Effects of lycopene intake on HDL-cholesterol and triglyceride levels: A systematic review with meta-analysis

Lycopene: A Potent Antioxidant with Multiple Health Benefits

Lycopene is a naturally occurring carotenoid predominantly found in tomatoes and tomato-based products. Like other phytochemicals, it exhibits health beneficial biological activities that can be exploited when it is used as a dietary supplement. In vitro and in vivo, lycopene has been demonstrated to mitigate oxidative stress-induced metabolic dysfunctions and diseases including inflammation, obesity, and diabetes mellitus. Lycopene has been shown to alleviate metabolic diseases that affect the bone, eye, kidney, liver, lungs, heart, and nervous system. This review presents the state of the art regarding lycopene's health benefits and its potential applications in health system delivery. Furthermore, lycopene's protective effects against toxins, safety in its use, and possible toxicity are explored.

Lycopene in Combination with Insulin Triggers Antioxidant Defenses and Increases the Expression of Components That Detoxify Advanced Glycation Products in Kidneys of Diabetic Rats

BACKGROUND

Biochemical events provoked by oxidative stress and advanced glycation may be inhibited by combining natural bioactives with classic therapeutic agents, which arise as strategies to mitigate diabetic complications. The aim of this study was to investigate whether lycopene combined with a reduced insulin dose is able to control glycemia and to oppose glycoxidative stress in kidneys of diabetic rats.

METHODS

Streptozotocin-induced diabetic rats were treated with 45 mg/kg lycopene + 1 U/day insulin for 30 days. The study assessed glycemia, insulin sensitivity, lipid profile and paraoxonase 1 (PON-1) activity in plasma. Superoxide dismutase (SOD) and catalase (CAT) activities and the protein levels of advanced glycation end-product receptor 1 (AGE-R1) and glyoxalase-1 (GLO-1) in the kidneys were also investigated.

RESULTS

An effective glycemic control was achieved with lycopene plus insulin, which may be attributed to improvements in insulin sensitivity. The combined therapy decreased the dyslipidemia and increased the PON-1 activity. In the kidneys, lycopene plus insulin increased the activities of SOD and CAT and the levels of AGE-R1 and GLO-1, which may be contributing to the antialbuminuric effect.

CONCLUSIONS

These findings demonstrate that lycopene may aggregate favorable effects to insulin against diabetic complications resulting from glycoxidative stress.

Carotenoid pattern intake and relation to metabolic status, risk and syndrome, and its components - divergent findings from the ORISCAV-LUX-2 survey

Carotenoids are generally associated with health-beneficial effects; however, their intake patterns related to the metabolic syndrome (MetS) and its components remain controversial. This cross-sectional study investigated associations between dietary intakes of individual carotenoids, fruits and vegetables, and the MetS and its components. Dietary intakes of 1346 participants of the Observation des Risques et de la Santé Cardio-Vasculaire au Luxembourg (ORISCAV-LUX-2) study were investigated by a 174-item FFQ, and carotenoid intake was determined by linking findings using mainly the USDA food databases. Components of MetS and complementary variables, including anthropometric (BMI, waist circumferences and waist:hip ratio) and biological parameters (TAG, HDL-cholesterol, fasting blood glucose and blood pressure), were measured. Logistic (for MetS) and linear multivariable regression models (including assessing MetS as scores) adjusted for various confounders were created. α-and β-Carotene, as well as lutein + zeaxanthin, were inversely associated with MetS (also when it was measured on a continuous scale), reducing the odds for MetS by up to 48 %. However, lycopene, phytoene and phytofluene were rather positively associated with MetS scores and its components, though these adverse effects disappeared, at least for lycopene, when controlling for intakes of tomato-based convenience foods, in line with indicating a rather unhealthy/westernised diet. All these associations remained significant when including fruits and vegetables as confounders, suggesting that carotenoids were related to MetS independently from effects within fruits and vegetables. Thus, a high intake of carotenoids was bidirectionally associated with MetS, its severity, risk and its components, depending on the type of carotenoid. Future investigations are warranted to explore the inverse role that tomato-based carotenoids appear to suggest in relation to the MetS.

Association between Tomato and Lycopene Consumption and Risk of All-Cause and Cause-Specific Mortality: Korean Genome and Epidemiology Study Cohort

SCOPE

Tomato has well-known beneficial health effects and is an important source of lycopene. The study aims to clarify the evidence for the association between tomato and lycopene consumption and all-cause and cause-specific mortality in Korean adults.

METHODS AND RESULTS

Data analyzed in the current study are obtained from the Korean Genome and Epidemiology Study Cohort. Mortality outcomes are determined based on death records from 2001 to 2020. Tomato and lycopene consumption is assessed using food frequency questionnaires and antioxidant databases and divided into quintiles. Over a mean follow-up of 11.5 years, 5863 deaths are recorded among 139913 participants aged over 40 years. Tomato consumption is not associated with the risk of all-cause and cancer mortality. However, the highest tomato consumption group has a lower risk of cardiovascular disease (CVD) mortality (HR = 0.779; 95% CI = 0.633, 0.957). Lycopene consumption is inversely associated with all-cause (HR = 0.872; 95% CI = 0.801, 0.950), and CVD (HR = 0.680; 95% CI = 0.548, 0.845) mortality.

CONCLUSION

A higher intake of tomatoes and lycopene is inversely related to the risk of CVD mortality, and lycopene consumption is associated with a lower risk of all-cause mortality.

Effect of Lycopene Intake on the Fasting Blood Glucose Level: A Systematic Review with Meta-Analysis

Lycopene is a lipophilic unsaturated carotenoid exhibiting a strong singlet oxygen-quenching ability. Herein, we investigated the effect of lycopene intake on the fasting blood glucose (FBG) level by conducting a systematic review and meta-analyses. We searched 15 databases (from the earliest date to June 2022 for PubMed or to August or September 2018 for the other databases) and included human interventional studies that assessed the effects of oral lycopene intake on FBG levels of participants ≥ 18 years of age. Three authors independently selected applicable studies and then assessed the study quality. Data were pooled as standardized mean difference (SMD) and analyzed by the random-effects model. Heterogeneity was assessed by I² statistics. A meta-analysis including 11 trial arms (n = 750) revealed a tendency towards a significant decrease in FBG level with not-important heterogeneity [SMD = -0.15 (95% CI: -0.31, 0.00), p = 0.05, I² = 9%]. Subgroup meta-analysis including two studies (n = 152) in type 2 diabetes patients revealed significantly decreased FBG levels with not-important heterogeneity [SMD = -0.37 (95% CI: -0.69, -0.05), p = 0.02, I² = 0%]. Most studies meeting the eligibility criteria had a moderate risk of bias. The funnel plot for FBG suggested an absence of publication bias. In conclusion, this systematic review and meta-analyses suggested that lycopene intake exerted an FBG-decreasing effect.

Effect of Lycopene Supplementation on Some Cardiovascular Risk Factors and Markers of Endothelial Function in Iranian Patients with Ischemic Heart Failure: A Randomized Clinical Trial

Aim

This study aimed to explore if supplementary lycopene tablets may help heart failure (HF) patients improve their lipid profile, BP, and the flow-mediated dilation (FMD) index for endothelial function.

Methods

Fifty patients with ischemic HF with a reduced ejection fraction (HFrEF) were randomly assigned to one of two groups: the lycopene group which received 25 mg lycopene tablets once a day for 8 weeks and the control group which received placebo tablets containing starch once a day for 8 weeks.

Results

Our results showed that after two months, the amount of triglyceride (TG) and FMD improved significantly compared to the control, TG decreased (219.27 vs. 234.24), and the mean of FMD increased (5.68 vs. 2.95). Other variables, including total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density cholesterol (HDL-C), systolic blood pressure (SBP), and diastolic blood pressure (DBP), showed no improvement. Also, only SBP and FMD showed intragroup improvement in the intervention group. In the intervention group, only SBP and FMD exhibited intragroup improvement.

Conclusions

It can be concluded that supplementing with lycopene can enhance endothelial function and reduce the TG levels in ischemic HFrEF patients. However, it had no positive effect on BP, TC, LDL-C, or HDL-C. Trial Registration. This clinical trial was registered at the Iranian Registry of Clinical Trials with IRCT registration number: IRCT20210614051574N4.