Cancer-protective factors in fruits and vegetables: biochemical and biological background

Antioxidant and hepatoprotective potential of Aegle marmelos Correa. against CCl4-induced oxidative stress and early tumor events

The antioxidant properties and inhibitory effect on early tumor promoter markers of A. marmelos (25 and 50 mg/Kg b. wt. orally) have been evaluated. Male Wistar rats were pre-treated for seven consecutive days with A. marmelos prior to CCl4 (1 mL Kg(- 1) body weight p. o., in corn oil [1:1 v/v]) treatment. Pre-treatment with A. marmelos suppressed lipid peroxidation (LPO), xanthine oxidase (XO) and release of serum toxicity marker enzymes viz, SGOT, LDH, SGPT dose-dependently and significantly (p < 0.001). Hepatic antioxidant status viz, reduced glutathione (GSH), glutathione reductase (GR), glutathione peroxidase (GPx), quinone reductase (QR), catalase (CAT) were concomitantly restored in A. marmelos-treated groups (p < 0.001). In addition, A. marmelos pretreatment also prevented the CCl4-enhanced ornithine decarboxylase (ODC) and hepatic DNA synthesis significantly (p < 0.001). In conclusion, carbon tetrachloride-induced liver toxicity was strikingly attenuated by A. marmelos treatment and the study gives some insight into the mechanisms involved in diminution of free radical generating toxicants and enhancement of the antioxidant armory, hence preventing further tissue damage, injury and hyperproliferation. Thus, these findings indicate that A. marmelos attenuates CCl4-mediated hepatic oxidative stress, toxicity, tumor promotion and subsequent cell proliferation response in Wistar rats.

Nutritional and functional properties of dates: a review

This review article provides information on the nutritional and functional constituents of dates (Phoenix dactylifera L.) and their seeds from over 80 references. Date flesh is found to be low in fat and protein but rich in sugars, mainly fructose and glucose. It is a high source of energy, as 100 g of flesh can provide an average of 314 kcal. Ten minerals were reported, the major being selenium, copper, potassium, and magnesium. The consumption of 100 g of dates can provide over 15% of the recommended daily allowance from these minerals. Vitamins B-complex and C are the major vitamins in dates. High in dietary fiber (8.0 g/100 g), insoluble dietary fiber was the major fraction of dietary fiber in dates. Dates are a good source of antioxidants, mainly carotenoids and phenolics. Date seeds contain higher protein (5.1 g/100 g) and fat (9.0 g/100 g) as compared to the flesh. It is also high in dietary fiber (73.1 g/100 g), phenolics (3942 mg/100 g) and antioxidants (80400 micromol/100 g). This detailed information on nutritional and health promoting components of dates and their seeds will enhance our knowledge and appreciation for the use of dates in our daily diet and their seeds as a functional food ingredient.

Duchesnea phenolic fraction inhibits in vitro and in vivo growth of cervical cancer through induction of apoptosis and cell cycle arrest

Duchesnea indica (Andr.) Focke has been commonly used to treat cancer in Asian countries for centuries, and recently has been shown to possess anticancer properties in vitro and in vivo. But the underlying mechanism of the anticancer action is unclear, especially in in vivo studies. In this study, we investigated the anticancer effect and associated mechanisms of Duchesnea phenolic fraction (DPF) on cervical cancer in vitro and in vivo. Our results showed that DPF significantly inhibited cervical cancer cell proliferation in dose- and time-dependent manners. DPF induced apoptosis as determined by AO/EB staining, DNA fragmentation and flow cytometry. Some apoptosis correlated proteins were altered following DPF treatment. Bax was up-regulated while Bcl-2 was down-regulated, and the expression ratio of Bax/Bcl-2 was increased. These resulted in the translocation of Bax to mitochondria, the release of cytochrome c from the mitochondria to the cytosol and caspase-3 activation. Concurrently, DPF provoked S phase arrest along with significant down-regulation of S phase-associated proteins, such as cyclin A, cyclin E, cyclin D1 and cdk2. Transplanted U14 cervical cancer mouse model was used to evaluate the antitumor effect of DPF in vivo. Compared with control, DPF treatment markedly prolonged survival of tumor-bearing mice and dose-dependently reduced the tumor weight. DPF could induce apoptosis in tumor tissues as evidenced by increased TUNEL-positive cells, activation of caspase-3, up-regulation of Bax and down-regulation of Bcl-2. In addition, DPF significantly decreased the expression of cell proliferation markers PCNA and ki67 in tumors. All together, these data sustain our contention that DPF has anticancer properties and merits further investigation as a potential therapeutic agent.

Cytoprotective effect of mangiferin on benzo(a)pyrene-induced lung carcinogenesis in swiss albino mice

Antioxidants are one of the key players in tumourigenesis, and several natural and synthetic antioxidants have been shown to have anticancer effects. In the present investigation, the efficacy of mangiferin on the antioxidant status of benzo(a)pyrene-induced lung carcinogenesis in Swiss albino mice was assessed. The animals were divided into five groups. The animals in groups I and V were normal control and mangiferin control, respectively. Groups II, III and IV were administered with benzo(a)pyrene (50 mg/kg body weight, orally) for 4 weeks (twice a week) to induced lung carcinogenesis. Starting 1 week prior to benzo(a)pyrene administration, group III animals were treated with mangiferin (100 mg/kg body weight) in the diet for 18 weeks; 12 weeks after benzo(a)pyrene administration, group III animals were treated with mangiferin that continued until the end of the experiment period (18 weeks). At the end of the experiment period, the reactive oxygen species, glutathione and the activities of antioxidant enzymes were assessed in both lung and liver tissues. The levels of glutathione, superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, vitamin E and vitamin C were decreased in group II animals. However, in the mangiferin + benzo(a)pyrene-treated groups III and IV, the levels of GSH and the activities of antioxidant enzymes in both lung and liver were improved when compared with benzo(a)pyrene-induced group II animals. In addition, the finding that mangiferin decreased reactive oxygen species levels and enhanced antioxidant status suggests that this polyphenol might also be of value in the prevention of benzo(a)pyrene-induced lung carcinogenesis.

Reducing human exposure to aflatoxin through the use of clay: a review

Innovative sorption strategies for the detoxification of aflatoxins have been developed. NovaSil clay (NS) has been shown to prevent aflatoxicosis in a variety of animals when included in their diet. Results have shown that NS clay binds aflatoxins with high affinity and high capacity in the gastrointestinal tract, resulting in a notable reduction in the bioavailability of these toxins without interfering with the utilization of vitamins and other micronutrients. This strategy is being evaluated as a potential remedy for acute aflatoxicosis, and as a sustainable human intervention for aflatoxins via the diet. Phase I and II clinical trials confirmed the apparent safety of NS for further study in humans. A recent study in Ghanaians at high risk for aflatoxicosis has indicated that NS (at a dose level of 0.25%) is effective in decreasing biomarkers of aflatoxin exposure and does not interfere with the levels of serum vitamins A and E, and iron and zinc. In summary, enterosorption strategies/therapies based on NS clay are promising for the management of aflatoxins and as a sustainable public health intervention. The NS clay remedy is novel, inexpensive and easily disseminated. Based on the present research, aflatoxin sequestering clays should be rigorously evaluated in vitro and in vivo, and should meet the following criteria: (1) favourable thermodynamic characteristics of mycotoxin sorption, (2) tolerable levels of priority metals, dioxins/furans and other hazardous contaminants, (3) safety and efficacy in multiple animal species, (4) safety and efficacy in long-term studies, and (5) negligible interactions with vitamins, iron and zinc and other micronutrients.

Role of transglutaminase 2 in quercetin-induced differentiation of B16-F10 murine melanoma cells

Flavonoids belong to the class of plant polyphenolic compounds with over 6,000 individual structures known. These phytochemicals have attracted the interest of the scientists, because they possess a remarkable spectrum of biological activities, such as antiallergic, antiinflammatory, antioxidant, antimutagenic and anticarcinogenic. In this work, we compared the anticancer potential of two flavonoids, quercetin and pelargonidin, on highly metastatic B16-F10 melanoma murine cells. We have evaluated different parameters related to cell proliferation and differentiation, such as cell number, toxicity, intracellular content of polyamines and transglutaminase (TG, EC 2.3.2.13) activity. The higher inhibition of tumor cell growth, with respect to control, was obtained with quercetin cell treatment, i.e. 32% reduction after 48 h and 39% reduction after 72 h of incubation (P < 0.001). In parallel, quercetin-treated cells showed a similar decrease in polyamine content. TG activity was fourfold increased, with respect to control, after 48 h and twofold increased after 72 h (P < 0.001). Pelargonidin treatment did not show significant antiproliferative effects and any increase in TG activity. Proteomic approach was used to investigate changes in protein expression profiles in tumor cells following quercetin treatment. Changes in expression of 60 proteins were detected, i.e. 8 proteins were down-regulated, 35 up-regulated, 11 "de novo" synthetized proteins and 6 suppressed proteins were present in treated cells. A 80 kDa spot, identified as TG type 2 by Western blot analysis, presented a fourfold increase in intensity, confirming the key role played by TG in the induction of cancer cell differentiation.

Consumption of vegetables alters morning urinary 6-sulfatoxymelatonin concentration

Melatonin, which is contained in certain vegetables, may have an influence on circulatory melatonin concentrations. This study examined the effects of the consumption of vegetables on 6-sulfatoxymelatonin concentrations in morning urine. Ninety-four healthy women aged 24-55 were recruited through a city public health center in Japan. The women randomly allocated to the intervention group were requested to consume high amounts of six selected vegetables, with a target of 350 g/day for 65 days, while those in the control group were asked to avoid the same six vegetables during the same period. First-void morning urine was collected before and at the end of the intervention period, and creatinine-adjusted 6-sulfatoxymelatonin concentrations were measured. At the end of the intervention period, daily mean intake of melatonin from the six vegetables was 1288.0 ng in the intervention group and 5.3 ng in the control group. In the intervention group, the mean concentration of 6-sulfatoxymelatonin changed from 48.1 [95% confidence interval (CI): 40.4-57.2] ng/mg creatinine to 49.6 (95% CI: 42.8-57.3) ng/mg creatinine across the intervention period. In the control group, the mean concentration of 6-sulfatoxymelatonin changed from 55.5 (95% CI: 48.7-63.2) ng/mg creatinine to 50.8 (95% CI: 44.0-58.7) ng/mg creatinine across the intervention period. A comparison of the two groups with regard to the changes in the 6-sulfatoxymelatonin concentrations across the intervention period showed a significant difference (P = 0.03). The results indicate that increased consumption of vegetables raises circulatory melatonin concentrations.

Mechanisms of colorectal and lung cancer prevention by vegetables: a genomic approach

Colorectal cancer (CRC) and lung cancer (LC) occur at high incidence, and both can be effectively prevented by dietary vegetable consumption. This makes these two types of cancer highly suitable for elucidating the underlying molecular mechanisms of cancer chemoprevention. Numerous studies have shown that vegetables exert their beneficial effects through various different mechanisms, but effects on the genome level remain mostly unclear. This review evaluates current knowledge on the mechanisms of CRC and LC prevention by vegetables, thereby focusing on the modulation of gene and protein expressions. The majority of the effects found in the colon are changes in the expression of genes and proteins involved in apoptosis, cell cycle, cell proliferation and intracellular defense, in favor of reduced CRC risk. Furthermore, vegetables and vegetable components changed the expression of many more genes and proteins involved in other pathways for which biologic meaning is less clear. The number of studies investigating gene and protein expression changes in the lungs is limited to only a few in vitro and animal studies. Data from these studies show that mostly genes involved in biotransformation, apoptosis and cell cycle regulation are affected. In both colon and lungs, genomewide analyses of gene and protein expression changes by new genomics and proteomics technologies, as well as the investigation of whole vegetables, are few in number. Further studies applying these 'omics' approaches are needed to provide more insights on affected genetic/biologic pathways and, thus, in molecular mechanisms by which different chemopreventive compounds can protect against carcinogenesis. Particularly studies with combinations of phytochemicals and whole vegetables are needed to establish gene expression changes in the colon, but especially in the lungs.

Low-dose dietary chlorophyll inhibits multi-organ carcinogenesis in the rainbow trout

We recently reported that chlorophyll (Chl) strongly inhibits aflatoxin B(1) preneoplasia biomarkers in rats when administered by co-gavage (Simonich et al., 2007. Natural chlorophyll inhibits aflatoxin B1-induced multi-organ carcinogenesis in the rat. Carcinogenesis 28, 1294-1302.). The present study extends this by examining the effects of dietary Chl on tumor development, using rainbow trout to explore ubiquity of mechanism. Duplicate groups of 140 trout were fed diet containing 224 ppm dibenzo[a,l]pyrene (DBP) alone, or with 1000-6000 ppm Chl, for 4 weeks. DBP induced high tumor incidences in liver (51%) and stomach (56%), whereas Chl co-fed at 2000, 4000 or 6000 ppm reduced incidences in stomach (to 29%, 23% and 19%, resp., P<0.005) and liver (to 21%, 28% and 26%, resp., P<0.0005). Chlorophyllin (CHL) at 2000 ppm gave similar protection. Chl complexed with DBP in vitro (2Chl:DBP, K(d1)=4.44+/-0.46 microM, K(d2)=3.30+/-0.18 microM), as did CHL (K(d1)=1.38+/-0.32 microM, K(d2)=1.17+/-0.05 microM), possibly explaining their ability to inhibit DBP uptake into the liver by 61-63% (P<0.001). This is the first demonstration that dietary Chl can reduce tumorigenesis in any whole animal model, and that it may do so by a simple, species-independent mechanism.

Suppression of human ovarian SKOV-3 cancer cell growth by Duchesnea phenolic fraction is associated with cell cycle arrest and apoptosis

OBJECTIVE

Duchesnea indica (Andr.) Focke has been commonly used to treat cancer in Asian countries of centuries, and more recently, has been shown to possess anticancer properties in vivo and in vitro. However, little is known about the underlying mechanism of its anticancer action. In the present study, we investigated the effect of Duchesnea phenolic fraction (DPF) on SKOV-3 ovarian cancer cells to provide insights into the mechanisms of growth suppression involved in DPF-mediated apoptosis and cell cycle arrest.

METHODS

Cytotoxic activity of DPF on SKOV-3 cells was determined using MTT assay, apoptosis (AO/EB staining, DNA fragmentation, FACS), caspase-3 activation and cell cycle analysis studies. The role of the molecules in apoptosis and cell cycle regulation was analyzed by Western blot and RT-PCR.

RESULTS

DPF significantly inhibited SKOV-3 cell proliferation in a dose-dependent manner and markedly induced apoptosis evidenced by characteristic apoptotic morphological changes, nuclear DNA fragmentation and sub-G1 peak. DPF suppressed Bcl-2 levels, enhanced Bax levels and Bax/Bcl-2 ratio, and simultaneously translocated Bax to mitochondria followed by mitochondrial release of cytochrome c into the cytosol and activation of effector caspase-3. Furthermore, DPF provoked S phase arrest in SKOV-3 cells with down-regulation of cyclin A, E, D1 and CDK2.

CONCLUSION

DPF exhibits cytotoxicity towards human ovarian cancer SKOV-3 cells through induction of apoptosis via mitochondrial pathway and arresting cell cycle progression in S phase. All together, these data sustain our contention that DPF has anticancer properties and merits further investigation as a potential therapeutic agent.

Discriminative protection against hydroxyl and superoxide anion radicals by quercetin in human leucocytes in vitro

Antioxidants play a vital role in the cellular protection against oxidative damage. Quercetin is a well-investigated antioxidant and known to be able to protect against cellular oxidative DNA damage. In this study, we tried to relate the protection by quercetin pre-treatment against oxidative DNA damage in human leucocytes in vitro to the interaction of quercetin in solution with hydroxyl and superoxide anion radicals as measured by electron spin resonance (ESR) spectrometry, using DMPO as a spin trap. Further, scavenging capacity of quercetin-treated leucocytes in vitro was evaluated by ESR spectrometry. Quercetin appears capable of protecting human leucocytes against oxidative DNA damage caused by hydrogen peroxide in a dose-dependent manner. The protection of leucocytes against superoxides is ambiguous. Incubation concentrations of quercetin (1, 10, and 50 microM) reduced levels of superoxide-induced oxidative DNA damage, while at 100 microM the amount of damage was increased. These results are supported by ESR-findings on quercetin in solution, also showing a prooxidant effect at 100 microM. ESR spectroscopy showed rate constant values for the reaction kinetics of quercetin in lowering iron-dependent hydroxyl radical formation and NADH-dependent superoxide anion formation of respectively 3.2 x 10(12)M(-1)s(-1) and 1.1 x 10(4)M(-1)s(-1). This shows that quercetin is a more potent inhibitor of hydroxyl radical formation than a scavenger of superoxide anions.

NovaSil clay intervention in Ghanaians at high risk for aflatoxicosis. I. Study design and clinical outcomes

A 3-month double-blind and placebo-controlled, phase IIa clinical trial was conducted in Ghana to investigate the safety, tolerance and aflatoxin-sorption efficacy of dietary NovaSil (NS). Volunteers (507 subjects) were clinically screened to evaluate their general health, pregnancy status and blood AFB(1)-albumin adduct levels. Of these subjects, 177 were randomly assigned to three groups: high-dose (HD), low-dose (LD) and placebo-control (PL) groups receiving 3.0, 1.5 and 0 g NS day(-1) in capsules. Trained study-monitors supervised NS capsule administration to participants and recorded side-effects daily. Physical examinations were performed monthly. Blood and urine samples were collected for laboratory analysis. Approximately 92% of the participants (162 of 177) completed the study and compliance rate was over 97%. Overall, 99.5% of person x time reported no side-effects throughout the study. Mild to moderate health events ( approximately 0.5% of person x time) were recorded in some participants. Symptoms included nausea, diarrhea, heartburn and dizziness. These side-effects were statistically similar among all three groups. No significant differences were shown in hematology, liver and kidney function or electrolytes in the three groups. These findings demonstrate that NS clay is apparently safe and practical for the protection of humans against aflatoxins in populations at high risk for aflatoxicosis.

Impact of multiple genetic polymorphisms on effects of a 4-week blueberry juice intervention on ex vivo induced lymphocytic DNA damage in human volunteers

Consumption of fruits and vegetables has been associated with a decrease in cancer incidence and cardiovascular disease, presumably caused by antioxidants. We designed a human intervention study to assess antioxidative and possible anti-genotoxic properties of fruit-borne antioxidants. We hypothesized that individuals bearing genetic polymorphisms for genes related to quercetin metabolism, benzo[a]pyrene metabolism, oxidative stress and DNA repair differ in their response to DNA protective effects of increased antioxidant intake. In the present study, 168 healthy volunteers consumed a blueberry/apple juice that provided 97 mg quercetin and 16 mg ascorbic acid a day. After a 4-week intervention period, plasma concentrations of quercetin and ascorbic acid and trolox equivalent antioxidant capacity (TEAC) were significantly increased. Further, we found 20% protection (P < 0.01) against ex vivo H(2)O(2)-provoked oxidative DNA damage, measured by comet assay. However, the level of ex vivo induced benzo[a]pyrene-diol-epoxide (BPDE)-DNA adducts was 28% increased upon intervention (P < 0.01). Statistical analysis of 34 biologically relevant genetic polymorphisms revealed that six significantly influenced the outcome of the intervention. Lymphocytes from individuals bearing variant genotype for Cyp1B1 5 seemed to benefit more than wild-types from DNA damage-protecting effects upon intervention. Variants for COMT tended to benefit less or even experienced detrimental effects from intervention. With respect to GSTT1, the effect is ambiguous; variants respond better in terms of intervention-related increase in TEAC, but wild-types benefit more from its protecting effects against oxidative DNA damage. We conclude that genotyping for relevant polymorphisms enables selecting subgroups among the general population that benefit more of DNA damage-modulating effects of micronutrients.

Expression of DNA repair and metabolic genes in response to a flavonoid-rich diet

A diet rich in fruit and vegetables can be effective in the reduction of oxidative stress, through the antioxidant effects of phytochemicals and other mechanisms. Protection against the carcinogenic effects of chemicals may also be exerted by an enhancement of detoxification and DNA damage repair mechanisms. To investigate a putative effect of flavonoids, a class of polyphenols, on the regulation of the gene expression of DNA repair and metabolic genes, a 1-month flavonoid-rich diet was administered to thirty healthy male smokers, nine of whom underwent gene expression analysis. We postulated that tobacco smoke is a powerful source of reactive oxygen species. The expression level of twelve genes (APEX, ERCC1, ERCC2, ERCC4, MGMT, OGG1, XPA, XPC, XRCC1, XRCC3, AHR, CYP1A1) was investigated. We found a significant increase (P < 0.001) in flavonoid intake. Urinary phenolic content and anti-mutagenicity did not significantly change after diet, nor was a correlation found between flavonoid intake and urinary phenolic levels or anti-mutagenicity. Phenolic levels showed a significant positive correlation with urinary anti-mutagenicity. AHR levels were significantly reduced after the diet (P = 0.038), whereas the other genes showed a generalized up regulation, significant for XRCC3 gene (P = 0.038). Also in the context of a generalized up regulation of DNA repair genes, we found a non-significant negative correlation between flavonoid intake and the expression of all the DNA repair genes. Larger studies are needed to clarify the possible effects of flavonoids in vivo; our preliminary results could help to better plan new studies on gene expression and diet.

Carbohydrate Digestibility Predicts Colon Carcinogenesis in Azoxymethane-Treated Rats

The purpose of this study was to compare the effect of carbohydrate structure and digestibility on azoxymethane (AOM)-induced colon carcinogenesis. Five groups of male Fischer 344 rats each comprising 30 animals were injected with AOM and fed a high-fat diet with 15% of various carbohydrates. The carbohydrate sources used were sucrose, cornstarch (a linear starch, reference group), potato starch (a branched starch), a short-chained oligofructose (Raftilose), and a long-chained inulin-type fructan (Raftiline). An interim sacrifice was performed after 9 wk to investigate markers of carbohydrate digestibility, including caecal fermentation (caecum weight and pH) and glucose and lipid metabolism [glucose, fructoseamine, HbA1c, triglycerides, and insulin-like growth factor (IGF) 1]. In addition potential early predictors of carcinogenicity [cell proliferation and aberrant crypt foci (ACF)] at 9 wk and their correlation to colon cancer risk after 32 wk were investigated. Tumor incidence was significantly reduced in animals fed oligofructose, and the number of tumors per animal was significantly reduced in animals fed inulin and oligofructose at 32 wk after AOM induction compared to the reference group fed sucrose. Increased caecum weight and decreased caecal pH were seen in groups fed oligofructose, inulin, and potato starch. Plasma triglyceride was decreased in rats fed oligofructose and inulin. Cell proliferation was increased in the proximal colon of rats fed sucrose, oligofructose, and inulin, and the number of cells per crypt decreased in rats fed oligofructose and inulin. The total number of ACF's was unaffected by treatment, and the size and multiplicity of ACF was unrelated to tumor development. It was concluded that less digestible carbohydrates with an early effect on caecum fermentation and plasma triglyceride decreased subsequent tumor incidence and multiplicity. This was unrelated to ACF, cell proliferation, and other markers of glucose and lipid metabolism.

Aqueous Vernomia amygdalina extracts alter MCF-7 cell membrane permeability and efflux

Breast cancer is the second leading cause of cancer related deaths of women in the United States. Several treatment strategies have been developed over the past decade to reduce cancer morbidity and mortality rates. While mortality rates have declined in some ethnic populations, the overall cancer incidence continues to grow. Hence, chemotherapeutic agents are needed to improve cancer treatment outcome. Previous studies show that low concentrations (microgram/ml) of water-soluble leaf extracts of a Nigerian edible plant, V. amygdalina (VA), potently retard the proliferative activities of estrogen receptor positive (ER+) human breast cancerous cells (MCF-7) cells in vitro in a concentration-dependent fashion. The anti-proliferative activities of VA are extracellular signal-regulated kinases (1/2) (ERKs (1/2))-dependent. Cell culture and animal model studies, conducted by other investigators using other plant extracts, have also revealed that plant extract components called thionins may be responsible for their anticancer activities. These thionins are believed to interact with the cells in ways that compromise membrane potential/permeability resulting in the alteration of efflux, cytosolic activities, and subsequent cell death. Therefore, we hypothesized that VA exposure may compromise cell membrane as another mode of action to elicit its anticancer activities in MCF-7 cells. The exposure of cells to VA decreased [3H]thymidine uptake in a concentration-dependent (0, 30, and 100 mug/ml VA) manner (p < 0.05) but increased [3H]thymidine release, expressed as percent of [3H]thymidine incorporated, into the medium (p < 0.05). The amount of [3H]thymidine released into the medium was 1.7, 7.4, and 11.0 % for 0, 30, and 100 mug/ml VA respectively. Thus suggesting the membranes in VA-treated cells were compromised in a concentration-dependent fashion.

Biological effects of fruit and vegetables

A strong and persistent effect of plant-derived foods on the prevention of lifestyle diseases has emerged from observational studies. Several groups of constituents in plants have been identified as potentially health promoting in animal studies, including cholesterol-lowering factors, antioxidants, enzyme inducers, apoptosis inducers etc. In human intervention studies the dose levels achieved tend to be lower than the levels found to be effective in animals and sampling from target organs is often not possible. A controlled dietary human intervention study was performed with forty-three volunteers, providing 600 g fruit and vegetables/d or in the controls a carbohydrate-rich drink to balance energy intake. Surrogate markers of oxidative damage to DNA, protein and lipids, enzymic defence and lipid metabolism were determined in blood and urine. It was found that a high intake of fruit and vegetables tends to increase the stability of lipids towards oxidative damage. Markers of oxidative enzymes indicate a steady increase in glutathione peroxidase (GPX1) activity in erythrocytes during intervention with fruit and vegetables but there is no effect on GPX1 transcription levels in leucocytes. No change occurs in glutathione-conjugating or -reducing enzyme activities in erythrocytes or plasma, and there are no effects on the transcription of genes involved in phase 2 enzyme induction or DNA repair in leucocytes. Fruit and vegetable intake decreases the level of total cholesterol and LDL-cholesterol, but does not affect sex hormones. In conclusion, it has been shown that total cholesterol and LDL-cholesterol, markers of peripheral lipid oxidation, and erythrocyte GPX1 activity are affected by high intakes of fruit and vegetables. This finding provides support for a protective role of dietary fruit and vegetables against CVD.

Correlates between vegetable consumption and gallbladder cancer

The results of several studies indicate that a diet rich in fresh vegetables protects against several common epithelial neoplasms. This probable effect has been related to specific micronutrients contained in vegetables. In the present case-control study a systematic assessment of the relationship between vegetable intake and the risk of gallbladder cancer has been undertaken. The study is of particular interest in order to better understand the quantifying effect of vegetable consumption with regard to gallbladder cancer. One hundred and fifty-three patients with gallbladder cancer and 153 controls with gallstone disease were included. Each patient's consumption of vegetables was assessed by using a food frequency questionnaire. The frequency of vegetable consumption was divided into three levels: > or =3 days/week, 1-2 days/week and no or rare consumption. Participants were divided into three groups according to the level of vegetable intake. Odds ratios and 95% confidence intervals were computed for subsequent levels of vegetable consumption compared with the high level of consumption. A low consumption of vegetables showed an increase in odds ratio for gallbladder cancer for almost all the vegetables studied. A significant inverse trend was observed for green leafy vegetables and gallbladder cancer. An inverse association was observed for amaranth with an OR of 3.45 for the low vs. high level of consumption. Corresponding values were 2.14 for spinach, 1.86 for bathua, 1.02 for bengalgram leaves, 2.26 for cabbage, 3.06 for fenugreek leaves, 1.95 for mustard leaves and 1.44 for radish leaves. An inverse relationship between the risk of gallbladder cancer and the level of vegetable consumption was observed.

Induction of apoptosis and cell cycle arrest by a chalcone panduratin A isolated from Kaempferia pandurata in androgen-independent human prostate cancer cells PC3 and DU145

Because of unsatisfactory treatment options for prostate cancer (CaP) there is a need to develop novel preventive approaches for this malignancy. One such strategy is through chemoprevention by the use of non-toxic dietary substances and botanical products. We have shown previously that panduratin A isolated from the extract of Kaempferia pandurata (Zingiberaceae) is a strong inhibitor of cyclooxygenase-2 in RAW264.7 cells and induces apoptosis in HT-29 cells. In the present study, we provide evidence that panduratin A treatment to androgen-independent human CaP cells PC3 and DU145 result in a time and dose-dependent inhibition of cell growth with an IC50 of 13.5-14 microM and no to little effect on normal human prostate epithelial cells. To define the mechanism of these anti-proliferative effects of panduratin A, we determined its effect on critical molecular events known to regulate the cell cycle and the apoptotic machinery. Annexin V/propidium iodide staining provided the evidence for the induction of apoptosis which was further confirmed by the observation of cleavage of poly (ADP-ribose) polymerase and degradation of acinus. Panduratin A treatment to cells was found to result in inhibition of procaspases 9, 8, 6 and 3 with significant increase in the ratio of Bax:Bcl-2, suggesting the involvement of a mitochondrial-dependent apoptotic pathway. Panduratin A-mediated apoptosis was accompanied with upregulation of Fas death receptor and TNF-related apoptosis-inducing ligand (TRAIL). Furthermore, cell cycle analysis using flow cytometry showed that panduratin A treatment of cells resulted in a G2/M arrest in a dose-dependent manner. The immunoblot analysis data revealed that in both cell lines panduratin A treatment resulted in a dose-dependent (i) induction of p21WAF1/Cip1 and p27Kip1, (ii) downregulation of cdks 2, 4 and 6 and (iii) decrease in cyclins D1 and E. These findings suggest that panduratin A may be an effective chemopreventive or therapeutic agent against CaP.

Association of vegetable intake with urinary 6-sulfatoxymelatonin level

Melatonin is present in plants consumed as vegetables; however, only a limited number of vegetables have been tested for melatonin. The antiproliferative, antioxidative, and immunostimulatory effects of melatonin have been reported from laboratory studies. The potential protective effects of vegetable against cancer and cardiovascular disease may be partially attributable to an increased melatonin intake from vegetables. As a first step to test this hypothesis, we evaluated whether vegetable intake is associated with an increased urinary melatonin in 289 community-dwelling Japanese women. Diet, including vegetable consumption, was assessed with a validated 169-item semiquantitative food-frequency questionnaire. Urinary 6-sulfatoxymelatonin (aMT6-s) was measured in the first-void morning urines. There was a significant positive association between vegetable intake and urinary aMT6-s levels. The mean urinary aMT6-s was 16% higher in women with the highest quartile of vegetable intake than it was in those with the lowest quartile of intake. This association may be explained by the melatonin contained in vegetables. However, data should be regarded as preliminary because it is impossible to estimate dietary melatonin intake from vegetables and or from the entire diet because of incomplete data for melatonin in plants.

The antioxidant effect of tannic acid on the in vitro copper-mediated formation of free radicals

Tannic acid (TA) has well-described antimutagenic and antioxidant activities. The antioxidant activity of TA has been previously attributed to its capacity to form a complex with iron ions, interfering with the Fenton reaction [Biochim. Biophys. Acta 1472, 1999, 142]. In this work, we observed that TA inhibits, in the micromolar range, in vitro Cu(II) plus ascorbate-mediated hydroxyl radical (*OH) formation (determined as 2-deoxyribose degradation) and oxygen uptake, as well as copper-mediated ascorbate oxidation and ascorbate radical formation (quantified in EPR studies). The effect of TA against 2-deoxyribose degradation was three orders of magnitude higher than classic *OH scavengers, but was similar to several other metal chelators. Moreover, the inhibitory effectiveness of TA, by the four techniques used herein, was inversely proportional to the Cu(II) concentration in the media. These results and the observation of copper-induced changes in the UV spectra of TA are indications that the antioxidant activity of TA relates to its copper chelating ability. Thus, copper ions complexed to TA are less capable of inducing ascorbate oxidation, inhibiting the sequence of reactions that lead to 2-deoxyribose degradation. On the other hand, the efficiency of TA against 2-deoxyribose degradation declined considerably with increasing concentrations of the *OH detector molecule, 2-deoxyribose, suggesting that the copper-TA complex also possesses an *OH trapping activity.

Protection by quercetin and quercetin-rich fruit juice against induction of oxidative DNA damage and formation of BPDE-DNA adducts in human lymphocytes

Flavonoids are claimed to protect against cardiovascular disease, certain forms of cancer and ageing, possibly by preventing initial DNA damage. Therefore, we investigated the protective effects of the flavonoid quercetin against the formation of oxidative DNA damage and bulky DNA adducts in human lymphocytes, both in vitro and ex vivo. First, human lymphocytes were pre-incubated with various concentrations of quercetin, followed by incubation with hydrogen peroxide; protection against oxidative DNA damage was evaluated by use of the single-cell gel electrophoresis (Comet) assay. Second, quercetin-treated human lymphocytes were challenged by treatment with benzo(a)pyrene (B(a)P), and BPDE-DNA adduct formation was measured by (32)P-postlabelling. Third, in a pilot study, lymphocytes from female volunteers who consumed a quercetin-rich blueberry/apple juice mixture for four weeks, were treated ex vivo with an effective dose of H(2)O(2) and benzo(a)pyrene, respectively, at three different time points, i.e. before (t=0 weeks), during (t=2 weeks) and after (t=4 weeks) the intervention. Results in vitro: a significant dose-dependent protection by quercetin against both the formation of oxidative DNA damage (p<0.01) and of BPDE-DNA adducts (p<0.05) was observed. Results in vivo: four weeks of juice intervention led to a significant increase in the total antioxidant capacity of plasma, as reflected by the increase of the TEAC value from 773 microM trolox equivalent at t=0 to 855 microM at t=4 weeks (p=0.04) and an increase in plasma quercetin content from 5.0 to 10.6 nM (p=0.03). After intervention, the level of oxidative damage upon ex vivo exposure to H(2)O(2) was non-significantly (p=0.07) decreased by 41%, and the BPDE-DNA adduct level induced ex vivo was non-significantly decreased by 11%. The combination of our findings in vitro and ex vivo provides evidence that quercetin is able to protect against chemically induced DNA damage in human lymphocytes, which may underlie its suggested anticarcinogenic properties.

Human serum albumin complexes with chlorophyll and chlorophyllin

Porphyrins and their metal derivatives are strong protein binders. Some of these compounds have been used for radiation sensitization therapy of cancer and are targeted to interact with cellular DNA and protein. The presence of several high-affinity binding sites on human serum albumin (HSA) makes it possible target for many organic and inorganic molecules. Chlorophyll a and chlorophyllin (a food-grade derivative of chlorophyll), the ubiquitous green plant pigment widely consumed by humans, are potent inhibitors of experimental carcinogenesis and interact with protein and DNA in many ways. This study was designed to examine the interaction of HSA with chlorophyll (Chl) and chlorophyllin (Chln) in aqueous solution at physiological conditions. Fourier transform infrared, UV-visible, and CD spectroscopic methods were used to determine the pigment binding mode, the binding constant, and the effects of porphyrin complexation on protein secondary structure. Spectroscopic results showed that chlorophyll and chlorophyllin are located along the polypeptide chains with no specific interaction. Stronger protein association was observed for Chl than for Chln, with overall binding constants of K(Chl) = 2.9 x 10(4)M(-1) and K(Chln) = 7.0 x 10(3)M(-1). The protein conformation was altered (infrared data) with reduction of alpha-helix from 55% (free HSA) to 41-40% and increase of beta-structure from 22% (free HSA) to 29-35% in the pigment-protein complexes. Using the CDSSTR program (CD data) also showed major reduction of alpha-helix from 66% (free HSA) to 58 and 55% upon complexation with Chl and Chln, respectively.

Aegle marmelos (L.) CORREA Inhibits the Proliferation of Transplanted Ehrlich Ascites Carcinoma in Mice

The anticancer effect of hydroalcoholic extract of Aegle marmelos (AME) was studied in the Ehrlich ascites carcinoma bearing Swiss albino mice. The spatial effect of various AME administration schedules showed that six-day administration increased the survival of tumor bearing mice. The best antineoplastic action of AME was obtained when AME administered through intraperitoneal route than the oral route at equimolar dose. Administration of AME once daily for six consecutive days to the tumor bearing mice caused a dose dependent remission of the tumor at 400 mg/kg body weight, where the greatest antitumor effect was observed and the higher doses showed toxic manifestations. A 24-d lengthening in life span was observed in EAC animals treated with 400 mg/kg AME. This dose of 400 mg/kg was considered as the best dose, where the animals survived up to 43 d post-tumor-cell inoculation as against no survivors in the saline treated control group. The antitumor activity when tested for different schedules for triple administrations, the best effect was observed for 1-2-3, followed by 1-3-5 and 1-5-9 days, respectively. Stage specific evaluation of AME inhibited the increase in body weight gain in animals due to tumor development during early stages only. The AME treatment resulted in a dose dependent elevation in the median survival time (MST) and average survival time (AST) up to 400 mg/kg AME and decline thereafter. The effective dose of 400 mg of AME is 1/6th of the LD50 dose, which increased the MST and AST up to 29 and 27 d, respectively. The acute toxicity study of AME showed that the drug was non-toxic up to a dose of 1750 mg/kg b. wt. The LD10 and LD50 was found to be 2000 and 2250 mg/kg.

Potential synergy of phytochemicals in cancer prevention: mechanism of action

Epidemiological studies have consistently shown that regular consumption of fruits and vegetables is strongly associated with reduced risk of developing chronic diseases, such as cancer and cardiovascular disease. It is now widely believed that the actions of the antioxidant nutrients alone do not explain the observed health benefits of diets rich in fruits and vegetables, because taken alone, the individual antioxidants studied in clinical trials do not appear to have consistent preventive effects. Work performed by our group and others has shown that fruits and vegetable phytochemical extracts exhibit strong antioxidant and antiproliferative activities and that the major part of total antioxidant activity is from the combination of phytochemicals. We proposed that the additive and synergistic effects of phytochemicals in fruits and vegetables are responsible for these potent antioxidant and anticancer activities and that the benefit of a diet rich in fruits and vegetables is attributed to the complex mixture of phytochemicals present in whole foods. This explains why no single antioxidant can replace the combination of natural phytochemicals in fruits and vegetables to achieve the health benefits. The evidence suggests that antioxidants or bioactive compounds are best acquired through whole-food consumption, not from expensive dietary supplements. We believe that a recommendation that consumers eat 5 to 10 servings of a wide variety of fruits and vegetables daily is an appropriate strategy for significantly reducing the risk of chronic diseases and to meet their nutrient requirements for optimum health.

Induction of apoptosis in human prostate cancer cell line, PC3, by 3,3'-diindolylmethane through the mitochondrial pathway

Prostate cancer is the most common malignancy and the second leading cause of male death in Western countries. Prostate cancer mortality results from metastases to the bones and lymph nodes and progression from androgen-dependent to androgen-independent disease. Although androgen ablation was found to be effective in treating androgen-dependent prostate cancer, no effective life-prolonging therapy is available for androgen-independent cancer. Epidemiological studies have shown a strong correlation between consumption of cruciferous vegetables and a lower risk of prostate cancer. These vegetables contain glucosinolates, which during metabolism give rise to several breakdown products, mainly indole-3-carbinol (I3C), which may be condensed to polymeric products, especially 3,3'-diindolylmethane (DIM). It was previously shown that these indole derivatives have significant inhibitory effects in several human cancer cell lines, which are exerted through induction of apoptosis. We have previously reported that I3C and DIM induce apoptosis in prostate cancer cell lines through p53-, bax-, bcl-2- and fasL-independent pathways. The objective of this study was examination of the apoptotic pathways that may be involved in the effect of DIM in the androgen-independent prostate cancer cell line, PC3, in vitro. Our results suggest that DIM induces apoptosis in PC3 cells, through the mitochondrial pathway, which involves the translocation of cytochrome c from the mitochondria to the cytosol and the activation of initiator caspase, 9, and effector caspases, 3 and 6, leading to poly ADP-ribose polymerase (PARP) cleavage and induction of apoptosis. Our findings may lead to the development of new therapeutic strategies for the treatment of androgen-independent prostate cancer.

Therapeutic activity of 3,3'-diindolylmethane on prostate cancer in an in vivo model

BACKGROUND

Prostate cancer (PC) is the second leading cancer-related death in men in Western countries. Hence, efficient anti-carcinogenic and therapeutic compounds against PC are badly needed. We have previously shown that 3,3'-diindolylmethane (DIM) has a suppressive effect on the growth of human breast and PC cell lines. The objective of this study was examination of the potential therapeutic effects of DIM in an in vivo model.

METHODS

TRAMP-C2, a mouse PC cell line, was injected into the flank of male C57BL/6 mice. When tumors appeared, mice were injected intraperitoneally with either corn oil (vehicle) or DIM (2.5, 5, or 10 mg per kg body weight) 3-times a week, for 3 weeks, and tumor volumes were measured bi-weekly with calibermeters. Later, the tumors were removed, their final weights and volumes were measured, and tumor sections were tested for histological studies.

RESULTS

DIM had a significant inhibitory effect, caused by diminished tumor growth. Histological examination of tumors from treated groups revealed apoptosis and decreased cell proliferation, compared with the controls. DIM didn't affect body weights or kidney and liver functioning.

CONCLUSIONS

The inhibitory action of DIM on tumor growth was demonstrated in vivo. Hence, this compound at the concentrations tested may offer an effective and non toxic therapeutic means against tumor growth in rodents, and may serve as a potential natural anti-carconigenic compound in humans.

RNA Adducts with Chlorophyll and Chlorophyllin: Stability and Structural Features

Porphyrins and their metal derivatives are strong nucleic acids binders. Some of these compounds have been used for radiation sensitization therapy of cancer and are targeted to interact with cellular DNA. Chlorophyll (Chl) binds DNA via guanine N-7 atom (major groove) and the backbone phosphate group (Neault and Tajmir-Riahi. Biophys. J. 76, 2177, 1999), whereas chlorophyllin (Chln) intercalates into A-T and G-C regions (Neault and Tajmir-Riahi. J. Phys. Chem. B. 102, 1610, 1998). This study was designed to examine the interaction of RNA with chlorophyll a and chlorophyllin in aqueous solution at physiological pH with pigment/RNA(phosphate) ratios (r) of 1/80 to 1/2. Fourier transform infrared (FTIR) and UV-visible difference spectroscopic methods were used to characterize the nature of pigment-RNA interaction and to establish correlation between spectral changes and the pigment binding mode, binding constant, RNA secondary structure and structural variations of pigment-RNA complexes in aqueous solution. Spectroscopic results showed that Chl and Chln bind RNA through G-C and A-U bases and the backbone phosphate group with overall binding constants of KChl = 1.95 x 10(5) M(-1) and KChln = 1.61 x 10(5) M(-1). The larger K value obtained for Chl-RNA complexes is attributed to the formation of more stable five or six-coordinate Mg cation in the RNA adducts, while the four-coordination Cu(II) in Chln can be more stable than that of the five or six-coordinated copper ion in the Chln-RNA complexes. Aggregation of pigment-RNA complexes occurs at high metalloporphyrin concentrations. No biopolymer secondary structural changes were observed upon pigment interaction and RNA remains in the A-family structure in these pigment complexes.

Commonly consumed and naturally occurring dietary substances affect biomarkers of oxidative stress and DNA damage in healthy rats

The influence of black currant juice, Bowman-Birk protease inhibitor (BBI), kolaviron (a biflavonoid fraction of Garcinia kola seed), sugars, vitamin C and tert-butyl hydroperoxide on a wide range of biomarkers for oxidative stress, DNA damage and sugar or lipid metabolism has been investigated in male F 344 rats. The selected pro-oxidant control, tert-butyl hydroperoxide, significantly increased plasma and liver 2-amino-adipic semialdehyde (AAS), a marker of protein oxidation (p <0.05) whereas lipid oxidation assessed as malon dialdehyde (MDA) and DNA oxidation were not significantly increased. Feeding BBI also increased the level of oxidized protein in plasma and liver at the higher dose level (0.5%). No effect was observed at the lower dose level (0.25%), which even decreased lipid oxidation in plasma. BBI did not affect background levels of DNA strand breaks or oxidation (comets). In rats exposed to black currant juice, a statistically significant decrease in liver AAS and MDA was observed. This effect could not be explained by its content of sugars or of the known redox active constituent, vitamin C. The lowering effect of black currant juice on protein and lipid oxidation was similar in magnitude to that of the known liver protectant, kolaviron. In rats treated with kolaviron (200 mg/kg body weight), background AAS levels were significantly reduced in both plasma and liver whereas the effect on MDA only reached statistical significance in plasma. Kolaviron was the only extract tested which decreased oxidative damage to DNA in the liver. The erythrocyte antioxidant enzyme activities, catalase and glutathione peroxidase were decreased in rats treated with tert-butyl hydroperoxide (p <0.05) but were not affected by the other treatments. Black currant juice and sugars increased plasma triglyceride levels and black currant juice increased plasma cholesterol but neither of them nor any other treatment affected blood glucose, erythrocyte HbA1c or fructosamine. We conclude that markers of oxidative stress may be modified by several mechanisms after feeding rats with complex dietary factors and that both pro- and antioxidant effects may consequently be observed simultaneously after short-term feeding of antioxidant-rich foods, herb medicines, or known pro- and antioxidants.

The challenge of measuring global fruit and vegetable intake

The WHO recently conducted, within its Global Burden of Disease 2000 Study, a Comparative Risk Assessment (CRA) to estimate the global health effect of low fruit and vegetable intake. This paper summarizes the methods used to obtain exposure data for the CRA and provides estimates of worldwide fruit and vegetable intakes. Intakes were derived from 26 national population-based surveys, complemented with food supply statistics. Estimates were stratified by 14 subregions, 8 age groups, and gender. Subregions were categorized on the bases of child mortality under age 5 y and 15- to 59-y-old male mortality (A: very low child and adult mortality; B: low child and adult mortality; C: low child, high adult mortality; D: high child and adult mortality; E: high child, very high adult mortality). Mean intakes were highest in Europe A [median = 449 g/(person.d)] and the Western Pacific Region A. They were lowest in America B [median = 192 g/(person.d)], and low in Europe C, the South East Asian Regions B and D, and Africa E. Children and elderly individuals generally had lower intakes than middle-aged adults. SDs varied considerably by region, gender, and age [overall median = 223 g/(person.d)]. Assessing exposure levels for the CRA had major methodological limitations, particularly due to the lack of nationally representative intake data. The results showed mean intakes generally lower than current recommendations, with large variations among subregions. If the burden of disease attributable to dietary factors is to be assessed more accurately, more countries will have to assess the dietary intake of their populations using comparable methods.

A novel natural inhibitor of extracellular signal-regulated kinases and human breast cancer cell growth

Water-soluble extracts of edible Vernonia amygdalina leaves were recently reported as potent inhibitors of cultured MCF-7 cells. The mechanism by which V. amygdalina inhibits MCF-7 cell growth has not been previously studied. The objective of this study was to evaluate the effects of V. amygdalina on the activities, DNA synthesis, and subsequent cell growth of extracellular signal-regulated protein kinases 1 and 2 (ERKs 1/2;). Treatment of cells with various concentrations (3-100 mg/ml) of water-soluble V. amygdalina extract potently inhibited ERK activities, DNA synthesis (P < 0.005), and cell growth (P < 0.01) in a concentration-dependent fashion, both in the absence and presence of serum. The growth rate of cells pretreated with 10 mg/ml V. amygdalina for 48 hrs before transfer to V. amygdalina-free medium was not significantly different (P > 0.05) from untreated cells. These results suggest that V. amygdalina, at least at concentrations up to 10 mg/ml, exhibits cytostatic action to retard the growth of human breast cancer cells. In addition, the ERK signaling pathways may be one or more of the intracellular targets for V. amygdalina antineoplastic actions.

Antioxidant and anticancer activity of extract from Betula platyphylla var. japonica

The antioxidant and anticancer properties of a medicinal plant, Betula platyphylla var. japonica were investigated. The total methanol extract of B. platyphylla var. japonica had protective effects against hydrogen peroxide (H2O2) in the Chinese hamster lung fibroblast (V79-4) cell line and induced apoptotic cell death in human promyelocytic leukemia (HL-60) cells, a cancer cell line. B. platyphylla var. japonica extract significantly increased cell viability against H2O2. The extract also showed high 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity (IC50 2.4 microg/ml) and lipid peroxidation inhibitory activity (IC50 below 4.0 microg/ml). Furthermore, B. platyphylla var. japonica extract reduced the number of V79-4 cells arrested in G2/M in response to H2O2 treatment and increased the activities of several cellular antioxidant enzymes, including superoxide dismutase, catalase and glutathione peroxidase. Treatment with B. platyphylla var. japonica extract induced cytotoxicity and apoptosis in HL-60 cells, as shown by nucleosomal DNA fragmentation, increases in the subdiploid cell population, and fluorescence microscopy. B. platyphylla var. japonica extract gradually increased the expression of pro-apoptotic Bax and led to the activation of caspase-3 and cleavage of PARP. These findings suggest that B. platyphylla var. japonica exhibits potential antioxidant and anticancer properties.

Dietary constituents as novel therapies for pain

The use of complementary and alternative medicine has dramatically increased in the United States. The effects of select dietary constituents in animal models and clinical pain states are reviewed. Specifically, the antinociceptive and analgesic properties of soybeans, sucrose, and tart cherries are discussed. The potential actions of dietary constituents as antiinflammatory and antioxidant agents are presented.