title: Early overfeed-induced obesity leads to brown adipose tissue hypoactivity in rats.
abstract: OBJECTIVE
  Brown adipose tissue activation has been considered a potential anti-obesity mechanism because it is able to expend energy through thermogenesis. In contrast, white adipose tissue stores energy, contributing to obesity. We investigated whether the early programming of obesity by overfeeding during lactation changes structure of interscapular brown adipose tissue in adulthood and its effects on thermogenesis.
  
  
  METHODS
  Birth of litters was considered day 0. On day 2, litter size was adjusted to normal (9 pups) and small (3 pups) litters. On day 21, the litters were weaned. A temperature transponder was implanted underneath interscapular brown adipose tissue pads of 81-day-old animals; local temperature was measured during light and dark periods between days 87 and 90. The animals were euthanized, and tissue and blood samples were collected for further analysis. The vagus and retroperitoneal sympathetic nerve activity was recorded.
  
  
  RESULTS
  Small litter rats presented significant lower interscapular brown adipose tissue temperature during the light (NL 37.6°C vs. SL 37.2°C) and dark (NL 38°C vs. SL 37.6°C) periods compared to controls. Morphology of small litter brown adipose tissue showed fewer lipid droplets in the tissue center and more and larger in the periphery. The activity of vagus nerve was 19,9% greater in the small litter than in control (p<0.01), and no difference was observed in the sympathetic nerve activity. In adulthood, the small litter rats were 11,7% heavier than the controls and presented higher glycemia 13,1%, insulinemia 70% and corticosteronemia 92,6%.
  
  
  CONCLUSIONS
  Early overfeeding programming of obesity changes the interscapular brown adipose tissue structure in adulthood, leading to local thermogenesis hypoactivity, which may contribute to obesity in adults.
authors: Laboratory of Secretion Cell Biology, Department of Biotechnology, Genetics and Cell Biology, State University of Maringá - Maringá/PR, Brazil.
authors: Douglas L
authors: DL
authors: de Almeida
authors: Gabriel S
authors: GS
authors: Fabrício
authors: Amanda B
authors: AB
authors: Trombini
authors: Audrei
authors: A
authors: Pavanello
authors: Laize P
authors: LP
authors: Tófolo
authors: Tatiane A
authors: TA
authors: da Silva Ribeiro
authors: Paulo C
authors: PC
authors: de Freitas Mathias
authors: Kesia
authors: K
authors: Palma-Rigo
mesh_terms: D002001:Adipose Tissue, Brown / Q000378:metabolism / Q000473:pathology*; D000818:Animals; D000831:Animals, Newborn; D019540:Area Under Curve; D001786:Blood Glucose / Q000032:analysis; D001831:Body Temperature; D001835:Body Weight; D003345:Corticosterone / Q000097:blood; D004435:Eating; D005260:Female; D007328:Insulin / Q000097:blood; D008098:Litter Size; D008297:Male; D009765:Obesity / Q000209:etiology; D012372:ROC Curve; D051381:Rats; D017208:Rats, Wistar; D022722:Thermogenesis; D014630:Vagus Nerve / Q000378:metabolism; D014886:Weaning
chemical_list: D001786:Blood Glucose; D007328:Insulin; D003345:Corticosterone