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Tomato lycopene and its role in chronic diseases

Authors:

Abstract

Lycopene is a carotenoid that is present in tomatoes, processed tomato products and other fruits. It is one of the most potent antioxidants among dietary carotenoids. Dietary intake of tomatoes and tomato products containing lycopene has been shown to be associated with a decreased risk of chronic diseases, such as cancer and cardiovascular disease. Serum and tissue lycopene levels have been found to be inversely related to the incidence of several types of cancer, including breast cancer and prostate cancer. Although the antioxidant properties of lycopene are thought to be primarily responsible for its beneficial effects, evidence is accumulating to suggest that other mechanisms may also be involved. In this article we outline the possible mechanisms of action of lycopene and review the current understanding of its role in human health and disease prevention.
CMAJ • SEPT. 19, 2000; 163 (6) 739
© 2000 Canadian Medical Association or its licensors
Review
Synthèse
Drs. Agarwal and Rao are
with the Department of
Nutritional Sciences, Faculty
of Medicine, University of
Toronto, Toronto, Ont.
This article has been peer reviewed.
CMAJ 2000;163(6):739-44
Abstract
LYCOPENE IS A CAROTENOID THAT IS PRESENT IN TOMATOES
, processed tomato products
and other fruits. It is one of the most potent antioxidants among dietary
carotenoids. Dietary intake of tomatoes and tomato products containing lycopene
has been shown to be associated with a decreased risk of chronic diseases, such as
cancer and cardiovascular disease. Serum and tissue lycopene levels have been
found to be inversely related to the incidence of several types of cancer, including
breast cancer and prostate cancer. Although the antioxidant properties of lycopene
are thought to be primarily responsible for its beneficial effects, evidence is accu-
mulating to suggest that other mechanisms may also be involved. In this article we
outline the possible mechanisms of action of lycopene and review the current un-
derstanding of its role in human health and disease prevention.
C
hronic diseases, including cancer and cardiovascular disease, are the main
causes of death in the Western world. Along with genetic factors and age,
lifestyle and diet are also considered important risk factors.
1,2
About 50% of
all cancers have been attributed to diet.
3
Oxidative stress induced by reactive oxygen species is one of the main foci of re-
cent research related to cancer and cardiovascular disease. Reactive oxygen species
are highly reactive oxidant molecules that are generated endogenously through reg-
ular metabolic activity, lifestyle activity and diet. They react with cellular compo-
nents, causing oxidative damage to such critical cellular biomolecules as lipids, pro-
teins and DNA. There is strong evidence that this damage may play a significant
role in the causation of several chronic diseases.
4–7
Antioxidants are protective agents that inactivate reactive oxygen species and
therefore significantly delay or prevent oxidative damage. Antioxidants such as su-
peroxide dismutase, catalase and glutathione peroxidase are naturally present within
human cells. In addition, antioxidants such as vitamin E, vitamin C, polyphenols
and carotenoids are available from food. Current dietary guidelines to combat
chronic diseases, including cancer and coronary artery disease, recommend in-
creased intake of plant foods, including fruits and vegetables, which are rich sources
of antioxidants.
8,9
The role of dietary antioxidants, including vitamin C, vitamin E,
carotenoids and polyphenols, in disease prevention has received much attention in
recent years.
10–12
These antioxidants appear to have a wide range of anticancer and
antiatherogenic properties.
10–14
These observations may explain the epidemiological
data indicating that diets rich in fruits and vegetables are associated with a reduced
risk of numerous chronic diseases.
1,15–17
Another dietary antioxidant thought to be important in the defence against oxida-
tion is lycopene, of which tomatoes are an important dietary source.
18,19
Lycopene is
a natural pigment synthesized by plants and microorganisms but not by animals. It is
a carotenoid, an acyclic isomer of β-carotene. Lycopene is a highly unsaturated hy-
drocarbon containing 11 conjugated and 2 unconjugated double bonds. As a polyene
it undergoes cis-trans isomerization induced by light, thermal energy and chemical
reactions (Fig. 1).
20,21
Lycopene from natural plant sources exists predominantly in an
all-trans configuration, the most thermodynamically stable form.
20,21
In human
plasma, lycopene is present as an isomeric mixture, with 50% as cis isomers.
22
Lycopene is one of the most potent antioxidants,
23–26
with a singlet-oxygen-
Tomato lycopene and its role
in human health and chronic diseases
Sanjiv Agarwal, Akkinappally Venketeshwer Rao
Table of Contents
Return to September 19, 2000
quenching ability twice as high as that of β-carotene and
10 times higher than that of α-tocopherol.
26
It is the most
predominant carotenoid in human plasma. Its level is af-
fected by several biological and lifestyle factors.
18,27
Owing
to their lipophilic nature, lycopene and other carotenoids
are found to concentrate in low-density and very-low-den-
sity lipoprotein fractions of the serum.
19
Lycopene is also
found to concentrate in the adrenal gland, testes, liver and
prostate gland, where it is the most prominent caro-
tenoid.
28–31
Table 1 shows the lycopene levels in various hu-
man and rat tissues.
28–32
Tissue-specific lycopene distribu-
tion may be important in the role of this antioxidant.
However, unlike other carotenoids, lycopene levels in
serum or tissues do not correlate well with overall intake
of fruits and vegetables.
33,34
Mechanisms of action
The biological activities of carotenoids such as β-
carotene are related in general to their ability to form vita-
min A within the body.
19
Since lycopene lacks the β-ionone
ring structure, it cannot form vitamin A.
35
Its biological ef-
fects in humans have therefore been attributed to mecha-
nisms other than vitamin A. Two major hypotheses have
been proposed to explain the anticarcinogenic and an-
tiatherogenic activities of lycopene: nonoxidative and ox-
idative mechanisms. The proposed mechanisms for the role
of lycopene in the prevention of chronic diseases are sum-
marized in Fig. 2.
Among the nonoxidative mechanisms, the anticarcino-
genic effects of lycopene have been suggested to be due to
regulation of gap-junction communication in mouse em-
bryo fibroblast cells.
36,37
Lycopene is hypothesized to sup-
press carcinogen-induced phosphorylation of regulatory
proteins such as p53 and Rb antioncogenes and stop cell
division at the G
0
–G
1
cell cycle phase.
38
Astorg and col-
leagues
39
proposed that lycopene-induced modulation of
the liver metabolizing enzyme, cytochrome P450 2E1, was
the underlying mechanism of protection against carcino-
gen-induced preneoplastic lesions in the rat liver. Prelimi-
nary in vitro evidence also indicates that lycopene reduces
cellular proliferation induced by insulin-like growth fac-
tors, which are potent mitogens, in various cancer cell
lines.
40
Regulation of intrathymic T-cell differentiation (im-
munomodulation) was suggested to be the mechanism for
suppression of mammary tumour growth by lycopene
treatments in SHN retired mice.
41,42
Lycopene also has
been shown to act as a hypocholesterolemic agent by
inhibiting HMG–CoA (3-hydroxy-3-methylglutaryl–
coenzyme A) reductase.
43
Lycopene has been hypothesized to prevent carcinogen-
esis and atherogenesis by protecting critical cellular bio-
molecules, including lipids, lipoproteins, proteins and
DNA.
44–46
In healthy human subjects, lycopene- or tomato-
free diets resulted in loss of lycopene and increased lipid
oxidation,
47
whereas dietary supplementation with lycopene
Agarwal and Rao
740 JAMC • 19 SEPT. 2000; 163 (6)
Table 1: Re
p
orted mean l
y
co
p
ene levels in human
28–31
and rat
32
tissues*
Mean lycopene level (and SD),
nmol/g wet weight
Tissue Humans Rats
Testes 4.3421.36 NA
Spleen NA 21.21 (2.22)
Adrenal gland 1.9021.60 NA
Liver 1.285.72 20.30 (1.90)
Prostate gland 0.80 0.32 (0.06)
Breast 0.78 NA
Pancreas 0.70 NA
Lung 0.220.57 0.115 (0.015)
Heart NA 0.08 (0.03)
Kidney 0.150.62 NA
Colon 0.31 0.046 (0.006)
Skin 0.42 NA
Ovary 0.30 NA
Stomach 0.20 NA
Brain ND 0.017 (0.006)
Note: SD = standard deviation, NA = not available, ND = not detectable.
*Fischer 344 male rats were fed the AIN-93M diet supplemented with 10 ppm o
f
lycopene for 2 months (AIN = American Institute of Nutrition).
Fig. 1: Structures of trans and cis isomers of lycopene.
for 1 week increased serum lycopene levels and reduced en-
dogenous levels of oxidation of lipids, proteins, lipoproteins
and DNA.
44,45
Patients with prostate cancer were found to
have low levels of lycopene and high levels of oxidation of
serum lipids and proteins.
48
Epidemiological evidence
Risk of cancer
The Mediterranean diet, which is rich in vegetables and
fruits, including tomatoes, has been suggested to be re-
sponsible for the lower cancer rates in that region.
49
Dietary
intake of tomatoes and tomato products has been found to
be associated with a lower risk of a variety of cancers in sev-
eral epidemiological studies.
50
A high intake of tomatoes
was linked to protective effects against digestive tract can-
cers in a case–control study
51
and a 50% reduction in rates
of death from cancers at all sites in an elderly US popula-
tion.
52
The most impressive results come from the US
Health Professionals Follow-up Study, which evaluated the
intake of various carotenoids and retinol, from a food-fre-
quency questionnaire, in relation to risk of prostate can-
cer.
53
The estimated intake of lycopene from various
tomato products was inversely related to the risk of prostate
cancer. This result was not observed with any other caro-
tenoid. A reduction in risk of almost 35% was observed for
a consumption frequency of 10 or more servings of tomato
products per week, and the protective effects were even
stronger with more advanced or aggressive prostate cancer.
In recent studies serum and tissue levels of lycopene were
shown to be inversely associated with the risk of breast can-
cer
54
and prostate cancer;
48,55
no significant association with
other important carotenoids, including β-carotene, was ob-
served.
48,55
Giovannucci
50
recently reviewed 72 epidemiolog-
ical studies, including ecological, case–control, dietary and
blood-specimen-based investigations of tomatoes, tomato-
based products, lycopene and cancer. In 57 studies there
was an inverse association between tomato intake or circu-
lating lycopene levels and risk of several types of cancer; in
35 cases the association was statistically significant. None of
the studies showed adverse effects of high tomato intake or
high lycopene levels.
Although the epidemiological evidence of the role of
Role of lycopene in human health
CMAJ SEPT. 19, 2000; 163 (6) 741
Fig. 2: Proposed mechanisms for the role of lycopene in preventing chronic diseases. Dietary lycopene may increase the lyco-
pene status in the body and, acting as an antioxidant, may trap reactive oxygen species, increase the overall antioxidant poten-
tial or reduce the oxidative damage to lipid (lipoproteins, membrane lipids), proteins (important enzymes) and DNA (genetic
material), thereby lowering oxidative stress. This reduced oxidative stress may lead to reduced risk for cancer and cardiovascu-
lar disease. Alternatively, the increased lycopene status in the body may regulate gene functions, improve intercell communica-
tion, modulate hormone and immune response, or regulate metabolism, thus lowering the risk for chronic disease. These mech-
anisms may also be interrelated and may operate simultaneously to provide health benefits.
Christine Kenney
lycopene in cancer prevention is persuasive, this role re-
mains to be proven. There are few human intervention tri-
als investigating the effectiveness of lycopene in lowering
cancer risk. Most of the workers have investigated the ef-
fects of tomato or tomato product (lycopene) supplementa-
tion on oxidative damage to lipids, proteins and DNA.
44–46
A
preliminary report has indicated that tomato extract sup-
plementation in the form of oleoresin capsules lowers the
levels of prostate-specific antigen in patients with prostate
cancer.
56
Risk of cardiovascular disease
Oxidation of low-density lipoproteins, which carry cho-
lesterol into the blood stream, may play an important role in
the causation of atherosclerosis.
6,57,58
Antioxidant nutrients are
believed to slow the progression of atherosclerosis because of
their ability to inhibit damaging oxidative processes.
14,58–60
Several controlled clinical trials and epidemiological studies
have provided evidence for the protective effect of vitamin E,
which has been ascribed to its antioxidant properties.
14,61,62
However, in the recently completed Heart Outcomes Pre-
vention Evaluation (HOPE) Study, supplementation with
400 IU/d of vitamin E for 4.5 years did not result in any ben-
eficial effects on cardiovascular events in patients at high
risk.
63
In contrast, other studies indicated that consuming
tomatoes and tomato products containing lycopene reduced
the risk of cardiovascular disease.
43,44,64
In a multicentre case–control study, the relation between
antioxidant status and acute myocardial infarction was eval-
uated.
64
Subjects were recruited from 10 European countries
to maximize the variability in exposure within the study.
Adipose tissue antioxidant levels, which are better indicators
of long-term exposure than blood antioxidant levels, were
used as markers of antioxidant status. Biopsy specimens of
adipose tissue were taken directly after the infarction and
were analysed for various carotenoids. After adjustment for
a range of dietary variables, only lycopene levels, and not
β-carotene levels, were found to be protective.
A study from Johns Hopkins University, Baltimore,
showed that smokers with low levels of circulating caro-
tenoids were at increased risk for subsequent myocardial
infarction.
65
Lower blood lycopene levels were also found
to be associated with increased risk for and death from
coronary artery disease in a population study comparing
Lithuanian and Swedish cohorts with different rates of
death from coronary artery disease.
66
Food sources and bioavailability
Red fruits and vegetables, including tomatoes, water-
melons, pink grapefruits, apricots and pink guavas, contain
lycopene.
20
Processed tomato products, such as juice,
ketchup, paste, sauce and soup, all are good dietary sources
of lycopene. In a recent study in our laboratory, the average
daily dietary intake of lycopene, assessed by means of a
food-frequency questionnaire, was estimated to be 25 mg/d
with processed tomato products, accounting for 50% of the
total daily intake
67
(Table 2).
Although comparative bioavailability values for lycopene
from different tomato products are unknown, lycopene
from processed tomato products appears to be more bio-
available than that from raw tomatoes.
68,69
The release of ly-
copene from the food matrix due to processing, the pres-
ence of dietary lipids and heat-induced isomerization from
an all-trans to a cis conformation enhance lycopene bioavail-
ability.
18
The bioavailability of lycopene is also affected by
the dosage and the presence of other carotenoids, such as
β-carotene: Johnson and associates
70
found that the bioavail-
ability of lycopene was significantly higher when it was in-
gested along with β-carotene than when ingested alone.
Future directions
The current dietary recommendation to increase the
consumption of fruits and vegetables rich in antioxidants
has generated interest in the role of lycopene in disease
prevention. However, the evidence thus far is mainly sug-
gestive, and the underlying mechanisms are not clearly un-
derstood. Further research is critical to elucidate the role of
lycopene and to formulate guidelines for healthy eating and
disease prevention. Areas for further study include epi-
demiological investigations based on serum lycopene levels,
bioavailability and effects of dietary factors, long-term di-
etary intervention studies, metabolism and isomerization of
lycopene and their biological significance, interaction with
other carotenoids and antioxidants, and mechanism of dis-
ease prevention.
Agarwal and Rao
742 JAMC 19 SEPT. 2000; 163 (6)
Competing interests: None declared.
Table 2: Estimates of dail
y
intake of l
y
co
p
ene from tomatoe
s
and tomato
p
roducts, as determined from a food-fre
q
uenc
y
questionnaire
67
Product
Serving
size
Lycopene
intake, mg/d
per subject
% of total
daily lycopene
intake
Tomatoes 200 g 12.70 50.5
Tomato purée 60 mL 1.02 4.1
Tomato paste 30 mL 2.29 9.1
Tomato sauce 227 mL 1.52 6.0
Spaghetti sauce 125 mL 2.44 9.7
Pizza sauce 60 mL 0.66 2.6
Chili sauce 30 mL 0.30 1.2
Tomato ketchup 15 mL 0.53 2.1
Barbecue sauce 30 mL 0.06 0.2
Tomato juice 250 mL 2.20 8.7
Tomato soup 227 mL 0.79 3.1
Clam cocktail 250 mL 0.50 2.0
Bloody Mary mix 156 mL 0.15 0.6
Total 25.16
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Agarwal and Rao
744 JAMC 19 SEPT. 2000; 163 (6)
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Venketeshwer Rao, Department of Nutritional Sciences, Faculty
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... 1,2 The fruit has a good nutritive value being rich in vitamins (A, B 1 , B 2 , B 3 , B 5 , B 6 , and C), lycopene, organic acids (citric and maleic acids), amino acids (tryptophan, threonine, leucine, isoleucine, lysine, methionine, histidine, phenylalanine and valine) and minerals such as sodium, potassium, calcium, magnesium, zinc, phosphorus and iron. [2][3][4][5][6] Among the several reviews on the plant growing abroad, [6][7][8][9][10][11][12] few studies focused on the plant waste (leaf, stem, and root) being discarded after harvesting. [13][14][15] Reports showed that these worthless plant organs are rich untapped sources of biologically active constituents belonging to different chemical classes viz.; steroidal alkaloids, flavonoids and other phenolics, 11 which encourage us to do further investigation. ...
... Similarly, Cacace and Mazza observed higher anthocyanin content from blackcurrants using aqueous ethanol until the water composition reached a maximum of 60%, thereafter, the yield dropped with further increase in solvent concentration (191). Phenolic compounds prevent oxidative damage in living systems (192) and in respect of this, scientific reports have shown polyphenol protective effect of sperm from reactive oxygen species (ROS) induced sperm damage (193). ...
Thesis
Full-text available
Male reproductive health is characterized by infertility, premature ejaculation, lack of sexual desire and erectile dysfunction. Management of the aforementioned involves use of pharmaceuticals, neutraceuticals and surgery among others. These management approaches are expensive and not well tolerated. As such, men worldwide resort to use of herbal aphrodisiacs as they are cheap, easy to access and with no side effects. Secondary metabolites have been suggested to protect the testicular cell hierarchy, positively modulate the hormonal profile, increase sperm motility and concentration. Unfortunately, scientific data in support of these aphrodisiac claims and their mechanisms of action is scanty. The aim of this study was to identify secondary metabolites and establish the mechanisms of action of three Malawi herbal aphrodisiacs Cassia abbreviata, Dioscorea bulbifera and Newtonia hildebrandtti on male reproductive system. This study, fingerprinted and quantified secondary metabolites using calorimetric methods. The atomic absorption spectroscopy of the three herbs showed the presence of magnesium, zinc chromium, arsenic, copper and manganese. After 56 days of treatment, the rat model showed positively modulated sexual hormonal profile, high progressive and total motility, high mean body and testis weight, increased seminiferous tubule diameter and germinal epithelial height compared to the untreated male albino rats. In vitro studies of human semen showed high sperm survival rate, high progressive and total motility of the human sperm. In conclusion, the three herbal aphrodisiacs appear to be strongly associated with high antioxidant capacity, presence of trace elements and secondary metabolites which elsewhere have been implicated in the reversal of male infertility through improved hormonal levels, positive structural changes in the testis, high sperm concentration, high progressive and total motility. The observed parameters are provocative and warrant further research.
... Lycopene and zeaxanthin are the two carotenoids with no pro vitamin A activity, though they play a vital role in human health, zeaxanthin and luteine (are structural isomers) accumulates in the eye where they play a very important role in the prevention of eye aging diseases such as cataracts, Bone et al. (2003). For lycopene, it serves as a very important antioxidant in the organism, that is, in the prevention of some forms of cancers and cardiovascular diseases, Argarwal and Rao (2000). Foods like pumpkin, solo papaya and water melon, which are the best sources of these carotenoids play a double role, first as a source of provitamin A and then as an antioxidant. ...
... Lycopene, through tomato sauce consumption, reduces leukocyte and prostate tissue oxidative DNA damage and decreases prostate specific antigen (PSA) level in prostate cancer patients (Chen et al., 2001). Many population studies have established a link between dietary intake of tomatoes, a major source of the antioxidant lycopene, and a reduced risk of cancer and cardiovascular diseases (Agarwa and Rao, 2000). In animal prostate cancer models, tomato supplementation showed higher effects than lycopene supplementation on carcinogenesis prevention and mortality (Imaida et al., 2001 andBoileau et al., 2003). ...
... Penelitian ini bertujuan Untuk melihat gambaran histopatologi hati tikus wistar yang diberikan jus tomat terhadap kerusakan hati yang diinduksi CCl 7,8 4. ...
Article
Liver is the largest organ in the abdominal cavity. As the center of metabolism in the body, liver is potentially damaged by exposure of toxic substances, inter alia carbon tetrachloride (CCl4). Metabolism of carbon tetrachloride (CCl4) produces CCl3 free radicals that can damage the liver. In Indonesia, there are a lot of natural ingredients that have antioxidant properties, such as tomato. Lycopene in tomatoes contains antioxidant compounds that can prevent damages due to free radical. This study aimed to obtain liver histopathological changes of wistar rats fed with tomato juice after being induced of carbon tetrachloride (CCl4). This was an experimental study, using 10 wistar rats which were divided into 4 groups. Group I was the negative control; group II was induced with CCl4 0,05 cc/day and was terminated on day 6; group III was induced with CCl4 0,05 cc/day and was given tomato juice 3 ml/day, and terminated on day 13; group IV was induced by CCl4 0,05 cc/day, given regular pellets, and terminated on day 13. The results showed that group II had histopathological changes of the liver indicating fatty liver, meanwhile group III showed regeneration of nearly all liver cells. Conclusion: Administration of tomato juice after the induction of 3 ml carbon tetrachloride (CCl4) for 7 day showed regeneration of almost all liver cells. Keywords: histopathological changes of the liver, carbon tetrachloride, tomato juice. Abstrak: Hati merupakan organ terbesar dalam rongga abdomen, dan pusat metabolisme tubuh dengan fungsi yang sangat kompleks dan sangat berpotensi mengalami kerusakan akibat terpapar oleh bahan-bahan toksik, salah satunya yaitu karbon tertraklorida (CCL4). Metabolisme CCl4 menghasilkan radikal bebas CCl3 yang dapat merusak hati. Di Indonesia terdapat banyak sekali bahan-bahan alami yang mempunyai kandungan antioksidan, salah satunya yaitu tomat. Tomat mengandung senyawa likopen sebagai antioksidan yang dapat mencegah kerusakan jaringan akibat radikal bebas. Penelitian ini bertujuan untuk mendapatkan gambaran histopatologi hati tikus wistar yang diberi jus tomat pasca induksi karbon tetraklorida (CCl4). Metode penelitian ialah eksperimental. Sampel sebanyak 10 ekor tikus wistar yang dibagi dalam 4 kelompok. Kelompok I sebagai kontrol negatif; kelompok II diinduksi CCl4 0,05cc/perhari dan diterminasi hari ke-6; kelompok III diinduksi CCl4 0,05 cc/hari kemudian diberikan jus tomat 3ml/hari; dan kelompok IV diinduksi CCl4 0,05 cc/hari kemudian diberikan pelet biasa dan diterminasi hari ke-13. Hasil penelitian menunjukkan pada pemberian CCl4 pada tikus wistar selama 5 hari terdapat gambaran morfologik perlemakan sel hati. Pemberian jus tomat dosis 3 ml pasca induksi karbon tetraklorida (CCl4) menunjukkan terjadinya regenerasi pada hampir seluruh sel-sel hati. Simpulan: Pemberian jus tomat dosis 3 ml pasca induksi karbon tetraklorida (CCl4) selama 7 hari menunjukkan regenerasi pada hampir seluruh sel-sel hati. Kata kunci: gambaran histopatologi hati, karbon tetraklorida, jus tomat.
... lação das vias de transdução de sinal (18,19). A atividade antioxidante do licopeno tem sido extensivamente estudada (20,21), sendo o seu efeito melhorado pela adição de outros antioxidantes (22,23). ...
Article
div>Introdução: O câncer de cólon é um grave problema de saúde pública, sendo uma das principais causas de mortalidade por câncer em todo o mundo. A busca por novas opções terapêuticas para os diferentes tipos de câncer é um dos assuntos de maior interesse na atualidade da pesquisa de compostos bioativos. Possíveis estratégias para a prevenção do câncer podem ser alcançadas utilizando agentes quimiopreventivos, como o licopeno, de modo a reduzir ou eliminar os efeitos deletérios da exposição humana a potenciais carcinógenos. Objetivo: avaliar a influência do licopeno e beta-caroteno sobre a proliferação, ciclo celular e apoptose da linhagem T84 de carcinoma de cólon humano. Metodologia: As células T84 foram cultivadas com DMEM, suplementado com 10% de soro fetal bovino sob atmosfera com 5% de CO2 a 37ºC, e incubadas com diferentes concentrações de licopeno e beta-caroteno (0,5-5μM) por períodos de 48 e 96 horas. Para análise da proliferação celular foi utilizado o método do MTT. A análise por citometria de fluxo foi utilizada para avaliar a distribuição das fases de ciclo celular e apoptose. Resultados: mostraram que o licopeno diminuiu a proliferação celular da linhagem T84 após 96 horas de tratamento, com aumento de células na fase G1 e diminuição na fase G2/M, promovendo um aumento no processo de apoptose. Nenhum resultado foi observado em células tratadas com beta-caroteno. Conclusão: Diante dos resultados expostos, a quimioprevenção através da ação do licopeno emerge como um importante instrumento na prevenção e controle do câncer de cólon.</div
... The dietary and nutritional relevance of the tomato crop is evidenced by its high demand among both rural and urban populations [4]. It is a key component in the so-called "Mediterranean diet", which is strongly associated with reduced risk of chronic degenerative diseases [5], [6] Tomatoes are either consumed fresh or as processed . products such as canned tomato, sauce, juice ketchup, stews and soup [7], [8]. ...
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The antifungal potential of ethanolic leaf extracts of Vernonia amygdalina in the biological control of some common tomato wilt fungi was investigated. The experiment was set up in Completely Randomized Design (CRD) with eight treatments and three replicates. 5 mm diameter agar discs of 7 days old cultures of Fusarium oxysporum and Sclerotium rolfsii were obtained using a sterile 5 mm diameter cork borer and cultured on Potato Dextrose Agar (PDA) inoculated with 5 ml of various concentrations of V. amygdalina ethanolic leaf extracts in petri dishes, and incubated for 10 days at 28 0 C. The highest radial growth inhibitions of F. oxysporum (34.98%) and S. rolfsii (31.05%) were recorded 48 hours post-inoculation, both at 75% extract concentration. The leaf extracts of V. amygdalina used in the study exhibited significant inhibition of radial growth of the test organisms (P ≤ 0.05) and could be applied in the biological control of fungal wilt pathogens of tomato as a means of enhancing tomato yield and productivity.
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Tomato (Solanum lycopersicum) is one of the major vegetable plant and a model system for fruit development. Its global importance is due to its lycopene pigment which has anti-oxidative and anti-cancerous properties. Though > 1.5 M biotic stress associated ESTs of tomato are available but cumulative analysis to predict genes is warranted. Availability of whole genome de novo assembly can advantageously be used to map them over different chromosome. Further, available 0.14 M catalogued markers can be used to introgress specific desirable genes in varietal improvement program. We report here 57 novel genes associated with biotic stress of tomato along with 50 genes having physical location over different chromosomes. We also report 52 cis-regulating elements and 69 putative miRNAs which are involved in regulation of these biotic stresses associated genes. These putative candidate genes associated with biotic stress can be used in molecular breeding in the endeavor of tomato productivity along with its sustainable germplasm management.
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Phytochemicals derived from natural plants have been used commonly for the prevention and/or treatment of different diseases due to the belief of their safety. Many plant species synthesize toxic chemicals. New natural chemicals are being discovered but their toxic effects are unknown. Phytochemicals have been regarded as possible antioxidants. But on the other hand it is suggested that various phenolic antioxidants can display pro-oxidant properties at high doses. In this review, the role of some phytochemicals (epigallocathecin gallate, carvacrol, galangin, limonene, lycopene, naringin, puerarin, terpinene, thymol and ursolic acid) on the prevention of DNA damage will be discussed.
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Bitter melon aril is the tissue surrounding the seeds which turns into bright red when the melon is ripen. The ripe bitter melon aril could be an alternative source of nature lycopene for human consumption if proper extraction, purification, and formulation were applied. Ultrasonic extraction and reverse phase chromatography were employed to isolate and purify lycopene from the arils of bitter gourds. The concentration of lycopene increased from 13.6% in the extract obtained ultrasonically using hexane to 98.1% in the elution fraction that was obtained using an ethanol-to-acetone ratio of five to one. Then, the chromatographic purified lycopene was micronized using supercritical carbon dioxide anti-solvent (SAS) process. Under the best condition of SAS process tested in this study, ∼97% recovery of lycopene was achieved and the obtained particles were in the sub nanometer range with a flaky morphology. This study successfully proved that column fractionation coupled with SAS is a useful process to produce purified and micronized lycopene extracted from ripe bitter melon aril.
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Diet can play a major role in cancer prevention. The international differences in cancer incidence are largely accounted for by lifestyle practices that include nutrition, exercise, and alcohol and tobacco use. About 50% of cancer incidence and 35% of cancer mortality in the U.S., represented by cancers of the breast, prostate, pancreas, ovary, endometrium, and colon, are associated with Western dietary habits. Cancer of the stomach, currently a major disease in the Far East, relates to distinct, specific nutritional elements such as excessive salt intake. For these cancers, information is available on possible initiating genotoxic factors, promoting elements, and prophylactic agents. In general, the typical diet in the United States contains low levels of the potent carcinogenic agents, heterocyclic amines, formed during the cooking of meats. It provides only about half the potent appropriate fiber intake and is high in calories. About twice as many calories as would be desirable come from fat, certain kinds of which enhance the development of cancers. Other foods with functional properties, such as soy products and tea, can be beneficial. To achieve reduction in risk of certain cancers, diet must be optimized, primarily to reduce caloric intake and the fat component. The latter should be 20% or less of total caloric intake and fiber should be increased to 25-35 g per day for adults. One approach to achieving these goals is the Fiber First Diet, a diet designed around adequate fiber intake from grains, especially cereals, vegetables, legumes, and fruits, which thereby reduces both calorie and fat intake. Such dietary improvements will not only reduce cancer and other chronic disease risks, but will contribute to a healthy life to an advanced age. A corollary benefit is a lower cost of medical care.
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"Oxidative stress" is used as the generic term describing the involve­ ment of reactive oxygen species in various human diseases. The scope of such a topic is becoming increasingly wide. The recent interest in radicals such as nitric oxide and the discovery of new mechanisms such as the effect of free radicals on redox sensitive proteins and genes are enlarging our understanding of the physiological role of free radicals. Oxidative stress is involved in numerous pathological. processes such as ageing, respiratory or cardiovascular diseases, cancer, neurological pathologies such as dementia or Parkinson's disease. It still remains difficult, however, to demonstrate by chemical measurement the in vivo production of free radicals and even more to realise their speciation. Therefore, the development of new tools and indicators is engrossing many researchers working in this field. Reliable indicators are abso­ lutely necessary not only to monitor the evolution of oxidative stress in patients but also to evaluate the efficiency of new antioxidant treat­ ments. The French Free radical club of Grenoble, the CERLIB has been involved for many years in the organisation of international training programs on methodology, in order to provide both theoretical and practical help to researchers from various countries. Such training sessions have been highly successful and participants value the oppor­ tunity to learn reliable techniques. This positive echo explains why the researchers of CERLIB decided, with the help of Prof. Dr. B. Kalyanaraman, to publish selected techniques on free radical re­ search.
Book
This book serves as a comprehensive overview of the current scientific knowledge on the health effects of dietary and supplemental antioxidants (such as vitamins C and E). Chapters integrate information from basic research and animal studies, epidemiologic studies, and clinical intervention trials. The popular media has taken great interest in antioxidants, with numerous articles emphasizing their role in preventing disease and the possible slowing of the aging process. These antioxidant vitamins may be important in preventing not only acute deficiency symptoms, but also chronic disorders such as heart disease and certain types of cancer. This book, therefore, is not only for scientists and doctors, but also for health writers, journalists, and informed lay people. The text focuses on several human conditions for which there is now good scientific evidence that oxidation is an important etiological component. Specifically, antioxidants may prevent or slow down the progression of: Cancer, Cardiovascular disease, Immune system disorders, Cataracts, Neurological disorders, Degeneration due to the aging process.
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Consumption of tomatoes and tomato products has been shown to provide nutritional and health benefits.
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Cardiovascular disease is the number one cause of death in the United States. Cholesterollowering drugs and dietary and behavioral modifications have been the traditional choice of treatment for the disease. Recently, there has been an increased advocacy for the use of antioxidants to retard the progression of the disease. In this review, the role of oxidants in the promotion of cardiovascular disease and the means by which antioxidants may prevent the disease are outlined. Specifically, multiple pathways by which antioxidants may retard the progression of cardiovascular disease are described.