Vitamin A Positively Correlates with Secretory Immunoglobulin A: A Cross-Sectional Study in Omicron COVID-19 Outpatients.

Background: Respiratory tract infections remain among the leading causes of mortality worldwide. The COVID-19 pandemic has highlighted the importance of mucosal immunity in defending against infectious agents. Vitamin A is known to influence the production of secretory immunoglobulin A (SIgA) predominantly in the gut, where it is a critical component of the first line of defense on mucosal surfaces. Methods: This cross-sectional study, conducted 14 days post-positive COVID-19 diagnosis, aimed to determine the relationship between the nutritional status of vitamin A and SIgA levels in COVID-19 outpatients. Serum and saliva samples were collected. Vitamin A nutritional status was determined based on the assessment of dietary intake and the analysis of retinol-binding protein 4 (RBP4). SIgA levels were analyzed from salivary samples. In addition, serum antibodies were analyzed. Results: Dietary vitamin A intake and RBP4 levels positively correlated with SIgA. Patients with higher vitamin A intake showed higher SIgA/IgG1 and SIgA/IgG3 ratios, while those with higher RBP4 levels showed higher SIgA/IgM, SIgA/IgG1, and SIgA/IgG2 ratios. Conclusions: These findings underscore a significant correlation between vitamin A nutritional status and SIgA levels in COVID-19 outpatients, which may suggest the potential importance of maintaining optimal vitamin A levels for the prevention of viral infections.

Vitamin D in Depression: A Potential Bioactive Agent to Reduce Suicide and Suicide Attempt Risk.

Suicide is one of the leading causes of death worldwide. According to the World Health Organization (WHO), every year, more than 700 thousand people die from this cause. Therefore, suicide is a public health issue. The complex interaction between different factors causes suicide; however, depression is one of the most frequent factors in people who have attempted suicide. Several studies have reported that vitamin D deficiency may be a relevant risk factor for depression, and vitamin D supplementation has shown promising effects in the adjunctive treatment of this mood disorder. Among the beneficial mechanisms of vitamin D, it has been proposed that it may enhance serotonin synthesis and modulate proinflammatory cytokines since low serotonin levels and systemic inflammation have been associated with depression and suicide. The present narrative review shows the potential pathogenic role of vitamin D deficiency in depression and suicide and the potential benefits of vitamin D supplementation to reduce their risk.

Efficacy and Safety of Heterologous Booster Vaccination after Ad5-nCoV (CanSino Biologics) Vaccine: A Preliminary Descriptive Study.

Several studies have reported the benefits and safety of heterologous vaccination among different approved vaccines; however, there are no specific reports on the effects of vaccination with the Ad5-nCoV and other vaccines of the same or different technologies. In the present study, we evaluated the neutralizing antibodies percentage against SARS-CoV-2 in Mexican patients immunized with the Ad5-nCoV vaccine six months after its application. Moreover, the effect of the heterologous vaccination with the Ad5-nCoV vaccine and a booster dose of ChAdOx1-S-Nov-19, Ad26.COV2.S, BNT162b2, or mRNA-127 were determined. Our results suggest that a heterologous regimen of one dose with Ad5-nCoV vaccine followed by a booster dose of a different vaccine is safe and induces a stronger humoral immune response.

A review: Antibody-dependent enhancement in COVID-19: The not so friendly side of antibodies.

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), represents an unprecedented global public health emergency with economic and social consequences. One of the main concerns in the development of vaccines is the antibody-dependent enhancement phenomenon, better known as ADE. In this review, we provide an overview of SARS-CoV-2 infection as well as the immune response generated by the host. On the bases of this principle, we also describe what is known about the ADE phenomenon in various viral infections and its possible role as a limiting factor in the development of new vaccines and therapeutic strategies.

[The involvement of vitamin A in the production of secretory IgA in the respiratory epithelium for potential protection against SARS-CoV-2 infection]. / Participación de la vitamina A en la producción de IgA secretora en el epitelio del tracto respiratorio para la potencial protección de infección por SARS-CoV-2.

SARS-CoV-2 continues to infect thousands of people around the world. It has been established that the main transmission mechanism of this virus is via airborne route, which is why it initially infects the respiratory tract. Currently, the effectiveness of medications used against COVID-19 is limited, and although immunization programs have been initiated, there is international inequality in the distribution of vaccines. Accordingly, the search for adjuvant therapies continues to be an alternative for research. Supplementation with vitamin A has been associated to the decrease of mortality from infection; this effect could be mediated by retinoic acid (RA), which is the active metabolite of vitamin A that exerts immunomodulatory functions. According to preclinical studies, RA favors the production of secretory immunoglobulin A (IgA) in the respiratory tract. In addition to this, the retinol-binding protein has been correlated with the concentration of IgA and neutralizing antibodies in patients with influenza. Therefore, this review aims to address the involvement of vitamin A in the production of secretory IgA in the respiratory epithelium in order to highlight its potential protection against SARS-CoV-2 infection.

El SARS-CoV-2 continúa infectando a miles de personas a nivel mundial. Se ha establecido que el principal mecanismo de transmisión del SARS-CoV-2 es por vía aérea, por lo que infecta inicialmente el tracto respiratorio. Actualmente, la eficacia de los fármacos utilizados contra COVID-19 es limitada y a pesar de que los programas de inmunización han iniciado, existe una desigualdad internacional en la distribución de vacunas. En este sentido, la búsqueda de terapias coadyuvantes continúa siendo una alternativa para su investigación. La suplementación con vitamina A se ha asociado con la reducción de mortalidad por infecciones; este efecto podría ser mediado por el ácido retinoico (AR), un metabolito activo de esta vitamina, que ejerce funciones inmunomoduladoras. De acuerdo con estudios preclínicos, el AR favorece la producción de inmunoglobulina A (IgA) secretora en el tracto respiratorio. Aunado a esto, la proteína de unión a retinol se ha correlacionado con la concentración de IgA y anticuerpos neutralizantes en pacientes con influenza. Por lo tanto, la presente revisión tiene como objetivo abordar la participación de la vitamina A en la producción de la inmunoglobulina A secretora en el epitelio del tracto respiratorio para resaltar su potencial función protectora contra la infección por SARS-CoV-2.

Association of Food Intake Quality with Vitamin D in SARS-CoV-2 Positive Patients from Mexico: A Cross-Sectional Study.

One of the micronutrients that has attracted the most attention in relation to COVID-19 is vitamin D. Although several factors affect its sufficiency; it has been argued that an optimal diet can ensure the intake of micronutrients with effects on immune response. Therefore, in this work we aimed to evaluate the food intake quality of SARS-CoV-2 positive Mexican patients and some of the common factors related to vitamin D deficiency. We conducted a cross-sectional study in 40 SARS-CoV-2 positive patients. Serum samples and clinical parameters were collected. Micronutrient intake and food intake quality were assessed with a 24-h dietary recall and the Mini-ECCA v.2, respectively. Thirty-eight percent of the sample had a healthy food intake. The median 25(OH)D concentration was 22.7 ng/mL. A considerable insufficient intake of micronutrients with immunomodulatory effects such as vitamin D (p < 0.0001), vitamin E (p < 0.0001), and zinc (p < 0.0001) was shown. Patients with 25(OH)D sufficiency, defined as a concentration >30 ng/mL, had better food intake quality (p = 0.02) and an intense physical activity (p = 0.03). In conclusion, a better level of food intake quality and intense physical activity are associated with 25(OH)D sufficiency in SARS-CoV-2 positive Mexican patients.

Vitamin D Levels in COVID-19 Outpatients from Western Mexico: Clinical Correlation and Effect of Its Supplementation.

BACKGROUND: The immunomodulatory effects of vitamin D are known to be beneficial in viral infections; it is also known that its deficiency is associated with a prognosis more critical of Coronavirus Disease 2019. This study aimed to determine baseline vitamin D serum concentrations and the effects of its supplementation in asymptomatic or mildly symptomatic Coronavirus Disease 2019 outpatients. METHODS: 42 outpatients were included, 22 of which received a supplement of 10,000 IU of vitamin D3 for 14 days; the remaining 20 outpatients were designated as a control group. Serum levels of transferrin, ferritin, vitamin D, and D-dimer were measured at baseline in both groups. After 14 days, serum levels of total vitamin D were determined in the supplemented group. RESULTS: At baseline, only 19% of infected outpatients had vitamin D levels corresponding to sufficiency. All outpatients with vitamin D insufficiency had at least one symptom associated with the disease, while only 75% of patients with symptoms presented sufficiency. On the seventh and fourteenth day of follow-up, the supplemented group presented fewer symptoms with respect to those non-supplemented. A vitamin D3 dose of 10,000 IU/daily for 14 days was sufficient to raise vitamin D serum concentrations. CONCLUSIONS: Immunomodulatory effects of vitamin D appear to be linked to the development of symptoms in positive outpatients. Vitamin D supplementation could have significant benefits in the Western Mexican population.

Potential immunomodulatory effects of vitamin D in the prevention of severe coronavirus disease 2019: An ally for Latin America (Review).

Currently, the world is under a pandemic of severe acute respiratory syndrome coronavirus 2 (SARS­CoV­2), responsible for coronavirus disease 2019 (COVID­19). This disease is characterized by a respiratory syndrome that can progress to an acute respiratory distress syndrome. To date, limited effective therapies are available for the prevention or treatment of COVID­19; therefore, it is necessary to propose novel treatment options with immunomodulatory effects. Vitamin D serves functions in bone health and has been recently reported to exert protective effects against respiratory infections. Observational studies have demonstrated an association between vitamin D deficiency and a poor prognosis of COVID­19; this is alarming as vitamin D deficiency is a global health problem. In Latin America, the prevalence of vitamin D deficiency is unknown, and currently, this region is in the top 10 according to the number of confirmed COVID­19 cases. Supplementation with vitamin D may be a useful adjunctive treatment for the prevention of COVID­19 complications. The present review provides an overview of the current knowledge of the potential immunomodulatory effects of vitamin D in the prevention of COVID­19 and sets out vitamin D recommendations for the Latin American population.

The Relevance of Selenium Status in Rheumatoid Arthritis.

Rheumatoid arthritis (RA) is an autoimmune and inflammatory disease that can cause joint damage. Among the environmental risk factors, diet plays an important role because it can aggravate or attenuate inflammation. Selenium (Se) is considered an essential trace element since it is a structural component of antioxidant enzymes; however, its concentration can be affected by diet, drugs and genetic polymorphisms. Studies have reported that RA patients have a deficient diet in some food groups that is associated with parameters of disease activity. Furthermore, it has been shown that there is an alteration in serum Se levels in this population. Although some clinical trials have been conducted in the past to analyze the effect of Se supplementation in RA, no significant results were obtained. Contrastingly, experimental studies that have evaluated the effect of novel Se nanoparticles in RA-induced models have shown promising results on the restoration of antioxidant enzyme levels. In particular, glutathione peroxidase (GPx) is an important selenoprotein that could have a modulating effect on inflammation in RA. Considering that RA patients present an inflammatory and oxidative state, the aim of this review is to give an overview of the current knowledge about the relevance of Se status in RA.

Survival analysis of adult patients with ALL in Mexico City: first report from the Acute Leukemia Workgroup (ALWG) (GTLA).

Acute lymphoblastic leukemia (ALL) is a hematologic malignancy characterized by the clonal expansion of hematopoietic lymphoid progenitors. With new target therapies, the survival of adults with ALL has improved in the past few decades. Unfortunately, there are no large ALL patient series in many Latin American countries. Data from the Acute Leukemia Workgroup that includes five Mexico City referral centers were used. Survival was estimated for adult patients with ALL during 2009-2015. In total, 559 adults with ALL were included. The median age was 28 years; 67% were classified into the adolescent and young adult group. Cytogenetic information was available in 54.5% of cases. Of the 305 analyzed cases, most had a normal caryotype (70.5%) and Philadelphia-positive was present in 16.7%. The most commonly used treatment regimen was hyper-CVAD. In approximately 20% of cases, there was considerable delay in the administration of chemotherapy. Primarily refractory cases accounted for 13.1% of patients. At the time of analysis, 26.7% of cases had survived. The 3-year overall survival was 22.1%. The main cause of death was disease progression in 228 (55.6%). Clinical and public health strategies are needed to improve diagnosis, treatment and survivorship care for adult with ALL. This multicentric report represents the largest series in Mexico of adult ALL patients in which a survival analysis and risk identification were obtained.