title: Improvement of embryonic development and production of offspring by transferring meiosis-II chromosomes of senescent mouse oocytes into cytoplasts of young mouse oocytes.
abstract: OBJECTIVE
  The effects of reciprocal transplantation of meiosis-II chromosomes between senescent and young mouse oocytes were evaluated based on pre- and post-implantation development ability of resultant embryos.
  
  
  METHODS
  Karyoplasts including meiosis-II chromosomes of oocytes from senescent Rockefeller mouse/Ms-Rb(6, 15) females (10 to 12 months, age-related infertile mice) were transferred into cytoplasts of oocytes from young F(1) females (3 to 5 months). Reconstructed oocytes were fertilized in vitro, and then the resultant embryos were cultured in vitro and transferred to recipient mice.
  
  
  RESULTS
  The reconstructed oocytes that consisted of aged-karyoplasts and young-cytoplasts showed significantly improved embryonic development (from 23.2% to 30.0%) and development to term (from 6.3% to 27.1%, P < 0.05) as compared with the oocytes reconstructed from young-karyoplasts and aged-cytoplasts.
  
  
  CONCLUSIONS
  The present study showed successful rejuvenation for age-related infertility using transplantation of meiosis-II chromosomes in animal experimental models.
authors.affiliation: United Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology, Fuchu-shi, Tokyo, Japan. akinori.mitsui@kyowa-kirin.co.jp
authors.forename: Akinori
authors.initials: A
authors.lastname: Mitsui
authors.forename: Midori
authors.initials: M
authors.lastname: Yoshizawa
authors.forename: Hiromichi
authors.initials: H
authors.lastname: Matsumoto
authors.forename: Emiko
authors.initials: E
authors.lastname: Fukui
mesh_terms: D000367:Age Factors; D000375:Aging / Q000235:genetics*; D000818:Animals; D033481:Chromosomes, Mammalian / Q000235:genetics*; D003593:Cytoplasm / Q000502:physiology; D047108:Embryonic Development / Q000235:genetics*; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods; D007247:Infertility, Female / Q000235:genetics / Q000503:physiopathology / Q000628:therapy*; D008297:Male; D008540:Meiosis / Q000235:genetics; D051379:Mice; D053652:Nuclear Transfer Techniques; D009865:Oocytes / Q000502:physiology; D011247:Pregnancy; D018873:Pregnancy Rate