Ultrafine Particles Altered Gut Microbial Population and Metabolic Profiles in a Sex-Specific Manner in an Obese Mouse Model

Authors: YANG, KUNDI - Miami University - Ohio; XU, MENGYANG - Miami University - Ohio; CAO, JINGYI - Miami University - Ohio; QI, ZHU - Miami University - Ohio; RAHMAN, MONICA - Miami University - Ohio; HOLMEN, BRITT - University Of Vermont; Fukagawa, Naomi; ZHU, JIANGJIANG - The Ohio State University

Submitted to: Nature Scientific Reports
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/3/2021
Publication Date: 3/25/2021
Citation: Yang, K., Xu, M., Cao, J., Qi, Z., Rahman, M., Holmen, B.A., Fukagawa, N.K., Zhu, J. 2021. Ultrafine particles altered gut microbial population and metabolic profiles in a sex-specific manner in an obese mouse model. Nature Scientific Reports. 11. Article 6906. https://doi.org/10.1038/s41598-021-85784-4.
DOI: https://doi.org/10.1038/s41598-021-85784-4

Interpretive Summary: Emerging evidence has highlighted the need for scientists, physicians and other healthcare professionals, and policy-makers to understand the potential adverse effects of air pollutants, such as ultrafine particles (UFPs), on overall human health through the complex interations with the human gut microbiota. We discovered that UFP exposure is associated with changes in the relative abundance of the microbes and their metabolites in the host gut. Furthermore, plasma metabolites from the obese mice were differentially affected by the fuel type used to generate the UFPs (B0 vs. B20). Bacterial cellular oxidative stress and their metabolic signatures, such as the decreased concentration of nucleotides and lipids and increased concentrations of carbohydrate, energy and vitamin metabolites were detected. Sex-specific differences in the gut microbial population and their metabolic profiles in response to UFP exposure were also observed. Future studies should include varying the UFP dose to recapitulate the range of human exposure and comparing acute versus chronic exposure to elucidate the effects of different durations of PM exposure on the gut microbiome.

Technical Abstract: Emerging evidence has highlighted the need for scientists, physicians and other healthcare professionals, and policy-makers to understand the potential adverse effects of air pollutants, such as ultrafine particles (UFPs), on overall human health through the complex interactions with the human gut microbiota. The objective of the study was to determine the modulating effects of gastrointestinal (GI) UFPs exposure on gut microbial composition and functions that may lead to a systematic evaluation of the impact of UFPs on host health. Due to the rising use of biodiesel fuel in our society, and the paucity of information on the health effects of biodiesel exhaust particles, UFPs generated from the combustion of both petrodiesel (B0) and a petrodiesel/biodiesel blend (80:20 v/v, B20) in a representative light-duty diesel engine were used in this study. An in vivo murine model of obesity in both sexes was used to investigate the gut microbial population and diversity changes during UFP exposure over ten days. Multi-omics approaches, including targeted metabolomics and microbiome analysis, were applied to evaluate the UFP-related effects on the gut microbial population and its function. We discovered that UFP exposure is associated with changes in the relative abundance of the microbes and their metabolites in the host gut. Furthermore, plasma metabolites from the obese mice were differentially affected by the fuel type used to generate the UFPs (B0 vs. B20). Bacterial cellular oxidative stress and their metabolic signatures, such as the decreased concentration of nucleotides and lipids and increased concentrations of carbohydrate, energy and vitamin metabolites were detected. Sex-specific differences in the gut microbial population and their metabolic profiles in response to UFP exposure were also observed. Future studies should include varying the UFP dose to recapitulate the range of human exposure and comparing acute versus chronic exposure to elucidate the effects of different durations of PM exposure on the gut microbiome.