LitCovid-sentences  

PMC:7647877 / 28594-77333 JSONTXT 10 Projects

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Id Subject Object Predicate Lexical cue
T177 0-62 Sentence denotes Immunonutrition: the role of specific nutrients and microbiota
T178 63-208 Sentence denotes An optimal nutritional status guarantees the main modulating processes of inflammatory and oxidative stress, both connected to the immune system.
T179 209-314 Sentence denotes The metabolic system applied for biosynthesis and energy request needs many different dietary components.
T180 315-523 Sentence denotes In fact, some nutrients and their metabolites are direct regulators of gene expression of the immune compartment and play a key role in the maturation, differentiation and responsiveness of immune cells [61].
T181 524-656 Sentence denotes It is easy to understand that an adequate and balanced supply of these nutrients is essential to set an appropriate immune response.
T182 657-791 Sentence denotes Basically, good nutrition creates a setting in which the immune system can respond appropriately to challenge, whatever this might be.
T183 792-903 Sentence denotes On the contrary, poor nutrition produces an environment in which the immune system cannot respond well [62–64].
T184 904-1050 Sentence denotes Furthermore, nutritional status, the role of diet and lifestyle may play an important part in different severe infections, especially in COVID-19.
T185 1051-1229 Sentence denotes The importance of nutrition as a mitigation strategy to support immune function, is reachable identifying food groups and key nutrients as defense against respiratory infections.
T186 1230-1451 Sentence denotes A balanced diet, rich in some foods, is associated with anti-inflammatory and immunomodulatory compounds, including vitamins (C, D, and E) and minerals (zinc and selenium), and may influence human nutritional status [16].
T187 1452-1538 Sentence denotes During this COVID-19 pandemic many myths surfaced on how strengthen the immune system.
T188 1539-1672 Sentence denotes Several research publications have focused on the role of diet and specific nutrients, some focusing on respiratory viral infections.
T189 1673-1800 Sentence denotes The most of micronutrients have been identified as the main responsible for maintenance the complex needs of the immune system.
T190 1801-1894 Sentence denotes Below we will focus on the main nutrients with specific reference to respiratory health [65].
T191 1896-1915 Sentence denotes Omega 3 fatty acids
T192 1916-2064 Sentence denotes Reactive oxygen species create a pro-oxidant environment against which the body needs protection through vitamins, enzymes and antioxidant feedings.
T193 2065-2277 Sentence denotes Particularly, omega-3 fatty acids are known to exert anti-inflammatory and antioxidant properties [66, 67], and to support the immune system, specifically by helping to resolve the inflammatory response [63, 68].
T194 2278-2463 Sentence denotes The intake of omega-3 fatty acids from fish and seafood has been shown to trigger anti-inflammatory reactions via oxygenated metabolites (oxylipins), including resolvins and protectins.
T195 2464-2703 Sentence denotes Omega-3 fatty acids include linolenic acid (ALA) consumed from various plant sources and eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) consumed especially from fish and seafood sources, such as salmon, mackerel, and tuna [69].
T196 2704-2915 Sentence denotes Notably, the omega-3 fatty acids EPA and DHA involved in the inflammation process, are enzymatically converted to specialized pro-resolving mediators (SPMs) known as resolvins, protectins, and maresins [66, 67].
T197 2916-3079 Sentence denotes These molecules, alongside with others, function together to orchestrate the resolution of inflammation and to support healing, including in the respiratory tract.
T198 3080-3202 Sentence denotes Deficiencies of omega-3 fatty acids EPA and DHA are accountable for delayed or suboptimal resolution of inflammation [70].
T199 3203-3365 Sentence denotes This could be very important in the context of severe COVID-19, which manifests as uncontrolled inflammation, the so-called cytokine storm, linked with ARDS [71].
T200 3367-3385 Sentence denotes Oleoylethanolamide
T201 3386-3549 Sentence denotes Oleoylethanolamide (OEA), synthesized in the gastrointestinal tract, is a bioactive lipid mediator derived from the omega-9 monounsaturated fatty acid, oleic acid.
T202 3550-3741 Sentence denotes Based on previous evidences, OEA showed anti-inflammatory activities, a role in modulation of immune response, anti-oxidant effects and stimulation of lipolysis and fatty acid oxidation [72].
T203 3742-3949 Sentence denotes In this context OEA is considered an endocannabinoid-like lipid, which interacts with the peroxisome proliferator-activated receptor-alpha (PPAR-α) and intervenes during the anti-inflammatory processes [73].
T204 3950-4168 Sentence denotes Scientific researchers recently showed that endocannabinoid system is involved in the management of infectious agents such as viruses, bacteria, and some protozoa, also reducing inflammation and pain in the lungs [74].
T205 4169-4480 Sentence denotes In view of the fact that SARS-CoV-2 infection leads to increase the pro-inflammatory cytokines, including IL-6 and IL-1β in COVID-19 patients via binding to the TLRs, an important components of the innate immune system, it is assumed that OEA inhibits this pathway through its anti-inflammatory properties [75].
T206 4481-4698 Sentence denotes OEA binds with high affinity to PPAR-α receptors and increases the expression level of anti-inflammatory cytokine such as IL-10, then initiates a cascade of events, which can attenuate the inflammatory responses [73].
T207 4699-4856 Sentence denotes Furthermore, OEA attenuates the inflammatory responses modulating the expression of TLR-4, and interfering with the ERK1/2/AP-1/STAT3 signaling cascade [73].
T208 4857-5004 Sentence denotes OEA may modulate cross-talk between PPAR-α and TLRs and regulates the inflammatory responses with beneficial synergistic effect against SARS-CoV-2.
T209 5005-5340 Sentence denotes Nowadays, discovering therapeutic options from currently available agents appears to be essential for the treatment and prophylaxis of this pandemic, especially in obese patients with comorbidities [76] and this bioactive lipid mediator can be considered as a novel potential pharmacological alternative for the management of COVID-19.
T210 5342-5351 Sentence denotes Vitamin A
T211 5352-5484 Sentence denotes The role of vitamin A and its metabolites in the immune system and host susceptibility is discussed in a series of reviews [77, 78].
T212 5485-5804 Sentence denotes This nutrient is involved in normal differentiation of epithelial tissue, furthermore retinoic acid is essential for imprinting T and B cells with gut-homing specificity and T array cells and IgA cells in intestinal tissues [79], thus enhancing the intestinal immune response and supporting the intestinal barrier [80].
T213 5805-6030 Sentence denotes Carotenoids (both provitamin A and non-provitamin A carotenoids) have immunoregulatory actions including the reduction of the toxic effects of ROS and the regulation of membrane fluidity and gap-junctional communication [81].
T214 6031-6159 Sentence denotes Vitamin A deficiency impairs barrier function, impairs immune responses and increases susceptibility to a variety of infections.
T215 6160-6265 Sentence denotes Furthermore, many aspects of innate immunity, in addition to barrier function, are affected by vitamin A.
T216 6266-6490 Sentence denotes For example, vitamin A regulates the number and function of NK cells [82], contributes to the phagocytic and oxidative activity of the macrophage burst [79] and controls the maturation of neutrophils and its deficiency [83].
T217 6491-6573 Sentence denotes The activity of natural killer cells is therefore reduced by vitamin A deficiency.
T218 6574-6726 Sentence denotes The impact of vitamin A on acquired immunity is however clear since it is involved in the development and differentiation of Th1 and Th2 cells [62, 79].
T219 6727-6914 Sentence denotes Moreover there is evidence that vitamin A deficiency alters the balance of Th1 and Th2 cells, decreasing the Th2 response, without affecting or, in some cases, enhancing the Th1 response.
T220 6915-6992 Sentence denotes This suggests that vitamin A increases the Th1 cell average in immunity [84].
T221 6993-7326 Sentence denotes However, studies in several experimental models have shown how the retinoic acid metabolite of vitamin A reduces the responses of Th1-type cells (cytokines, cytokine receptors and the transcription factor T-bet, which promotes Th1), improving responses to Th2-type cells (cytokines and Th2-favoring transcription factor GATA-3) [62].
T222 7327-7469 Sentence denotes Indeed, it maintains the normal Th2 response mediated by antibodies by suppressing the production of IL-12, TNF-α and IFN-γ by Th1 cells [85].
T223 7470-7665 Sentence denotes Vitamin A appears to be important in the differentiation of regulatory T lymphocytes by suppressing Th17 differentiation, which have implications for the control of adverse immune reactions [86].
T224 7666-7845 Sentence denotes It helps regulate the production of IL-2 and the pro-inflammatory TNF-γ, which activates the phagocytic and oxidative action of the macrophages activated during inflammation [79].
T225 7846-7969 Sentence denotes It ensures the normal functioning of B lymphocytes, necessary for the generation of antibody responses to the antigen [85].
T226 7970-8156 Sentence denotes Retinoic acid appears to promote the movement of T cells to gut-associated lymphoid tissue and, interestingly, some gut-associated immune cells are able to synthesize retinoic acid [87].
T227 8157-8333 Sentence denotes Vitamin A deficiency is associated with increased morbidity and mortality in children and appears to predispose to respiratory infections, diarrhea and severe measles [88, 89].
T228 8334-8464 Sentence denotes Moreover, supplementing vitamin A in deficient children improves recovery from infectious diseases and reduces mortality [78, 90].
T229 8465-8558 Sentence denotes The Recommended Dietary Allowance (RDA) for vitamin A reports a range of 900–700 µg/day [91].
T230 8560-8569 Sentence denotes Vitamin C
T231 8570-8680 Sentence denotes The role of vitamin C in immunity and in host susceptibility to infection has been scientifically proven [92].
T232 8681-8841 Sentence denotes Vitamin C, in fact, is necessary for the biosynthesis of collagen and is essential for maintaining epithelial integrity and protecting against oxidative stress.
T233 8842-9089 Sentence denotes It protects cell membranes from damage caused by free radicals, so as to support the integrity of the epithelial barriers [79], also improves keratinocytic differentiation and lipid synthesis as well as fibroblast proliferation and migration [92].
T234 9090-9505 Sentence denotes It plays a role in various aspects of immunity, in fact it is involved in the proliferation, function and movement of neutrophils, monocytes and phagocytes [82] and the migration of leukocytes to sites of infection, phagocytosis and bacterial killing, in the activity of natural killer cells and in the function of T lymphocytes (especially CD8 cytotoxic T lymphocytes) and in the production of antibodies [79, 82].
T235 9506-9729 Sentence denotes Vitamin C is also involved in apoptosis and elimination of depleted neutrophils from macrophage infection sites [92] and attenuates the formation of extracellular trap (NET), thus reducing the associated tissue damage [92].
T236 9730-9863 Sentence denotes Infections have a significant impact on vitamin C levels, due to the increased energy needs required by the body during inflammation.
T237 9864-10003 Sentence denotes This nutrient, in fact, promotes the proliferation of lymphocytes, with a consequent increase in the generation of antibodies [79, 85, 92].
T238 10004-10274 Sentence denotes It is well known that infections increase oxidative stress and usually activate phagocytes that release ROS, so vitamin C is a well-known antioxidant that can counteract these effects by increasing phagocytosis and ROS generation and improving microbial killing [92–94].
T239 10275-10400 Sentence denotes Furthermore, supplementation with vitamin C appears to be able to prevent and treat respiratory and systemic infections [92].
T240 10401-10578 Sentence denotes High levels of this nutrient can enhance antimicrobial effects and increase serum levels of complement proteins, also playing an important role in IFN-γ production [85, 92, 95].
T241 10579-10702 Sentence denotes Low levels of vitamin C are responsible for an increased susceptibility to severe respiratory infections such as pneumonia.
T242 10703-10893 Sentence denotes Indeed, a meta-analysis reported a significant reduction in the risk of pneumonia with vitamin C supplementation, particularly in individuals with a low dietary intake of this nutrient [96].
T243 10894-11105 Sentence denotes Vitamin C supplementation has also been demonstrated to reduce the duration and severity of upper respiratory tract infections, such as the common cold, especially in people under increased physical stress [96].
T244 11106-11210 Sentence denotes Currently, there are limited recommendations for taking vitamin C supplementation against COVID-19 [97].
T245 11211-11380 Sentence denotes Nevertheless, there is sufficient evidence to conduct several clinical trials to assess vitamin C efficacy in COVID-19 prevention and treatment (www.clinicaltrials.gov).
T246 11381-11470 Sentence denotes Previously, doses of 1–2 g/day were effective in preventing upper respiratory infections.
T247 11471-11615 Sentence denotes As those levels are not attainable through dietary sources, supplementation may be advised for those at a higher risk of respiratory infections.
T248 11616-11690 Sentence denotes Doses above 200 mg/day may not be beneficial for healthy individuals [98].
T249 11692-11701 Sentence denotes Vitamin D
T250 11702-11824 Sentence denotes Many reviews discuss the role of vitamin D and its metabolites in host immunity and susceptibility to infections [99–101].
T251 11825-12051 Sentence denotes Vitamin D receptors have been identified in most immune cells, of which some can also synthesize the active form of vitamin D from its precursor, therefore suggesting that might have important immunoregulatory properties [99].
T252 12052-12218 Sentence denotes Vitamin D is synthesized at skin level in the presence of UV-light from cholesterol and it is also taken up from the diet (fish, eggs, fortified milk, and mushrooms).
T253 12219-12526 Sentence denotes The active form of vitamin D, calcitriol (1,25-dihydroxy vitamin D3), formed following kidney and liver hydroxylation, is most renowned for its regulating role in calcium homeostasis and bone health status, but it has also been shown to regulate the immune system, mainly in the functioning of T-cell [102].
T254 12527-12801 Sentence denotes Among the main functions of vitamin D, its ability to improve the integrity of the epithelium has mainly been observed as well as the ability to induce the synthesis of an antimicrobial peptide in epithelial cells and macrophages, thus directly improving host defense [103].
T255 12802-13011 Sentence denotes Vitamin D also promotes the differentiation of monocytes from macrophages [95], promotes the movement and phagocyability of macrophages [79], superoxide production and bacterial killing by innate immune cells.
T256 13012-13095 Sentence denotes Hence, it promotes the processing of antigen presentation by dendritic cells [104].
T257 13096-13243 Sentence denotes Calcitriol regulates the expression of antimicrobial proteins (cathelicidin and defensin), which directly kill pathogens, especially bacteria [99].
T258 13244-13423 Sentence denotes It inhibits the production of IFN-γ [71] and reduces the expression of pro-inflammatory cytokines by increasing the expression of anti-inflammatory cytokines by macrophages [105].
T259 13424-13631 Sentence denotes Calcitriol modulates antimicrobial proteins (cathelicidin and β-defensin), responsible for modifying the intestinal microbiota, favoring a healthy composition and supporting the intestinal barrier [80, 106].
T260 13632-13884 Sentence denotes It also helps protect the lungs against infection, increases the expression of the tight junction protein, E-cadherin and connexion 43 in the intestine, maintains renal-epithelial barrier function and improves corneal epithelial barrier function [104].
T261 13885-14068 Sentence denotes The 1,25-dihydroxyvitamin D3 can bind to a specific nuclear receptor (vitamin D receptor, VDR) and its role for both the innate and adaptive immune systems has been highlighted [107].
T262 14069-14173 Sentence denotes Moreover, vitamin D has been controversially discussed for its role in influenza prevention and therapy.
T263 14174-14316 Sentence denotes As shown in literature, 1,25-dihydroxyvitamin D3 undoubtedly plays a strong role as an immunomodulating agent in adaptive and innate immunity.
T264 14317-14464 Sentence denotes Different reviews have also reported that individuals with low vitamin D status have a higher risk of viral respiratory tract infections [99, 108].
T265 14465-14795 Sentence denotes Several systematic reviews show that levels of this vitamin are inversely related to respiratory tract infection [109, 110] and underlines that individuals with low vitamin D levels show an increased risk of viral tract infections, concluding that its supplementation can reduce the risk of respiratory tract infections [82, 111].
T266 14796-14986 Sentence denotes Some studies on the influenza prevention provide a negative correlation between the enhanced post-immunization vaccine and obese patients, because obesity involves a deficiency of vitamin D.
T267 14987-15174 Sentence denotes According to most authors, more randomized controlled trials with large populations are needed to explore the preventive effect of vitamin D supplementation on viral flu infections [107].
T268 15176-15185 Sentence denotes Vitamin E
T269 15186-15359 Sentence denotes Vitamin E exists mainly in the form of tocopherols present in high amounts in nuts and vegetable oils, whereas tocotrienols are found predominantly in some seeds and grains.
T270 15360-15440 Sentence denotes This vitamin is involved in immunity and host susceptibility to infection [112].
T271 15441-15677 Sentence denotes A positive association was demonstrated between plasma vitamin E and cell-mediated immune responses, while a negative association was observed among plasma vitamin E and the risk of infections in healthy adults over 60 years of age [8].
T272 15678-15796 Sentence denotes It protects cell membranes from damage caused by free radicals and supports the integrity of epithelial barriers [79].
T273 15797-15957 Sentence denotes Vitamin E has also been shown to regulate the maturation and functions of dendritic cells, which are important for the innate and adaptive immune systems [112].
T274 15958-16455 Sentence denotes The immune response mechanisms in which vitamin E is involved are as follows: (i) maintains or improves the cytotoxic activity of NK cells [82] and reduces prostaglandin E2 (PGE2) production by the inhibition of cyclooxygenase-2 (COX-2) activity, mediated through decreasing of nitric oxide production [64, 112, 113]; (ii) the improvement of immune synapse formation in naive T cells, increasing the percentage of memory experienced with the antigen [112]; (iii) the modulation of Th1/Th2 balance.
T275 16456-16602 Sentence denotes Indeed it improves lymphocyte proliferation and T cell mediated functions, optimizes and improves the Th1 response and suppress Th2 response [95].
T276 16603-16753 Sentence denotes The role of this vitamin in the prevention of infections such as influenza has been discussed, but more controlled studies in humans are needed [114].
T277 16754-16944 Sentence denotes Notably, it is accepted that vitamin E may exert its immune-enhancing effects by scavenging oxygen species to reduce oxidative stress [112] and it may induce anti-inflammatory effects [113].
T278 16945-17129 Sentence denotes In particular, it appears to be an important fat-soluble antioxidant that hinders the chain reaction induced by free radicals (chain breaking effect) and protects cells from them [95].
T279 17131-17135 Sentence denotes Zinc
T280 17136-17393 Sentence denotes Zinc is considered a “guardian” for the body, as it plays an essential role in the functioning of the immune system [115], plays a central role in cell growth and differentiation of the immune system cells that have rapid differentiation and turnover [116].
T281 17394-17682 Sentence denotes Most of the studies have recently reported a very interesting evaluation of the function of zinc in antiviral immunity, suggesting how it can play a role in host defense against RNA viruses, inhibiting the RNA polymerase required by RNA viruses (such as coronaviruses) to replicate [117].
T282 17683-17769 Sentence denotes The zinc-binding metallothionein seems to play an important role in antiviral defense.
T283 17770-17985 Sentence denotes Zinc deficiency has a marked impact on bone marrow, decreasing the number of immune precursor cells, with reduced output of naive B lymphocytes, and causes thymic atrophy, reducing the output of naive T lymphocytes.
T284 17986-18147 Sentence denotes Therefore, zinc is essential for cell growth and differentiation of immune cells, helping to modulate the cytokine release and trigger CD8+ T cell proliferation.
T285 18148-18428 Sentence denotes Among the main activities of zinc in immune function there are: maintaining skin and mucosal integrity (e.g., cofactor for metalloenzymes required for cell membrane repair) [118]; improving the cytotoxic activity of NK cells [79, 82] and the phagocytic capacity of monocytes [64].
T286 18429-18685 Sentence denotes It is involved in the complement activity and in the production of IFN-γ [92, 95]; it is an important anti-inflammatory agent [119] and helps modulate the release of cytokines [95] by attenuating the development of pro-inflammatory Th17 and Th9 cells [64].
T287 18686-18858 Sentence denotes Furthermore, by influencing the generation of cytokines such as IL-2, IL-6 and TNF, it has antioxidant effects that protect against ROS and reactive nitrogen species [120].
T288 18859-19012 Sentence denotes Zinc also induces the proliferation of cytotoxic T cells [62] and is involved in the production of Th1 cytokines and thus supports the Th1 response [95].
T289 19013-19286 Sentence denotes It is essential for the intracellular binding of tyrosine kinase to T cell receptors, which is required for T cell development, differentiation and activation [118] and induces the development of Treg cells and is therefore important for maintaining immune tolerance [120].
T290 19287-19451 Sentence denotes Finally, zinc is involved in the production of antibodies [79, 121] and it is important to maintain immune tolerance in recognizing the “self” from “non-self” [64].
T291 19452-19573 Sentence denotes Low zinc status impairs many aspects of innate immunity, including phagocytosis, respiratory burst and NK cells activity.
T292 19574-19668 Sentence denotes Zinc also supports the release of neutrophil extracellular traps, that capture microbes [122].
T293 19669-19799 Sentence denotes Zinc malabsorption also displays severe immune impairments and increased susceptibility to bacterial, viral and fungal infections.
T294 19800-19968 Sentence denotes It has widely been suggested that increasing zinc intakes may be useful against COVID-19 infections, by reducing viral replication and lower respiratory symptoms [123].
T295 19969-20180 Sentence denotes Recent systematic reviews report a shorter duration of the common cold in adults with a good level of zinc and a reduced incidence of mortality when it is supplemented to adults with severe pneumonia [124, 125].
T296 20181-20261 Sentence denotes Further research will be necessary to support a zinc supplementation in advices.
T297 20262-20526 Sentence denotes The RDA of zinc, according to the Dietary Recommendation Intake (DRI), is 8–11 mg/day for adults (tolerable upper intake level 40 mg/day), suggesting that a zinc intake of 30–50 mg/day might aid in the RNA viruses control, such as influenza and coronaviruses [98].
T298 20528-20536 Sentence denotes Selenium
T299 20537-20665 Sentence denotes Selenium is an essential micronutrient that plays a significant role in many physiological processes including immune responses.
T300 20666-20818 Sentence denotes The immune system needs an adequate intake of this nutrient mostly through its incorporation into selenoproteins to exerts its biological effects [126].
T301 20819-20992 Sentence denotes In fact, it has an important antioxidant role to quench ROS, influencing leukocyte and NK cell function and consequently modulating the host antioxidant defense system [85].
T302 20993-21140 Sentence denotes In fact, selenoproteins act as redox regulators and cellular antioxidants, potentially counteracting the ROS produced during oxidative stress [82].
T303 21141-21267 Sentence denotes Selenium is involved in T-lymphocyte proliferation and the humoral system [85], especially in immunoglobulin production [127].
T304 21268-21382 Sentence denotes It helps improve Th cell counts and maintain antibody levels [85] and also increases the production of IFN-γ [95].
T305 21383-21583 Sentence denotes Selenium deficiencies have been associated with viral infections such as influenza, determining adaptive and innate immunity responses and leading to a high level of virus-related pathogenicity [128].
T306 21584-21720 Sentence denotes Low concentrations of selenium in humans have been linked to the reduced activity of NK cells and the increase in mycobacterial disease.
T307 21721-21870 Sentence denotes Moreover, selenium deficiency has been shown to allow mutations of coxsackievirus, poliovirus and murine influenza virus, increasing their virulence.
T308 21871-21993 Sentence denotes Dietary selenium supplementations were suggested as adjuvant therapies of influenza, supporting the immune response [129].
T309 21994-22207 Sentence denotes The beneficial effects of a higher selenium status have been supported for some viral infections, although there are some studies that do not conclusively demonstrate effective improvements in anti-viral immunity.
T310 22208-22347 Sentence denotes On the contrary, the antioxidant properties of some selenoproteins have been suggested to contribute to boosting anti-viral immunity [129].
T311 22348-22593 Sentence denotes Currently, the recommended amounts of adequate selenium intake for adults range between 25 and 100 μg/die [130], with an average of 60 μg/die for men and 53 μg/die for women [131]; the tolerable upper intake level is set at 300–450 μg/die [132].
T312 22594-22698 Sentence denotes More research is needed to improve knowledge of selenium metabolism and requirements for optimal health.
T313 22699-22852 Sentence denotes The relationships between selenium dietary intake and health status, or risk of disease, are complex and require elucidation to inform clinical practice.
T314 22854-22858 Sentence denotes Iron
T315 22859-22957 Sentence denotes The role of iron in immunonutrition has been widely discussed and confirmed by many studies [133].
T316 22958-23158 Sentence denotes Iron is required for a number of different cellular functions and there is a constant balance between iron uptake, transport, storage, and utilization required to maintain iron homeostasis [134, 135].
T317 23159-23291 Sentence denotes As the body lacks a defined mechanism for the active excretion of iron, iron balance is mainly regulated at the point of absorption.
T318 23292-23404 Sentence denotes Iron deficiency induces thymus atrophy and has multiple effects on immune function in human subjects [133, 136].
T319 23405-23638 Sentence denotes The effects of this micronutrient in modulating the immune system include the regulation of T cell differentiation and proliferation [85], also helping to regulate the interplay between helper T cells and cytotoxic T cells [95, 137].
T320 23639-23811 Sentence denotes It also play a role in IFN-γ production and participates in the production of cytokines, in fact it is involved in the regulation of the production and action of cytokines.
T321 23812-24045 Sentence denotes It forms highly toxic hydroxyl radicals, involved in the killing of bacteria by neutrophils and it is a component of enzymes critical for the functioning of immune cells (e.g. ribonucleotide reductase involved in DNA synthesis) [95].
T322 24046-24172 Sentence denotes The iron-rich state promotes the M2-like macrophage phenotype and negatively regulates the M1 pro-inflammatory response [138].
T323 24173-24296 Sentence denotes This nutrient is necessary for the generation of ROS, that kill pathogens (by neutrophils) during the oxidative burst [85].
T324 24297-24394 Sentence denotes Finally, it appears to be essential for the differentiation and growth of epithelial tissue [95].
T325 24395-24534 Sentence denotes Iron at doses above the upper threshold has been associated with increased risk of malaria and other infections, including pneumonia [139].
T326 24535-24665 Sentence denotes Obviously it should be noted that treatment for anemia in a malarious area must be preceded by an effective anti-malarial therapy.
T327 24666-24789 Sentence denotes Notably, iron rich status promotes M2-like macrophage phenotype and negatively regulates M1 pro-inflammatory response [65].
T328 24790-24866 Sentence denotes On the other hand, iron overload causes impairment of immune function [140].
T329 24867-25019 Sentence denotes Iron excess increases the harmfulness of inflammation and the microorganisms themselves require iron as it can contribute to the growth of the pathogen.
T330 25020-25070 Sentence denotes RDA for iron reports a range of 8–18 mg/day [138].
T331 25072-25081 Sentence denotes Glutamine
T332 25082-25228 Sentence denotes The consumption of high biological value proteins is an essential component for a healthy diet and for the optimal production of antibodies [141].
T333 25229-25352 Sentence denotes Proteins, or amino acids, deficiency is known to impair immune function and increase susceptibility to infectious diseases.
T334 25353-25431 Sentence denotes In fact, some amino acids modulate both metabolism and immune functions [142].
T335 25432-25671 Sentence denotes Most reviews indicate an important role for amino acids in the immunity by regulating the activation of T lymphocytes, B lymphocytes, natural killer cells and macrophages; cellular redox state, gene expression and lymphocyte proliferation.
T336 25672-25864 Sentence denotes Evidence shows that the dietary integration of specific amino acids in humans with malnutrition and infectious diseases improves the immune status, thus reducing morbidity and mortality [141].
T337 25865-26058 Sentence denotes Glutamine is the most abundant and versatile amino acid present in the body and its level in the immune cells is similar to, or even greater than, glucose in both health and disease conditions.
T338 26059-26246 Sentence denotes The biological activities of this nutrient are also associated with the reduced cellular potential of oxygen, which mainly depends on the ratio between reduced/oxidized glutathione [143].
T339 26247-26434 Sentence denotes In addition, glutamine is an essential nutrient for lymphocyte proliferation and cytokine production, macrophage phagocytes plus secretory activities and bacterial killing of neutrophils.
T340 26435-26661 Sentence denotes In immune cells, glucose is mainly converted into lactate (glycolysis), while glutamine is converted into glutamate, aspartate and alanine undergoing a partial oxidation in carbon dioxide, in a process of glutaminolysis [142].
T341 26662-26747 Sentence denotes This unique conversion plays a crucial role in the effective functioning of immunity.
T342 26748-27086 Sentence denotes Glutamine is necessary for the expression of a variety of immune system genes [144], in particular through the activation of proteins, such as the ERK and JNK kinases which are involved in the activation of transcription factors, including JNK and AP-1, finally promoting the transcription of genes that participate in cell proliferation.
T343 27087-27276 Sentence denotes Besides, a sufficient level of glutamine is important to express the key markers of the cell surface of the lymphocytes and also various cytokines, for example, IL-6, IFN and TNF [143–145].
T344 27277-27603 Sentence denotes In healthy subjects with a balanced diet, glutamine supplementation does not increase the effectiveness of immune surveillance or prevent disease episodes, as reported by some reviews, but in some catabolic situations or in a low glutamine intake obtained from the diet, the amino acid supplementation could be required [142].
T345 27605-27613 Sentence denotes Arginine
T346 27614-27773 Sentence denotes The modulation of metabolism and immune functions, essential in the interaction and susceptibility to infectious diseases, is also regulated by arginine [146].
T347 27774-27903 Sentence denotes Arginine is a precursor for the synthesis of proteins, nitric oxide, urea, polyamines, proline, glutamate, creatine and agmatine.
T348 27904-28267 Sentence denotes The role and relationships between the pathways of arginine synthesis and catabolism are complex, due to the compartmentalized expression of various enzymes in different organs (e.g. liver, small intestine and kidney) and subcellular compartments (cytosol and mitochondria), as well as changes in gene expression in response to diet, hormones and cytokines [147].
T349 28268-28540 Sentence denotes As reported by several studies, arginine is the precursor of macrophages and it is now clear that arginine metabolism of immune cells is particularly involved in cancer, inflammation, infections, fibrotic diseases, pregnancy and the regulation of immune system [148, 149].
T350 28541-28657 Sentence denotes Macrophage arginine metabolism influences the outcome of immune responses in which innate immune cells are involved.
T351 28658-28818 Sentence denotes Arginine supplementation is reported to increase T lymphocyte response and Th cell numbers, suggesting a possible role in prolonged or repeated infection [150].
T352 28819-29078 Sentence denotes The importance of arginine metabolism as a new field of investigation includes that its depletion delays the growth of some types of tumours, while others report that its integration improves anticancer effects, probably by ameliorating immune function [150].
T353 29079-29223 Sentence denotes As discussed, vitamins E, C, D, zinc and selenium are important examples of nutrients that play a key role in supporting the immune system [65].
T354 29224-29265 Sentence denotes They can work individually or in synergy.
T355 29266-29387 Sentence denotes Furthermore, other dietary components are likely to play a role in modulating immunity, but have not yet been identified.
T356 29388-29464 Sentence denotes It is clear how nutritional deficiencies can compromise the immune response.
T357 29465-29641 Sentence denotes In addition, inflammation related to unhealthy eating habits has reached alarming proportions, particularly concerning chronic non-communicable diseases [100] (Tables 1 and 2).
T358 29642-29704 Sentence denotes Table 1 Dietary sources and immune function roles of nutrients
T359 29705-29756 Sentence denotes Nutrient Good dietary sources Immune function roles
T360 29757-30181 Sentence denotes Vitamin A Milk and cheese, eggs, liver, oily fish, fortified cereals, dark orange or green vegetables (e.g., carrots, sweet potatoes, pumpkin, squash, kale, spinach, broccoli), orange fruits (e.g., apricots, peaches, papaya, mango, cantaloupe melon), tomato juice Normal differentiation of epithelial tissue; retinoic acid ↑ T and B cells with gut-homing specificity and array T cells and IgA + cells into intestinal tissues
T361 30182-30347 Sentence denotes Supporting the gut barrier; carotenoids; ↑immunoregulatory actions including ↓ toxic effects of ROS and regulating membrane fluidity and gap-junctional communication
T362 30348-30449 Sentence denotes Regulates number and function of NK cells,↑ to phagocytic and oxidative burst activity of macrophages
T363 30450-30478 Sentence denotes Downregulates IFN production
T364 30479-30683 Sentence denotes Helps to regulate the production of IL-2 and the pro-inflammatory TNF-γ, ↑ microbial action of macrophages; involved in phagocytic and oxidative burst activity of macrophages activated during inflammation
T365 30684-30883 Sentence denotes Development and differentiation of Th1 and Th2 cells; ↑ TGF- β-dependent conversion of naïve T cells into regulatory T cells; plays a role in acquisition of mucosal-homing properties by T and B cells
T366 30884-31049 Sentence denotes Development and differentiation of Th 1 and Th2 cells; maintains normal antibody-mediated Th2 response by suppressing IL-12, TNF-α, and IFN-γ production of Th1 cells
T367 31050-31252 Sentence denotes Normal functioning of B cells, necessary for generation of antibody responses to antigen; required for B cell-mediated IgA antibody responses to bacterial polysaccharide antigens [62, 79–82, 85, 92, 95]
T368 31253-31561 Sentence denotes Vitamin C Oranges and orange juice, red and green peppers, strawberries, blackcurrants, kiwi, broccoli, brussels sprouts, potatoes ↑ collagen synthesis and protects cell membranes from damage caused by free radicals; ↑ keratinocyte differentiation; ↑ lipid synthesis; ↑ fibroblast proliferation and migration
T369 31562-31677 Sentence denotes Proliferation, function, and movement of neutrophils, monocytes and phagocytes; ↑ NK cell activities and chemotaxis
T370 31678-31732 Sentence denotes ↑ Phagocytosis and ROS generation; ↑ microbial killing
T371 31733-31818 Sentence denotes ↑ Apoptosis and clearance of spent neutrophils from sites of infection by macrophages
T372 31819-31872 Sentence denotes ↓ Extracellular trap (NET) formation, ↓ tissue damage
T373 31873-31935 Sentence denotes ↑ Antimicrobial effects; ↑ serum levels of complement proteins
T374 31936-32186 Sentence denotes Maintains redox homeostasis within cells and protects against ROS and RNS during oxidative burst; regenerates other important antioxidants, such as glutathione and vitamin E, to their active state; modulates cytokine production and ↓ histamine levels
T375 32187-32367 Sentence denotes Roles in production, differentiation, and proliferation of T cells, particularly cytotoxic T cells; ↑ proliferation of lymphocytes, ↑ generation of antibodies [79, 85, 92, 95, 120]
T376 32368-32812 Sentence denotes Vitamin D Oily fish, liver, eggs, fortified foods (spreads and some breakfast cereals) Regulates antimicrobial proteins (cathelicidin and β-defensin), modifying intestinal microbiota to a healthier composition and supporting the gut, as well as protecting the lungs against infection; ↑ tight junction protein expression, E-cadherin and connexion 43 in the gut; maintains renal epithelial barrier function; ↑ corneal epithelial barrier function
T377 32813-32987 Sentence denotes Vitamin D receptor found in, e.g., monocytes, macrophages, and DCs; ↑ differentiation of monocytes to macrophages; calcitriol ↑ movement and phagocytic ability of macrophages
T378 32988-33130 Sentence denotes Regulates antimicrobial protein expression (cathelicidin and defensin), which directly kill pathogens, especially bacteria; ↓ IFN-γ production
T379 33131-33338 Sentence denotes ↑ The oxidative burst potential of macrophages; increases superoxide synthesis; reduces the expression of pro-inflammatory cytokines and increases the expression of anti-inflammatory cytokines by macrophages
T380 33339-33723 Sentence denotes Homing of T cells to the skin; ↓ T-cell proliferation; inhibitory effects mainly in adaptive immunity (e.g., Th1-cell activity); stimulatory effects in innate immunity; ↓ the effector functions of T helper cells and cytotoxic T cells; ↑ the production of Tregs; inhibitory effect on the differentiation and maturation of the antigen-presenting DCs, and helps program DCs for tolerance
T381 33724-33756 Sentence denotes ↓ Antibody production by B cells
T382 33757-33863 Sentence denotes ↑ Antigen processing; role in the down-regulation of MHC-II) [64, 71, 79–81, 85, 95, 99, 104–106, 151–153]
T383 33864-34043 Sentence denotes Vitamin E Many vegetable oils, nuts and seeds, wheat germ (e.g., in cereals) Protects cell membranes from damage caused by free radicals and ↑ the integrity of epithelial barriers
T384 34044-34151 Sentence denotes ↑ NK cell cytotoxic activity; ↓ PGE2 production by macrophages (thus indirectly protecting T-cell function)
T385 34152-34379 Sentence denotes Important fat-soluble antioxidant that hinders the chain reaction induced by free radicals (chain-breaking effect) and protects cells against them; ↑ IL-2 production; ↓ production of PGE2 (indirectly protecting T-cell function)
T386 34380-34597 Sentence denotes ↑ Lymphocyte proliferation and T-cell-mediated functions; ↑ Th1 response; ↓ Th2 response; helps to form effective immune synapses between Th cells; ↑ proportion of antigen-experienced memory [64, 79, 82, 95, 112, 113]
T387 34598-34811 Sentence denotes Zinc Shellfish, meat, cheese, some grains and seeds, cereals, seeded or whole grain breads Helps maintain integrity of skin and mucosal membrane (e.g., cofactor for metalloenzymesrequired for cell membrane repair)
T388 34812-34992 Sentence denotes ↑ NK cell cytotoxic activity; central role in cellular growth and differentiation of immune cells that have a rapid differentiation and turnover; ↑ phagocytic capacity of monocytes
T389 34993-35050 Sentence denotes Involved in complement activity; role in IFN-γ production
T390 35051-35375 Sentence denotes Anti-inflammatory agent; helps to modulate cytokine release by dampening the development of pro-inflammatory Th17 and Th9 cells and influencing the generation of cytokines such as IL-2, IL-6, and TNF; has antioxidant effects that protect against ROS and reactive nitrogen species; influences activity of antioxidant proteins
T391 35376-35705 Sentence denotes ↑ Proliferation of cytotoxic T cells; involved in Th1 cytokine production and thus supports Th1 response; essential for intracellular binding of tyrosine kinase to T cell receptors, required for T cell development, differentiation, and activation; ↑ development of Treg cells and is thus important in maintaining immune tolerance
T392 35706-35912 Sentence denotes Involved in antibody production, particularly IgG; involved in antibody response; important in maintaining immune tolerance (i.e., the ability to recognize “self” from “non-self”) [64, 82, 95, 116, 118–121]
T393 35913-36001 Sentence denotes Selenium Fish, shellfish, meat, eggs, some nuts especially brazil nuts ↑ IFN-γproduction
T394 36002-36104 Sentence denotes Selenoproteins important for antioxidant host defense system, affecting leukocyte and NK cell function
T395 36105-36264 Sentence denotes Essential for function of selenoproteins that act as redox regulators and cellular antioxidants, potentially counteracting ROS produced during oxidative stress
T396 36265-36318 Sentence denotes Roles in differentiation and proliferation of T cells
T397 36319-36384 Sentence denotes ↑ Th cell counts and to maintain antibody levels [82, 85, 92, 95]
T398 36385-36607 Sentence denotes Iron Meat, liver, beans, nuts, dried fruit (e.g., apricots), wholegrains (e.g., brown rice), fortified cereals, most dark green leafy vegetables (spinach, kale) Essential for differentiation and growth of epithelial tissue
T399 36608-36963 Sentence denotes Forms highly-toxic hydroxyl radicals, thus involved in killing of bacteria by neutrophils; component of enzymes critical for functioning of immune cells (e.g., ribonucleotide reductase involved in DNA synthesis); involved in regulation of cytokine production and action; ↑ M2-like macrophage phenotype and negatively regulates M1 pro-inflammatory response
T400 36964-36988 Sentence denotes Role in IFN-γ production
T401 36989-37132 Sentence denotes Involved in regulation of cytokine production and action; required for generation of pathogen-killing ROS by neutrophils during oxidative burst
T402 37133-37274 Sentence denotes Important in differentiation and proliferation of T cells; helps to regulate ratio between T helper cells and cytotoxic T cells [85, 95, 138]
T403 37275-37493 Sentence denotes Long chain omega-3 fatty acids (EPA and DHA) Oilyfish Anti-inflammatory and antioxidant properties when enzymatically converted to specialized pro-resolving mediators (SPMs) known as resolvins, protectins, and maresins
T404 37494-37571 Sentence denotes ↑ Immune system, by helping to resolve the inflammatory response [63, 66, 67]
T405 37572-37653 Sentence denotes Table 2 Nutrient’s supplementation suggested in support of respiratory infections
T406 37654-37737 Sentence denotes Nutrient Recommended supplementation suggested in support of respiratory infections
T407 37738-37772 Sentence denotes Omega 3 fatty acids 2–4 g/day [68]
T408 37773-37805 Sentence denotes Vitamin D 20,000–50,000 IU [154]
T409 37806-37832 Sentence denotes Vitamin E 135 mg/day [114]
T410 37833-37855 Sentence denotes Zinc 30–50 mg/day [98]
T411 37856-37884 Sentence denotes Selenium 25–100 μg/day [130]
T412 37885-37930 Sentence denotes Arginine and glutamine 25–35 g/day [142, 146]
T413 37931-37955 Sentence denotes Vitamin C 1–2 g/day [98]
T414 37956-37985 Sentence denotes Vitamin A 900–700 µg/day [91]
T415 37986-38008 Sentence denotes Iron 8–18 mg/day [138]
T416 38010-38064 Sentence denotes The role of gut microbiota in COVID-19 immunonutrition
T417 38065-38147 Sentence denotes The human intestine hosts a complex bacterial community called the gut microbiota.
T418 38148-38267 Sentence denotes The microbiota is specific to each individual despite the existence of several bacterial species shared by most adults.
T419 38268-38337 Sentence denotes Scientific studies reveal its influence on human health and diseases.
T420 38338-38542 Sentence denotes In particular they have shown that the intestinal microbiota can play a causal role in the development of obesity and associated metabolic disorders, leading to the identification of different mechanisms.
T421 38543-38775 Sentence denotes In humans, differences are observed in the composition of the microbiota, in the functional genes and in the metabolic activities between obese and lean individuals, that suggest a contribution of the microbiota to these phenotypes.
T422 38776-38990 Sentence denotes Finally, the evidence linking intestinal bacteria to host metabolism could allow the development of new therapeutic strategies based on the modulation of the intestinal microbiota to treat or prevent obesity [155].
T423 38991-39116 Sentence denotes Microbiota plays a crucial role in the maturation, development and functions of both innate and adaptive immune system [156].
T424 39117-39260 Sentence denotes The gut microbiota has been shown to affect lung health through a vital crosstalk between gut microbiota and lungs, called the “gut-lung axis”.
T425 39261-39489 Sentence denotes This axis communicates through a bi-directional pathway in which endotoxins, or microbial metabolites, may affect the lung through the blood and when inflammation occurs in the lung, this, in turn, can affect the gut microbiota.
T426 39490-39612 Sentence denotes The immunological health of the gut, primarily mediated by the microbiota, influences lung health via the “gut-lung axis”.
T427 39613-39786 Sentence denotes In addition, microbial communities inhabiting the mucosal surfaces of the respiratory tract also contribute towards host defense against viral respiratory infections (VRIs).
T428 39787-39917 Sentence denotes Acute VRIs are associated with microbial dysbiosis in these communities, thus acting the optimal functioning of the immune system.
T429 39918-40158 Sentence denotes Alterations in the microbiota during influenza virus infection contributes to the pathogenesis of secondary bacterial infections, thus increasing the severity of the clinical course in the absence of appropriate immune responses [157, 158].
T430 40159-40373 Sentence denotes It is also known that alterations of the immune functions associated with chronic inflammation and related metabolic dysfunctions lead to a compromise of innate and acquired immune functions in the host [159, 160].
T431 40374-40556 Sentence denotes Moreover, chronic inflammation and the use of antibiotics are known to accompany disorders in the gut microbiota, resulting in dysbiosis and aggravation of immune dysfunctions [161].
T432 40557-40839 Sentence denotes In addition, the prevalence of comorbid conditions (including chronic lung disease, diabetes, hypertension and cardiovascular diseases) and old age predispose to infection, the development of ARDS and pneumonia, factors already observed for other infections such as influenza [162].
T433 40840-40955 Sentence denotes This point raises an interesting possibility that the new SARS-Cov-2 may also have an impact on the gut microbiota.
T434 40956-41089 Sentence denotes Indeed, several studies have shown that respiratory infections are associated with a change in the composition of the gut microbiota.
T435 41090-41239 Sentence denotes Numerous experimental and clinical observations have suggested that the gut microbiota plays a key role in the pathogenesis of sepsis and ARDS [163].
T436 41240-41463 Sentence denotes Moreover, it is known that the signals derived from the intestinal microbiota tune the cells of the immune system for pro and anti-inflammatory responses which thus influence the susceptibility to various diseases (Fig. 2).
T437 41464-41569 Sentence denotes Fig. 2 Graphical representation of immune homeostasis disequilibrium during SARS-Coronavirus 2 infection.
T438 41570-41696 Sentence denotes ARDS: acute respiratory distress syndrome; T lymphocyte; IL: interleukin; Th: helper T lymphocyte; TNF: tumour necrosis factor
T439 41697-41790 Sentence denotes It is also known that respiratory virus infection causes perturbations in the gut microbiota.
T440 41791-41916 Sentence denotes Diet, environmental factors and genetics play an important role in shaping gut microbiota which can influence immunity [164].
T441 41917-42022 Sentence denotes There is growing evidence that supports the roles of the gut microbiota and diet to shape immunity [165].
T442 42023-42193 Sentence denotes Modulating the composition and metabolic capacity of the microbiome for specific dietary components is a promising strategy for influencing immune responses against VRIs.
T443 42194-42414 Sentence denotes Functional food components including probiotics, prebiotics and other bioactive ingredients of plant origin have been associated with immune benefits, mainly via microbiota modulation and impact on oxidative stress [65].
T444 42415-42641 Sentence denotes Several papers, regarding body composition, evaluated the correlation between fat mass and disease risk and then identified a new frontier of gut microbiota composition in the bodyweight decrease and anti-inflammatory effects.
T445 42642-42993 Sentence denotes As shown, the prevention of cardiometabolic diseases, considering the relationship with obesity, may be possible reducing the inflammatory state, acting on the gut-microbiota and on the intestinal permeability improving the health of the intestinal flora, with 4P medicine and treatment with probiotics, prebiotics, postbiotics, and polyphenols [166].
T446 42994-43178 Sentence denotes Prebiotic from fruits and vegetables is well-established to modulate the gut microbiota and numerous benefits have been reported in chronic inflammatory and metabolic conditions [167].
T447 43179-43357 Sentence denotes In fact, dietary fibers are a good source of accessible carbohydrates for microbiota then prebiotics have been studied in the context of modification of the human gut microbiota.
T448 43358-43529 Sentence denotes The compounds such as inulin, polydextrose, maize fiber have been shown to improve the immunity, gut diversity, digestion in humans and especially in elderly people [164].
T449 43530-43678 Sentence denotes Moreover, increased dietary fiber consumption is linked to reduced mortality rates in respiratory-related diseases and improved lung function [162].
T450 43679-43813 Sentence denotes Thus, plant-based diets, functional foods, and supplements present a promising strategy for protecting against respiratory infections.
T451 43814-43971 Sentence denotes Prebiotics lead the influence of microbiota composition and undergo microbial fermentation to produce SCFAs, such as butyrate, acetate, and propionate [168].
T452 43972-44231 Sentence denotes Overall, it is apparent that diet and personalized nutritional interventions acting in modulation of gut microbiota especially to control dysbiosis state and to some extent even lung microbiota can influence health status such as immunity conditions (Fig. 3).
T453 44232-44320 Sentence denotes Fig. 3 Graphical representation of personalized nutritional intervention during COVID-19
T454 44321-44547 Sentence denotes In addition, probiotics which are generally defined as “live microorganisms, which, when administered in adequate amounts, confer a health benefit on the host” have been shown to have profound effect on the health of the host.
T455 44548-44852 Sentence denotes In the intestine, the probiotics mainly refer to the genera Lactobacillus and Bifidobacterium and include many different strains such as L. johnsonii, L. fermentum, L. reuteri, L. paracasei, L. rhamnosus, L. acidophilus, L. plantarum, B. longum, B. breve, B. bifidum, and B. animalis subsp. lactis [169].
T456 44853-44939 Sentence denotes Fermented foods such as cultured milk products and yoghurt are enriched in probiotics.
T457 44940-45119 Sentence denotes They have shown good results in modulating inflammatory conditions as well as regulating innate immunity using toll-like receptors and the corresponding signalling pathways [170].
T458 45120-45316 Sentence denotes The capacity of probiotics to induce immunomodulation could be mediated either directly through interaction with immune cells or indirectly by supporting the challenged commensal microbiota [171].
T459 45317-45669 Sentence denotes Ingested probiotics with diet or through supplementation stimulate the immune system and initiate a complex of signals mediated by the whole bacteria, they then interact with intestinal epithelial cells also with immune cells associated with the lamina propria or other microbial PRRs and trigger the production of an array of cytokines and chemokines.
T460 45670-45804 Sentence denotes These molecules then interact with other immune cells through other pathways, leading to the activation of the mucosal immune systems.
T461 45805-45926 Sentence denotes As reported by many reviews specific probiotics have been demonstrated to enhance Th1 and regulatory Treg function [162].
T462 45927-46103 Sentence denotes It is clear that probiotics have an important role in the maintenance of immunologic equilibrium in the gastrointestinal tract through the direct interaction with immune cells.
T463 46104-46243 Sentence denotes Probiotic effectiveness can be species-, dose-, and disease-specific, and the duration of therapy depends on the clinical indication [170].
T464 46244-46489 Sentence denotes Additionally, phytochemicals including vitamins, micronutrients, and polyphenols present in fruits and vegetables have been shown a considerable importance in nutritional strategies for addressing the severity of viral respiratory diseases [65].
T465 46490-46609 Sentence denotes Some polyphenols influence microbiota composition and also have antioxidant, anti-inflammatory, and anti-viral effects.
T466 46610-46818 Sentence denotes The antiviral effect of polyphenols have been demonstrated to be mediated either by direct inhibitory effects on virus replication or through the induction of immunomodulatory and antioxidant responses [172].
T467 46819-46960 Sentence denotes In fact, oxidative stress has been implicated in lung tissue injury and epithelial barrier dysfunction in acute respiratory viral infections.
T468 46961-47091 Sentence denotes Dietary polyphenols are present in foods such as vegetables, fruits, cereals, tea, coffee, dark chocolate, cocoa powder, and wine.
T469 47092-47217 Sentence denotes The main groups of dietary polyphenols consist in phenolic acids, flavonoids, tannins, stilbenes and diferuloylmethane [173].
T470 47218-47392 Sentence denotes Many evidences revealed the excellent immunomodulatory effects of epigallocatechin-3-gallate (EGCG), abundant in green tea on both innate and adaptive immune responses [174].
T471 47393-47545 Sentence denotes Finally, in this context there is an important role explained by postbiotics (also known as metabiotic, biogenic, or metabolite cell-free supernatants).
T472 47546-47713 Sentence denotes Postbiotics are products or metabolic byproducts secreted by live bacteria or released after bacterial lysis and they provide physiological benefits to the host [175].
T473 47714-47900 Sentence denotes There are multiple types of postbiotics with varied structures, such as Short Chain Fatty Acids (SCFAs), peptides, enzymes, teichoic acids, exo- and endo-polysaccharides, vitamins [176].
T474 47901-48079 Sentence denotes A protective role of postbiotics like SCFAs has been found in the immune system modulation; particularly in regulation of neutrophil migration in acute inflammation in the colon.
T475 48080-48327 Sentence denotes The benefits of microbially-fermented SCFAs are suggested to be mediated through the direct actions of G-protein-coupled receptors (GPRs) expressed on the gut epithelium, adipose tissues and immune cells, including monocytes and neutrophils [177].
T476 48328-48457 Sentence denotes Gut-derived SCFAs have been shown to influence the functions of innate immune cells as well as impact acquired immune components.
T477 48458-48739 Sentence denotes Studying microbiota and therefore the human immune system and its dysregulation, or controlling the effects of postbiotics in the symbiotic status represents an important opportunity to develop new drugs, and combining probiotic supplements, with vaccines and immunotherapies [16].