Tomatoes and risk of digestive-tract cancers

Can microplastics threaten plant productivity and fruit quality? Insights from Micro-Tom and Micro-PET/PVC

Solanum lycopersicum L., a crop grown worldwide with a high nutritional value for the human diet, was used to test the impact of microplastics on plant growth, productivity, and fruit quality. Two of the most represented microplastics in soils, polyethylene terephthalate (PET) and polyvinyl chloride (PVC), were tested. Plants were grown in pots with an environmentally realistic concentration of microplastics and, during the whole crop life cycle, photosynthetic parameters, number of flowers and fruits were monitored. At the end of the cultivation, plant biometry and ionome were evaluated, along with fruit production and quality. Both pollutants had negligible effects on shoot traits, with only PVC causing a significant reduction in shoot fresh weight. Despite an apparent low or no toxicity during the vegetative stage, both microplastics decreased the number of fruits and, in the case of PVC, also their fresh weights. The plastic polymer-induced decline in fruit production was coupled with wide variations in fruit ionome, with marked increases in Ni and Cd. By contrast there was a decline in the nutritionally valuable lycopene, total soluble solids, and total phenols. Altogether, our results reveal that microplastics can not only limit crop productivity but also negatively impact fruit quality and enhance the concentration of food safety hazards, thus raising concerns for their potential health risks for humans.

Associations between colorectal cancer risk and dietary intake of tomato, tomato products, and lycopene: evidence from a prospective study of 101,680 US adults

Background

Previous epidemiological studies have yielded inconsistent results regarding the effects of dietary tomato, tomato products, and lycopene on the incidence of colorectal cancer (CRC), possibly due to variations in sample sizes and study designs.

Methods

The current study used multivariable Cox regression, subgroup analyses, and restricted cubic spline functions to investigate correlations between CRC incidence and mortality and raw tomato, tomato salsa, tomato juice, tomato catsup, and lycopene intake, as well as effect modifiers and nonlinear dose-response relationships in 101,680 US adults from the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial.

Results

During follow-up 1100 CRC cases and 443 CRC-specific deaths occurred. After adjustment for confounding variables, high consumption of tomato salsa was significantly associated with a reduced risk of CRC incidence (hazard ratio comparing the highest category with the lowest category 0.8, 95% confidence interval 0.65-0.99, p for trend = 0.039), but not with a reduced risk of CRC mortality. Raw tomatoes, tomato juice, tomato catsup, and lycopene consumption were not significantly associated with CRC incidence or CRC mortality. No potential effect modifiers or nonlinear associations were detected, indicating the robustness of the results.

Conclusion

In the general US population a higher intake of tomato salsa is associated with a lower CRC incidence, suggesting that tomato salsa consumption has beneficial effects in terms of cancer prevention, but caution is warranted when interpreting these findings. Further prospective studies are needed to evaluate its potential effects in other populations.

Ranking based formula optimization, quality investigation, and real-time shelf-life prediction of ready-to-eat ricebean (Vigna umbellata) curry

Ricebean (Vigna umbellata) is an underutilized bean of South and South-East Asia, was exploited to formulate the ready-to-eat curry by using thermal processing technology. Eleven types of RTE ricebean curries (RBCs) namely RBC1, RBC2, RBC3, RBC4, RBC5, RBC6, RBC7, RBC8, RBC9, RBC10, RBC11 were developed by varying the proportion of tomato paste, onion paste, and coriander powder after thermal processing at 121 °C (15 psi) for 20 min. Out of these, the best quality curry was selected based on the total product ranking score (TPRS) which was calculated from the curry quality parameters such as consistency, pH, loss due to sorption onto the inner surface of the retort pouch (LOSS), and sensory (overall acceptability-OAA). Among the curries, RBC2 secured the highest value of TPRS, named it as RTE-RBC and was used to study the physico-chemical, textural, nutritional, microbial, sensory parameters and storage stability. The DPPH-antioxidant activity of RTE-RBC was 2.47 µM BHA/g which was due to the presence of bioactive phytochemicals such as polyphenol, flavonoids, lycopene, gingerol, ɣ-Oryzanol, and capsaicin. It was observed that the in-vitro protein/carbohydrate digestibility, in-vitro calcium bioavailability and real-time shelf-life (predicted) of RTE-RBC were 85%, 54%, and one year, respectively.

Radioprotective Potential of Nutraceuticals and their Underlying Mechanism of Action

Radiations are an efficient treatment modality in cancer therapy. Besides the treatment effects of radiations, the ionizing radiations interact with biological systems and generate reactive oxygen species that interfere with the normal cellular process. Previous investigations of synthetic radioprotectors have shown less effectiveness, mainly owing to some limiting effects. The nutraceuticals act as efficient radioprotectors to protect the tissues from the deleterious effects of radiation. The main radioprotection mechanism of nutraceuticals is the scavenging of free radicals while other strategies are involved modulation of signaling transduction of pathways like MAPK (JNK, ERK1/2, ERK5, and P38), NF-kB, cytokines, and their protein regulatory genes expression. The current review is focused on the radioprotective effects of nutraceuticals including vitamin E, -C, organosulphur compounds, phenylpropanoids, and polysaccharides. These natural entities protect against radiation-induced DNA damage. The review mainly entails the antioxidant perspective and mechanism of action of their radioprotective activities on a molecular level, DNA repair pathway, anti-inflammation, immunomodulatory effects, the effect on cellular signaling pathways, and regeneration of hematopoietic cells.

Nutritional Composition and Bioactive Compounds in Tomatoes and Their Impact on Human Health and Disease: A Review

Tomatoes are consumed worldwide as fresh vegetables because of their high contents of essential nutrients and antioxidant-rich phytochemicals. Tomatoes contain minerals, vitamins, proteins, essential amino acids (leucine, threonine, valine, histidine, lysine, arginine), monounsaturated fatty acids (linoleic and linolenic acids), carotenoids (lycopene and β-carotenoids) and phytosterols (β-sitosterol, campesterol and stigmasterol). Lycopene is the main dietary carotenoid in tomato and tomato-based food products and lycopene consumption by humans has been reported to protect against cancer, cardiovascular diseases, cognitive function and osteoporosis. Among the phenolic compounds present in tomato, quercetin, kaempferol, naringenin, caffeic acid and lutein are the most common. Many of these compounds have antioxidant activities and are effective in protecting the human body against various oxidative stress-related diseases. Dietary tomatoes increase the body's level of antioxidants, trapping reactive oxygen species and reducing oxidative damage to important biomolecules such as membrane lipids, enzymatic proteins and DNA, thereby ameliorating oxidative stress. We reviewed the nutritional and phytochemical compositions of tomatoes. In addition, the impacts of the constituents on human health, particularly in ameliorating some degenerative diseases, are also discussed.

Fish oil/lycopene microcapsules as a source of eicosapentaenoic and docosahexaenoic acids: a case study on spreads

BACKGROUND

The consumption of omega-3 fatty acids has many beneficial effects for human health, but the intake of foods rich in these fatty acids is not enough to achieve the recommended quantity per person and per day, and their direct addition in foods cause oxidation and unacceptable rancidity and off-flavor. Taking account of all these aspects, this study was aimed to develop stable microcapsules of fish oil (omega-3 polyunsaturated fatty acids) and lycopene (antioxidant) and to investigate their effect on different spreads.

RESULTS

The inclusion of different proportions of lycopene in fish oil did not show great benefits in the quality characteristics of emulsions and microcapsules. After the addition of fish oil and fish oil + lycopene microcapsules to dry-cured ham and cheese spreads, no significant differences were found in the proximal composition and oxidative stability, whereas fatty acids composition and sensory analysis were influenced. The eicosapentaenoic and docosahexaenoic acids content increased with the fish oil content in both products, but it decreased significantly after storage in the cheese spreads. Addition of microcapsules did not significantly influence on quantitative-descriptive and acceptability sensory analyses in dry-cured spreads, but it negatively affected the flavor of cheese spreading creams.

CONCLUSION

There is no need to add antioxidants to improve the stability of the fish oil microcapsules in the present study, which are appropriate as eicosapentaenoic acid and docosahexaenoic acid vehicles to enrich meat-derived spreading creams. © 2019 Society of Chemical Industry.

A high consumption of tomato and lycopene is associated with a lower risk of cancer mortality: results from a multi-ethnic cohort

Objective:

We investigated the association between the consumption of tomato and lycopene and cancer mortality among US adults.

Design:

Prospective.

Setting:

The National Health and Nutrition Examination Survey (1999–2010).

Participants:

Participants with estimated dietary data on tomato and lycopene consumption were included. Outcome data up until 31 December 2011 were also ascertained. Cox proportional hazard regression models were used to relate baseline tomato and lycopene consumption with cancer mortality. We conducted a competing-risk survival analysis to account for deaths from other causes.

Results:

Adjusted Cox models showed that tomato and lycopene intake were inversely related (hazard ratio (95 % CI)) to cancer mortality: 0·86 (0·81, 0·92) and 0·79 (0·74, 0·82), respectively. In the adjusted competing-risk models, the sub-hazard ratios (95 % CI) were 0·89 (0·83, 0·94) and 0·82 (0·78, 0·86) for cancer mortality for tomato and lycopene intake, respectively. No significant interaction was found for the association between tomato and lycopene consumption and cancer mortality while comparing older (aged >50 years) v. younger adults (Pinteraction > 0·173 for all) and obese v. non-obese (Pinteraction > 0·352 for all).

Conclusions:

Our results demonstrate the potential beneficial effects of a high dietary intake of tomato and lycopene on cancer death. Further prospective studies are needed to explore the association.

Dietary patterns and oral and pharyngeal cancer using latent class analysis

The methods traditionally used to identify a posteriori dietary patterns are principal components, factor and cluster analysis. The aim of our study is to assess the relationship between dietary patterns derived with latent class analysis (LCA) and oral/pharyngeal cancer risk (OPC), highlighting the strengths of this method compared to traditional ones. We analyzed data from an Italian multicentric case-control study on OPC including 946 cases and 2,492 hospital controls. Dietary patterns were derived using LCA on 25 food groups. A multiple logistic regression model was used to derive odds ratios (ORs) and corresponding 95% confidence intervals (CIs) for OPC according to the dietary patterns identified. We identified four dietary patterns. The first one was characterized by a high intake of leafy and fruiting vegetable and fruits (Prudent pattern), the second one showed a high intake of red meat and low intake of selected fruits and vegetables (Western pattern). The last two patterns showed a combination-type of diet. We labeled "Lower consumers-combination pattern" the cluster that showed a low intake of the majority of foods, and "Higher consumers-combination pattern" the one characterized by a high intake of various foods. Compared to the "Prudent pattern", the "Western" and the "Lower consumers-combination" ones were positively related to the risk of OPC (OR = 2.56, 95% CI: 1.90-3.45 and OR = 2.23, 95% CI: 1.64-3.02). No difference in risk emerged for the "Higher consumers-combination pattern" (OR = 1.28, 95% CI: 0.92-1.77).

Lycopene, sulforaphane, quercetin, and curcumin applied together show improved antiproliferative potential in colon cancer cells in vitro

Lycopene, sulforaphane, quercetin, and curcumin, ingredients of daily diet, show significant anticancer and chemopreventive potential; however, no data are available showing thorough evaluation of jointly used phytochemicals on cancer cell proliferation. Here, we compare anticancer potential of mentioned substances applied separately or in combination (as MIX) by measuring mitochondrial activity (MTT test), DNA synthesis (BrdU test) and lactate dehydrogenase release (LDH test) in colon epithelial (CCD841 CoTr), and colon cancer (HT-29, LS174T) cells. Additive inhibitory effect of simultaneously used phytochemicals on cancer cells proliferation has been shown. In epithelial cells, tested combination effectively inhibited mitochondrial activity, but not DNA synthesis. LDH test revealed cytotoxicity of tested mixture against cancer cells without negative effect on normal cells. Furthermore, we demonstrated that MIX enhances antiproliferative effect of common cytostatics: 5-fluorouracil and cisplatin. Presented data suggest chemopreventive potential of the proposed combination of natural substances and their usefulness as adjuvant strategy during chemotherapy. PRACTICAL APPLICATIONS: Colorectal cancer is one of the most common causes of cancer death worldwide. Since its development and progression is strongly correlated with dietary habits, healthy diet as well as supplementation with proved anticancer agents seems to be reasonable strategy of colon cancer prevention and treatment. In the present study, we have focused on four natural compounds abundantly found in daily diet i.e., lycopene, sulforaphane, quercetin, and curcumin, with well established anticancer potential. Their individual and collective impact both on normal colon epithelium cells and colon cancer cells viability, growth, and proliferation was examined. Furthermore, activity of the substances combined as MIX to influence antiproliferative potential of commonly used in colon cancer treatment cytostatics, 5-fluorouracil, and cisplatin was verified. Proposed in the study combination of phytochemicals with experimentally proven antiproliferative activity may propose an effective strategy for prevention and treatment of colon cancer.

Beneficial effects and potential risks of tomato consumption for human health: An overview

Tomato and its derived products have a very interesting nutritional value in addition to prominent antioxidant, anti-inflammatory, and anticancer activities. Tomatoes are generally quite safe to eat. However, overall consumption varies from individual to individual. Indeed, either beneficial or harmful effects of plants or their derived products are closely related to quality, including the presence of biologically active compounds. On the other hand, the synthesis and accumulation of these bioactive molecules depends on many other factors, such as environmental conditions. In this sense, this review briefly highlights the relationship between the chemistry of tomato and its derived products and their beneficial or harmful effects on human health, such as gastroesophageal reflux disease or heartburn, allergies, kidney and cardiovascular disorders, prostate cancer, irritable bowel syndrome, lycopenodermia, body aches, arthritis, and urinary problems.

Therapeutic potential of natural plant products and their metabolites in preventing radiation enteropathy resulting from abdominal or pelvic irradiation

Radiation-induced gastrointestinal injury or radiation enteropathy is an imminent risk during radiation therapy of abdominal or pelvic tumors. Despite remarkable technological advancements in image-guided radiation delivery techniques, the risk of intestinal injury after radiotherapy for abdominal or pelvic cancers has not been completely eliminated. The irradiated intestine undergoes varying degrees of adverse structural and functional changes, which can result in transient or long-term complications. The risk of development of enteropathy depends on dose, fractionation, and quality of radiation. Moreover, the patients' medical condition, age, inter-individual sensitivity to radiation and size of the treatment area are also risk factors of radiation enteropathy. Therefore, strategies are needed to prevent radiotherapy-induced undesirable alteration in the gastrointestinal tract. Many natural plant products, by virtue of their plethora of biological activities, alleviate the adverse effects of radiation-induced injury. The current review discusses potential roles and possible mechanisms of natural plant products in suppressing radiation enteropathy. Natural plant products have the potential to suppress intestinal radiation toxicity.

Lycopene: Is it Beneficial to Human Health as an Antioxidant?

It is well known that free oxygen radicals play an important role in the pathogenesis of several chronic disorders. Antioxidants are known as potential scavengers of reactive oxygen species that can protect biologic membranes against oxidative damage. Recent interest in phytochemicals has increased because of their protective effects against free oxygen radicals. Lycopene, which belongs to the carotenoid family, is the most effective singlet oxygen scavenger in vitro of all the carotenoids. Foods that contain lycopene and related supplements have been reported to prevent chronic diseases including cancer, asthma, and cardiovascular disorders. The aim of the article was to give a brief review of the antioxidant properties and beneficial health effects of lycopene.

Metabolomics-assisted biotechnological interventions for developing plant-based functional foods and nutraceuticals

Today, the dramatic changes in types of food consumed have led to an increased burden of chronic diseases. Therefore, the emphasis of food research is not only to ensure quality food that can supply adequate nutrients to prevent nutrition related diseases, but also to ensure overall physical and mental-health. This has led to the concept of functional foods and nutraceuticals (FFNs), which can be ideally produced and delivered through plants. Metabolomics can help in getting the most relevant functional information, and thus has been considered the greatest -OMICS technology to date. However, metabolomics has not been exploited to the best potential in plant sciences. The technology can be leveraged to identify the health promoting compounds and metabolites that can be used for the development of FFNs. This article reviews (i) plant-based FFNs-related metabolites and their health benefits; (ii) use of different analytic platforms for targeted and non-targeted metabolite profiling along with experimental considerations; (iii) exploitation of metabolomics to develop FFNs in plants using various biotechnological tools; and (iv) potential use of metabolomics in plant breeding. We have also provided some insights into integration of metabolomics with latest genome editing tools for metabolic pathway regulation in plants.

Carotenoids: biochemistry, pharmacology and treatment

Carotenoids and retinoids have several similar biological activities such as antioxidant properties, the inhibition of malignant tumour growth and the induction of apoptosis. Supplementation with carotenoids can affect cell growth and modulate gene expression and immune responses. Epidemiological studies have shown a correlation between a high carotenoid intake in the diet with a reduced risk of breast, cervical, ovarian, colorectal cancers, and cardiovascular and eye diseases. Cancer chemoprevention by dietary carotenoids involves several mechanisms, including effects on gap junctional intercellular communication, growth factor signalling, cell cycle progression, differentiation-related proteins, retinoid-like receptors, antioxidant response element, nuclear receptors, AP-1 transcriptional complex, the Wnt/β-catenin pathway and inflammatory cytokines. Moreover, carotenoids can stimulate the proliferation of B- and T-lymphocytes, the activity of macrophages and cytotoxic T-cells, effector T-cell function and the production of cytokines. Recently, the beneficial effects of carotenoid-rich vegetables and fruits in health and in decreasing the risk of certain diseases has been attributed to the major carotenoids, β-carotene, lycopene, lutein, zeaxanthin, crocin (/crocetin) and curcumin, due to their antioxidant effects. It is thought that carotenoids act in a time- and dose-dependent manner. In this review, we briefly describe the biological and immunological activities of the main carotenoids used for the treatment of various diseases and their possible mechanisms of action.

LINKED ARTICLES

This article is part of a themed section on Principles of Pharmacological Research of Nutraceuticals. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.11/issuetoc.

Lycopene and resveratrol pretreatment did not interfere with the liver of hepatectomized rats

Purpose:

To investigate the effects of lycopene and resveratrol pretreatment on hepatic hyperplasia in partially hepatectomized rats.

Methods:

The lycopene group and the resveratrol group received 40 mg/kg/day of lycopene or resveratrol, respectively (dissolved in olive oil or in saline solution, respectively) and administered via a gastric tube for 30 days. The partially hepatectomzed (PH) control groups received saline or olive oil via a gastric tube for 30 days, respectively, and the normal control group received no treatment. Liver tissue and intracardiac blood samples were obtained 24, 36 or 48 h after PH.

Results:

No areas of fibrosis were detected. No significant changes in mitotic index, in the number of apoptosis events or in aspartate aminotransferase and alanine aminotransferase levels were observed.

Conclusions:

Lycopene and resveratrol pretreatment did not interfere on hepatic hyperplasia in partially hepatectomized rats.

Safety assessment of a natural tomato oleoresin containing high amounts of Z-isomers of lycopene prepared with supercritical carbon dioxide

BACKGROUND

Z-isomers of lycopene, which are abundantly present in processed tomato products, are more bioavailable than (all-E)-lycopene found predominantly in raw tomatoes. Despite extensive studies on the bioavailability and biological activities of Z-isomers of lycopene, detailed studies on their safety and toxicology are limited.

RESULTS

The geno-, acute and subacute toxicities of tomato oleoresin that contained high amounts of lycopene Z-isomers (10.9% lycopene with 66.3% Z-isomer content) and had been prepared with supercritical carbon dioxide were investigated. The oleoresin was non-mutagenic in the Ames test with and without metabolic activation (S9 mix). The medial lethal dose (LD₅₀ ) of the oleoresin in rats, as determined by a single-dose oral test, was more than 5000 mg kg body weight^-1 (bw) [361 mg (Z)-lycopene kg bw^-1 ]. In the 4-week repeated-dose oral toxicity test, rats were administered oleoresin at 4500 mg kg^-1 day^-1 [325 mg (Z)-lycopene kg bw^-1 day^-1 ]. There were no clinically significant changes with respect to vital signs, physical examination outcomes and laboratory test values during the test period.

CONCLUSION

Based on our findings and as supported by its long history of consumption, tomato oleoresin that contains high amounts of Z-isomers of lycopene prepared with supercritical carbon dioxide can be considered as safe for human consumption. © 2016 Society of Chemical Industry.

Pharmacological Intervention through Dietary Nutraceuticals in Gastrointestinal Neoplasia

Neoplastic conditions associated with gastrointestinal (GI) tract are common worldwide with colorectal cancer alone accounting for the third leading rate of cancer incidence. Other GI malignancies such as esophageal carcinoma have shown an increasing trend in the last few years. The poor survival statistics of these fatal cancer diseases highlight the need for multiple alternative treatment options along with effective prophylactic strategies. Worldwide geographical variation in cancer incidence indicates a correlation between dietary habits and cancer risk. Epidemiological studies have suggested that populations with high intake of certain dietary agents in their regular meals have lower cancer rates. Thus, an impressive embodiment of evidence supports the concept that dietary factors are key modulators of cancer including those of GI origin. Preclinical studies on animal models of carcinogenesis have reflected the pharmacological significance of certain dietary agents called as nutraceuticals in the chemoprevention of GI neoplasia. These include stilbenes (from red grapes and red wine), isoflavones (from soy), carotenoids (from tomatoes), curcuminoids (from spice turmeric), catechins (from green tea), and various other small plant metabolites (from fruits, vegetables, and cereals). Pleiotropic action mechanisms have been reported for these diet-derived chemopreventive agents to retard, block, or reverse carcinogenesis. This review presents a prophylactic approach to primary prevention of GI cancers by highlighting the translational potential of plant-derived nutraceuticals from epidemiological, laboratory, and clinical studies, for the better management of these cancers through consumption of nutraceutical rich diets and their intervention in cancer therapeutics.

Exogenous antioxidants--Double-edged swords in cellular redox state: Health beneficial effects at physiologic doses versus deleterious effects at high doses

The balance between oxidation and antioxidation is believed to be critical in maintaining healthy biological systems. Under physiological conditions, the human antioxidative defense system including e.g., superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione (GSH) and others, allows the elimination of excess reactive oxygen species (ROS) including, among others superoxide anions (O₂^.-), hydroxyl radicals (OH.), alkoxyl radicals (RO.) and peroxyradicals (ROO.). However, our endogenous antioxidant defense systems are incomplete without exogenous originating reducing compounds such as vitamin C, vitamin E, carotenoids and polyphenols, playing an essential role in many antioxidant mechanisms in living organisms. Therefore, there is continuous demand for exogenous antioxidants in order to prevent oxidative stress, representing a disequilibrium redox state in favor of oxidation. However, high doses of isolated compounds may be toxic, owing to prooxidative effects at high concentrations or their potential to react with beneficial concentrations of ROS normally present at physiological conditions that are required for optimal cellular functioning. This review aims to examine the double-edged effects of dietary originating antioxidants with a focus on the most abundant compounds, especially polyphenols, vitamin C, vitamin E and carotenoids. Different approaches to enrich our body with exogenous antioxidants such as via synthetic antioxidants, diets rich in fruits and vegetables and taking supplements will be reviewed and experimental and epidemiological evidences discussed, highlighting that antioxidants at physiological doses are generally safe, exhibiting interesting health beneficial effects.

Adherence to the World Cancer Research Fund/American Institute for Cancer Research recommendations and head and neck cancers risk

OBJECTIVES

The World Cancer Research Fund (WCRF) and the American Institute for Cancer Research (AICR) have proposed eight recommendations for cancer prevention, related to body fatness, diet, and physical activity. Our aim is to evaluate the role of adherence to these recommendations on head and neck cancers risk.

MATERIALS AND METHODS

We obtained an overall score including seven of the WCRF/AICR recommendations, and examined its relationship with head and neck cancers risk in two Italian case-control studies including 946 patients with oral cavity and pharyngeal (OCP) cancer and 2492 controls, and 689 patients with laryngeal cancer and 1605 controls.

RESULTS

Higher adherence to WCRF/AICR recommendations was associated to a reduced risk of OCP cancer (odds ratio, OR=0.45, 95% confidence interval, CI: 0.33-0.62 for a score of 4-<5, and OR=0.32, 95% CI: 0.22-0.49 for a score of ⩾5 as compared to <3). The ORs for laryngeal cancer were 0.68 (95% CI: 0.50-0.92) for a score of 3-<4, 0.39 (95% CI: 0.28-0.55) for a score of 4-<5, and 0.24 (95% CI: 0.15-0.38) for a score of ⩾5.

CONCLUSION

Our study indicates that high adherence to the WCRF/AICR recommendations for cancer prevention is associated with a substantially decreased risk of head and neck cancers.

Can the Consumption of Tomatoes or Lycopene Reduce Cancer Risk?

Lycopene, a natural antioxidant found predominantly in to mato products, is attracting attention as a cancer prevention agent. Serum and dietary lycopene levels have been found to be inversely related to the incidence of several types of cancer, including prostate cancer. Although the antioxidant properties of lycopene are thought to be primarily responsible for its apparent beneficial effects, other mechanisms may also be involved. We outline the possible mechanisms of action of lycopene and review the current findings of in vitroand in vivostudies in cancer prevention and to some extent treatment. We examine the epidemiologic evidence regarding consumption of tomato and tomato products with the risk of cancer at various sites. Data suggest lycopene may account for or contribute to chemoprevention, but this hypothesis requires further study. Numerous other potentially beneficial compounds are present in tomatoes and complex interactions among multiple components may contribute to the anticancer properties of tomatoes.

Radioprotective Effects of Amifostine and Lycopene on Human Peripheral Blood Lymphocytes In Vitro

BACKGROUND

Radiation protection is a pivotal challenge for radiation workers employed in medical fields, industry, and also space professionals with an increasing role in medical diagnostic and therapeutic applications. Radioprotective effects of amifostine and lycopene and their ability to moderate the level of radiation-induced chromosomal aberrations were investigated using the dicentric chromosome assay.

METHODS

Parallel human whole blood samples, pretreated with amifostine (250 μg/mL), lycopene (5 μg/mL), and/or their combinations were irradiated for 30 minutes with ⁶⁰Co γ rays (1, 2, 3, and 4 Gy) with a dose rate of 98.46 cGy/min at SAD = 100 cm, in vitro and cocultured with control groups. The frequencies of chromosomal aberrations in the lymphocyte of the cells were analyzed.

RESULTS

There were no apparent chromosome aberrations in controls and also in the drug-treated groups in the absence of radiation. Radiodrug treatment significantly decreased frequency of the radiation-induced chromosome aberrations compared with radiation alone (P < .05). Amifostine reduced the frequency of radiation-induced dicentrics by 15.8%, 21.9%, 4.5%, and 11.6%, with dose protection factors (DPFs) of 1.2 ± 0.02, 1.3 ± 0.1, 1.05 ± 0.03, and 1.13 ± 0.02. Lycopene reduced the frequency by 17.2%, 3.07%, 1.63%, and 16.6%, with DPFs of 1.21 ± 0.12, 1.03±0.05, 1.02±0.03 and 1.12±0.03. The combination treatment reduced the frequency by 28%, 24.9%, 9%, and 31.2%, with DPFs of 1.38 ± 0.06, 1.33 ± 0.06, 1.09 ± 0.02, and 1.45 ± 0.03 with radiation doses of 1, 2, 3, and 4 Gy, respectively.

CONCLUSIONS

It can be suggested that pretreatment with combined amifostine and lycopene may reduce the extent of ionizing radiation damage in cells.

Phytochemicals as Innovative Therapeutic Tools against Cancer Stem Cells

The theory that several carcinogenetic processes are initiated and sustained by cancer stem cells (CSCs) has been validated, and specific methods to identify the CSCs in the entire population of cancer cells have also proven to be effective. This review aims to provide an overview of recently acquired scientific knowledge regarding phytochemicals and herbal extracts, which have been shown to be able to target and kill CSCs. Many genes and proteins that sustain the CSCs’ self-renewal capacity and drug resistance have been described and applications of phytochemicals able to interfere with these signaling systems have been shown to be operatively efficient both in vitro and in vivo. Identification of specific surface antigens, mammosphere formation assays, serial colony-forming unit assays, xenograft transplantation and label-retention assays coupled with Aldehyde dehydrogenase 1 (ALDH1) activity evaluation are the most frequently used techniques for measuring phytochemical efficiency in killing CSCs. Moreover, it has been demonstrated that EGCG, curcumin, piperine, sulforaphane, β-carotene, genistein and the whole extract of some plants are able to kill CSCs. Most of these phytochemicals act by interfering with the canonical Wnt (β-catenin/T cell factor-lymphoid enhancer factor (TCF-LEF)) pathway implicated in the pathogenesis of several cancers. Therefore, the use of phytochemicals may be a true therapeutic strategy for eradicating cancer through the elimination of CSCs.

The role of antioxidants in the chemistry of oxidative stress: A review

This Review Article is focused on the action of the reactive oxygenated species in inducing oxidative injury of the lipid membrane components, as well as on the ability of antioxidants (of different structures and sources, and following different mechanisms of action) in fighting against oxidative stress. Oxidative stress is defined as an excessive production of reactive oxygenated species that cannot be counteracted by the action of antioxidants, but also as a perturbation of cell redox balance. Reactive oxygenated/nitrogenated species are represented by superoxide anion radical, hydroxyl, alkoxyl and lipid peroxyl radicals, nitric oxide and peroxynitrite. Oxidative stress determines structure modifications and function modulation in nucleic acids, lipids and proteins. Oxidative degradation of lipids yields malondialdehyde and 4-hydroxynonenal, but also isoprostanes, from unsaturated fatty acids. Protein damage may occur with thiol oxidation, carbonylation, side-chain oxidation, fragmentation, unfolding and misfolding, resulting activity loss. 8-hydroxydeoxyguanosine is an index of DNA damage. The involvement of the reactive oxygenated/nitrogenated species in disease occurrence is described. The unbalance between the oxidant species and the antioxidant defense system may trigger specific factors responsible for oxidative damage in the cell: over-expression of oncogene genes, generation of mutagen compounds, promotion of atherogenic activity, senile plaque occurrence or inflammation. This leads to cancer, neurodegeneration, cardiovascular diseases, diabetes, kidney diseases. The concept of antioxidant is defined, along with a discussion of the existent classification criteria: enzymatic and non-enzymatic, preventative or repair-systems, endogenous and exogenous, primary and secondary, hydrosoluble and liposoluble, natural or synthetic. Primary antioxidants are mainly chain breakers, able to scavenge radical species by hydrogen donation. Secondary antioxidants are singlet oxygen quenchers, peroxide decomposers, metal chelators, oxidative enzyme inhibitors or UV radiation absorbers. The specific mechanism of action of the most important representatives of each antioxidant class (endogenous and exogenous) in preventing or inhibiting particular factors leading to oxidative injury in the cell, is then reviewed. Mutual influences, including synergistic effects are presented and discussed. Prooxidative influences likely to occur, as for instance in the presence of transition metal ions, are also reminded.

Evaluation of heavy metals, cytotoxicity, and antioxidant activity of tomatoes grown in toxic muddy soils

This research studies tomatoes grown in polluted soils to ascertain their phytochemical and nutritive features. Pulp and seeds from tomatoes grown in muddy soils were analyzed for their antioxidant power and their toxicity because of the possibility that heavy metals were present in the soils. An antioxidant assay on methanol extracts was made by using DDPH, while an ABTS [2,2'-Azino-bis-(3-ethylbenzthiazoline-6-sulfonic acid)] assay was used to evaluate the antioxidant activity of lipophilic fractions. Results of the antioxidant assay showed that the tomatoes maintained a high level of antioxidant activity especially in the lipophilic fractions which contain the most representative compounds. Cytotoxic activity was performed on HeLa, PDAC, and A375 cell lines by [3-(4,5-dimethylthiazol-2-yl)-2,5-phenyl-2H-tetrazolium bromide] (MTT) assay. Results showed that neither the seeds, nor the pulp, of the extracts was cytotoxic. The presence of heavy metals was evaluated by using spectroscopy of atomic absorption with a graphite oven. Test results show the absence of heavy metals and these results have an interesting scientific role because they provide useful information for promoting food safety.

Lycopene as a carotenoid provides radioprotectant and antioxidant effects by quenching radiation-induced free radical singlet oxygen: an overview

Radio-protectors are agents that protect human cells and tissues from undesirable effects of ionizing radiation by mainly scavenging radiation-induced free radicals. Although chemical radio-protectors diminish these deleterious side effects they induce a number of unwanted effects on humans such as blood pressure modifications, vomiting, nausea, and both local and generalized cutaneous reactions. These disadvantages have led to emphasis on the use of some botanical radio-protectants as alternatives. This review has collected and organized studies on a plant-derived radio-protector, lycopene. Lycopene protects normal tissues and cells by scavenging free radicals. Therefore, treatment of cells with lycopene prior to exposure to an oxidative stress, oxidative molecules or ionizing radiation may be an effective approach in diminishing undesirable effects of radiation byproducts. Studies have designated lycopene to be an effective radio-protector with negligible side effects.

Effect of photo-selective nettings on post-harvest quality and bioactive compounds in selected tomato cultivars

BACKGROUND

Photo-selective coloured netting is referred to as a 'new agro-technological' concept adopted to manipulate light quality changes that can induce favourable responses in plants.

RESULTS

Tomato (Solanum lycopersicum L.) cultivars AlvaV, Irit and SCX 248 grown under the black net (commercial net, 25% shading) showed higher weight loss, loss of firmness, ascorbic acid content and decline in the ratio of soluble solids content/titrable acidity during post-harvest storage (low-temperature storage at 10°C and 90% relative humidity for 21 days followed by market shelf conditions at 25°C for 2 days). During post-harvest storage, lycopene, β-carotene, total phenolic content and antioxidant scavenging activity were higher in cvs AlfaV and Irit grown under the black or pearl nets. However, the β-carotene, total phenolic content and antioxidant scavenging activity were higher in SCX 248 grown under the red net during post-harvest storage. Cultivar AlfaV grown under the red and pearl nets had a higher number of odour active aroma compounds during post-harvest storage. Panellists preferred cv. AlfaV grown under the pearl nets after storage based on taste, overall appearance and firm textured fruits.

CONCLUSION

Pearl photo-selective nets retained the overall fruit quality and bioactive components in cvs AlfaV and Irit during post-harvest storage. Red photo-selective nets, however, showed greater influence on retention of overall fruit quality and bioactive compounds in cv. SCX 248 during post-harvest storage.

Non-alcoholic steatohepatitis and hepatocellular carcinoma: implications for lycopene intervention

Increased prevalence of non-alcoholic fatty liver disease (NAFLD) is one of the consequences of the current obesity epidemic. NAFLD is a major form of chronic liver disease that is highly prevalent in obese and overweight adults and children. Nonalcoholic steatohepatitis (NASH) is the severe form of NAFLD, and uncontrolled inflammation as displayed in NASH has been identified as one of the key events in enhancing hepatic carcinogenesis. Lycopene is a non-provitamin A carotenoid and the pigment principally responsible for the characteristic deep-red color of ripe tomato and tomato products, as well as some fruits and vegetables. Lycopene's innate antioxidant and anti-inflammatory properties have generated research interests on its capacity to protect against human diseases that are associated with oxidative stress and inflammation. In addition, differential mechanisms of lycopene metabolism including endogenous cleavage by carotenoid cleavage oxygenases (BCOs), generate lycopene metabolites that may also have significant impact on human disease development. However, it remains to be elucidated as to whether lycopene or its metabolites apolycopenoids have protective effects against obesity-related complications including inflammation and tumorigenesis. This article summarizes the in vivo experiments that elucidated molecular mechanisms associated with obesity-related hepatic inflammation and carcinogenesis. This review also provides an overview of lycopene metabolism, and the molecular pathways involved in the potential beneficial properties of lycopene and apolycopenoids. More research is clearly needed to fully unravel the importance of BCOs in tomato carotenoid metabolism and the consequence on human health and diseases.

Effect of water-soluble fraction of cherry tomatoes on the adhesion of probiotics and Salmonella to intestinal epithelial cells

BACKGROUND

Tomato is one of the most consumed vegetables in the world and contains many valuable nutritional components. Here we investigate the prebiotic effects of cherry tomatoes for improving gut health.

RESULTS

Water-soluble dietary fiber was prepared from fresh and processed (heat treatment at 80 °C for 15 min) cherry tomato samples, each with and without Viscozyme L treatment. In the adhesion assays, all water-soluble dietary fiber samples improved adhesion of probiotics (Lactobacillus rhamnosus and Bifidobacterium bifidum) to intestinal epithelial cells (Caco-2 cells). Heat treatment in the preparation of juice from cherry tomatoes showed no significant effect on the adhesion of probiotics to Caco-2 cells. The oligofructose content of samples affected the intestinal adhesion of probiotic bacteria, with higher oligosaccharide concentrations associated with greater adhesion of probiotics and more inhibition of the adhesion of pathogens to Caco-2 cells.

CONCLUSION

The present results suggest that cherry tomato can act as a prebiotic, with oligofructose potentially being one of its major prebiotic components.

Lycopene modulates initiation of N-nitrosodiethylamine induced hepatocarcinogenesis: studies on chromosomal abnormalities, membrane fluidity and antioxidant defense system

Oxidative damage due to free radicals generated during nitrosamine metabolism has been suggested as one of the major cause for the initiation of hepatocarcinogenesis. Lycopene, is a well known antioxidant and have promising preventive potentials, however the mechanism of action remain hypothetical and unclear. To investigate the involvement of lycopene extracted from tomatoes (LycT) against oxidative stress induced deleterious effect of N-nitrosodiethylamine (NDEA) on cellular macromolecules, female Balb/c mice were divided in four groups: Control, NDEA (cumulative dose of 200mg NDEA/kg body weight injected intraperitoneally in 8 weeks), LycT (5mg/kg body weight given orally on alternate days, throughout the study) and LycT+NDEA (co-administration of LycT and NDEA). NDEA treatment commenced after 2 weeks of LycT administration. At the end of NDEA exposure i.e., at 10th week, enhanced activities of hepatic phase I enzymes, levels of reactive oxygen species (ROS), lipid peroxidation (LPO) was observed in NDEA group which may have contributed in chromosomal aberrations, enhanced micronucleated cell score, membrane fluidity and serum liver marker enzymes. A significant decrease in enzymatic and non-enzymatic antioxidant system could delineate the mechanism behind such NDEA insults. LycT pre-treatment to NDEA challenged group showed lower chromosomal abnormalities, micronucleated cells score, ROS, LPO levels and liver enzymes. Lycopene aids in normalizing the membrane fluidity and enhancing the activity of antioxidant enzymes and reduced glutathione which could account for the reduced oxidative damage in LycT+NDEA group. It seemed that lycopene supplementation target multiple dys-regulated pathways during initiation of carcinogenesis. Thus, dietary supplementation with lycopene can serve as an alternate measure to intervene the initiation of carcinogenesis.

Bioactivity of tomato hybrid powder: antioxidant compounds and their biological activities

The antioxidant and cytotoxic activities and the polyphenolic and anthocyanin contents of tomato hybrid powders were studied. Tomato powders were obtained, starting from the fresh fruits that had undergone an industrial process of drying and pulverization at two different temperatures. Antioxidant activities were evaluated in different extracts by using spectrophotometric assays: 2,2'-azino-bis-(3-ethylbenzthiazoline-6-sulfonic acid and N,N-dimethyl-p-phenylenediamine dihydrochloride cation radical inhibition for lipophilic and hydrophilic extracts, respectively, and 2,2-diphenyl-1-picrylhydrazyl radical scavenging assay for polyphenolic extracts. Moreover, polyphenolic and anthocyanin contents were also carried out to detect the presence of these bioactive compounds. The effect of cytotoxic activity in vitro of tomato hybrid powder extracts on T47D (human breast carcinoma) cells was also evaluated. Results showed good antioxidant activities in lipophilic, polyphenolic, and hydrophilic extracts of samples that were obtained at a lower temperature. Extracts of the sample obtained at a higher temperature presented moderate antioxidant activity, lower than the extracts of other samples, which was probably due to the loss of labile antioxidant compounds during the industrial process. Very interesting was the presence of anthocyanins in both samples, even if in traces, and also a moderate cytotoxicity of a lipophilic extract on T47D cells. Therefore, tomato hybrid powders, on the basis of their multifunctional properties, could have a biotechnological application in agri-food or cosmetic industries as an additive for improving nutritional and/or bioactive qualities of commercial products used in daily nutrition and cosmetics.

The role of tomato products and lycopene in the prevention of gastric cancer: a meta-analysis of epidemiologic studies

BACKGROUND

Gastric cancer is the second most common cause of death from cancer worldwide. Epidemiologic studies have examined the possible association between tomato products consumption and gastric cancer, but the relationship between tomato products and the risk of gastric cancer is controversial. We performed a meta-analysis of cohort and case-control studies to analyze this association.

METHODS

We systematically searched MEDLINE and EMBASE and contacted authors to identify potential studies published from January 1966 to June 2012. We pooled the relative risks from individual studies using a random-effects model and performed heterogeneity and publication bias analyses.

RESULTS

Twenty-one studies were eligible for our inclusion criteria, in a pooled analysis of all studies, consumption of large amounts of tomato products (in a comparison of the highest and lowest consumption groups) reduced the risk for gastric cancer (odds ratio, 0.73; 95% confidence interval, 0.60-0.90). The pooled OR of lycopene consumption and serum lycopene was 0.88 (95% CI=0.67-1.16) and 0.79 (95% CI=0.59-1.07), respectively.

CONCLUSIONS

Consumption of large amounts of tomato products is associated with a reduced risk of gastric cancer. However, because of potential confounding factors and exposure misclassification, further studies are required to establish these findings.

Lycopene induces retinoic acid receptor transcriptional activation in mice

SCOPE

Lycopene is a lipophilic carotenoid and provides the red colour to tomatoes and tomato product. Various studies indicated that lycopene and tomatoes/tomato products are able to positively influence various diseases associated with a chronic inflammation. The mechanism of action of lycopene to elicit these effects is partly unknown. A possible mechanism is that biological metabolites of lycopene may activate nuclear hormone receptors in mammalian cells. The aim of this study was to investigate the potential of orally administered lycopene and all-trans retinoic acid (ATRA) for the induction of the retinoic acid receptor (RAR) in a transgenic retinoic acid response-element (RARE)-reporter mouse system.

METHODS AND RESULTS

Orally administered lycopene (100 mg/kg bw in beadlets, n = 6) and ATRA as an endogenous RAR ligand (50 mg/kg bw, n = 6) for the induction of the retinoic acid receptor in male mice using a transgenic RARE-reporter mouse system.

CONCLUSION

Lycopene treatments induced RARE-mediated cell signalling indicated by quantified bioimaging, increased luciferase activity and up-regulated the retinoid target genes in selected organs of the mice. We conclude that lycopene can induce RAR-transcriptional activation in mice and lycopene might be a precursor of still non-identified biologically active metabolites.

Concomitant consumption of lycopene and fish oil inhibits tumor growth and progression in a mouse xenograft model of colon cancer

SCOPE

Our previous report showed that concomitant supplementation of lycopene and eicosa-pentaenoic acid synergistically inhibited the proliferation of human colon cancer HT-29 cells in vitro.

METHODS AND RESULTS

To validate our findings, the present study investigated whether consumption of lycopene and fish oil would help prevent tumor growth and progression in a mouse xenograft model of colon cancer. The inhibitory effects of lycopene and fish oil on tumor growth were verified by western blotting analysis, bioluminescent imaging, immunohistochemical (IHC) staining and ELISA. The results demonstrated that lycopene and fish oil synergistically inhibited the growth of colon cancer in tumor-bearing mice. The bioluminescent imaging, histopathological and IHC staining results indicated that lycopene and fish oil effectively suppressed tumor growth and progression of colon cancer in vivo. The chemopreventive effects of lycopene and fish oil were associated with augmented expression of the cell cycle inhibitors such as p21(CIP1/WAF1) and p27(Kip1) , and suppression of proliferating cell nuclear antigen, β-catenin, cyclin D1 and c-Myc proteins. Furthermore, lycopene and fish oil inhibited tumor progression through suppression of MMP-7, MMP-9, COX-2 and PGE2.

CONCLUSION

These results show that lycopene and fish oil act synergistically as chemopreventive agents against tumor growth and progression in a mouse xenograft model of colon cancer.

Effect of lycopene on cell viability and cell cycle progression in human cancer cell lines

BACKGROUND

Lycopene, a major carotenoid component of tomato, has a potential anticancer activity in many types of cancer. Epidemiological and clinical trials rarely provide evidence for mechanisms of the compound's action, and studies on its effect on cancer of different cell origins are now being done. The aim of the present study was to determine the effect of lycopene on cell cycle and cell viability in eight human cancer cell lines.

METHODS

Human cell lines were treated with lycopene (1-5 μM) for 48 and 96 h. Cell viability was monitored using the method of MTT. The cell cycle was analyzed by flow cytometry, and apoptotic cells were identified by terminal deoxynucleotidyl transferase-mediated dUTP nick labeling (TUNEL) and by DAPI.

RESULTS

Our data showed a significant decrease in the number of viable cells in three cancer cells lines (HT-29, T84 and MCF-7) after 48 h treatment with lycopene, and changes in the fraction of cells retained in different cell cycle phases. Lycopene promoted also cell cycle arrest followed by decreased cell viability in majority of cell lines after 96 h, as compared to controls. Furthermore, an increase in apoptosis was observed in four cell lines (T-84, HT-29, MCF-7 and DU145) when cells were treated with lycopene.

CONCLUSIONS

Our findings show the capacity of lycopene to inhibit cell proliferation, arrest cell cycle in different phases and increase apoptosis, mainly in breast, colon and prostate lines after 96 h. These observations suggest that lycopene may alter cell cycle regulatory proteins depending on the type of cancer and the dose of lycopene administration. Taken together, these data indicated that the antiproliferative effect of lycopene was cellular type, time and dose-dependent.

Spectroscopic characterization of lycopene extract from Lycopersicum esculentum (Tomato) and its evaluation as a chemopreventive agent against experimental hepatocarcinogenesis in mice

The present study was designed to characterize the lycopene extract (LycT) prepared from tomatoes (Lycopersicum esculentum) and then to evaluate its chemopreventive efficacy in N-diethylnitrosamine (NDEA)-induced experimental hepatocarcinogenesis in female Balb/c mice. The extraction of lycopene was carried out using hexane/acetone/ethanol as an extracting medium and then characterized by ultraviolet-visible, nuclear magnetic resonance and Fourier transform infrared spectroscopy. Chemopreventive efficacy of characterized LycT in vivo was evaluated in terms of hepatic tumour incidence, multiplicity, burden, hepatosomatic index and animal survival rate. Results indicated that average lycopene content of the tomato was 11.6-14 mg/kg tomato weight. Spectroscopic data confirmed the structural characteristics of lycopene in the extract. In the animal study, reduction in tumour incidence (42.05%), tumour burden (1.39) and tumour multiplicity (3.42) was observed upon LycT pretreatment to NDEA-treated animals. Histopathological analysis unravelled that the increased survival rate in LycT + NDEA-treated animals was due to the delay in the formation of aggressive tumour nodules. These observations indicate that lycopene seems to be an able candidate for chemoprevention in hepatocarcinogenesis resulting from NDEA insults.

Cancer chemopreventive effects of lycopene: suppression of MMP-7 expression and cell invasion in human colon cancer cells

Clinical studies indicate that high blood levels of leptin or matrix metalloproteinase-7 (MMP-7; matrilysin) proteins are associated with tumor progression of human colorectal cancer (CRC). Leptin could play an important role in cell migration and invasion of cancer cells. Our previous study indicated that lycopene could inhibit the proliferation of human colon cancer cells in vitro. However, the inhibitory effects of lycopene on the progression of human colon cancer cells have not been demonstrated yet. In this study, we investigated the inhibitory effects of lycopene on tumor progression including cell invasion and MMP-7 expression in leptin-stimulated human colon cancer cells in vitro. Our results demonstrated that lycopene significantly inhibited leptin-mediated cell invasion and MMP-7 expression in human colon cancer HT-29 cells. Lycopene could augment the expression and stability of E-cadherin proteins. Our results showed that MAPK/ERK and PI3K/Akt signaling pathways played important roles in leptin-mediated MMP-7 expression and cell invasion. Lycopene could effectively inhibit the phosphorylation of Akt, glycogen synthase kinase-3β (GSK-3β) and ERK 1/2 proteins. The molecular mechanisms of lycopene were in part through decreases in nuclear levels of AP-1 and β-catenin proteins. These novel findings suggested that lycopene could act as a chemopreventive agent to suppress MMP-7 expression and leptin-mediated cell invasion in human colon cancer HT-29 cells.