Oocyte maturation under a biophoton generator improves preimplantation development of pig embryos derived by parthenogenesis and somatic cell nuclear transfer

Lee, DJoohyeong; Shin, Hyeji; Lee, Wonyou; Lee, Seung Tae; Lee, Geun-Shik; Hyun, Sang-Hwan; Lee, Eunsong

doi:2017.57.2.89

Korean J Vet Res > Volume 57(2); 2017 > Article

Original Article

Korean Journal of Veterinary Research 2017;57(2):89-95.
DOI: https://doi.org/10.14405/kjvr.2017.57.2.89 Published online August 11, 2017.

Oocyte maturation under a biophoton generator improves preimplantation development of pig embryos derived by parthenogenesis and somatic cell nuclear transfer

DJoohyeong Lee¹, Hyeji Shin¹, Wonyou Lee², Seung Tae Lee³, Geun-Shik Lee¹, Sang-Hwan Hyun⁴, Eunsong Lee¹

¹Laboratory of Theriogenology, College of Veterinary Medicine, Kangwon National University
²Biolight Corporation
³Department of Animal Life Science and Division of Applied Animal Science, College of Animal Life Science, Kangwon National University
⁴Laboratory of Veterinary Embryology and Biotechnology, Veterinary Medical Center and College of Veterinary Medicine, Chungbuk National University

Abstract

This study was conducted to determine the effects of biophoton treatment during in vitro maturation (IVM) and/or in vitro culture (IVC) on oocyte maturation and embryonic development in pigs. An apparatus capable of generating homogeneous biophoton energy emissions was placed in an incubator. Initially, immature pig oocytes were matured in the biophoton-equipped incubator in medium 199 supplemented with cysteine, epidermal growth factor, insulin, and gonadotrophic hormones for 22 h, after which they were matured in hormone-free medium for an additional 22 hr. Next, IVM oocytes were induced for parthenogenesis (PA) or provided as cytoplasts for somatic cell nuclear transfer (SCNT). Treatment of oocytes with biophoton energy during IVM did not improve cumulus cell expansion, nuclear maturation, intraoocyte glutathione content, or mitochondrial distribution of oocytes. However, biophoton-treated oocytes showed higher (p < 0.05) blastocyst formation after PA than that in untreated oocytes (50.7% vs. 42.7%). In an additional experiment, SCNT embryos produced from biophoton-treated oocytes showed a greater (p < 0.05) number of cells in blastocysts (52.6 vs. 43.9) than that in untreated oocytes. Taken together, our results demonstrate that biophoton treatment during IVM improves developmental competence of PA- and SCNT-derived embryos.

Key Words: biophoton, embryonic development, oocyte maturation, somatic cell nuclear transfer