Tags

Type your tag names separated by a space and hit enter

A review of animal model studies of tomato carotenoids, lycopene, and cancer chemoprevention.
Exp Biol Med (Maywood). 2002 Nov; 227(10):864-8.EB

Abstract

There are relatively few reports on the cancer chemopreventive effects of lycopene or tomato carotenoids in animal models. The majority, but not all, of these studies indicate a protective effect. Inhibitory effects were reported in two studies using aberrant crypt foci, an intermediate lesion leading to colon cancer, as an end point and in two mammary tumor studies, one using the dimethylbenz(a)anthracene model, and the other the spontaneous mouse model. Inhibitory effects were also reported in mouse lung and rat hepatocarcinoma and bladder cancer models. However, a report from the author's laboratory found no effect in the N-nitrosomethylurea-induced mammary tumor model when crystalline lycopene or a lycopene-rich tomato carotenoid oleoresin was administered in the diet. Unfortunately, because of differences in routes of administration (gavage, intraperitoneal injection, intra-rectal instillation, drinking water, and diet supplementation), species and strain differences, form of lycopene (pure crystalline, beadlet, mixed carotenoid suspension), varying diets (grain-based, casein based) and dose ranges (0.5-500 ppm), no two studies are comparable. It is clear that the majority of ingested lycopene is excreted in the feces and that 1000-fold more lycopene is absorbed and stored in the liver than accumulates in other target organs. Nonetheless, physiologically significant (nanogram) levels of lycopene are assimilated by key organs such as breast, prostate, lung, and colon, and there is a rough dose-response relationship between lycopene intake and blood levels. Pure lycopene was absorbed less efficiently than the lycopene-rich tomato carotenoid oleoresin and blood levels of lycopene in rats fed a grain-based diet were consistently lower than those in rats fed lycopene in a casein-based diet. The latter suggests that the matrix in which lycopene is incorporated is an important determinant of lycopene uptake. A number of issues remain to be resolved before any definitive conclusions can be drawn concerning the anticancer effects of lycopene. These include the following: the optimal dose and form of lycopene, interactions among lycopene and other carotenoids and fat soluble vitamins such as vitamin E and D, the role of dietary fat in regulating lycopene uptake and disposition, organ and tissue specificity, and the problem of extrapolation from rodent models to human populations.

Authors+Show Affiliations

American Health Foundation, 1 Dana Road, Valhalla, NY 10595, USA. Leonard_cohen@nymc.edu

Pub Type(s)

Journal Article
Review

Language

eng

PubMed ID

12424327

Citation

Cohen, Leonard A.. "A Review of Animal Model Studies of Tomato Carotenoids, Lycopene, and Cancer Chemoprevention." Experimental Biology and Medicine (Maywood, N.J.), vol. 227, no. 10, 2002, pp. 864-8.
Cohen LA. A review of animal model studies of tomato carotenoids, lycopene, and cancer chemoprevention. Exp Biol Med (Maywood). 2002;227(10):864-8.
Cohen, L. A. (2002). A review of animal model studies of tomato carotenoids, lycopene, and cancer chemoprevention. Experimental Biology and Medicine (Maywood, N.J.), 227(10), 864-8.
Cohen LA. A Review of Animal Model Studies of Tomato Carotenoids, Lycopene, and Cancer Chemoprevention. Exp Biol Med (Maywood). 2002;227(10):864-8. PubMed PMID: 12424327.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - A review of animal model studies of tomato carotenoids, lycopene, and cancer chemoprevention. A1 - Cohen,Leonard A, PY - 2002/11/9/pubmed PY - 2002/12/20/medline PY - 2002/11/9/entrez SP - 864 EP - 8 JF - Experimental biology and medicine (Maywood, N.J.) JO - Exp. Biol. Med. (Maywood) VL - 227 IS - 10 N2 - There are relatively few reports on the cancer chemopreventive effects of lycopene or tomato carotenoids in animal models. The majority, but not all, of these studies indicate a protective effect. Inhibitory effects were reported in two studies using aberrant crypt foci, an intermediate lesion leading to colon cancer, as an end point and in two mammary tumor studies, one using the dimethylbenz(a)anthracene model, and the other the spontaneous mouse model. Inhibitory effects were also reported in mouse lung and rat hepatocarcinoma and bladder cancer models. However, a report from the author's laboratory found no effect in the N-nitrosomethylurea-induced mammary tumor model when crystalline lycopene or a lycopene-rich tomato carotenoid oleoresin was administered in the diet. Unfortunately, because of differences in routes of administration (gavage, intraperitoneal injection, intra-rectal instillation, drinking water, and diet supplementation), species and strain differences, form of lycopene (pure crystalline, beadlet, mixed carotenoid suspension), varying diets (grain-based, casein based) and dose ranges (0.5-500 ppm), no two studies are comparable. It is clear that the majority of ingested lycopene is excreted in the feces and that 1000-fold more lycopene is absorbed and stored in the liver than accumulates in other target organs. Nonetheless, physiologically significant (nanogram) levels of lycopene are assimilated by key organs such as breast, prostate, lung, and colon, and there is a rough dose-response relationship between lycopene intake and blood levels. Pure lycopene was absorbed less efficiently than the lycopene-rich tomato carotenoid oleoresin and blood levels of lycopene in rats fed a grain-based diet were consistently lower than those in rats fed lycopene in a casein-based diet. The latter suggests that the matrix in which lycopene is incorporated is an important determinant of lycopene uptake. A number of issues remain to be resolved before any definitive conclusions can be drawn concerning the anticancer effects of lycopene. These include the following: the optimal dose and form of lycopene, interactions among lycopene and other carotenoids and fat soluble vitamins such as vitamin E and D, the role of dietary fat in regulating lycopene uptake and disposition, organ and tissue specificity, and the problem of extrapolation from rodent models to human populations. SN - 1535-3702 UR - https://www.unboundmedicine.com/medline/citation/12424327/A_review_of_animal_model_studies_of_tomato_carotenoids_lycopene_and_cancer_chemoprevention_ L2 - http://journals.sagepub.com/doi/full/10.1177/153537020222701005?url_ver=Z39.88-2003&rfr_id=ori:rid:crossref.org&rfr_dat=cr_pub=pubmed DB - PRIME DP - Unbound Medicine ER -