Atractylenolide-I covalently binds to CYP11B2,selectively inhibits aldosterone synthesis, and improves hyperaldosteronism

Hyperaldosteronism is a common disease that is closely related to endocrine hypertension and other cardiovascular diseases. Cytochrome P450 11 B2(CYP11 B2), an important enzyme in aldosterone(ALD) synthesis, is a promising target for the treatment of hyperaldosteronism. However, selective inhibitors targeting CYP11 B2 are still lacking due to the high similarity with CYP11 B1. In this study,atractylenolide-I(AT-I) was found to significantly reduce the production of ALD but had no effect on cortisol synthesis, which is catalyzed by CYP11 B1. Chemical biology studies revealed that due to the presence of Ala320, AT-I is selectively bound to the catalytic pocket of CYP11 B2, and the C8/C9 double bond of AT-I can be epoxidized, which then undergoes nucleophilic addition with the sulfhydryl group of Cys450 in CYP11 B2. The covalent binding of AT-I disrupts the interaction between heme and CYP11 B2 and inactivates CYP11 B2, leading to the suppression of ALD synthesis;AT-I shows a significant therapeutic effect for improving hyperaldosteronism.