title: Developmental competence of porcine oocytes after in vitro maturation and in vitro culture under different oxygen concentrations.
abstract: In this study, we investigated the effect of two oxygen concentrations (5 and 20%) during in vitro maturation (IVM) and during in vitro culture (IVC) on porcine embryo development and analysed differences in gene expression between cumulus-oocyte complexes matured under 5 or 20% oxygen and the resulting blastocysts cultured under 5% or 20% oxygen following parthenogenetic activation. There was no significant difference in oocyte maturation rate. However, the numbers of resulting blastocysts were significantly increased in the 5% IVC group compared with the 20% IVC group. Moreover, the M20C5 treatment group (23.01%) supported greater blastocyst development compared with the M5C5 (14.32%), M5C20 (10.30%), and M20C20 (17.88%) groups. However, total cell numbers were not significantly different among groups. According to mRNA abundance data of multiple genes, each treatment altered the expression of genes in different patterns. GLUT1, G6PD and LDHA were up-regulated in cumulus cells that had been matured in low oxygen, suggesting a higher glucose uptake and an increase in anaerobic glycolysis, whereas cyclin B1 (CCNB) and MnSOD (Mn-superoxide dismutase) were upregulated in cumulus cells that had been matured in high oxygen, which suggests a higher activity of mitosis-promoting factor and antioxidant response. In spite of these differential effects on cumulus cells, oocytes could mature normally regardless of different oxygen concentrations. Therefore, it can be concluded that high oxygen concentration during in vitro maturation and low oxygen during in vitro culture may alter the expression of multiple genes related to oocyte competence and significantly improves embryo development (p < 0.05) but not blastocyst quality.
authors.affiliation: Department of Theriogenology and Biotechnology, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul 151-742, Korea.
authors.forename: Jung-Taek
authors.initials: JT
authors.lastname: Kang
authors.forename: Mohammad
authors.initials: M
authors.lastname: Atikuzzaman
authors.forename: Dae-Kee
authors.initials: DK
authors.lastname: Kwon
authors.forename: Sol-Ji
authors.initials: SJ
authors.lastname: Park
authors.forename: Su-Jin
authors.initials: SJ
authors.lastname: Kim
authors.forename: Joon-Ho
authors.initials: JH
authors.lastname: Moon
authors.forename: Ok-Jae
authors.initials: OJ
authors.lastname: Koo
authors.forename: Goo
authors.initials: G
authors.lastname: Jang
authors.forename: Byeong-Chun
authors.initials: BC
authors.lastname: Lee
mesh_terms: D000693:Anaerobiosis; D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D002452:Cell Count; D054885:Cumulus Cells / Q000166:cytology / Q000378:metabolism; D056744:Cyclin B1 / Q000235:genetics / Q000378:metabolism; D004558:Electric Stimulation; D004622:Embryo, Mammalian / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D047108:Embryonic Development; D018507:Gene Expression Regulation, Developmental; D051272:Glucose Transporter Type 1 / Q000378:metabolism; D006019:Glycolysis; D059471:In Vitro Oocyte Maturation Techniques / Q000379:methods*; D009865:Oocytes / Q000166:cytology / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D010100:Oxygen / Q000494:pharmacology*; D010312:Parthenogenesis; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D013552:Swine / Q000196:embryology / Q000378:metabolism; D046509:Tissue Culture Techniques
chemical_list: D000975:Antioxidants; D056744:Cyclin B1; D051272:Glucose Transporter Type 1; D012333:RNA, Messenger; D010100:Oxygen