Immunomodulatory Role of Nutrients: How Can Pulmonary Dysfunctions Improve?

The guardians of pulmonary harmony: alveolar macrophages orchestrating the symphony of lung inflammation and tissue homeostasis

Recent breakthroughs in single-cell sequencing, advancements in cellular and tissue imaging techniques, innovations in cell lineage tracing, and insights into the epigenome collectively illuminate the enigmatic landscape of alveolar macrophages in the lung under homeostasis and disease conditions. Our current knowledge reveals the cellular and functional diversity of alveolar macrophages within the respiratory system, emphasising their remarkable adaptability. By synthesising insights from classical cell and developmental biology studies, we provide a comprehensive perspective on alveolar macrophage functional plasticity. This includes an examination of their ontology-related features, their role in maintaining tissue homeostasis under steady-state conditions and the distinct contribution of bone marrow-derived macrophages (BMDMs) in promoting tissue regeneration and restoring respiratory system homeostasis in response to injuries. Elucidating the signalling pathways within inflammatory conditions, the impact of various triggers on tissue-resident alveolar macrophages (TR-AMs), as well as the recruitment and polarisation of macrophages originating from the bone marrow, presents an opportunity to propose innovative therapeutic approaches aimed at modulating the equilibrium between phenotypes to induce programmes associated with a pro-regenerative or homeostasis phenotype of BMDMs or TR-AMs. This, in turn, can lead to the amelioration of disease outcomes and the attenuation of detrimental inflammation. This review comprehensively addresses the pivotal role of macrophages in the orchestration of inflammation and resolution phases after lung injury, as well as ageing-related shifts and the influence of clonal haematopoiesis of indeterminate potential mutations on alveolar macrophages, exploring altered signalling pathways and transcriptional profiles, with implications for respiratory homeostasis.

Improvement of Lung Function by Micronutrient Supplementation in Patients with COPD: A Systematic Review and Meta-Analysis

BACKGROUND

A healthy, well-balanced diet plays an essential role in respiratory diseases. Since micronutrient deficiency is relatively common in patients with chronic obstructive pulmonary disease (COPD), micronutrient supplementation might have the beneficial health effects in those patients. This systematic review and meta-analysis aimed to demonstrate the impact of micronutrient supplementation on the lung function of patients with COPD.

METHODS

The PubMed, Cochrane Library, and Web of Science databases were searched from their corresponding creation until February 2024. Search terms included 'chronic obstructive pulmonary disease', 'COPD', 'micronutrients', 'dietary supplements', 'vitamins', 'minerals', and 'randomized controlled trials'. Meta-analysis was performed to evaluate the effects of micronutrient supplementation alone or complex on lung function in patients with COPD.

RESULTS

A total of 43 RCTs fulfilled the inclusion criteria of this study. Meta-analysis revealed that vitamin D supplementation could significantly improve FEV1% (WMDdifferences between baseline and post-intervention (de): 6.39, 95% CI: 4.59, 8.18, p < 0.01; WMDpost-intervention indicators (af): 7.55, 95% CI: 5.86, 9.24, p < 0.01) and FEV1/FVC% (WMDde: 6.88, 95%CI: 2.11, 11.65, WMDaf: 7.64, 95% CI: 3.18, 12.10, p < 0.001), decrease the odds of acute exacerbations, and improve the level of T-cell subsets, including CD3+%, CD4+%, CD8+%, and CD4+/CD8+% (all p < 0.01). The effects of compound nutrients intervention were effective in improving FEV1% (WMDde: 8.38, 95%CI: 1.89, 14.87, WMDaf: 7.07, 95%CI: -0.34, 14.48) and FEV1/FVC% (WMDde: 7.58, 95% CI: 4.86, 10.29, WMDaf: 6.00, 95% CI: 3.19, 8.81). However, vitamin C and vitamin E supplementation alone had no significant effects on lung function (p > 0.05).

CONCLUSIONS

Micronutrient supplementation, such as vitamin D alone and compound nutrients, has improved effect on the lung function of patients with COPD. Therefore, proper supplementation with micronutrients would be beneficial to stabilize the condition and restore ventilation function for COPD patients.

Vitamin D Supplementation in Neonatal and Infant MIS-C Following COVID-19 Infection

To date, the SARS-CoV-2 pandemic still represents a great clinical challenge worldwide, and effective anti-COVID-19 drugs are limited. For this reason, nutritional supplements have been investigated as adjuvant therapeutic approaches in disease management. Among such supplements, vitamin D has gained great interest, due to its immunomodulatory and anti-inflammatory actions both in adult and pediatric populations. Even if there is conflicting evidence about its prevention and/or mitigation effectiveness in SARS-CoV-2 infection, several studies demonstrated a strict correlation between hypovitaminosis D and disease severity in acute COVID-19 and MIS-C (multisystem inflammatory syndrome in children). This narrative review offers a resume of the state of the art about vitamin D's role in immunity and its clinical use in the context of the current pandemic, specially focusing on pediatric manifestations and MIS-C. It seems biologically reasonable that interventions aimed at normalizing circulating vitamin D levels could be beneficial. To help clinicians in establishing the correct prophylaxis and/or supportive therapy with vitamin D, well-designed and adequately statistically powered clinical trials involving both adult and pediatric populations are needed. Moreover, this review will also discuss the few other nutraceuticals evaluated in this context.

The Association Between Dietary Magnesium Intake and Pulmonary Function: Recent Fndings from NHANES 2007-2012

This article aims to study the correlation between dietary magnesium intake and pulmonary function, utilizing data from the National Health and Nutrition Examination Survey (NHANES) database. This cross-sectional study examined representative samples of adults from the USA (n = 818; NHANES 2007-2012) to explore the correlation between magnesium intake and pulmonary function. We obtained the average magnesium intake over 2 days, as well as measured pulmonary function parameters, including forced expiratory volume in the first second (FEV1), forced vital capacity (FVC), FEV1/FVC, peak expiratory flow rate (PEF), and forced expiratory flow between 25 and 75% of FVC (FEF25-75%). Weighted multivariable linear regression was used to investigate the relationship between magnesium intake and pulmonary function. Additionally, subgroup analyses, interaction tests, and sensitivity analyses were conducted. Weighted multiple linear regression models revealed a significant positive correlation between magnesium and pulmonary function, even after adjusting for all included confounding variables. When we categorized magnesium intake into tertiles, we found that participants in the highest tertile of magnesium intake had significantly higher values for FVC (β: 898.54, 95%CI: 211.82-1585.25), FEV1 (β: 858.16, 95%CI: 212.41-1503.91), FEV1/FVC (β: 0.024, 95%CI: 0.004-0.044), PEF (β: 1324.52, 95%CI: 481.71-2167.33), and FEF25-75% (β: 831.39, 95%CI: 84.93-1577.84). Upon stratifying the data by age and sex, it was observed that this positive correlation was particularly pronounced among men aged 40-79. At the same time, the stability of the results was further confirmed by sensitivity analyses. This study suggested that dietary magnesium intake may improve pulmonary function.

Effect of dietary interventions on markers of type 2 inflammation in asthma: A systematic review

INTRODUCTION

Type 2 (T2) inflammation is a key mechanism in the pathophysiology of asthma. Diet may have immunomodulatory effects, and a role for diet in T2 inflammation has been suggested in the literature. Indeed, diet and food allergies play a role in children with atopic asthma, but less is known about diet in relation to adult asthma, which is often non-atopic.

OBJECTIVE

To review the effect of dietary interventions on markers of T2 inflammation in adults with asthma.

METHODS

The databases PubMed, Embase, Cochrane Library, and CINAHL were searched for eligible studies until December 2022. We included studies of all types of foods, nutrients, diets or supplements, either as an exposure or as an intervention, in adults and adolescents with asthma. Outcomes of interest included the T2 biomarkers FeNO, eosinophils, IL-4, IL-5, IL-13, eosinophil cationic protein and eosinophil peroxidase. The methodological quality of eligible studies was systematically evaluated, and the results were summarised according to dietary clusters.

RESULTS

The systematic search identified studies on the dietary clusters antioxidants (n = 14), fatty acids, (n = 14), Mediterranean-style diets (n = 5), phytotherapy (n = 7), prebiotics & probiotics (n = 8), vitamin D (n = 7), and other dietary factors (n = 5). Studies within the phytotherapy and omega-3 poly-unsaturated fatty acids (PUFA) clusters showed possible improvements in T2 inflammation. Furthermore, we found little evidence for an effect of antioxidants, prebiotics & probiotics, and Mediterranean-style diets on T2 inflammation. However, heterogeneity in study protocols, methodological shortcomings and limited power of almost all studies make it difficult to fully determine the impact of different dietary approaches on T2 inflammation in asthma.

CONCLUSIONS

Overall, the current evidence does not support a specific dietary intervention to improve T2 inflammation in asthma. Interventions involving phytotherapy and omega-3 PUFA currently have the best evidence and warrant further evaluation in well-designed and adequately powered studies, while taking into account T2-high phenotypes of asthma.

Dietary antioxidants and flavonoids intake, and their association with inflammation and oxidative stress parameters in asthmatic women: a case-control study

Asthma is more prevalent and severe in women, especially after puberty. Studies suggest a potential link between dietary antioxidants, inflammation, and oxidative stress. This study aimed to compare the dietary intake of antioxidants in asthmatic and healthy women, evaluating their potential associations with inflammation and oxidative stress. This study analyzed 30 asthmatic and 30 healthy women's lung function, anthropometry, biochemical parameters, and dietary antioxidant intake using a 161-itemized semi-quantitative food frequency questionnaire. Additionally, the study explored connections between serum inflammatory markers and oxidative stress indicators in relation to dietary intake of antioxidant nutrients and flavonoids. Asthmatic women exhibited higher serum IL-6 levels and lower total antioxidant status compared to healthy controls. Nevertheless, no significant differences were observed in dietary antioxidant micronutrient intake. Healthy controls demonstrated a notably higher intake of anthocyanidins compared to asthmatic women. Furthermore, the study identified a negative correlation between flavonol intake and serum total oxidant status, as well as between flavan-3-ols intake and serum oxidative stress index. Dietary differences in flavonoid and flavonoid-rich foods intake among asthmatic women may affect their serum IL-6 levels and oxidative stress. Promoting a diverse diet rich in flavonoids could benefit women with asthma by mitigating inflammation and oxidative stress.

The Associations Between Serum Vitamins and Carotenoids with Chronic Obstructive Pulmonary Disease: Results from the NHANES

Purpose

Vitamins and carotenoids are essential in preventing and treating chronic obstructive pulmonary disease (COPD). This study investigated the associations between serum vitamins, carotenoids, and COPD in adults aged ≥ 40 years in the United States.

Methods

We selected 3487 participants aged ≥40 from the NHANES (2017-2018) and used demographic analysis, sensitivity tests, and different weighted multivariate regression models to investigate the relationship between serum vitamins, carotenoids, and COPD.

Results

Subjects in the highest tertile of serum vitamin C, vitamin E (α-tocopherol), α-carotene, trans-β-carotene, and cis-β-carotene had a 50%, 35%, 51%, 54%, and 51% lower risk of COPD than those in the lowest tertile (P for trend: P=0.0005, <0.0001, 0.0054, 0.0066, and 0.0049). Unfortunately, no significant correlation was found for serum vitamin D levels.

Conclusion

Our analysis of nationally representative data from 3487 participants showed that serum levels of vitamin C, vitamin E (α-tocopherol), α-carotene, and β-carotene were negatively associated with the incidence of COPD in adults over 40 years of age in the US The findings highlighted the importance of antioxidant vitamins and carotenoids in respiratory health, while the data showed no significant correlation between vitamin D (25-OHD) and the incidence of COPD.

Dietary Inflammatory Index and Clinical Outcome Measures in Adults With Moderate-to-Severe Asthma

BACKGROUND

Diet is increasingly recognized as a modifiable factor in lung health, predominantly due to the immunomodulatory effects of nutrients. The Dietary Inflammatory Index (DII) is a score developed to express the inflammatory potential of a diet.

OBJECTIVE

We aimed to assess the association of the DII and food groups, with clinical, functional, and inflammatory asthma outcomes in adults with asthma.

METHODS

Patients with moderate-to-severe asthma were included in this cross-sectional study between June 2019 and October 2021, and completed a 3-day food diary, to calculate the DII and intake of food groups (ie, fruits, whole grains, processed meats, and sugar-sweetened beverages). Functional outcomes included pulmonary function tests and the 6-minute walking distance, whereas clinical outcomes were assessed using questionnaires on asthma control, quality of life, and health care utilization. Inflammatory markers were exhaled nitric oxide and blood leukocytes, eosinophils, and IL-6. Multivariable regression analyses were used to examine the association of DII and food groups with asthma outcomes.

RESULTS

A total of 109 patients participated (35% male, mean ± standard deviation age 51.8 ± 14.2 years, body mass index 27.4 ± 5.3 kg/m2). Overall, 62% had a DII score >0, indicating a proinflammatory diet, which was not related to asthma severity. A more proinflammatory diet was consistently associated with lower forced vital capacity (%pred), but inconsistent results were observed with respect to airway obstruction. Neither the DII nor food groups were associated with clinical outcomes. Except for higher levels of exhaled nitric oxide in relation to an anti-inflammatory diet, we found no associations between inflammatory markers and the DII.

CONCLUSION

Results from this cross-sectional study among patients with moderate-to-severe asthma do not support the hypothesis that a proinflammatory diet is associated with worse asthma outcomes, although limitations in study design and dietary intake estimation should be considered. Future well-designed experimental studies are needed to assess whether targeting the inflammatory potential of diet could lead to better outcomes in adults with asthma.

The Role of Diet and Nutrition in Allergic Diseases

Allergic diseases are a set of chronic inflammatory disorders of lung, skin, and nose epithelium characterized by aberrant IgE and Th2 cytokine-mediated immune responses to exposed allergens. The prevalence of allergic diseases, including asthma, allergic rhinitis, and atopic dermatitis, has increased dramatically worldwide in the past several decades. Evidence suggests that diet and nutrition play a key role in the development and severity of allergic diseases. Dietary components can differentially regulate allergic inflammation pathways through host and gut microbiota-derived metabolites, therefore influencing allergy outcomes in positive or negative ways. A broad range of nutrients and dietary components (vitamins A, D, and E, minerals Zn, Iron, and Se, dietary fiber, fatty acids, and phytochemicals) are found to be effective in the prevention or treatment of allergic diseases through the suppression of type 2 inflammation. This paper aims to review recent advances in the role of diet and nutrition in the etiology of allergies, nutritional regulation of allergic inflammation, and clinical findings about nutrient supplementation in treating allergic diseases. The current literature suggests the potential efficacy of plant-based diets in reducing allergic symptoms. Further clinical trials are warranted to examine the potential beneficial effects of plant-based diets and anti-allergic nutrients in the prevention and management of allergic diseases.

Distinguishing science from pseudoscience in commercial respiratory interventions: an evidence-based guide for health and exercise professionals

Respiratory function has become a global health priority. Not only is chronic respiratory disease a leading cause of worldwide morbidity and mortality, but the COVID-19 pandemic has heightened attention on respiratory health and the means of enhancing it. Subsequently, and inevitably, the respiratory system has become a target of the multi-trillion-dollar health and wellness industry. Numerous commercial, respiratory-related interventions are now coupled to therapeutic and/or ergogenic claims that vary in their plausibility: from the reasonable to the absurd. Moreover, legitimate and illegitimate claims are often conflated in a wellness space that lacks regulation. The abundance of interventions, the range of potential therapeutic targets in the respiratory system, and the wealth of research that varies in quality, all confound the ability for health and exercise professionals to make informed risk-to-benefit assessments with their patients and clients. This review focuses on numerous commercial interventions that purport to improve respiratory health, including nasal dilators, nasal breathing, and systematized breathing interventions (such as pursed-lips breathing), respiratory muscle training, canned oxygen, nutritional supplements, and inhaled L-menthol. For each intervention we describe the premise, examine the plausibility, and systematically contrast commercial claims against the published literature. The overarching aim is to assist health and exercise professionals to distinguish science from pseudoscience and make pragmatic and safe risk-to-benefit decisions.

The Effectiveness of Supplementation with Key Vitamins, Minerals, Antioxidants and Specific Nutritional Supplements in COPD-A Review

Currently, an increasing amount of evidence supports the notion that vitamins C, D and E, carotenoids, and omega-3 fatty acids may protect against the progression of chronic respiratory diseases. Although chronic obstructive pulmonary disease (COPD) primarily affects the lung, it is often accompanied by extrapulmonary manifestations such as weight loss and malnutrition, skeletal muscle dysfunction, and an excess of harmful oxidants, which can lead to a decline in quality of life and possible death. Recently, the role of various vitamins, minerals, and antioxidants in mitigating the effects of environmental pollution and smoking has received significant attention. Therefore, this review evaluates the most relevant and up-to-date evidence on this topic. We conducted a literature review between 15 May 2018 and 15 May 2023, using the electronic database PubMed. Our search keywords included COPD, chronic obstructive pulmonary disease, FEV₁, supplementation: vitamin A, vitamin D, vitamin E, vitamin C, vitamin B, omega-3, minerals, antioxidants, specific nutrient supplementations, clinical trials, and randomized controlled trials (RCTs). We focused on studies that measured the serum levels of vitamins, as these are a more objective measure than patient self-reports. Our findings suggest that the role of appropriate dietary supplements needs to be reconsidered for individuals who are predisposed to or at risk of these conditions.

Importance of Magnesium Status in COVID-19

A large amount of published research points to the interesting concept (hypothesis) that magnesium (Mg) status may have relevance for the outcome of COVID-19 and that Mg could be protective during the COVID disease course. As an essential element, Mg plays basic biochemical, cellular, and physiological roles required for cardiovascular, immunological, respiratory, and neurological functions. Both low serum and dietary Mg have been associated with the severity of COVID-19 outcomes, including mortality; both are also associated with COVID-19 risk factors such as older age, obesity, type 2 diabetes, kidney disease, cardiovascular disease, hypertension, and asthma. In addition, populations with high rates of COVID-19 mortality and hospitalization tend to consume diets high in modern processed foods, which are generally low in Mg. In this review, we review the research to describe and consider the possible impact of Mg and Mg status on COVID-19 showing that (1) serum Mg between 2.19 and 2.26 mg/dL and dietary Mg intakes > 329 mg/day could be protective during the disease course and (2) inhaled Mg may improve oxygenation of hypoxic COVID-19 patients. In spite of such promise, oral Mg for COVID-19 has thus far been studied only in combination with other nutrients. Mg deficiency is involved in the occurrence and aggravation of neuropsychiatric complications of COVID-19, including memory loss, cognition, loss of taste and smell, ataxia, confusion, dizziness, and headache. Potential of zinc and/or Mg as useful for increasing drug therapy effectiveness or reducing adverse effect of anti-COVID-19 drugs is reviewed. Oral Mg trials of patients with COVID-19 are warranted.

The Role of Vitamins in the Pathogenesis of Asthma

Vitamins play a crucial role in the proper functioning of organisms. Disturbances of their levels, seen as deficiency or excess, enhance the development of various diseases, including those of the cardiovascular, immune, or respiratory systems. The present paper aims to summarize the role of vitamins in one of the most common diseases of the respiratory system, asthma. This narrative review describes the influence of vitamins on asthma and its main symptoms such as bronchial hyperreactivity, airway inflammation, oxidative stress, and airway remodeling, as well as the correlation between vitamin intake and levels and the risk of asthma in both pre- and postnatal life.

Oxidative Stress Induced by Selenium Deficiency Contributes to Inflammation, Apoptosis and Necroptosis in the Lungs of Calves

Selenium is an essential trace element for health that can only be obtained through food. However, the pathological processes of selenium deficiency in cattle have received little attention. This study investigated the effects of selenium deficiency on oxidative stress, apoptosis, inflammation, and necroptosis in the lungs of weaning calves compared with healthy calves as controls. The lung selenium content and the expression of 11 selenoproteins mRNA in selenium-deficient calves were substantially reduced compared with the controls. Pathological results showed engorged alveolar capillaries, thickened alveolar septa, and diffuse interstitial inflammation throughout the alveolar septa. The levels of GSH and T-AOC, as well as the CAT, SOD, and TrxR activities, were significantly decreased compared with healthy calves. MDA and H₂O₂ were significantly elevated. Meanwhile, the apoptosis activation in the Se-D group was validated. Next, in the Se-D group, several pro-inflammatory cytokines showed higher expression. Further research revealed that the lungs in the Se-D group experienced inflammation via hyperactive NF-κB and MAPK pathways. The high level of expression of c-FLIP, MLKL, RIPK1, and RIPK3 indicated that necroptosis also causes lung damage during selenium deficiency.

Ultra-processed foods and allergic symptoms among children and adults in the United States: A population-based analysis of NHANES 2005-2006

Design

There is a strong correlation between dietary intake and allergic diseases. Ultra-processed foods (UPFs) are gradually becoming dominant worldwide and causing health problems for children and adults. We hope to determine whether links exist between UPFs and allergic symptoms.

Methods

We investigated data from 2,736 children (16-19 years) and 4,256 adults (≥20 years) from the National Health and Nutritional Examination Survey (NHANES) 2005-2006. The associations between the mean UPFs contribution to total energy intake and all allergic symptoms (IgE, current asthma, allergy, rash, sneeze, wheeze, eczema, and hay fever) were estimated by weighted multivariate logistic regression.

Results

Logistic regression analysis showed UFPs were negatively associated with IgE levels in children. Those with higher quartiles had a reduced risk from 16% (OR, 0.84, 95%CI, 0.55 to 1.28) to 34% (OR, 0.66, 95%CI, 0.49 to 0.89), p for trend = 0.006. UPFs were also positively related to current asthma in children with an increased risk of 11% (OR, 1.11, 95%CI, 0.79 to 1.56) to 76% (OR, 1.76, 95%CI, 1.10 to 2.82), p for trend = 0.0393. UPFs were also associated with eczema in girls. But there was no association observed between UPFs and allergic symptoms in adults.

Conclusion

Our results suggested that UPFs assessed by the NOVA system were associated with IgE, current asthma in children, and eczema in girls. These results further support the need to test the association of modern dietary patterns with allergic symptoms.

Proposition of a New POLA Index to Assess the Immunomodulatory Properties of the Diet and Its Relationship with the Gut Microbiota, Using the Example of the Incidence of COVID-19 in a Group of People without Comorbidities

A rise in the incidence of infections with severe acute respiratory syndrome coronavirus 2 has sparked the search for protective strategies against the new pathogen. It is known that individual food components can interact with different immune cells, modulating the immune response of the body. The aim of this study was to develop an index assessing the immunomodulatory potential of diet (POLA index) and to test its utility for the prediction of coronavirus disease 2019 (COVID-19) in a group of healthy young people following a traditional or vegetarian diet. Data on body composition, anthropometric measurements, physical activity, dietary intake, and gut microbiota were obtained from 95 adults (mean age, 34.66 ± 5.76 years). There was a strong correlation between the dietary inflammatory index and the POLA index (r = 0.90; p < 0.0001). Based on Cohen’s kappa statistic, there was a good agreement in qualitative interpretation between the two indices (kappa = 0.61; p < 0.0001). People on a diet with beneficial immunomodulatory effects had a lower risk of COVID-19 of approximately 80%, as compared with those on a diet with highly unbeneficial immunomodulatory effects. In daily practice, the POLA index might serve as a useful tool for dietitians to identify individuals whose diet is deficient in ingredients for optimal immune system function and change their dietary behavior to ensure optimal immune function that reduces the risk of infection.

Allergic Inflammation: Effect of Propolis and Its Flavonoids

The incidence of allergic diseases and their complications are increasing worldwide. Today, people increasingly use natural products, which has been termed a "return to nature". Natural products with healing properties, especially those obtained from plants and bees, have been used in the prevention and treatment of numerous chronic diseases, including allergy and/or inflammation. Propolis is a multi-component resin rich in flavonoids, collected and transformed by honeybees from buds and plant wounds for the construction and adaptation of their nests. This article describes the current views regarding the possible mechanisms and multiple benefits of flavonoids in combating allergy and allergy-related complications. These benefits arise from flavonoid anti-allergic, anti-inflammatory, antioxidative, and wound healing activities and their effects on microbe-immune system interactions in developing host responses to different allergens. Finally, this article presents various aspects of allergy pathobiology and possible molecular approaches in their treatment. Possible mechanisms regarding the antiallergic action of propolis on the microbiota of the digestive and respiratory tracts and skin diseases as a method to selectively remove allergenic molecules by the process of bacterial biotransformation are also reported.

Deciphering the immunoboosting potential of macro and micronutrients in COVID support therapy

The immune system protects human health from the effects of pathogenic organisms; however, its activity is affected when individuals become infected. These activities require a series of molecules, substrates, and energy sources that are derived from diets. The consumed nutrients from diets help to enhance the immunity of infected individuals as it relates to COVID-19 patients. This study aims to review and highlight requirement and role of macro- and micronutrients of COVID-19 patients in enhancing their immune systems. Series of studies were found to have demonstrated the enhancing potentials of macronutrients (carbohydrates, proteins, and fats) and micronutrients (vitamins, copper, zinc, iron, calcium, magnesium, and selenium) in supporting the immune system's fight against respiratory infections. Each of these nutrients performs a vital role as an antiviral defense in COVID-19 patients. Appropriate consumption or intake of dietary sources that yield these nutrients will help provide the daily requirement to support the immune system in its fight against pathogenic viruses such as COVID-19.

Immunoregulatory Intestinal Microbiota and COVID-19 in Patients with Type Two Diabetes: A Double-Edged Sword

Coronavirus disease 2019, or COVID-19, is a major challenge facing scientists worldwide. Alongside the lungs, the system of organs comprising the GI tract is commonly targeted by COVID-19. The dysbiotic modulations in the intestine influence the disease severity, potentially due to the ability of the intestinal microbiota to modulate T lymphocyte functions, i.e., to suppress or activate T cell subpopulations. The interplay between the lungs and intestinal microbiota is named the gut-lung axis. One of the most usual comorbidities in COVID-19 patients is type 2 diabetes, which induces changes in intestinal microbiota, resulting in a pro-inflammatory immune response, and consequently, a more severe course of COVID-19. However, changes in the microbiota in this comorbid pathology remain unclear. Metformin is used as a medication to treat type 2 diabetes. The use of the type 2 diabetes drug metformin is a promising treatment for this comorbidity because, in addition to its hypoglycemic action, it can increase amount of intestinal bacteria that induce regulatory T cell response. This dual activity of metformin can reduce lung damage and improve the course of the COVID-19 disease.

Altered Differentiation and Inflammation Profiles Contribute to Enhanced Innate Responses in Severe COPD Epithelium to Rhinovirus Infection

Background

Respiratory viral infections are closely associated with COPD exacerbations, hospitalisations, and significant morbidity and mortality. The consequences of the persisting inflammation and differentiation status in virus associated severe disease is not fully understood. The aim of this study was to evaluate barrier function, cellular architecture, the inflammatory response in severe COPD bronchial epithelium to human rhinovirus (HRV) induced pathological changes and innate immune responses.

Methods

Well-differentiated primary bronchial epithelial cells (WD-PBECs) derived from severe COPD patients and age-matched healthy controls were cultured in the air-liquid interface (ALI) model. The differentiation phenotype, epithelial barrier integrity, pathological response and cytokine secreting profile of these cultures before and after HRV infection were investigated.

Results

WD-PBECs derived from severe COPD patients showed aberrant epithelium differentiation with a decreased proportion of ciliated cells but increased numbers of club cells and goblet cells compared with healthy controls. Tight junction integrity was compromised in both cultures following HRV infection, with heightened disruptions in COPD cultures. HRV induced increased epithelial cell sloughing, apoptosis and mucus hypersecretion in COPD cultures compared with healthy controls. A Th1/Th2 imbalance and a strong interferon and pro-inflammatory cytokine response was also observed in COPD cultures, characterized by increased levels of IFNγ, IFNβ, IP-10, IL-10 and decreased TSLP and IL-13 cytokine levels prior to HRV infection. Significantly enhanced basolateral secretion of eotaxin 3, IL-6, IL-8, GM-CSF were also observed in both mock and HRV infected COPD cultures compared with corresponding healthy controls. In response to HRV infection, all cultures displayed elevated levels of IFNλ1 (IL-29), IP-10 and TNFα compared with mock infected cultures. Interestingly, HRV infection dramatically reduced IFNλ levels in COPD cultures compared with healthy subjects.

Conclusion

An altered differentiation phenotype and cytokine response as seen in severe COPD WD-PBECs may contribute to increased disease susceptibility and an enhanced inflammatory response to HRV infection.