Selective inhibition of CYP17A1 17,20-lyase is critical for treating hyperandrogenic disorders without the cortisol-depleting side effects of non-selective drugs like abiraterone. We evaluated tanshinones from Salvia miltiorrhiza as potential selective inhibitors using biochemical assays and computational modeling. Dihydrotanshinone (DT) emerged as the superior candidate; at 10 µM, it inhibited 17,20-lyase activity by 56.6% while preserving >93% of 17α-hydroxylase activity. This yields a selectivity index of 8.67, drastically outperforming abiraterone (0.73). Furthermore, DT displayed minimal off-target inhibition of CYP21A2 (14.9%) compared to abiraterone (29.8%). Molecular modeling suggests DT's efficacy arises from a unique, functionally disruptive binding pose rather than superior thermodynamic affinity. Consequently, DT is validated as a potent natural product lead. Its dual selectivity over 17α-hydroxylase and CYP21A2 establishes the tanshinone scaffold as a promising candidate for developing safer therapies that suppress androgens while sparing cortisol biosynthesis.
Li et al. (Wed,) studied this question.