title: Microparticle increase in severe obesity: not related to metabolic syndrome and unchanged after massive weight loss.
abstract: OBJECTIVE
  To clarify the relationships between circulating microparticles (MPs), leukocyte-platelet aggregates (LPAs), obesity, and metabolic abnormalities and evaluate the effect of losing weight on these parameters.
  
  
  METHODS
  In 151 severely obese women and 60 lean controls, total MPs (annexin-V positive), platelet (annexin V/CD41+) and endothelial (CD31+/CD41-) MPs, and LPAs using flow cytometry, and the presence of metabolic syndrome (MS) were assessed. The effect of weight loss was studied in 32 subjects after a 1 year follow-up.
  
  
  RESULTS
  Total microparticle count, platelet MPs (PMPs) and endothelial MPs (EMPs), and neutrophil-platelet aggregates were significantly increased in obese subjects versus lean controls, independently of the MS. Within obese subjects, there was no significant difference between those having and those not having MS. MPs and LPA counts did not vary significantly in subjects who lost 25% of their excess weight.
  
  
  CONCLUSIONS
  PMPs and EMPs, and LPAs are associated with obesity independently of metabolic abnormalities, but do not significantly change after massive weight loss. Further studies are needed to evaluate the prognostic significance of these observations, as beneficial effects of MPs are currently reported in addition to their initially described deleterious effects.
authors.affiliation: AP-HP, Hôpital Louis Mourier, service d'Hématologie biologique et Transfusion, Colombes, 92700, France; INSERM U770, Hôpital de Bicêtre, Le Kremlin-Bicêtre 94270, France.
authors.forename: Alain
authors.initials: A
authors.lastname: Stepanian
authors.forename: Laure
authors.initials: L
authors.lastname: Bourguignat
authors.forename: Sabiha
authors.initials: S
authors.lastname: Hennou
authors.forename: Muriel
authors.initials: M
authors.lastname: Coupaye
authors.forename: David
authors.initials: D
authors.lastname: Hajage
authors.forename: Laurence
authors.initials: L
authors.lastname: Salomon
authors.forename: Marie-Christine
authors.initials: MC
authors.lastname: Alessi
authors.forename: Simon
authors.initials: S
authors.lastname: Msika
authors.forename: Dominique
authors.initials: D
authors.lastname: de Prost
mesh_terms: D000328:Adult; D015992:Body Mass Index; D016022:Case-Control Studies; D055252:Cell-Derived Microparticles / Q000378:metabolism*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007962:Leukocytes / Q000473:pathology; D008297:Male; D024821:Metabolic Syndrome / Q000097:blood* / Q000150:complications; D008875:Middle Aged; D009767:Obesity, Morbid / Q000097:blood* / Q000150:complications / Q000628:therapy; D010974:Platelet Aggregation; D015431:Weight Loss / Q000502:physiology*