A new study, published in the Journal of Agricultural and Food Chemistry, reports that biochemicals in the pomegranate slow the growth of prostate cancer cells. These biochemicals, "ellagitannins" and their metabolites, are "shown to be concentrated to a high degree in mouse prostate tissues," wrote the authors.
The current study contributes to the increasing body of evidence demonstrating the prostate cancer chemopreventive potential of pomegranate. The fruit, a rich source of antioxidants, has been linked to improved heart health as well. Other varied claims have been made including protecting against prostate cancer and slowing cartilage loss in arthritis. One major grower and supplier of pomegranates has quite a large research program going, and collaboration with numerous research labs. (See link at headline of this post).
It is the antioxidants present in the fruit, and particularly compounds like punicalagin (which accounts for about half of the fruit's antioxidant ability) that are behind the proposed anti-cancer effects observed in this new study by researchers from the University of California at Los Angeles. Their work suggests that the ellagitannins may also play a role in prostate cancer protection.
Seeram and co-workers looked at the effect of ellagitannins and metabolites to accumulate in the tissues in male mice.
"It is unclear why pomegranate ellagitannin metabolites localize at higher levels in prostate, colon, and intestinal tissues relative to the other organs studied," wrote the authors. This suggests the potential for pomegranate products to play a role in prostate cancer chemoprevention, per the authors.
When the researchers investigated the potential of the pomegranate extract to inhibit the growth of prostate cancer cells grafted onto mice with impaired immune function, the pomegranate extract was found to significantly inhibit the growth of the grafted tumors.
"Future animal studies using preclinical chemoprevention models and human studies evaluating metabolite uptake into human prostate tissue, together with studies of the effects of these metabolites on relevant tissue biomarkers, are warranted," concluded the researchers.