Table 5 Experimental binding/agonistic effects of PFAS to PPARγ, PPARβ/δ and PPARα (see also Involvement of PPARs section, Results)
From: Consideration of pathways for immunotoxicity of per- and polyfluoroalkyl substances (PFAS)
Compound and activity | Test system (organism) | Reference |
|---|---|---|
PPARγ | ||
 PFBS exposure – causes elevated expression of PPARγ (b) | In vitro (HepG2) | [224] |
 PFOA – can activate PPARγ (e) | In vivo (mussel) | [225] |
 PFOA – agonistic activity towards PPARγ (f) | In vitro (HEK 293) | [226] |
 PFCAs – C8 to C14 showed an agonistic activity towards PPARγ, in HPA cells the activity increased from C8 to C11 and then fluctuated, in 3 T3-L1 the activity increased from C8 to C13 and then slightly fluctuated (g) | In vitro (HPA-s; HEK 293; 3 T3-L1) | [147] |
 PFCAs – bind to PPARγ, binding affinity increased from C4 to C11 and then decreased slightly from C12 to C18 (c) | In vitro (HepG2) | [148] |
 PFSAs – binding to PPARγ, binding affinity is stronger compared to PFCAs with the same carbon chain-length (c) | In vitro (HepG2) | [148] |
 PFOA and PFOS – bind to PPARγ, PFOA shows a higher binding affinity compared to PFOS (d) | In vitro (buffer solution) | [227] |
 PFOS binds to PPARγ – agonistic activity (a) | In vitro (3 T3-L1; HEK 293) | [122] |
 6:2 Cl-PFAES binds to PPARγ - agonistic activity (a) | In vitro (3 T3-L1; HEK 293) | [122] |
 8:2 Cl-PFAES binds to PPARγ - agonistic activity (a) | In vitro (3 T3-L1; HEK 293) | [122] |
 HFPO-TA and HFPO-DA – agonistic activity towards PPARγ (f) | In vitro (HEK 293) | [226] |
 PFAAs - containing carbon chain-length from C6 to C12 may alter the PPARγ activity; sulfonic acid groups showed a higher affinity to bind to PPARγ compared to carboxylic acids with the same carbon chain length (h) | In silico (Molecular dynamic calculations) | [228] |
 DONA – shows the ability to activate PPARγ (h) | In silico (Molecular dynamic calculations) | [228] |
PPARβ/δ | ||
 PFBA, PFHxS and PFOS – binds to PPARβ/δ (d) | In vitro (buffer solution) | [227] |
 PFOS binds to PPARβ/δ – agonistic activity (a) | In vitro (3 T3-L1; HEK 293) | [122] |
 6:2 and 8:2 Cl-PFAES bind to PPARβ/δ - agonistic activity (a) | In vitro (3 T3-L1; HEK 293) | [122] |
PPARα | ||
 HFPO-DA – PPARα (i) activation | Maternal and foetal liver tissue (rat) | [229] |
 PFBS – PPARα (b) activation | In vitro (HepG2) | [224] |
 HFPO-DA – PPARα (j) activation | New-born pup liver tissue (rat) | [121] |
 PFHxA and PFNA – strong binding to PPARα (d) | In vitro (buffer solution) | [227] |
 PFOS – agonistic activity towards PPARα (a) | In vitro (3 T3-L1 cells) | [122], |
 6:2 Cl-PFESA – strong binding to PPARα (k) | In vitro (3 T3-L1 cells) | [230] |
 PFBA, PFHxA, PFOA, PFHxS and PFOS – PPARα (l) activation | In vitro (HepG2) | [231] |
 PFOA – PPARα (m) activation | In vitro (MCF-10A) | [232] |