Format

Send to

Choose Destination
Mol Nutr Food Res. 2014 Oct;58(10):1962-9. doi: 10.1002/mnfr.201400245. Epub 2014 Sep 16.

Pharmacokinetics of prenylated hop phenols in women following oral administration of a standardized extract of hops.

Author information

1
UIC/NIH Center for Botanical Dietary Supplements Research, Department of Medicinal Chemistry and Pharmacognosy, University of Illinois College of Pharmacy, Chicago, IL, USA.

Abstract

SCOPE:

Women seeking alternatives to hormone-replacement therapy for menopausal symptoms often try botanical dietary supplements containing extracts of hops (Humulus lupulus L.). Hops contain 8-prenylnaringenin (8-PN), a potent phytoestrogen, the related flavanones 6-prenylnaringenin and isoxanthohumol (IX), and the prenylated chalcone xanthohumol (XN).

METHODS AND RESULTS:

After chemically and biologically standardizing an extract of spent hops to these marker compounds, an escalating dose study was carried out in menopausal women to evaluate safety and pharmacokinetics. 8-PN, 6-prenylnaringenin, IX, and XN, sex hormones, and prothrombin time were determined in blood samples and/or 24 h urine samples. There was no effect on sex hormones or blood clotting. The maximum serum concentrations of the prenylated phenols were dose-dependent and were reached from 2 to 7 h, indicating slow absorption. The marker compounds formed glucuronides that were found in serum and urine. Secondary peaks at 5 h in the serum concentration-time curves indicated enterohepatic recirculation. The serum concentration-time curves indicated demethylation of IX to form 8-PN and cyclization of XN to IX. Slow absorption and enterohepatic recirculation contributed to half-lives exceeding 20 h.

CONCLUSION:

This human study indicated long half-lives of the estrogenic and proestrogenic prenylated phenols in hops but no acute toxicity.

KEYWORDS:

8-Prenylnaringenin; Hops; Isoxanthohumol; Pharmacokinetics; Xanthohumol

PMID:
25045111
PMCID:
PMC4265473
DOI:
10.1002/mnfr.201400245
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Wiley Icon for PubMed Central
Loading ...
Support Center