Regulation of Immune Function by Polyphenols

[Importance of nutrition for immune defense. The role of milk and its natural components]

The immune system is a complex and integrated system whose main function is to protect the body from external aggression by microorganisms, allergens, or toxic agents. Different studies show that maintaining optimal amounts of different nutrients in the body is essential to ensure the synthesis of different factors related to the immune system. Most interesting nutrients and bioactive compounds include: vitamins A, B6, B12, C, D, E, folic acid (B9) and biotin (B7); minerals such as zinc, iron, selenium, magnesium and copper; proteins (lactoferrin) and bioactive peptides; omega-3 fatty acids; and other nutrients and bioactive compounds such as fiber, polyphenols, carotenoids, probiotics, etc. Following a varied and balanced diet, including the servings recommended by food guides for each food group, is essential to achieve nutrient requirements. Food groups to which special attention should be paid are: fruits and vegetables (because of their high content in micronutrients and antioxidant compounds), fatty fish (because it contains omega-3 fatty acids), and dairy products (because this group contains a large amount of nutrients). In particular, milk-especially enriched milk-contains many of the nutrients mentioned above. And their daily consumption, within a balanced diet, can help significantly cover their nutrient reference values. Finally, it is important to consider enriched milks as a good dietary alternative to increase the intake of some important nutrients for the proper functioning of the immune system, most especially some of them such as vitamin D, since a large percentage of the population have nutritional deficiencies.

Advances in metabolic engineering of Corynebacterium glutamicum to produce high-value active ingredients for food, feed, human health, and well-being

The soil microbe Corynebacterium glutamicum is a leading workhorse in industrial biotechnology and has become famous for its power to synthetise amino acids and a range of bulk chemicals at high titre and yield. The product portfolio of the microbe is continuously expanding. Moreover, metabolically engineered strains of C. glutamicum produce more than 30 high value active ingredients, including signature molecules of raspberry, savoury, and orange flavours, sun blockers, anti-ageing sugars, and polymers for regenerative medicine. Herein, we highlight recent advances in engineering of the microbe into novel cell factories that overproduce these precious molecules from pioneering proofs-of-concept up to industrial productivity.

Nutraceuticals in Viral Infections: An Overview of the Immunomodulating Properties

Nutraceuticals, including vitamin D, vitamin A, zinc, lactoferrin, polyphenols coenzyme Q, magnesium, and selenium, are implicated in the modulation of the complex molecular pathways involved in the immune response against viral pathogens. A common element of the activity of nutraceuticals is their ability to enhance the innate immune response against pathogens by acting on the major cellular subsets and inducing the release of pro-inflammatory cytokines and antimicrobial peptides. In some cases, this action is accompanied by a direct antimicrobial effect, as evidenced in the specific case of lactoferrin. Furthermore, nutraceuticals act through complex molecular mechanisms to minimize the damage caused by the activation of the immune system against pathogens, reducing the oxidative damage, influencing the antigen presentation, enhancing the differentiation and proliferation of regulatory T cells, driving the differentiation of lymphocyte subsets, and modulating the production of pro-inflammatory cytokines. In this paper, we review the main molecular mechanisms responsible for the immunomodulatory function of nutraceuticals, focusing on the most relevant aspects for the prevention and treatment of viral infections.

Antifungal Combination of Ethyl Acetate Extract of Poincianella pluviosa (DC.) L. P. Queiros Stem Bark With Amphotericin B in Cryptococcus neoformans

Cryptococcus neoformans is the leading cause of cryptococcosis, an invasive and potentially fatal infectious disease. Therapeutic failures are due to the increase in antifungal resistance, the adverse effects of drugs, and the unavailability of therapeutic regimens in low-income countries, which limit the treatment of cryptococcosis, increasing the morbidity and mortality associated with these infections. Thus, new antifungal drugs and innovative strategies for the cryptococcosis treatment are urgently needed. The aim of the present study was to evaluate the effect of ethyl acetate fraction (EAF) of Poincianella pluviosa stem bark on planktonic and biofilm mode of growth of C. neoformans. Furthermore, the interaction between the EAF and amphotericin B (AmB) was evaluated in vitro and in Galleria mellonella infection model. Minimal inhibitory concentrations (MICs) of EAF ranged from 125.0 to >1,000.0 μg/ml and >1,000.0 μg/ml for planktonic and sessile cells, respectively. The combination between EAF and AmB exhibited a synergistic fungicidal activity toward C. neoformans, with a fractional inhibitory concentration index (FICI) ranging from 0.03 to 0.06 and 0.08 to 0.28 for planktonic and sessile cells, respectively. Microscopy analyses of planktonic C. neoformans cells treated with EAF, alone or combined with AmB, revealed morphological and ultrastructural alterations, including loss of integrity of the cell wall and cell membrane detachment, suggesting leakage of intracellular content, reduction of capsule size, and presence of vacuoles. Moreover, EAF alone or combined with AmB prolonged the survival rate of C. neoformans-infected G. mellonella larvae. These findings indicate that P. pluviosa may be an important source of new compounds that can be used as a fungus-specific adjuvant for the treatment of cryptococcosis.

Western Dietary Pattern Antioxidant Intakes and Oxidative Stress: Importance During the SARS-CoV-2/COVID-19 Pandemic

The importance of balanced dietary habits, which include appropriate amounts of antioxidants to maintain the immune system, has become increasingly relevant during the current SARS-CoV-2/COVID-19 pandemic, because viral infections are characterized by high oxidative stress. Furthermore, the measures taken by governments to control the pandemic have led to increased anxiety, stress, and depression, which affect physical and mental health, all of which are influenced by nutritional status, diet, and lifestyle. The Mediterranean diet (MD), Atlantic diet (AD), and the Dietary Guidelines for Americans all provide the essential vitamins, minerals, and phenolic compounds needed to activate enzymatic and nonenzymatic antioxidant responses. However, viral pandemics such as the current COVID-19 crisis entail high oxidative damage caused by both the infection and the resultant social stresses within populations, which increases the probability and severity of infection. Balanced dietary patterns such as the MD and the AD are characterized by the consumption of fruit, vegetables, legumes, olive oil, and whole grains with low intakes of processed foods and red meat. For a healthy lifestyle in young adults, the MD in particular provides the required amount of antioxidants per day for vitamins D (0.3-3.8 μg), E (17.0 mg), C (137.2-269.8 mg), A (1273.3 μg), B-12 (1.5-2.0 μg), and folate (455.1-561.3 μg), the minerals Se (120.0 μg), Zn (11.0 mg), Fe (15.0-18.8 mg), and Mn (5.2-12.5 mg), and polyphenols (1171.00 mg) needed to maintain an active immune response. However, all of these diets are deficient in the recommended amount of vitamin D (20 μg/d). Therefore, vulnerable populations such as elders and obese individuals could benefit from antioxidant supplementation to improve their antioxidant response. Although evidence remains scarce, there is some indication that a healthy diet, along with supplemental antioxidant intake, is beneficial to COVID-19 patients.

Ingestion of Okinawa Island Vegetables Increases IgA Levels and Prevents the Spread of Influenza RNA Viruses

Background: It has been hypothesized that flavonoid ingestion stimulates immunity, promotes health, and prevents human illness. The aim of this analysis was to evaluate the association of the levels of immunoglobulin A (IgA) with the prevention of influenza infections and with the polyphenols contained in Okinawan vegetables. Methods: IgA, immunoglobulin G (IgG), immunoglobulin M (IgM), and soluble interleukin-2 receptor (sIL-2R) levels were measured in 44 outpatients who regularly ingested vegetables grown on Okinawa Island (200–300 g/day for ≥ 300 days/year) with no history of influenza infection and in 73 patients who ingested the vegetables irregularly or not at all with a history of influenza infection. Results: The patients who regularly ate Okinawan vegetables had higher IgA, IgG, and IgM levels than those who did not. On the other hand, patients who did not consume Okinawan vegetables and had influenza had lower IgA, IgG, and IgM levels. In addition, the IgA and IgG levels showed significant positive correlations with the sIL-2R levels in both groups. Conclusions: It may be beneficial to eat vegetables abundant in polyphenols every day. Secretory IgA antibodies are an important part of the immune defense against viral diseases. People who ingest Okinawan vegetables have high IgA levels and might be more likely to develop immunity against influenza RNA viruses.

Encapsulated Food Products as a Strategy to Strengthen Immunity Against COVID-19

In December 2019, the severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2)-a novel coronavirus was identified which was quickly distributed to more than 100 countries around the world. There are currently no approved treatments available but only a few preventive measures are available. Among them, maintaining strong immunity through the intake of functional foods is a sustainable solution to resist the virus attack. For this, bioactive compounds (BACs) are delivered safely inside the body through encapsulated food items. Encapsulated food products have benefits such as high stability and bioavailability, sustained release of functional compounds; inhibit the undesired interaction, and high antimicrobial and antioxidant activity. Several BACs such as ω-3 fatty acid, curcumin, vitamins, essential oils, antimicrobials, and probiotic bacteria can be encapsulated which exhibit immunological activity through different mechanisms. These encapsulated compounds can be recommended for use by various researchers, scientists, and industrial peoples to develop functional foods that can improve immunity to withstand the coronavirus disease 2019 (COVID-19) outbreak in the future. Encapsulated BACs, upon incorporation into food, offer increased functionality and facilitate their potential use as an immunity booster. This review paper aims to target various encapsulated food products and their role in improving the immunity system. The bioactive components like antioxidants, minerals, vitamins, polyphenols, omega (ω)-3 fatty acids, lycopene, probiotics, etc. which boost the immunity and may be a potential measure to prevent COVID-19 outbreak were comprehensively discussed. This article also highlights the potential mechanisms; a BAC undergoes, to improve the immune system.

Exploring the role of polyphenols in rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic, inflammatory and autoimmune disorder which is mainly characterized by inflammation in joints, bone erosions and cartilaginous destruction that leads to joint dysfunction, deformation, and/or permanent functional impairment. The prevalence of RA is increasing, incurring a considerable burden on healthcare systems globally. The exact etiology of RA is unknown, with various pathways implicated in its pathophysiology. Non-steroidal anti-inflammatory drugs (NSAIDs) including celecoxib, diclofenac and ibuprofen, disease-modifying anti-rheumatic drugs (DMARD) including azathioprine, methotrexate and cyclosporine, biological agents including anakinra, infliximab, and rituximab and immunosuppressants are used for symptomatic relief in patients with RA, but these medications have severe adverse effects such as gastric ulcers, hypertension, hepatotoxicity and renal abnormalities which restrict their use in the treatment of RA; new RA treatments with minimal side-effects are urgently required. There is accumulating evidence that dietary polyphenols may show therapeutic efficacy in RA through their antioxidant, anti-inflammatory, apoptotic, and immunosuppressant activities and modulation of the tumor necrosis factor-α (TNF-α), interleukin (IL)-6, mitogen-activated protein kinase (MAPK), IL-1β, c-Jun N-terminal kinase (JNK), and nuclear factor κ light-chain-enhancer of activated B cell (NF-κB) pathways. While resveratrol, genistein, carnosol, epigallocatechin gallate, curcumin, kaempferol, and hydroxytyrosol have also been studied for the treatment of RA, the majority of data are derived from animal models. Here, we review the various pathways involved in the development of RA and the preclinical and clinical data supporting polyphenols as potential therapeutic agents in RA patients. Our review highlights that high-quality clinical studies are required to decisively establish the anti-rheumatic efficacy of polyphenolic compounds.

Nutritional considerations to counteract gastrointestinal permeability during exertional heat stress

Intestinal barrier integrity and function are compromised during exertional heat stress (EHS) potentially leading to consequences that range from minor gastrointestinal (GI) disturbances to fatal outcomes in exertional heat stroke or septic shock. This mini-review provides a concise discussion of nutritional interventions that may protect against intestinal permeability during EHS and suggests physiological mechanisms responsible for this protection. Although diverse nutritional interventions have been suggested to be protective against EHS-induced GI permeability, the ingestion of certain amino acids, carbohydrates, and fluid per se is potentially effective strategy, whereas evidence for various polyphenols and pre/probiotics is developing. Plausible physiological mechanisms of protection include increased blood flow, epithelial cell proliferation, upregulation of intracellular heat shock proteins, modulation of inflammatory signaling, alteration of the GI microbiota, and increased expression of tight junction (TJ) proteins. Further clinical research is needed to propose specific nutritional candidates and recommendations for their application to prevent intestinal barrier disruption and elucidate mechanisms during EHS.

Herbal immune-boosters: Substantial warriors of pandemic Covid-19 battle

Current scenario depicts that world has been clenched by COVID-19 pandemic. Inevitably, public health and safety measures could be undertaken in order to dwindle the infection threat and mortality. Moreover, to overcome the global menace and drawing out world from moribund stage, there is an exigency for social distancing and quarantines. Since December, 2019, coronavirus, SARS-CoV-2 (COVID-19) have came into existence and up till now world is still in the state of shock.At this point of time, COVID-19 has entered perilous phase, creating havoc among individuals, and this has been directly implied due to enhanced globalisation and ability of the virus to acclimatize at all conditions. The unabated transmission is due to lack of drugs, vaccines and therapeutics against this viral outbreak. But research is still underway to formulate the vaccines or drugs by this means, as scientific communities are continuously working to unravel the pharmacologically active compounds that might offer a new insight for curbing infections and pandemics. Therefore, the topical COVID-19 situation highlights an immediate need for effective therapeutics against SARS-CoV-2. Towards this effort, the present review discusses the vital concepts related to COVID-19, in terms of its origin, transmission, clinical aspects and diagnosis. However, here, we have formulated the novel concept hitherto, ancient means of traditional medicines or herbal plants to beat this pandemic.

The suppression of IL-17 production from T cells by gallate-type procyanidin is mediated by selectively inhibiting cytokine production from dendritic cells

Abnormal T helper 17 (Th17) responses promote inflammation and cause inflammatory diseases. Natural components that modulate Th17 functions can be effective for the amelioration of inflammatory diseases. Procyanidin B2 3,3''-di-O-gallate (PCB2DG) contained in grape seeds markedly suppressed interleukin (IL)-17 production from spleen cells but not CD4+ T cells. The aim of this study was to elucidate the mechanisms by which PCB2DG suppresses IL-17. Our results showed that PCB2DG suppressed the production of IL-17, tumor necrosis factor (TNF)-α, IL-1β, and IL-6 with the suppression of transcription factors expression. In addition, we revealed that TNF-α and IL-1β were required to induce IL-17 production in this experimental condition, and PCB2DG suppressed these cytokines from dendritic cells (DCs). Furthermore, CD4-DC co-culture experiments showed that the production of IL-17, TNF-α, and IL-1β was markedly inhibited in co-cultures of PCB2DG-pretreated CD4+ T cells and DCs. These results suggested that PCB2DG first modulated TNF-α production by CD4+ T cells and then suppressed IL-1β secretion from DCs, resulting in decreased IL-17 production. Thus, PCB2DG can control the cytokine network associated with Th17 cells, providing a novel mechanism underlying the immunosuppressive effects of polyphenols.

Potential Application of Plant-Based Functional Foods in the Development of Immune Boosters

Immune dysfunction, which is responsible for the development of human diseases including cancer, is caused by a variety of factors. Therefore, regulation of the factors influencing the immune response is a potentially effective strategy to counter diseases. Presently, several immune adjuvants are used in clinical practice to enhance the immune response and host defense ability; however, synthetic drugs can exert negative side effects. Thus, the search for natural products of plant origin as new leads for the development of potent and safe immune boosters is gaining considerable research interest. Plant-based functional foods have been shown to exert several immunomodulatory effects in humans; therefore, the application of new agents to enhance immunological and specific host defenses is a promising approach. In this comprehensive review, we have provided an up-to-date report on the use as well as the known and potential mechanisms of bioactive compounds obtained from plant-based functional foods as natural immune boosters. Plant-based bioactive compounds promote immunity through multiple mechanisms, including influencing the immune organs, cellular immunity, humoral immunity, nonspecific immunity, and immune-related signal transduction pathways. Enhancement of the immune response in a natural manner represents an excellent prospect for disease prevention and treatment and is worthy of further research and development using approaches of modern science and technology.

Green Design of Novel Starch-Based Packaging Materials Sustaining Human and Environmental Health

A critical overview of current approaches to the development of starch-containing packaging, integrating the principles of green chemistry (GC), green technology (GT) and green nanotechnology (GN) with those of green packaging (GP) to produce materials important for both us and the planet is given. First, as a relationship between GP and GC, the benefits of natural bioactive compounds are analyzed and the state-of-the-art is updated in terms of the starch packaging incorporating green chemicals that normally help us to maintain health, are environmentally friendly and are obtained via GC. Newer approaches are identified, such as the incorporation of vitamins or minerals into films and coatings. Second, the relationship between GP and GT is assessed by analyzing the influence on starch films of green physical treatments such as UV, electron beam or gamma irradiation, and plasma; emerging research areas are proposed, such as the use of cold atmospheric plasma for the production of films. Thirdly, the approaches on how GN can be used successfully to improve the mechanical properties and bioactivity of packaging are summarized; current trends are identified, such as a green synthesis of bionanocomposites containing phytosynthesized metal nanoparticles. Last but not least, bioinspiration ideas for the design of the future green packaging containing starch are presented.

Epigallocatechin Gallate Can Protect Mice From Acute Stress Induced by LPS While Stabilizing Gut Microbes and Serum Metabolites Levels

Epigallocatechin gallate (EGCG) has potent biological activity as well as strong antioxidant and anti-inflammatory effects. This study aims to explore the protective effect of EGCG on LPS-induced acute injury. We randomly divided 18 mice into three groups: CON, LPS, and EGCG-LPS. We gave the EGCG-LPS group gavage treatment with EGCG on day 8–15 and an intraperitoneal injection of LPS on day 16 to induce acute injury. The results showed that, compared with the LPS group, the bodyweight of the mice in the EGCG-LPS group increased significantly and effectively inhibited the morphological damage of the jejunum and liver. We measured liver tissue and found that the EGCG gavage treatment significantly inhibited the pro-inflammatory factors (TNF-α, IL-1β, IL-6, MCP-1, MIP-2, IFN-γ) and oxidation indicators (MPO, NO, ALT, and AST) levels increase. The microbiological results showed that the EGCG gavage treatment reshaped the disturbance done to the intestinal microbial community in the mice by LPS, reversed the changes in the abundance ratio of Firmicutes/Bacteroidetes, and significantly reduced the abundance of Enterobacteriales. Finally, the serum metabolomics results showed that, when compared with the LPS group, the gavage treatment of EGCG significantly increased the concentration of sphingomyelin (d17:1/17:0), sphingomyelin (d16:1/20:0), and significantly reduced the content of trans-Hexadec-2-enoyl carnitine, and so on. Therefore, we believe that EGCG can protect mice from acute stress induced by LPS while stabilizing gut microbes in general, improving the metabolism of sphingolipids, and inhibiting the content of harmful metabolites.

Characterization of a lignin from Crataeva tapia leaves and potential applications in medicinal and cosmetic formulations

Lignins are phenolic macromolecules that have several applications. In this work, we examine some biological activities of a lignin-like macromolecule isolated from the Crataeva tapia leaves, not yet studied to evaluate its potential applications in medicinal and cosmetic formulations. Lignin was obtained by alkaline delignification and its physical-chemical characterization was made by means of FT-IR, UV-Vis, NMR spectroscopy, elementary analysis, molecular mass determination and thermal analysis. Lignin is of the GSH type, with levels of hydrogen (5.10%), oxygen (27.18%), carbon (67.60%), nitrogen (0.12%) and phenolic content of 189.6 ± 9.6 mg GAE/g. In addition, it is a thermally stable macromolecule with low antioxidant activity. Cytotoxicity and cytokine production were assessed by flow cytometry. The photoprotective activity was evaluated by adding different concentrations of lignin to a commercial cream. Lignin was not cytotoxic, it stimulated the production of TNF-α, IL-6 and IL-10 and did not promote a significant change in nitric oxide levels. In addition, this macromolecule was able to promote increased absorption of ultraviolet light from a commercial cream. These results reinforce the ethnopharmacological use of C. tapia leaves and suggest the need for further studies to determine the potential medicinal and cosmetic applications (sunscreen) of lignin from C. tapia leaves.

Pathology, Risk Factors, and Oxidative Damage Related to Type 2 Diabetes-Mediated Alzheimer's Disease and the Rescuing Effects of the Potent Antioxidant Anthocyanin

The pathology and neurodegeneration in type 2 diabetes- (T2D-) mediated Alzheimer's disease (AD) have been reported in several studies. Despite the lack of information regarding the basic underlying mechanisms involved in the development of T2D-mediated AD, some common features of the two conditions have been reported, such as brain atrophy, reduced cerebral glucose metabolism, and insulin resistance. T2D phenotypes such as glucose dyshomeostasis, insulin resistance, impaired insulin signaling, and systemic inflammatory cytokines have been shown to be involved in the progression of AD pathology by increasing amyloid-beta accumulation, tau hyperphosphorylation, and overall neuroinflammation. Similarly, oxidative stress, mitochondrial dysfunction, and the generation of advanced glycation end products (AGEs) and their receptor (RAGE) as a result of chronic hyperglycemia may serve as critical links between diabetes and AD. The natural dietary polyflavonoid anthocyanin enhances insulin sensitivity, attenuates insulin resistance at the level of the target tissues, inhibits free fatty acid oxidation, and abrogates the release of peripheral inflammatory cytokines in obese (prediabetic) individuals, which are responsible for insulin resistance, systemic hyperglycemia, systemic inflammation, brain metabolism dyshomeostasis, amyloid-beta accumulation, and neuroinflammatory responses. In this review, we have shown that obesity may induce T2D-mediated AD and assessed the recent therapeutic advances, especially the use of anthocyanin, against T2D-mediated AD pathology. Taken together, the findings of current studies may help elucidate a new approach for the prevention and treatment of T2D-mediated AD by using the polyflavonoid anthocyanin.

Health-Promoting Phytonutrients Are Higher in Grass-Fed Meat and Milk

While commission reports and nutritional guidelines raise concerns about the effects of consuming red meat on human health, the impacts of how livestock are raised and finished on consumer health are generally ignored. Meat and milk, irrespective of rearing practices, provide many essential nutrients including bioavailable protein, zinc, iron, selenium, calcium, and/or B12. Emerging data indicate that when livestock are eating a diverse array of plants on pasture, additional health-promoting phytonutrients—terpenoids, phenols, carotenoids, and anti-oxidants—become concentrated in their meat and milk. Several phytochemicals found in grass-fed meat and milk are in quantities comparable to those found in plant foods known to have anti-inflammatory, anti-carcinogenic, and cardioprotective effects. As meat and milk are often not considered as sources of phytochemicals, their presence has remained largely underappreciated in discussions of nutritional differences between feedlot-fed (grain-fed) and pasture-finished (grass-fed) meat and dairy, which have predominantly centered around the ω-3 fatty acids and conjugated linoleic acid. Grazing livestock on plant-species diverse pastures concentrates a wider variety and higher amounts of phytochemicals in meat and milk compared to grazing monoculture pastures, while phytochemicals are further reduced or absent in meat and milk of grain-fed animals. The co-evolution of plants and herbivores has led to plants/crops being more productive when grazed in accordance with agroecological principles. The increased phytochemical richness of productive vegetation has potential to improve the health of animals and upscale these nutrients to also benefit human health. Several studies have found increased anti-oxidant activity in meat and milk of grass-fed vs. grain-fed animals. Only a handful of studies have investigated the effects of grass-fed meat and dairy consumption on human health and show potential for anti-inflammatory effects and improved lipoprotein profiles. However, current knowledge does not allow for direct linking of livestock production practices to human health. Future research should systematically assess linkages between the phytochemical richness of livestock diets, the nutrient density of animal foods, and subsequent effects on human metabolic health. This is important given current societal concerns about red meat consumption and human health. Addressing this research gap will require greater collaborative efforts from the fields of agriculture and medicine.

Bioremediation effect of pomegranate peel on subchronic mercury immunotoxicity on African catfish (Clarias gariepinus)

The primary aim of the present study is to evaluate the highest concentrations of heavy metals (HMs) in Nile catfish (Clarias gariepinus, C. gariepinus) and water samples, as well as to investigate the efficiency of pomegranate peels (PPs) (supplemented either through water or diet) in enhancing fish immunity and counteracting the toxicity of high concentrations of HMs. Water and C. gariepinus samples were collected from two private fish farms in Al Sharkia Governorate. Mercury (Hg) showed the highest concentration (0.13 ppm). The adsorption capacity of PP was evaluated by testing different concentrations, 0.3, 0.6, 0.9, 1.2, and 1.5 g L^-1, wherein 1.5 g L^-1 revealed the highest Hg adsorption efficiency. The results indicated that Hg concentration was decreased with increased PP concentration until 72 h. In a trial that lasted for 60 days, 240 C. gariepinus (75.12 ± 3.12 g) were randomly divided into eight equal groups with three replicates per group. The first group (CT) served as the negative control (fish fed on a basal diet). The second group (PPW) was fed on a basal diet and supplemented with 0.3 g L^-1 of PP via water. The third (PPD1) and fourth (PPD2) groups received basal diets enriched with 1 and 2 g PP powder/kg diet. respectively. The fifth group (Hg) served as the positive control that was fed on a basal diet and exposed to 0.13 ppm of Hg. The sixth (Hg + PPW), seventh (Hg + PPD1), and eighth (Hg + PPD2) groups were exposed to 0.13 ppm of Hg and received the same type of treatment as in second, third, and fourth groups. Hg exposure significantly elevated aspartate aminotransferase (AST), alanine aminotransferase (ALT), urea, and creatinine levels, as well as oxidative stress biomarkers, including reduced glutathione (GSH) and malondialdehyde (MDA). Pomegranate supplementation through diet elevated the levels of red blood cells (RBCs), hemoglobin (Hb), packed cell volume (PCV), lysozyme, and anti-protease activity. Moreover, PP supplementation through water revealed minimum urea and creatinine levels, and the highest nitric oxide level. Moreover, Hg residue level in fish muscles noticeably decreased in the PP-treated groups. These results demonstrated the efficiency of PP supplementation (either through water or diet) in enhancing fish immunity and counteracting subchronic Hg toxicity.

Relationships between Plant Defense Inducer Activities and Molecular Structure of Gallomolecules

Plant defense inducers (PDIs) are booming and attractive protection agents designed to immunostimulate the plant to reduce subsequent pathogen colonization. The structure-PDI activity relationships of four flavan-3-ols: Epicatechin (EC), Epigallocatechin (EGC), Epicatechin gallate (ECG), Epigallocatechin gallate (EGCG) and Gallotannic acid (GTA) were investigated in both whole plant and suspension cell systems. ECG, EGCG, and GTA displayed elicitor activities. Their infiltration into tobacco leaves induced hypersensitive reaction-like lesions with topical scopoletin and PR-target transcript accumulations. On the contrary, EC and EGC infiltrations fail to trigger the biochemical changes in tobacco tissues. The tobacco BY-2 cells challenged with ECG, EGCG, or GTA led to alkalinization of the BY-2 extracellular medium while EC and EGC did not trigger any pH variation. This work provides evidence that the esterified gallate pattern is as an essential flavonoid entity to induce plant defense reactions in tobacco. The phytoprotective properties of the esterified gallate-free EC and the esterified gallate-rich GTA were evaluated on the tobacco/Phytophthora parasitica var. nicotianae (Ppn) pathosystem. Tobacco treatment with EC did not induce significant protection against Ppn compared to GTA which shows antimicrobial properties on Ppn and decreases the infection on GTA-infiltrated and -sprayed wild-type leaves. GTA protection was impaired in the transgenic NahG tobacco plants, suggesting that protection was mediated by salicylic acid.

Present Status and Future Trends of Natural-Derived Compounds Targeting T Helper (Th) 17 and Microsomal Prostaglandin E Synthase-1 (mPGES-1) as Alternative Therapies for Autoimmune and Inflammatory-Based Diseases

Several natural-based compounds and products are reported to possess anti-inflammatory and immunomodulatory activity both in vitro and in vivo. The primary target for these activities is the inhibition of eicosanoid-generating enzymes, including phospholipase A2, cyclooxygenases (COXs), and lipoxygenases, leading to reduced prostanoids and leukotrienes. Other mechanisms include modulation of protein kinases and activation of transcriptases. However, only a limited number of studies and reviews highlight the potential modulation of the coupling enzymatic pathway COX-2/mPGES-1 and Th17/Treg circulating cells. Here, we provide a brief overview of natural products/compounds, currently included in the Italian list of botanicals and the BELFRIT, in different fields of interest such as inflammation and immunity. In this context, we focus our opinion on novel therapeutic targets such as COX-2/mPGES-1 coupling enzymes and Th17/Treg circulating repertoire. This paper is dedicated to the scientific career of Professor Nicola Mascolo for his profound dedication to the study of natural compounds.

Myricetin: A review of the most recent research

Myricetin(MYR) is a flavonoid compound widely found in many natural plants including bayberry. So far, MYR has been proven to have multiple biological functions and it is a natural compound with promising research and development prospects. This review comprehensively retrieved and collected the latest pharmacological abstracts on MYR, and discussed the potential molecular mechanisms of its effects. The results of our review indicated that MYR has a therapeutic effect on many diseases, including tumors of different types, inflammatory diseases, atherosclerosis, thrombosis, cerebral ischemia, diabetes, Alzheimer's disease and pathogenic microbial infections. Furthermore, it regulates the expression of Hippo, MAPK, GSK-3β, PI3K/AKT/mTOR, STAT3, TLR, IκB/NF-κB, Nrf2/HO-1, ACE, eNOS / NO, AChE and BrdU/NeuN. MYR also enhances the immunomodulatory functions, suppresses cytokine storms, improves cardiac dysfunction, possesses an antiviral potential, can be used as an adjuvant treatment against cancer, cardiovascular injury and nervous system diseases, and it may be a potential drug against COVID-19 and other viral infections. Generally, this article provides a theoretical basis for the clinical application of MYR and a reference for its further use.

Flavonoids as Multi-Target Compounds: A Special Emphasis on their Potential as Chemo-adjuvants in Cancer Therapy

Flavonoids are low molecular weight, polyphenolic phytochemicals, obtained from secondary metabolism of various plant compounds. They have a spectrum of pharmacological efficacies, including potential anticancer efficacy. Natural flavonoids are present in fruits, vegetables, grains, bark, roots, stems, flowers, tea and wine. Flavonoids can attenuate or inhibit the initiation, promotion and progression of cancer by modulating various enzymes and receptors in diverse pathways that involve cellular proliferation, differentiation, apoptosis, inflammation, angiogenesis and metastasis. Furthermore, in vitro, flavonoids have been shown to reverse multidrug resistance when used as chemo-adjuvants. Flavonoids (both natural and synthetic analogues) interact with several oncogenic targets through dependent and independent mechanisms to mediate their anticancer efficacy in different types of cancer cells.

8-Epi-xanthatin induces the apoptosis of DU145 prostate carcinoma cells through signal transducer and activator of transcription 3 inhibition and reactive oxygen species generation

Signal transducer and activator of transcription 3 (STAT3) is aberrantly activated in many human cancers. We tried to find STAT3 inhibitors from natural sources and found that Xanthium fruit extracts decreased phosphorylation of STAT3-Y705. 8-Epi-xanthatin (EXT) was isolated from the extracts. When DU145 cancer cells were treated with EXT, p-STAT3-Y705 was decreased with an IC₅₀ of 3.2 μM. EXT decreased the expression of STAT3 target genes, such as cyclin A, cyclin D1, and BCL-2, and induced PARP cleavage, indicating apoptotic cell death. Downregulation of EXT-induced p-STAT3-Y705 was rescued by pretreating DU145 cells with antioxidants, such as N-acetyl-L-cysteine (NAC), indicating that reactive oxygen species (ROS) were involved in the EXT-induced inhibition of STAT3 activation. Furthermore, we proved the association of EXT with STAT3 protein by using a drug affinity responsive target stability (DARTS) assay and a cellular thermal shift assay (CETSA). EXT inhibited proliferation of DU145 cells with a GI₅₀ of 6 μM and reduced tumor growth in mice xenografted with DU145 cells. Immunoblotting showed that phosphorylation of STAT3-Y705 was lower in EXT-treated tumor tissue than in control tissues. Collectively, we found that EXT binds to, and inhibits, STAT3 activation and could be a lead compound for anticancer therapy.

Dietary inclusion of chestnut (Castanea sativa) polyphenols to Nile tilapia reared in biofloc technology: Impacts on growth, immunity, and disease resistance against Streptococcus agalactiae

A feeding trial was carried out to examine the effects of adding chestnut (Castanea sativa) polyphenols (CSP) on the growth, skin mucus and serum immune parameters of Nile tilapia (Oreochromis niloticus). Five experimental diets with inclusion levels of 0, 1, 2, 4, and 8 g kg^-1 of CSP were fed to Nile tilapia fingerlings (12.77 ± 0.17 g fish^-1) during an eight-week trial. Fish were analyzed on the fourth and eighth week to determine the influences of CSP on growth, skin mucus, and serum immune parameters. Challenging test versus Streptococcus agalactiae was evaluated at the end of the trial. Fish fed with CSP enriched diets displayed a significant increase (P ≤ 0.05) in growth and a decline in feed conversion ratio (P ≤ 0.05). Similarly, skin mucus and serum immune parameters were significantly increased (P ≤ 0.05) in fish fed CSP with respect to the control. The effects were already evident four weeks after the CSP administration. The disease protection test displayed that the fish's survival rate was significantly higher (P < 0.05) in CSP diets over the control. The relative percentage of survival (RSP) was 62.5, 75.0, 58.3, and 37.5 in fish fed diets contained 1, 2, 4, and 8 g kg^-1 CSP, respectively. The best effect on growth, immune response, and disease resistance were shown in Nile tilapia fed with a diet supplementation of 2 g kg^-1 CSP.

Can phytotherapy with polyphenols serve as a powerful approach for the prevention and therapy tool of novel coronavirus disease 2019 (COVID-19)?

Much more serious than the previous severe acute respiratory syndrome (SARS) coronavirus (CoV) outbreaks, the novel SARS-CoV-2 infection has spread speedily, affecting 213 countries and causing ∼17,300,000 cases and ∼672,000 (∼+1,500/day) deaths globally (as of July 31, 2020). The potentially fatal coronavirus disease (COVID-19), caused by air droplets and airborne as the main transmission modes, clearly induces a spectrum of respiratory clinical manifestations, but it also affects the immune, gastrointestinal, hematological, nervous, and renal systems. The dramatic scale of disorders and complications arises from the inadequacy of current treatments and absence of a vaccine and specific anti-COVID-19 drugs to suppress viral replication, inflammation, and additional pathogenic conditions. This highlights the importance of understanding the SARS-CoV-2 mechanisms of actions and the urgent need of prospecting for new or alternative treatment options. The main objective of the present review is to discuss the challenging issue relative to the clinical utility of plants-derived polyphenols in fighting viral infections. Not only is the strong capacity of polyphenols highlighted in magnifying health benefits, but the underlying mechanisms are also stressed. Finally, emphasis is placed on the potential ability of polyphenols to combat SARS-CoV-2 infection via the regulation of its molecular targets of human cellular binding and replication, as well as through the resulting host inflammation, oxidative stress, and signaling pathways.

Spice-infused palmyra palm syrup improved cell-mediated immunity in Wistar Albino rats

Spices attract tremendous attention in the management of viral infections. However, scientific validation is vital to recommend spices as nutraceuticals or functional foods. In the present work, we have selected three spices based on Ayurvedic knowledge and developed a nutraceutical for immunomodulation. Trikatu, a blend of ginger, black pepper, and long pepper, is used in the Indian Ayurvedic system, along with many herbs, for various ailments. We formulated a "Trikatu syrup" (TS) using these three spices and palmyra palm neera. Carbon clearance assay, neutrophil adhesion test, and sheep red blood cell (SRBC)-induced delayed-type hypersensitivity (DTH) reaction was performed to investigate the immunomodulatory potential of TS in Wistar Albino rats. The rats fed with TS showed a dose-dependent increase in footpad thickness compared to control rats, suggesting cell-mediated immunity. The major bioactive piperine in TS was isolated and quantified. PRACTICAL APPLICATIONS: Spices are consumed worldwide as a flavor enhancer in food. Besides, spices have an array of bioactive molecules with a multitude of health benefits. In the backdrop of COVID-19, immunomodulation and antiviral properties of spices are discussed widely. The present study is intended to explore the potential of three selected spices (ginger, black pepper, and long pepper) beyond its application in typical food preparations. The syrup formulated in this study by using these three spices improved cell-mediated immunity in Wistar Albino rats. The study warrants further validation studies of the formulated product for providing indisputable claims for the immunomodulation properties.

Impact of Gallic Acid on Gut Health: Focus on the Gut Microbiome, Immune Response, and Mechanisms of Action

Gallic acid (GA) is a naturally occurring polyphenol compound present in fruits, vegetables, and herbal medicines. According to previous studies, GA has many biological properties, including antioxidant, anticancer, anti-inflammatory, and antimicrobial properties. GA and its derivatives have multiple industrial uses, such as food supplements or additives. Additionally, recent studies have shown that GA and its derivatives not only enhance gut microbiome (GM) activities, but also modulate immune responses. Thus, GA has great potential to facilitate natural defense against microbial infections and modulate the immune response. However, the exact mechanisms of GA acts on the GM and immune system remain unclear. In this review, first the physicochemical properties, bioavailability, absorption, and metabolism of GA are introduced, and then we summarize recent findings concerning its roles in gastrointestinal health. Furthermore, the present review attempts to explain how GA influences the GM and modulates the immune response to maintain intestinal health.

The Role of Dietary Phenolic Compounds in Epigenetic Modulation Involved in Inflammatory Processes

A better understanding of the interactions between dietary phenolic compounds and the epigenetics of inflammation may impact pathological conditions and their treatment. Phenolic compounds are well-known for their antioxidant, anti-inflammatory, anti-angiogenic, and anti-cancer properties, with potential benefits in the treatment of various human diseases. Emerging studies bring evidence that nutrition may play an essential role in immune system modulation also by altering gene expression. This review discusses epigenetic mechanisms such as DNA methylation, post-translational histone modification, and non-coding microRNA activity that regulate the gene expression of molecules involved in inflammatory processes. Special attention is paid to the molecular basis of NF-κB modulation by dietary phenolic compounds. The regulation of histone acetyltransferase and histone deacetylase activity, which all influence NF-κB signaling, seems to be a crucial mechanism of the epigenetic control of inflammation by phenolic compounds. Moreover, chronic inflammatory processes are reported to be closely connected to the major stages of carcinogenesis and other non-communicable diseases. Therefore, dietary phenolic compounds-targeted epigenetics is becoming an attractive approach for disease prevention and intervention.

Jabuticaba (Plinia trunciflora (O. Berg) Kausel) improved the lipid profile and immune system and reduced oxidative stress in streptozotocin-induced diabetic rats

The aim of this study was evaluating the effects of jabuticaba aqueous extract (JPE - 0.5 g/kg) on serum lipid levels, immune system, and oxidative stress parameters of streptozotocin-induced diabetic rats. Administration of JPE for 30 days, by gavage, was able to reduce serum levels of total cholesterol, non-high density lipoprotein (HDL) cholesterol, and triglycerides in diabetic rats. The HDL cholesterol levels increased in both diabetic and healthy rats after JPE treatment. Total leukocyte and lymphocyte counts reduced in diabetic rats, and JPE treatment prevented these diabetes mellitus (DM)-induced changes in the immune system. In addition, the induction of DM also led to dysregulation in the activity of superoxide dismutase and catalase antioxidant enzymes as well as an increase in oxidative stress markers. Treatments with JPE reduced oxidative stress and modulated antioxidant enzyme activities. These data demonstrate the potential of JPE as an adjuvant treatment option for diabetic patients. PRACTICAL APPLICATIONS: Considering that it is very common to observe dyslipidemia in diabetic patients and that these alterations, combined with the increased oxidative stress levels, also common in these patients, can lead to the development of cardiovascular diseases, JPE would be an alternative treatment adjunct to reduce these risks. In addition, although more studies are needed, JPE has the potential to improve the count of total lymphocytes and leukocytes, which could assist in improving the immune response of these patients, who also commonly have a higher risk of infectious diseases. Thus, JPE could be used by these patients, in combination with conventional treatment, in the form of a nutraceutical rich in phenolic compounds.

Nutrigenomic Effects of Long-Term Grape Pomace Supplementation in Dairy Cows

Simple Summary

The aim of this study was to evaluate the effect of grape pomace (GP), the polyphenol-rich agricultural by-product, on dairy cows’ whole-blood transcriptome, milk production and composition. Twelve lactating Holstein-Friesian cows were randomly assigned to two groups; the first received a GP-supplemented diet for 60 days (group GP), whereas the second was given only a basal diet (CTR). The results reveal 40 protein-coding genes differentially expressed in the GP group when compared with the CTR group, but no effects were noticed on milk production, concentrations of crude protein, fat, casein, lactose and urea, or somatic cell count. Compared to CTR, GP had a transcriptomic signature mainly reflecting a reinforced immunogenic response.

Abstract

The increasing demand for more animal products put pressure on improving livestock production efficiency and sustainability. In this context, advanced animal nutrition studies appear indispensable. Here, the effect of grape pomace (GP), the polyphenol-rich agricultural by-product, was evaluated on Holstein-Friesian cows’ whole-blood transcriptome, milk production and composition. Two experimental groups were set up. The first one received a basal diet and served as a control, while the second one received a 7.5% GP-supplemented diet for a total of 60 days. Milk production and composition were not different between the group; however, the transcriptome analysis revealed a total of 40 genes significantly affected by GP supplementation. Among the most interesting down-regulated genes, we found the DnaJ heat-shock protein family member A1 (DNAJA1), the mitochondrial fission factor (MFF), and the impact RWD domain protein (IMPACT) genes. The gene set enrichment analysis evidenced the positive enrichment of ‘interferon alpha (IFN-α) and IFN-γ response’, ‘IL6-JAK-STAT3 signaling’ and ‘complement’ genes. Moreover, the functional analysis denoted positive enrichment of the ‘response to protozoan’ and ‘negative regulation of viral genome replication’ biological processes. Our data provide an overall view of the blood transcriptomic signature after a 60-day GP supplementation in dairy cows which mainly reflects a GP-induced immunomodulatory effect.

Preventive Effects of Kaempferol on High-Fat Diet-Induced Obesity Complications in C57BL/6 Mice

Kaempferol is a dietary flavanol that regulates cellular lipid and glucose metabolism. Its mechanism of action in preventing hepatic steatosis and obesity-related disorders has yet to be clarified. The purpose of this research was to examine kaempferol's antiobesity effects in high-fat diet- (HFD-) fed mice and to investigate its impact on their gut microbiota. Using a completely randomized design, 30 mice were equally assigned to a control group, receiving a low-fat diet, an HFD group, receiving a high-fat diet, and an HFD+kaempferol group, receiving a high-fat diet and kaempferol doses of 200 mg/kg in the diet. After eight weeks, the HFD mice displayed substantial body and liver weight gain and high blood glucose and serum cholesterol levels. However, treatment with kaempferol moderated body and liver weight gain and elevation of blood glucose and serum cholesterol and triglyceride levels. Examination of 16S ribosomal RNA showed that HFD mice exhibited decreased microbial diversity, but kaempferol treatment maintained it to nearly the same levels as those in the control group. In conclusion, kaempferol can protect against obesity and insulin resistance in mice on a high-fat diet, partly through regulating their gut microbiota and moderating the decrease in insulin resistance.

Potential use of polyphenols in the battle against COVID-19

The coronavirus disease 2019 (COVID-19) is a public health emergency of international concern. The rising number of cases of this highly transmissible infection has stressed the urgent need to find a potent drug. Although repurposing of known drugs currently provides an accelerated route to approval, there is no satisfactory treatment. Polyphenols, a major class of bioactive compounds in nature, are known for their antiviral activity and pleiotropic effects. The aim of this review is to assess the effects of polyphenols on COVID-19 drug targets as well as to provide a perspective on the possibility to use polyphenols in the development of natural approaches against this viral disease.

Flavonoids as Anticancer Agents

Flavonoids are polyphenolic compounds subdivided into 6 groups: isoflavonoids, flavanones, flavanols, flavonols, flavones and anthocyanidins found in a variety of plants. Fruits, vegetables, plant-derived beverages such as green tea, wine and cocoa-based products are the main dietary sources of flavonoids. Flavonoids have been shown to possess a wide variety of anticancer effects: they modulate reactive oxygen species (ROS)-scavenging enzyme activities, participate in arresting the cell cycle, induce apoptosis, autophagy, and suppress cancer cell proliferation and invasiveness. Flavonoids have dual action regarding ROS homeostasis—they act as antioxidants under normal conditions and are potent pro-oxidants in cancer cells triggering the apoptotic pathways and downregulating pro-inflammatory signaling pathways. This article reviews the biochemical properties and bioavailability of flavonoids, their anticancer activity and its mechanisms of action.

The Regulation of Host Intestinal Microbiota by Polyphenols in the Development and Prevention of Chronic Kidney Disease

Polyphenols are essential antioxidants in our regular diet, and have shown potential antibacterial effects. Other important biological effects, such as anticancer or antibacterial activities, have been demonstrated by some polyphenols. In recent years, the benefits of polyphenols to human health have attracted increasing attention from the scientific community. Recent studies have shown that polyphenols such as anthocyanin, catechin, chlorogenic acid, and resveratrol can inhibit pathogenic bacteria such as Escherichia coli and Salmonella to help regulate intestinal microflora. An imbalance of intestinal microflora and the destruction of intestinal barrier function have been found to have a potential relationship with the occurrence of chronic kidney disease (CKD). Specifically, they can aberrantly trigger the immune system to cause inflammation, increase the production of uremic toxins, and further worsen the condition of CKD. Therefore, the maintenance of intestinal microflora and the intestinal tract in a stable and healthy state may be able to "immunize" patients against CKD, and treat pre-existing disease. The use of common antibiotics may lead to drug resistance in pathogens, and thus beneficial polyphenols may be suitable natural substitutes for antibiotics. Herein we review the ability of different polyphenols, such as anthocyanin, catechin, chlorogenic acid, and resveratrol, to regulate intestinal microorganisms, inhibit pathogenic bacteria, and improve inflammation. In addition, we review the ability of different polyphenols to reduce kidney injury, as described in recent studies.

Recent Advances on the Anti-Inflammatory and Antioxidant Properties of Red Grape Polyphenols: In Vitro and In Vivo Studies

In this review, special emphasis will be placed on red grape polyphenols for their antioxidant and anti-inflammatory activities. Therefore, their capacity to inhibit major pathways responsible for activation of oxidative systems and expression and release of proinflammatory cytokines and chemokines will be discussed. Furthermore, regulation of immune cells by polyphenols will be illustrated with special reference to the activation of T regulatory cells which support a tolerogenic pathway at intestinal level. Additionally, the effects of red grape polyphenols will be analyzed in obesity, as a low-grade systemic inflammation. Also, possible modifications of inflammatory bowel disease biomarkers and clinical course have been studied upon polyphenol administration, either in animal models or in clinical trials. Moreover, the ability of polyphenols to cross the blood-brain barrier has been exploited to investigate their neuroprotective properties. In cancer, polyphenols seem to exert several beneficial effects, even if conflicting data are reported about their influence on T regulatory cells. Finally, the effects of polyphenols have been evaluated in experimental models of allergy and autoimmune diseases. Conclusively, red grape polyphenols are endowed with a great antioxidant and anti-inflammatory potential but some issues, such as polyphenol bioavailability, activity of metabolites, and interaction with microbiota, deserve deeper studies.

MicroRNA Determines the Fate of Intestinal Epithelial Cell Differentiation and Regulates Intestinal Diseases

The rapid self-renewal of intestinal epithelial cells enhances intestinal function, promotes the nutritional needs of animals and strengthens intestinal barrier function to resist the invasion of foreign pathogens. MicroRNAs (miRNAs) are a class of short-chain, non-coding RNAs that regulate stem cell proliferation and differentiation by down-regulating hundreds of conserved target genes after transcription via seed pairing to the 3' untranslated regions. Numerous studies have shown that miRNAs can improve intestinal function by participating in the proliferation and differentiation of different cell populations in the intestine. In addition, miRNAs also contribute to disease regulation and therefore not only play a vital role in the gastrointestinal disease management but also act as blood or tissue biomarkers of disease. As changes to the levels of miRNAs can change cell fates, miRNA-mediated gene regulation can be used to update therapeutic strategies and approaches to disease treatment.

Colonic Bacteria-Transformed Catechin Metabolite Response to Cytokine Production by Human Peripheral Blood Mononuclear Cells

Human gut microbes are a profitable tool for the modification of food compounds into biologically active metabolites. The biological properties of catechins have been extensively investigated. However, the bioavailability of catechin in human blood plasma is very low. This study aimed to determine the biotransformed catechin metabolites and their bioactive potentials for modulating the immune response of human peripheral blood mononuclear cells (PBMCs). Biotransformation of catechin was carried out using in-vitro gut microbial biotransformation method, the transformed metabolites were identified and confirmed by gas chromatography-mass spectrometry (GC–MS) and high-performance liquid chromatography-mass spectrometry (HPLC–MS). Present observations confirmed that the catechin was biotransformed into 11 metabolites upon microbial dehydroxylation and C ring cleavage. Further, immunomodulatory potential of catechin metabolites was analyzed in peripheral blood mononuclear cells (PBMCs). We found up-regulation of anti-inflammatory cytokine (IL-4, IL-10) and down-regulation of pro-inflammatory (IL-16, IL-12B) cytokine may be due to Th2 immune response. In conclusion, biotransformed catechin metabolites enhance anti-inflammatory cytokines which is beneficial for overcoming inflammatory disorders.

Polydatin and Resveratrol Inhibit the Inflammatory Process Induced by Urate and Pyrophosphate Crystals in THP-1 Cells

Resveratol (RES) and its natural precursor polydatin (PD) are polyphenols that may display a broad variety of beneficial effects including anti-inflammatory properties. This study aimed to investigate the role of RES and PD in the inflammatory process induced by monosodium urate (MSU) and calcium pyrophosphate (CPP) crystals in vitro. A monocytic cell line (THP-1) was primed for 3 hours with phorbol myristate acetate (100 ng/mL) and stimulated with synthetic MSU (0.05 mg/mL) and CPP (0.025 mg/mL) crystals. RES and PD were added to cultures concurrently with the crystals, or as 2-hour pretreatment. The effect of the two polyphenols was evaluated on intracellular and extracellular IL-1β levels, NACHT-LRRPYD-containing protein-3 (NLRP3) inflammasome expression, reactive oxygen species (ROS) and nitric oxide (NO) production, and the assessment of crystal phagocytosis. RES and PD strongly inhibited IL-1β induced by crystals after cell pretreatment. Cell pretreatment was effective also in reducing IL-1 mRNA expression while no effect was observed on NLRP3 gene expression. RES and PD had no effect on crystal phagocytosis when used as pretreatment. Both polyphenols were significantly effective in inhibiting ROS and NO production. Our results demonstrated that RES and PD are effective in inhibiting crystal-induced inflammation. Data obtained after cell pretreatment allow us to hypothesize that these polyphenols act on specific signaling pathways, preventing inflammation.

Intestinal anti-inflammatory activity of xique-xique (Pilosocereus gounellei A. Weber ex K. Schum. Bly. Ex Rowl) juice on acetic acid-induced colitis in rats

Inflammatory bowel disease (IBD) is characterized by severe mucosal damage in the intestine and a deregulated immune response. Natural products derived from plants that are rich in bioactive compounds are used by many patients with IBD. Xique-xique (Pilosocereus gounellei) is a cactus of the Caatinga family that has been used by the local population for food and medicinal purposes. The intestinal anti-inflammatory effect of xique-xique cladode juice was evaluated in the present study. A dose of 5 mL kg^-1 had a protective effect on intestinal inflammation, with an improvement in macroscopic damage, and a decrease in pro-inflammatory markers and oxidative stress, in addition to preserving the colonic tissue. Immunohistochemical analysis revealed the downregulation of IL-17, NF-κB, and iNOS, and upregulation of SOCs-1, ZO-1, and MUC-2. These protective effects could be attributed to the phenolic compounds as well as the fibers present in xique-xique juice. Further studies are needed before suggesting the use of xique-xique juice as a new alternative for treating IBD.

Quercetin reduces atherosclerotic lesions by altering the gut microbiota and reducing atherogenic lipid metabolites

AIMS

Epidemiological studies have correlated cardiovascular disease and atherosclerosis with lifestyle factors such as sedentary behaviour and a high-calorie diet. Recent studies of pathogenesis have highlighted the significance of the intestinal microbiota and chronic inflammation with respect to both the onset and development of atherosclerosis. This study examined the hypothesis that the oral administration of quercetin to low-density lipoprotein receptor-null (Ldlr^-/- ) mice would improve gut health by altering the gut microbiota and controlling the levels of atherogenic lipid metabolites and proinflammatory mediators in the intestine and serum.

METHODS AND RESULTS

Mice were maintained on a high-fat diet with or without oral quercetin administration for 12 weeks. Quercetin treatment suppressed body weight gains and reduced the extent of atherosclerotic lesions in the aortic sinus. Reduced malondialdehyde and increased interleukin 6 levels further indicated the protective effect of quercetin against immune/inflammatory responses and oxidative stress. Furthermore, quercetin led to decreased intestinal levels of cholesterol, lysophosphatidic acids and atherogenic lysophosphatidylcholine (LPC 18:1) and an increased level of coprostanol. A phylum-level microbial analysis revealed that quercetin treatment reduced the abundance of Verrocomicrobia and increased microbiome diversity and the abundances of Actinobacteria, Cyanobacteria and Firmicutes. A Spearman analysis revealed negative correlations of Actinobacteria with intestinal and plasma LPC 18:1 and caecal cholesterol levels and of Firmicutes and Cyanobacteria with the plasma LPC 18:1 level.

CONCLUSIONS

This study demonstrated the ability of quercetin treatment to reduce lipid levels, as well as the areas of atherosclerotic lesions and sizes of plaques. This treatment also altered the composition of the gut microbiota and decreased the levels of atherogenic lipid metabolites.

SIGNIFICANCE AND IMPACT OF THE STUDY

Oral quercetin treatment may represent a new approach to mitigating the onset and development of atherosclerosis.

Immunomodulatory Activities of Sambucus javanica Extracts in DMBA-Exposed BALB/c Mouse

Purpose: Accumulating evidence shows the genus of Sambucus exerts a broad spectrum of medicinal potencies such as anticancer, antiviral, antibacterial, and antidiabetes. Based on the previous studies, we hypothesized that bioactive compounds of Sambucus might alter several biological systems, including the immune system. Therefore, this study extensively aimed to evaluate the immunomodulatory activities of Sambucus javanica extracts in 7,12-dimethylbenz[a] anthracene (DMBA)-treated BALB/c mouse. Methods: The experimental mice were orally administrated with 2.8 mg.kg-1 BW of DMBA for ten times within a month. After that, the mice were treated by S. javanica berries and leaves extracts for 2 weeks. Subsequently, the inflammation rate was evaluated by using flow cytometry analysis, whereas the necrosis incidences were observed by hematoxylin & eosin staining. Results: Based on the results, we found the expression of tumor necrosis factor alpha (TNF-α) and interferon gamma (IFN-ɣ) were increased however after treated by S. javanica berries and leaves extracts were significantly decreased. In the same way, necrosis incidence was increased in the DMBA-treated group however it was diminished with S. javanica extracts treatment. Conclusion: Together, these results suggested that S. javanica extracts have immunomodulatory activities to suppress inflammation and reduce necrosis incidence in experimental mice.