TY - JOUR
T1 - Effect of diets fortified with tomatoes or onions with variable quercetin-glycoside content on azoxymethane-induced aberrant crypt foci in the colon of rats
AU - Femia, A.P.
AU - Caderni, G.
AU - Ianni, M.
AU - Salvadori, M.
AU - Schijlen, E.G.W.M.
AU - Collins, G.
AU - Bovy, A.G.
AU - Dolara, P.
PY - 2003
Y1 - 2003
N2 - Background: Onion and tomato are vegetables widely consumed by humans and epidemiological studies show an inverse association between vegetable consumption and colon cancer risk; however, the effect on colon cancer of diets containing high levels of vegetables like onion and tomato are not clear.
Aims of the study: To investigate whether tomatoes and onions,with low or high quercetin-glycoside content, could reduce azoxymethane (AOM)-induced Aberrant Crypt Foci (ACF), preneoplastic lesions in the colon of rats.
Methods: Male Fisher 344 rats were fed the following diets: a) high fat (HF) diet (control diet); b) HF diet containing 20 % (w/w) tomatoes with a low quercetin-glycoside content (final concentration in the diet: 5 mg/kg of quercetin aglycone equivalents); c) HF diet containing 20% (w/w) high quercetin-glycoside tomatoes (100 mg/kg final concentration of quercetin aglycone equivalents); d) HF diet containing 20 % (w/w) low quercetin-glycoside onions (14 mg/kg of quercetin aglycone equivalents in the diet); e) HF diet containing 20 % (w/w) high quercetin-glycoside onions (360 mg/kg quercetin aglycone equivalents in the diet). After 2 wks of feeding, all rats were treated twice, 1 wk apart, with AOM (12 mg/kg, s. c.). The dietary treatments continued until sacrifice, 7 wks after the first injection with AOM.
Results: ACF induction did not vary in animals fed low or high quercetin-glycoside tomatoes relative to controls. On the contrary, rats fed 20% (w/w) onion-based diets, with low or high quercetin-glycoside content, showed an increase in number, multiplicity and large ACF compared to the control group (number of ACF/colon 145 ± 15 (SE), 255 ± 11 and 218 ± 16 in controls, low and high-quercetin-glycoside groups, respectively; p <0.01). Proliferative activity of the colon did not vary between animals fed control and high quercetin-glycoside tomato diet. The height of the crypts in normal mucosa of rats fed high quercetinglycoside onions was significantly increased compared to control rats (cells/emicrypt 38.4 ± 1.2 (SE) and 41.3 ± 0.6 in controls and high quercetin-glycoside onions group, p <0.05).
Conclusions: None of the diets supplemented with onion or tomato with variable quercetin-glycoside content demonstrated a potential chemopreventive effect on ACF-induction by AOM in rats
AB - Background: Onion and tomato are vegetables widely consumed by humans and epidemiological studies show an inverse association between vegetable consumption and colon cancer risk; however, the effect on colon cancer of diets containing high levels of vegetables like onion and tomato are not clear.
Aims of the study: To investigate whether tomatoes and onions,with low or high quercetin-glycoside content, could reduce azoxymethane (AOM)-induced Aberrant Crypt Foci (ACF), preneoplastic lesions in the colon of rats.
Methods: Male Fisher 344 rats were fed the following diets: a) high fat (HF) diet (control diet); b) HF diet containing 20 % (w/w) tomatoes with a low quercetin-glycoside content (final concentration in the diet: 5 mg/kg of quercetin aglycone equivalents); c) HF diet containing 20% (w/w) high quercetin-glycoside tomatoes (100 mg/kg final concentration of quercetin aglycone equivalents); d) HF diet containing 20 % (w/w) low quercetin-glycoside onions (14 mg/kg of quercetin aglycone equivalents in the diet); e) HF diet containing 20 % (w/w) high quercetin-glycoside onions (360 mg/kg quercetin aglycone equivalents in the diet). After 2 wks of feeding, all rats were treated twice, 1 wk apart, with AOM (12 mg/kg, s. c.). The dietary treatments continued until sacrifice, 7 wks after the first injection with AOM.
Results: ACF induction did not vary in animals fed low or high quercetin-glycoside tomatoes relative to controls. On the contrary, rats fed 20% (w/w) onion-based diets, with low or high quercetin-glycoside content, showed an increase in number, multiplicity and large ACF compared to the control group (number of ACF/colon 145 ± 15 (SE), 255 ± 11 and 218 ± 16 in controls, low and high-quercetin-glycoside groups, respectively; p <0.01). Proliferative activity of the colon did not vary between animals fed control and high quercetin-glycoside tomato diet. The height of the crypts in normal mucosa of rats fed high quercetinglycoside onions was significantly increased compared to control rats (cells/emicrypt 38.4 ± 1.2 (SE) and 41.3 ± 0.6 in controls and high quercetin-glycoside onions group, p <0.05).
Conclusions: None of the diets supplemented with onion or tomato with variable quercetin-glycoside content demonstrated a potential chemopreventive effect on ACF-induction by AOM in rats
KW - chemopreventive agents
KW - f344 rats
KW - cancer
KW - carcinogenesis
KW - consumption
KW - acid
KW - chalcone
KW - rectum
KW - fruit
KW - rutin
U2 - 10.1007/s00394-003-0431-5
DO - 10.1007/s00394-003-0431-5
M3 - Article
VL - 42
SP - 346
EP - 352
JO - European Journal of Nutrition
JF - European Journal of Nutrition
SN - 1436-6207
IS - 6
ER -