INDUCTION OF RAT HEPATIC AND INTESTINAL GLUTATHIONE S-TRANSFERASES AND GLUTATHIONE BY DIETARY NATURALLY-OCCURRING ANTICARCINOGENS

Effects of dietary naturally occurring anticarcinogens; quercetin, fla vone, ellagic acid, ferulic acid, tannic acid, curcumin, coumarin, alp ha-angelicalactone, fumaric acid and Brussels sprouts on male Wistar r at hepatic and intestinal (i) glutathione S-transferases (GST) enzyme activity, (ii) GST isozyme levels and (iii) glutathione (GSH) content were investigated. GST enzyme activity was significantly increased by all anticarcinogens tested, except fumaric acid, at least at one of th e five sites investigated: proximal, middle, distal small intestine, l arge intestine and liver. Only alpha-angelicalactone gave an enhanced GST enzyme activity at all five sites. Large intestinal GST enzyme act ivity was increased only by quercetin (175%) and alpha-angelicalactone (138%). Concomitant changes in GST isozyme levels occurred. Class alp ha GSTs were induced in 50% of the cases, especially in liver and uppe r parts of the intestine by quercetin, flavone, coumarin and alpha-ang elicalactone. GST class pi levels were enhanced only at one site by qu ercetin, coumarin and alpha-angelicalactone. GST class mu changed in 1 4% of the cases, most profoundly in proximal and middle small intestin e by flavone, coumarin and alpha-angelicalactone. Tannic acid and fuma ric acid gave a significant raise in class alpha GSTs at almost all si tes, whereas overall GST enzyme activity hardly changed. GSH was incre ased at various sites in 14% of the cases by Brussels sprouts, quercet in, flavone and alpha-angelicalactone. These data demonstrate that mos t anticarcinogens, in particular flavone, coumarin and alpha-angelical actone, enhance GST activity in liver and intestine, mainly by inducti on of class alpha and mu isozymes.