title: Pyrethroid Pesticides as Endocrine Disruptors: Molecular Mechanisms in Vertebrates with a Focus on Fishes.
abstract: Pyrethroids are now the fourth most used group of insecticides worldwide. Employed in agriculture and in urban areas, they are detected in waterways at concentrations that are lethally and sublethally toxic to aquatic organisms. Highly lipophilic, pyrethroids accumulate in sediments and bioaccumulate in fishes. Additionally, these compounds are demonstrated to act as endocrine disrupting compounds (or EDCs) in mammals and fishes, and therefore interfere with endocrine signaling by blocking, mimicking, or synergizing endogenous hormones through direct receptor interactions, and indirectly via upstream signaling pathways. Pyrethroid metabolites have greater endocrine activity than their parent structures, and this activity is dependent on the enantiomer present, as some pyrethroids are chiral. Many EDCs studied thus far in fish have known estrogenic or antiestrogenic effects, and as such cause the inappropriate or altered expression of genes or proteins (i.e., Vtg-vitellogenin, Chg-choriogenin), often leading to physiological or reproductive effects. Additionally, these compounds can also interfere with other endocrine pathways and immune response. This review highlights studies that focus on the mechanisms of pyrethroid biotransformation and endocrine toxicity to fishes across a broad range of different pyrethroid types, and integrates literature on the in vitro and mammalian responses that inform these mechanisms.
authors.affiliation: Biology & Marine Biology, University of North Carolina at Wilmington , 601 South College Road, Wilmington, North Carolina, 28403, United States.
authors.forename: Susanne M
authors.initials: SM
authors.lastname: Brander
authors.affiliation: Biology & Marine Biology, University of North Carolina at Wilmington , 601 South College Road, Wilmington, North Carolina, 28403, United States.
authors.forename: Molly K
authors.initials: MK
authors.lastname: Gabler
authors.affiliation: Biology & Marine Biology, University of North Carolina at Wilmington , 601 South College Road, Wilmington, North Carolina, 28403, United States.
authors.forename: Nicholas L
authors.initials: NL
authors.lastname: Fowler
authors.affiliation: Anatomy, Physiology & Cell Biology, School of Veterinary Medicine, University of California at Davis , One Shields Avenue, Davis, California 95616, United States.
authors.forename: Richard E
authors.initials: RE
authors.lastname: Connon
authors.affiliation: Environmental Sciences, College of Natural and Agricultural Sciences, University of California at Riverside , 900 University Avenue, Riverside, California 92521, United States.
authors.forename: Daniel
authors.initials: D
authors.lastname: Schlenk
mesh_terms: D000818:Animals; D052244:Endocrine Disruptors; D004967:Estrogens / Q000378:metabolism*; D005399:Fishes / Q000378:metabolism; D010575:Pesticides; D011722:Pyrethrins
chemical_list: D052244:Endocrine Disruptors; D004967:Estrogens; D010575:Pesticides; D011722:Pyrethrins