Aromatase Inhibitors

I couldn't tell from Sarah Everts' article whether the natural chemical chrysin was as bad a signal blocker as the unnatural chemicals she mentioned (bisphenol A, methyl parathion, pentachlorophenol, and DDT) (C&EN, June 11, page 14). On the other hand, chrysin was one of the most potent antiaromatase compounds in one study. That could be as important to senior citizens as signal disruption is to nitrogen-fixing nodules.

Aging men often have excess aromatase enzyme activity, and too much of their testosterone is converted to estrogen. In mice injected with diazepam (Valium), chrysin, or placebo, chrysin produced antianxiety effects comparable to diazepam, but without sedation and muscle relaxation. For women, aromatase inhibitors are used to treat estrogen-dependent breast cancers. Of 11 flavonoids in one study, chrysin, the most potent aromatase inhibitor, was shown to be similar in potency and effectiveness to the drug aminoglutethimide

Your readers might be interested in the free phytochemcial database online at USDA, wherein you can query for some reported biological activities of thousands of chemicals like chrysin (www.pl.barc.usda.gov/usda_chem/achem_home.cfm).

James A. Duke
Fulton, Md.