title: L-carnitine enhances oocyte maturation and development of parthenogenetic embryos in pigs.
abstract: The objective was to determine whether adding L-carnitine in IVM/IVC medium enhanced maturation and developmental competence of porcine oocytes in vitro. Oocyte maturation rates did not differ significantly among groups supplemented with 0, 0.25, 0.5, or 1 mg/mL of L-carnitine added during IVM (although 2 mg/mL of L-carnitine reduced maturation rate). Compared with control oocytes, those treated with 0.5 mg/mL of L-carnitine during IVM had greater (P < 0.05) rates of blastocyst formation after parthenogenetic activation, and these blastocysts had less (P < 0.05) apoptosis. Adding 0.5 mg/mL of L-carnitine during IVM also significantly reduced intracellular reactive oxygen species (ROS), and increased glutathione (GSH) concentrations. With or without glucose supplementation, 0.5 mg/mL of L-carnitine in the IVM medium significantly hastened nuclear maturation of oocytes. Moreover, supplementing the IVM medium with either glucose or L-carnitine increased (P < 0.05) percentages of oocytes that reached the metaphase II (MII) stage, relative to a control group. Final maturation rates in IVM medium containing either glucose or L-carnitine were not significantly different. Adding L-carnitine (0 to 2 mg/mL) to IVC medium for activated porcine oocytes did not significantly affect development. However, 0.5 mg/mL of L-carnitine in IVC medium significantly reduced reactive oxygen species levels and apoptosis in activated blastocysts, although glutathione concentrations were not significantly altered. In conclusion, adding L-carnitine during IVM/IVC improved developmental potential of porcine oocytes, and also the quality of parthenogenetic embryos, probably by accelerating nuclear maturation, and preventing oxidative damage and apoptosis.
authors.affiliation: Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture, College of Animal Science and Technology, China Agricultural University, Beijing, People's Republic of China.
authors.forename: G-Q
authors.initials: GQ
authors.lastname: Wu
authors.forename: B-Y
authors.initials: BY
authors.lastname: Jia
authors.forename: J-J
authors.initials: JJ
authors.lastname: Li
authors.forename: X-W
authors.initials: XW
authors.lastname: Fu
authors.forename: G-B
authors.initials: GB
authors.lastname: Zhou
authors.forename: Y-P
authors.initials: YP
authors.lastname: Hou
authors.forename: S-E
authors.initials: SE
authors.lastname: Zhu
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D001755:Blastocyst / Q000502:physiology; D002331:Carnitine / Q000494:pharmacology*; D002467:Cell Nucleus / Q000502:physiology; D046149:Embryo Culture Techniques / Q000662:veterinary; D005260:Female; D005947:Glucose / Q000494:pharmacology; D005978:Glutathione / Q000032:analysis; D059471:In Vitro Oocyte Maturation Techniques / Q000662:veterinary; D009865:Oocytes / Q000737:chemistry / Q000187:drug effects* / Q000502:physiology*; D009866:Oogenesis / Q000187:drug effects; D010312:Parthenogenesis / Q000187:drug effects*; D017382:Reactive Oxygen Species / Q000032:analysis; D034421:Sus scrofa
chemical_list: D017382:Reactive Oxygen Species; D005978:Glutathione; D005947:Glucose; D002331:Carnitine