U.S. flag

An official website of the United States government

Dot gov

The .gov means it's official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you're on a federal government site.


The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.


ICCVAM Biennial Report 2018-2019

Biennial Progress Report 2018-2019 Interagency Coordinating Committee on the Validation of Alternative Methods

Evaluation of FXR-active Chemicals Identified from Tox21 Screening

Farnesoid X receptor alpha (FXRα) is a member of the nuclear receptor superfamily involved in bile acid homeostasis, glucose metabolism, lipid homeostasis, and hepatic regeneration. NIEHS and NIH scientists with academic and industry collaborators evaluated substances identified in Tox21 HTS in vitro screens as FXRα agonists and antagonists using four experimental approaches. The study generally confirmed quantitative HTS in vitro results, provided data on protein:protein interactions and receptor docking, and translated those results to an in vivo system. A poster describing the study (Hamm et al.) was presented at the 2018 Society of Toxicology annual meeting.