RT Journal Article SR Electronic T1 Cytochrome P450 Eicosanoids are Activators of Peroxisome Proliferator-Activated Receptor α JF Drug Metabolism and Disposition JO Drug Metab Dispos FD American Society for Pharmacology and Experimental Therapeutics SP 1126 OP 1134 DO 10.1124/dmd.106.013839 VO 35 IS 7 A1 Valerie Y. Ng A1 Yong Huang A1 L. Manmohan Reddy A1 John R. Falck A1 Emil T. Lin A1 Deanna L. Kroetz YR 2007 UL http://dmd.aspetjournals.org/content/35/7/1126.abstract AB Cytochrome P450 (P450) eicosanoids regulate vascular tone, renal tubular transport, cellular proliferation, and inflammation. Both the CYP4A ω-hydroxylases, which catalyze 20-hydroxyeicosatetraenoic acid (20-HETE) formation, and soluble epoxide hydrolase (sEH), which catalyzes epoxyeicosatrienoic acid (EET) degradation to the dihydroxyeicosatrienoic acids (DHETs), are induced upon activation of peroxisome proliferator-activated receptor α (PPARα) by fatty acids and fibrates. In contrast, the CYP2C epoxygenases, which are responsible for EET formation, are repressed after fibrate treatment. We show here that P450 eicosanoids can bind to and activate PPARα and result in the modulation of PPARα target gene expression. In transactivation assays, 14,15-DHET, 11,2-EET, and 20-HETE were potent activators of PPARα. Gel shift assays showed that EETs, DHETs, and 20-HETE induced PPARα-specific binding to its cognate response element. Expression of apolipoprotein A-I was decreased 70% by 20-HETE, whereas apolipoprotein A-II expression was increased up to 3-fold by 11,12-EET, 14,15-DHET, and 20-HETE. In addition, P450 eicosanoids induced CYP4A1, sEH, and CYP2C11 expression, suggesting that they can regulate their own levels. Given that P450 eicosanoids have multiple cardiovascular effects, pharmacological modulation of their formation and/or degradation may yield therapeutic benefits. The American Society for Pharmacology and Experimental Therapeutics