characterised by a fluid-filled cavity and segregation into inner cell mass and trophectoderm, marking readiness for implantation.

References

1. Oocyte maturation, fertilization, and embryo development in vitro by green and chemical iron oxide nanoparticles: a comparative study. Scientific Reports (2024).
2. Mito-TEMPO improves development competence by reducing superoxide in preimplantation porcine embryos. Scientific Reports (2018).
3. Ascorbic acid induces global epigenetic reprogramming to promote meiotic maturation and developmental competence of porcine oocytes. Scientific Reports (2018).
4. Chrysoeriol Improves the Early Development Potential of Porcine Oocytes by Maintaining Lipid Homeostasis and Improving Mitochondrial Function. Antioxidants (2024).
5. Anethole improves the developmental competence of porcine embryos by reducing oxidative stress via the sonic hedgehog signaling pathway. Journal of Animal Science and Biotechnology (2023).
6. Ferulic Acid Enhances Oocyte Maturation and the Subsequent Development of Bovine Oocytes. International Journal of Molecular Sciences (2023).