Insulin–transferrin–selenium (ITS) improves maturation of porcine oocytes in vitro

• Published in: Zygote (Cambridge) Vol. 19; no. 3; pp. 191 - 197
• Main Authors: Hu, Junhe, Ma, Xiaoling, Bao, Jian Chang, Li, Wei, Cheng, De, Gao, Zhimin, Lei, Anmin, Yang, Chunrong, Wang, Huayan
• Format: Journal Article
• Language: English
• Published: Cambridge, UK Cambridge University Press 01.08.2011
• Subjects: Animals; Antioxidants - pharmacology; Cell Nucleus - drug effects; Cell Nucleus - metabolism; Cells, Cultured; Chorionic Gonadotropin - pharmacology; Cytoplasm - drug effects; Cytoplasm - metabolism; Embryo, Mammalian - cytology; Embryo, Mammalian - drug effects; Embryo, Mammalian - metabolism; Embryonic Development - drug effects; Epidermal Growth Factor - pharmacology; Female; Gonadotropins, Equine - pharmacology; Horses; Humans; Hypoglycemic Agents - pharmacology; Immunoenzyme Techniques; Insulin - pharmacology; Oocytes - cytology; Oocytes - drug effects; Oogenesis - drug effects; Pregnancy; Selenium - pharmacology; Swine; Transferrin - pharmacology; Porcine; Porcine oocyte; In vitro maturation; Insulin–transferrin–selenium; Cortical granules
• ISSN: 0967-1994; 1469-8730
• DOI: 10.1017/S0967199410000663

The objective of this study was to determine if insulin–transferrin–selenium (ITS) promoted a nuclear and cytoplasmic maturation of porcine oocytes that better supports subsequent embryonic development. The rate of oocyte in vitro maturation (IVM) in an experimental group treated with hormones for 42 h was significantly increased compared with that in a control group without hormone treatment (47.8% vs. 11.7%, respectively, p < 0.05). Following reduction of the hormone treatment period from 42 h to 21 h, which included both the first 21 h period of hormones treatment (45.4%) and the second 21 h period of hormone treatment (44.8%), the rate of oocyte IVM was still higher than that of the control group (p < 0.05). To improve porcine oocyte nuclear maturation, 1% ITS was added to medium supplemented with hormones. The rate of nuclear maturation in the ITS-treated group was significantly higher than in the ITS-untreated group (78.6% vs. 54.4%, respectively, p < 0.05). ITS treatment also significantly reduced the per cent of oocytes with type I and type III cortical granule (CG) distribution, respectively, and significantly increased the per cent of oocytes with type II CG distribution (85.3%). These observations indicated that the synchronization rates of nuclear and ooplasmic maturation reached 67.04% (78.56 × 85.33%). In conclusion, the combination of modified Tissue Culture Medium-199 (mM199) + 10 ng/ml epidermal growth factor (EGF) + 10 IU/ml pregnant mare serum gonadotrophin (PMSG) + 10 IU/ml human chorion gonadotrophin (hCG) + 2.5 IU/ml follicle stimulating hormone (FSH) + 1% ITS is suitable for culturing porcine oocytes in vitro, and effectively enhances porcine oocyte nuclear and cytoplasmic maturation.