Regulating the absorption and excretion of perfluorooctane sulfonate and its alternatives through influencing enterohepatic circulation

Yong Wen; Albert Juhasz; Xinyi Cui

doi:10.1016/j.scitotenv.2024.173161

Regulating the absorption and excretion of perfluorooctane sulfonate and its alternatives through influencing enterohepatic circulation

Sci Total Environ. 2024 May 10:933:173161. doi: 10.1016/j.scitotenv.2024.173161. Online ahead of print.

Authors

Yong Wen¹, Albert Juhasz², Xinyi Cui³

Affiliations

¹ State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China.
² Future Industries Institute, University of South Australia, Mawson Lakes, South Australia 5095, Australia.
³ State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China. Electronic address: lizzycui@nju.edu.cn.

PMID: 38735313
DOI: 10.1016/j.scitotenv.2024.173161

Abstract

Enterohepatic circulation has been reported to play a significant role in the bioaccumulation of PFASs. In this study, the tissue distribution and excretion of PFOS and its alternatives, namely 6:2 and 8:2 fluorotelomer sulfonic acid (FTSA) was investigated using a mouse assay with a focus on role of enterohepatic circulation. Liver was the primarily accumulating organ for PFOS and 8:2 FTSA (33.4 % and 25.8 % of total doses absorbed after 14 days), whereas 65 % of 6:2 FTSA was excreted via urine within 24 h. Peak levels of 8:2 FTSA and PFOS were found in the gallbladder, implying the important role of enterohepatic circulation in PFASs reabsorption. The role of enterohepatic circulation was further evaluated through co-exposure of 8:2 FTSA and PFOS with medicines (namely metformin (MET) and ursodeoxycholic acid (UDCA)). MET reduced accumulation of 8:2 FTSA and PFOS in the liver by 68.6 % and 65.8 %, through down-regulation of bile acid transporter (Asbt) and enhancement of fecal excretion. Conversely, UDCA raised their concentrations by 21.9 % and 34.6 % compared to that exposed solely to PFASs. A strong positive correlation was identified between PFASs serum levels and Asbt expression. This study illuminated PFAS bioaccumulation mechanisms and suggested potential strategies to mitigate the exposure risks.

Keywords: Bile acid transporter; Distribution; Enterohepatic circulation; Fluorotelomer sulfonic acid; Metformin.