DEFINING THE ROLE OF ADDING ANTIOXIDANTS IN EMBRYO CULTURE MEDIA ON PRE-IMPLANTATION EMBRYO DEVELOPMENTS

Abstract

ABSTRACT BACKGROUND The metabolic activity of embryos and their capacity to adapt to their environment is affected by culture conditions throughout early developmental stages. In vitro embryo development, oxidative stress causes an increase in changes in gene expression, cell apoptosis, and decreased embryo quality by generating too many reactive oxygen species (ROS) free radicals. Better embryo metabolism and decreased ROS generation are likely to be responsible for improved embryo growth in low oxygen conditions. In embryo culture, several ways reduce ROS levels and protect the embryo against oxidative stress. The most effective way to reduce ROS levels is by adding antioxidants to embryo culture media. Antioxidants are efficient in regulating intra- and extra-embryonic environments to reduce ROS toxicity and hence improve embryo development, increase the blastocyst formation rate, and protect the embryo from cell apoptosis. OBJECTIVES The overall objective of the current study is to perform a literature review to define the role of adding antioxidants in embryo culture media on preimplantation embryo development. METHODS To find all relevant papers, the author used an electronic search of one internet database. An extensive electronic database search employing PubMed to find studies that examined the effects of adding antioxidants on embryo culture media. Studies were selected based on adding antioxidants to the culture media post-fertilisation, as appose to exposure of the gametes, and which had been published in 2011 and 2021. To be eligible for inclusion in the objective studies had to be observational of the type of the antioxidant, the effective dose, and the significant effects. RESULTS The database search and title review yielded a total of 276 publications of interest. Title and abstracts analysis was then performed, and 212 citations were excluded as it was evident, they did not meet the inclusion criteria. The remaining 64 articles were screened by abstract review. Then, full manuscripts and assessments were obtained for all 64 articles for inclusion. CONCLUSIONS According to the reviewed literature, adding antioxidants at a specific dosage can preserve embryo development in vitro by scavenging free radicals, regulating signalling pathways, increasing mitochondrial activity, and reducing cell apoptosis. As a result, it appears that using antioxidants in human embryo culture media might be used as a non-invasive and successful way to promote human embryo development in vitro in the future, however, more research, including clinical trials, is needed to validate this.