Subacute effects of the chlorinated flame retardant dechlorane 602 on intestinal microenvironment in mice

Yunping Li; Heidi Qunhui Xie; Yin Liu; Li Xu; Liping Zheng; Shuyuan Yu; Guomin Chen; Jiajia Ji; Shuai Jiang; Tai L Guo; Bin Zhao

doi:10.1016/j.envint.2022.107394

Subacute effects of the chlorinated flame retardant dechlorane 602 on intestinal microenvironment in mice

Environ Int. 2022 Aug:166:107394. doi: 10.1016/j.envint.2022.107394. Epub 2022 Jul 6.

Authors

Yunping Li¹, Heidi Qunhui Xie², Yin Liu³, Li Xu², Liping Zheng², Shuyuan Yu⁴, Guomin Chen⁴, Jiajia Ji⁴, Shuai Jiang⁴, Tai L Guo⁵, Bin Zhao⁶

Affiliations

¹ School of Environment, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, Zhejiang 310024, China; State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
² State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
³ School of Environment, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, Zhejiang 310024, China.
⁴ Environment and Health Department, Shenzhen Center for Disease Control and Prevention, Shenzhen, Guangdong 518055, China.
⁵ Department of Veterinary Biomedical Sciences, University of Georgia, Athens, GA 30602, USA. Electronic address: tlguo1@uga.edu.
⁶ School of Environment, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, Zhejiang 310024, China; State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China. Electronic address: binzhao@rcees.ac.cn.

PMID: 35820366
DOI: 10.1016/j.envint.2022.107394

Abstract

Background: Chlorinated flame retardant Dechlorane 602 (Dec 602) has been detected in daily food, indicating that it may pose a risk to intestinal health. The intestinal microenvironment plays an important role in intestinal health. Intestinal microbiota and metabolites are two important factors for maintaining the microenvironment. However, little is known about the effects of Dec 602 on intestinal microbiota and metabolites.

Objectives: We aimed to probe the effects of Dec 602 on the intestine by revealing the changes that Dec 602 caused to the intestinal microbiota and metabolites.

Methods: Adult female C57BL/6 mice were exposed to Dec 602 (low/high doses: 1.0/10.0 μg/kg body weight per day) orally for 7 consecutive days, and sacrificed after 7 days of recovery. The composition of colonic microbiota was measured by 16S rRNA gene sequencing, and the colonic metabolites were determined by LC-ESI-MS/MS. Finally, the effects of Dec 602 on the colon were validated by histopathological analysis.

Results: The intestinal microbiota composition was altered toward a pro-inflammatory status after exposure to Dec 602. Dec 602 exposure also up-regulated oxidative metabolites (glutathione disulfide, taurine and retinoic acid) and pro-inflammatory metabolites (prostaglandin E₂). On the other hand, antioxidative metabolites (s-adenosylmethionine and 11-cis-retinol) and anti-inflammatory metabolites (alpha-linolenic acid, eicosapentaenoic acid and docosahexaenoic acid) were down-regulated after exposure to Dec 602. Infiltration of lymphocytes in the colonic lamina propria was observed in the mice treated with Dec 602 for 7 days, and it was not recovered after another 7 days without further treatment.

Conclusion: Dec 602 interfered with the colonic microbiota and metabolome, and exhibited inflammatory features. Histopathological studies confirmed that Dec 602 exposure did induce colonic inflammation.

Keywords: Dec 602; Inflammation; Metabolites; Microbiota; Oxidative stress.