title: Bacterial DNA translocation holds increased insulin resistance and systemic inflammatory levels in morbid obese patients.
abstract: BACKGROUND
  Morbidly obese patients show several common comorbidities associated with immunological alterations such as a sustained low-level proinflammatory profile. Bacterial product translocation is frequent in inflammation-related diseases and may aggravate patients' clinical outcome.
  
  
  METHODS
  Consecutively admitted morbidly obese patients who presented indications for bariatric surgery were studied. Before surgery, patients were subjected to a modified fasting diet. Patients underwent surgery by sleeve gastrectomy or laparoscopic Roux-en-Y gastric bypass. Clinical and analytical parameters were recorded. Blood samples were collected at baseline, at the end of a 3-month modified fasting period, and 3, 6, and 12 months after surgery. Serum cytokine and endotoxin levels were evaluated by flow cytometry and ELISA, respectively. Bacterial DNA was identified in blood by broad-range PCR of prokaryote 16SrRNA gene and partial sequencing analysis.
  
  
  RESULTS
  Fifty-eight patients were included in the study. All patients showed a significantly reduced weight and body mass index at each time-point. Postoperative mortality was null. Bacterial DNA translocation rate was 32.8% (19 of 58) at baseline; 13.8% (8 of 58) after the modified fasting period; and 13.8% (8 of 58), 1.8% (1 of 58), and 5.2% (3 of 58) at 3, 6, and 12 months after surgery. Proinflammatory cytokines, serum endotoxin levels, and insulin resistance remained increased in patients with bacterial DNA despite weight loss and were individually affected by the appearance/clearance of bacterial DNA in blood. Multivariate analyses revealed bacterial DNA as an independent significant factor, explaining the systemic cytokine response and the insulin resistance levels in the studied population.
  
  
  CONCLUSIONS
  Bacterial DNA translocation holds increased insulin resistance and systemic inflammatory levels in morbidly obese patients despite significant weight loss.
authors.affiliation: Servicio de Cirugía General y Digestiva (S.O., J.L.E., P.E., M.R., F.L.), Servicio de Farmacología Clínica (P.Z.), and Servicio de Endocrinología (A.A.), Hospital General Universitario de Alicante, 03010 Alicante, Spain; CIBERehd (P.Z., J.S., R.F.), Instituto de Salud Carlos III, 28029 Madrid, Spain; and Departamento de Medicina Clínica (P.Z., J.S., R.F.), Universidad Miguel Hernández, 03550 San Juan de Alicante, Spain.
authors.forename: Sergio
authors.initials: S
authors.lastname: Ortiz
authors.forename: Pedro
authors.initials: P
authors.lastname: Zapater
authors.forename: José Luis
authors.initials: JL
authors.lastname: Estrada
authors.forename: Pablo
authors.initials: P
authors.lastname: Enriquez
authors.forename: Monica
authors.initials: M
authors.lastname: Rey
authors.forename: Angel
authors.initials: A
authors.lastname: Abad
authors.forename: José
authors.initials: J
authors.lastname: Such
authors.forename: Félix
authors.initials: F
authors.lastname: Lluis
authors.forename: Rubén
authors.initials: R
authors.lastname: Francés
mesh_terms: D000328:Adult; D018988:Bacterial Translocation; D050110:Bariatric Surgery; D015992:Body Mass Index; D016207:Cytokines / Q000097:blood; D004269:DNA, Bacterial / Q000097:blood / Q000378:metabolism*; D005260:Female; D006801:Humans; D007249:Inflammation / Q000097:blood* / Q000382:microbiology*; D007333:Insulin Resistance / Q000276:immunology; D008297:Male; D008875:Middle Aged; D009767:Obesity, Morbid / Q000097:blood* / Q000175:diagnosis / Q000601:surgery; D011184:Postoperative Period; D015431:Weight Loss
chemical_list: D016207:Cytokines; D004269:DNA, Bacterial