title: Acute arsenic treatment alters arachidonic acid and its associated metabolite levels in the brain of C57Bl/6 mice.
abstract: The toxic effects of arsenic on the whole brain, as well as the discrete regions, has been previously reported for mice. We investigated the effects of acute arsenite (As(III)) on brain levels of arachidonic acid (AA) and its associated metabolites generated through cytochrome P450 (CYP), cyclooxygenase (COX), and lipoxygenase (LOX) pathways. Our results demonstrated that acute As(III) treatment (12.5 mg·(kg body mass)(-1)) decreases cytosolic phospholipase A2 (cPLA2) with a subsequent decrease in its catalytic activity and brain AA levels. In addition, As(III) differentially altered CYP epoxygenases and CYP ω-hydroxylases, but it did not affect brain Ephx2 mRNA or sEH catalytic activity levels. As(III)-mediated effects on Cyps caused an increase in brain 5,6-epoxyeicosatrienoic acid (5,6-EET) and 16/17-hydroxyeicosatetreinoic acid (16/17-HETE) levels, and a decrease in 18- and 20-HETE levels. Furthermore, As(III) increased cyclooxygenase-2 (COX-2) mRNA while decreasing prostaglandins F2α (PGF2α) and PGJ2. As(III) also increased brain 5-lipoxygenase (5-LOX) and 15-LOX mRNA, but decreased 12-LOX mRNA. These changes in LOX mRNA were associated with a decrease in 8/12-HETE levels only. In conclusion, this is the first demonstration that As(III) decreases AA levels coinciding with alterations to EET, HETE, and PG levels, which affects brain development and neurochemistry.
authors: Faculty of Pharmacy and Pharmaceutical Sciences, 2142J Katz Group-Rexall Centre for Pharmacy and Health Research, University of Alberta, Edmonton, AB T6G 2E1, Canada.
authors: Anwar
authors: A
authors: Anwar-Mohamed
authors: Osama H
authors: OH
authors: Elshenawy
authors: Ahmed A
authors: AA
authors: El-Sherbeni
authors: Mohamed
authors: M
authors: Abdelrady
authors: Ayman O S
authors: AO
authors: El-Kadi
mesh_terms: D000818:Animals; D016718:Arachidonic Acid / Q000378:metabolism*; D018053:Arsenites / Q000633:toxicity*; D001921:Brain / Q000187:drug effects* / Q000378:metabolism; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D015777:Eicosanoids / Q000378:metabolism; D004785:Environmental Pollutants / Q000633:toxicity*; D004851:Epoxide Hydrolases / Q000378:metabolism; D058945:Lipoxygenases / Q000378:metabolism; D008297:Male; D008810:Mice, Inbred C57BL; D011451:Prostaglandin-Endoperoxide Synthases / Q000378:metabolism; D017670:Sodium Compounds / Q000633:toxicity*
chemical_list: D018053:Arsenites; D015777:Eicosanoids; D004785:Environmental Pollutants; D017670:Sodium Compounds; D016718:Arachidonic Acid; C017947:sodium arsenite; D003577:Cytochrome P-450 Enzyme System; D058945:Lipoxygenases; D011451:Prostaglandin-Endoperoxide Synthases; D004851:Epoxide Hydrolases; C518648:Ephx2 protein, mouse
keywords: COX; CYP; EET; EETs; HETE; HETEs; LOX; PG; metals; métaux; sEH