| ABSTRACT: |
|
Topical application of ellagic acid, a naturally occurring dietary
plant phenol, to Balb/C mice resulted in significant protection against
3-methylcholanthrene (MCA)-induced skin tumorigenesis. Ellagic acid was
found to be an effective inhibitor of tumor formation whether the tumor
data are considered as percent mice with tumors, cumulative number of
tumors, tumors per mouse or tumors per tumor bearing animal as a function
of the number of weeks on test. By 8, 10, 12, 14, and 16 weeks of testing,
the number of tumors per mouse in the group receiving MCA alone was 2.0,
3.4, 4.0, 4.9 and 5.3, respectively, whereas the corresponding numbers in
the group receiving MCA plus 2 mumol ellagic acid were 0, 0.3, 0.4, 0.6
and 1.2, respectively. At the termination of the experiment (16 weeks)
aryl hydrocarbon hydroxylase (AHH) activity in skin and liver and the
extent of 3H-BP-binding to skin, liver and lung DNA were determined and
both of these parameters were found to be significantly inhibited in the
animals treated with ellagic acid. These results indicate that ellagic
acid can inhibit the metabolism of polyaromatic hydrocarbons and modulate
skin carcinogenesis induced by these chemicals. |