The effects of melatonin on bovine uniparental embryos development in vitro and the hormone secretion of COCs

Shujuan Wang; Baoru Liu; Wenju Liu; Yao Xiao; Hualin Zhang; Liguo Yang

doi:10.7717/peerj.3485

The effects of melatonin on bovine uniparental embryos development in vitro and the hormone secretion of COCs

PeerJ. 2017 Jul 7:5:e3485. doi: 10.7717/peerj.3485. eCollection 2017.

Authors

Shujuan Wang^{1

2}, Baoru Liu², Wenju Liu¹, Yao Xiao², Hualin Zhang², Liguo Yang²

Affiliations

¹ College of Animal Science, Anhui Science and Technology University, Bengbu, Anhui, China.
² Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Huazhong Agriculture University, Wuhan, Hubei, China.

Abstract

Melatonin is a unique multifunctional molecule that mediates reproductive functions in animals. In this study, we investigated the effects of melatonin on bovine parthenogenetic and androgenetic embryonic development, oocyte maturation, the reactive oxygen species (ROS) levels in parthenogenetic and androgenetic embryos and cumulus-oocyte complexes (COCs) hormone secretion with melatonin supplementation at four concentrations (0, 10, 20, and 30 pmol/mL), respectively. The results showed that melatonin significantly promoted the rates of bovine parthenogenetic and androgenetic embryonic cleavage and morula and blastocysts development (P < 0.05). The rate of cleavage was higher in the androgenetic embryo than that in the parthenogenetic embryo. Compared with the parthenogenetic embryos, the androgenetic embryos had a poor developmental competence from morula to blastocyst stage. Moreover, the levels of ROS were significantly lower in the parthenogenetic and androgenetic embryoes with melatonin-treated group than that of the control group (P < 0.05). Melatonin supplemented significantly increased the maturation rate of oocyte in vitro (P < 0.05). More importantly, melatonin significantly promoted the secretion of progesterone and estradiol by COCs (P < 0.05). To reveal the regulatory mechanism of melatonin on steroids synthesis, we found that steroidogenic genes (CYP11A1, CYP19A1 and StAR) were upregulated, suggesting that melatonin regulated estradiol and progesterone secretion through mediating the expression of steroidogenic genes (CYP11A1, CYP19A1 and StAR). In addition, MT1 and MT2 were identified in bovine early parthenogenetic and androgenetic embryos using western blot. It could be concluded that melatonin had beneficial effects on bovine oocyte in vitro maturation, COC hormone secretion, early development of subsequent parthenogenetic and androgenetic embryos. It is inferred that melatonin could be used to enhance the efficiency of in vitro developed embryos.

Keywords: Androgenetic embryo; Bovine; COCs; Hormone; Melatonin; Parthenogenetic embryo; ROS.

Associated data

figshare/10.6084/m9.figshare.4653460.v1

Grants and funding

This study was financially supported by the Natural Science Foundation of China (31301972), Natural Science Foundation of Anhui Province (1308085QC66), Earmarked Fund for Modern Agro-industry Technology Research System (CARS-37-04B) and the Scientific Special Expenditure for Non-profit Public Industry (Agriculture) (201003060).