Organophosphorus pesticide chlorpyrifos intake promotes obesity and insulin resistance through impacting gut and gut microbiota

Microbiome. 2019 Feb 11;7(1):19. doi: 10.1186/s40168-019-0635-4.


Background: Disruption of the gut microbiota homeostasis may induce low-grade inflammation leading to obesity-associated diseases. A major protective mechanism is to use the multi-layered mucus structures to keep a safe distance between gut epithelial cells and microbiota. To investigate whether pesticides would induce insulin resistance/obesity through interfering with mucus-bacterial interactions, we conducted a study to determine how long-term exposure to chlorpyrifos affected C57Bl/6 and CD-1 (ICR) mice fed high- or normal-fat diets. To further investigate the effects of chlorpyrifos-altered microbiota, antibiotic treatment and microbiota transplantation experiments were conducted.

Results: The results showed that chlorpyrifos caused broken integrity of the gut barrier, leading to increased lipopolysaccharide entry into the body and finally low-grade inflammation, while genetic background and diet pattern have limited influence on the chlorpyrifos-induced results. Moreover, the mice given chlorpyrifos-altered microbiota had gained more fat and lower insulin sensitivity.

Conclusions: Our results suggest that widespread use of pesticides may contribute to the worldwide epidemic of inflammation-related diseases.

Keywords: Chlorpyrifos; Gut microbiota; Insulin resistance; Lipopolysaccharide; Obesity; Organophosphorus pesticide.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Body Weight / drug effects
  • Chlorpyrifos / toxicity*
  • Dysbiosis / chemically induced*
  • Gastrointestinal Microbiome / drug effects*
  • Inflammation / chemically induced
  • Insecticides / toxicity*
  • Insulin Resistance / physiology*
  • Intestinal Mucosa / microbiology*
  • Intestinal Mucosa / pathology*
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mice, Inbred ICR
  • Obesity / chemically induced*
  • Tight Junctions / drug effects
  • Tight Junctions / pathology
  • Weight Gain / drug effects


  • Insecticides
  • Chlorpyrifos