Lycopene: chemistry, biology, and implications for human health and disease

Rat intestinal homogenate and pancreatic juice can induce the Z-isomerization of all-E-lycopene in vitro

Lycopene is one of the carotenoids often consumed by humans in their diet. Although lycopene exists mainly in the form of the all E-isomer in foods, the considerable quantity of its Z-isomers is found in the human plasma and liver. This observation suggested that the lycopene all-E-isomer was converted into Z-isomers in the human body. In this study, the Z-isomerization of the all-E-isomer was induced in vitro by the pancreatic juice and small intestinal homogenate of male rats under the conditions of 37 °C, pH = 7.5, nitrogen and darkness, as well as shaking. After 2 hours, the proportion of the all E-isomer decreased to 25% and Z-isomer amounts increased relatively. The converted products were identified as 5, 9, and 11 Z-isomers by electronic absorption spectroscopy and mass spectrometry (MS). The observations from this experiment suggested that the Z-isomerization site of the lycopene all E-isomer was located in the small intestinal wall of the rat.

Lycopene alleviates oxidative stress via the PI3K/Akt/Nrf2pathway in a cell model of Alzheimer's disease

Background & Aims

Oxidative stress (OS) plays an important role in neurodegenerative diseases such as Alzheimer’s disease (AD). Lycopene is a pigment with potent antioxidant and anti-tumor effects. However, its potential role in central nervous system is not well-defined. The aim of this study was to investigate the effect of lycopene on the cell model of AD and determine its underlying mechanisms.

Methods

M146L cell is a double-transfected (human APP gene and presenlin-1 gene) Chinese hamster ovary (CHO) cell line that overexpresses β -amyloid (Aβ) and is an ideal cell model for AD. We treated cells with lycopene, and observed the effect of lycopene on M146L cells.

Results

Oxidative stress and apoptosis in M146L cells were significantly higher than those in CHO cells, suggesting that Aβ induced OS and apoptosis. Lycopene alleviated OS and apoptosis, activated the PI3K/Akt/Nrf2 signaling pathway, upregulated antioxidant and antiapoptotic proteins and downregulated proapoptotic proteins. Additionally, lycopene inhibited β -secretase (BACE) activity in M146L cells. These results suggest that lycopene inhibits BACE activity and protects M146L cells from oxidative stress and apoptosis by activating the PI3K/Akt/Nrf2 pathway.

Conclusion

Lycopene possibly prevents Aβ-induced damage by activating the PI3K/Akt/Nrf2 signaling pathway and reducing the expression of BACE in M146L cells.

Protection of Lycopene against Embryonic Anomalies and Yolk Sac Placental Vasculogenic Disorders Induced by Nicotine Exposure

Identification of a new agent from natural products for the protection of embryonic anomalies is potentially valuable. To investigate the protective effect exerted by lycopene against nicotine-induced malformations, mouse embryos in embryonic day 8.5 with yolk sac placentas were cocultured with 1 mM nicotine and/or lycopene (1 × 10^-6, 1 × 10^-5 μM) for 48 h. The morphological defects and apoptotic cell deaths in the embryo and yolk sac placenta of the nicotine group were significantly increased. Exposure to nicotine resulted in reduced superoxide dismutase (SOD) activity and cytoplasmic SOD and cytoplasmic glutathione peroxidase mRNA levels, but increased lipid peroxidation level in embryos. Moreover, treatment with nicotine resulted in aggravated expressions of the mRNA or protein level of antiapoptotic (BCL2-associated X protein, B-cell lymphoma-extralarge, and caspase 3), anti-inflammatory (nuclear factor kappa-light-chain-enhancer of activated B cells and tumor necrosis factor-alpha), and vasculogenic (vascular endothelial growth factor-alpha, insulin-like growth factor-1, alpha smooth muscle actin, transforming growth factor-beta 1, and hypoxia inducible factor-1 alpha) factors in the embryo and yolk sac placenta. However, all the parameters were significantly improved by treatment with lycopene, as compared to the nicotine group. These findings indicate the potential of lycopene as a protective agent against embryonic anomalies and yolk sac vasculogenic and placenta-forming defects induced by nicotine through modulations of oxidative, apoptotic, vasculogenic, and inflammatory activities.

Lycopene supplementation regulates the gene expression profile and fat metabolism of breeding hens

This study investigated the effects of lycopene on the gene expression profile and expression of genes related to fat metabolism of Xinghua breeding hens. Seven hundred and twenty healthy breeding hens were randomly assigned to four treatments; each treatment was replicated six times with 30 hens each. Broken rice and soybean meal were adopted for the basal diet and added with 0 (control group), 20, 40 and 80 mg/kg lycopene respectively. Gene expression profile of the liver induced by lycopene and expression of genes related to fat metabolism in hens liver and intestine were analysed after 42-day feeding trial including 7-day pre-feeding period and 35-day formal period. The genes involved in fat metabolism were analysed, and we found that lycopene significantly increased the expression of PGC1α, PPARα, RXRα and RARα in the liver, PPARγ, RXRα and RXRγ in the jejunum, and RARα in the duodenum (p < .05); reduced the expression of FABP1 and FABP10 in the liver, and FATP4 in the jejunum (p < .05). By analysing gene expression profile, 158 differentially expressed genes (DEGs) including 69 up-regulated genes and 89 down-regulated genes were obtained between control group and 40 mg/kg group. KEGG pathway analysis was performed on all DEGs, and 5 pathways were obtained. In conclusion, lycopene can affect the expression of related genes, and this may be one of the reasons that lycopene can regulate fat metabolism.

Lower serum levels of alpha tocopherol and lycopene are associated with higher pain and physical disability in subjects with primary knee osteoarthritis: A case-control study

Background: We aimed to determine dietary intake and serum concentration of α-tocopherol and lycopene in subjects with knee osteoarthritis (KOA) in relation to pain intensity and functional status and comparing them with healthy controls. Methods: This case-control study was conducted among 35 patients with primary KOA and 35 matched healthy subjects selected using convenience sampling method. Dietary intakes of alpha-tocopherol and lycopene were estimated from 24-hour dietary records. Visual Analogue Scale (VAS) and Western Ontario and McMaster (WOMAC) index were used to assess the pain and functional status, respectively. Results: Serum concentrations of alpha-tocopherol (0.024 ± 0.005 vs. 0.028 ± 0.007 μmol/ml, p-value =  0.021) and lycopene (0.616 ± 0.191 vs. 0.727 ± 0.159 μmol/l, p-value = 0.011) were significantly lower in OA patients in comparison with healthy controls. Dietary intake of alpha-tocopherol was negatively associated with total WOMAC score (r = -0.401, p-value = 0.021) and pain (r = -0.356, p-value = 0.042) and physical function (r = -0.355, p-value = 0.043) subscales. Dietary intake of lycopene was negatively associated with total WOMAC score (r = -0.616, p-value < 0.001) and pain (r = -0.348, p-value = 0.047) and physical function (r = -0.606, p-value < 0.001) subscales. Additionally, serum concentration of alpha-tocopherol was negatively associated with total WOMAC score (r = -0.574, p-value < 0.001) and physical function subscale (r = -0.571, p-value < 0.001). Serum concentration of lycopene was negatively associated with total WOMAC score (r = -0.360, p-value = 0.040) and physical function subscale (r = -0.350, p-value = 0.046) Conclusion: Serum concentrations of α-tocopherol and lycopene were significantly lower in patients with KOA than in healthy controls. Significant negative association was detected between serum concentration and dietary intake of α-tocopherol and lycopene with functional disability in patients with KOA.

Lycopene attenuates chronic prostatitis/chronic pelvic pain syndrome by inhibiting oxidative stress and inflammation via the interaction of NF-κB, MAPKs, and Nrf2 signaling pathways in rats

Background

Chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) is identified as a urinary andrological diseases that afflict men due to various discomforts. It is urgent and meaningful to develop the novel and effective treatments as a result of the unclear etiology and dismal therapeutic effect of CP/CPPS. Lycopene exerts a crucial role in numerous chronic inflammatory diseases owing to its potent antioxidant capacity.

Objective

This study aimed to observe the effect of lycopene on CP/CPPS and to explore the underlying mechanisms.

Materials and Methods

A CP/CPPS model with complete Freund's adjuvant was established in this study. Afterward, intragastric lycopene or corn oil was administered daily for 4 consecutive weeks. Finally, the cardiac blood and prostate tissue samples were collected from rats to carry out related evaluation and testing.

Results

It was found in this study that lycopene alleviated changes in prostate histopathology compared with those in the complete Freund's adjuvant‐induced CP/CPPS model rats without lycopene treatment. Furthermore, lycopene was suggested to reduce the levels of chemokines MCP1 and MIP‐1α, down‐regulate the expression levels of cytokines (such as TNFα, IL‐1β, IL‐2, and IL‐6), and up‐regulate those of CAT, GSH‐PX, and T‐SOD, decrease that of malondialdehyde. Moreover, it also inhibited the phosphorylation of MAPKs, NF‐κB, and enhanced phosphorylation of the Nrf2 in the CP/CPPS rat model.

Discussion and Conclusions

The findings in this study suggest that lycopene exerts potent anti‐ CP/CPPS Seffects through alleviating inflammatory response and oxidative stress, which is probably attributed to the interaction of NF‐κB, MAPKs, and Nrf2 signaling pathways in rats. As a natural antioxidant, lycopene may serve as a promising pharmaceutical preparation for treating CP/CPPS.

Serum xanthophyll carotenoids are associated with estimated glomerular filtration rate in an aged cohort

Progressive renal decline is associated with increasing oxidative stress. However, the majority of studies have investigated endogenous antioxidants in predominantly advanced stages of kidney disease. Many traditional risk factors associated with renal dysfunction have been linked with cognitive decline as the kidneys and brain share comparable anatomic and haemodynamic characteristics that leave them susceptible to common pathogenic mechanisms. The objective of this study was to examine serum dietary antioxidants and their association with renal function characterised by estimated glomerular filtration rate (eGFR) in a cross-sectional analysis of 570 participants. High performance liquid chromatography quantified serum levels of retinol, α-tocopherol, γ-tocopherol and six carotenoids (α-carotene, β-carotene, β-cryptoxanthin, lutein, lycopene and zeaxanthin) in participants. Multiple regression analyses were used to evaluate associations while adjusting for potential confounders. A sensitivity analysis was performed in cognitively-intact participants only. Serum levels of the xanthophyll carotenoid lutein were positively associated with eGFR in analyses adjusted for age (years), gender, smoking, APOE4 status and Alzheimer’s disease. Retinol was inversely associated with eGFR, although was no longer significant in the smaller sensitivity analysis. Our findings identify significant associations between the xanthophyll carotenoids and eGFR. Further investigations are required to confirm these findings.

Effects of Pyrene on Human Liver HepG2 Cells: Cytotoxicity, Oxidative Stress, and Transcriptomic Changes in Xenobiotic Metabolizing Enzymes and Inflammatory Markers with Protection Trial Using Lycopene

Pyrene is one of the major polycyclic aromatic hydrocarbons formed during heat treatment of meat and in car exhausts; however, few studies have investigated pyrene-induced adverse effects on human cell lines. This study aimed at the investigation of pyrene-induced cytotoxicity and oxidative damage in human liver HepG2 cells at environmentally relevant concentrations. Pyrene-induced changes in mRNA expression of xenobiotic metabolizing enzymes (XMEs), xenobiotic transporters, antioxidant enzymes, and inflammatory markers were investigated using real-time PCR. As a protection trial, the ameliorative effects of lycopene, a carotenoid abundantly found in tomato, were investigated. The possible mechanisms behind such effects were examined via studying the co exposure effects of pyrene and lycopene on regulatory elements including the aryl hydrocarbon receptor (Air) and elytroid 2-related factor 2 (RF). The achieved results indicated that pyrene caused significant cytotoxicity at 50 n, with a clear production of reactive oxygen species (ROS) in a dose-dependent manner. Pyrene upregulated mRNA expression of phase I enzymes including CYP1A1, 1A2, and CYP1B1 and inflammatory markers including TNFα and Cox2. However, pyrene significantly downregulated phase II enzymes, xenobiotic transporters, and antioxidant enzymes. Interestingly, lycopene significantly reduced pyrene-induced cytotoxicity and ROS production. Moreover, lycopene upregulated detoxification and antioxidant enzymes, probably via its regulatory effects on Air- and RF-dependent pathways.

A randomized placebo-controlled trial to investigate the effect of lactolycopene on semen quality in healthy males

Purpose

Poor sperm quality is a major contributor to infertility in heterosexual couples, but at present there are few empirical therapies. Several studies have examined the role of dietary factors and data from randomized controlled trials suggest that oral antioxidant therapy can improve some sperm parameters. Health benefits of lycopene supplementation have been proposed for a variety of health conditions and here we examine whether it can help improve sperm quality. This study aimed to investigate the effect of 14 mg daily lactolycopene for 12 weeks on semen quality in healthy men.

Methods

Sixty healthy male participants were recruited and randomized to this double-blind, placebo-controlled parallel study and received either 14 mg/d lactolycopene or a placebo for 12 weeks. The primary endpoint was a change in motile sperm concentration. Secondary endpoints were all other aspects of sperm quality, including the level of sperm DNA damage.

Results

Fifty-six men completed the intervention and the level of plasma lycopene was significantly increased in the men randomized to receive lycopene supplementation. There was no significant change in the primary endpoint (motile sperm concentration) post-intervention (p = 0.058). However, the proportion of fast progressive sperm (p = 0.006) and sperm with normal morphology (p < 0.001) did improve significantly in response to lactolycopene intervention.

Conclusions

Supplementation with 14 mg/d lactolycopene improves sperm motility and morphology in young healthy men.

Clinical Trial Registry number and website

ISRCTN33248724 http://www.isrctn.com/ISRCTN33248724

Plant Bioactives and the Prevention of Prostate Cancer: Evidence from Human Studies

Prostate cancer has become the most common form of non-cutaneous (internal) malignancy in men, accounting for 26% of all new male visceral cancer cases in the UK. The aetiology and pathogenesis of prostate cancer are not understood, but given the age-adjusted geographical variations in prostate cancer incidence quoted in epidemiological studies, there is increasing interest in nutrition as a relevant factor. In particular, foods rich in phytochemicals have been proposed to reduce the risk of prostate cancer. Epidemiological studies have reported evidence that plant-based foods including cruciferous vegetables, garlic, tomatoes, pomegranate and green tea are associated with a significant reduction in the progression of prostate cancer. However, while there is well-documented mechanistic evidence at a cellular level of the manner by which individual dietary components may reduce the risk of prostate cancer or its progression, evidence from intervention studies is limited. Moreover, clinical trials investigating the link between the dietary bioactives found in these foods and prostate cancer have reported varied conclusions. Herein, we review the plant bioactives for which there is substantial evidence from epidemiological and human intervention studies. The aim of this review is to provide important insights into how particular plant bioactives (e.g., sulfur-containing compounds, carotenoids and polyphenols) present in commonly consumed food groups may influence the development and progression of prostate cancer.

Effects of Lycopene in Hyperoxia-Induced Lung Injury in Newborn Rats

The aim of this study was to evaluate the therapeutic effect of lycopene on a hyperoxia-induced lung injury model in rat pups. Full-term rat pups were included in the study 12-24 h after delivery. The pups were separated into 4 groups: normoxia control (NC), hyperoxia control (HC), hyperoxia + lycopene (HL), and normoxia lycopene (NL). The normoxia groups were housed in ambient air, and the hyperoxia groups in > 85% O₂. HL and NL groups received 50 mg lycopene in oil/kg body weight/day delivered intraperitoneally (i.p.), the other groups received oil alone. On day 11, the rat pups were sacrificed and their lungs removed. Statistically significant injury was observed in all histological parameters measured (MLI, proliferating cell nuclear antigen (PCNA), and apoptosis) in the HC group (HC vs NC, p = 0.001). This injury could not be reversed with lycopene treatment (HC vs HL, 0.05; NC vs HL, p = 0.001). With hyperoxia, statistically significant decreases were observed in biochemical parameters in terms of SOD, MDA, and IL-6 values (HC vs NC: SOD, p = 0.02; MDA, p = 0.043; IL-6, p = 0.001). The use of lycopene did not provide any improvement in these values (HC vs HL, p > 0.05). Hyperoxia or lycopene had no effect on IL-1β and GPx (p > 0.05). When comparing NC and NL groups, negative effects were observed in the group given lycopene in terms of MLI, PCNA, apoptosis, and IL-6 (all parameters, p = 0.001). We observed that 50 mg lycopene in oil/kg body weight/day given via i.p. had no curative effect on the hyperoxia-induced lung injury in newborn rats and may even induce adverse effects.

Genetic diversity and population structure of watermelon (Citrullus sp.) genotypes

Genetic polymorphism amid plant species is a crucial factor for plant improvement and maintaining their biodiversity. Evaluation of genetic diversity amongst plant species is significant to deal with the environmental stress conditions and their effective involvement in the breeding programs. Hence, in present study, an attempt has been made towards the genetic assessment of individual and bulked populations of 25 watermelon genotypes, belonging to Citroides (citron watermelon) and Lanatus (dessert watermelon) group from Konya, Thrace, Turkmenistan, Saudi Arabia and Turkey. The employed Random Amplified Polymorphic DNA (RAPD) and Inter-Simple Sequence Polymorphism (ISSR) marker systems provided 69.4 and 95.4% polymorphisms, respectively. Different clustering methods showed clear grouping of the genotypes based on the geographical origin and species. Citron genotypes from Turkmenistan stood apart from all the Turkish Lanatus genotypes. However, Saudi Arab Lanatus genotype grouped with native Turkish varieties indicating the genetic linkage. Among all the Turkmenistan Citron genotypes, Turkmenistan-11 was the most distinct form. Moreover, sufficient genetic variation was found between the commercial and native Lanatus genotypes of Turkey as well as Citron genotypes of Turkmenistan. Hence, it will be beneficial to include these genotypes in the future breeding programs to transfer disease-resistant alleles from Citron to Lanatus genotypes.

Lycopene Ameliorated Oxidative Stress and Inflammation in Type 2 Diabetic Rats

We aim to study the antioxidative and anti-inflammatory effects of lycopene on type 2 diabetes mellitus (T2DM) rats, anticipating a complementary strategy for the prevention of long-term complications of T2DM. In this study, rats with streptozotocin-induced diabetes were divided into four groups, receiving a 10-week lycopene intervention: DM, DM + low dose of lycopene (L), DM + medium dose of lycopene (M), and DM + high dose of lycopene (H) group with 0, 5, 10, and 15 mg/kg BW lycopene, respectively. At the end of intervention, fasted blood glucose (FBG) level, oxidative stress indicators, including glycosylated hemoglobin (GHb), glycosylated low-density lipoprotein, oxidized low-density lipoprotein (ox-LDL). and malondialdehyde (MDA), as well as antioxidants, that is, catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx), and inflammatory factors like tumor necrosis factor-α (TNF-α) and C-reactive protein (CRP) were determined. The results indicated that oxidative stress and inflammatory factors were elevated in DM rats. Lycopene intervention decreased the FBG level in DM rats compared with the untreated ones. It revealed a dose-dependent effect on decreasing serum oxidative stress biomarkers, including GHb, ox-LDL, and MDA. Inflammatory factors (TNF-α and CRP) in DM rats were also decreased by lycopene intervention. Total antioxidative capacity as well as the activities of antioxidants in DM rats including CAT, SOD, and GPx were increased after lycopene intervention. We conclude that lycopene protects against diabetic progression and prevents further complications of diabetic rats through ameliorating oxidative stress and inflammation, as well as improving the systemic antioxidative capacity. PRACTICAL APPLICATION: According to our study, lycopene intakes at experimental dosages appear to have beneficial effects on ameliorating oxidative stress and inflammation in type 2 diabetes mellitus (T2DM) rats, suggesting that lycopene might help improving T2DM progression when its daily intake is up to about 0.79 mg/kg BW in humans, which approximately equals to 5 mg/kg BW in rats. However, more clinical trials are needed to provide a more reliable and convincing conclusion in humans.

Analysis of Tomato Carotenoids: Comparing Extraction and Chromatographic Methods

Background: Tomatoes (Solanum lycopersicum) are an economically and nutritionally important crop colored by carotenoids such as lycopene and β-carotene. Market diversification and interest in the health benefits of carotenoids has created the desire in plant, food, and nutritional scientists for improved extraction and quantification protocols that avoid the analytical bottlenecks caused by current methods. Objective: Our objective was to compare standard and rapid extraction as well as chromatographic separation methods for tomato carotenoids. Method: Comparison was based on accuracy and the ability to discriminate between alleles and genetic backgrounds. Estimates of the contribution to variance in the presence of genetic and environmental effects were further used for comparison. Selections of cherry and processing tomatoes with varying carotenoid profiles were assessed using both established extraction and HPLC-diode array detector (HPLC-DAD) methods and rapid extraction and ultra-HPLC-DAD (UHPLC-DAD) protocols. Results: Discrimination of alleles in samples extracted rapidly (<5 min/sample) was similar to samples extracted using a standard method (10 min/sample), although carotenoid concentrations were lower due to reduced extraction efficiency. Quantification by HPLC-DAD (21.5 min/sample) and UHPLC-DAD (4.2 min/sample) were comparable, but the UHPLC-DAD method could not separate all carotenoids and isomers of tangerine tomatoes. Random effects modeling indicated that extraction and chromatographic methods explained a small proportion of variance compared with genetic and environmental sources. Conclusions: The rapid extraction and UHPLC-DAD methods could enhance throughput for some applications compared with standard protocols.

Lycopene attenuates aluminum-induced hippocampal lesions by inhibiting oxidative stress-mediated inflammation and apoptosis in the rat

Aluminum (Al) causes hippocampal lesions by oxidative stress, which is widely accepted as the primary pathogenesis of Al neurotoxicity. Lycopene (LYC), a naturally carotenoid, has received extensive attention due to its antioxidant effect. In this study, the neuroprotective effects and mechanisms of LYC against aluminum chloride (AlCl₃)-induced hippocampal lesions were explored. First, oral administration of LYC (4 mg/kg) alleviated AlCl₃-induced (150 mg/kg) cognition impairment and histopathological changes of the hippocampus in rats. Then, LYC significantly attenuated AlCl₃-induced oxidative stress, presenting as the reduced reactive oxygen species, malondialdehyde and 8-hydroxy-2'-deoxyguanosine levels, and increased glutathione level and superoxide dismutase activity. Moreover, LYC also protected the hippocampus from AlCl₃-induced apoptosis and neuroinflammation, as assessed by protein levels of p53, Bcl-2-associated X protein (Bax), B-cell lymphoma gene 2 (Bcl-2), Cytochrome c (Cyt c), cleaved caspase-3 and nuclear factor kappa B, as well as the mRNA levels of Bax, Bcl-2, tumor necrosis factor alpha, interleukin-6 and interleukin-1 beta. Finally, LYC increased nuclear factor-erythroid-2-related factor 2 (Nrf2) nuclear translocation and its downstream gene expression, including heme oxygenase-1, NAD(P)H: quinone oxidoreductase 1, glutamate cysteine ligase catalytic subunit and superoxide dismutase 1, which were involved in antioxidant, anti-apoptosis, and anti-inflammation. Overall, our findings demonstrate LYC attenuates Al-induced hippocampal lesions by inhibiting oxidative stress-mediated inflammation and apoptosis in the rat.

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.

Let food be your medicine: nutraceutical properties of lycopene

In this review, we highlight research and clinical trials involving lycopene and its impact on human health.

Tomato lycopene prevention of alcoholic fatty liver disease and hepatocellular carcinoma development

Alcoholic liver disease (ALD) is a major cause of morbidity and mortality worldwide. The incidence of hepatocellular carcinoma (HCC) is increasing in the United States, and chronic, excessive alcohol consumption is responsible for 32%–45% of all the liver cancer cases in the United States. Avoidance of chronic or excessive alcohol intake is the best protection against alcohol-related liver injury; however, the social presence and addictive power of alcohol are strong. Induction of the cytochrome P450 2E1 (CYP2E1) enzyme by chronic and excessive alcohol intake is known to play a role in the pathogenesis of ALD. High intake of tomatoes, rich in the carotenoid lycopene, is associated with a decreased risk of chronic disease. The review will overview the prevention of ALD and HCC through dietary tomato rich in lycopene as an effective intervention strategy and the crucial role of CYP2E1 induction as a molecular target. The review also indicates a need for caution among individuals consuming both alcohol and high dose lycopene as a dietary supplement.

Dietary Tomato Powder Inhibits High-Fat Diet-Promoted Hepatocellular Carcinoma with Alteration of Gut Microbiota in Mice Lacking Carotenoid Cleavage Enzymes

Both incidence and death rate due to liver cancer have increased in the United States. Higher consumption of lycopene-rich tomato and tomato products is associated with a decreased risk of cancers. β-Carotene-15, 15'-oxygenase (BCO1), and β-carotene-9', 10'-oxygenase (BCO2) cleave lycopene to produce bioactive apo-lycopenoids. Although BCO1/BCO2 polymorphisms affect human and animal lycopene levels, whether dietary tomato consumption can inhibit high-fat diet (HFD)-promoted hepatocellular carcinoma (HCC) development and affect gut microbiota in the absence of BCO1/BCO2 is unclear. BCO1/BCO2 double knockout mice were initiated with a hepatic carcinogen (diethylnitrosamine) at 2 weeks of age. At 6 weeks of age, the mice were randomly assigned to an HFD (60% of energy as fat) with or without tomato powder (TP) feeding for 24 weeks. Results showed that TP feeding significantly decreased HCC development (67%, 83%, and 95% reduction in incidence, multiplicity, and tumor volume, respectively, P < 0.05). Protective effects of TP feeding were associated with (1) decreased hepatic inflammatory foci development and mRNA expression of proinflammatory biomarkers (IL1β, IL6, IL12α, monocyte chemoattractant protein-1, and inducible NO synthase); (2) increased mRNA expression of deacetylase sirtuin 1 and nicotinamide phosphoribosyltransferase involving NAD⁺ production; and (3) increased hepatic circadian clock genes (circadian locomotor output cycles kaput, period 2, and cryptochrome-2, Wee1). Furthermore, TP feeding increased gut microbial richness and diversity, and significantly decreased the relative abundance of the genus Clostridium and Mucispirillum, respectively. The present study demonstrates that dietary tomato feeding independent of carotenoid cleavage enzymes prevents HFD-induced inflammation with potential modulating gut microbiota and inhibits HFD-promoted HCC development.

De novo domestication of wild tomato using genome editing

Breeding of crops over millennia for yield and productivity has led to reduced genetic diversity. As a result, beneficial traits of wild species, such as disease resistance and stress tolerance, have been lost. We devised a CRISPR-Cas9 genome engineering strategy to combine agronomically desirable traits with useful traits present in wild lines. We report that editing of six loci that are important for yield and productivity in present-day tomato crop lines enabled de novo domestication of wild Solanum pimpinellifolium. Engineered S. pimpinellifolium morphology was altered, together with the size, number and nutritional value of the fruits. Compared with the wild parent, our engineered lines have a threefold increase in fruit size and a tenfold increase in fruit number. Notably, fruit lycopene accumulation is improved by 500% compared with the widely cultivated S. lycopersicum. Our results pave the way for molecular breeding programs to exploit the genetic diversity present in wild plants.

Comparing Characteristics of Root, Flour and Starch of Biofortified Yellow-Flesh and White-Flesh Cassava Variants, and Sustainability Considerations: A Review

Cassava is a significant food security and industrial crop, contributing as food, feed and industrial biomass in Africa, Asia and South America. Breeding efforts have led to the development of cassava variants having desirable traits such as increased root, flour, and starch yield, reduced toxicity, reduced pest/disease susceptibility and improved nutrient contents. Prominent among those breeding efforts is the development of colored-flesh cassava variants, especially biofortified yellow-fleshed ones, with increased pro-vitamin A carotenoids, compared to the white-flesh variants. The concept of sustainability in adoption of biofortified yellow-flesh cassava and its products cannot be fully grasped without some detailed information on its properties and how these variants compare to those of the white-flesh cassava. Flour and starch are highly profitable food products derived from cassava. Cassava roots can be visually distinguished based on flesh color and other physical properties, just as their flours and starches can be differentiated by their macro- and micro-properties. The few subtle differences that exist between cassava variants are identified and exploited by consumers and industry. Although white-flesh variants are still widely cultivated, value addition offered by biofortified yellow-flesh variants may strengthen acceptance and widespread cultivation among farmers, and, possibly, cultivation of biofortified yellow-flesh variants may outpace that of white-flesh variants in the future. This review compares properties of cassava root, flour, and starch from white-flesh and biofortified yellow-flesh variants. It also states the factors affecting the chemical, functional, and physicochemical properties; relationships between the physicochemical and functional properties; effects of processing on the nutritional properties; and practical considerations for sustaining adoption of the biofortified yellow-flesh cassava.

Nano-liposomes of lycopene reduces ischemic brain damage in rodents by regulating iron metabolism

In order to discover new drug delivery approaches and to understand the mechanism of iron overload in cerebral ischemia/reperfusion (I/R), we aimed to investigate the effects of lycopene (LYC) in the form of nano-liposomes (L-LYC) on iron-regulating proteins and ischemic brain injury. We found that L-LYC significantly increased the LYC content in serum and the brain. Adult male Sprague-Dawley rats treated with L-LYC for 14 days were subjected to 60 min of ischemia and 7 days of reperfusion. The effects of L-LYC were evaluated by infarction volume, neurological score, neuronal apoptosis, and markers for oxidative stress. Levels of iron-regulating protein such as hepcidin and ferroportin (FPN1) were examined. L-LYC reduced cerebral infarction and improved neurobehavior of the rats more efficiently than "naked" LYC. L-LYC reduced protein levels of oxidases (e.g. nitric oxide synthase and NOX2), increased the level of Bcl-2, lowered caspase-3, and suppressed apoptosis through inhibiting MAPK-JNK. Furthermore, L-LYC suppressed hepcidin-mediated decrease in FPN1, a sole iron exporter, and normalized the levels of iron. We further demonstrated that the effect of L-LYC on hepcidin expression might result from its ability to attenuate the release of the inflammatory factor interleukin 6. The results demonstrated that nano-liposomal encapsulation significantly improved LYC efficacy in providing neuronal protection against I/R injury. The data also revealed a novel mechanism of L-LYC's neuroprotection by regulating iron metabolism in an ischemic brain.

Lycopene treatment inhibits activation of Jak1/Stat3 and Wnt/β-catenin signaling and attenuates hyperproliferation in gastric epithelial cells

Helicobacter pylori (H pylori) colonizes the human stomach and increases the risk of gastric diseases including gastric cancer. H pylori increases reactive oxygen species (ROS), which activate Janus-activator kinase 1 (Jak1)/signal transducers and activators of transcription 3 (Stat3) in gastric epithelial cells. ROS mediate hyperproliferation, a hallmark of carcinogenesis, by activating Wnt/β-catenin signaling in various cells. Lycopene is a potent antioxidant exhibiting anticancer effects. We hypothesized that lycopene may inhibit H pylori-induced hyperproliferation by suppressing ROS-mediated activation of Jak1/Stat3 and Wnt/β-catenin signaling, and β-catenin target gene expression in gastric epithelial cells. We determined cell viability, ROS levels, and the protein levels of phospho- and total Jak1/Stat3, Wnt/β-catenin signaling molecules, Wnt-1, lipoprotein-related protein 5, and β-catenin target oncogenes (c-Myc and cyclin E) in H pylori-infected gastric epithelial AGS cells. The Jak1/Stat3 inhibitor AG490 served as the control treatment. The significance of the differences among groups was calculated using the 1-way analysis of variance followed by Newman-Keuls post hoc tests. The results show that lycopene reduced ROS levels and inhibited Jak1/Stat3 activation, alteration of Wnt/β-catenin multiprotein complex molecules, expression of c-Myc and cyclin E, and cell proliferation in H pylori-infected AGS cells. AG490 similarly inhibited H pylori-induced cell proliferation, alteration of Wnt/β-catenin multiprotein complex molecules, and oncogene expression. H pylori increased the levels of Wnt-1 and its receptor lipoprotein-related protein 5; this increase was inhibited by either lycopene or AG490 in AGS cells. In conclusion, lycopene inhibits ROS-mediated activation of Jak1/Stat3 and Wnt/β-catenin signaling and, thus, oncogene expression in relation to hyperproliferation in H pylori-infected gastric epithelial cells. Lycopene might be a potential and promising nutrient for preventing H pylori-associated gastric diseases including gastric cancer.

Engineering membrane morphology and manipulating synthesis for increased lycopene accumulation in Escherichia coli cell factories

The goal of this work was to improve the lycopene storage capacity of the E. coli membrane by engineering both morphological and biosynthetic aspects. First, Almgs, a protein from Acholeplasma laidlawii that is involved in membrane bending is overexpressed to expand the storage space for lycopene, which resulted in a 12% increase of specific lycopene production. Second, several genes related to the membrane-synthesis pathway in E. coli, including plsb, plsc, and dgka, were also overexpressed, which led to a further 13% increase. In addition, membrane separation and component analysis confirmed that the increased amount of lycopene was mainly accumulated within the cell membranes. Finally, by integrating both aforementioned modification strategies, a synergistic effect could be observed which caused a 1.32-fold increase of specific lycopene production, from the 27.5 mg/g of the parent to 36.4 mg/g DCW in the engineered strain. This work demonstrates that membrane engineering is a feasible strategy for increasing the production and accumulation of lycopene in E. coli.

Identification of an Epoxide Metabolite of Lycopene in Human Plasma Using 13C-Labeling and QTOF-MS

The carotenoid lycopene is a bioactive component of tomatoes and is hypothesized to reduce risk of several chronic diseases, such as prostate cancer. The metabolism of lycopene is only beginning to be understood and some studies suggest that metabolites of lycopene may be partially responsible for bioactivity associated with the parent compound. The detection and characterization of these compounds in vivo is an important step in understanding lycopene bioactivity. The metabolism of lycopene likely involves both chemical and enzymatic oxidation. While numerous lycopene metabolites have been proposed, few have actually been identified in vivo following lycopene intake. Here, LC-QTOF-MS was used along with ¹³C-labeling to investigate the post-prandial oxidative metabolism of lycopene in human plasma. Previously reported aldehyde cleavage products were not detected, but a lycopene 1,2-epoxide was identified as a new candidate oxidative metabolite.

Serum Lycopene Concentrations and Associations with Clinical Outcomes in a Cohort of Maternal-Infant Dyads

Oxidative stress has been associated with adverse neonatal outcomes, and many carotenoids, including lycopene, potentially have antioxidant properties. The objective of this analysis was to explore the associations between serum lycopene concentrations, including lycopene isomers, and maternal-newborn outcomes. Maternal and cord blood samples were collected in 180 mother-infant pairs. Serum of total lycopene as well as the cis- and trans-isomers concentrations were measured using HPLC (High Performance Liquid Chromatography). Descriptive statistics were calculated; Spearman coefficients were used to assess correlations between maternal and cord concentrations. The relationship between lycopene concentration and outcomes were evaluated with linear and logistic regression models, with adjustment for relevant confounders. A p ≤ 0.05 was considered statistically significant. Maternal and cord serum lycopene concentrations were positively correlated for total lycopene (r = 0.30, p < 0.0001), cis-lycopene (r = 0.29, p = 0.0002); and trans-lycopene (r = 0.32, p < 0.0001). Maternal concentrations of cis-lycopene were significantly lower in mothers whose infants developed respiratory distress syndrome compared to those who did not (0.336 ± 0.171 vs. 0.445 ± 0.238 µmol/L, p = 0.04) and also in mothers whose babies were admitted to the newborn intensive care unit compared to those who were not (0.380 ± 0.202 vs. 0.458 ± 0.244 µmol/L, p = 0.04). Conversely, cord concentrations of trans-lycopene were significantly higher in infants who developed RDS (Respiratory Distress Syndrome) (0.023 ± 0.012 vs. 0.016 ± 0.012, p = 0.007 for RDS vs. no RDS), and a similar pattern was seen NICU admission (0.023 ± 0.016 vs. 0.015 ± 0.009 µmol/L for NICU (Newborn Intensive Care Unit) admission vs. no NICU admission, p = 0.007). Maternal concentrations of total and cis-lycopene were positively associated with infant birth weight, length and head circumference after adjustment for relevant confounders. As serum carotenoids, including lycopene, are modifiable by diet, future research determining the clinical impact of these compounds is warranted.

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.

Lycopene Inhibits Metastasis of Human Liver Adenocarcinoma SK-Hep-1 Cells by Downregulation of NADPH Oxidase 4 Protein Expression

NADPH oxidase 4 (NOX4), with the sole function to produce reactive oxygen species (ROS), can be a molecular target for disrupting cancer metastasis. Several studies have indicated that lycopene exhibited anti-metastatic actions in vitro and in vivo. However, the role of NOX4 in the anti-metastatic action of lycopene remains unknown. Herein, we first confirmed the anti-metastatic effect of lycopene (0.1-5 μM) on human liver adenocarcinoma SK-Hep-1 cells. We showed that lycopene significantly inhibited NOX4 protein expression, with the strongest inhibition of 64.3 ± 10.2% (P < 0.05) at 2.5 μM lycopene. Lycopene also significantly inhibited NOX4 mRNA expression, NOX activity, and intracellular ROS levels in SK-Hep-1 cells. We then determined the effects of lycopene on transforming growth factor β (TGF-β)-induced metastasis. We found that TGF-β (5 ng/mL) significantly increased migration, invasion, and adhesion activity, the intracellular ROS level, matrix metalloproteinase 9 (MMP-9) and MMP-2 activities, the level of NOX4 protein expression, and NOX activity. All these TGF-β-induced effects were antagonized by the incubation of SK-Hep-1 cells with lycopene (2.5 μM). Using transient transfection of siRNA against NOX4, we found that the downregulation of NOX4 could mimic lycopene by inhibiting cell migration and the activities of MMP-9 and MMP-2 during the incubation with or without TGF-β on SK-Hep-1 cells. The results demonstrate that the downregulation of NOX4 plays a crucial role in the anti-metastatic action of lycopene in SK-Hep-1 cells.

Combination of EPA with Carotenoids and Polyphenol Synergistically Attenuated the Transformation of Microglia to M1 Phenotype Via Inhibition of NF-κB

Microglia activation toward the M1 phenotype has been reported to contribute to the neurodegenerative processes and cognition alterations due to the release of pro-inflammatory mediators and cytokines. The aim of the present research was to assess the effectiveness of free fatty acids omega-3 preparations: eicosapentaenoic acid (EPA) or/and docosahexaenoic acid (DHA), carotenoids and phenolics combinations, in inhibiting the release of inflammatory mediators from activated microglia. Preincubation of BV-2 microglia cells with each of the FFAs omega-3 preparations in a range of 0.03-2 μM together with Lyc-O-mato^® (0.1 μM), Carnosic acid (0.2 μM) with or without Lutein (0.2 μM), 1 h before addition of lipopolysaccharide (LPS) for 16 h caused a synergistic inhibition of nitric oxide (NO) production with a rank order of EPA > Ropufa (EPA/DHA 2/1) > Krill (EPA/DHA 1.23/1). The optimal inhibitory combinations of EPA (0.125 μM) with the phytonutrients caused a synergistic inhibition of prostaglandin E₂ (PGE₂) release, IL-6 secretion, superoxide and NO production and prevention of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) upregulation and elevated CD40 expression in microglia exposed to LPS or interferon-γ (IFN-γ), representing infection or inflammation, respectively. The presence of the combination caused a synergistic increase in the release of the anti-inflammatory cytokine IL-10. The inhibitory effects by the combinations of EPA with the phytonutrients were mediated by the inhibition of the redox-sensitive NF-κB activation and detected by its phosphorylated p-65 on serine 536 in microglia stimulated by either LPS or IFN-γ. In addition, phosphorylated CREB on serine 133 which was shown to be involved in the induction of iNOS was inhibited by the combinations in stimulated cells. In conclusion, the results suggest that low concentrations of EPA with the phytonutrients are very efficient in inhibiting the transformation of microglia to M1 phenotype and may prevent cognition deficit.

Synthesis of apo-13- and apo-15-lycopenoids, cleavage products of lycopene that are retinoic acid antagonists

Consumption of the tomato carotenoid, lycopene, has been associated with favorable health benefits. Some of lycopene's biological activity may be due to metabolites resulting from cleavage of the lycopene molecule. Because of their structural similarity to the retinoic acid receptor (RAR) antagonist, β-apo-13-carotenone, the "first half" putative oxidative cleavage products of the symmetrical lycopene have been synthesized. All transformations proceed in moderate to good yield and some with high stereochemical integrity allowing ready access to these otherwise difficult to obtain terpenoids. In particular, the methods described allow ready access to the trans isomers of citral (geranial) and pseudoionone, important flavor and fragrance compounds that are not readily available isomerically pure and are building blocks for many of the longer apolycopenoids. In addition, all of the apo-11, apo-13, and apo-15 lycopenals/lycopenones/lycopenoic acids have been prepared. These compounds have been evaluated for their effect on RAR-induced genes in cultured hepatoma cells and, much like β-apo-13-carotenone, the comparable apo-13-lycopenone and the apo-15-lycopenal behave as RAR antagonists. Furthermore, molecular modeling studies demonstrate that the apo-13-lycopenone efficiently docked into the ligand binding site of RARα. Finally, isothermal titration calorimetry studies reveal that apo-13-lycopenone acts as an antagonist of RAR by inhibiting coactivator recruitment to the receptor.

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.

Yields and Nutritional of Greenhouse Tomato in Response to Different Soil Aeration Volume at two depths of Subsurface drip irrigation

This study investigated the effects of 4 aeration levels (varied by injection of air to the soil through subsurface irrigation lines) at two subsurface irrigation line depths (15 and 40 cm) on plant growth, yield and nutritional quality of greenhouse tomato. In all experiments, fruit number, width and length, yield, vitamin C, lycopene and sugar/acid ratio of tomato markedly increased in response to the aeration treatments. Vitamin C, lycopene, and sugar/acid ratio increased by 41%, 2%, and 43%, respectively, in the 1.5 times standard aeration volume compared with the no-aeration treatment. An interaction between aeration level and depth of irrigation line was also observed with yield, fruit number, fruit length, vitamin C and sugar/acid ratio of greenhouse tomato increasing at each aeration level when irrigation lines were placed at 40 cm depth. However, when the irrigation lines were 15 cm deep, the trend of total fruit yields, fruit width, fruit length and sugar/acid ratio first increased and then decreased with increasing aeration level. Total soluble solids and titrable acid decreased with increasing aeration level both at 15 and 40 cm irrigation line placement. When all of the quality factors, yields and economic benefit are considered together, the combination of 40 cm line depth and "standard" aeration level was the optimum combination.

Hepatoprotective and antioxidant effects of lycopene on non-alcoholic fatty liver disease in rat

AIM

To evaluate the hepatoprotective effect of lycopene (Ly) on non-alcoholic fatty liver disease (NAFLD) in rat.

METHODS

A rat model of NAFLD was first established by feeding a high-fat diet for 14 wk. Sixty-five rats were randomly divided into normal group, model group and Ly treatment groups. Alanine aminotransferase (ALT), aspartate aminotransferase (AST), triglycerides (TG), total cholesterol (TC) in serum and low density lipoprotein-cholesterol (LDL-C), high density lipoprotein-cholesterol (HDL-C), free fatty acid (FFA), malondialdehyde (MDA), superoxide dismutase (SOD), glutathione (GSH) in liver tissue were evaluated, respectively. While the hepatoprotective effect was also confirmed by histopathological analysis, the expression levels of TNF-α and cytochrome P₄₅₀ (CYP) 2E1 in rat liver were determined by immunohistochemistry analysis.

RESULTS

A significant decrease was observed in the levels of serum AST (2.07-fold), ALT (2.95-fold), and the blood lipid TG (2.34-fold) and TC (1.66-fold) in the dose of 20 mg/kg Ly-treated rats (P < 0.01), compared to the model group. Pretreatment with 5, 10 and 20 mg/kg of Ly significantly raised the levels of antioxidant enzyme SOD in a dose-dependent manner, to 90.95 ± 9.56, 109.52 ± 11.34 and 121.25 ± 10.68 (P < 0.05, P < 0.01), as compared with the model group. Similarly, the levels of GSH were significantly increased (P < 0.05, P < 0.01) after the Ly treatment. Meanwhile, pretreatment with 5, 10 and 20 mg/kg of Ly significantly reduced MDA amount by 30.87, 45.51 and 54.49% in the liver homogenates, respectively (P < 0.01). The Ly treatment group showed significantly decreased levels of lipid products LDL-C (P < 0.05, P < 0.01), improved HDL-C level and significantly decreased content of FFA, compared to the model group (P < 0.05, P < 0.01). Furthermore, the Ly-treated group also exhibited a down-regulated TNF-α and CYP2E1 expression, decreased infiltration of liver fats and reversed histopathological changes, all in a dose-dependent manner (P < 0.05, P < 0.01).

CONCLUSION

This study suggests that Ly has a protective effect on NAFLD, down-regulates expression of TNF-α, and that CYP2E1 may be one of the action mechanisms for Ly.

Tomato cystine-knot miniproteins possessing anti-angiogenic activity exhibit in vitro gastrointestinal stability, intestinal absorption and resistance to food industrial processing

The cystine-knot miniproteins present in tomato fruit (TCMPs) have been shown to exert anti-angiogenic effects by inhibiting endothelial cell migration and to display resistance to gastrointestinal proteolytic attack. To better define the pharmacological potential of TCMPs, their oral bioavailability and their resistance to industrial processing must be assessed. To explore the intestinal transport of TCMPs we used the differentiated Caco-2 cells model. After 24h incubation, 37.73±9.34% of TCMPs crossed the epithelium, without altering the integrity of the cell layer. To assess the effects of the industrial processing on the biochemical features and the biological activity of TCMPs, we developed a method for purifying the proteins from tomato paste. The tomato-paste purified TCMPs retained the resistance to gastrointestinal digestion and the inhibitory activity towards endothelial cell migration. Our previous and present results collectively demonstrate that TCMPs possess interesting features for drug development.

Cardiovascular benefits of lycopene: fantasy or reality?

Epidemiological evidence indicates that high consumption of tomatoes and tomato-based products reduces the risk of chronic diseases such as CVD and cancer. Such potential benefits are often ascribed to high concentrations of lycopene present in tomato products. Mainly from the results of in vitro studies, potential biological mechanisms by which carotenoids could protect against heart disease and cancer have been suggested. These include cholesterol reduction, inhibition of oxidation processes, modulation of inflammatory markers, enhanced intercellular communication, inhibition of tumourigenesis and induction of apoptosis, metabolism to retinoids and antiangiogenic effects. However, with regard to CVD, results from intervention studies gave mixed results. Over fifty human intervention trials with lycopene supplements or tomato-based products have been conducted to date, the majority being underpowered. Many showed some beneficial effects but mostly on non-established cardiovascular risk markers such as lipid peroxidation, DNA oxidative damage, platelet activation and inflammatory markers. Only a few studies showed improvement in lipid profiles, C reactive protein and blood pressure. However, recent findings indicate that lycopene could exert cardiovascular protection by lowering HDL-associated inflammation, as well as by modulating HDL functionality towards an antiatherogenic phenotype. Furthermore, in vitro studies indicate that lycopene could modulate T lymphocyte activity, which would also inhibit atherogenic processes and confer cardiovascular protection. These findings also suggest that HDL functionality deserves further consideration as a potential early marker for CVD risk, modifiable by dietary factors such as lycopene.

Carotenoids as biomarkers of fruit and vegetable intake in men and women

High fruit and vegetable (FAV) intake is associated with a lower prevalence of chronic diseases. Identifying the ideal number of FAV servings needed to reduce chronic disease risk is, however, difficult because of biases inherent to common self-report dietary assessment tools. The aim of our study was to examine the associations between daily FAV intake and plasma carotenoid concentrations in men and women enrolled in a series of fully controlled dietary interventions. We compiled and analysed data from a group of 155 men and 109 women who participated in six fully controlled dietary interventions and compared post-intervention fasting plasma carotenoid (α-carotene,β-carotene,β-cryptoxanthin, lutein, lycopene, zeaxanthin) concentrations with regard to the daily FAV servings consumed by the participants. We found that plasmaβ-cryptoxanthin, lutein and zeaxanthin concentrations were positively associated with daily FAV servings (P≤0·005). However, daily FAV intake was negatively associated with plasmaα-carotene (P<0·0005) and lycopene (P<0·0001) concentrations, whereas no association was noted with plasmaβ-carotene. When men and women were analysed separately, we found that for any given number of FAV servings consumed women had higher circulating lutein concentrations compared with men (P<0·01). Significant sex×FAV (P<0·0001) and sex×dietaryβ-cryptoxanthin (P<0·0005) interactions were also noted favouring higher plasmaβ-cryptoxanthin concentrations in women than in men for a given FAV consumption. Results from these fully controlled dietary feeding studies indicate that plasmaβ-cryptoxanthin and lutein concentrations can be used as robust biomarkers of FAV consumption. They also suggest the existence of sex differences influencing circulatingβ-cryptoxanthin and lutein concentrations following FAV consumption.

β-Carotene Inhibits Tumor-Specific Angiogenesis by Altering the Cytokine Profile and Inhibits the Nuclear Translocation of Transcription Factors in B16F-10 Melanoma Cells

Angiogenesis is the formation of new blood vessels out of the preexisting vascular network and involves a sequence of events that are of key importance in a broad array of physiological and pathological processes. The growth of tumor and metastasis are dependent on the formation of new blood vessels. The present study therefore aims at evaluating the antiangiogenic effect of β-carotene using in vivo and in vitro models. Male C57BL/6 mice as well as B16F-10 cells were used for the experimental study. The in vivo study includes the inhibitory effect of β-carotene on the formation of tumor-directed capillaries. Rat aortic ring assay, human umbilical vein endothelial cell proliferation, migration, and tube formation are used for assessing the in vitro antiangiogenic effect of β-carotene. The differential regulation of proinflammatory cytokines as well as the inhibitory effect of β-carotene on the activation and nuclear translocation of transcription factors are also assessed. β-Carotene treatment significantly reduces the number of tumor-directed capillaries accompanied by altered serum cytokine levels. β-Carotene is able to inhibit proliferation, migration, and tube formation of endothelial cells. β-Carotene treatment downregulates the expression of matrix metalloproteinase (MMP)—2, MMP-9, prolyl hydroxylase, and lysyl oxidase gene expression and upregulates the expression of tissue inhibitor of metalloproteinase (TIMP)—1 and TIMP-2. The study reveals that β-carotene treatment could alter proinflammatory cytokine production and could inhibit the activation and nuclear translocation of p65, p50, c-Rel subunits of nuclear factor-κ B, and other transcription factors such as c-fos, activated transcription factor-2, and cyclic adenosine monophosphate response element—binding protein in B16F-10 melanoma cells. These observations show that β -carotene exerts its antiangiogenic effect by altering the cytokine profile and could inhibit the activation and nuclear translocation of transcription factors.