A recently published study investigated the potential benefits of ellagitannins, which are constituents of pomegranate. The effects of ellagitannins on the cytochrome P450 enzyme CYP1B1 were studied in regards to the effect this enzyme has on prostate cancer development. Cytochrome P450 enzymes metabolize thousands of endogenous and exogenous compounds including drugs, normal metabolites and toxic compounds. Cytochrome P450 1B1 is an enzyme known to be highly expressed in several human cancers but not in healthy tissues. Additionally, the metabolites of pomegranate juice ellagitannins localize to particular areas of the body including the prostate gland.
In this study, pomegranate constituents and metabolites including urolithin A, urolithin B, urolithin C, punicalins and punicalagins were evaluated for their effect on the cytochrome P450 enzymes.
The results showed that urolithin A, which is produced by the gastrointestinal micro-organisms ’ metabolism of ellagitannins, was the most potent inhibitor of CYP1B1-mediated activity. Additionally, urolithin A selectively inhibited CYP1B1 over CYP1A1 by 2-fold, which is important as CYP1A1 is associated with anti-cancer activity. In prostate cancer cells, urolithins were found to decrease CYP1B1 activity and expression.
The researchers believe that their study has suggested a previously unknown mechanism of action of pomegranate juice constituents and that systemically available metabolites of pomegranate juice could lower the incidence of prostate cancer initiation.
Reference:
Kasimsetty SG, Bialonska D, Reddy MK, Thornton C, Willett KL, Ferreira D. Effects of Pomegranate Chemical Constituents/Intestinal Microbial Metabolites on CYP1B1 in 22Rv1 Prostate Cancer Cells. J Agric Food Chem. 2009 Oct 26.
