UGT2B4 is mainly involved in the
glucuronidation of
hyodeoxycholic acid, a
bile acid, and
catechol-
estrogens, such as 17-
epiestriol and 4-hydroxy-
estrone. The expression of the UGT2B4 enzyme is upregulated by the
farnesoid X receptor (FXR), a
nuclear receptor which is activated by bile acids. These same bile acids are substrates for the UGT2B4 enzyme. Hence upregulation of UGT2B4 by activated FXR provides a mechanism for the detection, conjugation and subsequent elimination of toxic bile acids. ==References==