title: Adipose tissue-derived adiponectin expression is significantly associated with increased post operative mortality in horses undergoing emergency abdominal surgery.
abstract: BACKGROUND
  Adipose tissue is an important source of inflammatory cytokines (adipokines) and adiposity has been identified as having a significant effect on human morbidity and mortality. Obesity is also an emerging welfare problem in the UK horse population, but the role that it plays in secondary diseases is unclear.
  
  
  OBJECTIVE
  To examine the expression of inflammation-related adipokine genes in retroperitoneal adipose tissue of horses undergoing emergency abdominal surgery and to explore associations with adiposity and post operative survival.
  
  
  METHODS
  Retroperitoneal adipose tissue samples were obtained from 76 horses undergoing emergency abdominal surgery. Real-time PCR was used to measure gene expression for leptin, adiponectin, tumour necrosis factor-alpha, macrophage chemoattractant protein-1, macrophage inhibitory factor, serum amyloid A, haptoglobin and interleukin-1. Multivariate patterns of adipokine expression were explored with principal component analysis (PCA), whilst univariable associations with post operative survival were tested in a Cox proportional hazards model.
  
  
  RESULTS
  Leptin gene expression was higher in overweight and obese horses than in lean animals. Expression of mRNA encoding adiponectin mRNA in visceral adipose tissue was positively associated with increased post operative mortality (hazard ratio 1.31, 95% CI 1.05-1.65). However, PCA did not demonstrate multivariable patterns of adipokine gene expression from visceral adipose tissue associated with body mass index or with survival.
  
  
  CONCLUSIONS
  In horses presented with acute intestinal disease, increased adiponectin gene expression from retroperitoneal adipose tissue is associated with an increased risk of mortality. Obesity assessed by BMI had no association with increased post operative mortality in horses with primary gastrointestinal disease.
  
  
  CONCLUSIONS
  Further study is warranted on the expression and effects of adipokines, particularly adiponectin, and correlation with postoperative outcome.
authors.affiliation: School of Veterinary Science, Faculty of Health and Life Sciences, University of Liverpool, UK. mjpacker@liverpool.ac.uk
authors.forename: M J
authors.initials: MJ
authors.lastname: Packer
authors.forename: A J
authors.initials: AJ
authors.lastname: German
authors.forename: L
authors.initials: L
authors.lastname: Hunter
authors.forename: P
authors.initials: P
authors.lastname: Trayhurn
authors.forename: C J
authors.initials: CJ
authors.lastname: Proudman
mesh_terms: D052242:Adiponectin / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D013505:Digestive System Surgical Procedures / Q000009:adverse effects / Q000662:veterinary*; D004630:Emergencies / Q000662:veterinary*; D005260:Female; D005786:Gene Expression Regulation / Q000502:physiology; D006734:Horse Diseases / Q000401:mortality / Q000601:surgery*; D006736:Horses; D050152:Intra-Abdominal Fat / Q000378:metabolism*; D008297:Male; D009765:Obesity / Q000662:veterinary; D011183:Postoperative Complications / Q000401:mortality / Q000662:veterinary*
chemical_list: D052242:Adiponectin