title: Zinc deficiency during in vitro maturation of porcine oocytes causes meiotic block and developmental failure.
abstract: The present study investigated the effects of zinc deficiency during in vitro maturation (IVM) of porcine oocytes. Zinc deficiency was induced by administering the membrane‑permeable zinc chelator N,N,N',N'‑tetrakis‑(2‑pyridylmethyl)‑ethylendiamine (TPEN). First, the effects of zinc deficiency during IVM on a TPEN‑treated group and a TPEN+zinc-treated group compared with a control group were assessed. The oocyte maturation rates and subsequent embryonic developmental competence of the TPEN+zinc‑treated oocytes were similar to those of the control oocytes (metaphase II [MII] rate, 93.0 and 92.7%, respectively, and blastocyst [BL] formation rate, 42.0 and 40.0%, respectively). These results were significantly different from those obtained for the TPEN‑treated oocytes (MII rate, 0.61%; BL formation rate, 0%). Although the TPEN‑treated oocytes were arrested at metaphase I (MI), the distribution of microtubules was normal. However, microfilament formation was abnormal in the TPEN‑treated oocytes. Furthermore, the effect of a temporary zinc deficiency during IVM on oocyte maturation and subsequent embryonic development was assessed. TPEN (10 µM) was added to the IVM medium for 0, 7, 15 or 22 h. The 0 h‑treated oocytes showed an 83.9% MII rate, while the 7 h‑treated oocytes had a significantly lower MII rate (44.8%). Most of the 15- and 22 h‑treated oocytes were arrested at MI (MI rate: 98.0 and 97.2%, respectively; MII rate, 0% in both groups). Reductions in the BL formation were dependent on the TPEN treatment duration (29.3, 9.2, 0, and 0% after 0, 7, 15 and 22 h, respectively). In conclusion, zinc is an essential element for successful oocyte maturation and embryonic development in pigs. Zinc deficiency caused a meiotic block and had lasting effects on early embryonic development.
authors.affiliation: Laboratory of Veterinary Embryology and Biotechnology (VETEMBIO), College of Veterinary Medicine, Chungbuk National University, Cheongju, Chungbuk 361‑763, Republic of Korea.
authors.forename: Yubyeol
authors.initials: Y
authors.lastname: Jeon
authors.affiliation: Laboratory of Veterinary Embryology and Biotechnology (VETEMBIO), College of Veterinary Medicine, Chungbuk National University, Cheongju, Chungbuk 361‑763, Republic of Korea.
authors.forename: Junchul David
authors.initials: JD
authors.lastname: Yoon
authors.affiliation: Laboratory of Veterinary Embryology and Biotechnology (VETEMBIO), College of Veterinary Medicine, Chungbuk National University, Cheongju, Chungbuk 361‑763, Republic of Korea.
authors.forename: Lian
authors.initials: L
authors.lastname: Cai
authors.affiliation: Laboratory of Veterinary Embryology and Biotechnology (VETEMBIO), College of Veterinary Medicine, Chungbuk National University, Cheongju, Chungbuk 361‑763, Republic of Korea.
authors.forename: Seon-Ung
authors.initials: SU
authors.lastname: Hwang
authors.affiliation: Laboratory of Veterinary Embryology and Biotechnology (VETEMBIO), College of Veterinary Medicine, Chungbuk National University, Cheongju, Chungbuk 361‑763, Republic of Korea.
authors.forename: Eunhye
authors.initials: E
authors.lastname: Kim
authors.affiliation: Laboratory of Veterinary Embryology and Biotechnology (VETEMBIO), College of Veterinary Medicine, Chungbuk National University, Cheongju, Chungbuk 361‑763, Republic of Korea.
authors.forename: Zhong
authors.initials: Z
authors.lastname: Zheng
authors.affiliation: Laboratory of Veterinary Biochemistry and Molecular Biology, College of Veterinary Medicine, Chungbuk National University, Cheongju, Chungbuk 361‑763, Republic of Korea.
authors.forename: Euibae
authors.initials: E
authors.lastname: Jeung
authors.affiliation: Laboratory of Theriogenology, College of Veterinary Medicine, Kangwon National University, Chuncheon, Gangwon 200-710, Republic of Korea.
authors.forename: Eunsong
authors.initials: E
authors.lastname: Lee
authors.affiliation: Laboratory of Veterinary Embryology and Biotechnology (VETEMBIO), College of Veterinary Medicine, Chungbuk National University, Cheongju, Chungbuk 361‑763, Republic of Korea.
authors.forename: Sang-Hwan
authors.initials: SH
authors.lastname: Hyun
mesh_terms: D000818:Animals; D001755:Blastocyst / Q000166:cytology / Q000187:drug effects; D002478:Cells, Cultured; D047108:Embryonic Development / Q000187:drug effects; D005029:Ethylenediamines / Q000009:adverse effects; D005978:Glutathione / Q000378:metabolism; D008677:Metaphase; D009865:Oocytes / Q000166:cytology / Q000187:drug effects*; D017382:Reactive Oxygen Species / Q000378:metabolism; D013552:Swine; D015032:Zinc / Q000172:deficiency*
chemical_list: D005029:Ethylenediamines; D017382:Reactive Oxygen Species; D005978:Glutathione; D015032:Zinc; C044387:N,N,N',N'-tetrakis(2-pyridylmethyl)ethylenediamine