Evidence that the antioxidant flavonoids in tea and cocoa are beneficial for cardiovascular health

Potential Role of Dietary Phenolic Compounds in the Prevention and Treatment of Rheumatoid Arthritis: Current Reports

Rheumatoid arthritis (RA) is a complex illness with both hereditary and environmental components. Globally, in 2019, 18 million people had RA. RA is characterized by persistent inflammation of the synovial membrane that lines the joints, cartilage loss, and bone erosion. Phenolic molecules are the most prevalent secondary metabolites in plants, with a diverse spectrum of biological actions that benefit functional meals and nutraceuticals. These compounds have received a lot of attention recently because they have antioxidant, anti-inflammatory, immunomodulatory, and anti-rheumatoid activity by modulating tumor necrosis factor, mitogen-activated protein kinase, nuclear factor kappa-light-chain-enhancer of activated B cells, and c-Jun N-terminal kinases, as well as other preventative properties. This article discusses dietary polyphenols, their pharmacological properties, and innovative delivery technologies for the treatment of RA, with a focus on their possible biological activities. Nonetheless, commercialization of polyphenols may be achievable only after confirming their safety profile and completing successful clinical trials.

Therapeutic Potential of Catechin as an IKK-β Inhibitor for the Management of Arthritis: In vitro and In vivo Approach

Background

Rheumatoid arthritis (RA) is associated with increased levels of cytokines, for instance, nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and interleukin-1 (IL-1), which exhibit potent pro-inflammatory effects and are contributing factors to disease progression. A range of cytokines, cell adhesion molecules, and enzymes that are implicated in the debilitating effects of RA are transcribed by nuclear factor kappa.

Objectives

The purpose of this research was to characterize the efficacy of "catechin" as an IkappaB kinase-beta (IKK-β) inhibitor in collagen-induced arthritis (CIA) model in mice, as IKK-β is crucial in the transmission of signal-inducible NF-κβ activation.

Methods

Arthritis was brought on in Bagg and Albino, but it is written BALB/c (BALB/c) male mice through subcutaneous immunization with bovine type II collagen on days 0 and 21. Catechin is given orally every day after the onset of the disease. Clinical evaluation of the prevalence and severity of the condition was done throughout the trial, and biochemical testing was done at the end (day 42).

Results

In vitro findings of the study demonstrated catechin as a potent inhibitor of IKK-β with Half maximal Inhibitory Concentration (IC50) values of 2.90 μM and 4.358 μM in IKK-β and NF-κβ transactivation activity assay, respectively. Furthermore, catechin (dose range of 10-100 mg/kg, p.o.) was effective in reducing disease incidence and clinical signs in a dose-dependent manner, with an Effective Dose for 50% of the population (ED50) value of 79.579 mg/kg. The findings of this study demonstrate dose-dependent efficacy in terms of both disease severity (clinical scoring) and inflammatory markers (biochemical evaluation of the serum and joints).

Conclusions

IKK inhibitors are a prospective target for the creation of new therapeutics for arthritis and other inflammatory diseases because it has been suggested that this enzyme is crucial in the pathophysiology of RA. The finding of this study suggests that "catechin" represents a novel inhibitor of IKK-β with promising anti-inflammatory activity.

Potential Implication of in ovo Feeding of Phytogenics in Poultry Production

Hatchery's goals include maximizing revenue by achieving high hatchability with day-old birds of excellent quality. The advancement of technology has benefited the poultry sector since breeding and genetics technology have increased the rates of meat maturation in developing birds in a short period of time. Excessive use of in-feed antibiotics has been shown in studies to increase the chance of resistance to human infections. Bacterial resistance and antibiotic residues in animal products raised concerns about using antibiotics as growth promoters, eventually leading to a prohibition on using in-feed antibiotics in most industrialized nations. In ovo technology is a novel method for delivering bioactive chemicals to developing avian embryos. In ovo feeding technologies may provide additional nutrients to the embryos before hatching. The introduction of bioactive compounds has the potential to assist in decreasing and eventually eliminating the problems associated with traditional antibiotic delivery in chicken production. Phytobiotics were advocated as an alternative by researchers and dietitians. So far, several studies have been conducted on the use of phytogenic feed additives in poultry and swine feeding. They have primarily demonstrated that phytobiotics possess antibacterial, antioxidant, anti-inflammatory, and growth-stimulating properties. The antioxidant effect of phytobiotics can improve the stability of animal feed and increase the quality and storage duration of animal products. In general, the existing documentation indicates that phytobiotics improve poultry performance. To effectively and efficiently use the in ovo technique in poultry production and advance research in this area, it is important to have a thorough understanding of its potential as a means of nutrient delivery during the critical stage of incubation, its effects on hatching events and posthatch performance, and the challenges associated with its use. Overall, this review suggests that in ovo feeding of phytobiotics has the potential to improve the antioxidant status and performance of chickens.

Chemical Characterization, Antioxidant Capacity and Anti-Oxidative Stress Potential of South American Fabaceae Desmodium tortuosum

It has been proposed that oxidative stress is a pathogenic mechanism to induce cytotoxicity and to cause cardiovascular and neuronal diseases. At present, natural compounds such as plant extracts have been used to reduce the cytotoxic effects produced by agents that induce oxidative stress. Our study aimed to evaluate the antioxidant and cytoprotective capacity of Desmodium tortuosum (D. tortuosum) extract in the co- and pre-treatment in EA.hy926 and SH-SY5Y cell lines subjected to oxidative stress induced by tert-butylhydroperoxide (t-BOOH). Cell viability, reactive oxygen species (ROS), nitric oxide (NO), caspase 3/7 activity, reduced glutathione (GSH), glutathione peroxidase (GPx), glutathione reductase (GR), and molecular expression of oxidative stress biomarkers (SOD2, NRF2 and NFκB1) and cell death (APAF1, BAX, Caspase3) were all evaluated. It was observed that the D. tortuosum extract, in a dose-dependent manner, was able to reduce the oxidative and cytotoxicity effects induced by t-BOOH, even normalized to a dose of 200 µg/mL, which would be due to the high content of phenolic compounds mainly phenolic acids, flavonoids, carotenoids and other antioxidant compounds. Finally, these results are indicators that the extract of D. tortuosum could be a natural alternative against the cytotoxic exposure to stressful and cytotoxic chemical agents.

Oxidation of Quercetin and Kaempferol Markedly Amplifies Their Antioxidant, Cytoprotective, and Anti-Inflammatory Properties

The contention that flavonoids' oxidation would necessarily lead to a loss of their antioxidant properties was recently challenged by the demonstration that quercetin oxidation leads to the formation of 2-(3,4-dihydroxybenzoyl)-2,4,6-trihydroxy-3(2H)-benzofuranone (Que-BZF), a metabolite whose antioxidant potency was notably higher than that of its precursor. Here, we compared and expanded the former observation to that of the quercetin analogue kaempferol. Oxidation of kaempferol led to the formation of a mixture of metabolites that included the 2-(4-hydroxybenzoyl)-2,4,6-trihydroxy-3(2H)-benzofuranone (Kae-BZF). Following the chromatographic isolation of Kae-BZF from such a mixture, its antioxidant, mitochondria- and cell-protecting, and NF-kB-inhibiting effects were assessed, and compared with those of Que-BZF, in Caco-2 cells exposed to indomethacin as a source of ROS. The concentrations of Que-BZF (100 nm) and Kae-BZF (1 nm) needed to attain their maximal protection effects were 50- and 5000-fold lower than those of their respective precursors. The former differences in concentrations were also seen when the abilities of Que-BZF and Kae-BZF to inhibit the indomethacin-induced activation of NF-kB were compared. These data not only reveal that the oxidative conversion of quercetin and kaempferol into their respective 2-benzoyl-2-hydroxy-3(2H)-benzofuranones (BZF) results in a considerable amplification of their original antioxidant properties, but also that the in the case of kaempferol, such amplification is 100-fold greater than that of quercetin.

From Cocoa to Chocolate: Effect of Processing on Flavanols and Methylxanthines and Their Mechanisms of Action

Despite the health benefits associated with the ingestion of the bioactive compounds in cocoa, the high concentrations of polyphenols and methylxanthines in the raw cocoa beans negatively influence the taste, confer the astringency and bitterness, and affect the stability and digestibility of the cocoa products. It is, therefore, necessary to process cocoa beans to develop the characteristic color, taste, and flavor, and reduce the astringency and bitterness, which are desirable in cocoa products. Processing, however, affects the composition and quantities of the bioactive compounds, resulting in the modification of the health-promoting properties of cocoa beans and chocolate. In this advanced review, we sought to better understand the effect of cocoa's transformational process into chocolate on polyphenols and methylxanthine and the mechanism of action of the original flavanols and methylxanthines. More data on the cocoa processing effect on cocoa bioactives are still needed for better understanding the effect of each processing step on the final polyphenolic and methylxanthine composition of chocolate and other cocoa products. Regarding the mechanisms of action, theobromine acts through the modulation of the fatty acid metabolism, mitochondrial function, and energy metabolism pathways, while flavanols mainly act though the protein kinases and antioxidant pathways. Both flavanols and theobromine seem to be involved in the nitric oxide and neurotrophin regulation.

Response Surface Methodological Approach for Optimizing Theobroma cacao L. Oil Extraction

Theobroma cacao L. (Cocoa) is an agricultural product that is economically valuable worldwide; it is rich in bioactive compounds such as phenolic compounds and flavonoids. These compounds are known for their anti-inflammatory, anticarcinogenic, antimicrobial, antiulcer, and immune-modulating properties. Cocoa powder and cocoa butter are the major cocoa seed products, and cocoa seed oil (CSO) is the least-studied cocoa seed product. CSO is used in several industries; therefore, optimizing the extraction of high-quality CSO is essential. We used response surface methodology (RSM) to optimize the restriction dies, temperature, and sieve size to achieve a high yield and quality of CSO. The quality of the CSO was assessed according to total phenolic content (TPC), acid, and peroxide values, fatty acid content, and nitric oxide free radical scavenging activity. The highest yield (actual value: 46.10%; predicted value: 45.82%) was observed with the following restriction parameters: die size: 0.8 cm, temperature: 40 °C, and sieve size > 1.4 mm. The 2FI model for CSO extraction, the pressing time, the reduced quadratic model for acid value, the reduced cubic model for peroxide value, and the TPC showed that the model was significant. Our study primarily reported the impact of sieve size, restriction die, and temperature on CSO yield, acid, peroxide values, TPC of the CSO, and the influence of pressing time on the quantity and quality of the CSO. The high yield of CSO was of relatively lower quality. The temperature affected the yield, acid, peroxide values, TPC, and the nitric oxide free radical scavenging activity. In comparison, the fatty acid composition of the CSO was not affected by the processing temperature or sieve size. The results indicated that the extraction conditions must be chosen based on the application of the extracted oil. Further studies are warranted to confirm the results and further analyze other influential parameters during CSO extraction.

Cardioprotective Role of Theobroma cacao against Isoproterenol-Induced Acute Myocardial Injury

BACKGROUND

Antioxidants are beneficial in myocardial infarction (MI). It is suggestive that Theobroma cacao (TC) with rich antioxidant properties can be of health benefits in myocardial injury.

AIM

The study investigated the effect of Theobroma cacao on cardioprotection in isoproterenol-induced myocardial infarction in rats.

MATERIAL AND METHODS

Male Wistar rats divided into four groups of 6 rats were used for the study. In group 1, 0.9% normal saline placebo was administered via oral gavage to the control. Group 2 was the MI induced group that was given 100 mg/kg body weight isoproterenol subcutaneously twice at an interval of 24 hours. Group 3 was administered TC for 2 weeks at 100 mg/kg bodyweight via the oral route. Group 4 was pretreated with TC (100 mg/kg) via oral route for 2 weeks, immediately followed by the administration of 100 mg/kg body weight isoproterenol subcutaneously twice at an interval of 24 hours. The rats were sacrificed using chloroform anesthesia, and blood samples collected via cardiac puncture. The serum was analyzed for troponin level, lactate dehydrogenase (LDH), and malondialdehyde (MDA) level.

RESULTS

The serum troponin, LDH, and MDA levels were found to be significantly (p<0.01) increased in the MI group compared with the control. Pretreatment with TC before MI induction significantly (p<0.01) prevented increased serum troponin, LDH, and MDA levels when compared with the MI group. There was also a significant (p<0.01) decrease in MDA in the TC group compared with the control.

CONCLUSION

These results suggest that Theobroma cacao protects against isoproterenol-induced myocardial injury, possibly by preventing oxidative stress and consequent lipid peroxidation.

Chlorella vulgaris functional alcoholic beverage: Effect on propagation of cortical spreading depression and functional properties

Recent advances in microalgae biotechnology have proven that these microorganisms contain a number of bioactive molecules, that can be used as food additives that help prevent disease. The green microalga Chlorella vulgaris presents several biomolecules, such as lutein and astaxanthin, with antioxidant capacity, which can play a protective role in tissues. In this study, we produced and analyzed a C. vulgaris functional alcoholic beverage (produced using a traditional Brazilian alcoholic beverage, cachaça, and C. vulgaris biomass). Assays were conducted in vitro by radical scavenging tests, and in vivo, by modeling cortical spreading depression in rat brains. Scavenging radical assays showed that consumption of the C. vulgaris alcoholic beverage had a DPPH inhibition of 77.2%. This functional alcoholic beverage at a concentration of 12.5 g L^-1 significantly improved cortical spreading depression velocity in the rat brains (2.89 mm min^-1), when compared with cachaça alone (3.68 mm min^-1) and control (distilled water; 3.25 mm min^-1). Moreover, animals that consumed the functional beverage gained less weight than those that consumed just alcohol and the control groups. These findings suggest that the C. vulgaris functional alcoholic beverage plays a protective physiologic role in protecting brain cells from the effects of drinking ethanol.

Investigation of potential inhibitor properties of ethanolic propolis extracts against ACE-II receptors for COVID-19 treatment by molecular docking study

The angiotensin-converting enzyme (ACE)-related carboxypeptidase, ACE-II, is a type I integral membrane protein of 805 amino acids that contains 1 HEXXH-E zinc binding consensus sequence. ACE-II has been implicated in the regulation of heart function and also as a functional receptor for the coronavirus that causes the severe acute respiratory syndrome (SARS). In this study, the potential of some flavonoids presents in propolis to bind to ACE-II receptors was calculated with in silico. Binding constants of ten flavonoids, caffeic acid, caffeic acid phenethyl ester, chrysin, galangin, myricetin, rutin, hesperetin, pinocembrin, luteolin and quercetin were measured using the AutoDock 4.2 molecular docking program. And also, these binding constants were compared to reference ligand of MLN-4760. The results are shown that rutin has the best inhibition potentials among the studied molecules with high binding energy − 8.04 kcal/mol, and it is followed by myricetin, quercetin, caffeic acid phenethyl ester and hesperetin. However, the reference molecule has binding energy of – 7.24 kcal/mol. In conclusion, the high potential of flavonoids in ethanolic propolis extracts to bind to ACE-II receptors indicates that this natural bee product has high potential for COVID-19 treatment, but this needs to be supported by experimental studies.

New Highlights of Resveratrol: A Review of Properties against Ocular Diseases

Eye diseases are currently a major public health concern due to the growing number of cases resulting from both an aging of populations and exogenous factors linked to our lifestyles. Thus, many treatments including surgical pharmacological approaches have emerged, and special attention has been paid to prevention, where diet plays a preponderant role. Recently, potential antioxidants such as resveratrol have received much attention as potential tools against various ocular diseases. In this review, we focus on the mechanisms of resveratrol against ocular diseases, in particular age-related macular degeneration, glaucoma, cataract, diabetic retinopathy, and vitreoretinopathy. We analyze, in relation to the different steps of each disease, the resveratrol properties at multiple levels, such as cellular and molecular signaling as well as physiological effects. We show and discuss the relationship to reactive oxygen species, the regulation of inflammatory process, and how resveratrol can prevent ocular diseases through a potential epigenetic action by the activation of sirtuin-1. Lastly, various new forms of resveratrol delivery are emerging at the same time as some clinical trials are raising more questions about the future of resveratrol as a potential tool for prevention or in therapeutic strategies against ocular diseases. More preclinical studies are required to provide further insights into RSV's potential adjuvant activity.

Citral Protects Human Endothelial Cells Against Hydrogen Peroxide-induced Oxidative Stress

OBJECTIVES

Oxidative stress plays a major role in endothelial dysfunction. Citral is a monoterpene aldehyde with antioxidant properties. This study aimed to investigate the effect of citral on human umbilical vein endothelial cells (HUVECs) under hydrogen peroxide (H2O2)-induced oxidative stress.

MATERIALS AND METHODS

The cells were treated with citral (0.625-10 μg/mL) for 24 h before exposure to H2O2 (0.5 mM, 2 h). Cell viability was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay. The hydroperoxide concentrations and ferric reducing ability of plasma (FRAP) were measured in intra- and extracellular fluids.

RESULTS

Pretreatment of HUVECs with citral at concentrations of 5 and 10 μg/mL significantly enhanced the cell viability in H2O2-induced cytotoxicity. It reduced intracellular hydroperoxide levels at the concentrations of 5 and 10 μg/mL and extracellular hydroperoxide levels at the concentrations of 2.5-10 μg/mL. Pretreatment with citral significantly increased the FRAP value in intra- and extracellular fluids at the concentration range of 1.25-10 μg/mL.

CONCLUSION

Antioxidant and cytoprotective effects were found for citral against oxidative damage induced by H2O2 in human endothelial cells. However, more studies in this area are needed to assess its clinical value for prevention and treatment of cardiovascular diseases.

Therapeutic Potential of Quercetin as an Antiatherosclerotic Agent in Atherosclerotic Cardiovascular Disease: A Review

Atherosclerotic cardiovascular disease (ASCVD) is one of the diseases with the highest morbidity and mortality globally. It causes a huge burden on families and caregivers and high costs for medicine and surgical interventions. Given expensive surgeries and failures of most conventional treatments, medical community tries to find a more cost-effective cure. Thus, attentions have been primarily focused on food or herbs. Quercetin (Qu) extracted from food, a flavonoid component, develops potentials of alternative or complementary medicine in atherosclerosis. Due to the wide range of health benefits, researchers have considered to apply Qu as a natural compound in therapy. This review is aimed to identify the antiatherosclerosis functions of Qu in treating ASCVD such as anti-inflammatory, antioxidant properties, effects on endothelium-dependent vasodilation, and blood lipid-lowering.

Effect of dietary inclusion of almond fruit on sexual behavior, arginase activity, pro-inflammatory, and oxidative stress markers in diabetic male rats

This study was designed to examine the effect of almond-included diets on sexual behavior, arginase activity, and pro-inflammatory markers in diabetic male rats. Forty-two male rats were divided into seven groups (n = 6). Diabetes was triggered via a single dose intraperitoneal injection of streptozotocin (50 mg/kg). Diabetes was confirmed 72 hr after STZ induction, and animals with blood glucose ≥ 250 mg/dl were considered diabetic and used for the experiment. The effects of almond-supplemented diets on glucose level, sexual function, NF-κB and TNF-α levels, arginase and purinergic enzyme activities, and levels of oxidative stress markers were assessed. A significant decrease in sexual activities with a simultaneous increase in pro-inflammatory markers, arginase and purinergic enzyme activities as well as TBARS and ROS levels was observed in diabetic rats. Interestingly, treatment with supplemented diets ameliorated the effects. Conclusively, intake of almonds could prevent the risk of erectile dysfunction in diabetic subjects. PRACTICAL APPLICATIONS: Intake of diets rich in fruits, nuts, and vegetables has been reported to reduce the risk of metabolic syndrome. Here, we investigate the effect of dietary inclusion of almond fruit on sexual behavior, arginase activity, oxidative stress, and pro-inflammatory markers in diabetic male rats. Interestingly, data generated from this work reveal that the supplemented diets enhanced sexual activities, and reduced oxidative stress and pro-inflammatory markers in diabetic male rats. Thus, consumption of almond (drupe and seed) could prevent/reduce the erectile dysfunction in individual with diabetes.

Cocoa Bean Shell-A By-Product with Nutritional Properties and Biofunctional Potential

Cocoa bean shells (CBS) are one of the main by-products from the transformation of cocoa beans, representing 10%‒17% of the total cocoa bean weight. Hence, their disposal could lead to environmental and economic issues. As CBS could be a source of nutrients and interesting compounds, such as fiber (around 50% w/w), cocoa volatile compounds, proteins, minerals, vitamins, and a large spectrum of polyphenols, CBS may be a valuable ingredient/additive for innovative and functional foods. In fact, the valorization of food by-products within the frame of a circular economy is becoming crucial due to economic and environmental reasons. The aim of this review is to look over the chemical and nutritional composition of CBS and to revise the several uses that have been proposed in order to valorize this by-product for food, livestock feed, or industrial usages, but also for different medical applications. A special focus will be directed to studies that have reported the biofunctional potential of CBS for human health, such as antibacterial, antiviral, anticarcinogenic, antidiabetic, or neuroprotective activities, benefits for the cardiovascular system, or an anti-inflammatory capacity.

Association between chocolate consumption frequency and heart rate variability indices

BACKGROUND

Previous studies have shown favorable effects of chocolate products on the cardiovascular system and reported an inverse relationship between chocolate consumption and adverse cardiac events; however, relationships between chocolate eating habits and heart rate variability have not yet been studied. The purpose of the present research was to determine the relationship, if any, between chocolate consumption frequency and heart rate variability.

METHODS

A cross-sectional study was carried out in a group of 98 young females (19-21 years old). The study included the evaluation of chocolate eating habits by a questionnaire and heart rate variability parameters by Finometer and Powerlab as primary outcomes along with measuring anthropometry, blood pressure and fasting blood sugar levels as predictors to account for potential confounding.

RESULTS

Three chocolate eating patterns were distinguished: "No regular chocolate consumption (n:42), 2-4 servings/week (n:20), 5 or more servings/week (n:36)". An ANOVA test revealed insignificant differences (p > 0.05) in heart rate variability parameters (time domain: Heart rate, RRms, SDNN, RMSSD; frequency domain: LF, HF, LF/HF) and pressures (systolic, diastolic, pulse, mean arterial) among three groups of individuals having different chocolate eating habits. Relative frequency of chocolate intake did not correlate with any of the cardiovascular, time-domain or frequency-domain parameters of heart rate variability in study participants.

CONCLUSION

Based on our results, we conclude that relative frequency of chocolate eating may not affect autonomic regulation of the heart in young females. Also, it may have no correlation with any of the cardiovascular, time-domain or frequency-domain parameters of heart rate variability.

Farrerol Directly Targets GSK-3β to Activate Nrf2-ARE Pathway and Protect EA.hy926 Cells against Oxidative Stress-Induced Injuries

Oxidative stress-mediated endothelial injury is considered to be involved in the pathogenesis of various cardiovascular diseases. Farrerol, a typical natural flavanone from the medicinal plant Rhododendron dauricum L., has been reported to show protective effects against oxidative stress-induced endothelial injuries in our previous study. However, its action molecular mechanisms and targets are still unclear. In the present study, we determined whether farrerol can interact with glycogen synthase kinase 3β- (GSK-3β-) nuclear factor erythroid 2-related factor 2- (Nrf2-) antioxidant response element (ARE) signaling, which is critical in defense against oxidative stress. Our results demonstrated that farrerol could specifically target Nrf2 negative regulator GSK-3β and inhibit its kinase activity. Mechanistic studies proved that farrerol could induce an inhibitory phosphorylation of GSK-3β at Ser9 without affecting the expression level of total GSK-3β protein and promote the nuclear translocation of Nrf2 as well as the mRNA and protein expression of its downstream target genes heme oxygenase-1 (HO-1) and NAD(P)H: quinone oxidoreductase 1 (NQO1) in EA.hy926 cells. Further studies performed with GSK-3β siRNA and specific inhibitor lithium chloride (LiCl) confirmed that GSK-3β inhibition was involved in farrerol-mediated endothelial protection and Nrf2 signaling activation. Moreover, molecular docking and molecular dynamics studies revealed that farrerol could bind to the ATP pocket of GSK-3β, which is consistent with the ATP-competitive kinetic behavior. Collectively, our results firstly demonstrate that farrerol could attenuate endothelial oxidative stress by specifically targeting GSK-3β and further activating the Nrf2-ARE signaling pathway.

Association between Dietary Intakes of Tea, Coffee, and Soft Drinks in Patients Undergoing Coronary Angiography with Coronary Artery Stenosis

Background:

Coronary artery disease (CAD) is one of the major causes of mortality that is related to the nutritional habits and lifestyle. The aim of this study was to examine the association between tea, coffee, and soft drink consumption and coronary artery stenosis in patients undergoing coronary angiography.

Methods:

Out of all the patients, 208 cases (101 Female) with 57.81 ± 12.18 (mean ± SD) were assigned to participate in this cross-sectional study. In total, 168-items, semi-quantitative food frequency questionnaire collected for assessments of dietary intakes of black tea, coffee, caffeine, and soft drinks and record demographic and clinical questionnaire.

Results:

There were negative association between arteries with stenosis of more than 50% number with dietary intakes of tea (P = 0.011, r = – 0.187), coffee (P = 0.069, r = – 0.098) intakes, and dietary caffeine intake (P = 0.043, r = –0.118). The high consumptions of soft drinks (P = 0.005, r = 0.387) were associated with an enhancement in arteries with stenosis of more than 50% number. In addition, dietary consumption of black tea have a negatively significant association with the history of previous angiography (P = 0.044, r = –0.121), the history of previous Stanton (P = 0.035, r = –0.132), and coronary artery bypass graft surgery nomination (P = 0.008, r = –0.216). Coffee consumption showed a significant negative relationship with engagement for coronary artery bypass graft surgery (P = 0.004, r = –0.598).

Conclusions:

Dietary intakes of tea, coffee, and caffeine may have a negative relationship with CAD and cardio vascular diseases. Healthy dietary lifestyle is an important issue for the prevention of chronic diseases.

Bioavailability and metabolism of selected cocoa bioactive compounds: A comprehensive review

Cocoa beans and their co-products are a rich source of beneficial compounds for health promotion, including polyphenols and methylxanthines. Knowledge of bioavailability and in vivo bioactivity of these phytochemicals is crucial to understand their role and function in human health. Therefore, many studies concerning bioavailability and bioactivity of cocoa bioactive compound have been done in both in vivo animal models and in humans. This critical review comprehensively summarizes the existing knowledge about the bioavailability and the major metabolic pathways of selected cocoa bioactive compounds (i.e. monomeric flavan-3-ols, procyanidins, anthocyanins, flavonols, phenolic acids, N-phenylpropenoyl-L-amino acids, stilbenes, and methylxanthines). The compiled results indicated that many of these compounds undergo extensive metabolism prior to absorption. Different factors have been suggested to influence the bioavailability of polyphenols and methylxanthines among them the role of gut microbiota, structure of these compounds, food matrix and occurrence of other substances were the most often considered. Aforementioned factors decided about the site where these bioactive compounds are digested and absorbed from the alimentary tract, as well as the pathway by which they are metabolized. These factors also determine of the type of transport through the intestine barrier (passive, involving specific enzymes or mediated by specific transporters) and their metabolic path and profile.

Acute study of dose-dependent effects of (-)-epicatechin on vascular function in healthy male volunteers: A randomized controlled trial

BACKGROUND & AIMS

There is convincing clinical evidence to suggest that flavanol-containing foods/beverages are capable of inducing improvements in human vascular function. However, whilst (-)-epicatechin has been tested for efficacy, a full dose-dependency has yet to be established, particularly at doses below 1 mg/kg BW. The current study examined the dose-dependent effects of (-)-epicatechin on human vascular function with concurrent measurement of plasma (-)-epicatechin metabolites and levels of circulating nitrite and nitrate species, NO_x.

METHODS

An acute, double-blind, placebo-controlled, crossover intervention trial was conducted in 20 healthy males with 4 treatment arms: water-based (-)-epicatechin (0.1, 0.5 and 1.0 mg/kg BW) and a water only as control. Vascular function was assessed by flow-mediated dilatation (FMD) measured at the brachial artery, laser Doppler imaging with iontophoresis (LDI) at the subcutaneous capillaries of the forearm (response to Ach and SNP) and peripheral blood pressure (BP) at baseline, 1, 2, 4 and 6 h post-intervention. Plasma analysis of epicatechin metabolites was conducted by LC-MS and circulating plasma of nitrite and nitrate species were performed using an HPLC-based system (ENO-30).

RESULTS

Significant increases in % FMD were found to occur at 1 and 2 h following intake of 1 mg/kg BW, and at 2 h for the 0.5 mg/kg BW intake. There were no significant changes in LDI or BP at any time-points or intake levels. Increases in FMD over the 6 h timeframe were closely paralleled by the appearance of total plasma (-)-epicatechin metabolites. Non-significant changes in circulating NOx was observed.

CONCLUSIONS

Our data add further evidence that (-)-epicatechin is a causal vasoactive molecule within flavanol-containing foods/beverages. In addition, we show for the first time that intake levels as low as 0.5 mg/kg BW are capable of inducing acute improvements in vascular function (FMD) in healthy volunteers.

Antimicrobial Activities of Tea Polyphenol on Phytopathogens: A Review

The use of natural antimicrobial compounds in crop production has gained much attention from consumers and the agricultural industry. Consequently, interest in more natural, non-synthetic antimicrobials as potential alternatives to conventional chemical pesticides to combat phytopathogens has heightened. Tea polyphenol (TP), a unique and highly important functional component of tea plants, has been reported to possess antimicrobial properties against a wide spectrum of plant pathogens. The aim of this review is to discuss the emerging findings on the mechanisms of antimicrobial action, and the antimicrobial properties of TP, including their major components, effectiveness, and synergistic effects. More studies, particularly field studies, are still necessary to establish conclusive evidence for the effectiveness of TP against phytopathogens. However, the basic conclusion from existing studies suggests that TP is a potential antimicrobial agent for pesticide reduction in agricultural systems.

Enhanced susceptibility to apoptosis and growth arrest of human breast carcinoma cells treated with silica nanoparticles loaded with monohydroxy flavone compounds

The treatment of drug-resistant cancer is a clinical challenge, hence screening for novel anticancer drugs is critically important. In this study, we investigated the anti-tumor potential of three plant-derived flavone compounds: 3-hydroxy flavone (3-HF), 6-hydroxy flavone (6-HF), and 7-hydroxy flavone (7-HF), either alone or combined with silica nanoparticles (3-HF + NP, 6-HF + NP, and 7-HF + NP), on the human breast carcinoma cell lines MDA-MB-231 and MCF-7, as well as on non-tumorigenic normal breast epithelial cells (MCF-10). The IC₅₀ values of these flavone compounds loaded with NP (flavones + NP) in these cell lines were determined to be 1.5 μg/mL without affecting the viability of normal MCF-10 cells. Additionally, using annexin V - propidium iodide double-staining followed by flow cytometry analysis, we found that the combination of flavones with NP significantly induced apoptosis in MCF-7 and MDA-MB-231 cancer cells. Furthermore, flavones + NP increased the expression of cytochrome c and caspase-9, mediating the growth arrest of these cancer cells. Most importantly, the combination of flavones with NP significantly abolished the expression of ATF-3, which is responsible for the proliferation and invasion of bone-metastatic breast cancer cells. Our data revealed the potential therapeutic effects of these flavones in fighting breast cancer cells, and provide the first insights concerning the underlying molecular mechanisms.

The effects of five types of tea solutions on epiboly process, neural and cardiovascular development, and locomotor capacity of zebrafish

The effects of teas on embryonic development are still known little. The objective of this study was to compare and analyze developmental effects of green tea, delicate flavor oolong tea, strong flavor oolong tea, black tea, and pu'er tea using zebrafish embryos. Embryos were exposed in tea solutions from one-cell stage; the morphology, locomotor capacity, and gene expression of embryos or larvae were analyzed. The results showed that either tea could decrease the length of body and the size of head and eyes. The effect of green tea had the most significant effects on morphology. Only green tea disturbed cell movement, epiboly, and nervous system development. All five tea solutions caused heart structure alternations and lowered heart rates, and effects caused by green tea were severe. Green tea inhibited the formation of dorsal aorta and segmental arteries and decreased the velocity and total movement distance of larvae. In conclusion, the toxicity of green tea to epiboly, neural and cardiovascular development, and locomotor capacity is more severe than that of other teas. Our study played a warning role for safety consumption of teas and provided references for further study of tea's physiological and pharmacological effects and biological activity.

The Effect of Aerobic Training and Green Tea Supplementation on Cardio Metabolic Risk Factors in Overweight and Obese Females: A Randomized Trial

BACKGROUND

The use of exercise along with green tea supplements has been shown to have beneficial effects on obesity and its complications.

OBJECTIVES

This study aimed at exploring the effect of aerobic training (AT) and green tea (GT) supplementation on body composition, blood lipids, blood glucose, and cardiovascular risk factors in overweight and obese females.

METHODS

Thirty-nine healthy non-athlete overweight and obese females with an average age of 28.11 ± 6.50 years were sampled and randomly assigned to control (n = 13), AT (n = 13), and AT + GT (n = 13). Participants of the latter group received 33 mg of green tea after each main meal every day, and in addition, they were subjected to AT for eight weeks, including three 90-minute training sessions that were progressive, reaching 80% of the target heart rate (THR). Blood samples were taken from participants one week before the initiation of the study and 48 hours after the last training session.

RESULTS

Compared to the control group, body weight, body fat percentage, body mass index (BMI), triglyceride, low-density lipoprotein, blood pressure, and heart rate (HR) significantly decreased in the groups treated with AT and AT + GT (P < 0.05). However, no significant changes occurred in FBS, HDL, TC, and WHR (P > 0.05).

CONCLUSIONS

AT was effective in modifying cardiovascular risk factors, e.g. hypertension, heart rate (HR), triglyceride, and low-density lipoprotein (LDL). However, GT addition was not effective. Considering Iranians' high tendency towards the consumption of plant materials, this finding needs further investigation.

Plant Seed Proteins: Chemistry, Technology and Applications

This review deals with the significance of plant seed proteins. Plant seed proteins are known to provide various beneficial activities like antimicrobial, antihypertensive, antiviral and antioxidant. They are essential source of amino acids; act as a source of nutrition booster. Present review elaborates on extraction of proteins and hydrolysis with their advantages and disadvantages, their nutritional property, health benefits and challenges associated with the peptides.

Relationship between the Physiochemical Properties of Cocoa Procyanidins and Their Ability to Inhibit Lipid Oxidation in Liposomes

The aim of this paper is to evaluate the effects of cocoa polyphenols and procyanidins with different degrees of polymerization that are encapsulated in liposome delivery systems on the inhibition of lipid oxidation at pH 3.0 and 5.0. In general, liposomes at pH 3.0 and 5.0 were physically stable in the presence of polyphenols and procyanidins with mean particle sizes of 56.56 ± 12.29 and 77.45 ± 8.67 nm and ζ-potentials of -33.50 ± 3.16 and -20.44 ± 1.98 mV at pH 3.0 and 5.0, respectively. At both pH 3.0 and pH 5.0, all the polyphenols and procyanidins inhibited lipid hydroperoxide and hexanal formation, and antioxidant activities increased with increasing polymer-chain sizes. The greater antioxidant activities of the isolated procyanidins were likely due to their increased metal-chelating capacities, as determined by ferric-reducing-ability (FRAP) assays, and their greater levels of partitioning into the lipids, as determined by their log K_ow values and encapsulation efficiencies. The crude extract had the greatest antioxidant activity, which could be because other antioxidants were present, or combinations of the different polyphenols and procyanidins inhibited lipid oxidation synergistically.

Natural products targeting ER stress pathway for the treatment of cardiovascular diseases

Endoplasmic reticulum (ER) is the main organelle for the synthesis, folding, and processing of secretory and transmembrane proteins. Pathological stimuli including hypoxia, ischaemia, inflammation and oxidative stress interrupt the homeostatic function of ER, leading to accumulation of unfolded proteins, a condition referred to as ER stress. ER stress triggers a complex signalling network referred as the unfolded protein response (UPR). Extensive studies have demonstrated that ER stress plays an important role in the pathogenesis of various cardiovascular diseases such as heart failure, ischemic heart disease and atherosclerosis. The importance of natural products in modern medicine are well recognized and continues to be of interests as a source of novel lead compounds. Natural products targeting components of UPR and reducing ER stress offers an innovative strategic approach to treat cardiovascular diseases. In this review, we discussed several therapeutic interventions using natural products with potential cardiovascular protective properties targeting ER stress signalling pathways.

Malus sieversii: the origin, flavonoid synthesis mechanism, and breeding of red-skinned and red-fleshed apples

Flavonoids play essential roles in human health. Apple (Malus domestica Borkh.), one of the most widely produced and economically important fruit crops in temperate regions, is a significant source of flavonoids in the human diet and is among the top nutritionally rated and most widely consumed fruits worldwide. Epidemiological studies have shown that the consumption of apples, which are rich in a variety of free and easily absorbable flavonoids, is associated with a decreased risk of various diseases. However, apple production is challenged by serious inbreeding problems. The narrowing of the hereditary base has resulted in apples with poor nutritional quality and low flavonoid contents. Recently, there have been advances in our understanding of the roles that Malus sieversii (Ledeb.) M.Roem has played in the process of apple domestication and breeding. In this study, we review the origin of cultivated apples and red-fleshed apples, and discuss the genetic diversity and construction of the core collections of M. sieversii. We also discuss current research progress and breeding programs on red-skinned and red-fleshed apples and summarize the exploitation and utilization of M. sieversii in the breeding of high-flavonoid, and red-fleshed apples. This study highlights a valuable pattern of horticultural crop breeding using wild germplasm resources. The future challenges and directions of research on the molecular mechanisms of flavonoid accumulation and high-flavonoid apple breeding are discussed.

Do flavanols-rich natural products relieve obesity-related insulin resistance?

Growing evidence support that insulin resistance may occur as a severe problem due to chronic energetic overfeeding and subsequent obesity. When an abundance of glucose and saturated fat enter the cell, impaired blood flow, hypoxia, inflammation and macrophage infiltration in obese adipose tissue may induce oxidative stress and insulin resistance. Excessive circulating saturated fatty acids ectopically accumulate in insulin-sensitive tissues and impair insulin action. In this context, excessive hepatic lipid accumulation may play a central, pathogenic role in insulin resistance. It is thought that dietary polyphenols may ameliorate obesity-related insulin resistance by attenuating inflammatory responses and oxidative stress. The most often occurring natural polyphenolic compounds are flavonoids. In this review, the possible mechanistic effect of flavonoid-rich natural products on insulin resistance-related metabolic pathways is discussed. Polyphenol intake can prevent high-fat-diet-induced insulin resistance via cell surface G protein-coupled estrogen receptors by upregulating the expression of related genes, and their pathways, which are responsible for the insulin sensitivity.

Polyphenols from Root, Tubercles and Grains Cropped in Brazil: Chemical and Nutritional Characterization and Their Effects on Human Health and Diseases

Throughout evolution, plants have developed the ability to produce secondary phenolic metabolites, which are important for their interactions with the environment, reproductive strategies and defense mechanisms. These (poly)phenolic compounds are a heterogeneous group of natural antioxidants found in vegetables, cereals and leguminous that exert beneficial and protective actions on human health, playing roles such as enzymatic reaction inhibitors and cofactors, toxic chemicals scavengers and biochemical reaction substrates, increasing the absorption of essential nutrients and selectively inhibiting deleterious intestinal bacteria. Polyphenols present in some commodity grains, such as soy and cocoa beans, as well as in other vegetables considered security foods for developing countries, including cassava, taro and beetroot, all of them cropped in Brazil, have been identified and quantified in order to point out their bioavailability and the adequate dietary intake to promote health. The effects of the flavonoid and non-flavonoid compounds present in these vegetables, their metabolism and their effects on preventing chronic and degenerative disorders like cancers, diabetes, osteoporosis, cardiovascular and neurological diseases are herein discussed based on recent epidemiological studies.

Cacao Phylloplane: The First Battlefield against Moniliophthora perniciosa, Which Causes Witches' Broom Disease

The phylloplane is the first contact surface between Theobroma cacao and the fungus Moniliophthora perniciosa, which causes witches' broom disease (WBD). We evaluated the index of short glandular trichomes (SGT) in the cacao phylloplane and the effect of irrigation on the disease index of cacao genotypes with or without resistance to WBD, and identified proteins present in the phylloplane. The resistant genotype CCN51 and susceptible Catongo presented a mean index of 1,600 and 700 SGT cm^-2, respectively. The disease index in plants under drip irrigation was reduced by approximately 30% compared with plants under sprinkler irrigation prior to inoculation. Leaf water wash (LWW) of the cacao inhibited the germination of spores by up to 98%. Proteins from the LWW of CCN51 were analyzed by two-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis followed by tandem mass spectrometry. The gel showed 71 spots and identified a total of 42 proteins (28 from the plant and 14 from bacteria). Proteins related to defense and synthesis of defense metabolites and involved in nucleic acid metabolism were identified. The results support the hypothesis that the proteins and water-soluble compounds secreted to the cacao phylloplane participate in the defense against pathogens. They also suggest that SGT can contribute to the resistance of cacao.

Differential roles of 3-Hydroxyflavone and 7-Hydroxyflavone against nicotine-induced oxidative stress in rat renal proximal tubule cells

Plant flavonoids are well known as antioxidants against oxidative stress induced by exposure to external pollutants. Nicotine (NIC) is one of those agents which increases renal oxidative stress, an important factor in the pathogenesis of renal epithelial injury in smokers. Although several studies had been conducted on flavonoids and oxidative stress, the mechanism of the protective pathways are not fully understood. Here, we present studies on antioxidant properties of two mono-hydroxyflavone isomers, 3-hydroxyflanove (3HF)- and 7-hydroxyflavone (7HF), against nicotine-associated oxidative stress and injury in cultured renal proximal tubule cells and correlate their antioxidant properties with their chemical structure. Our data clearly demonstrates, for the first time, that while both 3HF and 7HF protect renal cells from NIC-associated cytotoxicity, the mechanism of their action is different: 3HF elicits protective activity via the PKA/CREB/MnSOD pathway while 7HF does so via the ERK/Nrf2/HO-1 pathway. Molecular docking and dynamics simulations with two major signaling pathway proteins showed significant differences in the binding energies of 3HF (-5.67 and -7.39 kcal.mol-1) compared to 7HF (-5.41 and -8.55 kcal.mol-1) in the matrices of CREB and Keap1-Nrf2 proteins respectively, which corroborate with the observed differences in their protective properties in the renal cells. The implications of this novel explorative study is likely to promote the understanding of the mechanisms of the antioxidative functions of different flavones.

Effect of Diabetea tea ™ consumption on inflammatory cytokines and metabolic biomarkers in type 2 diabetes patients

ETHNOPHARMACOLOGICAL RELEVANCE

Diabetea tea™ (DT) is an anti-diabetic alternative medicine in some Asian countries. The main constituent of DT is black tea originating from Camellia sinensis that is supplemented by 12 other medicinal plants. Black tea contains a large amount of the flavonoids catechins especially epigallocatechin gallate (EGCG) which has anti-inflammatory and antioxidative capacity. This study was undertaken to evaluate the possible effects of DT intake on inflammatory cytokines, regulatory T cells (Tregs) and metabolic biomarkers in T2DM.

MATERIALS AND METHODS

The study included 50 patients with T2DM. The patients had received 3 cups (600ml) of DT extract or placebo (PL) extract per day during a period of 12 weeks. Intracellular cytokine expression in peripheral blood mononuclear cell (PBMC) as well as the glycemic and lipid profiles were measured at baseline and after the treatment period. The active constituents of the medicinal plants included in DT were investigated by gas chromatography-mass spectrometry (GC/MS).

RESULTS

Ingestion of DT suppressed CD4+ T cell expression of IL-1β and Il-8 (p<0.05) and up-regulated the expression of IL-10 and the Treg/IL-17 ratio (p<0.05) which was not shown in PL. A significant decrease in HbA1c and LDL was observed at the end of the study period (p<0.05) in DT. The GC/MS analyses of DT indicated the presence of lupeol, β-Amyrin and β-sitosterol. Also analyses of individual herbs showed the presence of higher levels of lupeol and β-Amyrin in Nuga Ficus bengalensis and β-sitosterol in the Attikka Ficus racemosa, indicating that the active ingredients of DT are concentrated in these two herbs.

CONCLUSION

The present study provides evidence that DT has hypoglycemic and antihyperlipidemic properties. Interestingly, DT has anti-inflammatory effects. These properties are attributed to the flavonoids, triterpenes and phytosterol contents of the tea. We suggest that DT protects against diabetes complications in the long term.

Pentameric Procyanidins Isolated from Theobroma cacao Seeds Selectively Downregulate ErbB2 in Human Aortic Endothelial Cells

Flavonoids isolated from cocoa have biological activities relevant to oxidant defenses, vascular health, tumor suppression, and immune function. The intake of certain dietary flavonoids, along with other dietary substances such as tocopherols, ascorbate, and carotenoids, is epidemiologically associated with a reduced risk of cardiovascular disease. Flavonoids have also been shown to modulate tumor pathology in vitro and in animal models. We took advantage of the conserved sequences found in tyrosine kinases to study the influence of cocoa fractions and controls on gene expression. We report that the pentameric procyanidin (molecular weight of 1442 daltons) fraction isolated from cocoa was a potent inhibitor of tyrosine kinase ErbB2 expression, a receptor important in angiogenesis regulation. Consistent with this primary observation, the cocoa flavonoid fraction also suppressed human aortic endothelial cell (HAEC) growth and decreased expression of two tyrosine kinases responsive to ErbB2 modulation, namely VEGFR-2/KDR and MapK 11/p38β2. These inhibitory effects were observed when HAECs were treated with the flavonol fraction (molecular weight 280 daltons) isolated from cocoa, which comprise the structural subunits from which the procyanidin flavonoid subclass is biosynthetically constructed. Down-regulation of ErbB2 and inhibition of HAEC growth by cocoa procyanidins may have several downstream implications, including reduced vascular endothelial growth factor (VEGF) activity and angiogenic activity associated with tumor pathology. These results suggest specific dietary flavonoids are capable of selectively inhibiting ErbB2 and therefore may offer important insight into the design of therapeutic agents that target tumors overexpressing ErbB2.

Effect of oral theaflavin administration on body weight, fat, and muscle in healthy subjects: a randomized pilot study

Theaflavins are reddish-colored polyphenols in black tea. To test the efficacy of theaflavin administration on body fat and muscle, we performed a randomized, double-blind, placebo-controlled study and investigated the effect of theaflavins administration on the body composition using of healthy subjects. In this study, 30 male and female Japanese were enrolled and participants were randomly allocated to receive placebo, theaflavin (50 or 100 mg/day), or catechin (400 mg/ml) for 10 weeks. The effects were evaluated using body weight, body fat percentage, subcutaneous fat percentage, and skeletal muscle percentage. Theaflavin administration significantly improved body fat percentage, subcutaneous fat percentage, and skeletal muscle percentage when compared to with the placebo. In contrast, there was no significant difference in all measured outcomes between the catechin and the placebo groups. The results indicate that oral administration of theaflavin had a beneficial effect on body fat and muscle in healthy individuals.

Antithrombotic activity of Vitis labrusca extract on rat platelet aggregation

Vitis labrusca is a grapevine that has antioxidant, neuroprotective, hepatoprotective, and anticarcinogenic activity. However, the antithrombotic effect of Vitis labrusca leaves on platelets is yet to be ascertained. We investigated the inhibitory effect of V. labrusca leaf extract (VLE) on platelet aggregation in vitro and ex vivo. The thromboxane B2 (TXB2) and serotonin concentrations were measured by ELISA. The flavonoids content was measured by ultraperformance liquid chromatography (UPLC). The antithrombotic activity of VLE was evaluated using various agonists in vitro. VLE strongly inhibited adenosine diphosphate (ADP)-induced platelet aggregation. In rats, VLE treatment (100 mg/kg) reduced ADP-stimulated platelet aggregation, without affecting tail bleeding and coagulation time. Moreover, VLE significantly suppressed TXB2 and serotonin secretion. UPLC analysis indicated that VLE contains quercetin, isorhamnetin, and rutin. Our results indicate that VLE possesses antiplatelet activity via the suppression of TXB2 and serotonin, without affecting bleeding. Further, we identified the flavonoids present in VLE. Thus, VLE may be a potential agent for the prevention of cardiovascular diseases.

The Anti-Cancer Effect of Polyphenols against Breast Cancer and Cancer Stem Cells: Molecular Mechanisms

The high incidence of breast cancer in developed and developing countries, and its correlation to cancer-related deaths, has prompted concerned scientists to discover novel alternatives to deal with this challenge. In this review, we will provide a brief overview of polyphenol structures and classifications, as well as on the carcinogenic process. The biology of breast cancer cells will also be discussed. The molecular mechanisms involved in the anti-cancer activities of numerous polyphenols, against a wide range of breast cancer cells, in vitro and in vivo, will be explained in detail. The interplay between autophagy and apoptosis in the anti-cancer activity of polyphenols will also be highlighted. In addition, the potential of polyphenols to target cancer stem cells (CSCs) via various mechanisms will be explained. Recently, the use of natural products as chemotherapeutics and chemopreventive drugs to overcome the side effects and resistance that arise from using chemical-based agents has garnered the attention of the scientific community. Polyphenol research is considered a promising field in the treatment and prevention of breast cancer.

Review: Health Effects of Cocoa Flavonoids

Flavonoids are phenolic substances widely found in fruits and vegetables. Many epidemiological studies associate the ingestion of flavonoids with a reduced risk of cardiovascular disease and certain types of cancer. These effects are due to the physiological activity of flavonoids in the reduction of oxidative stress, inhibiting low-density lipoproteins (LDL) oxidation and platelet aggregation, acting as vasodilators in blood vessels, inhibiting the adherence of monocytes to the vascular endothelium, promoting fibrinolysis, acting as immunomodulators and anti-inflammatory agents and as inhibitors in the different phases of tumour process. Cocoa is an important source of polyphenols, which comprise 12-18% of its total weight on dry basis; the major phenolic compounds are epicatechin, proanthocyanidins and cate-chin. The levels of flavonoids contained are higher than the ones founds in apples, onions or wine, foods known for their high amount of phenolic compounds. Cocoa and cocoa products are important sources of flavonoids in our diet. In the Dutch population chocolate contributes up to 20% of the total flavonoid intake in adults, and in children the percentage is even higher. The bioavailability of these compounds depends on other food constituents, and their interaction with the food matrix. This article reviews current evidence on the health effects of cocoa flavonoids in our diet. The compiled data supports the premise that the consumption of cocoa flavonoids is beneficial to human health.

Natural Virucidal Compounds in Foods

Many plant essential oils, extracts, and individual chemical components have been demonstrated to possess antiviral efficacy against enveloped and/or non-enveloped viruses. In general, plant antimicrobials exhibit greater antiviral efficacy against enveloped viruses than non-enveloped viruses (though not in all cases). There appear to be multiple mechanisms of antiviral action for plant antimicrobials; nevertheless, the majority of antimicrobials appear to act either directly on the virus itself (e.g., on the envelope or capsid) or during the early stages of virus replication following internalization of the virus into its host cell.

Cytoprotective Effect of Hydroalcoholic Extract of Pinus eldarica Bark against H2O2-Induced Oxidative Stress in Human Endothelial Cells

BACKGROUND

Pinus eldarica is a widely growing pine in Iran consisting of biologically active constituents with antioxidant properties. This study investigates the effect of hydroalcoholic extract of P. eldarica bark against oxidative damage induced by hydrogen peroxide (H2O2) in human umbilical vein endothelial cells (HUVECs).

METHODS

The total phenolic content of P. eldarica extract was determined using Folin-Ciocalteu method. The cytotoxicity of P. eldarica extract (25-1000 µg/ml) on HUVECs was assessed using 3-(4,5- Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) method. Cytoprotective effect of P. eldarica extract (25-500 µg/ml) on H2O2-induced oxidative stress was also evaluated by MTT assay. The intra- and extra-cellular hydroperoxides concentration and ferric reducing antioxidant power (FRAP) were measured in pretreated cells.

RESULTS

The total phenolic content of P. eldarica extract was estimated as 37.04±1.8% gallic acid equivalent. P. eldarica extract (25-1000 µg/ml) had no cytotoxic effect on HUVECs viability. The pretreatment of HUVECs with P. eldarica extract at the concentrations of 50-500 µg/ml significantly reduced the cytotoxicity of H2O2. P. eldarica extract decreased hydroperoxides concentration and increased FRAP value in intra-cellular fluid at the concentration range of 100-500 µg/ml and in extra-cellular fluid at the concentration range of 25-500 µg/ml.

CONCLUSIONS

This study revealed the antioxidant and cytoprotective effects of P. eldarica extract against H2O2-induced oxidative stress in HUVECs. Concerning the high content of phenolic compounds in P. eldarica, more research is needed to evaluate its clinical value in endothelial dysfunction and in other oxidative conditions.

Determination of some selected secondary metabolites and their invitro antioxidant activity in commercially available Ethiopian tea (Camellia sinensis)

Eight brands of tea (Camellia sinensis),which are cultivated and commercially available in Ethiopian market, were analyzed for estimation of their total secondary metabolites (polyphenols, flavonoids and tannins) content and free radical scavenging activity which is expressed on dry weight basis. In this present study, the total polyphenols, tannin and flavonoid contents were studied spectrophotometrically using Folin-Dennis, Folin-Dennis/protein precipitation and aluminium chloride methods respectively. The free radical scavenging activity was determined by using DPPH radical assay. Results of the analysis revealed that the total polyphenol content varied from 21.3 ± 0.24 to 31.6 ± 0.31 mg of gallic acid equivalent/g of dry matter. Total flavonoids content in the tea samples varied from 8.17 ± 0.68 to 23.2 ± 0.68 mg of catechin equivalent/g of dry weight and tannin content varied from 5.64 ± 0.39 7.45 ± 0.27 mg tannic acid equivalent/g of dry weight basis. The free radical scavenging activity among the tea brand samples ranged from 28.8 ± 1.86 to 80.0 ± 0.63 mg ascorbic acid equivalent/g and the half maximal inhibitory concentration (IC50%) values varied from 7.3 ± 1.35 to 64.0 ± 2.81 µg/mL of extract. The correlation between the antioxidant activity with total polyphenol content (R = 0.91325), with flavonoids (R = 0.80658) and with tannin (R = 0.73125) was calculated and maximum correlation value was found between polyphenol content and the free radical scavenging activity of the tea samples. The results in this study also revealed that green tea had the higher polyphenolic content and found to have the most promising antioxidant activity. This study further confirmed that Ethiopia tea is reach in phenolic compounds as compared to some overseas tea cultivars/varieties.