title: Maternal obesity in mice not only affects fresh embryo quality but also aggravates injury due to vitrification.
abstract: OBJECTIVE
  The aims of the present study are to identify the mechanism(s) whereby obesity impairs fresh embryos and to clarify the effects of vitrification on lipid droplet content within embryos from maternally obese mice.
  
  
  METHODS
  The diet-induced obesity mouse model was established, and the zygotes were captured and cultured to day 3. The eight-cell embryos were selected and divided into fresh and vitrified groups. The blastocysts derived from fresh embryos were used as a control. The expression profiles of endoplasmic reticulum (ER) stress genes (Atf4, Grp78, and Hsp70) and other genes (MnSOD, p53, Gadd45g, caspase-3, IGF-II, ZO-1, and E-cadherin) on day-3 fresh and post-warming eight-cell embryos from obese and control groups were determined. For day-5 fresh blastocysts and blastocysts previously vitrified on day 3, the expression profiles for all of the above genes were also determined.
  
  
  RESULTS
  For the fresh group, obesity significantly upregulated Hsp70, p53, IGF-II, and ZO-1 expression in embryos on day 3 and notably upregulated Atf4, MnSOD, Gadd45g, caspase-3, ZO-1, and E-cadherin expression in blastocysts on day 5. For vitrified ones, obesity significantly upregulated Atf4, MnSOD, and Gadd45g expression in embryos on day 3 and notably upregulated Hsp70 expression and downregulated MnSOD in day 5 blastocysts previously vitrified on day 3.
  
  
  CONCLUSIONS
  Obesity impairs fresh embryos and aggravates embryonic vitrification injury at a molecular level.
authors.affiliation: Reproductive Centre of Liuzhou Municipal Maternity and Child Healthcare Hospital, Liuzhou, 545000, People's Republic of China.
authors.forename: Wenhong
authors.initials: W
authors.lastname: Ma
authors.affiliation: Center for Reproductive Medicine, Sixth Affiliated Hospital of Sun Yat-sen University, 17th Shou-gou-ling Road, Guangzhou, 510655, People's Republic of China.
authors.forename: Xingfang
authors.initials: X
authors.lastname: Huang
authors.affiliation: Center for Reproductive Medicine, Sixth Affiliated Hospital of Sun Yat-sen University, 17th Shou-gou-ling Road, Guangzhou, 510655, People's Republic of China.
authors.forename: Xing
authors.initials: X
authors.lastname: Yang
authors.affiliation: Center for Reproductive Medicine, Sixth Affiliated Hospital of Sun Yat-sen University, 17th Shou-gou-ling Road, Guangzhou, 510655, People's Republic of China. Lxyzy@263.net.
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Liang
mesh_terms: D000818:Animals; D001755:Blastocyst / Q000473:pathology*; D015925:Cryopreservation; D004624:Embryo Transfer; D047108:Embryonic Development / Q000235:genetics*; D000091342:Endoplasmic Reticulum Chaperone BiP; D005260:Female; D018507:Gene Expression Regulation, Developmental / Q000235:genetics; D006801:Humans; D066292:Lipid Droplets / Q000378:metabolism / Q000473:pathology; D033261:Maternal-Fetal Relations; D051379:Mice; D008820:Mice, Obese; D009765:Obesity / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D058989:Vitrification
keywords: Blastocyst; Embryo; Obesity; Vitrification injury