Phenethyl isothiocyanate and indole‐3‐carbinol from cruciferous vegetables, but not furanocoumarins from apiaceous vegetables, reduced PhIP‐induced DNA adducts in Wistar rats

Abstract

Effects of phytochemicals on metabolic outcomes and markers of carcinogenesis might differ from fresh vegetables, thus limiting the inferences that one can draw from the effects of purified phytochemicals on the health benefits of the vegetables from which they derive.

Apiaceous Vegetables and Cruciferous Phytochemicals Reduced PhIP-DNA Adducts in Prostate but Not in Pancreas of Wistar Rats

“…This lack of effect in the fresh CRU group could be because PEITC and I3C levels fed in the phytochemical diet were matched to the total glucosinolate content in our fresh cruciferous feeding due to the variety of glucosinolates in the vegetables with potential bioactivity, yet lack commercially available standards for individual measurement as previously discussed. 7 Thus, these two specific components were higher than in our fresh cruciferous feeding, which would have contained a number of different glucosinolates in addition to the parent compounds of PEITC and I3C. Possibly, other factors might have influenced this difference, such as bioavailability or incomplete hydrolysis of parent glucosinolates.…”

“…6 We also demonstrated that purified phytochemicals from cruciferous vegetables decreased PhIP-DNA adducts in rat colon, but with less effect from their whole vegetable source. 7 However, there is no study that examined the effects of combined intake of two different vegetable families or their phytochemicals on prostate and pancreas PhIP-DNA adducts. Hence, we exam-ined here whether feeding the aforementioned would result in similar effects in rat prostate and pancreas as seen in colon.…”

“…In experiment II, the supplemented diets contained one of three different phytochemical combinations at levels matching their whole vegetable counterpart fed in experiment I: glucosinolate metabolites (PEITC and I3C; P+I, 183 mg of each compound/kg diet; n = 10), furanocoumarins (5-methoxypsoralen , 8-methoxypsoralen , and isopimpinellin; FC, 0.606, 0.299, and 1.24 mg/kg diet, respectively; n = 10) and the combination of the phytochemicals (COMBO; n = 10) as previously described and discussed. 7 AIN-93G purified diet was used for control groups (n = 10-12). After acclimation, rats were divided into five experimental feeding groups, including negative and positive control groups.…”

“…Prostate and pancreatic tissues were harvested from the same animals we previously utilized. 6,7 PhIP-DNA adducts in prostate and pancreas were measured using an online columnswitching LC-MS/MS method in which the ratio between unlabeled PhIP-DNA adducts and isotopically labeled internal standard was used to quantify the adduct levels. 6 Results are expressed as meanstandard error of the mean.…”

Phytochemicals and Gastrointestinal Cancer: Cellular Mechanisms and Effects to Change Cancer Progression

“…Additionally, these vegetables induce acute oxidative stress through the inhibition of P38 MAPK, which inhibits Nrf2-Keap 1 dissociation (Table 1) [164]. Cruciferous vegetables guard against colorectal cancer through several mechanisms: (i) the modulation of detoxification enzymes (Figure 2), (ii) the induction of cellular apoptosis, and (iii) the controlling of cancer cellular growth through cell cycle arrest [165][166][167]. A meta-analysis study has shown that cruciferous vegetables significantly reduce the risk of gastric and colorectal cancer by 19% and 8%, respectively [168].…”