Aromatase is required for female abdominal aortic aneurysm protection

The protective effects of female gender against abdominal aortic aneurysm (AAA) formation are linked to estrogen but may be due to either systemic or local hormonal effects. Manipulation of sex hormones is a possible therapeutic target for AAA treatment. This study investigates the role of aromatase, the enzyme responsible for estrogen formation, and demonstrates that both ovarian and peripheral estrogen production by aromatase are needed for female AAA protection. Extragonadal production of estrogen by aromatase within aortic smooth muscle cells and macrophages offers a novel method to possibly deliver beneficial anti-inflammatory properties of estrogen therapy without systemic side effects.