The role of vitamin B12 in viral infections: a comprehensive review of its relationship with the muscle-gut-brain axis and implications for SARS-CoV-2 infection

Emerging Roles of Vitamin B12 in Aging and Inflammation

Vitamin B12 (cobalamin) is an essential nutrient for humans and animals. Metabolically active forms of B12-methylcobalamin and 5-deoxyadenosylcobalamin are cofactors for the enzymes methionine synthase and mitochondrial methylmalonyl-CoA mutase. Malfunction of these enzymes due to a scarcity of vitamin B12 leads to disturbance of one-carbon metabolism and impaired mitochondrial function. A significant fraction of the population (up to 20%) is deficient in vitamin B12, with a higher rate of deficiency among elderly people. B12 deficiency is associated with numerous hallmarks of aging at the cellular and organismal levels. Cellular senescence is characterized by high levels of DNA damage by metabolic abnormalities, increased mitochondrial dysfunction, and disturbance of epigenetic regulation. B12 deficiency could be responsible for or play a crucial part in these disorders. In this review, we focus on a comprehensive analysis of molecular mechanisms through which vitamin B12 influences aging. We review new data about how deficiency in vitamin B12 may accelerate cellular aging. Despite indications that vitamin B12 has an important role in health and healthy aging, knowledge of the influence of vitamin B12 on aging is still limited and requires further research.

Laboratory parameters related to disease severity and physical performance after reconvalescence of acute COVID-19 infection

Research into the molecular basis of disease trajectory and Long-COVID is important to get insights toward underlying pathophysiological processes. The objective of this study was to investigate inflammation-mediated changes of metabolism in patients with acute COVID-19 infection and throughout a one-year follow up period. The study enrolled 34 patients with moderate to severe COVID-19 infection admitted to the University Clinic of Innsbruck in early 2020. The dynamics of multiple laboratory parameters (including inflammatory markers [C-reactive protein (CRP), interleukin-6 (IL-6), neopterin] as well as amino acids [tryptophan (Trp), phenylalanine (Phe) and tyrosine (Tyr)], and parameters of iron and vitamin B metabolism) was related to disease severity and patients' physical performance. Also, symptom load during acute illness and at approximately 60 days (FU1), and one year after symptom onset (FU2) were monitored and related with changes of the investigated laboratory parameters: During acute infection many investigated laboratory parameters were elevated (e.g., inflammatory markers, ferritin, kynurenine, phenylalanine) and enhanced tryptophan catabolism and phenylalanine accumulation were found. At FU2 nearly all laboratory markers had declined back to reference ranges. However, kynurenine/tryptophan ratio (Kyn/Trp) and the phenylalanine/tyrosine ratio (Phe/Tyr) were still exceeding the 95th percentile of healthy controls in about two thirds of our cohort at FU2. Lower tryptophan concentrations were associated with B vitamin availability (during acute infection and at FU1), patients with lower vitamin B12 levels at FU1 had a prolonged and more severe impairment of their physical functioning ability. Patients who had fully recovered (ECOG 0) presented with higher concentrations of iron parameters (ferritin, hepcidin, transferrin) and amino acids (phenylalanine, tyrosine) at FU2 compared to patients with restricted ability to work. Persistent symptoms at FU2 were tendentially associated with IFN-γ related parameters. Women were affected by long-term symptoms more frequently. Conclusively, inflammation-mediated biochemical changes appear to be related to symptoms of patients with acute and Long Covid.

Proton pump inhibitors and risk of severe COVID-19 in older people

INTRODUCTION

Severe acute respiratory syndrome coronavirus 2 is a viral respiratory infection that can cause systemic disorders and lead to death, particularly in older people. Proton pump inhibitors (PPIs) increase the risk of enteric and lung infections. Considering the broad use of PPIs in older people, the potential role of PPIs in COVID-19 could be of dramatic significance. The objective of our study was to evaluate the link between PPIs and severe COVID-19 in older people.

METHOD

We performed a retrospective cohort study, including all patients aged ≥65, hospitalised for a diagnosis of COVID-19. Epidemiological, clinical and biological data were extracted and we performed an Inverse Probability of Treatment Weighing method based on a propensity score.

RESULTS

From March 2020 to February 2021, a total of 834 patients were included, with a median age of 83 and 52.8% were male. A total of 410 patients had a PPIs prescription, 358 (87.3%) were long-term PPIs-users and 52 (12.7%) were recent PPIs-users. Among PPIs-users, 163 (39.8%) patients developed severe COVID-19 versus 113 (26.7%) in PPIs-non users (odds ratio (OR) = 1.59 [1.18-2.14]; P < 0.05). Moreover, the double dose PPI-users had a higher risk of developing severe COVID-19 (OR = 3.36 [1.17-9.66]; P < 0.05) than the full dose PPI-users (OR = 2.15 [1.22-3.76]; P < 0.05) and the half dose PPI-users (OR = 1.64 [1.13-2.37]; P < 0.05).

CONCLUSION

Our study reports evidence that the use of PPIs was associated with an increased risk of severe COVID-19 in older people.

Precision nutrition to reset virus-induced human metabolic reprogramming and dysregulation (HMRD) in long-COVID

SARS-CoV-2, the etiological agent of COVID-19, is devoid of any metabolic capacity; therefore, it is critical for the viral pathogen to hijack host cellular metabolic machinery for its replication and propagation. This single-stranded RNA virus with a 29.9 kb genome encodes 14 open reading frames (ORFs) and initiates a plethora of virus-host protein-protein interactions in the human body. These extensive viral protein interactions with host-specific cellular targets could trigger severe human metabolic reprogramming/dysregulation (HMRD), a rewiring of sugar-, amino acid-, lipid-, and nucleotide-metabolism(s), as well as altered or impaired bioenergetics, immune dysfunction, and redox imbalance in the body. In the infectious process, the viral pathogen hijacks two major human receptors, angiotensin-converting enzyme (ACE)-2 and/or neuropilin (NRP)-1, for initial adhesion to cell surface; then utilizes two major host proteases, TMPRSS2 and/or furin, to gain cellular entry; and finally employs an endosomal enzyme, cathepsin L (CTSL) for fusogenic release of its viral genome. The virus-induced HMRD results in 5 possible infectious outcomes: asymptomatic, mild, moderate, severe to fatal episodes; while the symptomatic acute COVID-19 condition could manifest into 3 clinical phases: (i) hypoxia and hypoxemia (Warburg effect), (ii) hyperferritinemia ('cytokine storm'), and (iii) thrombocytosis (coagulopathy). The mean incubation period for COVID-19 onset was estimated to be 5.1 days, and most cases develop symptoms after 14 days. The mean viral clearance times were 24, 30, and 39 days for acute, severe, and ICU-admitted COVID-19 patients, respectively. However, about 25-70% of virus-free COVID-19 survivors continue to sustain virus-induced HMRD and exhibit a wide range of symptoms that are persistent, exacerbated, or new 'onset' clinical incidents, collectively termed as post-acute sequelae of COVID-19 (PASC) or long COVID. PASC patients experience several debilitating clinical condition(s) with >200 different and overlapping symptoms that may last for weeks to months. Chronic PASC is a cumulative outcome of at least 10 different HMRD-related pathophysiological mechanisms involving both virus-derived virulence factors and a multitude of innate host responses. Based on HMRD and virus-free clinical impairments of different human organs/systems, PASC patients can be categorized into 4 different clusters or sub-phenotypes: sub-phenotype-1 (33.8%) with cardiac and renal manifestations; sub-phenotype-2 (32.8%) with respiratory, sleep and anxiety disorders; sub-phenotype-3 (23.4%) with skeleto-muscular and nervous disorders; and sub-phenotype-4 (10.1%) with digestive and pulmonary dysfunctions. This narrative review elucidates the effects of viral hijack on host cellular machinery during SARS-CoV-2 infection, ensuing detrimental effect(s) of virus-induced HMRD on human metabolism, consequential symptomatic clinical implications, and damage to multiple organ systems; as well as chronic pathophysiological sequelae in virus-free PASC patients. We have also provided a few evidence-based, human randomized controlled trial (RCT)-tested, precision nutrients to reset HMRD for health recovery of PASC patients.

Vitamin B12 Hypersensitivity: A Retrospective Multicenter Study

BACKGROUND

Vitamin B12 (Vit B12) deficiency affects approximately 20% of those above the age of 60 years in the United Kingdom and United States. If untreated, it leads to detrimental health outcomes.

OBJECTIVE

To investigate a cohort of patients with Vit B12 hypersensitivity (VB12H) referred to 3 UK allergy centers and design a pathway for the investigation of VB12H.

METHODS

A total of 29 patients seen between 2014 and 2022 underwent skin prick testing (1 mg/mL) with cyanocobalamin (CC) and hydroxycobalamin (HC) and intradermal testing (0.1 and 0.01 mg/mL). Patients with negative skin tests underwent a Vit B12 drug provocation test (DPT) with either the index or the alternative drug.

RESULTS

Of 29 patients, 18 (62%) presented with immediate VB12H. Eight experienced anaphylaxis (4 to HC and 4 to CC) and had positive skin tests to the index drug. One patient reacted to oral and 7 patients to injectable Vit B12. Seven patients sensitized to one form of Vit B12-tolerated DPT with an alternative Vit B12. One patient with immediate VB12H reacted to polyethylene glycol (PEG) in oral cobalamin. Of 29 patients, 8 presented with delayed hypersensitivity reaction; 4 patients tolerated the intramuscular index formulation, whereas 2 patients tolerated the per oral formulation. One patient presented with symptoms consistent with symmetrical drug-related intertriginous and flexural exanthema. Three patients were referred because of cobalt allergy.

CONCLUSION

Confirmed VB12H is rare. We propose a comprehensive evaluation protocol that includes Vit B12 skin tests and considers PEG allergy in patients presenting with VB12H.

COVID-19 in patients with anemia and haematological malignancies: risk factors, clinical guidelines, and emerging therapeutic approaches

Extensive research in countries with high sociodemographic indices (SDIs) to date has shown that coronavirus disease 2019 (COVID-19) may be directly associated with more severe outcomes among patients living with haematological disorders and malignancies (HDMs). Because individuals with moderate to severe immunodeficiency are likely to undergo persistent infections, shed virus particles for prolonged periods, and lack an inflammatory or abortive phase, this represents an overall risk of morbidity and mortality from COVID-19. In cases suffering from HDMs, further investigation is needed to achieve a better understanding of triviruses and a group of related variants in patients with anemia and HDMs, as well as their treatment through vaccines, drugs, and other methods. Against this background, the present study aimed to delineate the relationship between HDMs and the novel COVID-19, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Besides, effective treatment options for HDM cases were further explored to address this epidemic and its variants. Therefore, learning about how COVID-19 manifests in these patients, along with exploiting the most appropriate treatments, may lead to the development of treatment and care strategies by clinicians and researchers to help patients recover faster. Video Abstract.

Significance of Vitamin Supplementation in Reducing the Severity of COVID-19

Coronavirus disease-19 (COVID-19), a serious pandemic due to the SARS-CoV-2 virus infection, caused significant lockdowns, healthcare shortages, and deaths worldwide. The infection leads to an uncontrolled systemic inflammatory response causing severe respiratory distress and multiple-organ failure. Quick development of several vaccines efficiently controlled the spread of COVID-19. However, the rise of various new subvariants of COVID-19 demonstrated some concerns over the efficacy of existing vaccines. Currently, better vaccines to control these variants are still under development as several new subvariants of COVID-19, such as omicron BA-4, BA-5, and BF-7 are still impacting the world. Few antiviral treatments have been shown to control COVID-19 symptoms. Further, control of COVID-19 symptoms has been explored with many natural and synthetic adjuvant compounds in hopes of treating the deadly and contagious disease. Vitamins have been shown to modulate the immune system, function as antioxidants, and reduce the inflammatory response. Recent studies have investigated the potential role of vitamins, specifically vitamins A, B, C, D, and E, in reducing the immune and inflammatory responses and severity of the complication. In this brief article, we discussed our current understanding of the role of vitamins in controlling COVID-19 symptoms and their potential use as adjuvant therapy.

Potent Antiviral Activity of Vitamin B12 against Severe Acute Respiratory Syndrome Coronavirus 2, Middle East Respiratory Syndrome Coronavirus, and Human Coronavirus 229E

Repurposing vitamins as antiviral supporting agents is a rapid approach used to control emerging viral infections. Although there is considerable evidence supporting the use of vitamin supplementation in viral infections, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the specific role of each vitamin in defending against coronaviruses remains unclear. Antiviral activities of available vitamins on the infectivity and replication of human coronaviruses, namely, SARS-CoV-2, Middle East respiratory syndrome coronavirus (MERS-CoV), and human coronavirus 229E (HCoV-229E), were investigated using in silico and in vitro studies. We identified potential broad-spectrum inhibitor effects of Hydroxocobalamin and Methylcobalamin against the three tested CoVs. Cyanocobalamin could selectively affect SARS-CoV-2 but not MERS-CoV and HCoV-229E. Methylcobalamin showed significantly higher inhibition values on SARS-CoV-2 compared with Hydroxocobalamin and Cyanocobalamin, while Hydroxocobalamin showed the highest potent antiviral activity against MERS-CoV and Cyanocobalamin against HCoV-229E. Furthermore, in silico studies were performed for these promising vitamins to investigate their interaction with SARS-CoV-2, MERS-CoV, and HCoV-229E viral-specific cell receptors (ACE2, DPP4, and hAPN protein, respectively) and viral proteins (S-RBD, 3CL pro, RdRp), suggesting that Hydroxocobalamin, Methylcobalamin, and Cyanocobalamin may have significant binding affinity to these proteins. These results show that Methylcobalamin may have potential benefits for coronavirus-infected patients.

Treatment of 95 post-Covid patients with SSRIs

After Covid-19 infection, 12.5% develops post-Covid-syndrome (PCS). Symptoms indicate numerous affected organ systems. After a year, chronic fatigue, dysautonomia and neurological and neuropsychiatric complaints predominate. In this study, 95 PCS patients were treated with selective serotonin reuptake inhibitors (SSRIs). This study used an exploratory questionnaire and found that two-thirds of patients had a reasonably good to strong response on SSRIs, over a quarter of patients had moderate response, while 10% reported no response. Overall, patients experienced substantial improved well-being. Brainfog and sensory overload decreased most, followed by chronic fatigue and dysautonomia. Outcomes were measured with three different measures that correlated strongly with each other. The response to SSRIs in PCS conditions was explained by seven possible neurobiological mechanisms based on recent literature on PCS integrated with already existing knowledge. Important for understanding these mechanisms is the underlying biochemical interaction between various neurotransmitter systems and parts of the immune system, and their dysregulation in PCS. The main link appears to be with the metabolic kynurenine pathway (KP) which interacts extensively with the immune system. The KP uses the same precursor as serotonin: tryptophan. The KP is overactive in PCS which maintains inflammation and which causes a lack of tryptophan. Finally, potential avenues for future research to advance this line of clinical research are discussed.

Prevalence of Cobalt in the Environment and Its Role in Biological Processes

Cobalt (Co) is an essential trace element for humans and other animals, but high doses can be harmful to human health. It is present in some foods such as green vegetables, various spices, meat, milk products, seafood, and eggs, and in drinking water. Co is necessary for the metabolism of human beings and animals due to its key role in the formation of vitamin B12, also known as cobalamin, the biological reservoir of Co. In high concentrations, Co may cause some health issues such as vomiting, nausea, diarrhea, bleeding, low blood pressure, heart diseases, thyroid damage, hair loss, bone defects, and the inhibition of some enzyme activities. Conversely, Co deficiency can lead to anorexia, chronic swelling, and detrimental anemia. Co nanoparticles have different and various biomedical applications thanks to their antioxidant, antimicrobial, anticancer, and antidiabetic properties. In addition, Co and cobalt oxide nanoparticles can be used in lithium-ion batteries, as a catalyst, a carrier for targeted drug delivery, a gas sensor, an electronic thin film, and in energy storage. Accumulation of Co in agriculture and humans, due to natural and anthropogenic factors, represents a global problem affecting water quality and human and animal health. Besides the common chelating agents used for Co intoxication, phytoremediation is an interesting environmental technology for cleaning up soil contaminated with Co. The occurrence of Co in the environment is discussed and its involvement in biological processes is underlined. Toxicological aspects related to Co are also examined in this review.

Precision management of post-COVID pain: An evidence and clinical-based approach

Background Pain after a SARS-CoV-2 acute infection (post-COVID pain) is becoming a new healthcare emergency but remains underestimated and most likely undertreated due to a lack of recognition of the phenomenon and knowledge of the underlying pain mechanisms. Evidence supporting any particular treatment approach for the management of post-COVID pain is lacking. Large variability in the patient response to any standard pain treatments is clinically observed, which has led to calls for a personalized, tailored approach to treating patients with chronic post-COVID pain (i.e. 'precision pain medicine'). Applying the global concerted action towards precision medicine to post-COVID pain could help guide clinical decision-making and aid in more effective treatments. Methods The current position paper discusses factors to be considered by clinicians for managing post-COVID pain ranging from identification of the pain phenotype to genetic consideration. Results The ability of clinicians to phenotype post-COVID pain into nociceptive, neuropathic, nociplastic or mixed type is suggested as the first step to better planification of a treatment programme. Further, the consideration of other factors, such as gender, comorbidities, treatments received at the acute phase of infection for onset-associated COVID-19 symptoms, factors during hospitalization or the presence of emotional disturbances should be implemented into a treatment programme. Conclusions Accordingly, considering these factors, management of post-COVID pain should include multimodal pharmacological and non-pharmacological modalities targeting emotional/cognitive aspects (i.e. psychological and/or coping strategies), central sensitization-associated mechanisms (i.e. pain neuroscience education), exercise programmes as well as lifestyle interventions (e.g. nutritional support and sleep management). SIGNIFICANCE: This position paper presents an evidence-based clinical reasoning approach for precision management of post-COVID pain.

COVID-19 as a polymorphic inflammatory spectrum of diseases: a review with focus on the brain

There appear to be huge variations and aberrations in the reported data in COVID-19 2 years now into the pandemic. Conflicting data exist at almost every level and also in the reported epidemiological statistics across different regions. It is becoming clear that COVID-19 is a polymorphic inflammatory spectrum of diseases, and there is a wide range of inflammation-related pathology and symptoms in those infected with the virus. The host's inflammatory response to COVID-19 appears to be determined by genetics, age, immune status, health status and stage of disease. The interplay of these factors may decide the magnitude, duration, types of pathology, symptoms and prognosis in the spectrum of COVID-19 disorders, and whether neuropsychiatric disorders continue to be significant. Early and successful management of inflammation reduces morbidity and mortality in all stages of COVID-19.

Evaluation of serum vitamin B12 levels in patients with COVID-19 infection: A case-control study

Background

COVID-19 disease affects the respiratory and cardiovascular systems. Vitamin B12 has been associated with A1AT, one of the protective factors of lung tissue, and homocysteine among the cardiovascular risk factors. Therefore we suggest that low vitamin B12 levels are associated with a disposition to COVID-19 infection. This study aims to determine whether there is a relationship between COVID-19 infection and serum vitamin B12 levels.

Methods

This research is a case-control study. Seventy-six people with COVID-19 constituted the case group. Seventy-six people without COVID-19 formed the control group. Vitamin B12 and homocysteine levels of 152 patients included in the study were analyzed.

Results

The odds ratio for vitamin B12 was 0.99 (0.978-0.995). When the value of the vitamin B12 variable decreases by one unit, the risk of COVID-19 increases by 1%. The odds ratio for homocysteine was 1.81 (1.414-2.325). When the value of the homocysteine variable increases by one unit, the risk of COVID-19 increases by 1.81 times. According to ROC analysis, when serum vitamin B12 is below 222.5 ng/L and homocysteine is above 13.7 mmol/L, it may increase the risk of COVID-19.

Conclusions

We suggest that patients with low vitamin B12 levels and high homocysteine levels are more severely affected by COVID-19 infection.

The Prophylactic Effect of Vitamin C and Vitamin B12 against Ultraviolet-C-Induced Hepatotoxicity in Male Rats

Ultraviolet C (UVC) devices are an effective means of disinfecting surfaces and protecting medical tools against various microbes, including coronavirus. Overexposure to UVC can induce oxidative stress, damage the genetic material, and harm biological systems. This study investigated the prophylactic efficacy of vitamin C and B12 against hepatotoxicity in UVC-intoxicated rats. Rats were irradiated with UVC (725.76, 967.68, and 1048.36 J/cm²) for 2 weeks. The rats were pretreated with the aforementioned antioxidants for two months before UVC irradiation. The prophylactic effect of vitamins against UVC hepatotoxicity was evaluated by monitoring the alteration of liver enzyme activities, antioxidant status, apoptotic and inflammatory markers, DNA fragmentation, and histological and ultrastructural alterations. Rats exposed to UVC showed a significant increase in liver enzymes, oxidant-antioxidant balance disruption, and increased hepatic inflammatory markers (TNF-α, IL-1β, iNOS, and IDO-1). Additionally, obvious over-expression of activated caspase-3 protein and DNA fragmentation were detected. Histological and ultrastructural examinations verified the biochemical findings. Co-treatment with vitamins ameliorated the deviated parameters to variable degrees. In conclusion, vitamin C could alleviate UVC-induced hepatotoxicity more than vitamin B12 by diminishing oxidative stress, inflammation, and DNA damage. This study could provide a reference for the clinical practice of vitamin C and B12 as radioprotective for workers in UVC disinfectant areas.

Multi-omics blood atlas reveals unique features of immune and platelet responses to SARS-CoV-2 Omicron breakthrough infection

Although host responses to the ancestral SARS-CoV-2 strain are well described, those to the new Omicron variants are less resolved. We profiled the clinical phenomes, transcriptomes, proteomes, metabolomes, and immune repertoires of >1,000 blood cell or plasma specimens from SARS-CoV-2 Omicron patients. Using in-depth integrated multi-omics, we dissected the host response dynamics during multiple disease phases to reveal the molecular and cellular landscapes in the blood. Specifically, we detected enhanced interferon-mediated antiviral signatures of platelets in Omicron-infected patients, and platelets preferentially formed widespread aggregates with leukocytes to modulate immune cell functions. In addition, patients who were re-tested positive for viral RNA showed marked reductions in B cell receptor clones, antibody generation, and neutralizing capacity against Omicron. Finally, we developed a machine learning model that accurately predicted the probability of re-positivity in Omicron patients. Our study may inspire a paradigm shift in studying systemic diseases and emerging public health concerns.

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.

Riboflavin Targets the Cellular Metabolic and Ribosomal Pathways of Candida albicans In Vitro and Exhibits Efficacy against Oropharyngeal Candidiasis

Oropharyngeal candidiasis (OPC), which has a high incidence in immunocompromised and denture stomatitis patients, is commonly caused by Candida albicans infection and in some cases develops into disseminated candidiasis throughout the throat and esophagus, resulting in high mortality. New drugs are needed to combat OPC because of the limited treatment options currently available and increasing resistance to existing drugs. Here, we confirmed that riboflavin (RF), a cofactor of flavin adenine mononucleotide and flavin adenine dinucleotide, has broad-spectrum anti-Candida activity. The formation of C. albicans hyphae and biofilm was inhibited by RF. Mechanistically, RF disrupted membrane and cell wall integrity, as well as promoting reactive oxygen species and pyruvate accumulation. Furthermore, RF targeted multiple essential pathways via functional disruption of thiamine and RF metabolic pathways, central carbon metabolism, and ribosome metabolism. Similar to the results in vitro, the inhibitory effect of RF on C. albicans hyphae was confirmed in a mouse model of OPC. Moreover, after 5 consecutive days of intraperitoneal injection, RF exhibited therapeutic efficacy, as demonstrated by phenotype investigation, the fungal burden, and histopathological analysis. These findings revealed that RF exerts a multifaceted anti-Candida effect and has potential benefits in the treatment of OPC. IMPORTANCE Candida species are common pathogens in fungal infections, causing mucosal infection and invasive infection in immunodeficient patients. Given the limited classes of drugs and resistance to these drugs, new antifungal agents need to be developed. Drug repurposing is a potential method for antifungal drug development. This study demonstrated that riboflavin (RF) exhibited broad-spectrum anti-Candida activity. RF affected multiple targets involving the membrane and cell wall integrity, the accumulation of reactive oxygen species and pyruvate, and the altered metabolic pathways in C. albicans. Moreover, RF exhibited efficacy in the treatment of C. albicans in an oropharyngeal candidiasis mouse model. Taken together, the antifungal activity and the promising clinical application of RF were highlighted.

[Vitamins and Immune System Health]

Keeping the immune system healthy forms an effective way to fight infections. Past experience has shown that, in addition to effective interventions including vaccination, drug therapy, and non-pharmaceutical intervention (NPI), dietary nutrition and mental health are also key factors in maintaining immune system health and combating emerging and sudden outbreaks of infections. As the main dietary nutrients, vitamins are active regulators of the immune response and exert a critical impact on the immunity of the human body. Vitamin deficiency causes increased levels of inflammation and decreased immunity, which usually starts in the oral tissues. Appropriate vitamin supplementation can help the body optimize immune function, enhance oral immunity, and reduce the negative impact of pathogen infection on the human body, which makes it a feasible, effective, and universally applicable anti-infection solution. This review focuses on the immunomodulatory effects of vitamin A, B, C, D, and E and proposes that an omics-based new systemic approach will lead to a breakthrough of the limitations in traditional single-factor single-pathway research and provide the direction for the basic and applied research of vitamin immune regulation and anti-infection in all aspects.

Relationship between high dose intake of vitamin B12 and glaucoma: Evidence from NHANES 2005-2008 among United States adults

Objective

Glaucoma has currently become the second leading cause of blindness in the world. Serum vitamin B12 level has been found to be involved in the development and progression of glaucoma. We performed the present study to confirm this association.

Methods

This cross-sectional study included 594 participants aged 40 years and older in the National Health and Nutrition Examination Survey (NHANES) from 2005 to 2008. Retinal imaging was performed using the Ophthalmic Digital Imaging system (Retinography) to assess the retina for the presence of features of glaucomatous lesions. Logistic regression models were used to assess the association between dietary vitamin intake and glaucoma.

Results

After screening, 594 subjects were finally included. Among all vitamin intakes, we observed significant differences between the two groups for vitamin B12 intake (5.93 vs. 4.77 mg, p = 0.033). According to the logistic regression results, the intake of vitamin B12 was significantly positively associated with glaucoma (model 1: OR = 1.078, 95% CI = 1.019-1.141; model 2: OR = 1.092, 95% CI = 1.031-1.158; model 3: OR = 1.092, 95% CI = 1.029-1.158). After performing a quantile regression, we observed a significant positive association between vitamin B12 intake and incident glaucoma in the fourth quartile (model 1: OR = 1.133, 95% CI = 1.060-1.210; model 2: OR = 1.141, 95% CI = 1.072-1.215; model 3: OR = 1.146, 95% CI = 1.071-1.226).

Conclusions

Therefore, the above results, high-dose intake of vitamin B12 may promote the development of glaucoma.

Advances of Cobalt Nanomaterials as Anti-Infection Agents, Drug Carriers, and Immunomodulators for Potential Infectious Disease Treatment

Infectious diseases remain the most serious public health issue, which requires the development of more effective strategies for infectious control. As a kind of ultra-trace element, cobalt is essential to the metabolism of different organisms. In recent decades, nanotechnology has attracted increasing attention worldwide due to its wide application in different areas, including medicine. Based on the important biological roles of cobalt, cobalt nanomaterials have recently been widely developed for their attractive biomedical applications. With advantages such as low costs in preparation, hypotoxicity, photothermal conversion abilities, and high drug loading ability, cobalt nanomaterials have been proven to show promising potential in anticancer and anti-infection treatment. In this review, we summarize the characters of cobalt nanomaterials, followed by the advances in their biological functions and mechanisms. More importantly, we emphatically discuss the potential of cobalt nanomaterials as anti-infectious agents, drug carriers, and immunomodulators for anti-infection treatments, which might be helpful to facilitate progress in future research of anti-infection therapy.

Central retinal vein occlusion post ChAdOx1 nCoV-19 vaccination - can it be explained by the two-hit hypothesis?

PURPOSE

To report a case of central retinal vein occlusion (CRVO) seven days following the first dose of ChAdOx1 nCoV-19 vaccine and propose a hypothesis for the possible underlying pathogenesis.

OBSERVATION

A 31-year-old male presented with CRVO with cystoid macular edema, one week after receiving his first ChAdOx1 nCoV-19 vaccine dose. Apart from mild hyperhomocysteinemia, no major thrombophilic or systemic risk factors were found. Anti-platelet factor 4 antibodies, specific for vaccine-induced immune thrombotic thrombocytopenia, were also negative. However, he tested strongly positive (> 250 U/mL) for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) IgG spike antibodies, 2 weeks post the first dose - suggestive of a prior subclinical infection.

CONCLUSION

COVID-19 is known to be associated with an altered host one-carbon metabolism resulting in hyperhomocysteinemia. We hypothesize that a prior subclinical infection with COVID-19, the first hit, may have led to hyperhomocysteinemia in our patient and vaccination must have been the second hit that triggered the thrombotic event. Further studies, including correlation of thrombotic complications with IgG antibody titres post-vaccination, are essential in order to better understand the pathogenesis of such events.

What Are the Effects of Vitamin A Oral Supplementation in the Prevention and Management of Viral Infections? A Systematic Review of Randomized Clinical Trials

Vitamin A (VA) deficiency is associated with increased host susceptibility to infections, but evidence on its role in the prevention and management of viral infections is still lacking. This review aimed at summarizing the effects of VA supplementation against viral infections to support clinicians in evaluating supplemental treatments. PubMed, Scopus, and Web of Science were searched. Randomized clinical trials comparing the direct effects of VA oral supplementation in any form vs. placebo or standard of care in the prevention and/or management of confirmed viral infections in people of any age were included. A narrative synthesis of the results was performed. The revised Cochrane Risk-Of-Bias tool was used to assess quality. Overall, 40 articles of heterogeneous quality were included. We found data on infections sustained by Retroviridae (n = 17), Caliciviradae (n = 2), Flaviviridae (n = 1), Papillomaviridae (n = 3), Pneumoviridae (n = 4), and Paramyxoviridae (n = 13). Studies were published between 1987 and 2017 and mostly conducted in Africa. The findings were heterogeneous across and within viral families regarding virological, immunological, and biological response, and no meaningful results were found in the prevention of viral infections. For a few diseases, VA-supplemented individuals had a better prognosis and improved outcomes, including clearance of HPV lesions or reduction in some measles-related complications. The effects of VA oral supplementation seem encouraging in relation to the management of a few viral infections. Difference in populations considered, variety in recruitment and treatment protocols might explain the heterogeneity of the results. Further investigations are needed to better identify the benefits of VA administration.

The potential role of ischaemia-reperfusion injury in chronic, relapsing diseases such as rheumatoid arthritis, Long COVID, and ME/CFS: evidence, mechanisms, and therapeutic implications

Ischaemia–reperfusion (I–R) injury, initiated via bursts of reactive oxygen species produced during the reoxygenation phase following hypoxia, is well known in a variety of acute circumstances. We argue here that I–R injury also underpins elements of the pathology of a variety of chronic, inflammatory diseases, including rheumatoid arthritis, ME/CFS and, our chief focus and most proximally, Long COVID. Ischaemia may be initiated via fibrin amyloid microclot blockage of capillaries, for instance as exercise is started; reperfusion is a necessary corollary when it finishes. We rehearse the mechanistic evidence for these occurrences here, in terms of their manifestation as oxidative stress, hyperinflammation, mast cell activation, the production of marker metabolites and related activities. Such microclot-based phenomena can explain both the breathlessness/fatigue and the post-exertional malaise that may be observed in these conditions, as well as many other observables. The recognition of these processes implies, mechanistically, that therapeutic benefit is potentially to be had from antioxidants, from anti-inflammatories, from iron chelators, and via suitable, safe fibrinolytics, and/or anti-clotting agents. We review the considerable existing evidence that is consistent with this, and with the biochemical mechanisms involved.

Fetal Brain Damage during Maternal COVID-19: Emerging Hypothesis, Mechanism, and Possible Mitigation through Maternal-Targeted Nutritional Supplementation

The recent outbreak of the novel Coronavirus (SARS-CoV-2 or CoV-2) pandemic in 2019 and the risk of CoV-2 infection during pregnancy led the scientific community to investigate the potential negative effects of Coronavirus infection on pregnancy outcomes and fetal development. In particular, as CoV-2 neurotropism has been demonstrated in adults, recent studies suggested a possible risk of fetal brain damage and fetal brain development impairment, with consequent psychiatric manifestations in offspring of mothers affected by COronaVIrus Disease (COVID) during pregnancy. Through the understanding of CoV-2’s pathogenesis and the pathways responsible for cell damage, along with the available data about neurotropic virus attitudes, different strategies have been suggested to lower the risk of neurologic disease in newborns. In this regard, the role of nutrition in mitigating fetal damages related to oxidative stress and the inflammatory environment during viral infection has been investigated, and arginine, n3PUFA, vitamins B1 and B9, choline, and flavonoids were found to be promising in and out of pregnancy. The aim of this review is to provide an overview of the current knowledge on the mechanism of fetal brain damage and the impact of nutrition in reducing inflammation related to worse neurological outcomes in the context of CoV-2 infections during pregnancy.

Genetically Predicted Circulating Concentrations of Micronutrients and COVID-19 Susceptibility and Severity: A Mendelian Randomization Study

Background

Coronavirus disease 2019 (COVID-19) is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) which since 2019 has caused over 5 million deaths to date. The pathogenicity of the virus is highly variable ranging from asymptomatic to fatal. Evidence from experimental and observational studies suggests that circulating micronutrients may affect COVID-19 outcomes.

Objectives

To complement and inform observational studies, we investigated the associations of genetically predicted concentrations of 12 micronutrients (β-carotene, calcium, copper, folate, iron, magnesium, phosphorus, selenium, vitamin B-6, vitamin B-12, vitamin D, and zinc) with SARS-CoV-2 infection risk and COVID-19 severity using Mendelian randomization (MR).

Methods

Two-sample MR was conducted using 87,870 individuals of European descent with a COVID-19 diagnosis and 2,210,804 controls from the COVID-19 host genetics initiative. Inverse variance-weighted MR analyses were performed with sensitivity analyses to assess the impact of potential violations of MR assumptions.

Results

Compared to the general population, nominally significant associations were noted for higher genetically predicted vitamin B-6 (Odds ratio per standard deviation [OR_SD]: 1.06; 95% confidence interval [CI]: 1.00, 1.13; p-value = 0.036) and lower magnesium concentrations (OR_SD: 0.33; 95%CI: 0.11, 0.96; P = 0.042) with COVID-19 infection risk. However, the association for magnesium was not consistent in some sensitivity analyses, and sensitivity analyses could not be performed for vitamin B-6 as only two genetic instruments were available. Genetically predicted levels of calcium, folate, β-carotene, copper, iron, vitamin B-12, vitamin D, selenium, phosphorus, or zinc were not associated with the outcomes from COVID-19 disease.

Conclusion

These results, though based only on genetically predicated circulating micronutrient concentrations, provide scant evidence for possible associations of micronutrients with COVID-19 outcomes.

Therapeutic Vitamin D Supplementation Following COVID-19 Diagnosis: Where Do We Stand?—A Systematic Review

Vitamin D has known immunomodulatory activity and multiple indications exist supporting its potential use against SARS-CoV-2 infection in the setting of the current pandemic. The purpose of this systematic review is to examine the efficacy of vitamin D administered to adult patients following COVID-19 diagnosis in terms of length of hospital stay, intubation, ICU admission and mortality rates. Therefore, PubMed and Scopus databases were searched for original articles referring to the aforementioned parameters. Of the 1376 identified studies, eleven were finally included. Vitamin D supplements, and especially calcifediol, were shown to be useful in significantly reducing ICU admissions and/or mortality in four of the studies, but not in diminishing the duration of hospitalization of COVID-19 patients. Due to the large variation in vitamin D supplementation schemes no absolute conclusions can be drawn until larger randomized controlled trials are completed. However, calcifediol administered to COVID-19 patients upon diagnosis represents by far the most promising agent and should be the focus of upcoming research efforts.