Serum carotenoids and atherosclerosis. The Rotterdam Study

Association between ischemic heart disease and dietary intake of lycopene: a case-control study

Aim

The effect of dietary lycopene on ischemic heart disease (IHD) is not clear. Hence, this study aimed to determine the association between dietary lycopene and IHD.

Methods

This case-control study was conducted on 443 patients with physician confirmed diagnosis of IHD as the case group and 443 healthy individuals as the control group. Data on demographic, medical history, anthropometric, and physical activity of the participants were collected. Food intake was evaluated using a 237-item semi-quantitative food frequency questionnaire (FFQ). The dietary intake of lycopene was assessed using Nutritionist IV software.

Results

A negative association was found between IHD and lycopene (OR: 0.98, CI 95%: 0.963-0.996, p = 0.02). The results remained significant after adjustment for age and sex, additional adjustment for dietary intake of calorie and fat, further adjustments for BMI, and additional adjustment for smoking, drinking alcohol, and physical activity. The risk of IHD in people with the highest quartile of dietary intake of lycopene was significantly lower than those with the lowest quartile (OR = 0.67, CI 95%: 0.46-0.97, p = 0.036).

Conclusion

There was a significant inverse relationship between intake of lycopene and IHD. Further prospective studies in different populations are required to elucidate the roles of lycopene against IHD.

Identification of dietary components in association with abdominal aortic calcification

The precise impact of dietary components on vascular health remains incompletely understood. To identify the dietary components and their associations with abdominal aortic calcification (AAC), the data from NHANES was employed in this cross-sectional study. The LASSO method and logistic regression were utilized to identify dietary components that exhibited the strongest association with AAC. Grouped WQS regression analysis was employed to evaluate the combined effects of dietary components on AAC. Furthermore, principal component analysis was employed to identify the primary dietary patterns in the study population. The present analysis included 1862 participants, from whom information on 35 dietary macro- and micronutrient components was obtained through 24-hour dietary recall interviews. The assessment of AAC was performed utilizing dual-energy X-ray absorptiometry. The LASSO method identified 10 dietary components that were associated with AAC. Total protein, total fiber, vitamin A, and β-cryptoxanthin exhibited a negative association with AAC. Compared to the first quartile, the adjusted odds ratios (95% CIs) for the highest quartile were 0.59 (0.38, 0.93), 0.63 (0.42, 0.93), 0.59 (0.41, 0.84), and 0.68 (0.48, 0.94), respectively. Grouped WQS regression demonstrated a positive association between the lipid group and AAC (aOR: 1.29; 95% CI: 1.12, 1.50), while the proteins and phytochemical group exhibited a negative association with AAC (aOR: 0.69; 95% CI: 0.58, 0.82). For the dietary pattern analysis, high adherence to the plant-based pattern (aOR: 0.62; 95% CI: 0.44, 0.88) was associated with a lower risk of AAC, whereas the caffeine and theobromine pattern (aOR: 1.73; 95% CI: 1.25, 2.41) was associated with a higher risk of AAC. The findings of this study indicate that adopting a dietary pattern characterized by high levels of protein and plant-based foods, as well as reduced levels of fat, may offers potential advantages for the prevention of AAC.

Lycopene Ameliorates Hypoxic Pulmonary Hypertension via Suppression of Oxidative Stress

Hypoxic pulmonary hypertension (HPH) is a progressive cardiopulmonary system disease characterized by pulmonary vascular remodeling. Its occurrence and progression are closely related to oxidative stress. Lycopene, extracted from red vegetables and fruits, exhibits a particularly high antioxidant capacity that is beneficial for cardiovascular diseases. Nevertheless, the role and mechanism of lycopene in HPH remain unknown. Here, we found that lycopene reversed the elevated right ventricular systolic pressure (RVSP), right ventricular hypertrophy, and pulmonary vascular remodeling induced by hypoxia in rats. In vitro, lycopene caused lower proliferation and migration of PASMCs, with higher apoptosis. Consistent with the antiproliferative result of lycopene on hypoxic PASMCs, the hippo signaling pathway associated with cell growth was activated. Furthermore, lycopene reduced malondialdehyde (MDA) levels and enhanced superoxide dismutase (SOD) activity in the lungs and serum of rats under hypoxia conditions. The expression of NOX4 in the lungs was also significantly decreased. Hypoxic PASMCs subjected to lycopene showed decreased reactive oxygen species (ROS) production and NOX4 expression. Importantly, lycopene repressed HIF-1α expression both in the lungs and PASMCs in response to hypoxia in the absence of a significant change of HIF-1α mRNA. Compared with 2ME2 (a HIF-1α inhibitor) alone treatment, lycopene treatment did not significantly change PASMC proliferation, NOX4 expression, and ROS production after 2ME2 blocked HIF-1α, suggesting the inhibitory effect of lycopene on HIF-1α-NOX4-ROS axis and the targeted effect on HIF-1α. After CHX blocked protein synthesis, lycopene promoted the protein degradation of HIF-1α. MG-132, a proteasome inhibitor, notably reversed the decrease in HIF-1α protein level induced by lycopene in response to hypoxia. Therefore, lycopene suppressed hypoxia-induced oxidative stress through HIF-1α-NOX4-ROS axis, thereby alleviating HPH. Our findings will provide a new research direction for clinical HPH therapies.

Effects of Lycopene Attenuating Injuries in Ischemia and Reperfusion

Tissue and organ ischemia can lead to cell trauma, tissue necrosis, irreversible damage, and death. While intended to reverse ischemia, reperfusion can further aggravate an ischemic injury (ischemia-reperfusion injury, I/R injury) through a range of pathologic processes. An I/R injury to one organ can also harm other organs, leading to systemic multiorgan failure. A type of carotenoid, lycopene, has been shown to treat and prevent many diseases (e.g., rheumatoid arthritis, cancer, diabetes, osteoporosis, male infertility, neurodegenerative diseases, and cardiovascular disease), making it a hot research topic in health care. Some recent researches have suggested that lycopene can evidently ameliorate ischemic and I/R injuries to many organs, but few clinical studies are available. Therefore, it is essential to review the effects of lycopene on ischemic and I/R injuries to different organs, which may help further research into its potential clinical applications.

Cardiovascular Disease and Possible Ways in Which Lycopene Acts as an Efficient Cardio-Protectant against Different Cardiovascular Risk Factors

Foods rich in antioxidants such as lycopene have a major role in maintaining cardiac health. Lycopene, 80% of which can be obtained by consuming a common vegetable such as tomato, can prevent the disturbances that contribute to cardiovascular disease (CVD). The present work begins with a brief introduction to CVD and lycopene and its various properties such as bioavailability, pharmacokinetics, etc. In this review, the potential cardio-protective effects of lycopene that reduce the progression of CVD and thrombotic complications are detailed. Further, the protective effects of lycopene including in vitro, in vivo and clinical trials conducted on lycopene for CVD protective effects are explained. Finally, the controversial aspect of lycopene as a protective agent against CVD and toxicity are also mentioned.

Lycopene: A Potent Antioxidant for the Amelioration of Type II Diabetes Mellitus

Nutrition is of utmost importance in chronic disease management and has often been described as the cornerstone of a variety of non-communicable diseases. In particular, type II diabetes mellitus (T2DM) represents a prevalent and global public health crisis. Lycopene, a bright red carotenoid hydrocarbon found in tomatoes and other red fruits and vegetables, has been extensively studied for its biological activities and treatment efficiency in diabetes care. Epidemiological investigations indicate that lycopene has potential antioxidant properties, is capable of scavenging reactive species, and alleviates oxidative stress in T2DM patients. This review aims to summarize the characteristics and mechanisms of action of lycopene as a potent antioxidant for T2DM. In addition, the evidence demonstrating the effects of lycopene on glycemic control and oxidative stress biomarkers in T2DM are also highlighted using animal and human studies as literature approach.

Scientific Evidence of the Beneficial Effects of Tomato Products on Cardiovascular Disease and Platelet Aggregation

Cardiovascular disease (CVD) includes a group of disorders of the heart and blood vessels that includes numerous problems, many of which are related to the process called atherosclerosis. The present work is aimed to analyze the most relevant studies examining the potentially beneficial effects of tomato products on both CVD prevention and antiplatelet aggregation as well as an European Food Safety Authority health claims evaluation on tomato and tomato products. To date, only one health claim has been approved for a concentrated extract of tomato soluble in water (WSTC) marketed under the patented name of Fruitflow® with two forms of presentation: WSTC I and II, with the following claim “helping to maintain normal platelet aggregation, which contributes to healthy blood flow.” Other studies also demonstrate similar beneficial effects for fresh tomatoes, tomato products and tomato pomace extracts.

Lycopene: A Natural Arsenal in the War against Oxidative Stress and Cardiovascular Diseases

Lycopene is a bioactive red pigment found in plants, especially in red fruits and vegetables, including tomato, pink guava, papaya, pink grapefruit, and watermelon. Several research reports have advocated its positive impact on human health and physiology. For humans, lycopene is an essential substance obtained from dietary sources to fulfil the body requirements. The production of reactive oxygen species (ROS) causing oxidative stress and downstream complications include one of the major health concerns worldwide. In recent years, oxidative stress and its counter strategies have attracted biomedical research in order to manage the emerging health issues. Lycopene has been reported to directly interact with ROS, which can help to prevent chronic diseases, including diabetes and neurodegenerative and cardiovascular diseases. In this context, the present review article was written to provide an accumulative account of protective and ameliorative effects of lycopene on coronary artery disease (CAD) and hypertension, which are the leading causes of death worldwide. Lycopene is a potent antioxidant that fights ROS and, subsequently, complications. It reduces blood pressure via inhibiting the angiotensin-converting enzyme and regulating nitrous oxide bioavailability. It plays an important role in lowering of LDL (low-density lipoproteins) and improving HDL (high-density lipoproteins) levels to minimize atherosclerosis, which protects the onset of coronary artery disease and hypertension. Various studies have advocated that lycopene exhibited a combating competence in the treatment of these diseases. Owing to all the antioxidant, anti-diabetic, and anti-hypertensive properties, lycopene provides a potential nutraceutical with a protective and curing ability against coronary artery disease and hypertension.

The novel role of the aquaporin water channel in lycopene preventing DEHP-induced renal ionic homeostasis disturbance in mice

Di-(2-ethylhexyl) phthalate (DEHP), an extensively used plasticizer, can cause environmental pollution and organ injury. Lycopene (LYC) is a natural carotene that has the potential to prevent chronic diseases. To reveal the effect of DEHP and/or LYC on the kidney, male mice were treated with LYC (5 mg/kg) and/or DEHP (500 mg/kg or 1000 mg/kg) by gavage for 28 days. The study indicated that DEHP caused glomerular atrophy, tubular expansion, disappearance of the mitochondrial membrane, and cristae rupture. DEHP exposure can increase the expression of aquaporin (AQP) subunits and the activity of Ca²⁺-Mg²⁺-ATPase and decrease the activity of Na⁺-K⁺-ATPase, which results in ion disorder. However, LYC can relieve kidney injury by regulating the activity of ATPase, the expression of ATPase subunits, and AQP subunit expression. The results indicated that AQP was a target for LYC in antagonizing the disturbance of DEHP-induced renal damage.

Lycopene and Chrysin through Mitigation of Neuroinflammation and Oxidative Stress Exerted Antidepressant Effects in Clonidine-Induced Depression-like Behavior in Rats

Depression is a severely debilitating psychiatric disorder that influences more than 15% of the population worldwide. It has been demonstrated that it is associated with a high risk of developing other diseases such as cardiovascular diseases, diabetes, stroke, epilepsy, and cancer. The current study examines the possibility of chrysin and lycopene having an antidepressant effect in a rat model of depression induced by clonidine, as well as the mechanisms underlying this effect, including the role of neuroinflammation and oxidative stress. Rats were allotted into seven groups. The rats in group 1 served as a control. Group 2 received lycopene only. Group 3 was provided chrysin only. Group 4 was administered clonidine and served as the model. Group 5 was offered lycopene and clonidine. Group 6 was administered chrysin and clonidine. Group 7 was given FLX and clonidine and represented the standard. The experiment lasted two weeks, during which behavioral, biochemical, histopathological, and immunohistochemical measurements were performed. Lycopene and chrysin were used to correct the concentrations of noradrenaline and serotonin hippocampal tissue concentrations. These findings were also improved by immunohistochemical analysis of GFAP, VEGF, caspase3, and histopathological examinations, in which pretreatment of rats with lycopene and chrysin reversed all clonidine-induced alterations. The current research demonstrates that lycopene and chrysin have an auspicious antidepressant effect against clonidine that provoked behavioral hopelessness in rats. Manipulating oxidative stress, inflammation, and apoptosis may partially represent the corrective mechanism for the neuroprotective actions against the depressive effect of clonidine.

The Potential of Exploiting Economical Solar Dryer in Food Preservation: Storability, Physicochemical Properties, and Antioxidant Capacity of Solar-Dried Tomato (Solanum lycopersicum) Fruits

This study investigated the effect of solar drying on storability and physiochemical and antioxidant capacities of dried tomatoes. Sliced fruit was dried at 45 ± 2 °C for 24 h under a solar tunnel dryer and stored at ambient temperature for 90 and 180 days. Solar drying treatments significantly (p < 0.05) reduced the bacterial and mold load, and eliminated Staphylococcus aureus, S. saprophyticus, and Escherichia coli in all samples. Solar drying treatment reduced the water activity of the dried tomato's to 0.31 that remained at the same level during storage period 180 days. Storage of dried tomato slices resulted in the decrease of both color and vitamin C content while it increased the total carotenoid, lycopene, phenolic compound content, and antioxidant activity. Furthermore, the principle component analysis (PCA) revealed that solar drying of tomato slices enhanced its physicochemical properties, antioxidant capacity particularly after storage for 90 and 180 days. Interestingly, the solar drying process enhanced tomato slices storage and physicochemical characteristics, that resulted in extending the shelf life by up to 6 months, indicating the great potential application of low-tech solar in food industry and could become an emerging effective post-harvest preservative method for seasonal perishable vegetable and fruit, particularly in developing countries.

Association between dietary carotenoid intakes and hypertension in adults: National Health and Nutrition Examination Survey 2007-2014

OBJECTIVE

Few epidemiological studies concentrated on dietary carotenoids and hypertension since new hypertension guideline released in 2017. Thus, this study was aimed to evaluate their association.

METHODS

Data from National Health and Nutrition Examination Survey (NHANES) 2007-2014 were used in this cross-sectional study. Dietary carotenoids data were obtained from 24-h dietary recall interviews. Hypertension was defined as SBP at least 130 mmHg or DBP at least 80 mmHg, taking antihypertensive medicine or self-report. Logistic regression models and restricted cubic spline models were applied to explore the associations between α-carotene, β-carotene, β-cryptoxanthin, lycopene, lutein with zeaxanthin, and total carotenoids from diet and supplements and hypertension. Total carotenoids showed significant reductive risk of hypertension at 100 μg/kg per day and over.

RESULTS

A total of 17 398 adults aged 20 years and over were identified. High dose of β-carotene, lycopene, lutein with zeaxanthin, and total carotenoids were significantly associated with decreased risk of hypertension in crude results. After multivariate-adjustment in model 2, the odds ratios (OR) with 95% confidence intervals (CI) of β-cryptoxanthin, lycopene, lutein with zeaxanthin and total carotenoids for hypertension were 0.79 (0.67-0.93), 0.85 (0.73-0.98), 0.69 (0.58-0.83), 0.73 (0.62-0.86) for the highest versus lowest quartile intakes, respectively. Dose-response analyses showed that all of the carotenoids were inversely associated with hypertension in a linear manner. Total carotenoids showed significant effect of lower risk of hypertension at 100 μg/kg per day.

CONCLUSION

Intakes of α-carotene, β-carotene, β-cryptoxanthin, lycopene, lutein with zeaxanthin, and total carotenoids were inversely associated with hypertension in US adults. The intake of total carotenoids was suggested at least 100 μg/kg per day for general adult population.

Unsalted tomato juice intake improves blood pressure and serum low-density lipoprotein cholesterol level in local Japanese residents at risk of cardiovascular disease

The aim of this study was to investigate the effects of unsalted tomato juice intake on cardiovascular risk markers in local Japanese residents. Four hundred and eighty-one local residents in Kuriyama, Japan, were enrolled in this study. Throughout the year of the study, they were provided with as much unsalted tomato juice as they wanted. Participants were screened for cardiovascular risk markers, such as blood pressure (BP), serum lipid profile, and glucose tolerance, before and after the study period. Of the study participants, 260 participated in a detailed study of their lifestyle factors. The average ages of the 184 male and 297 female participants were 56.3 ± 13.3 (mean ± SD) and 58.4 ± 11.7 years, respectively. BP in 94 participants with untreated prehypertension or hypertension was significantly lowered (systolic BP, 141.2 ± 12.1-137.0 ± 16.3 mmHg, p = 0.003; diastolic BP, 83.3 ± 10.1-80.9 ± 11.1 mmHg, p = 0.012, paired t test). Further, the serum low-density lipoprotein cholesterol (LDL-C) level in 125 participants with untreated dyslipidemia significantly decreased (155.0 ± 23.2-149.9 ± 25.0 mg/dl, p = 0.005, paired t test). These beneficial effects were not different between sexes and among the different age groups. No significant difference in lifestyle was found before and after the study. Unsalted tomato juice intake improved systolic and diastolic BP and serum LDL-C level in local Japanese residents at risk of cardiovascular conditions.

Higher dietary and serum carotenoid levels are associated with lower carotid intima-media thickness in middle-aged and elderly people

Several studies have suggested that higher carotenoid levels may be beneficial for atherosclerosis patients, but few studies have examined this relationship in the Chinese population. This cross-sectional study examined the association between the levels of carotenoids in diet and serum and carotid intima-media thickness (IMT) in Chinese adults aged 50-75 years in Guangzhou, China. Dietary intake was assessed using a FFQ. HPLC was used to assay the serum concentrations of α-carotene, β-carotene, lutein+zeaxanthin, β-cryptoxanthin and lycopene. The IMT at the common carotid artery (CCA) and bifurcation of the carotid artery was measured by B-mode ultrasound. A total of 3707 and 2947 participants were included in the analyses of dietary and serum carotenoids. After adjustment for demographic, socio-economic and lifestyle factors, all the serum carotenoids levels except lycopene were found to be inversely associated with the IMT at the CCA and bifurcation (P trend<0·001 to 0·013) in both men and women. The absolute mean differences in the IMT between the subjects in the extreme quartiles of serum carotenoid levels were 0·034 mm (α-carotene), 0·037 mm (β-carotene), 0·032 mm (lutein+zeaxanthin), 0·030 mm (β-cryptoxanthin), 0·015 mm (lycopene) and 0·035 mm (total carotenoids) at the CCA; the corresponding values were 0·025, 0·053 0·043, 0·050, 0·011 and 0·042 mm at the bifurcation. The favourable associations were also observed between dietary carotenoids (except lycopene) and the CCA IMT. In conclusion, elevated carotenoid levels in diet and serum are associated with lower carotid IMT values (particular at the CCA) in Chinese adults.

Dietary Composition and Cardiovascular Risk: A Mediator or a Bystander?

The role of nutrition in the pathogenesis of cardiovascular disease has long been debated. The established notion of the deleterious effects of fat is recently under question, with numerous studies demonstrating the benefits of low-carbohydrate, high-fat diets in terms of obesity, diabetes, dyslipidemia, and metabolic derangement. Monounsaturated and polyunsaturated fatty acids, especially n-3 PUFAs (polyunsaturated fatty acids), are the types of fat that favor metabolic markers and are key components of the Mediterranean Diet, which is considered an ideal dietary pattern with great cardioprotective effects. Except for macronutrients, however, micronutrients like polyphenols, carotenoids, and vitamins act on molecular pathways that affect oxidative stress, endothelial function, and lipid and glucose homeostasis. In relation to these metabolic markers, the human gut microbiome is constantly revealed, with its composition being altered by even small dietary changes and different microbial populations being associated with adverse cardiovascular outcomes, thus becoming the target for potential new treatment interventions. This review aims to present the most recent data concerning different dietary patterns at both the macro- and micronutrient level and their association with atherosclerosis, obesity, and other risk factors for cardiovascular disease.

Antioxidant and neuroprotective effects of lycopene and insulin in the hippocampus of streptozotocin-induced diabetic rats

In the present study the antioxidant and neuroprotective effects of insulin and lycopene on passive avoidance memory, total antioxidant capacity (TAC), malondialdehyde activity (MDA) and prevention of apoptosis in the hippocampus streptozotocin-induced diabetic rats were examined. The rats were randomly divided to six experimental groups (n=8 per group): Non-diabetic (controls); diabetic; diabetic treated with lycopene; diabetic treated with insulin; diabetic treated with lycopene and insulin; and normal treated with lycopene. Intraperitoneal injection of single dose (60 mg/kg) streptozotocin (STZ) was used to induce the diabetes rat model. The shuttle box test was used for learning and memory assessment. Rats were then sacrificed and hippocampi tissue isolated from the two hemispheres to determine TAC and MDA. Apoptosis rate was also evaluated by terminal deoxynucleotidyl transferase dUTP nick-end labeling and acridine orange staining assays. The results indicated that lycopene and insulin, solely or in combination, prevented hippocampal neuronal cell death and improved learning and cognition by increasing TAC and decreasing MDA. Collectively, the findings presented herein suggest that insulin and lycopene co-treatment has neuroprotective effect, and ameliorates STZ-induced learning and memory impairment and apoptotic cell death in the hippocampal regions of diabetic rats.

Association of serum lutein and zeaxanthin with quantitative measures of retinal vascular parameters

To evaluate the association between serum carotenoids and quantitative measures of retinal vasculature in elderly Singapore Chinese subjects. The following details were collected in 128 healthy subjects: sociodemographics, lifestyle information, medical and drug history, and anthropometric measurements. Serum concentrations of carotenoids were estimated in fasting venous blood using high performance liquid chromatography. Retinal vascular parameters were quantitatively measured from retinal photographs using a computer-assisted program (Singapore I Vessel Assessment). The mean age of the population was 54.1 years (range 40 to 81 years). In multiple linear regression analysis, per SD decrease in retinal arteriolar caliber [β = 0.045 (0.003 to 0.086), p = 0.036], per SD increase in retinal venular caliber [β = -0.045 (-0.086 to -0.003), p = 0.036] and per SD increase in arteriolar branching angle [β = -0.039 (-0.072 to -0.006), p = 0.021] were associated with decreased serum lutein. Per SD increase in retinal venular tortuosity [β = -0.0075 (-0.0145 to -0.0004), p = 0.039] and per SD increase in arteriolar branching angle (β = -0.0073 [-0.0142 to -0.0059], p = 0.041) were associated with decreased serum zeaxanthin. None of the other carotenoids demonstrated meaningful relationship with quantitative measures of retinal vasculature. Lower levels of lutein and zeaxanthin demonstrated significant relationship with adverse quantitative measures of retinal vasculature in elderly healthy subjects.

Lycopene and Vascular Health

Lycopene is a lipophilic, unsaturated carotenoid, found in red-colored fruits and vegetables, including tomatoes, watermelon, papaya, red grapefruits, and guava. The present work provides an up to date overview of mechanisms linking lycopene in the human diet and vascular changes, considering epidemiological data, clinical studies, and experimental data. Lycopene may improve vascular function and contributes to the primary and secondary prevention of cardiovascular disorders. The main activity profile of lycopene includes antiatherosclerotic, antioxidant, anti-inflammatory, antihypertensive, antiplatelet, anti-apoptotic, and protective endothelial effects, the ability to improve the metabolic profile, and reduce arterial stiffness. In this context, lycopene has been shown in numerous studies to exert a favorable effect in patients with subclinical atherosclerosis, metabolic syndrome, hypertension, peripheral vascular disease, stroke and several other cardiovascular disorders, although the obtained results are sometimes inconsistent, which warrants further studies focusing on its bioactivity.

The plant growth-promoting bacterium Kosakonia radicincitans improves fruit yield and quality of Solanum lycopersicum

BACKGROUND

Production and the quality of tomato fruits have a strong economic relevance. Microorganisms such as the plant growth-promoting bacterium (PGPB) Kosakonia radicincitans (DSM 16656) have been demonstrated to improve shoot and root growth of young tomato plants, but data on yield increase and fruit quality by K. radicincitans are lacking.

RESULTS

This study investigated how K. radicincitans affects tomato fruits. After inoculation of tomato seeds with K. radicincitans or a sodium chloride buffer control solution, stalk length, first flowering and the amount of ripened fruits produced by inoculated and non-inoculated plants were monitored over a period of 21 weeks. Inoculation of tomato seeds with K. radicincitans accelerated flowering and ripening of tomato fruits. Sugars, acidity, amino acids, volatile organic compounds and carotenoids in the fruits were also analyzed.

CONCLUSION

It was found that the PGPB K. radicincitans affected the amino acid, sugar and volatile composition of ripened fruits, contributing to a more pleasant-tasting fruit without forfeiting selected quality indicators. © 2017 Society of Chemical Industry.

Lycopene Inhibits Propagation of Chlamydia Infection

Chlamydiaceae is a family of obligate intracellular pathogenic bacteria with similar developmental cycles and cell biology responsible for a wide range of diseases in different hosts including genital and eye inflammatory diseases, arthritis, and inflammatory diseases of the respiratory and cardiovascular systems. In the present paper, we report that lycopene, one of the main dietary carotenoids, which is present in tomato and some other fruits, has a strong inhibitory effect on C. trachomatis and C. pneumoniae infections in alveolar macrophages. This finding was documented by both immunofluorescence analysis and electron microscopy. It was noted that lycopene treatment inhibited intracellular phase of the chlamydial developmental cycle and resulted in a significant loss of infectious progeny. The antichlamydial effect of lycopene was also confirmed in a clinical setting. There was a significant reduction of IgG antibodies against C. pneumoniae in the serum of volunteers treated for a month with oral ingestion of 7 mg of lycopene. Additional studies are needed to further explore the antichlamydial activity of lycopene and its possible effect on C. pneumoniae in relation to antichlamydial activity of lycopene to mechanisms of atherosclerosis.

Host-related factors explaining interindividual variability of carotenoid bioavailability and tissue concentrations in humans

Carotenoid dietary intake and their endogenous levels have been associated with a decreased risk of several chronic diseases. There are indications that carotenoid bioavailability depends, in addition to the food matrix, on host factors. These include diseases (e.g. colitis), life-style habits (e.g. smoking), gender and age, as well as genetic variations including single nucleotide polymorphisms that govern carotenoid metabolism. These are expected to explain interindividual differences that contribute to carotenoid uptake, distribution, metabolism and excretion, and therefore possibly also their association with disease risk. For instance, digestion enzymes fostering micellization (PNLIP, CES), expression of uptake/efflux transporters (SR-BI, CD36, NPC1L1), cleavage enzymes (BCO1/2), intracellular transporters (FABP2), secretion into chylomicrons (APOB, MTTP), carotenoid metabolism in the blood and liver (LPL, APO C/E, LDLR), and distribution to target tissues such as adipose tissue or macula (GSTP1, StARD3) depend on the activity of these proteins. In addition, human microbiota, e.g. via altering bile-acid concentrations, may play a role in carotenoid bioavailability. In order to comprehend individual, variable responses to these compounds, an improved knowledge on intra-/interindividual factors determining carotenoid bioavailability, including tissue distribution, is required. Here, we highlight the current knowledge on factors that may explain such intra-/interindividual differences.

Association between Micronutrients Intake/Status and Carotid Intima Media Thickness: A Systematic Review

BACKGROUND

Carotid intima media thickness (IMT) is a noninvasive marker of the extent and severity of subclinical atherosclerosis. Micronutrient intake may affect atherosclerosis and play a major role in the development of cardiovascular diseases (CVDs).

OBJECTIVE

The primary aim of this review was to synthesize the evidence regarding the association between carotid IMT and selected micronutrients.

METHOD

The authors searched PubMed, Cochrane, and EMBASE databases from inception to June 2016 for selected micronutrients, CVD, carotid IMT, and antioxidants. Thirty-five original studies met the inclusion criteria and were reviewed following preferred reporting items for systematic review and meta-analysis guidelines.

RESULTS

Although not all studies found consistent results, the weight of the evidence suggests that high intakes and/or circulatory levels of magnesium, as well as vitamin D and the vitamin B group, may be associated with lower carotid IMT or reduced progression of carotid IMT. The majority of studies did not find any significant association between vitamin E and C and carotid IMT. Less evidence was available for associations of retinol, zinc, and iron with carotid IMT.

CONCLUSIONS

In general, the current evidence concerning micronutrient intake and carotid IMT is largely inconclusive. Pragmatic clinical trials are required to determine whether dietary or supplemental intake of specific micronutrients alters carotid IMT, which is a surrogate measure of cardiovascular risk.

Tomato (Solanum lycopersicum) Carotenoids and Lycopenes Chemistry; Metabolism, Absorption, Nutrition, and Allied Health Claims--A Comprehensive Review

Tomato (Solanum lycopersicum) is one of the most essential herbaceous plants that have been probed against various life sight related disorders owing to array of phytochemicals. It is important source of vitamin C, potassium, folic acid, and carotenoids, such as lycopene. Carotenoids are the pigments synthesized during fruit ripening and responsible for the final red color of the tomato. Consumption of tomato and tomato-based products contribute to the absorption of carotenoids and lycopenes in human serum. Lycopene is chemically acyclic carotene with 11 conjugated double bonds, normally in transconfiguration while isomerization occur in blood plasma for its better absorption. It has ability for adenosine deaminase inhibition that plays important role in the regression of tumor. Tomato also contain other active compounds, namely, neoxanthin, lutein, α-cryptoxanthin, α-carotene, β-carotene, cyclolycopene, and β-carotene 5, 6-epoxide. These components provide synergistic effect against various threats but still need further attention of the researchers. Both in vitro and in vivo studies have elucidated the potential of tomato against variety of metabolic syndromes. Latest research highlights the relationship between consuming tomato and its products with reduced risk of various maladies like obesity, hyperglycemic and hypercholesterolemic attributes, cardiovascular disorders, and cancer insurgences. Moreover, tomato and its bioactive components hold potential to become effective modules in diet-based regimens; however, integrated research and meta-analysis are still required to enhance meticulousness.

Lycopene dietary intervention: a pilot study in patients with heart failure

BACKGROUND/OBJECTIVES

Heart failure (HF) is a condition of chronic exacerbations and injury resulting from an intricate relationship between biochemical and biological mechanisms. Inflammation can be a significant contributor in the pathophysiology of HF. Antioxidants may slow the progression of HF because of their ability to inhibit damaging inflammatory processes. The purpose of this study was to test a dietary intervention in patients with HF to assess the impact of lycopene on biomarkers of inflammation.

SUBJECTS/METHODS

Forty participants with HF were randomly assigned to 1 of 2 groups: lycopene intervention and usual care. The lycopene intervention group received 29.4 mg of lycopene intake per day by drinking an 11.5 oz serving of V8 100% vegetable juice for 30 days. We obtained serum lycopene, uric acid, C-reactive protein (CRP), and b-type natriuretic peptide to determine the impact of the intervention.

RESULTS

Plasma lycopene levels increased in the intervention group compared with the usual care group (0.51 μmol/L to 0.76 μmol/L, P = .002; 0.56 μmol/L to 0.58 μmol/L). C-reactive protein levels decreased significantly in the intervention group in women and but not in men (P = .04). The preintervention CRP level for women was 5.9 ± 3.7 mg/dL and for men was 2.2 ± 2.1 mg/dL. The postintervention CRP level for women was 4.5 ± 3.6 mg/dL and for men was 2.4 ± 2.1 mg/dL.

CONCLUSIONS

These findings suggest that the antioxidants in a 30-day intervention of V8 juice affect CRP levels in a sample of female patients with HF.

The effects of lutein on cardiometabolic health across the life course: a systematic review and meta-analysis

BACKGROUND

The antioxidant lutein is suggested as being beneficial to cardiometabolic health because of its protective effect against oxidative stress, but evidence has not systematically been evaluated.

OBJECTIVE

We aimed to evaluate systematically the effects of lutein (intake or concentrations) on cardiometabolic outcomes in different life stages.

DESIGN

This is a systematic review with meta-analysis of literature published in MEDLINE, Embase, Cochrane Central, Web of Science, PubMed, and Google Scholar up to August 2014. Included were trials and cohort, case-control, and cross-sectional studies in which the association between lutein concentrations, dietary intake, or supplements and cardiometabolic outcomes was reported. Two independent investigators reviewed the articles.

RESULTS

Seventy-one relevant articles were identified that included a total of 387,569 participants. Only 1 article investigated the effects of lutein during pregnancy, and 3 studied lutein in children. Furthermore, 31 longitudinal, 33 cross-sectional, and 3 intervention studies were conducted in adults. Meta-analysis showed a lower risk of coronary heart disease (pooled RR: 0.88; 95% CI: 0.80, 0.98) and stroke (pooled RR: 0.82; 95% CI: 0.72, 0.93) for the highest compared with the lowest tertile of lutein blood concentration or intake. There was no significant association with type 2 diabetes mellitus (pooled RR: 0.97; 95% CI: 0.77, 1.22), but higher lutein was associated with a lower risk of metabolic syndrome (pooled RR: 0.75; 95% CI: 0.60, 0.92) for the highest compared with the lowest tertile. The literature on risk factors for cardiometabolic diseases showed that lutein might be beneficial for atherosclerosis and inflammatory markers, but there were inconsistent associations with blood pressure, adiposity, insulin resistance, and blood lipids.

CONCLUSIONS

Our findings suggest that higher dietary intake and higher blood concentrations of lutein are generally associated with better cardiometabolic health. However, evidence mainly comes from observational studies in adults, whereas large-scale intervention studies and studies of lutein during pregnancy and childhood are scarce.

A review of the effect of diet on cardiovascular calcification

Cardiovascular (CV) calcification is known as sub-clinical atherosclerosis and is recognised as a predictor of CV events and mortality. As yet there is no treatment for CV calcification and conventional CV risk factors are not consistently correlated, leaving clinicians uncertain as to optimum management for these patients. For this reason, a review of studies investigating diet and serum levels of macro- and micronutrients was carried out. Although there were few human studies of macronutrients, nevertheless transfats and simple sugars should be avoided, while long chain ω-3 fats from oily fish may be protective. Among the micronutrients, an intake of 800 μg/day calcium was beneficial in those without renal disease or hyperparathyroidism, while inorganic phosphorus from food preservatives and colas may induce calcification. A high intake of magnesium (≥380 mg/day) and phylloquinone (500 μg/day) proved protective, as did a serum 25(OH)D concentration of ≥75 nmol/L. Although oxidative damage appears to be a cause of CV calcification, the antioxidant vitamins proved to be largely ineffective, while supplementation of α-tocopherol may induce calcification. Nevertheless other antioxidant compounds (epigallocatechin gallate from green tea and resveratrol from red wine) were protective. Finally, a homocysteine concentration >12 µmol/L was predictive of CV calcification, although a plasma folate concentration of >39.4 nmol/L could both lower homocysteine and protect against calcification. In terms of a dietary programme, these recommendations indicate avoiding sugar and the transfats and preservatives found in processed foods and drinks and adopting a diet high in oily fish and vegetables. The micronutrients magnesium and vitamin K may be worthy of further investigation as a treatment option for CV calcification.

A Review of the Structure, Biosynthesis, Absorption of Carotenoids-Analysis and Properties of their Common Natural Extracts

Carotenoids are a class of natural pigments familiar to all through the orange-red colours of popular foods like oranges, tomatoes and carrots and the yellow colour of many flowers. They have been studied for a number of years because of their diverse roles in photobiology, photochemistry and photo medicine. Carotenoids are also added as colorants to many manufactured foods, drinks, and animal feeds, either in the forms of natural extracts (e.g annatto, paprika or marigold extracts) or as pure compounds manufactured by chemical synthesis. Carotenoids are often described as provitamins A, as this particular vitamin is a product of carotenoid metabolism. The distribution of carotenoids among the different plant groups shows no obvious pattern. b-Carotene is the most abundant in leafy vegetables, though the colour is masked by its co-existence with chlorophyll, and this carotenoid has the highest vitamin A activity. Zeaxanthin, a-carotene and antheraxanthin are also present in small amounts. In the tomato, lycopene is the major carotenoid, while fruits contain varying proportions of cryptoxanthin, lutein and antheraxanthin. In this review paper the natural occurrence of carotenoids (with focus on certain natural extracts) is described along with its structure and physicochemical properties. The biosynthesis - industrial synthesis and absorption of carotenoids is also discussed. Finally, a brief overview of analysis and properties of commonly available natural carotenoid extracts (annato, paprika, xanthophylls, lycopene) are also reported.

Carotenoids: potential allies of cardiovascular health?

Carotenoids are a class of natural, fat-soluble pigments found principally in plants. They have potential antioxidant biological properties because of their chemical structure and interaction with biological membranes. Epidemiologic studies supported the hypothesis that antioxidants could be used as an inexpensive means of both primary and secondary cardiovascular disease (CVD) prevention. In fact, the oxidation of low-density lipoproteins (LDL) in the vessels plays a key role in the development of atherosclerotic lesions. The resistance of LDL to oxidation is increased by high dietary antioxidant intake, so that carotenoids, as part of food patterns such as the Mediterranean diet, may have beneficial effects on cardiovascular health too. Further properties of carotenoids leading to a potential reduction of cardiovascular risk are represented by lowering of blood pressure, reduction of pro-inflammatory cytokines and markers of inflammation (such as C-reactive protein), and improvement of insulin sensitivity in muscle, liver, and adipose tissues. In addition, recent nutrigenomics studies have focused on the exceptional ability of carotenoids in modulating the expression of specific genes involved in cell metabolism. The aim of this review is to focus attention to this effect of some carotenoids to prevent CVD.

Whole food versus supplement: comparing the clinical evidence of tomato intake and lycopene supplementation on cardiovascular risk factors

Cardiovascular disease (CVD) is a major contributor to morbidity and mortality in the United States and worldwide. A link between diet and CVD is well established, with dietary modification a foundational component of CVD prevention and management. With the discovery of bioactive components beyond the essential nutrients of foods, a new era of nutritional, medical, botanical, physiologic, and analytical sciences has unfolded. The ability to identify, isolate, purify, and deliver single components has expanded the dietary supplement business and health opportunity for consumers. Lycopene is an example of a food component that has attracted attention from scientists as well as food, agriculture, and dietary supplement industries. A major question, however, is whether delivering lycopene through a supplement source is as effective as or more effective than consuming lycopene through whole food sources, specifically the tomato, which is the richest source of lycopene in the Western diet. In this review, we examined clinical trials comparing the efficacy of lycopene supplements with tomato products on intermediate CVD risk factors including oxidative stress, inflammation, endothelial function, blood pressure, and lipid metabolism. Overall, the present review highlights the need for more targeted research; however, at present, the available clinical research supports consuming tomato-based foods as a first-line approach to cardiovascular health. With the exception of blood pressure management where lycopene supplementation was favored, tomato intake provided more favorable results on cardiovascular risk endpoints than did lycopene supplementation. Indeed, future research that is well designed, clinically focused, mechanistically revealing, and relevant to human intake will undoubtedly add to the growing body of knowledge unveiling the promise of tomatoes and/or lycopene supplementation as an integral component of a heart-healthy diet.

Dietary intake of carotenoids and their antioxidant and anti-inflammatory effects in cardiovascular care

Cardiovascular disease related to atherosclerosis represents nowadays the largest cause of morbidity and mortality in developed countries. Due to inflammatory nature of atherosclerosis, several studies had been conducted in order to search for substances with anti-inflammatory activity on arterial walls, able to exert beneficial roles on health. Researches investigated the role of dietary carotenoids supplementation on cardiovascular disease, due to their free radicals scavenger properties and their skills in improving low-density lipoprotein cholesterol resistance to oxidation. Nevertheless, literature data are conflicting: although some studies found a positive relationship between carotenoids supplementation and cardiovascular risk reduction, others did not find any positive effects or even prooxidant actions. This paper aimed at defining the role of carotenoids supplementation on cardiovascular risk profile by reviewing literature data, paying attention to those carotenoids more present in our diet (β-carotene, α-carotene, β-cryptoxanthin, lycopene, lutein, zeaxanthin, and astaxanthin).

Influence of acidification, pasteurization, centrifugation and storage time and temperature on watermelon juice quality

BACKGROUND

Watermelon juice has gained increasing popularity among consumers as a rich natural source of functional compounds such as lycopene and citrulline. However, the final quality of the juice depends significantly on its acidification, pasteurization, centrifugation and storage time and temperature. In this study, these characteristics were assessed in watermelon juice pasteurized at 87.7 °C for 20 s and stored for up to 30 days at 4 or 8 °C.

RESULTS

The acidifier citric acid provided an adequate sensory quality, similar to natural watermelon juice. Centrifugation and pasteurization significantly reduced the red color, bioactive compounds (lycopene, antioxidant capacity and total polyphenols) and sensory quality of the juice, particularly when the storage time was extended and a temperature of 8 °C was used (P ≤ 0.05). All treated juices were microbiologically safe for up to 30 days when stored at 4 or 8 °C. In terms of sensory acceptability, only non-centrifuged juices stored for up to 20 days at 4 °C remained above the commercial limit.

CONCLUSION

The present results suggest that using a non-centrifugation process and a storage temperature of 4 °C yields a watermelon juice that better retains its sensory and functional qualities.

Effects of lutein and lycopene on carotid intima-media thickness in Chinese subjects with subclinical atherosclerosis: a randomised, double-blind, placebo-controlled trial

The aim of the present study was to evaluate the effects of lutein and lycopene supplementation on carotid artery intima-media thickness (CAIMT) in subjects with subclinical atherosclerosis. A total of 144 subjects aged 45-68 years were recruited from local communities. All the subjects were randomly assigned to receive 20 mg lutein/d (n 48), 20 mg lutein/d+20 mg lycopene/d (n 48) or placebo (n 48) for 12 months. CAIMT was measured using Doppler ultrasonography at baseline and after 12 months, and serum lutein and lycopene concentrations were determined using HPLC. Serum lutein concentrations increased significantly from 0·34 to 1·96 μmol/l in the lutein group (P< 0·001) and from 0·35 to 1·66 μmol/l in the combination group (P< 0·001). Similarly, serum lycopene concentrations increased significantly from 0·18 to 0·71 μmol/l in the combination group at month 12 (P< 0·001), whereas no significant change was observed in the placebo group. The mean values of CAIMT decreased significantly by 0·035 mm (P= 0·042) and 0·073 mm (P< 0·001) in the lutein and combination groups at month 12, respectively. The change in CAIMT was inversely associated with the increase in serum lutein concentrations (P< 0·05) in both the active treatment groups and with that in serum lycopene concentrations (β = - 0·342, P= 0·031) in the combination group. Lutein and lycopene supplementation significantly increased the serum concentrations of lutein and lycopene with a decrease in CAIMT being associated with both concentrations. In addition, the combination of lutein and lycopene supplementation was more effective than lutein alone for protection against the development of CAIMT in Chinese subjects with subclinical atherosclerosis, and further studies are needed to confirm whether synergistic effects of lutein and lycopene exist.

Lycopene protects against hypoxia/reoxygenation-induced apoptosis by preventing mitochondrial dysfunction in primary neonatal mouse cardiomyocytes

BACKGROUND

Hypoxia/reoxygenation(H/R)-induced apoptosis of cardiomyocytes plays an important role in myocardial injury. Lycopene is a potent antioxidant carotenoid that has been shown to have protective properties on cardiovascular system. The aim of the present study is to investigate the potential for lycopene to protect the cardiomyocytes exposed to H/R. Moreover, the effect on mitochondrial function upon lycopene exposure was assessed.

METHODS AND FINDINGS

Primary cardiomyocytes were isolated from neonatal mouse and established an in vitro model of H/R which resembles ischemia/reperfusion in vivo. The pretreatment of cardiomyocytes with 5 µM lycopene significantly reduced the extent of apoptosis detected by TUNEL assays. To further study the mechanism underlying the benefits of lycopene, interactions between lycopene and the process of mitochondria-mediated apoptosis were examined. Lycopene pretreatment of cardiomyocytes suppressed the activation of the mitochondrial permeability transition pore (mPTP) by reducing the intracellular reactive oxygen species (ROS) levels and inhibiting the increase of malondialdehyde (MDA) levels caused by H/R. Moreover, the loss of mitochondrial membrane potential, a decline in cellular ATP levels, a reduction in the amount of cytochrome c translocated to the cytoplasm and caspase-3 activation were observed in lycopene-treated cultures.

CONCLUSION

The present results suggested that lycopene possesses great pharmacological potential in protecting against H/R-induced apoptosis. Importantly, the protective effects of lycopene may be attributed to its roles in improving mitochondrial function in H/R-treated cardiomyocytes.

Lycopene inhibits lymphocyte proliferation through mechanisms dependent on early cell activation

SCOPE

Epidemiological evidence suggests that lycopene is potentially cardio-protective. Recruitment and activation of T cells in the arterial wall is a critical process during atherogenesis, but the effects of lycopene on T-cell response remain to be elucidated. We aimed to determine whether lycopene could modulate T-cell function and activity.

METHODS AND RESULTS

Peripheral blood mononuclear cells from 16 healthy adults were cultured in the presence of lycopene-enriched liposomes (0-2.9 μg lycopene/mL) with or without mitogens. Cell cycle as well as the expression of CD69 (marker of early cell activation), CD25 (IL-2 receptor), and CD11a (late activation marker) were measured in T cells, T-helper cells, and T-cytotoxic cells by flow cytometry. IL-2 secretion and cell proliferation were determined by ELISA and [³H]-thymidine incorporation, respectively. Lycopene significantly inhibited lymphocyte proliferation (up to 40%) in activated cells. Lycopene also significantly inhibited CD69 expression (by up to 12%) as well as IL-2 secretion (by up to 29%). However, CD25 and CD11a expression as well as the cell-cycle profile were unaffected by lycopene.

CONCLUSION

Lycopene influences lymphocyte proliferation through its effects on processes involved in early cellular activation, providing one possible mechanism to explain the beneficial effects of tomato-rich diets against cardiovascular disease.

Higher dietary lycopene intake is associated with longer cardiac event-free survival in patients with heart failure

BACKGROUND

The antioxidant lycopene may be beneficial for patients with heart failure (HF). Processed tomato products are a major source of lycopene, although they are also high in sodium. Increased sodium intake may counter the positive antioxidant effect of lycopene.

METHODS

This was a prospective study of 212 patients with HF. Dietary intake of lycopene and sodium was obtained from weighted 4-day food diaries. Patients were grouped by the median split of lycopene of 2471 µg/day and stratified by daily sodium levels above and below 3 g/day. Patients were followed for 1 year to collect survival and hospitalization data. Cox proportional hazards modeling was used to compare cardiac event-free survival between lycopene groups within each stratum of sodium intake.

RESULTS

Higher lycopene intake was associated with longer cardiac event-free survival compared with lower lycopene intake (p = 0.003). The worst cardiac event-free survival was observed in the low lycopene intake group regardless of sodium intake (> 3 g/day HR = 3.01; p = 0.027 and ≤ 3 g/day HR= 3.34; p = 0.023).

CONCLUSION

These findings suggest that increased lycopene intake has the potential to improve cardiac event-free survival in patients with HF independent of sodium intake.

Serum carotenoids in relation to risk factors for development of atherosclerosis

OBJECTIVE

To explore associations between serum carotenoids and risk factors for development of atherosclerosis.

DESIGN AND METHODS

We studied 40 early atherosclerosis patients without clinical cardiovascular events and comparable healthy controls aged 45-68 years. Intima-media thickness (IMT) and arterial stiffness were simultaneously measured by carotid ultrasonography, and serum carotenoids and cytokines were determined by high-pressure liquid chromatograph (HPLC) and ELISA kits respectively. We evaluated the associations between serum carotenoids, early atherosclerosis and serum cytokines.

RESULTS

Serum concentrations of lutein and zeaxanthin in early atherosclerosis patients were significantly lower than those of control subjects. PCA logistic analysis found that serum carotenoids were associated with decreased risk of atherosclerosis. In contrast, blood pressure, body mass index and serum triglyceride were positively related to the risk of atherosclerosis. Ridge regression analysis revealed that serum carotenoids were associated with inflammatory cytokines and apoE. More specifically, serum lutein was inversely associated with IL-6 (P<0.001) and positively associated IFN-γ (P=0.002). In contrast, zeaxanthin had a significant negative association with VCAM-1 (P=0.001) and apoE (P=0.022) .Lycopene was inversely associated with VCAM-1(P=0.011) and LDL (P=0.046).

CONCLUSIONS

The results suggested that early atherosclerosis patients had lower serum concentrations of lutein and zeaxanthin than healthy subjects. Serum carotenoids were associated with reduced risk of atherosclerosis. The associations between serum carotenoids and inflammatory cytokines may help to explain the possible protective effects of carotenoids on atherosclerosis.

How can diet influence the risk of stroke?

Cerebrovascular diseases are the second cause of mortality in the world, and hypertension is considered a main risk factor for occurrence of stroke. The mechanisms responsible for the increased stroke risk remain unclear. However, dietary interventions have been applied in the management and treatment of their risk factors, which include increased blood pressure levels, obesity, diabetes, and dyslipidemia. Further studies should be conducted to assess the effects of carotenoids, flavonoids, n-3 polyunsaturated fats, and lower salt and high glycemic index intake in risk of stroke.

Effect of a tomato-rich diet on markers of cardiovascular disease risk in moderately overweight, disease-free, middle-aged adults: a randomized controlled trial

BACKGROUND

Cardiovascular disease (CVD) is a major cause of mortality in the United Kingdom. Epidemiologic studies suggest that consumption of tomato-based foods may lower CVD risk. Such potential benefits have been ascribed in part to high concentrations of lycopene in the tomatoes. However, these findings have not yet been validated by comprehensive intervention trials.

OBJECTIVE

The aim of this study was to conduct a single-blind, randomized controlled intervention trial with healthy middle-aged volunteers to assess whether the consumption of tomato-based foods affects recognized biomarkers of CVD risk.

DESIGN

After a 4-wk run-in period with a low-tomato diet, 225 volunteers (94 men and 131 women) aged 40-65 y were randomly assigned into 1 of 3 dietary intervention groups and asked to consume a control diet (low in tomato-based foods), a high-tomato-based diet, or a control diet supplemented with lycopene capsules (10 mg/d) for 12 wk. Blood samples were collected at baseline, at 6 wk, and after the intervention and were analyzed for carotenoid and lipid profiles and inflammatory markers. Blood pressure, weight, and arterial stiffness were also measured. Dietary intake was also determined during the intervention.

RESULTS

None of the systemic markers (inflammatory markers, markers of insulin resistance and sensitivity) changed significantly after the dietary intervention. Moreover, lipid concentrations and arterial stiffness were also unaffected by the interventions.

CONCLUSION

These data indicate that a relatively high daily consumption of tomato-based products (equivalent to 32-50 mg lycopene/d) or lycopene supplements (10 mg/d) is ineffective at reducing conventional CVD risk markers in moderately overweight, healthy, middle-aged individuals. This trial was registered at isrctn.org as ISRCTN34203810.