Protective Effects Of Polyphenols Research Articles

Harnessing the Power of Polyphenols: A New Frontier in Disease Prevention and Therapy.

There are a wide variety of phytochemicals collectively known as polyphenols. Their structural diversity results in a broad range of characteristics and biological effects. Polyphenols can be found in a variety of foods and drinks, including fruits, cereals, tea, and coffee. Studies both in vitro and in vivo, as well as clinical trials, have shown that they possess potent antioxidant activities, numerous therapeutic effects, and health advantages. Dietary polyphenols have demonstrated the potential to prevent many health problems, including obesity, atherosclerosis, high blood sugar, diabetes, hypertension, cancer, and neurological diseases. In this paper, the protective effects of polyphenols and the mechanisms behind them are investigated in detail, citing the most recent available literature. This review aims to provide a comprehensive overview of the current knowledge on the role of polyphenols in preventing and managing chronic diseases. The cited publications are derived from in vitro, in vivo, and human-based studies and clinical trials. A more complete understanding of these naturally occurring metabolites will pave the way for the development of novel polyphenol-rich diet and drug development programs. This, in turn, provides further evidence of their health benefits.

Challenging the safety and efficacy of topically applied chlorogenic acid, apigenin, kaempferol, and naringenin by HET-CAM, HPLC-TBARS-EVSC, and laser Doppler flowmetry.

The integumentary system, a vital organ, constitutes a multifaceted barrier against pathogens and environmental factors, crucial for maintaining homeostasis. Intrinsic and extrinsic factors can accelerate skin aging and compromise its homeostatic functions and solar rays, particularly ultraviolet (UV) radiation, pose a significant risk for skin cancer. Polyphenols are molecules that donate hydrogen or electrons, preventing the oxidation of substances, such as lipids, or the formation of inflammatory mediators by cyclooxygenase enzymes. This study explored the in vitro safety, by HET-CAM (hen's egg test on chorioallantoic membrane), and protective effects of polyphenols (chlorogenic acid, apigenin, kaempferol, and naringenin) against stratum corneum UV-induced lipid peroxidation using an innovative method, the HPLC-TBARS-EVSC (high-performance liquid chromatography-thiobarbituric acid reactive substances-ex vivo stratum corneum), and a stress test using methyl nicotinate and laser Doppler flowmetry to establish in vivo the samples' topical anti-inflammatory ability. An aqueous gel containing 0.1% w/w of each polyphenol was formulated using ammonium acryloyldimethyltaurate/VP copolymer. Through the utilization of the HET-CAM assay for in vitro safety assessment, chlorogenic acid, apigenin, kaempferol, and naringenin were classified as non-irritating active ingredients. This classification was based on their lack of adverse reactions within the vascularization of the chorioallantoic membrane. To assess the protective capabilities of four polyphenols against lipid peroxidation in the stratum corneum, the HPLC-TBARS-EVSC protocol was conducted. It was observed that only naringenin exhibited a significant reduction in epidermal lipoperoxidation, indicating superior anti-radical potential. Conversely, chlorogenic acid, apigenin, and kaempferol displayed a pro-oxidant profile under the specified test conditions. The laser Doppler flowmetry suggested the anti-inflammatory potential of naringenin, kaempferol, and chlorogenic acid, with naringenin showing superior efficacy involving all parameters quantified. Naringenin emerged as the only polyphenol capable of reducing the intensity of the inflammatory response induced by methyl nicotinate solution in the participants, compared to the blank gel and the untreated area. This comprehensive investigation underscores the diverse protective roles of polyphenols in skin health, emphasizing naringenin's notable anti-radical and anti-inflammatory properties.

Protective Effect of Polyphenols, Protein, Peptides, and Polysaccharides on Alcoholic Liver Disease: A Review of Research Status and Molecular Mechanisms.

Alcoholic liver disease (ALD) has emerged as an important public health problem in the world. The polyphenols, protein, peptides, and polysaccharides have attracted attention for prevention or treatment of ALD. Therefore, this paper reviews the pathogenesis of ALD, the relationship between polyphenols, peptides, polysaccharides, and ALD, and expounds the mechanism of gut microbiota on protecting ALD. It is mainly found that the hydroxyl group of polyphenols endows it with antioxidation to protect ALD. The ALD protection of bioactive peptides is related to amino acid composition. The ALD protection of polysaccharides is related to the primary structure. Meanwhile, polyphenols, protein, peptides, and polysaccharides prevent or treat ALD by antioxidation, anti-inflammatory, antiapoptosis, lipid metabolism, and gut microbiota regulation. This contribution provides updated information on polyphenols, protein, peptides, and polysaccharides in response to ALD, which will not only facilitate the development of novel bioactive components but also the future application of functional food raw materials will be promoted.

Protective effects of polyphenols against endocrine disrupting chemicals.

Endocrine disrupting chemicals (EDCs) are a heterogenous group of compounds dispersed throughout the environment that possess the ability to alter endocrine system function. While there are numerous routes of exposure to EDCs, the predominant source of many of these compounds is diet, largely due to their widespread use in food contact materials. In recent years, there has been a surge of research aimed at assessing exposure to EDCs, identifying their health implications, and developing approaches to minimize the risks they may entail. Due to their antioxidant and anti-inflammatory potential, polyphenols have been purported to confer protection against EDC-induced health detriments. This review discusses the evidence pertaining to dietary exposure to the two predominant EDCs, bisphenol A and phthalates, in the United States, their associations with diabetes, cancer, and cardiovascular disease outcomes, the potential for polyphenols to mitigate their disease-promoting effects, gaps in knowledge, and recommendations for future research.

UPLC-Q-TOF-MS/MS Analysis of Phenolic Compounds from the Fruit of Cephalostachyum fuchsianum Gamble and Their Antioxidant and Cytoprotective Activities.

Bamboo is a widely distributed graminaceous plant in China and is a potential source of bioactive substances. Incidentally, bamboo’s fruit is rich in phytochemicals such as polyphenols and flavonoids, which are significant to human health. In this study, we identified the phenolic compounds of the fruit and investigated the antioxidant activities of Cephalostachyum fuchsianum Gamble (CFG) fruit polyphenols with in vitro and in vivo tests for the first time. UPLC–Q–TOF–MS/MS analysis results showed that the fruit contained 43 phenolic compounds, including 7 hydroxybenzoic acids, 12 flavonoids, 7 coumarins, 10 hydroxycinnamic acids, 1 terpenoid, and 5 lignans. The TPC of SP extracts was higher than that of IBPs extracts in FP and FF. The SP extracts in FP showed better antioxidant activities in vitro compared to those in FF. In addition, polyphenols from CFG fruits protected against H2O2-induced oxidative damage in HepG2 cells, and the protective effect of polyphenols in FP was superior to that in FF. The analysis results showed that CFG fruit has great potential in exploiting natural chemical substances, which can provide valuable pieces of information for the further development and utilization of CFG.

Antioxidant Polyphenols of Antirhea borbonica Medicinal Plant and Caffeic Acid Reduce Cerebrovascular, Inflammatory and Metabolic Disorders Aggravated by High-Fat Diet-Induced Obesity in a Mouse Model of Stroke.

Metabolic disorders related to obesity and type 2 diabetes are associated with aggravated cerebrovascular damages during stroke. In particular, hyperglycemia alters redox and inflammatory status, leading to cerebral endothelial cell dysfunction, blood–brain barrier (BBB) disruption and brain homeostasis loss. Polyphenols constitute the most abundant dietary antioxidants and exert anti-inflammatory effects that may improve cerebrovascular complications in stroke. This study evaluated the effects of the characterized polyphenol-rich extract of Antirhea borbonica medicinal plant and its major constituent caffeic acid on a high-fat diet (HFD)-induced obesity mouse model during ischemic stroke, and murine bEnd3 cerebral endothelial cells in high glucose condition. In vivo, polyphenols administered by oral gavage for 12 weeks attenuated insulin resistance, hyperglycemia, hyperinsulinemia and dyslipidemia caused by HFD-induced obesity. Polyphenols limited brain infarct, hemorrhagic transformation and BBB disruption aggravated by obesity during stroke. Polyphenols exhibited anti-inflammatory and antioxidant properties by reducing IL-1β, IL-6, MCP-1, TNF-α and Nrf2 overproduction as well as total SOD activity elevation at the cerebral or peripheral levels in obese mice. In vitro, polyphenols decreased MMP-2 activity that correlated with MCP-1 secretion and ROS intracellular levels in hyperglycemic condition. Protective effects of polyphenols were linked to their bioavailability with evidence for circulating metabolites including caffeic acid, quercetin and hippuric acid. Altogether, these findings show that antioxidant polyphenols reduced cerebrovascular, inflammatory and metabolic disorders aggravated by obesity in a mouse model of stroke. It will be relevant to assess polyphenol-based strategies to improve the clinical consequences of stroke in the context of obesity and diabetes.

Protective Effects of Polyphenols against Ischemia/Reperfusion Injury.

Myocardial infarction (MI) is a leading cause of morbidity and mortality across the world. It manifests as an imbalance between blood demand and blood delivery in the myocardium, which leads to cardiac ischemia and myocardial necrosis. While it is not easy to identify the first pathogenic cause of MI, the consequences are characterized by ischemia, chronic inflammation, and tissue degeneration. A poor MI prognosis is associated with extensive cardiac remodeling. A loss of viable cardiomyocytes is replaced with fibrosis, which reduces heart contractility and heart function. Recent advances have given rise to the concept of natural polyphenols. These bioactive compounds have been studied for their pharmacological properties and have proven successful in the treatment of cardiovascular diseases. Studies have focused on their various bioactivities, such as their antioxidant and anti-inflammatory effects and free radical scavenging. In this review, we summarized the effects and benefits of polyphenols on the cardiovascular injury, particularly on the treatment of myocardial infarction in animal and human studies.

Banana condensed tannins scavenge glyphosate in aqueous solution through non-covalent interactions

The protective effects of polyphenols against glyphosate-induced toxicity in animals are generally considered to be associated with their antioxidant properties. Recently, some researchers put forward that the direct interactions of polyphenols with molecules may also play roles in their biological activities. However, there is little information about the direct interactions between polyphenols and glyphosate. Bananas are demonstrated to be rich in phenolic compounds (especially condensed tannins) at the unripe stage. To provide a possible new mechanism of protection by polyphenols against glyphosate intoxication, the direct interaction of banana condensed tannins (BCT) with glyphosate was characterized by different techniques for the first time. Our results showed that glyphosate could be effectively precipitated by BCT in aqueous solution, and the glyphosate scavenging ability of BCT (10.30–59.14%) significantly increased with the rising condensed tannin concentration (0.25–1.0 mg proanthocyanidin B2 equivalent/mL). Notably, the glyphosate scavenging ability of BCT was closely related to the electrostatic interactions, hydrogen-bond interactions and hydrophobic interactions between BCT and glyphosate. In addition, the interaction of glyphosate with BCT was further confirmed by characterizing the BCT-glyphosate coprecipitates using spectroscopic methods and morphological analysis. Therefore, the precipitation of glyphosate by BCT might reduce the toxicity of glyphosate through affecting its gastrointestinal absorption.

Effect of polyphenols from wild Chilean currants (Ribes spp.) on the activity of intracellular antioxidant enzymes in human gastric AGS cells

The protective effect of polyphenols from Chilean currants (Ribes spp.) in human epithelial gastric cells (AGS) against oxidative induced-stress has been recently reported. The aim of the present study was to assess the ability of polyphenol-enriched extracts (PEE) from three Chilean Ribes species to modify the activities of the intracellular antioxidant enzymes: catalase (CAT), glutathione peroxidase (GSH-Px), glutathione reductase (GSH-R) and superoxide dismutase (SOD) in AGS cells. The PEE of each species was fractionated using membrane chromatography to give an anthocyanin-enriched fraction (AF) and a copigment fraction (CF). A significant increase in the SOD activity was observed with a dose-response effect after an overnight incubation of AGS cells with the PEE, AF and CF from the selected species. The activity of CAT was enhanced by the CF of Ribes magellanicum and R. cucullatum, and by the AF of R. punctatum. For the GSH-R, a dose-response effect was observed in the extracts of R. magellanicum, while for the GSH-Px activity, only the AF of R. magellanicum and R. cucullatum had a significant increase. The studied samples were not able to increase the intracellular GSH content. Only the R. magellanicum samples raised the intracellular total antioxidant activity. These results suggested that the increase in the activity of the antioxidant response enzymes is associated with the cytoprotective effect of these native currants.

Dietary Polyphenols in the Prevention of Stroke.

Polyphenols have an important protective role against a number of diseases, such as atherosclerosis, brain dysfunction, stroke, cardiovascular diseases, and cancer. Cardiovascular diseases are the number one cause of death worldwide: more people die annually from cardiovascular diseases than from any other cause. The most important behavioural risk factors of heart disease and stroke are unhealthy diet, physical inactivity, tobacco use, and excess alcohol intake. The dietary consumption of polyphenols has shown to be inversely associated with morbidity and mortality by cardio- and cerebrovascular diseases. It is well-known that the protective effects of polyphenols in vivo depend on the grade how they are extracted from food and on their intestinal absorption, metabolism, and biological action with target tissues. The aim of this review was to summarise the relation between polyphenols of different plant sources and stroke in human intervention studies, animal models, and in vitro studies.

Human Intervention Study to Assess the Effects of Supplementation with Olive Leaf Extract on Peripheral Blood Mononuclear Cell Gene Expression.

Olive leaf extract (OLE) has been used for many years for its putative health benefits, but, to date, scientific evidence for the basis of these effects has been weak. Although recent literature has described a link between ailments such as cardiovascular disease, diabetes and cancer and a protective effect of polyphenols in the OLE, the mode of action is still unclear. Here, we describe a double-blinded placebo (PBO)-controlled trial, in which gene expression profiles of peripheral blood mononuclear cells from healthy male volunteers (n = 29) were analysed to identify genes that responded to OLE, following an eight-week intervention with 20 mL daily consumption of either OLE or PBO. Differences between groups were determined using an adjusted linear model. Subsequent analyses indicated downregulation of genes important in inflammatory pathways, lipid metabolism and cancer as a result of OLE consumption. Gene expression was verified by real-time PCR for three genes (EGR1, COX-2 and ID3). The results presented here suggest that OLE consumption may result in health benefits through influencing the expression of genes in inflammatory and metabolic pathways. Future studies with a larger study group, including male and female participants, looking into direct effects of OLE on lipid metabolism and inflammation are warranted.

Protective effect of polyphenols on presbycusis via oxidative/nitrosative stress suppression in rats

Age-related hearing loss (AHL) –presbycusis– is the number one neurodegenerative disorder and top communication deficit of our aged population. Experimental evidence suggests that mitochondrial dysfunction associated with reactive oxygen species (ROS) plays a central role in the aging process of cochlear cells. Dietary antioxidants, in particular polyphenols, have been found to be beneficial in protecting against the generation of ROS in various diseases associated with oxidative stress, such as cancer, neurodegenerative diseases and aging. ObjectivesThis study was designed to investigate the effects of polyphenols on AHL and to determine whether oxidative stress plays a role in the pathophysiology of AHL. MethodsSprague-Dawley rats (n=100) were divided into five groups according to their age (3, 6, 12, 18 and 24months old) and treated with 100mg/kg/day body weight of polyphenols dissolved in tap water for half of the life of the animal. Auditory steady-state responses (ASSR) threshold shifts were measured before sacrificing the rats. Then, cochleae were harvested to measure total superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities, reactive oxidative and nitrogen species levels, superoxide anions and nitrotyrosine levels. ResultsIncreased levels of ROS and RNS in cochlea observed with age decreases with polyphenol treatment. In addition, the activity of SOD and GPx enzymes in older rats recovered after the administration of polyphenols. Conclusion: The reduction in oxidative and nitrosative stress in the presence of polyphenols correlates with significant improvements in ASSR threshold shifts.

Protection of pancreatic β-cell function by dietary polyphenols

Diabetes mellitus is a complex metabolic disorder and is considered a fast-growing global health problem. Type 2 diabetes (T2D) represents the majority of total diabetes prevalence and β-cell dysfunction has been described as a crucial point for this disease development and progression. To date, all of the common anti-hyperglycaemic drugs used for diabetes management cause undesirable side effects or problems with long-term efficacy or safety and the development of alternative approaches for the prevention as well as for the treatment of T2D might be a valuable solution to meet this rising demand. In this regards, numerous epidemiological studies indicate that exposure to certain polyphenol compounds is associated with the prevention of chronic diseases, including diabetes. Here, we review growing evidence suggesting that polyphenols can modulate the activity of various molecular targets, which are known to control β-cell function, involved in the development and the progression of this diabetes. The protective effects of polyphenols on β-cell function is reported with a particular focus on the mechanism of action behind polyphenol putative bioactivity. Animal and in vitro studies selected in this review, reporting about both flavonoid and non-flavonoid compounds, highlight the direct action of polyphenols on pancreatic β-cells, stimulating insulin secretion through the activation of specific cellular targets and protecting these cells from damages mediated by oxidative stress and inflammation, both typically elevated in diabetes. Some of the reviewed studies describe polyphenol effects comparable to those exerted by many drugs commonly used in diabetes treatment, and, in some occasions, synergistic polyphenol-drug interactions. Finally, future studies need to be addressed to the effects of specific polyphenol human and microbial metabolites, which are still poorly studied, in order to better define the preventive and therapeutic approach to contrast β-cell failure and diabetes progression.

Protective effect Malus pumila Mill leaf polyphenols in reserpine-induced gastric ulcer in mice

The protective effect of polyphenols from Malus pumila leaf (MALP) on reserpine (10 mg/kg)-induced gastric ulcer in Kunming (KM) mice was investigated. Gastric juice secretion, pH of gastric juice, serum neuropeptides, including motilin (MOT), substance P (SP), vasoactive intestinal peptide (VIP), and somatostatin (SS) levels, as well as serum levels of inflammatory cytokines (TNF-α, IL-6, IL-12, and IFN-γ) were measured. Gastric occludin and p38MAPK phosphorylation was analyzed by RT-PCR or Western blotting. MALP reduced reserpine-induced gastric juice secretion and increased the pH of gastric juice. MALP increased the serum levels of VIP and SS and reduced MOT, SP, and inflammatory cytokines in serum. It also modulated the gastric expression of occludin and p38MAPK phosphorylation in mice. These results suggest that MALP showed a protective effect against reserpine-induced ulcer in mice by reducing gastric juice secretion, modulating serum neuropeptide levels, attenuating serum inflammatory cytokines, and regulating gastric levels of occludin and p38MAPK phosphorylation.

Protective effect of polyphenols from berries of Aronia melanocarpa against low exposure to cadmium-induced imbalance in the RANK/RANKL/OPG system in the bone tissue of rats

Protective effect of polyphenols from berries of Aronia melanocarpa against low exposure to cadmium-induced imbalance in the RANK/RANKL/OPG system in the bone tissue of rats

Protective effect of polyphenols from Aronia melanocarpa berries against cadmium-induced weakening of the femur biomechanical properties in rats

Protective effect of polyphenols from Aronia melanocarpa berries against cadmium-induced weakening of the femur biomechanical properties in rats

Increased Microparticle Production and Impaired Microvascular Endothelial Function in Aldosterone-Salt-Treated Rats: Protective Effects of Polyphenols

We aimed to characterize circulating microparticles in association with arterial stiffness, inflammation and endothelial dysfunction in aldosterone-salt-induced hypertension in rats and to investigate the preventive effects of red wine polyphenols. Uninephrectomized male Sprague-Dawley rats were treated with aldosterone-salt (1 µg.h−1), with or without administration of either red wine polyphenols, Provinols™ (20 mg.kg−1.day−1), or spironolactone (30 mg.kg−1.day−1) for 4 weeks. Microparticles, arterial stiffness, nitric oxide (NO) spin trapping, and mesenteric arterial function were measured. Aldosterone-salt rats showed increased microparticle levels, including those originating from platelets, endothelium and erythrocytes. Hypertension resulted in enhanced aortic stiffness accompanied by increased circulating and aortic NO levels and an upregulation of aortic inducible NO-synthase, NFκB, superoxide anions and nitrotyrosine. Flow-induced dilatation was reduced in mesenteric arteries. These effects were prevented by spironolactone. Provinols™ did not reduce arterial stiffness or systolic hypertension but had effects similar to those of spironolactone on endothelial function assessed by flow-mediated vasodilatation, microparticle generation, aortic NO levels and oxidative stress and apoptosis in the vessel wall. Neither the contractile response nor endothelium-dependent relaxation in mesenteric arteries differed between groups. The in vivo effects of Provinols™ were not mediated by mineralocorticoid receptors or changes in shear stress. In conclusion, vascular remodelling and endothelial dysfunction in aldosterone-salt-mediated hypertension are associated with increased circulating microparticles. Polyphenols prevent the enhanced release of microparticles, macrovascular inflammation and oxidative stress, and microvascular endothelial dysfunction independently of blood pressure, shear stress and mineralocorticoid receptor activation in a model of hyperaldosteronism.

Influence of plant polyphenols and medicinal plant extracts on antibiotic susceptibility of Escherichia coli

To investigate the influence of polyphenols and plant extracts on the susceptibility of Escherichia coli to antibiotics. Susceptibility of E. coli to antibiotics in the presence of extracts and polyphenols was estimated by the determination of the minimum inhibitory concentrations (MICs). To study gene expression, we used strains of E. coli carrying fusions between promoters of genes katG, sodA, iucC and structural β-galactosidase gene. Treatment with polyphenols and some plant extracts significantly decreased the antibacterial effects of antibiotics, to a larger extent, ciprofloxacin. The most remarkable protective effect was observed for the extracts of Chamerion (Epilobium) angustifolium, Filipendula vulgaris, Tanacetum vulgare and Serratula coronata. These extracts increased the MICs of ciprofloxacin by four and more times. In case of kanamycin, extracts of Artemisia austriaca and Artemisia pontica increased MICs by four and eight times, respectively. Polyphenol quercetin also caused protective effect against ciprofloxacin, increasing the MIC by four times. A positive correlation was found between protective effects of polyphenols and extracts and their antioxidant activity. Medicinal plant extracts and polyphenols may protect cells of E. coli against antibiotic toxicity. The results of this study may be used to enhance the efficiency of antibacterial therapies.

Protection by Polyphenols of Postprandial Human Plasma and Low-Density Lipoprotein Modification: The Stomach as a Bioreactor

Recent studies dramatically showed that the removal of circulating modified low-density lipoprotein (LDL) results in complete prevention of atherosclerosis. The gastrointestinal tract is constantly exposed to food, some of it containing oxidized compounds. Lipid oxidation in the stomach was demonstrated by ingesting heated red meat in rats. Red wine polyphenols added to the rats' meat diet prevented lipid peroxidation in the stomach and absorption of malondialdehyde (MDA) in rat plasma. In humans, postprandial plasma MDA levels rose by 3-fold after a meal of red meat cutlets. MDA derived from meat consumption caused postprandial plasma LDL modification in human. The levels of plasma MDA showed a 75% reduction by consumption of red wine polyphenols during the meat meal. Locating the main biological site of action of polyphenols in the stomach led to a revision in the understanding of how antioxidants work in vivo and may help to elucidate the mechanism involved in the protective effects of polyphenols in human health.

The protective effects of polyphenols from jujube peel (Ziziphus Jujube Mill) on isoproterenol-induced myocardial ischemia and aluminum-induced oxidative damage in rats

This study was aimed to evaluate the preventive effect of the polyphenols from Chinese jujube peel (Ziziphus jujube Mill. cv. Dongzao) against myocardial injury (MI) induced by isoproterenol (ISO) and biotoxicity of aluminum in rats. The free phenols from jujube peel (JPFP) and the bond phenols from jujube peel (JPBP) were administered to rats by gastric gavage. The results showed that prior administration of JPFP or JPBP remarkably inhibited increases in levels of malondialdehyde (MDA) and activities of Ca2+-ATPase and Mg2+-ATPase, reductions in activities of superoxide dismutase (SOD), glutathione peroxidase, creatine kinase, lactate dehydrogenase and Na+/K+-ATPase in the rats induced by ISO. The abnormal changes in morphology of heart muscle and in electrocardiograph induced by ISO treatment were also significantly prevented by the JPFP or JPBP. Treatment with aluminum chloride could cause a significant oxidative damage, including a significant increase in MDA level and decreases in glutathione-S- transferase and SOD activities in brain of the rats, the study showed that gavage with JPFP or JPBP could remarkably alleviate the toxic responses of the rats to aluminum chloride. In summary, our study showed that jujube phenolics can prevent ISO-induced myocardial injury and reduce aluminum toxicity in rats.