Selenium and asthma

The correlation between selenium intake and lung function in asthmatic people: a cross-sectional study

Objective

This study aimed to examine the correlation between selenium intake and lung function in asthmatic people.

Methods

A total of 4,541 individuals in the US National Health and Nutrition Examination Survey (NHANES) were included in this study. Multivariate linear regression, variance inflation factor, restricted cubic splines and quantile regression were used to analyze the relationship between Se intake and lung function. We divided selenium intake into four levels based on quartiles: Q1: Se ≤ 76.75 mcg/d; Q2: 76.75-105.1 mcg/d; Q3: 105.1-137.65 mcg/d; and Q4: Se ≥137.65 mcg/d.

Results

Asthma was negatively associated with the Ratio of Forced Expiratory Volume 1st Second to Forced Vital Capacity (FEV1/FVC) (β = -0.04, 95% CI: -0.06 to -0.02) and FEV1 (β = -215, 95% CI: -340 to -90). Se intake was positively associated with Forced Expiratory Volume 1st Second (FEV1) (β =3.30 95% CI: 2.60 to 4.00) and Forced Vital Capacity (FVC) (β =4.30, 95% CI: 3.50 to 5.10). In asthmatic individuals, the positive effects of Se intake on FVC were enhanced with increasing Se intake, while the positive effects of Se intake on FEV1 varied less dramatically. High Se intake (Q4 level, above 137.65 mcg/d) improved FVC (β = 353, 95% CI: 80 to 626) and FEV1 (β = 543, 95% CI: 118 to 969) in asthmatic patients compared to low Se intake (Q1 level, below 76.75 mcg/d). At the Q2 level (76.75-105.1 mcg/d) and Q4 level (Se ≥137.65 mcg/d) of Se intake, the correlation between FEV1 and asthma disappeared.

Conclusion

Our research has revealed a positive correlation between selenium intake and lung function in asthma patients and the strength of this positive correlation is related to the amount of selenium intake. We recommend that asthma patients consume 137.65 mcg to 200 mcg of selenium daily to improve pulmonary function while avoiding the adverse effects of selenium on the human body.

Biomarker and transcriptomics profiles of serum selenium concentrations in patients with heart failure are associated with immunoregulatory processes

BACKGROUND

Low selenium concentrations are associated with worse outcomes in heart failure (HF). However, the underlying pathophysiologic mechanisms remain incompletely understood. Therefore, we aimed to contrast serum selenium concentrations to blood biomarker and transcriptomic profiles in patients with HF.

METHODS

Circulating biomarkers, whole blood transcriptomics and serum selenium measurements in a cohort of 2328 patients with HF were utilized. Penalized linear regression and gene expression analysis were used to assess biomarker and transcriptomics profiles, respectively. As a proof-of-principle, potential causal effects of selenium on excreted cytokines concentrations were investigated using human peripheral blood mononuclear cells (PBMCs).

RESULTS

Mean selenium levels were 60.6 μg/L in Q1 and 122.0 μg/L in Q4. From 356 biomarkers and 20 clinical features, the penalized linear regression model yielded 44 variables with <5 % marginal false discovery rate as predictors of serum selenium. Biomarkers associated positively with selenium concentrations included: epidermal growth factor receptor (EGFR), IFN-gamma-R1, CD4, GDF15, and IL10. Biomarkers associated negatively with selenium concentrations included: PCSK9, TNFSF13, FGF21 and PAI. Additionally, 148 RNA transcripts were found differentially expressed between high and low selenium status (Padj.<0.05; log-fold-change<|0.25|). Enrichment analyses of the selected biomarkers and RNA transcripts identified similar enriched processes, including regulation processes of leukocyte differentiation and activation, as well as cytokines production. The mRNA expression of two selenoproteins (MSRB1 and GPX4) were strongly correlated with serum selenium, while GPX4, SELENOK, and SELENOS were associated with prognosis. In the in-vitro setting, PBMCs supplemented with selenium showed significantly lower abundance of several (pro-)inflammatory cytokines.

CONCLUSION

These data suggest that immunoregulation is an important mechanism through which selenium might have beneficial roles in HF. The beneficial effects of higher serum selenium concentrations are likely because of global immunomodulatory effects on the abundance of cytokines. MSRB1 and GPX4 are potential modulators of and should be pursued in future research.

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.

Higher serum selenium concentration is associated with lower risk of all-cause and cardiovascular mortality among individuals with chronic kidney disease: A population-based cohort study of NHANES

Background

Selenium is an essential nutrient and trace element required for human health and plays an important role in antioxidative and anti-inflammatory processes. However, the long-term impact of selenium levels on the health of patients with chronic kidney disease remains unclear.

Method

Participants in this study were 3,063 CKD adults from the Third National Health and Nutrition Examination Survey (NHANES 1999–2000, 2003–2004, and 2011–2018). The mortality status and the cause of death of the study participants were obtained from the National Death Index records. For all-cause and cardiovascular disease (CVD) mortality, the models employed to estimate hazard ratios (HRs) and 95% CI were Cox proportional hazard models and competing risk models, respectively.

Result

During the follow-up period, 884 deaths occurred, including 336 heart-disease-associated deaths. The median (IQR) concentration of serum selenium was 181.7 (156.1, 201.5) μg/L. After full adjustment, serum selenium levels were associated with a decreased risk of mortality in patients with CKD, including all-cause and CVD mortality (P &lt; 0.001). The multivariate-adjusted HRs (95%CI) were 0.684 (0.549–0.852) for all-cause mortality (Ptrend &lt; 0.001) and 0.513 (0.356–0.739) for CVD mortality (Ptrend &lt; 0.001) when selenium concentrations were compared according to the extreme quartiles. Selenium levels are inversely associated with an increased risk of all-cause mortality and CVD mortality. Similar results were observed in subgroup and sensitivity analyses.

Conclusion

Higher serum selenium concentration was independently associated with a decreased risk of all-cause and CVD mortality in patients with CKD.

Selenium Species and Fractions in the Rock-Soil-Plant Interface of Maize (Zea mays L.) Grown in a Natural Ultra-Rich Se Environment

Selenium (Se) enrichments or deficiency in maize (Zea mays L.), one of the world's most important staple foods and livestock feeds, can significantly affect many people's diets, as Se is essential though harmful in excess. In particular, Se-rich maize seems to have been one of the factors that led to an outbreak of selenosis in the 1980s in Naore Valley in Ziyang County, China. Thus, this region's geological and pedological enrichment offers some insight into the behavior of Se in naturally Se-rich crops. This study examined total Se and Se species in the grains, leaves, stalks, and roots of 11 maize plant samples, Se fractions of soils around the rhizosphere, and representative parent rock materials from Naore Valley. The results showed that total Se concentrations in the collected samples were observed in descending order of soil > leaf > root > grain > stalk. The predominant Se species detected in maize plants was SeMet. Inorganic Se forms, mainly Se(VI), decreased from root to grain, and were possibly assimilated into organic forms. Se(IV) was barely present. The natural increases of Se concentration in soils mainly affected leaf and root dry-weight biomasses of maize. In addition, Se distribution in soils markedly correlated with the weathered Se-rich bedrocks. The analyzed soils had lower Se bioavailability than rocks, with Se accumulated predominantly as recalcitrant residual Se. Thus, the maize plants grown in these natural Se-rich soils may uptake Se mainly from the oxidation and leaching of the remaining organic-sulfide-bound Se fractions. A viewpoint shift from natural Se-rich soils as menaces to possibilities for growing Se-rich agricultural products is also discussed in this study.

Correlation of Serum Selenium in Asthma Patients with Severity of the Disorder

Asthma is characterized by reversible airway obstruction, increased bronchial hyper-responsiveness and chronic inflammation, as well as higher levels of oxidative stress mainly due to decreased antioxidant defenses. Our primary aim was to investigate the correlation of serum selenium (Se) levels with the severity of asthma across gender, age, family history, and prevalence from childhood. Selenium levels in blood samples in 103 asthmatic patients and 103 healthy individuals were evaluated. The obtained data indicated that the mean serum Se levels in asthma patients were found to be twofold lower as compared to the controls (p < 0.001). However, there were no significant differences in the asthmatic patients when gender and age were considered. Patients characterized by family history of asthma and inhaler usage had 8% and 7% lower serum Se concentrations, although the difference was only border significant (p = 0.05). Multiple regression analysis demonstrated a significant inverse association of inhaler usage (β =  - 0.226; p < 0.001) with serum Se levels even after adjustment for asthma severity (β =  - 0.644; p < 0.001). While this report clearly necessitates a more detailed study, it is plausible that Se deficiency leads to impaired immune response, and therefore, Se supplementation might modulate oxidative stress in the lung and could potentially alleviate asthma pathophysiology.

Nutraceuticals and mitochondrial oxidative stress: bridging the gap in the management of bronchial asthma

Asthma is a chronic inflammatory disease primarily characterized by inflammation and reversible bronchoconstriction. It is currently one of the leading causes of morbidity and mortality in the world. Oxidative stress further complicates the pathology of the disease. The current treatment strategies for asthma mainly involve the use of anti-inflammatory agents and bronchodilators. However, long-term usage of such medications is associated with severe adverse effects and complications. Hence, there is an urgent need to develop newer, novel, and safe treatment modalities for the management of asthma. This has therefore prompted further investigations and detailed research to identify and develop novel therapeutic interventions from potent untapped resources. This review focuses on the significance of oxidative stressors that are primarily derived from both mitochondrial and non-mitochondrial sources in initiating the clinical features of asthma. The review also discusses the biological scavenging system of the body and factors that may lead to its malfunction which could result in altered states. Furthermore, the review provides a detailed insight into the therapeutic role of nutraceuticals as an effective strategy to attenuate the deleterious effects of oxidative stress and may be used in the mitigation of the cardinal features of bronchial asthma.

Mineral Micronutrients in Asthma

Asthma represents one of the most common medical issues in the modern world. It is a chronic inflammatory disease characterized by persistent inflammation of the airways and disturbances in redox status, leading to hyperresponsiveness of bronchi and airway obstruction. Apart from classical risk factors such as air pollution, family history, allergies, or obesity, disturbances of the levels of micronutrients lead to impairments in the defense mechanisms of the affected organism against oxidative stress and proinflammatory stimuli. In the present review, the impact of micronutrients on the prevalence, severity, and possible risk factors of asthma is discussed. Although the influence of classical micronutrients such as selenium, copper, or zinc are well known, the effects of those such as iodine or manganese are only rarely mentioned. As a consequence, the aim of this paper is to demonstrate how disturbances in the levels of micronutrients and their supplementation might affect the course of asthma.

Serum selenium levels and asthma among seafood processing workers in Greenland

Selenium levels in the Inuit population of Greenland have been declining during the last decades. The association between Selenium and asthma has been investigated previously, but with conflicting results. The objective was to measure human serum Se (s-Se) in Greenlandic seafood processing workers, to compare with levels recorded in previous decades and to establish if s-Se is associated with asthma or lung function. Data, including questionnaire answers, spirometry, skin-prick test and s-Se from 324 seafood processing workers in Greenland were collected during 2016-2017. Mean s-Se values were compared by t-test and one-way ANOVA. Associations between s-Se and asthma, symptoms from the lower airways at work and lung function were assessed using linear regression. The mean s-Se was 96.2 µg/L. S-Se was higher among non-smokers and workers living in settlements. Workers with asthma did not have s-Se levels significantly different from those of non-asthmatics. We found a positive association between s-Se levels and FEV₁ values. Selenium levels appear to continue declining in Greenland, presumably because of a more Westernised lifestyle. The health effects of declining Selenium levels remain unclear. We did not establish an association between s-Se and asthma, but we did record a positive association between s-Se and FEV₁.

A concise review on the role of selenium for bone cancer applications

Cancer is one of the most challenging health problems in the world. Several clinical treatments have been developed, but all presenting several limitations. Among different types of cancer, bone cancer is less common, and limited new clinical treatment strategies have been proposed. Recently, a range of advanced materials has been investigated and applied for bone cancer treatment applications. However, due to the unique physiological properties of the bone tissue (a load-bearing tissue), the selection of the right type of material or the combination of suitable functional materials and base materials are critical. Selenium has been reported to present specific targeting inhibition effects on bone cancer without affecting the surrounding healthy tissue, revealing a huge potential for the development of new bone cancer treatment strategies. This paper presents a concise review on the use of selenium for bone cancer applications, discussing main synthesis methods, biocompatibility, and cytotoxicity aspects and the combination of selenium with a wide range of ceramics, metals, and polymers. Future perspectives and the novel concept of a dual-functional scaffold for both cancer treatment and new bone regeneration are also discussed.

Lipid Nutrition in Asthma

Asthma is a heterogeneous pulmonary disease that has constantly increased in prevalence over the past several decades. Primary symptoms include airway constriction, airway hyperresponsiveness, and airway remodeling with additional symptoms such as shortness of breath, wheezing, and difficulty breathing. Allergic asthma involves chronic inflammation of the lungs, and the rise in its yearly diagnosis is potentially associated with the increased global consumption of foods similar to the western diet. Thus, there is growing interest into the link between diet and asthma symptoms, with mounting evidence for an important modulatory role for dietary lipids. Lipids can act as biological mediators in both a proinflammatory and proresolution capacity. Fatty acids play key roles in signaling and in the production of mediators in the allergic and inflammatory pathways. The western diet leads to a disproportionate ω-6:ω-3 ratio, with drastically increased ω-6 levels. To counteract this, consumption of fish and fish oil and the use of dietary oils with anti-inflammatory properties such as olive and sesame oil can increase ω-3 and decrease ω-6 levels. Increasing vitamin intake, lowering LDL cholesterol levels, and limiting consumption of oxidized lipids can help reduce the risk of asthma and the exacerbation of asthmatic symptoms. These dietary changes can be achieved by increasing intake of fruits, vegetables, nuts, oily fish, seeds, animal-related foods (eggs, liver), cheeses, grains, oats, and seeds, and decreasing consumption of fried foods (especially fried in reused oils), fast foods, and heavily processed foods.

Food Sources of Selenium and Its Relationship with Chronic Diseases

Selenium (Se) is an essential micronutrient for mammals, and its deficiency seriously threatens human health. A series of biofortification strategies have been developed to produce Se-enriched foods for combating Se deficiency. Although there have been some inconsistent results, extensive evidence has suggested that Se supplementation is beneficial for preventing and treating several chronic diseases. Understanding the association between Se and chronic diseases is essential for guiding clinical practice, developing effective public health policies, and ultimately counteracting health issues associated with Se deficiency. The current review will discuss the food sources of Se, biofortification strategies, metabolism and biological activities, clinical disorders and dietary reference intakes, as well as the relationship between Se and health outcomes, especially cardiovascular disease, diabetes, chronic inflammation, cancer, and fertility. Additionally, some concepts were proposed, there is a non-linear U-shaped dose-responsive relationship between Se status and health effects: subjects with a low baseline Se status can benefit from Se supplementation, while Se supplementation in populations with an adequate or high status may potentially increase the risk of some diseases. In addition, at supra-nutritional levels, methylated Se compounds exerted more promising cancer chemo-preventive efficacy in preclinical trials.

Treatment of chronic airway diseases using nutraceuticals: Mechanistic insight

Respiratory diseases, both acute and chronic, are reported to be the leading cause of morbidity and mortality, affecting millions of people globally, leading to high socio-economic burden for the society in the recent decades. Chronic inflammation and decline in lung function are the common symptoms of respiratory diseases. The current treatment strategies revolve around using appropriate anti-inflammatory agents and bronchodilators. A range of anti-inflammatory agents and bronchodilators are currently available in the market; however, the usage of such medications is limited due to the potential for various adverse effects. To cope with this issue, researchers have been exploring various novel, alternative therapeutic strategies that are safe and effective to treat respiratory diseases. Several studies have been reported on the possible links between food and food-derived products in combating various chronic inflammatory diseases. Nutraceuticals are examples of such food-derived products which are gaining much interest in terms of its usage for the well-being and better human health. As a consequence, intensive research is currently aimed at identifying novel nutraceuticals, and there is an emerging notion that nutraceuticals can have a positive impact in various respiratory diseases. In this review, we discuss the efficacy of nutraceuticals in altering the various cellular and molecular mechanisms involved in mitigating the symptoms of respiratory diseases.

Association between toenail zinc concentrations and incidence of asthma among American young adults: The CARDIA study

BACKGROUND

As an essential micronutrient, zinc plays an important role in modulating the immune system. However, data on the association between zinc concentrations and asthma incidence are sparse, especially in adults.

METHODS

We prospectively followed up 3682 individuals aged 20-32 years without history of asthma or current asthma at baseline from 1987-1988 to 2015-2016. Zinc concentrations were measured in toenail clippings collected at Exam Year 2 using inductively-coupled-plasma mass spectroscopy. Asthma was diagnosed by a physician and/or reported medication use for asthma control with verification. Cox regression was used to model the association between toenail zinc concentrations and asthma incidence.

RESULTS

Over an average of 22.5 years of follow-up, 508 incident cases of asthma were identified. After adjustment for potential confounders, no statistically significant association was found between zinc concentration and asthma incidence (HR = 0.81; 95% CI: 0.62, 1.07; Plinear trend = 0.26). The observed association was not materially modified by sex, body mass index, smoking or atopic status. When stratifying data by race, a significant inverse linear association was found among African Americans (per 1 standard deviation increment in toenail zinc concentrations: HR = 0.86; 95% CI: 0.75, 0.99; Plinear trend = 0.03), but not in Caucasians (HR = 1.07; 95% CI: 0.91, 1.25; Plinear trend = 0.42), though the test for interaction was not statistically significant (Pinteraction = 0.099).

CONCLUSIONS

Findings from this prospective cohort study do not support a significant longitudinal association between toenail zinc concentrations and incidence of asthma among American young adults. Future studies are needed to confirm our findings.

Nutraceuticals against Oxidative Stress in Autoimmune Disorders

Antioxidant mechanisms are constituted of enzymes, endogenous, and non-enzymatic, exogenous, which have the role of counterbalancing oxidative stress. Intake of these compounds occurs in the diet. Vegetables, plants, and fruits contain a wide range of alkaloids, polyphenols, and terpenoids which are called “phytochemicals”. Most of these substances are responsible for the positive properties of fruits and vegetables, which are an essential part of a healthy life with roles in ameliorating chronic illnesses and favoring longevity. Nutraceuticals are substances contained in a food or fragment of it influencing health with positive effects on health helping in precenting or treating disorders. We conducted a review illustrating the principal applications of nutraceuticals in autoimmune disorders. Literature reported several studies about exogenous dietary antioxidant supplementation in diverse autoimmune diseases such as rheumatoid arthritis, lupus, diabetes, and multiple sclerosis. In these pathologies, promising results were obtained in some cases. Positive outcomes were generally associated with a reduction of oxidative stress parameters and a boost to antioxidant systems, and sometimes with anti-inflammatory effects. The administration of exogenous substances through food derivates or dietary supplements following scientific standardization was demonstrated to be effective. Further bias-free and extended studies should be conducted that include ever-increasing oxidative stress biomarkers.

Micronutrients, Phytochemicals and Mediterranean Diet: A Potential Protective Role against COVID-19 through Modulation of PAF Actions and Metabolism

The new coronavirus disease 2019 (COVID-19) pandemic is an emerging situation with high rates of morbidity and mortality, in the pathophysiology of which inflammation and thrombosis are implicated. The disease is directly connected to the nutritional status of patients and a well-balanced diet is recommended by official sources. Recently, the role of platelet activating factor (PAF) was suggested in the pathogenesis of COVID-19. In the present review several micronutrients (vitamin A, vitamin C, vitamin E, vitamin D, selenium, omega-3 fatty acids, and minerals), phytochemicals and Mediterranean diet compounds with potential anti-COVID activity are presented. We further underline that the well-known anti-inflammatory and anti-thrombotic actions of the investigated nutrients and/or holistic dietary schemes, such as the Mediterranean diet, are also mediated through PAF. In conclusion, there is no single food to prevent coronavirus Although the relationship between PAF and COVID-19 is not robust, a healthy diet containing PAF inhibitors may target both inflammation and thrombosis and prevent the deleterious effects of COVID-19. The next step is the experimental confirmation or not of the PAF-COVID-19 hypothesis.

Effects of vitamin E and selenium on allergic rhinitis and asthma pathophysiology

Allergic diseases such as asthma and rhinitis are common health problems that affect hundreds of millions of people in the world. T helper 2 cytokines participate in the immune responses in these diseases. Vitamin E and selenium (Se) are supplementary factors which have immunomodulatory and antioxidant effects. The present study investigated the effects of vit E + Se administration on allergic symptoms in mice models of asthma and rhinitis. Mice were treated with vit E and Se, and the levels of IL-4, IL-5, IL-13, IL-25, IL-33, total IgE, and histamine were measured. Lung histopathology was also analyzed. Our results indicated that vit E could attenuate allergic rhinitis and asthma symptoms; nevertheless, treatment with Se alone was not effective in controlling allergic symptoms. We noticed reduced airway inflammation and constriction and mucus secretion in the mice, especially when vit E was used in combination with Se. Our result suggested that vit E, especially in combination with Se, could control allergic mediators and symptoms in rhinitis and asthma and reduce pulmonary inflammation and airway mucus secretion, helping to open obstructed bronchi.

Design and evaluation a kind of functional biomaterial for bone tissue engineering: Selenium/mesoporous bioactive glass nanospheres

Conventional treatments of bone tumor involve removal followed by radiation and chemotherapeutic drugs that may have limitations and cause secondary damage. The development of functional filling biomaterial has led to a new strategy for tumor therapy. In this study, a novel therapeutic ion selenium doped mesoporous bioactive glasses (Se/MBG) nanospheres were successfully synthesized by a facile sol-gel technique using cetyl trimethyl ammonium bromide (CTAB) as the template, which had uniform spherical morphology (≈ 400 nm), high surface area (>400 m²/g) and mesopore volume (≈0.30 cm³/g). Results showed that hydroxyapatite formation ability and controllable doxorubicin (DOX) release and distinct degradation of Se/MBG nanospheres depended on the dose of Se⁴⁺. In vitro cell cultures showed that both Se/MBG and DOX-Se/MBG nanospheres had the culture time and dose dependent cytotoxicity to MG63 osteosarcoma cells. But DOX-Se/MBG nanospheres reduced the acute cytotoxicity to MG63 because of the co-operative effect of Se and DOX. Meanwhile, Se/MBG nanospheres were found to have selective cytotoxicity to cancer cells (MG63) and normal cells (MC3T3-E1), indicating that the prepared Se/MBG nanospheres had cell recognition function. These all note that the synthesized Se/MBG nanospheres can be used as a filling biomaterial for the bone tissue engineering.

Selenium deficiency exacerbates LPS-induced necroptosis by regulating miR-16-5p targeting PI3K in chicken tracheal tissue

Multiple tissue necrosis is one of the morphological features of selenium deficiency-mediated injury. MicroRNA (miRNA) participates in the occurrence and development of necroptosis by regulating target genes. Necroptosis is a programmed form of necrosis, and it is closely related to lipopolysaccharide (LPS)-induced injury. Our aim was to investigate whether Se deficiency can promote tracheal injury caused by LPS through miRNA-induced necroptosis. By establishing models of tracheal injury in Se-deficient chickens, we verified the targeting relationship between chicken-derived miR-16-5p and PI3K through bioinformatics, qRT-PCR and WB analyses, and we measured the changes in the expression of genes related to the PI3K/AKT pathway, RIP3/MLKL pathway and MAPK pathway and of heat shock proteins. Under the condition of Se deficiency, the following results were observed: PI3K/AKT expression decreased with the upregulation of miR-16-5p, the expression of necroptosis-related factors (TNF-α, RIP1, FADD, RIP3 and MLKL) increased, and the expression of Caspase 8 significantly decreased (p < 0.05). Light microscopy observations indicated that cell necrosis was the main pathological change due to Se deficiency injury in the tracheal epithelium. The MAPK pathway was activated, and HSP expression was upregulated, indicating that the MAPK pathway and HSPs are both involved in Se deficiency-mediated necroptosis. In addition, Se deficiency promoted the expression of necroptosis-related genes in LPS-treated chickens (p < 0.05), and the pathological changes of cell necrosis were more obvious. In conclusion, we demonstrated that Se deficiency regulates the miR-16-5p-PI3K/AKT pathway and exacerbates LPS-induced necroptosis in chicken tracheal epithelial cells by activating necroptosis-related genes.

The Impact of Western Diet and Nutrients on the Microbiota and Immune Response at Mucosal Interfaces

Recent findings point toward diet having a major impact on human health. Diets can either affect the gut microbiota resulting in alterations in the host’s physiological responses or by directly targeting the host response. The microbial community in the mammalian gut is a complex and dynamic system crucial for the development and maturation of both systemic and mucosal immune responses. Therefore, the complex interaction between available nutrients, the microbiota, and the immune system are central regulators in maintaining homeostasis and fighting against invading pathogens at mucosal sites. Westernized diet, defined as high dietary intake of saturated fats and sucrose and low intake of fiber, represent a growing health risk contributing to the increased occurrence of metabolic diseases, e.g., diabetes and obesity in countries adapting a westernized lifestyle. Inflammatory bowel diseases (IBD) and asthma are chronic mucosal inflammatory conditions of unknown etiology with increasing prevalence worldwide. These conditions have a multifactorial etiology including genetic factors, environmental factors, and dysregulated immune responses. Their increased prevalence cannot solely be attributed to genetic considerations implying that other factors such as diet can be a major contributor. Recent reports indicate that the gut microbiota and modifications thereof, due to a consumption of a diet high in saturated fats and low in fibers, can trigger factors regulating the development and/or progression of both conditions. While asthma is a disease of the airways, increasing evidence indicates a link between the gut and airways in disease development. Herein, we provide a comprehensive review on the impact of westernized diet and associated nutrients on immune cell responses and the microbiota and how these can influence the pathology of IBD and asthma.

Dietary intake is associated with respiratory health outcomes and DNA methylation in children with asthma

BACKGROUND

Asthma is an increasingly common chronic disease among children, and data point toward a complex mechanism involving genetic, environmental and epigenetic factors. Epigenetic modifications such as DNA hypo- or hyper-methylation have been shown to occur in response to environmental exposures including dietary nutrients.

METHODS

Within the context of the asthma randomized trial of indoor wood smoke (ARTIS) study, we investigated relationships between diet, asthma health measures, and DNA methylation. Asthma health measures included a quality of life instrument, diurnal peak flow variability (dPFV) and forced expiratory volume in the first second (FEV₁). Dietary intake was assessed with a food frequency questionnaire. Methylation levels of LINE-1 repetitive element and two promoter CpG sites for interferon gamma (IFNγ, -186 and -54) from buccal cell DNA were measured using pyrosequencing assays.

RESULTS

Data were collected on 32 children with asthma living in western Montana who were recruited to the ARTIS study. Selenium and several methyl donor dietary nutrients were positively associated with the asthma quality of life measure. Intake of methyl donating nutrients including folate was positively associated LINE-1 methylation and negatively associated with IFNγ CpG-186. Higher levels of LINE-1 methylation were associated with greater dPFV.

CONCLUSION

We identified several nutrients that were associated with improved quality of life measures among children with asthma. The IFNγ promoter CpG site -186 but not -54 was associated with the intake of selected dietary nutrients. However, in this small population of children with asthma, the IFNγ promoter CpG sites were not associated with respiratory health measures so it remains unclear through which epigenetic mechanism these nutrients are impacting the quality of life measure. These findings add to the evidence that dietary nutrients, particularly foods containing methyl donors, may be important for epigenetic regulation as it pertains to the control of asthma. Trial registration ClincialTrials.gov NCT00807183. Registered 10 December 2008.

Trace Elements Status in Sera of Patients with Allergic Asthma

BACKGROUND

Asthma is a multifactorial disease and its severity varies with the inflammatory grade. There are conflicting reports about the roles of trace elements in asthma. This study examined the effects of zinc (Zn), copper (Cu), and selenium (Se) concentrations in sera of patients with allergic asthma attending Ghaem Hospital, Mashhad, Iran.

METHODS

Forty-nine patients, aged 10 to 50 years, with asthma in moderate or severe stages, and 24 healthy controls, were enrolled in this study. After demographic data collection and clinical evaluations, the subjects' serum concentrations of Zn, Cu, and Se were measured via atomic absorbency.

RESULTS

Mean serum levels of Zn and Se in patients with allergic asthma were lower than in the healthy control group, but the Cu concentration in sera of patients with allergic asthma was slightly higher than healthy controls.

CONCLUSION

Low levels of trace elements, specifically Zn, may have a role in the pathogenesis of allergic asthma; replacement of these elements may be an effective treatment.

Dietary Selenium Levels Affect Selenoprotein Expression and Support the Interferon-γ and IL-6 Immune Response Pathways in Mice

Selenium is an essential element that is required to support a number of cellular functions and biochemical pathways. The objective of this study was to examine the effects of reduced dietary selenium levels on gene expression to assess changes in expression of non-selenoprotein genes that may contribute to the physiological consequences of selenium deficiency. Mice were fed diets that were either deficient in selenium or supplemented with selenium in the form of sodium selenite for six weeks. Differences in liver mRNA expression and translation were measured using a combination of ribosome profiling, RNA-Seq, microarrays, and qPCR. Expression levels and translation of mRNAs encoding stress-related selenoproteins were shown to be up-regulated by increased selenium status, as were genes involved in inflammation and response to interferon-γ. Changes in serum cytokine levels were measured which confirmed that interferon-γ, as well as IL-6, were increased in selenium adequate mice. Finally, microarray and qPCR analysis of lung tissue demonstrated that the selenium effects on immune function are not limited to liver. These data are consistent with previous reports indicating that adequate selenium levels can support beneficial immune responses, and further identify the IL-6 and interferon-γ pathways as being responsive to dietary selenium intake.

Effects of selenium-chitosan on blood selenium concentration, antioxidation status, and cellular and humoral immunity in mice

One hundred and eighty Kunming mice were allotted to three groups in a randomized complete block design, including two treatments and one control. Mice in group 1 were fed a basal diet as control, while mice in groups 2 and 3 were fed the basal diet supplemented with 0.2 mg/kg selenium as sodium selenite (SS) or selenium-chitosan (SC), respectively. On day 28 of the experiment, blood selenium concentration, glutathione peroxidase (GPx) activity, plasma superoxide dismutase (SOD) activity, malondialdehyde (MDA) content, and Con A-induced splenocyte proliferation were determined, and plasma interleukin-2 (IL-2) and interferon-γ (IFN-γ) concentrations, splenic plaque-forming cell (PFC) responses, serum hemolysis level (HC50), and delayed-type hypersensitivity (DTH) responses were determined on day 15 of the experiment. The results showed that blood selenium concentration, GPx activity, splenic PFC response, and plasma IL-2 and IFN-γ concentrations in SC group were higher than those in the control and SS groups (P < 0.01 or P < 0.05), respectively. Plasma SOD activity, Serum hemolysis level, DTH responses, and Con A-induced splenocyte proliferation in SC group were higher than those in control (P < 0.01 or P < 0.05). Plasma SOD activity, serum hemolysis level, DTH responses, and Con A-induced splenocyte proliferation in SC group were also higher than those in SS group, while there was no significant difference between SC and SS groups (P > 0.05). Plasma MDA content in SC group was lower than those in the control and SS groups (P < 0.01 or P < 0.05). It is concluded that SC supplement can increase blood selenium concentration, antioxidation status, and cellular and humoral immunity, and SC has better biological activity than SS in mice.

Selenium and exposure to fibrogenic mineral dust: a mini-review

Individuals exposed to fibrogenic mineral dust may exhibit an impaired antioxidant system and produce high levels of reactive oxygen and nitrogen species through immune cells, contributing to the perturbation of immune cell function, inflammation, fibrosis and lung cancer. The lung diseases which are caused by inhalation of fibrogenic mineral dust, known as pneumoconioses, develop progressively and irreversibly over decades. At the moment there is no known cure. The trace element selenium has potent antioxidant and anti-inflammatory properties mediated mainly through selenoproteins. Research has demonstrated that selenium has the ability to protect against cardiovascular diseases; to kill cancer cells in vitro and reduce cancer incidence; and to immunomodulate various cellular signaling pathways. For these reasons, selenium has been proposed as a promising therapeutic agent in oxidative stress associated pathology that in theory would be beneficial for the prevention or treatment of pneumoconioses such as silicosis, asbestosis, and coal worker's pneumoconiosis. However, studies regarding selenium and occupational lung diseases are rare. The purpose of this study is to conduct a mini-review regarding the relationship between selenium and exposure to fibrogenic mineral dust with emphasis on epidemiological studies. We carried out a systematic literature search of English published studies on selenium and exposure to fibrogenic mineral dust. We found four epidemiological studies. Reviewed studies show that selenium is lower in individuals exposed to fibrogenic mineral dust. However, three out of the four reviewed studies could not confirm cause-and-effect relationships between low selenium status and exposure to fibrogenic mineral dust. This mini-review underscores the need for large follow-up and mechanistic studies for selenium to further elucidate its therapeutic effects.

Cohort study for prevention of atopic dermatitis using hair mineral contents

We undertook a cohort study to determine the association between hair mineral content and the onset of atopic dermatitis (AD) in infants. Eight hundred and thirty-four mother-infant pairs, who donated hair samples during one and ten-month health checkups, had their samples analyzed by proton induced X-ray emission (PIXE) for 32 mineral concentrations, and these mineral concentration data together with their AD family history were statistically examined for any relationships between them. Results indicated that of all minerals, only selenium (Se) and strontium (Sr) showed statistically significant associations for infants, while the same two elements were only marginally significant for mothers. Se deficiency in either infant or mother increased the AD risk. A Sr deficiency in infants increased AD risk, while the same deficiency in mothers decreased the risk. To predict the probability of AD development using this data, we performed logistic regression analysis, which provided a sensitivity of 65.9%, a specificity of 70.5%, a positive predictive value (PPV) of 10.3%, a negative predictive value (NPV) of 97.6% and a relative risk (RR) of 4.2, all far better than any corresponding figures explicitly mentioned in previously published papers.

Hair zinc and selenium levels in children with recurrent wheezing

The prevalence of asthma and other allergic diseases has increased markedly in the last few decades. Oxidative stress plays a central role in asthma pathogenesis, and reduced daily consumption of antioxidants is positively correlated with increased risk of asthma. Zinc (Zn) and selenium (Se) are the main antioxidant elements. In our study, we aimed to investigate hair Zn and Se levels in children with recurrent wheezing. The study included 65 patients with recurrent wheezing (RW) and 65 healthy children (HC). The hair Zn and Se levels (µg/g) of the RW group were lower in comparison with the HC group (162.43 ± 91.52 vs. 236.38 ± 126.44, P < 0.001, and 217.37 ± 83.01 vs. 280.53 ± 122.73, P < 0.001, respectively). Total antioxidant capacity (TAC) (mmol/L) of the RW group was found to be significantly lower in comparison with the HC group (1.38 ± 0.14 vs. 1.53 ± 0.20, respectively; P < 0.001). Number of wheezing episodes in the last 6 months were negatively correlated with serum TAC, hair Zn, and Se levels in RW group (r(p)  = -0.291, P = 0.001; r(p)  = -0.209, P = 0.017; r(p)  = -0.206, P = 0.019, respectively). The number of acute respiratory tract infection (ARTI) episodes in the last 6 months was negatively correlated with serum TAC and hair Zn levels (r(p)  = -0.316, P < 0.001, and r(p)  = -0.196, P = 0.025, respectively). In this study, we found that TAC, hair Zn, and hair Se levels were lower in children with RW than HC and negatively correlated with wheezing episodes in the last 6 months. Also body Zn and Se levels can be reliably measured in hair samples.