Topic: Natural Products / Environmental
Podium Presentation in Room 1 on Thursday at 9:00 (Chair: Richard Van Breemen / Ruben Luo)
Authors: Alan Wong, Richard B. van Breemen
INTRODUCTION: Botanical natural products can act as both agonists and antagonists of estrogen receptors. Modulations to this signaling pathway are associated with aging-associated diseases and can potentially modulate endogenous estrogen biosynthesis and metabolism. Botanical dietary supplements are popular alternatives to conventional treatment for postmenopausal symptoms, but the effects on women in this age group are not well studied at the metabolite level.
OBJECTIVES: The primary objective of this study is to develop a robust and sensitive analytical method to identify changes to the levels of estrogen and estrogen metabolites in clinical and other biomedical samples.
METHODS: A standardized sample preparation protocol was developed for biological samples. Urine, blood plasma, and cell media were treated to deconjugate Phase II estrogen metabolites. Differential derivatization by 12C-/13C-dansyl chloride was applied to the samples and the reference standards mixture. Measurements were made using an ultrahigh-performance liquid chromatography-high resolution mass spectrometry (UHPLC-MS/MS) system using an untargeted approach with data-dependent acquisition of fragment ions.
RESULTS: Our analytical method enabled the simultaneous quantitation of 2 estrogens and 8 estrogen metabolites. Differential derivatization generated stable isotope-labeled injection standards for improved confidence in the identity of analytes; the reduced mass defect from dansylation can significantly improve the signal-to-noise ratio when a narrow mass window is selected. All estrogen metabolites had a limit of detection <10 ng/mL, and a linear signal response over 3 orders of magnitude. The untargeted approach allows for future data mining for other metabolites of interest.
CONCLUSION: In a single-arm clinical trial where postmenopausal consumed a hop dietary supplement, significant decreases in all estrogens were observed, with moderate alterations to estrogen metabolism. We are currently analyzing clinical samples from several other trials. Further study using in vitro models will help identify the mechanisms of action for the observed modulations of estrogen biosynthesis and metabolism caused by botanical dietary supplements.
|Planning to mention or discuss specific products or technology of the company(ies) listed above:||