Se Deficiency Research Articles

Selenium Deficiency Caused Fibrosis as an Oxidative Stress-induced Inflammatory Injury in the Lungs of Mice.

Selenium (Se) is a vital trace element in the regulation of inflammation and antioxidant reactions in both animals and humans. Se deficiency is rapidly affecting lung function. The present study investigated the molecular mechanism of Se deficiency aggravates reactive oxygen species (ROS)-induced inflammation, leading to fibrosis in lung. Mice fed with different concentrations of Se to establish the model. In the Se-deficient group, the ROS and malondialdehyde (MDA) was increased, and the activities of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), total antioxidant capacity (T-AOC), and catalase (CAT) reduced. The histopathological observation showed that Se deficiency lead to lung texture damage with varying degrees of degeneration, necrosis, shedding of some alveolar epithelial cells, and inflammatory cell infiltration. Immunohistochemistry showed that the expression of α-smooth muscle actin (α-SMA) increased. The fibrosis index was verified with Sirius red staining. The ELISA and qPCR results showed that the inflammatory cytokines (TNF-α and IL-1β) and ECM (collagen I, collagen IV, fibronectin, and laminin) were increased with ROS increasing, which was induced by Se deficiency. The results displayed that oxidative stress with Se deficiency led to an increase in tissue inhibitors of metalloproteinase (TIMPs), but a decrease in matrix metalloproteinases (MMPs). All the results indicated that Se deficiency induced excessive ROS accumulation to generate inflammation, which disrupted ECM homeostasis and aggravated fibrosis in the lung.

MiR-1656 targets GPX4 to trigger pyroptosis in broilers kidney tissues by activating NLRP3 inflammasome under Se deficiency

Selenium (Se) is a vital minor element for the organism. Se deficiency caused inflammation in kidney tissue and regulate the expression of selenoproteins and microRNAs (miRNAs). Pyroptosis involved in the inflammatory response, however, whether microRNA targets GPX4 to regulate Se-deficient kidney tissue pyroptosis is unclear. In this study, broilers were divided into two groups, Control group with 0.3mg/kg Se diet and Se-deficient group with 0.03mg/kg Se diet. The dual luciferase reporter assay system and quantitative real-time PCR (qRT-PCR) were used to screen the specificity of miR-1656 and its target protein in Se-deficient broilers. We tested the pyroptosis-related genes of Se-deficient broilers kidney and miR-1656-transfected primary broilers kidney by qRT-PCR, Western blot (WB) and immunofluorescence staining. Our research indicated that the GPX4 is one of the target genes of miR-1656, and Se deficiency leaded to the overexpression of miR-1656 and the increased expression of pyroptosis-related genes. The overexpression of miR-1656 can induce increased expression of pyroptosis-related genes including NLRP3, Caspase-1, IL-18, and IL-1β by inhibiting the release of GPX4. This study showed that miR-1656 could increase the release of ROS by targeting GPX4, activated the NLRP3 inflammasome, and release the inflammatory factors IL-1β and IL-18 to trigger pyroptosis in the kidney tissue of Se-deficient broilers. This finding may provide new research ideas for kidney injury and cell death due to Se deficiency.

Selenium Levels and Antioxidant Activity in Critically Ill Patients with Systemic Inflammatory Response Syndrome.

The Selenium (Se) status could be an important modifiable factor in critically ill patient outcomes due to the important role of this mineral in several functions. Although there are many clinical trials with Se interventions in the literature, the evidence is not sufficient to establish a common criterion regarding the Se status. Background and aims: An analysis was made of the evolution of selenium (Se) and antioxidant status in critically ill patients with Systemic Inflammatory Response Syndrome (SIRS) over 7 days of staying in the Intensive Care Unit (ICU). Methods: A prospective analytical study was carried out on 65 critically ill patients aged 31–77 years. A healthy control group of 56 volunteers from the same region was recruited to allow comparisons with reference normal values. The selenium levels in both the plasma and erythrocytes were analyzed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Glutathione Peroxidase (GPx) and Superoxide Dismutase (SOD) activity and the Total Antioxidant Capacity (TAC) were measured using kinetic colorimetric methods. Results: Low erythrocyte and plasma Se levels were found at ICU admission in comparison with the healthy reference group (p < 0.001), and the levels further decreased after one week (p < 0.001). Smaller changes in the plasma Se levels were associated with greater changes in the Sequential Organ Failure Assessment (SOFA) score (p < 0.05). The GPx activity in the critically ill was lower than in the control group (p < 0.05), with an inverse correlation to the severity scores at the baseline (p < 0.05) and reaching normal values after one week (p < 0.05). SOD activity was directly correlated to TAC (p = 0.03), with both parameters exhibiting a direct correlation to albumin (p < 0.05) after 7 days of ICU stay. Conclusions: A deficient Se status was observed at ICU admission and worsened further over follow-up regardless of the evolution of the patient severity and the antioxidant parameters. Adequate Se support from the start of admission could preserve and contribute to improve the Se-related outcomes and critical patient recovery during longer periods in the ICU.

Selenium deficiency is associated with disease severity, disrupted reward processing, and increased suicide risk in patients with Anorexia Nervosa

Background & AimsPatients with Anorexia Nervosa (AN) present many nutritional deficiencies (macro- and often also micro-nutrients), possibly explained by their inadequate food intake. Previous studies reported that selenium (Se) deficiency is common in the general population. As Se can be easily added as a supplement, the goal of this study was to evaluate the clinical impact of Se deficiency in patients with AN. MethodsThis cross-sectional study concerned 153 patients with AN (92.9% women) followed at the Eating Disorder Unit of Lapeyronie Academic Hospital, Montpellier, France. Patients underwent an extensive neuropsychological assessment, and completed validated questionnaires. Blood samples were collected for Se quantification. Results were compared with the t-test, Mann-Whitney U, and Chi square tests, and univariate linear and multivariate logistic regression models. ResultsSe plasma levels were below the cut-off of 80 µg/L in 53.6% (N = 82) of patients. AN onset was earlier in patients with Se deficiency, (p = .005), whereas disease duration was comparable between groups (p = .77). General eating disorder symptomatology in the past 28 days (Eating Disorder Examination Questionnaire) was more severe in patients with Se deficiency (p = .010). The suicide risk (MINI International Neuropsychiatric Evaluation) tended to be higher (p = .037), and suicide attempt history was more frequent (28.39% vs 9.85%, p = .004) in patients with low Se levels. Se plasma concentration was negatively correlated with the performance in the temporal delayed discounting task (p = .006). ConclusionsOur findings suggest that in patients with AN, Se plasma concentration might be implicated in disease severity and suicide risk. The finding that Se deficiency in patients with AN was associated only with reward-related processes, but not with other psychological functions suggests the selective involvement of dopamine-related pathways. Our results suggest that it might be useful to monitor the plasma micronutrient profile in patients with AN. Future studies should determine whether Se supplementation in AN might improve clinical outcomes.

Unusual superconductivity in the topological nodal-line semimetal candidate Sn x NbSe2-δ

We report the superconductivity of the topological nodal-line semimetal candidate Sn x NbSe2-δ with a noncentrosymmetric crystal structure. The superconducting transition temperature T c of Sn x NbSe2-δ drastically varies with the Sn concentration x and the Se deficiency δ, and reaches 12 K, relatively higher than those of known topological superconductors. The upper critical field of this compound shows unusual temperature dependence, inconsistent with the WHH theory for conventional type-II superconductors. In a low-Tc sample, the zero-temperature limit of the upper critical field parallel to the ab plane exceeds the Pauli paramagnetic limit estimated from the simple BCS weak coupling model by a factor of ∼ 2, suggestive of unusual superconductivity stabilized in Sn x NbSe2-δ . Together with the robust superconductivity against disorder, these observations indicate that Sn x NbSe2-δ is a promising candidate to explore topological superconductivity.

Front Cover: Selenium Deficiency Induces Pathological Cardiac Lipid Metabolic Remodeling and Inflammation

Mol. Nutr. Food Res. 2022, 66, 202100644 DOI: 10.1002/mnfr.202100644 A pig model was built to investigate the mechanism of selenium (Se, represented by the moon) deficiency on myocardium pathology in mammal. Multi-omics analysis showed that Se deficiency induced oxidative stress and triggered cardiac energy production disorder, increased lipids peroxidation products and proinflammatory factors. This was reported by Chaohua Tang and co-authors in article number 2100644.

Stakeholder interpretation of probabilistic representations of uncertainty in spatial information: an example on the nutritional quality of staple crops

Spatial information, inferred from samples, is needed for decision-making, but is uncertain. One way to convey uncertain information is with probabilities (e.g. that a value falls below a critical threshold). We examined how different professional groups (agricultural scientists or health and nutrition experts) interpret information, presented this way, when making a decision about interventions to address human selenium (Se) deficiency. The information provided was a map, either of the probability that Se concentration in local staple grain falls below a nutritionally-significant threshold (negative framing) or of the probability that grain Se concentration is above the threshold (positive framing). There was evidence for an effect of professional group and of framing on the decision process. Negative framing led to more conservative decisions; intervention was recommended at a smaller probability that the grain Se is inadequate than if the question were framed positively, and the decisions were more comparable between professional groups under negative framing. Our results show the importance of framing in probabilistic presentations of uncertainty, and of the background of the interpreter. Our experimental approach could be used to elicit threshold probabilities which represent the preferences of stakeholder communities to support them in the interpretation of uncertain information.

Selenium, TGF-Beta and Infectious Endemic Cardiopathy: Lessons from Benchwork to Clinical Application in Chagas Disease.

For over 60 years, selenium (Se) has been known as an essential microelement to many biological functions, including cardiovascular homeostasis. This review presents a compilation of studies conducted in the past 20 years related to chronic Chagas disease cardiomyopathy (CCC), caused by Trypanosoma cruzi infection, a neglected disease that represents a global burden, especially in Latin America. Experimental and clinical data indicate that Se may be used as a complementary therapy to prevent heart failure and improve heart function. Starting from the main questions “Is Se deficiency related to heart inflammation and arrhythmogenesis in CCC?” and “Could Se be recommended as a therapeutic strategy for CCC?”, we show evidence implicating the complex and multidetermined CCC physiopathology, discussing its possible interplays with the multifunctional cytokine TGF-β as regulators of immune response and fibrosis. We present two new proposals to face this global public health challenge in vulnerable populations affected by this parasitic disease: fibrosis modulation mediated by TGF-β pathways and the possible use of selenoproteins as antioxidants regulating the increased reactive oxygen stress present in CCC inflammatory environments. We assess the opportunity to consider the beneficial effects of Se in preventing heart failure as a concept to be applied for CCC patients.

Gastrointestinal nematodes and mineral deficiencies in yearling cattle in Santiago del Estero, northern Argentina.

The aims were to study the epidemiology and the effect of gastrointestinal nematodes (GINs) on yearling cattle in a semiarid region in Argentina and to evaluate the mineral serum levels. Ten- to twelve-month-old calves were monitored between November and April 2019. Animals were divided into three groups: untreated control (CONG; n = 20); group treated with moxidectin (MXD, 200µg/kg) every 30-40days (MXDG; n = 20); group equally MXD treated and mineral supplementation administered in November and January (MMG; n = 20). Individual GIN egg counts (epg) and fecal cultures were made every 30-40days. Animal live weight gain was determined. On 7-11-18, 25-1-19, and 3-4-19, serum levels of Se, Cu, Zn, Mg, and Ca were determined by atom absorption spectrophotometry. At the start of the trial, epg values were low (x̄ = 5.5), which increased only in CONG towards the end of the assay (x̄ = 229). In both GMXD and MMG, epg remained very low (x̄ = 4.1). Cooperia spp. (81%) prevailed over Haemonchus spp. (9%) and Oesophagostomum spp. (9%). Deficiency of Se ranged between marginal and important, except for MMG, although mean values were always below normal. Cu was marginally deficient in CONG and MXDG on the first two sampling dates, whereas MMG had normal values after treatment. Mg had low values in the three groups (x̄ = 1.5mg/dl), whereas Ca and Zn exhibited normal values. Live weight gain (LWG) was higher in MMG than in MXDG, with significant differences (p < 0.05) by mid-January and then, when epg increased, dewormed groups showed higher LWG (p < 0.034) than CONG. A negative effect of GINs on LWG was observed, as well as low to marginal levels of Se, Cu, and Mg.

Distribution and Determinants of Serum Zinc, Copper, and Selenium Levels among Children under Five Years from Popokabaka, Democratic Republic of Congo: A Cross-Sectional Study.

Information about essential trace elements among children in many African countries, including the Democratic Republic of Congo (DRC), is limited. We aimed to measure the distribution and determinants of serum zinc (Zn), copper (Cu), and selenium (Se) concentrations in a representative sample of children under five years old. We conducted a community-based cross-sectional study in Popokabaka, DRC. Blood samples were drawn from 412 children. The serum concentrations of minerals were measured using inductively coupled plasma–mass spectrometry. The median concentrations (P25–P75) of Zn, Cu, and Se were 61.9 µg/dL (52.8–70.2), 145.5 (120.0–167.0) µg/dL and 5.3 (4.3–6.3) µg/dL. The CRP-adjusted prevalence of serum Se deficiency was 84.1% (95% confidence interval [CI] 81.4–87.0) and of Zn deficiency was 64.6% (95% CI 59.8–69.1%). Only a few children were Cu deficient [1.5% (0.6–3.2)]. Evidence of inflammation (C-reactive protein, >5 mg/L) was associated with a lower Se concentration and higher Cu concentration. Furthermore, serum Se concentration was positively associated with linear growth. The average Cu/Zn molar ratio (2:1) was twice that recommended. Children in western Popokabaka had higher Zn and Se levels than their eastern neighbors. Zinc and selenium deficiencies are common among children in Popokabaka and require attention and prioritization.

Selenium Accumulation and Speciation in Chickpea (Cicer arietinum) Impacted by S in Soils: Potential for Biofortification

Dietary selenium (Se) deficiency is a well-known global problem originating from food crops grown in Se-deficient soil. Agronomic Se biofortification is one of the suitable options to minimize Se deficiency. Sulfur (S) is chemically similar to Se, and the role of S on the uptake and transformation of Se in grain has not been resolved. Considering this, our study examines the influence of S on the speciation and accumulation of Se in two chickpea cultivars (Amber and PBA sheamer) grown in Se-deficient soil under glasshouse conditions. Two doses of S (0 and 14 mg kg–1) as sulfate and three doses of Se (0, 1, and 2 mg kg–1) as selenate (SeVI) were used in a randomized factorial design. The addition of SeVI increased the Se content in grain in both cultivars compared to the control treatment. Speciation of Se analysis in grain showed that most (85%) of the Se accumulated in chickpea grain in the organic forms of Se as SeCys and MeSeCys. At 2 mg/kg Se addition, the biomass and grain yield was significantly reduced (P < 0.01), while S addition tended to increase the yield. Inorganic Se was below 15%, primarily as SeVI. PBA Sheamer, a desi type and widely grown chickpea cultivar, showed the most significant proportion of organic Se species, SeCys (57%) and SeMeCys (40%). Application of S contemporarily with Se showed increased SeMeCys production in the grain of PBA Sheamer cultivar. These findings indicated that the accumulation and speciation of Se in chickpea grain was dependent on both Se and S fertilization.

Humoral immune response to COVID-19 mRNA vaccination in relation to selenium status

The essential trace element selenium (Se) is of central importance for human health and particularly for a regular functioning of the immune system. In the context of the current pandemic, Se deficiency in patients with COVID-19 correlated with disease severity and mortality risk. Selenium has been reported to be associated with the immune response following vaccination, but it is unknown whether this also applies to SARS-CoV-2 vaccines. In this observational study, adult health care workers (n = 126) who received two consecutive anti-SARS-CoV-2 vaccinations by BNT162b2 were followed for up to 24 weeks, with blood samples collected at the first and second dose and at three and 21 weeks after the second dose. Serum SARS-CoV-2 IgG titres, neutralising antibody potency, total Se and selenoprotein P concentrations, and glutathione peroxidase 3 activity were quantified. All three biomarkers of Se status were significantly correlated at all the time points, and participants who reported supplemental Se intake displayed higher Se concentrations. SARS-CoV-2 IgG titres and neutralising potency were highest three weeks after the second dose and decreased towards the last sampling point. The humoral immune response was not related to any of the three Se status biomarkers. Supplemental Se intake had no effect at any time point on the vaccination response as measured by serum SARS-CoV-2 IgG levels or neutralising potency. Overall, no association was found between Se status or supplemental Se intake and humoral immune response to COVID-19 mRNA vaccination.

Mineral micronutrient status and spatial distribution among the Ethiopian population.

Multiple micronutrient deficiencies are widespread in Ethiopia. However, the distribution of Se and Zn deficiency risks has previously shown evidence of spatially dependent variability, warranting the need to explore this aspect for wider micronutrients. Here, blood serum concentrations for Ca, Mg, Co, Cu and Mo were measured (n 3102) on samples from the Ethiopian National Micronutrient Survey. Geostatistical modelling was used to test spatial variation of these micronutrients for women of reproductive age, who represent the largest demographic group surveyed (n 1290). Median serum concentrations were 8·6 mg dl-1 for Ca, 1·9 mg dl-1 for Mg, 0·4 µg l-1 for Co, 98·8 µg dl-1 for Cu and 0·2 µg dl-1 for Mo. The prevalence of Ca, Mg and Co deficiency was 41·6 %, 29·2 % and 15·9 %, respectively; Cu and Mo deficiency prevalence was 7·6 % and 0·3 %, respectively. A higher prevalence of Ca, Cu and Mo deficiency was observed in north western, Co deficiency in central and Mg deficiency in north eastern parts of Ethiopia. Serum Ca, Mg and Mo concentrations show spatial dependencies up to 140-500 km; however, there was no evidence of spatial correlations for serum Co and Cu concentrations. These new data indicate the scale of multiple mineral micronutrient deficiency in Ethiopia and the geographical differences in the prevalence of deficiencies suggesting the need to consider targeted responses during the planning of nutrition intervention programmes.

Evaluation of the association between gastric cancer and plasma selenium in Zambian adults: a case-control study.

There is some evidence that Selenium (Se) is protective against gastric carcinogenesis, but these data are inconsistent. With a predicted increase in gastric cancer cases in Africa over the next 20 years, there is an urgent need to identify strategies that could be employed to prevent the surge. The objective of our study was to investigate the association between gastric cancer and plasma Se levels in Zambian adults. Our method used a case–control study with cases having either confirmed gastric cancer or premalignancies and controls having none. In addition, we measured antibodies against Helicobacter pylori and human immunodeficiency virus. Data were analysed with Stata 15 software using standard statistical methods. Using a normal reference range for Se of 0.9–1.9 μmol/L, 140/159 (88%) study participants had Se deficiency. Plasma Se levels were similar in all the three groups; 0.33 (interquartile range (IQR) 0.14–0.64) μmol/L for patients with gastric cancer, 0.38 (IQR 0.21–0.60) μmol/L for premalignant lesions and 0.28 (IQR 0.14–0.64) μmol/L in controls, (p-values = 0.35 and 0.34, respectively). In conclusion, we found no association between plasma Se levels and gastric cancer or premalignant lesions among adult Zambian adults.

Conservation Agriculture Affects Grain and Nutrient Yields of Maize (Zea Mays L.) and Can Impact Food and Nutrition Security in Sub-Saharan Africa.

Maize is a major staple and plays an essential role in food and nutrition security in Sub-Saharan Africa (SSA). Conservation agriculture (CA), a climate-smart agriculture practise based on minimum soil disturbance, crop residue retention, and crop diversification, has been widely advocated but without extensive research on the impact it may have on maize nutrient composition, and food and nutrition security. This study assessed the grain yield, macro- and micronutrient mineral content, and nutrient yield of eight maize varieties grown in Malawi, and how these are affected by CA practises over two seasons. The minerals were analysed by inductively coupled plasma (ICP) coupled to optical emission spectroscopy (OES) and to mass spectroscopy (MS). Grain yield and Se content differed among the varieties, while C, N, Fe, K, Mg, Mn, P, and Zn were similar. The local variety Kanjerenjere showed lowest grain and nutrient yields. The open-pollinated varieties (OPVs) concentrated more minerals than the F1 hybrids, but the latter showed higher yields for both grain and nutrients. Typical consumption of the eight maize varieties could fully meet the protein and Mg dietary reference intake (DRIs) of Malawian children (1–3 years), as well as Mg and Mn needs of adult women (19–50 years), but their contribution to dietary requirements was low for Fe (39–41%) and K (13–21%). The trials showed that CA increased grain yield (1.2- to 1.8-fold) and Se content (1.1- to 1.7-fold), but that it had no effect on C, K, Mg, P, and Zn, and that N (1.1- to 1.2-fold), Mn (1.1- to 1.8-fold), and Fe (1.3- to 3.4-fold) were reduced. The high increase in grain yield under CA treatments resulted in increased yields of protein and Se, no effect on the yields of K, Mg, Mn, P, Zn, and reduced Fe yield. Conservation agriculture could contribute in reducing the risk of Se deficiency in Malawian women and children but exacerbates the risk of Fe deficiency. A combination of strategies will be needed to mitigate some of the foreseen effects of climate change on agriculture, and food and nutrition security, and improve nutrient intake.

P504 Prospective analysis of micronutrient status and disease course in Inflammatory Bowel Disease

Abstract Background Biochemical deficiencies of iron, B12, vitamin D, vitamin K, folic acid, selenium and zinc are common in patients with Inflammatory Bowel Disease (IBD) and some micronutrient deficiencies have been associated with adverse disease outcomes. This study describes the micronutrient status of a cohort of patients on biologic therapy for IBD and explores the relationship with disease activity. Methods Adult patients with IBD on biologic therapy attending the nurse specialist clinic had 16 serum micronutrients measured alongside routine biochemical screening for disease activity. 12 months of follow up data was collected using electronic patient records. Faecal calprotectin (FCP), albumin and CRP were measured at baseline - patients in whom these biomarkers were within normal range (i.e CRP &amp;lt;10mg/L, albumin &amp;gt;35g/L and FCP &amp;lt;250µg/g) were defined as being in biochemical remission. Disease relapse at follow-up was defined as escalation of maintenance therapy, use of corticosteroid, hospital admission or surgery. Relationships between micronutrient status and time to disease relapse were explored. Results 216 patients (42% female, median age 42, IQR: 30–57) were included. 128 patients had Crohn’s disease (CD). 97 patients were in biochemical remission at enrolment. 12.9% of the total cohort were zinc (Zn) deficient and 6.5% were selenium (Se) deficient. Deficiencies of folate, vitamin C, vitamin B12, vitamin B6 and vitamin D were also prevalent within the cohort. Se deficiency was associated with high CRP (p=.001), low albumin (p=.022), and raised FCP (p=.002) at baseline. Zn deficiency was associated with high CRP (p&amp;lt;.001) and low albumin (p&amp;lt;.001). During the 12 month follow up period, 22/216 patients suffered a disease relapse. Patients with low Zn or low Se levels at baseline were significantly more likely to relapse (p=.007 and p=.019 respectively). In subtype analysis, patients with CD and Zn deficiency were significantly more likely to relapse (p=.003) but this was not the case for UC patients. Patients with UC and Se deficiency were significantly more likely to relapse (p=.001) whereas those with CD were not. Conclusion Zn and Se biochemical deficiencies are common in our cohort of IBD patients on biologic therapy and are predictive of subsequent disease relapse. Whether these signals are causal or a secondary effect of disease activity needs to be explored in future intervention studies.

Vitamins, microelements and the immune system: current standpoint in the fight against coronavirus disease 2019.

Coronavirus disease 2019 (COVID-19) is an acute respiratory disease associated with severe systemic inflammation. The optimal status of vitamins and microelements is considered crucial for the proper functioning of the immune system and necessary for successful recovery. Most patients with respiratory distress in COVID-19 are vitamin and microelement deficient, with vitamin D and Se deficiency being the most common. Anyway, various micronutrient supplements are widely and arbitrarily used for prevention or in the treatment of COVID-19. We aimed to summarise current knowledge about molecular and physiological mechanisms of vitamins (D, A, C, B6, B9 and B12) and microelements (Se, Zn, Cu and Fe) involved in the immune system regulation in consideration with COVID-19 pathogenesis, as well as recent findings related to their usage and effects in the prevention and treatment of COVID-19. In the early course of the pandemic, several, mainly observational, studies reported an association of some micronutrients, such as vitamin C, D and Zn, with severity reduction and survival improvement. Still, emerging randomised controlled trials showed no effect of vitamin D on hospitalisation length and no effect of vitamin C and Zn on symptom reduction. Up to date, there is evidence neither for nor against the use of micronutrients in the treatment of COVID-19. The doses that exceed the recommended for the general population and age group should not be used, except in clinical trials. Benefits of supplementation are primarily expected in populations prone to micronutrient deficiencies, who are, as well, at a higher risk of worse outcomes in COVID-19.

Selenium Deficiency Induces Apoptosis, Mitochondrial Dynamic Imbalance, and Inflammatory Responses in Calf Liver.

Selenium (Se) deficiency significantly impacts the cow breeding industry by reducing the milk quality of dairy cows and affecting the health of calves. The molecular mechanism of Se deficiency-induced damage to calves, however, remains unclear. The present study investigated whether Se deficiency induces oxidative stress, apoptosis, and inflammation in calf liver tissues. We collected the liver tissues of calves with Se deficiency. Experimental results showed that Se deficiency weakened the activity of antioxidant enzymes and increased the accumulation of oxidation products in the liver. Se deficiency also led to excessive fission of the mitochondria and downregulated the expression of the Mfn2 and Opa1 genes in the calf liver. Mitochondrial damage-induced apoptosis by increasing the expression of pro-apoptotic genes such as CytC, Cas3, Cas9, fas, and Cas8, leading to a decrease in energy metabolism. Se deficiency also triggered the expression of inflammatory-related factors such as IL-1β, IL-6, TNF-α, and NF-κB. Taken together, the results suggest that Se deficiency causes oxidative stress, triggers an inflammatory response, disrupts mitochondrial dynamic balance, and then induces apoptosis, eventually leading to calf liver damage. These findings might provide valuable clues for elucidating the mechanism of Se deficiency-induced injury in domestic animals.

Selenium Deficiency Induces Pathological Cardiac Lipid Metabolic Remodeling and Inflammation.

Selenium (Se) disequilibrium is closely involved in many cardiac diseases, although its in vivo mechanism remains uncertain. Therefore, a pig model is created in order to generate a comprehensive picture of cardiac response to dietary Se deficiency. A total of 24 pigs are divided into two equal groups, which were fed a diet with either 0.007mg kg-1 Se or 0.3mg kg-1 Se for 16 weeks. Se deficiency causes cardiac oxidative stress by blocking glutathione and thioredoxin systems and increases thioredoxin domain-containing protein S-nitrosylation. Energy production is disordered, as free fatty acids are overloaded, the tricarboxylic acid cycle is strengthened, and three respiratory chain proteins enhance S-nitrosylation. Excess free fatty acids lead to increased synthesis of diacylglycerol, phosphatidylcholine, and phosphatidylethanolamine, where the latter two are vulnerable to oxidation and causes an increase in malondialdehyde. Moreover, increased palmitic acid enhances de novo ceramide synthesis and accumulation. Additionally, Se deficiency initiates inflammation via cytosolic DNA-sensing pathways, which activates downstream interferon regulatory factor 7 and nuclear factor kappaB. The present study identifies a lipid metabolic vulnerability and inflammation initiation pathway via Se deficiency, which may provide targets for human redox imbalance-induced cardiac disease treatment.

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.