Evaluation of estrogenic compounds in botanical dietary supplements using mass spectrometry.

摘要

During menopause, women often experience vasomotor symptoms and other sequelae due to low levels of estrogens. Hormone replacement therapy (HRT) is used by many women for the management of menopausal symptoms. However, long-term estrogen replacement therapy is associated with an increased risk of developing breast and endometrial cancers and other side effects. Botanical dietary supplements are being used by some women as potential alternatives to HRT, but these products are in need of careful standardization and evaluation for safety and efficacy. Therefore, mass spectrometry based assays were developed to screen and evaluate botanical dietary supplements for estrogen content.; As a high throughput alternative to conventional assays, ultrafiltration LC-MS assay was used for the screening of botanical dietary supplements for estrogenic compounds. In this assay, the botanical extracts were incubated with ER-alpha or ER-beta. The unbound compounds were separated from ER and the ER-ligand complex by ultrafiltration, and then any bound ligands were released from ER-alpha or ER-beta and analyzed using LC-MS. Ultrafiltration LC-MS is faster and less labor intensive than conventional pharmacogonosy approaches and is unique by providing mass spectrometric structural information. In addition, the relative binding affinities of multiple ligands in a mixture can be ranked by using this assay.; Botanical dietary supplements being used by women for the relief of menopausal symptoms, such as red clover, hops, black cohosh, chaste-berry, and maca, were screened for estrogens. Estrogenic flavonoids were identified in red clover and hops, none were detected in significant levels in black cohosh, and non-estrogenic fatty acids were observed as ligands for estrogen receptors in chaste-berry and maca.; In addition, an LGMS method was developed and validated in support of a Phase 1 clinical study of red clover in women. Genistein, daidzein, biochanin A, and formononetin, were measured in serum and urine. The pharmacokinetics parameters were determined from the time-concentration curves for the serum samples.; In conclusion, new mass spectrometry based assays was developed and used to enhance the productivity of studies of the safety and efficacy of botanical dietary supplements as alternatives to HRT.