Pilot study: alterations of intestinal microbiota in obese humans are not associated with colonic inflammation or disturbances of barrier function

Aliment Pharmacol Ther. 2010 Dec;32(11-12):1307-14. doi: 10.1111/j.1365-2036.2010.04475.x. Epub 2010 Sep 29.


Background: Obesity is associated with low-grade inflammation contributing to insulin-resistance. Gut barrier alterations, described in animal models of obesity, probably favour inflammation. This has not been hitherto described in obese humans.

Aim: To evaluate gut permeability in asymptomatic obese and its association with plasma (C-reactive protein (CRP), arachidonate/eicosapentaenoate ratio) and faecal (calprotectin and leptin) markers of inflammation and microbiota alterations.

Methods: A total of 13 obese (age: 33.9 ± 11.5 years; BMI: 35.9 ± 5.0 kg/m²) and 11 control subjects (age: 30.3 ± 8.1 years; BMI: 23.5 ± 2.4 kg/m²) were recruited. Gut permeability was assessed by the lactulose-mannitol-sucralose test, plasma fatty acids by gas chromatography, faecal calprotectin and leptin by Elisa and faecal microbiota by G+C profiling.

Results: C-reactive protein was increased in the obese subjects (P = 0.01), but neither the plasma arachidonate/eicosapentaenoate ratio, the faecal levels of calprotectin and leptin, nor the gut permeability were altered. The faecal microbiota was altered in the obese (P = 0.0002), with predominance of bacterial populations having a lower G+C content and decreased concentrations of high G+C populations.

Conclusions: Asymptomatic obese individuals with systemic low-grade inflammation do not have evidence of colonic inflammation or gut barrier alteration; however, the biodiversity of their intestinal microbiota is affected.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Biomarkers / analysis
  • C-Reactive Protein / analysis
  • Case-Control Studies
  • Colon / microbiology*
  • Feces / microbiology*
  • Female
  • Humans
  • Inflammation / microbiology*
  • Intestinal Absorption / physiology
  • Leptin / analysis
  • Leukocyte L1 Antigen Complex / analysis
  • Male
  • Middle Aged
  • Obesity / complications*
  • Obesity / microbiology
  • Permeability
  • Pilot Projects
  • Statistics as Topic
  • Young Adult


  • Biomarkers
  • Leptin
  • Leukocyte L1 Antigen Complex
  • C-Reactive Protein