Gut microbiota partially mediates the effects of fine particulate matter on type 2 diabetes: Evidence from a population-based epidemiological study

Environ Int. 2019 Sep;130:104882. doi: 10.1016/j.envint.2019.05.076. Epub 2019 Jun 12.

Abstract

Background: Experimental studies have indicated that alterations in the gut microbiota might play a role in the pathway of diabetes induction resulting from particulate matter pollution with aerodynamic diameters < 2.5 μm (PM2.5). However, few human studies have examined such experimental findings. Here, we examine the mediating effects of gut microbial dysbiosis on the associations between PM2.5 and particulate matter pollution with aerodynamic diameters < 1 μm (PM1) on diabetes using the Guangdong Gut Microbiome Project (GGMP) dataset.

Methods: A multistage cluster sampling method was employed to recruit adult participants from communities in Guangdong. Each participant was interviewed using a questionnaire, fasting blood and stool samples were collected, and the exposure to air pollutants was assessed using a spatiotemporal land-use regression model. The mediation analysis was conducted to estimate the associations among air pollutants, gut microbiota diversity and diabetes.

Results: Both PM2.5 and PM1 were positively associated with the risks of impaired fasting glucose (IFG) or type 2 diabetes and negatively associated with alpha diversity indices of the gut microbiota. The mediation analyses indicated that the associations of PM2.5 and PM1 with the risk of type 2 diabetes were partially mediated by the decrease in gut microbiota diversity. Moreover, we found that 79 (PM2.5 on IFG), 84 (PM2.5 on type 2 diabetes), 83 (PM1 on IFG) and 89 (PM1 on type 2 diabetes) bacterial taxa could partially mediate the associations of PM2.5 and PM1 with IFG and type 2 diabetes, respectively. The relative abundance of most Firmicutes, Proteobacteria and Verrucomicrobia bacteria were negatively associated with particulate matter (PM) concentrations and the risks of diabetes.

Conclusions: Long-term exposure to PM may increase the risk of diabetes, and alterations in the gut microbiota partially explained these associations.

Keywords: Ambient particles; Diabetes; Gut microbiota; PM(1); PM(2.5).

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Air Pollutants / adverse effects*
  • Blood Glucose / analysis
  • Diabetes Mellitus, Type 2 / blood
  • Diabetes Mellitus, Type 2 / epidemiology*
  • Diabetes Mellitus, Type 2 / microbiology
  • Environmental Exposure / adverse effects
  • Feces / microbiology
  • Female
  • Gastrointestinal Microbiome*
  • Humans
  • Male
  • Middle Aged
  • Particulate Matter / adverse effects*

Substances

  • Air Pollutants
  • Blood Glucose
  • Particulate Matter