title: Chop-deficient mice showed increased adiposity but no glucose intolerance.
abstract: OBJECTIVE
  CCAAT/enhancer binding protein (C/EBP) homologous protein (CHOP)-10/growth arrest and DNA damage 153 is a dominant-negative member of the C/EBP transcription family and inhibits adipogenesis in vitro. The study was undertaken to determine the role of CHOP in obesity in vivo.
  
  
  METHODS
  Changes in daily food consumption and body weight were measured. The weight of white and brown adipose tissue was compared between Chop(+/+) and (-/-) mice fed normal chow or a high-fat diet. Glucose and insulin tolerance tests were done, and serum adipocytokine was measured to determine their metabolic state. Fat cell size of subcutaneous and mesenteric adipose tissue was microscopically observed. C/EBP expression in white adipose tissue was examined by Western blot.
  
  
  RESULTS
  Female Chop(-/-) mice had significantly greater body weight and adiposity than Chop(+/+) mice, although daily food intake and rectal temperature did not differ. In comparison with Chop(+/+) mice, glucose tolerance and insulin sensitivity did not differ in female Chop(-/-) mice, but levels of plasma leptin and adiponectin were higher. High-fat diet feeding resulted in obesity in female Chop(+/-) and (-/-) mice, although caloric intake did not differ from that of Chop(+/+) mice. Fat cell area was larger in mesenteric fat but not in subcutaneous fat in Chop(-/-) mice fed a high-fat diet. C/EBPbeta and the 30-kDa form of C/EBPalpha expressions were increased in parametrial fat of Chop(-/-) mice, but the 42-kDa form of C/EBPalpha expression was lower than in Chop(+/+) mice.
  
  
  CONCLUSIONS
  CHOP deficiency causes obesity in female animals without severe metabolic disorders, and C/EBP's expression may be considered to participate in the process.
authors.affiliation: Department of Medicine and Molecular Science, CREST Japan Science and Technology Agency, Gunma, Japan.
authors.forename: Yasuyo
authors.initials: Y
authors.lastname: Ariyama
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Shimizu
authors.forename: Tetsurou
authors.initials: T
authors.lastname: Satoh
authors.forename: Takafumi
authors.initials: T
authors.lastname: Tsuchiya
authors.forename: Shuichi
authors.initials: S
authors.lastname: Okada
authors.forename: Seiichi
authors.initials: S
authors.lastname: Oyadomari
authors.forename: Masataka
authors.initials: M
authors.lastname: Mori
authors.forename: Masatomo
authors.initials: M
authors.lastname: Mori
mesh_terms: D000818:Animals; D001835:Body Weight / Q000235:genetics*; D005951:Glucose Tolerance Test; D051379:Mice; D018345:Mice, Knockout; D023421:Models, Animal; D009765:Obesity / Q000235:genetics*; D051742:Transcription Factor CHOP / Q000172:deficiency*
chemical_list: C497250:Ddit3 protein, mouse; D051742:Transcription Factor CHOP