title: Acute effect of roux-en-y gastric bypass on whole-body insulin sensitivity: a study with the euglycemic-hyperinsulinemic clamp.
abstract: BACKGROUND
  Insulin resistance ameliorates after bariatric surgery, yet there is still a need for data on the acute effect of Roux-en-Y gastric bypass (RYGBP) on insulin sensitivity.
  
  
  OBJECTIVE
  The objective of the study was to describe the acute effect of RYGBP on insulin sensitivity, measured by both the euglycemic-hyperinsulinemic clamp and homeostasis model assessment insulin resistance index (HOMA-IR).
  
  
  METHODS
  Evaluations were conducted before and 1 month after RYGBP at State University of Campinas (São Paulo, Brazil).
  
  
  METHODS
  Patients included 19 premenopausal women with metabolic syndrome aged 35.3 (6.7) yr, body mass index 45.50 (3.74) kg/m2 [mean (sd)]. Six had mild type 2 diabetes, seven impaired glucose tolerance, and six normal glucose tolerance.
  
  
  METHODS
  The volunteers underwent RYGBP either alone or combined with omentectomy. Euglycemic-hyperinsulinemic clamp, HOMA-IR, nonesterified fatty acids, leptin, ultrasensitive C-reactive protein, adiponectin, and IL-6 were assessed at baseline and 4.5 (0.9) wk postoperatively.
  
  
  RESULTS
  Fasting glucose decreased [99.2 (13.1) to 83.6 (8.1) mg/dl, P<0.01] along with a reduction in fasting insulin [30.4 (17.0) to 11.4 (6.3) mU/liter, P<0.01]. M value did not improve postoperatively [25.82 (6.30) to 22.02 (6.05) micromol/kgFFM.min] despite of a decrease in body weight [114.8 (14.5) to 102.3 (14.5) kg, P<0.001]. This finding was discordant to the observation of an improvement in HOMA-IR [3.85 (2.10) to 1.42 (0.76), P<0.01]. Nonesterified fatty acids increased. Leptin and C-reactive protein decreased. IL-6 and adiponectin remained unchanged.
  
  
  CONCLUSIONS
  A month after RYGBP, fasting glucose metabolism improves independent of a change in peripheral insulin sensitivity.
authors.affiliation: LIMED/Gastrocentro, R. Carlos Chagas, Department of Surgery, 420, Cidade Universitária, State University of Campinas (UNICAMP), Campinas, São Paulo, 13081-970, Brazil. endo.marcelolima@hotmail.com
authors.forename: Marcelo M O
authors.initials: MM
authors.lastname: Lima
authors.forename: José C
authors.initials: JC
authors.lastname: Pareja
authors.forename: Sarah M
authors.initials: SM
authors.lastname: Alegre
authors.forename: Sylka R
authors.initials: SR
authors.lastname: Geloneze
authors.forename: Steven E
authors.initials: SE
authors.lastname: Kahn
authors.forename: Brenno D
authors.initials: BD
authors.lastname: Astiarraga
authors.forename: Elinton A
authors.initials: EA
authors.lastname: Chaim
authors.forename: Bruno
authors.initials: B
authors.lastname: Geloneze
mesh_terms: D052242:Adiponectin / Q000097:blood; D000328:Adult; D001786:Blood Glucose / Q000378:metabolism; D015992:Body Mass Index; D002097:C-Reactive Protein / Q000378:metabolism; D003924:Diabetes Mellitus, Type 2 / Q000378:metabolism / Q000601:surgery; D004797:Enzyme-Linked Immunosorbent Assay; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005260:Female; D015390:Gastric Bypass; D015309:Glucose Clamp Technique; D006801:Humans; D007333:Insulin Resistance; D015850:Interleukin-6 / Q000097:blood; D020738:Leptin / Q000097:blood; D024821:Metabolic Syndrome / Q000378:metabolism / Q000601:surgery*; D009767:Obesity, Morbid / Q000378:metabolism / Q000601:surgery*; D018709:Statistics, Nonparametric; D016896:Treatment Outcome
chemical_list: D052242:Adiponectin; D001786:Blood Glucose; D005230:Fatty Acids, Nonesterified; D015850:Interleukin-6; D020738:Leptin; D002097:C-Reactive Protein