The correlation between serum selenium, zinc, and COVID-19 severity: an observational study

Association of Serum Zinc and Selenium Levels with Infection in Patients With Stroke

Background and aims: Patients with acute stroke are vulnerable to infectious diseases due to low consciousness, aspiration, dysphagia, and underlying conditions. Zinc and selenium play critical roles in boosting the immune system. This study aimed to compare serum zinc and selenium levels in patients with stroke before and after infection. Methods: The present prospective study was conducted on patients with stroke in Hamadan, west of Iran, from 2019 to 2020. Serum levels of zinc and selenium were measured before and after infection in patients with stroke. The calculated sample size for this study was 78 patients. A paired t-test was used to compare the mean zinc and selenium levels. The linear regression model was used to assess the association of clinical and para-clinical factors with the change in the serum level of selenium after infection. The level of statistical significance was 0.05. Results: The mean (±SD) age of participants was 71.33±14.27 years, and 55.1% of the participants were female. The mean (±SD) serum zinc levels before and after infection were 80.4±7.6 µg/dL and 74.3±7.9 µg/dL, respectively, indicating a significant difference (P<0.001). These values for selenium were 118.1±42.8 µg/dL and 78.4±29.4 µg/dL, respectively (P<0.001). There was a significant association between sepsis and decreases in the levels of selenium (-28.86 µg/dL, 95% CI: -56.13, -1.59) and zinc (-9.84 µg/dL, 95% CI: -16.12, -3.56). Conclusion: Based on our results, the levels of zinc and selenium in patients with stroke significantly decrease after infection compared to before infection.

Role of Metals on SARS-CoV-2 Infection: a Review of Recent Epidemiological Studies

PURPOSE OF REVIEW

Metals and metalloids are known for their nutritional as well as toxic effects in humans. In the context of the SARS-CoV-2 pandemic, understanding the role of metals on COVID-19 infection is becoming important due to their role in infectious diseases. During the past 2 years, a significant number of studies have examined the impact of metals and metalloids on COVID-19 morbidity and mortality. We conducted a systematic review of peer-reviewed manuscripts on the association of metals and metalloids with SARS-CoV-2 infection and COVID-19 severity published since the onset of the pandemic.

RECENT FINDINGS

We searched for epidemiological studies available through the PubMed database published from January 2020 to December 2022. Of 92 studies identified, 20 met our inclusion criteria. These articles investigated the association of zinc (Zn), iron (Fe), selenium (Se), manganese (Mn), cadmium (Cd), arsenic (As), copper (Cu), magnesium (Mg), chromium (Cr), and/or lead (Pb) levels on SARS-CoV-2 infection and/or COVID-19 severity. Of the ten metals and metalloids of interest that reported either positive, negative, or no associations, Zn yielded the highest number of articles (n = 13), followed by epidemiological studies on Se (n = 7) and Fe (n = 5). Elevated serum Zn and Se were associated with reduced COVID-19 severity and mortality. Similarly, higher levels of serum Fe were associated with lower levels of cellular damage and symptoms of SARS-CoV-2 infection and with faster recovery from COVID-19. On the other hand, higher serum and urinary Cu and serum Mg levels were associated with higher COVID-19 severity and mortality. Along with the positive or negative effects, some studies reported no impact of metals on SARS-CoV-2 infection. This systematic review suggests that metals, particularly Zn, Fe, and Se, may help reduce the severity of COVID-19, while Cu and Mg may aggravate it. Our review suggests that future pandemic mitigation strategies may evaluate the role of Zn, Se, and Fe as potential therapeutic interventions.

The Association Between Antioxidants and COVID-19 Outcomes: a Systematic Review on Observational Studies

It is proven that the blood concentration of antioxidants can impress the severity of viral infections, including COVID-19. However, the lack of a comprehensive study accumulating existing data regarding COVID-19 can be perceived. Therefore, this systematic review is aimed to report the association between the blood concentration of several antioxidants and the overall health condition of COVID-19 patients. We summarized the available data surrounding the serum antioxidant level in COVID-19 patients and COVID-19 outcomes. A systematic search was performed in PubMed, Scopus, Web of Science, and Cochrane, and studies that evaluated the association between antioxidants and COVID-19 outcomes were included. Of 4101 articles that were viewed in the database search, 38 articles were included after the title, abstract, and full-text review. Twenty-nine studies indicated that lower serum antioxidants are associated with worse outcomes, and one study reported no association between serum zinc (Zn) level and COVID-19 outcomes. In most cases, antioxidant deficiency was associated with high inflammatory factors, high mortality, acute kidney injury, thrombosis, intensive care unit (ICU) admission, acute respiratory distress syndrome, cardiac injury, and the need for mechanical ventilation (MV), and there was no significant association between serum antioxidants level and ICU or hospital length of stay (LOS). It seems that higher levels of antioxidants in COVID-19 patients may be beneficial to prevent disease progression. However, clinical trials are needed to confirm this conclusion.

Plant-based diet and COVID-19 severity: results from a cross-sectional study

Although previous findings have shown the beneficial role of healthy eating pattern on the human immune system, the association between plant-based diet and COVID-19 severity has not yet been elucidated. This study aimed to determine the possible role of plant-based diet index (PDI) in COVID-19 severity. This cross-sectional, multicentral study was conducted on 141 patients with confirmed COVID-19. Dietary intakes of the patients were evaluated using a validated food frequency questionnaire. Then, PDI was compared between patients who needed to be hospitalised (considered severe cases), and those who got treatment at home (considered non-severe cases). After adjustment for confounders including age, sex, energy intake and body mass index, lower odds of hospitalisation were found for participants having a greater score of overall PDI (OR per 10 units increase: 0.42; 95% CI 0.22 to 0.80) and healthy PDI (OR per 10 unit increase: 0.45; 95% CI 0.26 to 0.78). In conclusion, our data presented that there is a relation between PDI and lower risk of hospitalisation in COVID-19 patients, possibly through boosting the immune function.

Zinc and selenium status in coronavirus disease 2019

We systematically analyzed and attempted to discuss the possibility that deficiencies of zinc or selenium were associated with the incidence and severity of COVID-19. We searched for published and unpublished articles in PubMed, Embase, Web of Science and Cochrane up to 9 February 2023. And we selected healthy individuals, mild/severe, and even deceased COVID-19 patients to analyze their serum data. Data related to 2319 patients from 20 studies were analyzed. In the mild/severe group, zinc deficiency was associated with the degree of severe disease (SMD = 0.50, 95% CI 0.32-0.68, I2 = 50.5%) and we got an Egger's test of p = 0.784; but selenium deficiency was not associated with the degree of severe disease (SMD = - 0.03, 95% CI - 0.98-0.93, I2 = 96.7%). In the surviving/death group, zinc deficiency was not associated with mortality of COVID-19 (SMD = 1.66, 95%CI - 1.42-4.47), nor was selenium (SMD = - 0.16, 95%CI - 1.33-1.01). In the risk group, zinc deficiency was positively associated with the prevalence of COVID-19 (SMD = 1.21, 95% CI 0.96-1.46, I2 = 54.3%) and selenium deficiency was also positively associated with the prevalence of it (SMD = 1.16, 95% CI 0.71-1.61, I2 = 58.3%). Currently, serum zinc and selenium deficiencies increase the incidence of COVID-19 and zinc deficiency exacerbates the disease; however, neither zinc nor selenium was associated with mortality in patients with COVID-19. Nevertheless, our conclusions may change when new clinical studies are published.

Selenium serum levels in patients with SARS-CoV-2 infection: a systematic review and meta-analysis

The nutritional status is a determinant of the immune response that promotes a cellular homeostasis. In particular, adequate selenium levels lead to a better antioxidant and immune response. The aim of this work is to assess whether blood selenium levels, at time of SARS-CoV-2 infection, have an impact on the development and severity of COVID-19. A systematic review and meta-analysis of comparative and descriptive studies using MeSH terms, selenium and COVID-19 was performed. We searched bibliographic databases up to 17 July 2022 in PubMed and ScienceDirect. Studies that reported data on blood selenium levels were considered. A total of 629 articles were examined by abstract and title, of which 595 abstracts were read, of which 38 were included in the systematic review and 11 in the meta-analysis. Meta-analysis was conducted to mean difference (MD) with a 95 % confidence interval (CI), and heterogeneity was tested by I2 with random factors with a MD between selenium levels, mortality, morbidity and healthy subjects with a P-value of 0⋅05. Selenium levels were higher in healthy people compared to those in patients with COVID-19 disease (six studies, random effects MD: test for overall effect Z = 3⋅28 (P = 0⋅001), 97 % CI 28⋅36 (11⋅41-45⋅31), P < 0⋅00001), but without difference when compared with the degree of severity in mild, moderate or severe cases. In conclusion, the patients with active SARS-CoV-2 infection had lower selenium levels than the healthy population. More studies are needed to evaluate its impact on clinical severity through randomised clinical trials.

Utilization of Marine Seaweeds as a Promising Defense Against COVID-19: a Mini-review

COVID-19 is an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) which mainly affects the respiratory system. It has been declared as a "pandemic" in March 2020 by the World Health Organization due to the high spreading rate. SARS-CoV-2 binds with the angiotensin-converting enzyme 2 (ACE2) receptors on the cell surface which leads to the downregulation of ACE2 and upregulation of angiotensin-converting enzyme (ACE) receptors. The elevated level of cytokines and ACE receptors leads to the severity of SARS-CoV-2 infection. Due to the limited availability of vaccines and recurrent attacks of COVID-19 mainly in low-income countries, it is important to search for natural remedies to prevent or treat COVID-19 infection. Marine seaweeds are a rich source of bioactive compounds such as phlorotannins; fucoidan; carotenoids; omega-3 and omega-6 fatty acids; vitamins B₁₂, D, and C; and minerals including zinc and selenium that exhibit antioxidant, antiviral, and anti-inflammatory activities. Furthermore, bioactive compounds present in marine seaweeds have the ability to inhibit ACEs by inducing ACE2 which exhibits anti-inflammatory effects in COVID-19. Correspondingly, soluble dietary fibers present in seaweeds are served as prebiotics by generating short-chain fatty acids through fermentation. Hence, seaweeds can be utilized to reduce the gastrointestinal infections associated with SARS-CoV-2 infection.

Could Selenium Supplementation Prevent COVID-19? A Comprehensive Review of Available Studies

The purpose of this review is to systematically examine the scientific evidence investigating selenium's relationship with COVID-19, aiming to support, or refute, the growing hypothesis that supplementation could prevent COVID-19 etiopathogenesis. In fact, immediately after the beginning of the COVID-19 pandemic, several speculative reviews suggested that selenium supplementation in the general population could act as a silver bullet to limit or even prevent the disease. Instead, a deep reading of the scientific reports on selenium and COVID-19 that are available to date supports neither the specific role of selenium in COVID-19 severity, nor the role of its supplementation in the prevention disease onset, nor its etiology.

Zinc levels of patients with a moderate to severe COVID-19 infection at hospital admission and after 4th days of ward hospitalization and their clinical outcome

BACKGROUND

Previous studies associate the disturbance of the Zinc (Zn) status with the severity of the disease and the inflammatory process in the critically ill patient. This decrease in Zn concentrations is an indicator of poor prognosis. Our aim was to evaluate Zn levels at admission and after four days, and to study if lower Zn levels at those days were related to a worse clinical outcome.

MATERIAL AND METHODS

Observational cohort study at a tertiary Hospital. Recruitment period: 09/04/2020-04/24/2021. Clinical information on hypertension, diabetes mellitus (DM), chronic obstructive pulmonary disease (COPD), or bronchial asthma was collected. Obesity was defined as BMI ≥ 30 Kg/m2. Blood extraction was performed at admission and after 4 days. Zn was measured by atomic absorption using a flame method. Worse clinical outcome was defined as death during admission, intensive critical care unit admission or receiving supplemental oxygen through noninvasive or invasive ventilator care.

RESULTS

129 subjects were invited to participate but only 100 subjects completed the survey. According to ROC curve [AUC= 0.63 (95% CI 0.60-0.66)], Zn < 79 μg/dL showed the best performance to detect a worse outcome (Sn=0.85; Sp=0.36). Patients with Zn < 79 μg/dL were older (70 vs 61 y; p = 0.002) with no differences by sex. Most patients presented with fever, dysthermic symptoms and cough, without differences between groups. Pre-existing comorbid conditions did not differ significantly between groups. Less obese subjects were found in the Zn < 79 μg/dL group (21.4 vs 43.3%, p = 0.025). In the univariate analysis, Zn < 79 μg/dL at hospital admission was related to a worse outcome (p = 0.044), but after adjusting for age, C-reactive protein, and obesity there was no difference, but a tendency towards a worse prognosis [OR 2.20 (0.63-7.70), p = 0.215]. Zn levels increased in both groups after 4 days (66.6 vs 73.1 μg/dL at admission, and 72.2 vs 80.5 μg/dL at 4th day), with ns. difference (p = 0.214).

CONCLUSION

Zn < 79 μg/dL at admission for a moderate to severe COVID-19 infection could be related to a worse outcome, although after adjustment for age, C-reactive protein levels and obesity, this Zn level threshold did not show statistically significant difference in the composite end point, but a tendency towards a worse prognosis. In addition, patients with the best clinical evolution showed higher serum Zn levels at 4th day after hospital admission than the patients with a worse prognosis.

Immunomodulatory Role of Microelements in COVID-19 Outcome: a Relationship with Nutritional Status

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes coronavirus disease 2019 (COVID-19). SARS-CoV-2 infection can activate innate and adaptive immune responses and result in massive inflammatory responses in the disease. A comprehensive understanding of the participation of micronutrients in the immune response to COVID-19 will allow the creation of prevention and supplementation scenarios in malnutrition states. Microelement deficiency can be decisive in the progression of diseases and their optimal levels can act as protective factors, helping to maintain homeostasis. Vitamin A, B, D, selenium, zinc, and copper, through their complementary and synergistic effects, allow the components of innate and adaptive immunity to counteract infections like those occurring in the respiratory tract.Thus, alterations in nutritional status are related to metabolic diseases, systemic inflammation, and deterioration of the immune system that alter the response against viral infections, such as COVID-19. The aim of this review is to describe the micronutrients that play an important role as immunomodulators and its relationship between malnutrition and the development of respiratory infections with an emphasis on severe and critical COVID-19. We conclude that although an unbalanced diet is not the only risk factor that predisposes to COVID-19, a correct and balanced diet, which provides the optimal amount of micronutrients and favors an adequate nutritional status, could confer beneficial effects for prevention and improvement of clinical results. The potential usefulness of micronutrient supplementation in special cases is highlighted.

COVID-19, the Gut, and Nutritional Implications

PURPOSE OF REVIEW

Our goal is to provide the most recent and accurate scientific evidence available regarding COVID-19's interaction with the human gut and the role of nutrition/nutritional supplementation in the prevention and treatment of the disease.

RECENT FINDINGS

Gastrointestinal symptoms of COVID-19 are common and often persist even after classically defined illness resolution. Nutritional status and content have been shown to impact infection risk and severity. Well-balanced diets are associated with decreased infection risk/severity, and early nutrition is associated with better outcomes in the critically ill. No specific vitamin supplementation regimen has shown consistent benefit for infection treatment or prevention. The impact of COVID-19 extends far past the pulmonary system, and its impact on the gut should not be ignored. For those interested in adopting lifestyle modifications to prevent severe COVID-19 infection/side effects, consideration should be made for adoption of a well-balanced diet (e.g., Mediterranean style), utilization of probiotics, and addressing nutritional/vitamin deficiencies. Future, high-quality research is needed in this arena.

Selenium Status and Oxidative Stress in SARS-CoV-2 Patients

Background and Objectives: Insufficient intake of essential micronutrient selenium (Se) increases the susceptibility to diseases associated with oxidative stress. The study aim was to assess Se status and oxidative stress in COVID-19 patients depending on severity of the disease. Materials and Methods: Blood plasma of 80 post-COVID-19 disease patients and 40 acutely ill patients were investigated. Concentration of Se was detected by a fluorometric method with di-amino-naphthalene using acidic hydrolysis. Selenoprotein P (Sepp1), malondialdehyde (MDA), and 4-hydroxynonenal (4-HNE) and their metabolite adducts were evaluated by spectrophotometric methods using commercial assay kits. Results: Obtained results demonstrated that Se and Sepp1 concentration in acute patients were significantly (p < 0.05 for Se and p < 0.001 for Sepp1) decreased compared with post-COVID-19 disease patients. However, in post-COVID-19 disease patients, Se values were close to the low limit of the norm for the European population. 4-HNE adducts concentration as a marker of lipid peroxidation was significantly increased in the acute patients group compared to the recovery group (p < 0.001). Conclusions: COVID-19 pathology is characterized by the induction of oxidative stress and suppression of antioxidant defenses during the acute phase. Lower levels of Se and Sepp1 and higher levels of reactive oxygen species reflect this imbalance, highlighting the role of oxidative stress in the disease’s pathogenesis.

COVID-19 Severity Is Associated with Selenium Intake among Young Adults with Low Selenium and Zinc Intake in North Carolina

Background

The effects of coronavirus disease 2019 (COVID-19) remain a global public health emergency because of the ensuing economic burden and death. With robust research into vaccines, antibody treatments, and antiviral drugs for COVID-19, there is still a dearth of evidence on the role of an individual's nutritional status on the severity of COVID-19.

Objective

This study aimed to investigate the association between selenium (Se) and zinc (Zn) status and COVID-19 severity among individuals diagnosed with COVID-19 in North Carolina.

Methods

Subjects (n = 106) were recruited remotely as part of the Nutrition and COVID-19 in North Carolina (NC-NC) study and filled out online screening questionnaires and dietary surveys. Toenail samples from 97 participants were analyzed to determine Se and Zn concentrations. To assess the severity of severe acute respiratory coronavirus (SARS-CoV)-2 infection, subjects were asked about the presence and duration of 10 commonly reported symptoms. These responses were used to calculate a COVID-19 severity index (CSI). The relationship between Se and Zn status (intake and toenail concentrations) and CSI was explored using a regression analysis.

Results

Our results showed that the median (25th, 75th percentiles) dietary Se and Zn intake from selected food sources were 65.2 μg (43.2, 112.9) and 4.3 mg (1.8, 8), respectively. Headache, cough, loss of smell or taste, and fever were reported by at least half of the participants. In stepwise regression analysis, among individuals with low Se and Zn intake (below the median), Se intake was inversely associated with increasing CSI (β = -0.66; 95% CI: -1.21, -0.11; P = 0.02).

Conclusions

Findings from this study support a potential benefit of increasing the intake of dietary Se to mitigate the severity of SARS-CoV-2 infection.

Association of Serum Zinc and Inflammatory Markers with the Severity of COVID-19 Infection in Adult Patients

COVID-19 infection can spread in the host body without any adequate immune response. Zinc is an essential trace element with strong immunoregulatory and antiviral properties and its deficiency might lead to inflammation and oxidative stress. The aim of the current study was to determine the association of serum zinc and inflammatory markers with the severity of COVID-19 infection. This was a prospective observational study in which 123 COVID-19-positive adult patients and 48 controls were recruited. The initial comparative analysis was conducted between COVID-19 patients and controls. COVID-19-positive patients were further divided into three different groups (mild, moderate, and severe) based on the severity of COVID-19 infection. COVID-19 patients showed significantly lower serum zinc levels (8.8 ± 2.3 µmol/L) compared to healthy controls (11.9 ± 1.8 µmol/L). There was a negative correlation between serum zinc levels and the severity of COVID-19 infection (r = −0.584, p < 0.0001) and this effect was independent of age (r = −0.361, p < 0.0001). Furthermore, inflammatory markers showed a positive correlation with the severity of COVID-19 infection and a negative correlation with the levels of serum zinc. The study demonstrated an association between COVID-19 infection with low serum zinc levels and elevated inflammatory markers. Further studies to assess the significance of this observation are needed, which may justify zinc supplementation to mitigate the severity of COVID-19 infection.

Relationship between selenium status, selenoproteins and COVID-19 and other inflammatory diseases: A critical review

The antioxidant effects of selenium as a component of selenoproteins has been thought to modulate host immunity and viral pathogenesis. Accordingly, the association of low dietary selenium status with inflammatory and immunodeficiency has been reported in the literature; however, the causal role of selenium deficiency in chronic inflammatory diseases and viral infection is still undefined. The COVID-19, characterized by acute respiratory syndrome and caused by the novel coronavirus 2, SARS-CoV-2, has infected millions of individuals worldwide since late 2019. The severity and mortality from COVID-19 have been associated with several factor, including age, sex and selenium deficiency. However, available data on selenium status and COVID-19 are limited, and a possible causative role for selenium deficiency in COVID-19 severity has yet to be fully addressed. In this context, we review the relationship between selenium, selenoproteins, COVID-19, immune and inflammatory responses, viral infection, and aging. Regardless of the role of selenium in immune and inflammatory responses, we emphasize that selenium supplementation should be indicated after a selenium deficiency be detected, particularly, in view of the critical role played by selenoproteins in human health. In addition, the levels of selenium should be monitored after the start of supplementation and discontinued as soon as normal levels are reached. Periodic assessment of selenium levels after supplementation is a critical issue to avoid over production of toxic metabolites of selenide because under normal conditions, selenoproteins attain saturated expression levels that limits their potential deleterious metabolic effects.

Preliminary In Vivo Evidence of Oral Selenium Supplementation as a Potentiating Agent on a Vector-Based COVID-19 Vaccine in BALB/c Mice

Evidence of efficacy and toxicity of oral selenium supplementation in vaccine administration against severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) in mice models is scarce. In this study, 4 × 109 virus particles (40 µL) dose of Janssen COVID-19 intramuscular injection vaccine was supplemented with a commercial selenium supplement and sodium selenite orally in BALB/c mice (N = 18). Qualitative determination of anti-spike IgG antibody response using indirect Enzyme-Linked Immunosorbent Assay (ELISA) showed significant (p ≤ 0.001) increase in anti-spike IgG antibody response for mice groups immunized with vaccine and supplemented selenium. Furthermore, cytokine profiling using real-time quantitative polymerase chain reaction also showed an increase in IL-6 and IL-10 mRNA levels normalized using hypoxanthine phosphoribosyl transferase 1 (Hprt1) and glyceraldehyde 3-phosphate dehydrogenase (Gadph) housekeeping genes. There was no statistical significance (p < 0.465) among treated and untreated groups for alanine transaminase (ALT), aspartate transaminase (AST), urea, and creatinine parameters. The study presents preliminary findings and suggests that supplementing Janssen COVID-19 vaccines with selenium can generate more robust immune responses.

Association of Serum Vitamin D level and COVID-19 infection: A Case-control Study

BACKGROUND

Vitamin D is considered a potent modulator of the immune system, albeit its role in COVID-19 infection is a matter of debate. The present study aimed to estimate the association between serum vitamin D levels and COVID-19 among people in Qatar.

METHODS

This case-control study, approved by the Institutional Review Board of Primary Health Care Corporation (PHCC) Qatar, retrospectively evaluated the principal public healthcare sector population data repository retrieved from the cloud-based Electronic Health Record (EHR) software-Cerner, during April 2020-2021. The health records of all adult patients aged >18 years who had undergone the reverse transcription-polymerase chain reaction (RT-PCR) test and whose medical records had documented serum 25-hydroxyvitamin D [25 (OH)D] levels were analyzed.

RESULTS

A total of 924,173 EHRs were extracted, of which 62,451 EHR comprised of 16,446 (26.3%) COVID-19 patients and 46,005 (73.7%) negative-control group patients met the inclusion criteria. The odds ratio (OR) among different categories of vitamin D deficiency (VDD) revealed that people with mild/moderate VDD were 1.18 times (95% CI 1.126-1.258) and those with severe VDD were 1.90 times (95% CI 1.116-1.251) more likely to have COVID-19 infection when compared to the people with optimal serum vitamin D level. On applying multiple logistic regression, the odds of having COVID-19 infection were found to be 1.27 times (95% CI 1.184-1.371) higher among those with mild/moderate VDD and 1.32 times (95% CI 1.206-1.405) higher among those with severe VDD when compared to people with optimal vitamin D level (p < 0.001).

CONCLUSION

Our findings demonstrated a significant association between the suboptimal serum vitamin D level and COVID-19 infection. Further studies are required to determine the effects of VDD on the severity and outcomes of COVID-19 infections.

A six-month study of anti-SARS-CoV-2 BNT162b2 mRNA vaccination: A comparative analysis of essential trace elements and anti-RBD IgG sera levels

BACKGROUND

Although essential trace elements (ETEs) play pivotal roles in life-supporting biochemical processes, their function in innate and adaptive immunity has not been fully elucidated, particularly during immunization. Furthermore, the association between anti-SARS-CoV-2 specific IgG antibodies and ETE levels with vaccine responsiveness has not been investigated.

METHODS

The present study explored the status of ETEs (Mn, Cu, Zn, and Se) in sera of healthy women before and after vaccination with the anti-SARS-CoV-2 BNT162b2 mRNA vaccine in a follow-up period of six months. The main aim was to explore links between ETE levels and IgG antibodies produced against Spike glycoprotein's Receptor-Binding Domain (RBD).

RESULTS

A recombinant protein of SARS-CoV-2 comprising the receptor binding domain was successfully expressed in HEK-293 T cells. The purified protein was suitable for producing a sensitive antibody detection assay for human serum and monitored seropositivity, indicating a transient response with peak anti-SARS-CoV-2 IgG levels 2 months after vaccination. In parallel to increasing antibody titers, serum concentrations of Cu, Mn, and Se were not affected by vaccination, and concentrations remained relatively constant at the different sampling times during the 6-month observation period. Total serum Zn concentrations were slightly elevated when compared between the first and last sampling dates. Overall, no consistent effects of vaccination on any of the three trace elements analyzed in our study were observed.

CONCLUSION

Vaccination of adult healthy female volunteers with an mRNA vaccine was not associated with consistent changes in serum trace element concentrations over a six-month observation period.

Association of COVID-19 mortality with serum selenium, zinc and copper: Six observational studies across Europe

Introduction

Certain trace elements are essential for life and affect immune system function, and their intake varies by region and population. Alterations in serum Se, Zn and Cu have been associated with COVID-19 mortality risk. We tested the hypothesis that a disease-specific decline occurs and correlates with mortality risk in different countries in Europe.

Methods

Serum samples from 551 COVID-19 patients (including 87 non-survivors) who had participated in observational studies in Europe (Belgium, France, Germany, Ireland, Italy, and Poland) were analyzed for trace elements by total reflection X-ray fluorescence. A subset (n=2069) of the European EPIC study served as reference. Analyses were performed blinded to clinical data in one analytical laboratory.

Results

Median levels of Se and Zn were lower than in EPIC, except for Zn in Italy. Non-survivors consistently had lower Se and Zn concentrations than survivors and displayed an elevated Cu/Zn ratio. Restricted cubic spline regression models revealed an inverse nonlinear association between Se or Zn and death, and a positive association between Cu/Zn ratio and death. With respect to patient age and sex, Se showed the highest predictive value for death (AUC=0.816), compared with Zn (0.782) or Cu (0.769).

Discussion

The data support the potential relevance of a decrease in serum Se and Zn for survival in COVID-19 across Europe. The observational study design cannot account for residual confounding and reverse causation, but supports the need for intervention trials in COVID-19 patients with severe Se and Zn deficiency to test the potential benefit of correcting their deficits for survival and convalescence.

Role of sarcopenia risk in predicting COVID-19 severity and length of hospital stay in older adults: a prospective cohort study

Sarcopenia is more common in the elderly and causes adverse outcomes with increased morbidity and mortality. This prospective cohort study assessed the association of sarcopenia risk with the severity of COVID-19 at the time of admission and during hospitalisation and the length of hospital stay. Two hundred patients (aged ≥ 60 years) who were hospitalised for COVID-19 were enrolled using consecutive sampling between 29 December 2020 and 20 May 2021. The sarcopenia score of the patients was assessed using the Strength, Assistance in walking, Rising from a chair, Climbing stairs, and Falls questionnaire. The severity of COVID-19 was determined using the modified National Early Warning Score (m-NEWS) system for 2019 n-CoV-infected patients at admission (T1), day three (T2) and at discharge (T3). Data were analysed using SPSS, version 22 and STATA, version 14. Of the 165 patients included, thirty four (20·6 %) were at risk of sarcopenia. The length of hospital stay was slightly longer in patients with sarcopenia risk, but the difference was not significant (P = 0·600). The adjusted OR of respiratory rate (RR) > 20 /min at T1 for the sarcopenia risk group was 6·7-times higher than that for the non-sarcopenic group (P = 0·002). According to generalised estimating equations, after adjusting for confounding factors, the m-NEWS score was 5·6 units higher in patients at risk of sarcopenia (P < 0·001). Sarcopenia risk could exacerbate COVID-19 severity and increase RR at admission, as well as the need for oxygen therapy at discharge.

Assessment of Serum Zinc and Selenium Levels in Children with COVID-19

Objective Zinc and selenium levels are being investigated with increasing frequency in adult patients with coronavirus disease 2019 (COVID-19). However, levels of zinc and selenium in children with COVID-19 have not been adequately studied to date.

Methods This prospective, observational study was conducted on 146 pediatric patients diagnosed with COVID-19 and 49 healthy controls between 2020 and 2021. Normal serum zinc reference values were 0.60 to 1.20 µg/mL for children 0 to 10 years old and 0.66 to 1.10 µg/mL for children ≥11 years old. The normal range for serum selenium concentration was considered between 70 and 150 µg/L. Deficiencies were defined for values below the reference range.

Results Zinc and selenium levels were significantly lower in the COVID-19 (+) group compared with the controls (zinc: 0.7 ± 0.2 vs 0.9 ± 0.2 µg/mL, p < 0.001; selenium: 57.1 ± 9.1 vs 66.5 ± 11.4 µg/L, p < 0.01, respectively). Also, zinc and selenium levels were found to be statistically significantly lower in the hospitalized group compared with the outpatient group (zinc: 0.6 ± 0.2 vs 0.8 ± 0.2 µg/mL, p < 0.001; selenium: 52.1 ± 9.6 vs 58.8 ± 8.3 µg/L, p < 0.001). In the receiver operating characteristic curve analysis, selenium levels with a cutoff value of 55.50 µg/L, with 75% sensitivity and 70% specificity, and zinc levels with a cutoff value of 0.7 µg/mL, with 56% sensitivity and 53% specificity, predicted hospitalization.

Conclusion Our data showed that serum zinc and selenium levels were significantly lower in patients with COVID-19 compared with healthy control group. Also, zinc and selenium levels were found to be lower in the hospitalized group compared with the outpatient COVID-19 group.

The impact of vitamin and mineral supplements usage prior to COVID-19 infection on disease severity and hospitalization

The COVID-19 pandemic has caused a global public health emergency. Nutritional status is suggested to be related to the severity of COVID-19 infection. Herein, we aimed to explore the impact of using vitamin and mineral supplements prior to COVID-19 infection on disease severity and hospitalization. In addition, the prior use of aspirin as an anticoagulant on the disease severity was investigated. A cross-sectional, self-administered survey was conducted between March and July 2021. Recovered COVID-19 individuals (age ≥ 18 years, n = 2148) were recruited in the study. A multivariate logistic regression was used to evaluate the associations of supplements and aspirin use with COVID-19 disease severity and hospitalization status. Among the participants, 12.1% reported symptoms consistent with severe COVID-19, and 10.2% were hospitalized due to COVID-19. After adjustment for confounding variables (age, gender, BMI, cigarette smoking status, and the number of comorbidities), the multivariate logistic regression model showed that the consumption of vitamin D supplements prior to COVID-19 infection was associated with a significant decrease in disease severity (OR = 0.68, 95% CI 0.50 - 0.92; P = 0.01), and a lower risk of hospitalization (OR = 0.64, 95% CI 0.45 - 0.89; P = 0.01). On the other hand, there were no significant differences in the frequencies of severe illness and hospitalizations with the consumption of vitamin A, folic acid, vitamin B12, vitamin B complex, vitamin C, zinc, iron, selenium, calcium, magnesium, omega 3, and aspirin before COVID-19 infection. Among the investigated nutrients, the use of vitamin D prior to COVID-19 infection was associated with reduced disease severity and hospitalization. However, more studies are required to confirm this finding.

Circulating trace elements status in COVID-19 disease: A meta-analysis

Trace elements are a group of essential metals or metalloids, which are necessary for life, and present in minute amounts. Despite substantial researches highlighting the importance of trace elements in Coronavirus disease 2019 (COVID-19) diseases, a thorough evaluation of the levels of circulating trace elements is lacking. Therefore, we conducted a systematic review and meta-analysis to evaluate the trace element status (Zn, Fe, Cu, Mg, and Se) in COVID-19 disease. We also assessed the relationship between circulating trace elements and COVID-19 disease severity and survival status during follow-up. We searched comprehensively MEDLINE, Web of Science, CNKI, and WangFang databases without language restriction, between November 1, 2019 and April 1, 2022. The search identified 1,566 preliminary references. A total of 49 studies met the eligibility criteria and were included in the review, and 42 studies were included in the final meta-analysis. Meta-analysis showed that COVID-19 patients had significantly lower circulating Zn (SMD: -0.83, 95% CI: -1.19 to -0.46, P < 0.001), Fe (SMD: -1.56, 95% CI: -2.90 to -0.21, P = 0.023), and Se (SMD: -0.75, 95% CI: -0.94 to -0.56, P < 0.001) levels than healthy controls, and circulating Zn (SMD: -0.47, 95% CI: -0.75 to -0.18, P = 0.002), Fe (SMD: -0.45, 95% CI: -0.79 to -0.12, P = 0.008), and Se (SMD: -0.27, 95% CI: -0.49 to -0.04, P = 0.020) levels were associated with the presence of severity status in COVID-19 patients. Moreover, circulating Fe levels in non-survivors were significantly lower than survivors in COVID-19 (SMD: -0.28, 95% CI: -0.44 to -0.12, P = 0.001). However, there was no significant difference in Cu and Mg levels between COVID-19 patients and controls, severity and non-severity status, and survivors and non-survivors (all P > 0.05). Taken together, COVID-19 patients displayed lower circulating levels of Zn, Fe, and Se, and their levels were associated with severity status. Moreover, circulating Fe levels may provide part of the explanation for the unfavorable survival status. Therefore, we presumed optimistically that supplements of trace elements might provide an adjutant treatment in the early stages of COVID-19.

Systematic review registration

[https://www.crd.york.ac.uk/prospero], identifier [CRD42022348599].

Nutritional Aspects of People Living with HIV (PLHIV) Amidst COVID-19 Pandemic: an Insight

Purpose of Review

This review elaborates the role of malnutrition in PLHIV (people living with HIV) in the context of COVID-19 and emphasis the need of supplementation, dietary intervention, and nutritional counselling in the post-COVID era. One of the most critical challenges among HIV/AIDS patients is malnutrition since it weakens the immune system and increases risk to opportunistic infections. In HIV (human immunodeficiency virus) infection, weight loss is prevalent due to reduced nutritional consumption, malabsorption, abnormal metabolism, and antiretroviral therapy. Sufficient nutrition is required for optimal immune function, as a result, food therapy is now considered an important adjuvant in the treatment of HIV patients.

Recent Findings

Nutritional intervention, such as the use of dietary supplements, can help to prevent nutrient deficiency, lowering the death risk among malnourished HIV population. Immunocompromised individuals are at very high risk for COVID-19 and malnutrition increases the risk of infection by multiple folds. Interventions, such as nutrition education and counselling are important, to improve the condition of HIV Patients by optimising their nutritional status.

Summary

A balanced diet should be one of the most important priorities in preventing PLHIV against the potentially deadly consequences of COVID-19. It is to be ensured that HIV-positive persons continue to get enough and appropriate assistance, such as nutrition and psychological counselling, in the context of COVID-19 infection. The use of telemedicine to maintain nutritional intervention can be beneficial. To meet their nutritional needs and minimise future difficulties, PLHIV infected with COVID-19 should get specialised nutritional education and counselling.

Graphical abstract

Albumin-corrected Zn and available free Zn-binding capacity as indicators of Zn status - potential for clinical implementation

We have established and describe two measurement procedures to diagnose possible zinc (Zn) deficiency; albumin-corrected Zn concentration and available free Zn-binding capacity. Reference intervals for both biomarkers were established in healthy adults from the Danish population. The clinical usefulness of the measurement procedures was investigated in patients with cirrhosis and in patients given parenteral nutrition due to short bowel syndrome. The results of both methods indicate that there is a risk of overdiagnosing Zn deficiency based on low plasma Zn concentrations. Needless Zn supplementation may thus be avoided by using the albumin-corrected Zn concentration or available free Zn-binding capacity.

Zinc and selenium supplementation in COVID-19 prevention and treatment: a systematic review of the experimental studies

BACKGROUND AND AIM

The COVID-19 pandemic has severely affected the world's population in the last two years. Along with non-pharmacological public health interventions, major efforts have also been made to identify effective drugs or active substances for COVID-19 prevention and treatment. These include, among many others, the trace elements zinc and selenium, based on laboratory studies and some observational human studies. However, both of these study designs are not adequate to identify and approve treatments in human medicine, and experimental studies in the form of randomized controlled trials are needed to demonstrate the effectiveness and the safety of any interventions.

METHODS

We undertook a systematic review in which we searched for published and unpublished clinical trials using zinc or selenium supplementation to treat or prevent COVID-19 in the Pubmed, Scopus and ClinicalTrials databases up to 10 January 2022.

RESULTS

Amongst the published studies, we did not find any trial with selenium, whereas we retrieved four eligible randomized clinical trials using zinc supplementation, only one of which was double-blind. One of these trials looked at the effect of the intervention on the rate of new SARS-CoV-2 infections, and three at the COVID-19 clinical outcome in already infected individuals. The study populations of the four trials were very heterogeneous, ranging from uninfected individuals to those hospitalized for COVID-19. Only two studies investigated zinc alone in the intervention arm with no differences in the endpoints. The other two studies examined zinc in association with one or more drugs and supplements in the intervention arm, therefore making it impossible to disentangle any specific effects of the element. In addition, we identified 22 unpublished ongoing clinical trials, 19 on zinc, one on selenium and two on both elements.

CONCLUSION

No trials investigated the effect of selenium supplementation on COVID-19, while the very few studies on the effects of zinc supplementation did not confirm efficacy. Therefore, preventive or therapeutic interventions against COVID-19 based on zinc or selenium supplementation are currently unjustified, although when the results of the on-going studies are published, this may change our conclusion.

Prevalence of Micronutrient Deficiencies in Patients Hospitalized with COVID-19: An Observational Cohort Study

BACKGROUND

A higher risk for severe clinical courses of coronavirus disease 2019 (COVID-19) has been linked to deficiencies of several micronutrients. We therefore studied the prevalence of deficiencies of eight different micronutrients in a cohort of hospitalized COVID-19-patients.

METHODS

We measured admission serum/plasma levels of vitamins A, B12, D, and E, as well as folic acid, zinc, selenium, and copper in 57 consecutively admitted adult patients with confirmed COVID-19 and analyzed prevalence of micronutrient deficiencies and correlations among micronutrient levels. Further, we studied associations of micronutrient levels with severe disease progression, a composite endpoint consisting of in-hospital mortality and/or need for intensive care unit (ICU) treatment with logistic regression.

RESULTS

Median age was 67.0 years (IQR 60.0, 74.2) and 60% (n = 34) were male. Overall, 79% (n = 45) of patients had at least one deficient micronutrient level and 33% (n = 19) had ≥3 deficiencies. Most prevalent deficiencies were found for selenium, vitamin D, vitamin A, and zinc (51%, 40%, 39%, and 39%, respectively). We found several correlations among micronutrients with correlation coefficients ranging from r = 0.27 to r = 0.42. The strongest associations with lower risk for severe COVID-19 disease progression (adjusted odds ratios) were found for higher levels of vitamin A (0.18, 95% CI 0.05-0.69, p = 0.01), zinc (0.73, 95% CI 0.55-0.98, p = 0.03), and folic acid (0.88, 95% CI 0.78-0.98, p = 0.02).

CONCLUSIONS

We found a high prevalence of micronutrient deficiencies in mostly older patients hospitalized for COVID-19, particularly regarding selenium, vitamin D, vitamin A, and zinc. Several deficiencies were associated with a higher risk for more severe COVID-19 courses. Whether supplementation of micronutrients is useful for prevention of severe clinical courses or treatment of COVID-19 warrants further research.

Can Selenium Reduce the Susceptibility and Severity of SARS-CoV-2?-A Comprehensive Review

The SARS-CoV-2 infection is a highly contagious viral infection, which has claimed millions of lives in the last two years. The infection can cause acute respiratory distress, myocarditis, and systemic inflammatory response in severe cases. The interaction of the viral spike protein with the angiotensin-converting enzyme in various tissues causes damage to vital organs and tissues, leading to complications in the post-infection period. Vaccines and antiviral drugs have improved patient response to the infection, but the long-term effect on vital organs is still unknown. Investigations are now focused on supportive nutrient therapies, which can mitigate the susceptibility as well as the long-term complications of COVID-19. Selenium is one such micronutrient that plays a vital role in preventing oxidative stress induced by the virus. Further, selenium is important for effective immune response, controlling systemic inflammation, and maintain overall health of humans. We examine the role of selenium in various aspects of SARS-CoV-2 infection and address the importance of selenium supplementation in reducing the susceptibility and severity of infection in this review.

Exploring diet associations with Covid-19 and other diseases: a Network Analysis-based approach

The current global pandemic, Covid-19, is a severe threat to human health and existence especially when it is mutating very frequently. Being a novel disease, Covid-19 is impacting the patients with comorbidities and is predicted to have long-term consequences, even for those who have recovered from it. To clearly recognize its impact, it is important to comprehend the complex relationship between Covid-19 and other diseases. It is also being observed that people with good immune system are less susceptible to the disease. It is perceived that if a correlation between Covid-19, other diseases, and diet is realized, then caregivers would be able to enhance their further course of medical action and recommendations. Network Analysis is one such technique that can bring forth such complex interdependencies and associations. In this paper, a Network Analysis-based approach has been proposed for analyzing the interplay of diets/foods along with Covid-19 and other diseases. Relationships between Covid-19, diabetes mellitus type 2 (T2DM), non-alcoholic fatty liver disease (NAFLD), and diets have been curated, visualized, and further analyzed in this study so as to predict unknown associations. Network algorithms including Louvain graph algorithm (LA), K nearest neighbors (KNN), and Page rank algorithms (PR) have been employed for predicting a total of 60 disease-diet associations, out of which 46 have been found to be either significant in disease risk prevention/mitigation or in its progression as validated using PubMed literature. A precision of 76.7% has been achieved which is significant considering the involvement of a novel disease like Covid-19. The generated interdependencies can be further explored by medical professionals and caregivers in order to plan healthy eating patterns for Covid-19 patients. The proposed approach can also be utilized for finding beneficial diets for different combinations of comorbidities with Covid-19 as per the underlying health conditions of a patient. Graphical abstract.

Elements and COVID-19: A Comprehensive Overview of Studies on Their Blood/Urinary Levels and Supplementation with an Update on Clinical Trials

Simple Summary

COVID-19 is a disease caused by the SARS-CoV-2 coronavirus spreading mainly through person-to-person contact. It has caused millions of deaths around the world and lasting health problems in individuals who have survived the disease. This review concisely summarizes certain issues related to COVID-19 with a focus on elements and gives an update on clinical trials where some minerals will be tested/have been tested alone or in combination with drugs, vitamins, or plant extracts/herbal formulations in COVID-19 patients and in those at higher COVID-19 risk.

Abstract

The current report provides a brief overview of the clinical features, hematological/biochemical abnormalities, biomarkers, and AI-related strategies in COVID-19; presents in a nutshell the pharmacological and non-pharmacological therapeutic options; and concisely summarizes the most important aspects related to sociodemographic and behavioral factors as well as comorbidities having an impact on this disease. It also gives a brief outline of the effect of selected elements on immune response and collects data on the levels of micro-/macro-elements and toxic metals in the blood/urine of SARS-CoV-2 infected patients and on supplementation with minerals in COVID-19 subjects. Moreover, this review provides an overview of clinical trials based on the use of minerals alone or in combination with other agents that can provide effective responses toward SARS-CoV-2 infection. The knowledge compiled in this report lays the groundwork for new therapeutic treatments and further research on biomarkers that should be as informative as possible about the patient’s condition and can provide more reliable information on COVID-19 course and prognosis. The collected results point to the need for clarification of the importance of mineral supplementation in COVID-19 and the relationships of the levels of some minerals with clinical improvement.

Selenium: An Element of Life Essential for Thyroid Function

Selenium (Se), a microelement essential for life, is critical for homeostasis of several critical functions, such as those related to immune-endocrine function and signaling transduction pathways. In particular, Se is critical for the function of the thyroid, and it is particularly abundant in this gland. Unfortunately, Se deficiency is a very common condition worldwide. Supplementation is possible, but as Se has a narrow safety level, toxic levels are close to those normally required for a correct need. Thus, whether the obtaining of optimal selenium concentration is desirable, the risk of dangerous concentrations must be equally excluded. This review addressed the contribution by environment and food intake on Se circulating levels (e.g., geographical factors, such as soil concentration and climate, and different quantities in food, such as nuts, cereals, eggs, meat and fish) and effects related to its deficiency or excess, together with the role of selenium and selenoproteins in the thyroid pathophysiology (e.g., Hashimoto's thyroiditis and Graves' disease).

Protective Role of Combined Polyphenols and Micronutrients against Influenza A Virus and SARS-CoV-2 Infection In Vitro

Polyphenols have been widely studied for their antiviral effect against respiratory virus infections. Among these, resveratrol (RV) has been demonstrated to inhibit influenza virus replication and more recently, it has been tested together with pterostilbene against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. In the present work, we evaluated the antiviral activity of polydatin, an RV precursor, and a mixture of polyphenols and other micronutrients, named A5+, against influenza virus and SARS-CoV-2 infections. To this end, we infected Vero E6 cells and analyzed the replication of both respiratory viruses in terms of viral proteins synthesis and viral titration. We demonstrated that A5+ showed a higher efficacy in inhibiting both influenza virus and SARS-CoV-2 infections compared to polydatin treatment alone. Indeed, post infection treatment significantly decreased viral proteins expression and viral release, probably by interfering with any step of virus replicative cycle. Intriguingly, A5+ treatment strongly reduced IL-6 cytokine production in influenza virus-infected cells, suggesting its potential anti-inflammatory properties during the infection. Overall, these results demonstrate the synergic and innovative antiviral efficacy of A5+ mixture, although further studies are needed to clarify the mechanisms underlying its inhibitory effect.