Estrogen metabolism by cytochrome P450 1B1 modulates the hypertensive effect of angiotensin II in female mice.
To determine the role of cytochrome P450 (CYP) 1B1 in the sex difference in response to angiotensin II (Ang II)-induced hypertension, female Cyp1b1(+/+) and Cyp1b1(-/-) mice were infused with Ang II (700 ng/kg per minute) or vehicle with or without ovariectomy. In addition, mice were treated with the CYP1B1 inhibitor, 2,3',4,5'-tetramethoxystilbene (TMS; 300 μg/kg IP, every third day), and 17-β estradiol metabolites, 2-hydroxyestradiol (2-OHE), 4-OHE, or 2-methoxyestradiol (1.5 mg/kg per day IP, for 2 weeks) and systolic blood pressure (SBP) measured. Ang II increased SBP more in Cyp1b1(-/-) than in Cyp1b1(+/+) mice (119±3-171±11 versus 120±4-149±4 mm Hg; P<0.05). Ang II caused cardiovascular remodeling and endothelial dysfunction and increased vascular reactivity and oxidative stress in Cyp1b1(-/-) but not in Cyp1b1(+/+)mice. The Ang II-induced increase in SBP was enhanced by ovariectomy and TMS in Cyp1b1(+/+) but not in Cyp1b1(-/-) mice. 2-OHE did not alter Ang II-induced increase in SBP in Cyp1b1(+/+) mice but minimized it in Cyp1b1(-/-) mice, whereas 4-OHE enhanced Ang II-induced increase in SBP in Cyp1b1(+/+) mice but did not alter the increased SBP in Cyp1b1(-/-) mice. 2-OHE-derived catechol-O-methyltransferase metabolite, 2-methoxyestradiol, inhibited Ang II-induced increase in SBP in Cyp1b1(-/-) mice. Ang II increased plasma levels of 2-methoxyestradiol in Cyp1b1(+/+) but not in Cyp1b1(-/-) mice and increased activity of cardiac extracellular signal-regulated kinase 1/2, p38 mitogen-activated kinase, c-Src, and Akt in Cyp1b1(-/-) but not in Cyp1b1(+/+) mice. These data suggest that CYP1B1 protects against Ang II-induced hypertension and associated cardiovascular changes in female mice, most likely mediated by 2-methoxyestradiol-inhibiting oxidative stress and the activity of these signaling molecules.
['Jennings|Brett L|BL|', 'George|L Watson|LW|', 'Pingili|Ajeeth K|AK|', 'Khan|Nayaab S|NS|', 'Estes|Anne M|AM|', 'Fang|Xiao R|XR|', 'Gonzalez|Frank J|FJ|', 'Malik|Kafait U|KU|']
D000804:Angiotensin II D000818:Animals D001189:Aryl Hydrocarbon Hydroxylases D001794:Blood Pressure D065633:Cytochrome P-450 CYP1B1 D004958:Estradiol D005260:Female D006321:Heart D006973:Hypertension D051379:Mice D018345:Mice, Knockout D009206:Myocardium D018384:Oxidative Stress
cytochrome P450 1B1 hypertension ovariectomy 2-methoxyestradiol oxidative stress