Title
Systemic PFOS and PFOA exposure and disturbed lipid homeostasis in humans: what do we know and what not?
Author
Fragki, S.S.
Dirven, H.
Fletcher, T.
Grasl-Kraupp, B.
Guetzkow, K.B.
Hoogenboom, R.
Kersten, S.
Lindeman, B.
Louisse, J.
Peijnenburg, A.
Aldert H.,
Piersma, A.H.
Princen, H.M.G.
Uhl, M.
Westerhout, J.
Zeilmaker, M.J.
Luijten, M.
Publication year
2021
Abstract
Associations between per- and polyfluoroalkyl substances (PFASs) and increased blood lipids have been repeatedly observed in humans, but a causal relation has been debated. Rodent studies show reverse effects, i.e. decreased blood cholesterol and triglycerides, occurring however at PFAS serum levels at least 100-fold higher than those in humans. This paper aims to present the main issues regarding the modulation of lipid homeostasis by the two most common PFASs, PFOS and PFOA, with emphasis on the underlying mechanisms relevant for humans. Overall, the apparent contrast between human and animal data may be an artifact of dose, with different molecular pathways coming into play upon exposure to PFASs at very low versus high levels. Altogether, the interpretation of existing rodent data on PFOS/PFOA-induced lipid perturbations with respect to the human situation is complex. From a mechanistic perspective, research on human liver cells shows that PFOS/PFOA activate the PPARa pathway, whereas studies on the involvement of other nuclear receptors, like PXR, are less conclusive. Other data indicate that suppression of the nuclear receptor HNF4a signaling pathway, as well as perturbations of bile acid metabolism and transport might be important cellular events that require further investigation. Future studies with human-relevant test systems would help to obtain more insight into the mechanistic pathways pertinent for humans. These studies shall be designed with a careful consideration of appropriate dosing and toxicokinetics, so as to enable biologically plausible quantitative extrapolations. Such research will increase the understanding of possible perturbed lipid homeostasis related to PFOS/ PFOA exposure and the potential implications for human health.
Subject
PFOS
PFOA
HBM4EU
Serum levels
Lipid perturbation; cholesterol
LDL
Triglycerides
Lipoprotein metabolism
Hepatocytes
To reference this document use:
http://resolver.tudelft.nl/uuid:4d0037d9-2612-4860-a5f3-fa6a42de347a
DOI
https://doi.org/10.1080/10408444.2021.1888073
TNO identifier
955713
Source
Critical Reviews in Toxicology, 5 (5), 141-164
Document type
article