Ambient and Traffic-Related Air Pollution Exposures as Novel Risk Factors for Metabolic Dysfunction and Type 2 Diabetes
Purpose of Review
Diabetes mellitus is a top contributor to the global burden of mortality and disability in adults. There has also been a slow but steady rise in prediabetes and type 2 diabetes in youth. The current review summarizes recent findings regarding the impact of increased exposure to air pollutants on the type 2 diabetes epidemic.
Human and animal studies provide strong evidence that exposures to ambient and traffic-related air pollutants such as particulate matter (PM), nitrogen dioxide (NO2), and nitrogen oxides (NOx) play an important role in metabolic dysfunction and type 2 diabetes etiology. This work is supported by recent findings that have observed similar effect sizes for increased exposure to air pollutants on clinical measures of risk for type 2 diabetes in children and adults. Further, studies indicate that these effects may be more pronounced among individuals with existing risk factors, including obesity and prediabetes.
Current epidemiological evidence suggests that increased air pollution exposure contributes to alterations in insulin signaling, glucose metabolism, and beta (β)-cell function. Future work is needed to identify the specific detrimental pollutants that alter glucose metabolism. Additionally, advanced tools and new areas of investigation present unique opportunities to study the underlying mechanisms, including intermediate pathways, that link increased air pollution exposure with type 2 diabetes onset.
KeywordsAir pollution Type 2 diabetes Insulin resistance Beta-cell function
Southern California Environmental Health Sciences Center grant (5P30ES007048) funded by the National Institute of Environmental Health Sciences
National Institute of Environmental Health Sciences (5P01ES011627)
Southern California Children's Environmental Health Center grant funded by National Institute of Environmental Health Sciences (5P01ES022845-03) and United States Environmental Protection Agency (RD83544101)
National Institute of Environmental Health Sciences (K99ES027853)
National Institute of Environmental Health Sciences (K99ES027870)
National Institute of Environmental Health Sciences (T32ES013678)
National Institute of Environmental Health Sciences, National Institute on Minority Health and Health Disparities (P50ES026086)
Compliance with Ethical Standards
Conflict of Interest
Tanya L. Alderete, Zhanghua Chen, Claudia Toledo-Corral, Zuelma A. Contreras, and Jennifer S. Kim report grants from NIH outside the submitted work.
Rima Habre, Leda Chatzi, and Frank D. Gilliland declare no conflicts of interest.
Theresa Bastain reports grants from NIH, during the conduct of the study.
Carrie V. Breton reports grants from NIH, outside the submitted work.
Human and Animal Rights and Informed Consent
This article does not contain any studies with human or animal subjects performed by any of the authors.
Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance
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