title: Obesity is associated with acute inflammation in a sample of adolescents.
abstract: BACKGROUND
  Obesity is associated with a mild chronic inflammatory response, which has been suggested to be pivotal in the development of cardiometabolic alterations of obesity. However, little is known about the involvement of acute inflammation.
  
  
  OBJECTIVE
  To evaluate whether circulating neutrophils, markers of acute inflammation, are associated (quantitatively and qualitatively) with adolescent obesity and whether leptin modulates these associations.
  
  
  METHODS
  We assessed 528 adolescents (16.8 yr old, 47% females), without chronic/acute illness. We measured anthropometry and dual energy X-ray absorptiometry and calculated fat mass percentage (FM%). Fasting serum glucose, high-density lipoprotein (HDL)-cholesterol, and triglycerides were used with blood pressure and waist circumference to compute a metabolic z-score. Leukocyte and neutrophil counts were obtained, together with levels of serum leptin. In a subsample of 23 males, flow cytometry was used to assess degranulation (CD66b expression) of neutrophils.
  
  
  RESULTS
  Female sex and obesity were positively related to mean neutrophil counts (p < 0.05). When accounting for sex and weight status, leptin was associated with neutrophil counts (p < 0.05), partially explaining the association between obesity and neutrophil counts. Neutrophil counts were related to metabolic risk z-scores, controlling for fat mass. Participants with elevated FM% showed more neutrophil degranulation than controls (p < 0.05).
  
  
  CONCLUSIONS
  Participants with increased adiposity had higher circulating neutrophil counts, suggesting acute inflammation. Furthermore, the neutrophils showed more degranulation, indicating inflammation. Obesity-induced alteration of the adipose secretory pattern (i.e., changes in leptin levels) could be involved in acute inflammation.
authors.affiliation: Public Health Unit, Institute of Nutrition and Food Technology (INTA), University of Chile, Santiago, Chile.
authors.forename: Marcela
authors.initials: M
authors.lastname: Reyes
authors.forename: Cristina
authors.initials: C
authors.lastname: Quintanilla
authors.forename: Raquel
authors.initials: R
authors.lastname: Burrows
authors.forename: Estela
authors.initials: E
authors.lastname: Blanco
authors.forename: Mariana
authors.initials: M
authors.lastname: Cifuentes
authors.forename: Sheila
authors.initials: S
authors.lastname: Gahagan
mesh_terms: D000273:Adipose Tissue / Q000276:immunology* / Q000378:metabolism; D050154:Adiposity; D000293:Adolescent; D015992:Body Mass Index; D002097:C-Reactive Protein / Q000032:analysis; D002677:Chile / Q000453:epidemiology; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D020738:Leptin / Q000097:blood* / Q000378:metabolism; D008297:Male; D024821:Metabolic Syndrome / Q000453:epidemiology; D009504:Neutrophils / Q000276:immunology / Q000378:metabolism; D015434:Panniculitis / Q000097:blood / Q000209:etiology* / Q000276:immunology / Q000503:physiopathology; D063766:Pediatric Obesity / Q000503:physiopathology*; D012307:Risk Factors; D012720:Severity of Illness Index; D015854:Up-Regulation
chemical_list: D020738:Leptin; D002097:C-Reactive Protein
keywords: acute inflammation; adolescents; leukocytes; neutrophils; obesity