Vitamin A, infection, and immune function

Apo-12'-capsorubinal exhibits anti-inflammatory effects and activates nuclear factor erythroid 2-related factor 2 in RAW264.7 macrophages

Apocarotenoids have short carbon chain structures cleaved at a polyene-conjugated double bond. They can be biosynthesized in plants and microorganisms. Animals ingest carotenoids through food and then metabolize them into apocarotenoids. Although several apocarotenoids have been identified in the body, their precise health functions are still poorly understood. This study investigated the anti-inflammatory activities of apo-12'-capsorubinal in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. It was confirmed that apo-12'-capsorubinal was not cytotoxic to the macrophages at the concentrations tested. Apo-12'-capsorubinal treatment led to a marked downregulation of interleukin (IL)-6 protein and Il6 mRNA levels. This apocarotenoid exhibited more potent inhibitory effects than its parent carotenoids, capsanthin and capsorubin. Furthermore, apo-12'-capsorubinal, but not its parent carotenoids, promoted the nuclear accumulation of nuclear factor erythroid 2-related factor 2 (Nrf2) and upregulated the expression of Nrf2-target genes, such as heme oxygenase 1 (HO-1) and NAD(P)H:quinone oxidoreductase 1 (NQO-1), in a dose-dependent manner. Furthermore, a comparison using apo-12'-zeaxanthinal and 7,8-dihydro-8-oxo-apo-12'-zeaxanthinal revealed that the α, β-unsaturated carbonyl group on the polyene linear chain mediated the enhanced nuclear Nrf2 translocation, HO-1 expression, and inhibition of IL-6 production. In contrast, apo-12'-mytiloxanthinal, which harbored a hydroxyl group at C-8 of apo-12'-capsorubinal, did not exhibit any of these activities. These results indicated that the β carbon of the α, β-unsaturated carbonyl group in the linear part of the polyene chain is crucial to the Nrf2-activating and anti-inflammatory effects of apo-12'-capsorubinal. This study will advance our knowledge of the physiological significance of xanthophyll-derived apocarotenoids and their potential use as nutraceuticals and pharmaceuticals.

The association between serum vitamin A concentrations and virus hepatitis among U.S. adults from the NHANES database: a cross-sectional study

Objective

According to the present study, the relationship between vitamin A (VA) levels and hepatitis virus carriage has been unclear and controversial. This study aimed to determine the potential relationship between serum VA levels and viral hepatitis and to provide ideas for future clinical treatments.

Methods

A cross-sectional study was performed using the 2005-2006 and 2017-2018 National Health and Nutrition Examination Survey (NHANES) datasets. Multiple linear regression and logistic regression were adopted to analyze the association between serological hepatitis B surface antigen (HBsAg) or hepatitis C RNA (HCV-RNA) positivity and VA levels. There were 5,351 HBsAg-related responders and 242 HCV-RNA-related responders, including 52 HBsAg (+) and 104 HCV-RNA (+) responders.

Results

Compared with HBsAg (-) and HCV-RNA (-) respondents, HBsAg (+) and HCV-RNA (+) respondents tended to have lower serum VA levels, respectively [1.63 (1.33 ~ 2.01) vs. 1.92 (1.57 ~ 2.34), P < 0.001; 1.54 (1.25 ~ 1.83) vs. 1.78 (1.46 ~ 2.26), P < 0.001]. A greater percentage of responders in the subclinical VA deficiency (SVAD) group were HBsAg (+) and HCV-RNA (+) than were those in the normal VA (VAN) group [2.4% (9/374) vs. 0.9% (43/4977), p = 0.003; 61.5% (16/26) vs. 40.7% (88/215), p = 0.043]. According to the results of the multiple regression analyses of the different models, the serum VA concentration was negatively correlated with HBsAg (+) and HCV-RNA (+) status (β = -0.14, 95% CI = -0.30 to -0.01, p = 0.066; β = -0.29, 95% CI = -0.50 ~ -0.09, p = 0.005, respectively). Compared to those with SVAD, patients with VAN were less likely to be serologically HBsAg (+) or HCV-RNA (+) (OR = 0.53, 95% CI = 0.25 ~ 1.10, p = 0.089; OR = 0.39, 95% CI = 0.18 ~ 0.84, p = 0.016, respectively).

Conclusion

Our study provides evidence that patients who are HBsAg (+) or HCV-RNA (+) have a high incidence of SVAD. Moreover, HBsAg and HCV-RNA positivity are negatively correlated with VA levels, and patients with SVAD are more likely to carry HBsAg (+) or HCV-RNA (+). These findings suggest that the relationship between hepatitis viruses and vitamin A needs to be validated by more basic studies and clinical large-sample randomized controlled trials to provide ideas for new therapeutic targets.

Association of Candidate Single-Nucleotide Polymorphism Genotypes With Plasma and Skin Carotenoid Concentrations in Adults Provided a Lycopene-Rich Juice

BACKGROUND

Carotenoids are fat-soluble phytochemicals with biological roles, including ultraviolet protective functions in skin. Spectroscopic skin carotenoid measurements can also serve as a noninvasive biomarker for carotenoid consumption. Single-nucleotide polymorphisms (SNPs) in metabolic genes are associated with human plasma carotenoid concentrations; however, their relationships with skin carotenoid concentrations are unknown.

OBJECTIVES

The objective of this study was to determine the relationship between 13 candidate SNPs with skin and plasma carotenoid concentrations before and after a carotenoid-rich tomato juice intervention.

METHODS

In this randomized, controlled trial, participants (n = 80) were provided with lycopene-rich vegetable juice providing low (13.1 mg), medium (23.9 mg), and high (31.0 mg) daily total carotenoid doses for 8 wk. Plasma carotenoid concentrations were measured by high-pressure liquid chromatography, and skin carotenoid score was assessed by reflection spectroscopy (Veggie Meter) at baseline and the end-of-study time point. Thirteen candidate SNPs in 5 genes (BCO1, CD36, SCARB1, SETD7, and ABCA1) were genotyped from blood using PCR-based assays. Mixed models tested the effects of the intervention, study time point, interaction between intervention and study time point, and SNP genotype on skin and plasma carotenoids throughout the study. Baseline carotenoid intake, body mass index, gender, and age are covariates in all models.

RESULTS

The genotype of CD36 rs1527479 (P = 0.0490) was significantly associated with skin carotenoid concentrations when baseline and the final week of the intervention were evaluated. Genotypes for BCO1 rs7500996 (P = 0.0067) and CD36 rs1527479 (P = 0.0018) were significant predictors of skin carotenoid concentrations in a combined SNP model.

CONCLUSIONS

These novel associations between SNPs and skin carotenoid concentrations expand on the understanding of how genetic variation affects interindividual variation in skin carotenoid phenotypes in humans. This trial was registered at clinicaltrials.gov as NCT03202043.

Xeropthalmia and optic neuropathy secondary to ARFID: a case report

BACKGROUND

Patients with avoidant/restrictive food intake disorder (ARFID) commonly present with loss of weight or faltering growth in the setting of poor nutrition. However, patients with ARFID can present with micronutrient deficiencies without weight loss. In patients with ARFID, clinicians should be vigilant for micronutrient deficiencies and their presentations.

CASE PRESENTATION

We report a unique case of ARFID in a twelve-year-old girl, who developed micronutrient deficiencies and presented with acute visual loss with a preceding history of impaired night vision. Ophthalmic examination revealed xerophthalmia and bilateral optic neuropathy. Investigations showed severe Vitamin A and folate deficiencies which accounted for her clinical findings. In addition, she was also found to have low Vitamin B12, copper, and Vitamin D levels. She had a history of selective eating from a young age with a diet consisting largely of carbohydrates, with no regular intake of meat, dairy, fruit and vegetables. This was not driven by weight or body image concerns. The patient's symptoms improved significantly with appropriate vitamin replacement and continued multidisciplinary care.

CONCLUSIONS

This report describes a patient with ARFID presenting with visual complaints. In this case, the selective eating behaviours resulted in xeropthalmia and optic neuropathy. Micronutrient deficiencies are uncommon in developed countries. When these deficiencies are suspected, eating disorders, such as ARFID, should be considered. Similarly, clinicians caring for patients with restrictive eating disorders including ARFID should be familiar with the clinical presentations of various micronutrient deficiencies and consider evaluation and treatment for micronutrient deficiencies when clinically indicated.

Dietary patterns and micronutrients in respiratory infections including COVID-19: a narrative review

BACKGROUND

COVID-19 is a pandemic caused by nCoV-2019, a new beta-coronavirus from Wuhan, China, that mainly affects the respiratory system and can be modulated by nutrition.

METHODS

This review aims to summarize the current literature on the association between dietary intake and serum levels of micronutrients, malnutrition, and dietary patterns and respiratory infections, including flu, pneumonia, and acute respiratory syndrome, with a focus on COVID-19. We searched for relevant articles in various databases and selected those that met our inclusion criteria.

RESULTS

Some studies suggest that dietary patterns, malnutrition, and certain nutrients such as vitamins D, E, A, iron, zinc, selenium, magnesium, omega-3 fatty acids, and fiber may have a significant role in preventing respiratory diseases, alleviating symptoms, and lowering mortality rates. However, the evidence is not consistent and conclusive, and more research is needed to clarify the mechanisms and the optimal doses of these dietary components. The impact of omega-3 and fiber on respiratory diseases has been mainly studied in children and adults, respectively, and few studies have examined the effect of dietary components on COVID-19 prevention, with a greater focus on vitamin D.

CONCLUSION

This review highlights the potential of nutrition as a modifiable factor in the prevention and management of respiratory infections and suggests some directions for future research. However, it also acknowledges the limitations of the existing literature, such as the heterogeneity of the study designs, populations, interventions, and outcomes, and the difficulty of isolating the effects of single nutrients from the complex interactions of the whole diet.

Coccidiosis in Egg-Laying Hens and Potential Nutritional Strategies to Modulate Performance, Gut Health, and Immune Response

Avian coccidiosis, despite advancements in management, nutrition, genetics, and immunology, still remains the most impactful disease, imposing substantial economic losses to the poultry industry. Coccidiosis may strike any avian species, and it may be mild to severe, depending on the pathogenicity of Eimeria spp. and the number of oocysts ingested by the bird. Unlike broilers, low emphasis has been given to laying hens. Coccidiosis in laying hens damages the gastrointestinal tract and causes physiological changes, including oxidative stress, immunosuppression, and inflammatory changes, leading to reduced feed intake and a drastic drop in egg production. Several countries around the world have large numbers of hens raised in cage-free/free-range facilities, and coccidiosis has already become one of the many problems that producers have to face in the future. However, limited research has been conducted on egg-laying hens, and our understanding of the physiological changes following coccidiosis in hens relies heavily on studies conducted on broilers. The aim of this review is to summarize the effect of coccidiosis in laying hens to an extent and correlate it with the physiological changes that occur in broilers following coccidiosis. Additionally, this review tries to explore the nutritional strategies successfully used in broilers to mitigate the negative effects of coccidiosis in improving the gut health and performance of broilers and if they can be used in laying hens.

Pet Wellness and Vitamin A: A Narrative Overview

The health of companion animals, particularly dogs and cats, is significantly influenced by nutrition, with vitamins playing a crucial role. Vitamin A, in particular, is indispensable, with diverse roles ranging from vision to immune modulation and reproduction. Despite its importance, the metabolism and dietary requirements of vitamin A in companion animals remain complex and not fully understood. This review provides a comprehensive overview of the historical perspective, the digestion, the metabolism, the physiological roles, the deficiency, the excess, and the interactions with other micronutrients of vitamin A in companion animals. Additionally, it highlights future research directions and gaps in our understanding. Insights into the metabolism of vitamin A in companion animals, personalized nutrition strategies based on genetic variability, longitudinal studies tracking the status of vitamin A, and investigations into its immunomodulatory effects are crucial for optimizing pet health and wellness. Furthermore, understanding the stability and bioavailability of vitamin A in pet food formulations is essential for ensuring the provision of adequate micronutrients. Overall, this review underscores the importance of vitamin A in companion animal nutrition and the need for further research to enhance our understanding and to optimize dietary recommendations for pet health and well-being.

Effects of supplemental vitamin A on reproduction and antioxidative status of aged laying hens, and growth, blood indices and immunity of their offspring

The purpose of this investigation was to evaluate the impacts of vitamin A (VA) supplementation in feed at levels of 0 (control), 2,000, 4,000, 6,000, and 8,000 IU VA/kg diet on the reproductive efficiency and antioxidative properties of aged Sinai laying hens at 52 wk of age (n = 300 females and 30 males) in 6 replicates (10 females + 1 male/replicate). As well as blood biochemical indicators, carcass characteristics, growth performance, immunity, and the antioxidative status of their chicks. Results showed that diets supplemented with 2,000 or 6,000 IU/kg of VA increased fertility rate and decreased early embryonic mortality (P < 0.05). Increasing VA from 4,000 to 6,000 IU/kg significantly boosted hatchability rates. All VA levels significantly enhanced glutathione peroxidase (GPx) and reduced malondialdehyde (MDA) and late embryonic mortality. In the shell gland, dietary supplementation of 6,000 or 8,000 IU/kg of VA enhanced actions of GPx actions, catalase (CAT), and superoxide dismutase (SOD). In hatched chicks, all VA levels boosted (P < 0.05) hemoglobin, red blood cell count, and serum concentration of total proteins and IgA while decreasing eosinophils percentage and aspartate aminotransferase activity (AST) concentration. Dietary VA supplementations from 4,000 to 8,000 IU/kg improved lymphocytes, serum total antioxidant capacity (TAC), SOD, and IgM, while decreasing heterophils, heterophils/lymphocytes ratio, and creatinine in hatched chicks. Serum triglyceride concentration was reduced by adding 6,000 or 8,000 IU/kg of VA, while globulin and high-density lipoprotein concentrations were heightened only by 8,000 IU/kg of VA. It could be concluded that the dietary supplementation of VA (6,000 IU/kg) improved reproductive efficiency and antioxidative status in the liver and the shell gland of aged laying hens and improved hemato-biochemicals parameters, antioxidative status, and immunity of their offspring.

A metabolic perspective of the neutrophil life cycle: new avenues in immunometabolism

Neutrophils are the most abundant innate immune cells. Multiple mechanisms allow them to engage a wide range of metabolic pathways for biosynthesis and bioenergetics for mediating biological processes such as development in the bone marrow and antimicrobial activity such as ROS production and NET formation, inflammation and tissue repair. We first discuss recent work on neutrophil development and functions and the metabolic processes to regulate granulopoiesis, neutrophil migration and trafficking as well as effector functions. We then discuss metabolic syndromes with impaired neutrophil functions that are influenced by genetic and environmental factors of nutrient availability and usage. Here, we particularly focus on the role of specific macronutrients, such as glucose, fatty acids, and protein, as well as micronutrients such as vitamin B3, in regulating neutrophil biology and how this regulation impacts host health. A special section of this review primarily discusses that the ways nutrient deficiencies could impact neutrophil biology and increase infection susceptibility. We emphasize biochemical approaches to explore neutrophil metabolism in relation to development and functions. Lastly, we discuss opportunities and challenges to neutrophil-centered therapeutic approaches in immune-driven diseases and highlight unanswered questions to guide future discoveries.

Changes in Intake and Major Food Sources of Carotenoids among U.S. Adults between 2009-2018

Large epidemiologic studies suggest that diets rich in total or specific carotenoids are associated with a reduced risk of many chronic diseases. However, there are few studies characterizing trends in dietary carotenoid sources and intake among subgroups of the US adult population in the previous decade. This study aimed to assess these trends using data from 22,339 adults who participated in NHANES 2009-2018 cycles. Carotenoid intake and major food sources were calculated by linking food consumption data from the 24 h diet recall to an FNDDS 2009-2018 and the USDA's National Nutrient Database for Standard Reference (Release 28). Among US adults, mean (SE) dietary carotenoid intake was 9687.1 (158.0) mcg/day, and total intake was highest in men, non-smokers, moderate alcohol consumers, supplement users, and those with normal BMI, a PIR ≥ 1.85, and whose physical activity level was considered vigorous (p < 0.05). Carotenoid intake has gradually decreased over the past decade (p-trend: 0.097), especially among White adults (p-trend < 0.05), males (p-trend: 0.062), and those with a PIR of 1.0-1.3 (p-trend: 0.051), as have estimated rates of vitamin A adequacy. Tomatoes, carrots, and spinach were major food sources of carotenoids, and consumption of carrots and tomatoes decreased, while the consumption of lettuce, spinach, and salsa increased from 2009 to 2018. Our results warrant further studies investigating the consequences of the decreased tendencies of carotenoid intake on chronic disease risk, especially focusing on population subgroups exhibiting low or decreasing trends of carotenoid intake status.

Benefits and Harms of Edible Vegetable Oils and Fats Fortified with Vitamins A and D as a Public Health Intervention in the General Population: A Systematic Review of Interventions

This systematic review aims to assess whether edible vegetable oils and fats fortified with vitamin A and/or D are effective and safe in improving vitamin intake and ameliorating deficiency states in the general population. In November 2022, we systematically searched MEDLINE, Cochrane CENTRAL, Scopus, Global Index Medicus, ClinicalTrials.gov, and WHO ICTRP (International Clinical Trials Registry Platform) for randomized controlled trials (RCT) and non-randomized studies of interventions (NRSI) investigating the fortification of edible vegetable oils and fats with either vitamin A or vitamin D or both as compared to the same vegetable oils and/or fats without vitamin A and D fortification or no interventions, in the general population, without age restriction. We assessed the methodological quality of included RCTs using Cochrane's risk of bias tool 2.0 and of NRSIs using ROBINS-I tool. We performed random-effects meta-analysis and assessed certainty of evidence using GRADE. We included eight studies. Available evidence showed no significant effect of fortification with vitamin A on serum retinol levels (RCTs: MD 0.35 µmol/L, 95% CI -0.43 to 1.12; two trials; 514 participants; low-certainty evidence; CCTs: MD 0.31 µmol/L, 95% CI -0.18 to 0.80; two trials; 205 participants; very low-certainty evidence) and on subclinical vitamin A deficiency. Low-certainty evidence showed no effect of vitamin D fortification on serum 25-hydroxy vitamin D concentration (MD 6.59 nmol/L, 95% CI -6.89 to 20.07; one trial; 62 participants). In conclusion, vitamin A-fortified vegetable oils and fats may result in little to no difference in serum retinol levels in general populations. The dose of vitamin A used in the trials may be safe but may not be sufficient to reduce subclinical vitamin A deficiency. Further, the evidence suggests that vitamin D fortification results in little to no difference in serum 25-hydroxy vitamin D concentration. Several aspects of providing fortified oils and fats to the general population as a public health intervention should be further investigated, including optimal fortification dose, effects on vitamin D deficiency and its clinical symptoms and potential adverse effects.

Exploring the Effects of Vitamin D and Vitamin A Levels on the Response to COVID-19 Vaccine

COVID-19 vaccines were developed at an unprecedented speed in history. The factors affecting the response to COVID-19 vaccines are not clear. Herein, the effects of vitamin D and vitamin A (retinol) levels on the response to the BNT162b2 vaccine were explored. A total of 124 vaccine recipients were recruited from the general population attending vaccination centers in Irbid, Jordan. Blood samples were collected immediately before receiving the first vaccine dose (D0) and three weeks later (D21). Baseline (D0) levels of 25-hydroxyvitamin D [25(OH)D], retinol, and SARS-CoV-2 S1 IgG antibodies were measured with ELISA. The response to the BNT162b2 vaccine was tested by measuring the levels and avidity of SARS-CoV-2 S1 IgG antibodies on D21. The participants were divided into two groups, unexposed and exposed, based on the D0 SARS-CoV-2 antibody results. No significant correlation was found between the levels of 25(OH)D or retinol and the levels, avidity, or fold increase of antibodies in both groups. Similarly, no significant difference in antibody response was found between 25(OH)D status groups, retinol status groups, or combined status groups. These findings show that the baseline vitamin D or vitamin A levels have no effect on the short-term response to a single dose of BNT162b2 vaccine.

Vitamin A Promotes the Repair of Mice Skeletal Muscle Injury through RARα

Vitamin A (VitA) is an important fat-soluble vitamin which plays an important role in cell growth and individual development. However, the effect of VitA on the repair process of muscle injury and its molecular mechanism are still unclear. In this study, VitA and RA were first added to the culture medium of differentiated cells. We then detected cell differentiation marker proteins and myotube fusion. Moreover, the effects of VitA on RARα expression and nuclear translocation were further examined. The results showed that VitA significantly promoted the differentiation of C2C12, and the expression of RARα was significantly increased. Furthermore, VitA was injected into skeletal muscle injury in mice. HE staining and Western Blot results showed that VitA could significantly accelerate the repair of skeletal muscle injury and VitA increase the expression of RARα in mice. This study provides a theoretical basis for elucidating the regulation mechanism of VitA-mediated muscle development and the development of therapeutic drugs for muscle diseases in animals.

Controlling viral inflammatory lesions by rebalancing immune response patterns

In this review, we discuss a variety of immune modulating approaches that could be used to counteract tissue-damaging viral immunoinflammatory lesions which typify many chronic viral infections. We make the point that in several viral infections the lesions can be largely the result of one or more aspects of the host response mediating the cell and tissue damage rather than the virus itself being directly responsible. However, within the reactive inflammatory lesions along with the pro-inflammatory participants there are also other aspects of the host response that may be acting to constrain the activity of the damaging components and are contributing to resolution. This scenario should provide the prospect of rebalancing the contributions of different host responses and hence diminish or even fully control the virus-induced lesions. We identify several aspects of the host reactions that influence the pattern of immune responsiveness and describe approaches that have been used successfully, mainly in model systems, to modulate the activity of damaging participants and which has led to lesion control. We emphasize examples where such therapies are, or could be, translated for practical use in the clinic to control inflammatory lesions caused by viral infections.

Graft-versus-host disease: teaching old drugs new tricks at less cost

Graft-versus-host disease (GVHD) remains a major cause of morbidity and mortality after allogeneic stem cell transplantation (SCT). Currently, more patients can receive SCT. This is attributed to the use of reduced intensity regimens and the use of different GVHD prophylaxis that breaks the barrier of human leukocyte antigen, allowing an increase in the donor pool. Once an area with relatively few clinical trial options, there has been an increase in interest in GVHD prophylaxis and treatment, which has led to many US Food and Drug Administration (FDA) approvals. Although there is considerable excitement over novel therapies, many patients may not have access to them due to geographical or other resource constraints. In this review article, we summarize the latest evidence on how we can continue to repurpose drugs for GVHD prophylaxis and treatment. Drugs covered by our review include those that have been FDA approved for other uses for at least 15 years (since 2008); thus, they are likely to have generic equivalents available now or in the near future.

Fatty acid- and retinol-binding protein 6 does not control worm fatty acid content in Caenorhabditis elegans but might play a role in Haemonchus contortus parasitism

BACKGROUND

Nematodes have lost the ability to synthesise necessary lipids de novo and have complementally evolved the capacity to acquire fatty acids and their derivatives from a diet or host animal. Nematode-specific fatty acid- and retinol-binding protein (FAR) family is one approach that facilitates lipid acquisition, representing an Achilles heel and potential target against roundworms of socioeconomic significance. However, little is known about their detailed functional roles in either free-living or parasitic nematodes.

METHODS

A genome-wide identification and curation were performed to screen the FAR family members of Haemonchus contortus. Their transcription patterns in worms were also analysed to identify the targets. Ligand binding assay and molecular docking were conducted to verify the fatty acid binding activities of FAR proteins of interest. RNA interference (RNAi) and heterologous expression (rescuing) experiments were designed to explore the potential roles of the selected FAR protein in nematodes. Localisation of the protein was shown in sections of paraffin-embedded worms after an immunohistochemistry (IHC) assay.

RESULTS

Here, an orthologue of far-6 in the model organism Caenorhabditis elegans (Ce-far-6) was functionally characterised in a parasitic nematode, H. contortus (Hc-far-6). It is demonstrated that knockdown of Ce-far-6 gene did not affect worm fat content, reproduction, or lifespan, but decreased worm body length at an early life stage of C. elegans. In particular, the Ce-far-6 mutant associated phenotype was completely rescued by Hc-far-6, suggesting a conserved functional role. Surprisingly, there were distinct tissue expression patterns of FAR-6 in the free-living C. elegans and parasitic H. contortus. High transcriptional level of Hc-far-6 and dominant expression of FAR-6 in the intestine of the parasitic stage of H. contortus link this gene/protein to nematode parasitism.

CONCLUSIONS

These findings substantially enhance our understanding of far genes and the associated lipid biology of this important parasitic nematode at a molecular level, and the approaches established are readily applicable to the studies of far genes in a broad range of parasites.

Preventing bacterial disease in poultry in the post-antibiotic era: a case for innate immunity modulation as an alternative to antibiotic use

The widespread use of antibiotics in the poultry industry has led to the emergence of antibiotic-resistant bacteria, which pose a significant health risk to humans and animals. These public health concerns, which have led to legislation limiting antibiotic use in animals, drive the need to find alternative strategies for controlling and treating bacterial infections. Modulation of the avian innate immune system using immunostimulatory compounds provides a promising solution to enhance poultry immune responses to a broad range of bacterial infections without the risk of generating antibiotic resistance. An array of immunomodulatory compounds have been investigated for their impact on poultry performance and immune responses. However, further research is required to identify compounds capable of controlling bacterial infections without detrimentally affecting bird performance. It is also crucial to determine the safety and effectiveness of these compounds in conjunction with poultry vaccines. This review provides an overview of the various immune modulators known to enhance innate immunity against avian bacterial pathogens in chickens, and describes the mechanisms involved.

Bacteria from the gut influence the host micronutrient status

Micronutrient deficiencies or "hidden hunger" remains a serious public health problem in most low- and middle-income countries, with severe consequences for child development. Traditional methods of treatment and prevention, such as supplementation and fortification, have not always proven to be effective and may have undesirable side-effects (i.e., digestive troubles with iron supplementation). Commensal bacteria in the gut may increase bioavailability of specific micronutrients (i.e., minerals), notably by removing anti-nutritional compounds, such as phytates and polyphenols, or by the synthesis of vitamins. Together with the gastrointestinal mucosa, gut microbiota is also the first line of protection against pathogens. It contributes to the reinforcement of the integrity of the intestinal epithelium and to a better absorption of micronutrients. However, its role in micronutrient malnutrition is still poorly understood. Moreover, the bacterial metabolism is also dependent of micronutrients acquired from the gut environment and resident bacteria may compete or collaborate to maintain micronutrient homeostasis. Gut microbiota composition can therefore be modulated by micronutrient availability. This review brings together current knowledge on this two-way relationship between micronutrients and gut microbiota bacteria, with a focus on iron, zinc, vitamin A and folate (vitamin B9), as these deficiencies are public health concerns in a global context.

Vitamin A Promotes the Fusion of Autophagolysosomes and Prevents Excessive Inflammasome Activation in Dextran Sulfate Sodium-Induced Colitis

Vitamin A ensures intestinal homeostasis, impacting acquired immunity and epithelial barrier function; however, its role in innate immunity is mostly unknown. Here, we studied the impact of vitamin A in different dextran sulfate sodium (DSS)-induced colitis animal models. Interestingly, more severe DSS-induced colitis was observed in vitamin A-deficient (VAD) mice than in vitamin A-sufficient (VAS) mice; the same was observed in VAD severe combined immunodeficient mice lacking T/B cells. Remarkably, IL-1β production, LC3B-II expression, and inflammasome activity in the lamina propria were significantly elevated in VAD mice. Electron microscopy revealed numerous swollen mitochondria with severely disrupted cristae. In vitro, non-canonical inflammasome signaling-induced pyroptosis, LC3B-II and p62 expression, and mitochondrial superoxide levels were increased in murine macrophages (RAW 264.7) pretreated with retinoic acid receptor antagonist (Ro41-5253). These findings suggest that vitamin A plays a crucial role in the efficient fusion of autophagosomes with lysosomes in colitis.

Nutrition in children with exocrine pancreatic insufficiency

Exocrine pancreatic insufficiency (EPI) is a condition defined as pancreatic loss of exocrine function, including decreased digestive enzymes and bicarbonate secretion, which leads to maldigestion and malabsorption of nutrients. It is a common complication in many pancreatic disorders. If left undiagnosed, EPI can cause poor digestion of food, chronic diarrhea, severe malnutrition and related complications. Nutritional status and fat-soluble vitamins should be carefully assessed and monitored in patients with EPI. Early diagnosis of EPI is clinically important for appropriate nutritional support and initiating pancreatic enzyme replacement therapy (PERT) which could significantly improve patient outcomes. The evaluation of nutritional status and related unique management in children with EPI will be discussed in this review.

Effect of oral vitamin A supplementation on host immune response to infectious bronchitis virus infection in specific pathogen-free chicken

Vitamin A is a fat-soluble vitamin that is a crucial mediator of the immune system. In this study, we evaluated the effect of oral vitamin A supplementation on host immune responses to infectious bronchitis virus (IBV) infection in chickens. Forty 1-day-old specific pathogen-free (SPF) chickens were fed a basal diet and randomly divided into 2 groups (n = 20 birds per group). Chickens in the experimental group were treated orally with vitamin A (dissolved in 0.1 mL soybean oil, at a dose of 8,000 IU per kg diet) daily. Birds in the control group were orally administered 0.1 mL soybean oil without vitamin A until 21 d of age. On d 21 after birth, all chickens were infected with 0.1 mL of 10^6.5 50% median embryo infectious dose of a pathogenic IBV strain (CK/CH/LDL/091022) by intraocular and intranasal routes. The results demonstrated that oral vitamin A supplementation did not affect the clinical course of disease and growth performance of SPF chickens. However, vitamin A supplementation increased the IBV-specific IgG serum levels and decreased the viral load in some tissues of IBV-infected chickens. In addition, the results demonstrated that vitamin A supplementation decreased the expression levels of most immune-related molecules in some tissues of IBV-infected chickens. Vitamin A supplementation decreased the mRNA expression levels of some avian β-defensins (AvBD2, 3, 6, 7, 11, and 13) and increased the expression levels of AvBD9 and AvBD12 in some tissues of IBV-infected chickens. Similarly, vitamin A supplementation decreased the mRNA expression levels of some cytokines (interferon-γ, interleukin-1β [IL-1β], and IL-6) and increased the mRNA expression levels of IL-2 in some tissues of IBV-infected chickens. Furthermore, vitamin A supplementation decreased the mRNA expression levels of myeloid differentiation primary response protein 88, nuclear factor-κB p65, toll-like receptor 3, toll-like receptor 7, and CD4. In summary, the present study suggests that vitamin A supplementation enhances the immune function of SPF chickens against IBV infection by inhibiting viral replication, increasing the IBV-specific antibody titer, and suppressing the excessive inflammatory responses to IBV infection.

Antioxidant Characterization of Six Tomato Cultivars and Derived Products Destined for Human Consumption

The consumption of fresh tomatoes and processed tomato products is widespread in the Mediterranean diet. This fruit is a valuable source of antioxidants and plays an important role in preventing oxidative stress. This study aimed to investigate the content of antioxidants and measure the total antioxidant capacity (ABTS and DPPH assays) in the peel, pulp, and seed fractions of six tomato cultivars. Finally, some bioactive compounds and total antioxidant activity were also determined in homemade tomato purees, since such homemade production is commonplace in Southern Italy. The level of antioxidants and total antioxidant capacity in each fraction were also calculated based on their actual fresh weight in the whole tomato. The overall results indicated that the peel and seeds of all analysed tomato cultivars contribute significantly to the antioxidant charge of the fruits. Consequently, consuming tomatoes without peel and seeds results in a substantial loss of compounds beneficial for human health. Our results also showed that phenolic and lycopene content, as well as antioxidant activities in all purees are higher than in fresh tomatoes. Based on this evidence, producing homemade tomato puree is a good practice, and its consumption helps prevent oxidative stress damage.

Retinoic acid receptor activity is required for the maintenance of type 1 innate lymphoid cells

Group 1 innate lymphoid cells (G1-ILCs) are innate immune effectors critical for the response to intracellular pathogens and tumors. G1-ILCs comprise circulating natural killer (NK) cells and tissue-resident type 1 ILCs (ILC1s). ILC1s mainly reside in barrier tissues and provide the initial sources of interferon-γ (IFN-γ) to prime the protecting responses against infections, which are followed by the response of recruited NK cells. Despite such distribution differences, whether local environmental factors influence the behavior of NK cells and ILC1s is unclear. Here, we show that the signaling of retinoic acid (RA), active metabolites of vitamin A, is essential for the maintenance of ILC1s in the periphery. Mice expressing RARα403, a truncated form of retinoic acid receptor α (RARα) that exerts dominant negative activity, in a lymphoid cell- or G1-ILC-specific manner showed remarkable reductions of peripheral ILC1s while NK cells were unaffected. Lymphoid cell-specific inhibition of RAR activity resulted in the reduction of PD-1+ ILC progenitors (ILCPs), but not of common lymphoid progenitors (CLPs), suggesting the impaired commitment and differentiation of ILC1s. Transcriptome analysis revealed that RARα403-expressing ILC1s exhibited impaired proliferative states and declined expression of effector molecules. Thus, our findings demonstrate that cell-intrinsic RA signaling is required for the homeostasis and the functionality of ILC1s, which may present RA as critical environmental cue targeting local type 1 immunity against infection and cancer.

Investigation of Vitamin a and 25(OH)D3 Levels in Cattle with Pneumonia Detected Mycoplasma bovis

This study investigated the presence of Mycoplasma bovis in nasal swabs taken from cattle with pneumonia, to reveal the clinical and biochemical findings of positive animals, and determine the levels of vitamin A and 25(OH)D3. In the study were included 103 infected cattle and 10 healthy cattle, all aged 1-4 years, as the control group. Quantitative clinical evaluations and clinical examinations were performed on each animal, and 5 ml blood samples and nasal swabs were taken. Serum biochemistry, vitamin A and 25(OH)D3 levels were determined in both positive and control samples. The clinical signs were identified by qualitative scoring in M. bovis positive animals. Regarding the clinical findings, respiratory frequency, heart rate, and rectal temperature were significantly higher in positive than control group animals (p<0.001). Regarding the biochemistry findings, albumin (ALB) and glucose (GLU) levels were lower in cattle infected with M. bovis (p<0.001) whereas total protein (TP) and alkaline phosphatase (ALP) levels were higher (p<0.001). While serum 25(OH)D3 levels were lower in infected animals (p<0.001), there was no significant difference (p>0.05) in serum vitamin A levels. In this study, clinical findings in cattle naturally infected with M. bovis were expressed qualitatively and quantitatively. In addition, it has been revealed that the disease does not only cause lung involvement, but also causes changes in biochemical and vitamin levels. Although these parameters cannot be used as a biomarker in the diagnosis of pneumonia, they are thought to provide benefits in terms of diagnosis, treatment and prophylaxis in practice.

Retinoids stored locally in the lung are required to attenuate the severity of acute lung injury in male mice

Retinoids are potent transcriptional regulators that act in regulating cell proliferation, differentiation, and other cellular processes. We carried out studies in male mice to establish the importance of local cellular retinoid stores within the lung alveolus for maintaining its health in the face of an acute inflammatory challenge induced by intranasal instillation of lipopolysaccharide. We also undertook single cell RNA sequencing and bioinformatic analyses to identify roles for different alveolar cell populations involved in mediating these retinoid-dependent responses. Here we show that local retinoid stores and uncompromised metabolism and signaling within the lung are required to lessen the severity of an acute inflammatory challenge. Unexpectedly, our data also establish that alveolar cells other than lipofibroblasts, specifically microvascular endothelial and alveolar epithelial cells, are able to take up lipoprotein-transported retinoid and to accumulate cellular retinoid stores that are directly used to respond to an acute inflammatory challenge.

Nutrients in prevention, treatment, and management of viral infections; special focus on Coronavirus

BACKGROUND

The coronavirus disease 2019 (COVID-19) is a pandemic caused by coronavirus with mild to severe respiratory symptoms. This paper aimed to investigate the effect of nutrients on the immune system and their possible roles in the prevention, treatment, and management of COVID-19 in adults.

METHODS

This Systematic review was designed based on the guideline of the Preferred Reporting for Systematic Reviews (PRISMA). The articles that focussed on nutrition, immune system, viral infection, and coronaviruses were collected by searching databases for both published papers and accepted manuscripts from 1990 to 2020. Irrelevant papers and articles without English abstract were excluded from the review process.

RESULTS

Some nutrients are actively involved in the proper functioning and strengthening of the human immune system against viral infections including dietary protein, omega-3 fatty acids, vitamin A, vitamin D, vitamin E, vitamin B₁, vitamin B₆, vitamin B₁₂, vitamin C, iron, zinc, and selenium. Few studies were done on the effect of dietary components on prevention of COVID-19, but supplementation with these nutrients may be effective in improving the health status of patients with viral infections.

CONCLUSION

Following a balanced diet and supplementation with proper nutrients may play a vital role in prevention, treatment, and management of COVID-19. However, further clinical trials are needed to confirm these findings and presenting the strong recommendations against this pandemic.

Weaning diet supplemented with health-promoting feed additives influences microbiota and immune response in piglets challenged with Salmonella

The aim of this study was to evaluate the potential of micronutrients and feed additives to modulate intestinal microbiota and systemic and mucosal immune responses in weaned pigs infected with Salmonella. At weaning, 32 litters of 12 piglets each were allocated to four dietary treatments: 1) control diet (CTRL), 2) CTRL supplemented with chlortetracycline (ATB), 3) CTRL supplemented with a cocktail of feed additives (CKTL); and 4) CKTL diet containing bovine colostrum in replacement of spray-dry animal plasma (CKTL+COL). The CKTL supplement included cranberry extract, encapsulated carvacrol and yeast-derived products and an enriched selenium and vitamin premix. Three weeks after weaning, four pigs per litter were orally inoculated with Salmonella Typhimurium DT104. Half of them were euthanized 3 days post-infection (dpi) and the other half, 7 dpi. The expression of IL6, TNF, IL8, monocyte chemoattractant protein 1 (MCP1), IFNG, cyclooxygenase 2 (COX2), glutathione peroxidase 2 (GPX2) and β-defensin 2 (DEFB2) showed a peaked response at 3 dpi (P < 0.05). Results also revealed that DEFB2 expression was higher at 3 dpi in CTRL and CKTL groups than in ATB (P = 0.01 and 0.06, respectively) while GPX2 gene was markedly increased at 3 and 7 dpi in pigs fed CKTL or CKTL+COL diet compared to CTRL pigs (P < 0.05). In piglets fed CKTL or CKTL+COL diet, intestinal changes in microbial communities were less pronounced after exposure to Salmonella compared to CTRL and progressed faster toward the status before Salmonella challenge (AMOVA P < 0.01). Furthermore, the relative abundance of several families was either up- or down-regulated in pigs fed CKTL or CKTL+COL diet after Salmonella challenge. In conclusion, weaning diet enriched with bovine colostrum, vitamins and mixture of feed additives mitigated the influence of Salmonella infection on intestinal microbial populations and modulate systemic and intestinal immune defences.

Vitamin A Deficiency, COVID-19, and Rhino-Orbital Mucormycosis (Black Fungus): An Analytical Perspective

Mucormycosis is a rare but serious opportunistic fungal disease characterized by rhino-orbito-cerebral and pulmonary involvement. It is mainly seen in people with secondary immunosuppression, isolated vitamin A deficiency, measles, and AIDS patients. It showed a rise during the second wave of the COVID-19 epidemic in the spring of 2021 in India, especially in diabetic COVID-19 patients. Vitamin A deficiency is known to cause nutritional immunodeficiency and hence leading the way to increased opportunistic fungal, bacterial, and viral infections. In the eye, it causes keratitis, night blindness, xerophthalmia, conjunctivitis, Bitot spots, keratomalacia, and retinopathy. It also causes decreased tear secretion and deterioration of the anatomical/physiological defense barrier of the eye. The negative impact of vitamin A deficiency has been previously demonstrated in measles, AIDS, and COVID-19. We think that mucormycosis in COVID-19 might be rendered by vitamin A deficiency and that vitamin A supplementation may have preventive and therapeutic values against mucormycosis and other ocular symptoms associated with COVID-19. However, any vitamin A treatment regimen needs to be based on laboratory and clinical data and supervised by medical professionals.

The protective effect of vitamin A on Concor induced structural changes of the liver and kidney in adult rats

Concor is a beta-blocker drug used to treat high blood pressure, acute coronary syndrome, and to control the rapid pulse of the heart such as atrial fibrillation. Some of its adverse effects include hepatitis, increased triglycerides and liver enzymes. Monitoring liver and kidney functions in patients with hepatic or renal impairment who are taking concor is recommended.

The current study was undertaken to define whether vitamin A could improve structural changes in the liver and kidneys. The 24 rats were grouped into the following. The first group was control. The second group was given Vitamin A (5000 IU). Group 3: given concor at a daily dose of 0.9 mg/kg B. wt. Group IV: received concor (0.9 mg/kg B. wt.) and Vitamin A (5000 IU) orally. After 4 weeks, the kidney of the treated group 3 exhibited degenerative alterations in the glomeruli, enlargement of Bowman’s space and the epithelium of the proximal kidney tubules showed vacuolar degeneration with necrosis. Liver sections showed degeneration and necrosis of hepatocytes, congestion of the central vein, dilation of sinusoids and inflammatory cell infiltration. Group 4 showed mild degeneration in the glomeruli, expansion of Bowman’s space and mild degeneration of tubular epithelium, and normal architecture of the liver with increased Kupffer cells. From this study, we concluded that concor drug induces structural changes in the liver and kidney and these effects were improved by Vitamin A administration.

Frequency of Vitamin a Deficiency in Children Hospitalized for Pneumonia: An Integrative Review

Objective: To identify the frequency of vitamin A deficiency in children aged 6 months to 5 years hospitalized for pneumonia. Methods: An integrative literature review was carried out, where searches were made by two independent researchers, with no language limits or publication time in the databases PubMed, LILACS, Web of Science, Scopus and CINAHL, and in the gray literature-OpenGrey, Proquest and Google Scholar. In the eligibility phase, the screened studies were read in full and those that did not answer the research question were excluded. Methodological quality was assessed using the Downs & Black (1998) checklist. Results: 1642 articles were identified, after all stages of screening and selection, 10 studies were included, of which 5 were longitudinal, 4 were intervention and 1 transversal. All studies identified subclinical vitamin A deficiency in children hospitalized with pneumonia; the highest frequency of subclinical vitamin A deficiency was 93.2%. All studies evaluated showed frequencies of subclinical vitamin A deficiency >20%. Conclusion: There is a high frequency of subclinical vitamin A deficiency in children with pneumonia; these data need to be further explored in terms of their associations. For this reason, new studies that evaluate this topic are of fundamental importance.

Influence of Vitamin A supplementation on inflammatory biomarkers in adults: a systematic review and meta-analysis of randomized clinical trials

Vitamin A is an anti-oxidant which has been presumed to act as an anti-infective vitamin in many studies. This study aimed to evaluate the association between vitamin A supplementation and c-reactive protein (CRP), tumor necrosis factor-alpha (TNF-α), and interleukin 6 (IL-6) levels in randomized control trials (RCTs) studies on adults. A systematic search was performed on databases including PUBMED, SCOPUS, and the Cochrane library. The studies included were considered for data extraction and subsequently assessed for effect. Weighted mean differences (WMD) and 95% confidence intervals (CIs) were evaluated. Among 13,219 articles 13 studies were included for analysis of CRP and TNF-α, as well as 9 studies included for IL-6 in quality and quantity. The pooled WMD analysis of CRP demonstrated that vitamin A supplementation significantly increased CRP concentration with (WMD: 0.84 mg/L; 95% CI 0.29-1.39, I² = 0.96.2% and p value < 0.003). However, there was no significant correlation between vitamin A supplementation and lower plasma TNF-α (p < 0.45)). Subgroup analysis by dosage demonstrate significant association between vitamin A supplementation and IL-6 in dosage with 50,000 with (WMD: - 1.53 mg/L; 95% CI - 2.36 to - 0.71, p value < 0.00001) as well as a negative significant association was seen at 44 weeks of supplementation with 50,000 IU/day retinyl palmitate and TNF-a in chronic hepatitis B conditions with (- 0.94 (- 1.19, - 0.69) p < 0.0001). The result of this study demonstrates that supplementation of vitamin A at low and high dosages for short and long durations increases the CRP plasma concentrations on adults and vitamin A supplementation decreases the TNF-α concentrations in chronic hepatitis B on adults. Therefore, there is an inverse association between vitamin A supplementation and plasma and fecal IL-6 concentrations in many infection conditions.

Region-specific COVID-19 risk scores and nutritional status of a high-risk population based on individual vulnerability assessment in the national survey data

BACKGROUND & AIMS

Coronavirus disease 2019 (COVID-19) is an ongoing pandemic outbreak leading to more than 1 million deaths worldwide as reported in 2020. Several risk assessment tools, including individual vulnerability to COVID-19, have been developed. The present study aimed to characterize a high-risk population using such a tool and examine risk factors and nutritional status in the national survey data and estimate the region-specific population size.

METHODS

The study included 17,540 Korean adults who participated in the Korea National Health and Nutrition Examination Survey (KNHANES). The risk scores for individual vulnerability to COVID-19 were calculated based on age, sex, smoking status, and comorbidities, and a high-risk population was defined as having risk scores ≥11. Nutritional status was compared between the high-risk population and the remaining participants in the KNHANES data. The region-specific population size was estimated using national statistics.

RESULTS

The proportion of the high-risk population was estimated to be 10.5%, which corresponds to approximately 4.6 million adults in South Korea. About 20% of them had inadequate intake of all of vitamins A, B1, B2, B3, and C below the estimated average requirement. The high-risk population showed 1.65 [95% confidence interval: 1.39, 1.96] higher odds of inadequate intake of multiple vitamins than the remaining participants. In the ecological analysis, the region-specific numbers of the high-risk population correlated significantly with the actual numbers of deaths due to COVID-19 (P value = 0.013).

CONCLUSIONS

These results suggest that individuals vulnerable to COVID-19, in particular those are living in densely populated regions, should pay particular attention to the protection against this pandemic and have adequate nutritional status, which may support optimal immune function.

Association between Circulating Retinol Binding Protein 4, Body Mass Index, and Biomarkers of Environmental Enteric Dysfunction among Slum-Dwelling Lean Adults in Bangladesh

The relationship of retinol binding protein 4 (RBP4) with biomarkers of intestinal health and gut integrity in adults is unknown. We sought to determine the correlation between plasma RBP4 level and BMI and investigate the relationship of circulating RBP4 concentration with biomarkers of environmental enteric dysfunction among lean adults (body mass index [BMI] < 25.0 kg/m2) in Bangladesh. Overall, 270 adults (135 undernourished with a BMI < 18.5 kg/m2 and 135 healthy controls with a BMI between 18.5 and 24.9 kg/m2) aged 18 to 45 years were evaluated. Multivariable linear regression was performed to test the association between RBP4 and fecal biomarkers of impaired gut health. RBP4 concentration was positively correlated (rho = 0.27, P < 0.001) with BMI and was significantly higher in healthy controls than undernourished adults (P < 0.001), in male than female (P < 0.001), and also in employed (P < 0.001), smokers (P = 0.048) and participants with low Self-Reporting Questionnaire (SRQ)-20 scores (an instrument to screen mental health disorders) (P = 0.049). Statistically significant negative correlations were observed between RBP4 and fecal biomarkers of gut enteropathy including myeloperoxidase (rho = -0.23, P < 0.001), neopterin (rho = -0.30, P < 0.001), and alpha-1 anti-trypsin (rho = -0.21, P < 0.001). Multivariable linear regression analysis showed that increased RBP4 concentration was associated with a significant reduction in fecal neopterin (coefficient = -0.95; 95% confidence interval: -1.44 to -0.45]; P < 0.001) after adjustment for age, sex, nutritional status at enrollment, education, dietary diversity score, SRQ-20 score, improved sanitation, household animal exposure, and alpha-1-acid glycoprotein. The study findings revealed an inverse relationship of plasma RBP4 concentration with fecal biomarkers of altered gut health among slum-dwelling lean adults in Bangladesh.

Vitamin A Nutritional Status Is a Key Determinant of Bone Mass in Children

The bone mass increases that occur during the period of childhood are of great significance for maximizing the peak bone mass in adults and preventing for osteoporosis. Studies have reported that VA can improve the bone health in adults. Moreover, limited studies have assessed such associations in children. In this cross-sectional study including 426 children, we assessed the children’s plasma retinol concentration by liquid chromatography–mass spectrometry and the dietary intake of VA and carotenoids using a structured Food Frequency Questionnaire. Their bone mineral content and bone mineral density (BMD) were measured using dual-energy X-ray absorptiometry. After adjusting for potential confounders, the restricted cubic spline revealed an inverted U-shaped association between plasma retinol concentration and BMD; the estimated effects on the TBLH BMD per μmol/L increase in the plasma retinol concentration were 1.79 × 10⁻² g/cm² below 1.24 μmol/L and −5.78 × 10⁻³ g/cm² above this point (p for non-linearity = 0.046). A multiple linear regression analysis revealed a positive association between the plasma retinol concentration and the TBLH BMC (β = 1.89, 95% CI: 1.64 × 10⁻¹–3.62, p = 0.032). In conclusion, an appropriate plasma retinol concentration and greater intakes of dietary VA and β-carotene may enhance the bone mineral status of children who are aged 6–9 years.

Vitamin A in children's pneumonia for a COVID-19 perspective: A systematic review and meta-analysis of 15 trials

BACKGROUND

To systematically review and meta-analyze the efficacy of vitamin A as an adjuvant therapy for pneumonia in children.

METHODS

We searched in PubMed, the Cochrane Library, Chinese National Knowledge Infrastructure, WanFang Database and Chongqing VIP information network from libraries building to March 2022, screening randomized controlled trials (RCT) about vitamin A combined with conventional therapy for pneumonia in children. Two researchers used the Cochrane risk of bias tool to assess the quality of included studies dependently. Data analysis was conducted in the RevMan 5.3.

RESULTS

15 trials involving 3496 patients (treated group: 1898; control group: 1598) were analyzed in this study. The Meta-analysis showed that vitamin A combined with conventional therapy improved clinical efficacy (P < .05), shortened the duration of fever and cough, negative time of chest X-ray, and the hospitalization, lung rale disappearance, choking milk disappearance, shortness of breath disappearance and perilabial cyanosis disappearance (P < .05). However, vitamin A combined with conventional therapy did not reduce the mortality of pneumonia in children (P > .05).

CONCLUSION

Vitamin A contributes to relieve the clinical symptoms and signs, and also shorten the hospitalization.

Modulation of immunological responses by aqueous extract of Datura stramonium L. seeds on cyclophosphamide-induced immunosuppression in Wistar rats

Background

Datura stramonium L. (Solanaceae) is used traditionally in west Africa to treat asthma, epilepsy, rheumatoid arthritis, filariasis microbial infections and conjunctivitis. This study investigated the immunomodulatory effects of aqueous seed extract of D. stramonium L. (ASEDS) on Wistar rats.

Methods

Thirty Wistar albino rats (180–200 g) were randomized into 6 groups (n = 5). Group 1 received distilled water only. Rats in groups 2–6 were pretreated with 10 mg/kg body weight (b.w.) Cyclophosphamide orally for 27-days to induce immunosuppression. Thereafter, they received treatment orally for 28 days as follows: Group 2 (distilled water), group 3 (5 mg/kg b.w. Levamisole), groups 4–6 (60, 90 and 120 mg/kg b.w. ASEDS, respectively). HPLC was used to determine major compounds in ASEDS. The effects of ASEDS on immune cells, immunoglobulins A, G and M levels, lipoproteins, and antioxidant status of rats were evaluated.

Results

ASEDS indicated high content of Acutumine, Quinine, Catechin, Chlorogenic acid, Gallic acid, Quercetin, Vanillic acid, Luteolin, Formosanin C, Saponin, Cyanidin, Tannic acid, 3-Carene, Limonene and α-terpineol. Cyclophosphamide triggered significant (p < 0.05) reduction in total leucocyte count and differentials, IgA, IgG, high-density lipoproteins (HDL), catalase, superoxide dismutase, glutathione peroxidase, vitamins A, C and E levels of untreated rats. Administration of ASEDS led to significant (p < 0.05) improvement in immune cell counts, immunoglobulin synthesis, high-density lipoprotein concentration, and antioxidant status of rats in the treated groups.

Conclusions

The results obtained from the study showed the immunomodulatory activity of ASEDS, thereby indicating its potential in immunostimulatory drug discovery.

An overview of the genetic aspects of hair loss and its connection with nutrition

Hair loss is a widespread concern in dermatology clinics, affecting both men's and women's quality of life. Hair loss can have many different causes, which are critical to identify in order to provide appropriate treatment. Hair loss can happen due to many variables, such as genetic factors or predisposition, vitamin and mineral deficiencies, skin problems, hair growth disorders, poor diet, hormonal problems, certain internal diseases, drug use, stress and depression, cosmetic factors, childbirth, and the chemotherapy process. Treatment for hair loss varies depending on the type of alopecia, deficiency, or excess of structures such as vitamins and minerals, and also on hair and skin structure. The Mediterranean diet is characterized by low amounts of saturated fat, animal protein, and high amounts of unsaturated fat, fiber, polyphenols, and antioxidants. The main nutrients found in the Mediterranean Diet are rich in antioxidant, anti-inflammatory components. It also has an important place in hair loss treatment, since recently treatment strategies have included polyphenols and unsaturated oils more and more frequently. The goal of this work was to review published articles examining alopecia and its types, the many micronutrients that affect alopecia, and the role of the Mediterranean diet in alopecia. The literature shows that little is known about hair loss, nutritional factors, and diet, and that the data collected are conflicting. Given these differences, research into the function of diet and nutrition in the treatment of baldness is a dynamic and growing topic.

Effect of vitamin A supplementation on the outcome severity of COVID-19 in hospitalized patients: A pilot randomized clinical trial

INTRODUCTION

Vitamin A is one of the vitamins that is suggested as adjuvant therapy in viral infections due to its immune enhancing role. In the present clinical trial, we intended to assess the effect of vitamin A supplementation on Coronavirus disease-2019 (COVID-19) in hospitalized patients.

METHODS

The present pilot randomized controlled clinical trial was conducted on 30 hospitalized patients with COVID-19. Patients in the intervention group received 50000 IU/day intramuscular vitamin A for a maximum of two weeks. Patients in the control group continued their common treatment protocols. All participants were followed up until discharge from the hospital or death. The primary outcome of the study was time to achieve clinical response based on the six classes of an ordinal scale. Time to clinical response was calculated based on the days needed to improve two scores on the scale or patient's discharge.

RESULTS

The time to clinical response was not significantly different between the two groups (7.23 ± 2.14 vs. 6.75 ± 1.85 days, respectively, p = 0.48). There was no significant difference between the groups regarding clinical response (hazard ratio: 1.76 [95% CI: 0.73, 4.26]). There were no significant differences between groups regarding the need for mechanical ventilation, duration of hospitalization, or death in the hospital.

CONCLUSION

The results of this pilot clinical trial showed no benefit of vitamin A compared with the common treatment on outcome severity in hospitalized patients with COVID-19. Although the results are negative, there is still a great need for future clinical studies to provide a higher level of evidence.

Porcine bile acids promote the utilization of fat and vitamin A under low-fat diets

Fat-soluble vitamin malabsorption may occur due to low dietary fat content, even in the presence of an adequate supply of fat-soluble vitamins. Bile acids (BAs) have been confirmed as emulsifiers to promote fat absorption in high-fat diets. However, there are no direct evidence of exogenous BAs promoting the utilization of fat-soluble vitamins associated with fat absorption in vitro and in vivo. Therefore, we chose laying hens as model animals, as their diet usually does not contain much fat, to expand the study of BAs. BAs were investigated in vitro for emulsification, simulated intestinal digestion, and release rate of fat-soluble vitamins. Subsequently, a total of 450 healthy 45-week-old Hy-Line Gray laying hens were chosen for an 84-day feeding trial. They were divided into five treatments, feeding diets supplemented with 0, 30, 60, 90, and 120 mg/kg BAs, respectively. No extra fat was added to the basic diet (crude fat was 3.23%). In vitro, BAs effectively emulsified the water-oil interface. Moreover, BAs promoted the hydrolysis of fat by lipase to release more fatty acids. Although BAs increased the release rates of vitamins A, D, and E from vegetable oils, BAs improved for the digestion of vitamin A more effectively. Dietary supplementation of 60 mg/kg BAs in laying hens markedly improved the laying performance. The total number of follicles in ovaries increased in 30 and 60 mg/kg BAs groups. Both the crude fat and total energy utilization rates of BAs groups were improved. Lipase and lipoprotein lipase activities were enhanced in the small intestine in 60, 90, and 120 mg/kg BAs groups. Furthermore, we observed an increase in vitamin A content in the liver and serum of laying hens in the 60, 90, and 120 mg/kg BAs groups. The serum IgA content in the 90 and 120 mg/kg BAs groups was significantly improved. A decrease in serum malondialdehyde levels and an increase in glutathione peroxidase activity were also observed in BAs groups. The present study concluded that BAs promoted the absorption of vitamin A by promoting the absorption of fat even under low-fat diets, thereupon improving the reproduction and health of model animals.

Functional constituents of plant-based foods boost immunity against acute and chronic disorders

Plant-based foods are becoming an increasingly frequent topic of discussion, both scientific and social, due to the dissemination of information and exchange of experiences in the media. Plant-based diets are considered beneficial for human health due to the supply of many valuable nutrients, including health-promoting compounds. Replacing meat-based foods with plant-based products will provide many valuable compounds, including antioxidants, phenolic compounds, fibers, vitamins, minerals, and some ω3 fatty acids. Due to their high nutritional and functional composition, plant-based foods are beneficial in acute and chronic diseases. This article attempts to review the literature to present the most important data on nutrients of plant-based foods that can then help in the prevention of many diseases, such as different infections, such as coronavirus disease, pneumonia, common cold and flu, asthma, and bacterial diseases, such as bronchitis. A properly structured plant-based diet not only provides the necessary nutrients but also can help in the prevention of many diseases.

Serum Vitamins A, D, and Zinc Levels in Children with Coronavirus Disease 2019 and Multisystem Inflammatory Syndrome in Children

Objective Vitamin D, due to its immunomodulating effect, zinc, and vitamin A, which affect cellular and humoral immunity, are thought to affect the clinical severity of coronavirus disease 2019 (COVID-19) infection. The present study evaluates the association between vitamin A, D, and zinc deficiencies and disease severity in pediatric patients with COVID-19 infections.

Methods The levels of vitamin A, D, and zinc at the time of diagnosis of 123 pediatric patients who presented to our hospital and were diagnosed as having hospitalized, nonhospitalized COVID-19 infection group, and multisystem inflammatory syndrome in children (MIS-C) were evaluated. The correlations of the measured levels with the disease severity and the need for intensive care or hospitalization were analyzed.

Results Among the 123 patients, 21.1% (n = 26), 42.2% (n = 52), and 36.7% (n = 45) had a diagnosis of MIS-C, belonged to the hospitalized COVID-19 infection group, or belonged to the nonhospitalized COVID-19 infection group, respectively. Zinc levels were significantly lower in the MIS-C group than in the nonhospitalized group (p < 0.05). Vitamin A levels were found to be significantly lower in the MIS-C group than in the nonhospitalized group (p < 0.01) and significantly lower in the hospitalized group when compared with the nonhospitalized group (p < 0.001). Deficiencies in vitamin A, vitamin D, and zinc levels were found to be most common in the MIS-C group (42.3%) and in hospitalized COVID-19 group (15.3%). In the nonhospitalized COVID-19 group, it was found to be the lowest at 6.6%.

Conclusion Based on the results of the present study and a literature review, it can be said that vitamin A, D, and zinc deficiencies may associate with the severity of COVID-19, although more studies are required to clarify this subject further.

Effects of zinc and vitamin A supplementation on prognostic markers and treatment outcomes of adults with pulmonary tuberculosis: a systematic review and meta-analysis

INTRODUCTION

Undernutrition is a major risk factor for tuberculosis (TB), which is estimated to be responsible for 1.9 million TB cases per year globally. The effectiveness of micronutrient supplementation on TB treatment outcomes and its prognostic markers (sputum conversion, serum zinc, retinol and haemoglobin levels) has been poorly understood. This study aimed to determine the effect of zinc and vitamin A supplementation on prognostic markers and TB treatment outcomes among adults with sputum-positive pulmonary TB.

METHODS

A systematic literature search for randomised controlled trials (RCTs) was performed in PubMed, Embase and Scopus databases. Meta-analysis with a random effect model was performed to estimate risk ratio (RR) and mean difference (MD), with a 95% CI, for dichotomous and continuous outcomes, respectively.

RESULTS

Our search identified 2195 records. Of these, nine RCTs consisting of 1375 participants were included in the final analyses. Among adults with pulmonary TB, zinc (RR: 0.94, 95% CI: 0.86 to 1.03), vitamin A (RR: 0.90, 95% CI: 0.80 to 1.01) and combined zinc and vitamin A (RR: 0.98, 95% CI: 0.89 to 1.08) supplementation were not significantly associated with TB treatment success. Combined zinc and vitamin A supplementation was significantly associated with increased sputum smear conversion at 2 months (RR: 1.16, 95% CI: 1.03 to 1.32), serum zinc levels at 2 months (MD: 0.86 μmol/L, 95% CI: 0.14 to 1.57), serum retinol levels at 2 months (MD: 0.06 μmol/L, 95% CI: 0.04 to 0.08) and 6 months (MD: 0.12 μmol/L, 95% CI: 0.10 to 0.14) and serum haemoglobin level at 6 months (MD: 0.29 μg/dL, 95% CI: 0.08 to 0.51), among adults with pulmonary TB.

CONCLUSIONS

Providing zinc and vitamin A supplementation to adults with sputum-positive pulmonary TB during treatment may increase early sputum smear conversion, serum zinc, retinol and haemoglobin levels. However, the use of zinc, vitamin A or both was not associated with TB treatment success.

PROSPERO REGISTRATION NUMBER

CRD42021248548.

Association between fat-soluble vitamins and self-reported health status: a cross-sectional analysis of the MARK-AGE cohort

Self-rated health (SRH) is associated with higher risk of death. Since low plasma levels of fat-soluble vitamins are related to mortality, we aimed to assess whether plasma concentrations of vitamins A, D and E were associated with SRH in the MARK-AGE study. We included 3158 participants (52 % female) aged between 35 and 75 years. Cross-sectional data were collected via questionnaires. An enzyme immunoassay quantified 25-hydroxyvitamin D and HPLC determined α-tocopherol and retinol plasma concentrations. The median 25-hydroxyvitamin D and retinol concentrations differed significantly (P < 0·001) between SRH categories and were lower in the combined fair/poor category v. the excellent, very good and good categories (25-hydroxvitamin D: 40·8 v. 51·9, 49·3, 46·7 nmol/l, respectively; retinol: 1·67 v. 1·75, 1·74, 1·70 µmol/l, respectively). Both vitamin D and retinol status were independently associated with fair/poor SRH in multiple regression analyses: adjusted OR (95 % CI) for the vitamin D insufficiency, deficiency and severe deficiency categories were 1·33 (1·06-1·68), 1·50 (1·17-1·93) and 1·83 (1·34-2·50), respectively; P = 0·015, P = 0·001 and P < 0·001, and for the second/third/fourth retinol quartiles: 1·44 (1·18-1·75), 1·57 (1·28-1·93) and 1·49 (1·20-1·84); all P < 0·001. No significant associations were reported for α-tocopherol quartiles. Lower vitamin A and D status emerged as independent markers for fair/poor SRH. Further insights into the long-term implications of these modifiable nutrients on health status are warranted.

Vitamin A, systemic T-cells, and the eye: Focus on degenerative retinal disease

The first discovered vitamin, vitamin A, exists in a range of forms, primarily retinoids and provitamin carotenoids. The bioactive forms of vitamin A, retinol and retinoic acid, have many critical functions in body systems including the eye and immune system. Vitamin A deficiency is associated with dysfunctional immunity, and presents clinically as a characteristic ocular syndrome, xerophthalmia. The immune functions of vitamin A extend to the gut, where microbiome interactions and nutritional retinoids and carotenoids contribute to the balance of T cell differentiation, thereby determining immune status and contributing to inflammatory disease around the whole body. In the eye, degenerative conditions affecting the retina and uvea are influenced by vitamin A. Stargardt’s disease (STGD1; MIM 248200) is characterised by bisretinoid deposits such as lipofuscin, produced by retinal photoreceptors as they use and recycle a vitamin A-derived chromophore. Age-related macular degeneration features comparable retinal deposits, such as drusen featuring lipofuscin accumulation; and is characterised by parainflammatory processes. We hypothesise that local parainflammatory processes secondary to lipofuscin deposition in the retina are mediated by T cells interacting with dietary vitamin A derivatives and the gut microbiome, and outline the current evidence for this. No cures exist for Stargardt’s or age-related macular degeneration, but many vitamin A-based therapeutic approaches have been or are being trialled. The relationship between vitamin A’s functions in systemic immunology and the eye could be further exploited, and further research may seek to leverage the interactions of the gut-eye immunological axis.

Rice carotenoid biofortification and yield improvement conferred by endosperm-specific overexpression of OsGLK1

Carotenoids, indispensable isoprenoid phytonutrients, are synthesized in plastids and are known to be deficient in rice endosperm. Many studies, involving transgenic manipulations of carotenoid biosynthetic genes, have been performed to obtain carotenoid-enriched rice grains. Nuclear-encoded GOLDEN2-LIKE (GLK) transcription factors play important roles in the regulation of plastid and thylakoid grana development. Here, we show that endosperm-specific overexpression of rice GLK1 gene (OsGLK1) leads to enhanced carotenoid production, increased grain yield, but deteriorated grain quality in rice. Subsequently, we performed the bioengineering of carotenoids biosynthesis in rice endosperm by introducing other three carotenogenic genes, tHMG1, ZmPSY1, and PaCrtI, which encode the enzymes truncated 3-hydroxy-3-methylglutaryl-CoA reductase, phytoene synthase, and phytoene desaturase, respectively. Transgenic overexpression of all four genes (OsGLK1, tHMG1, ZmPSY1, and PaCrtI) driven by rice endosperm-specific promoter GluB-1 established a mini carotenoid biosynthetic pathway in the endosperm and exerted a roughly multiplicative effect on the carotenoid accumulation as compared with the overexpression of only three genes (tHMG1, ZmPSY1, and PaCrtI). In addition, the yield enhancement and quality reduction traits were also present in the transgenic rice overexpressing the selected four genes. Our results revealed that OsGLK1 confers favorable characters in rice endosperm and could help to refine strategies for the carotenoid and other plastid-synthesized micronutrient fortification in bioengineered plants.

Preparation of Apoastaxanthinals and Evaluation of Their Anti-inflammatory Action against Lipopolysaccharide-Stimulated Macrophages and Adipocytes

Apocarotenoids are carotenoid derivatives in which the polyene chain is cleaved via enzymatic or nonenzymatic action. They are found in animal tissues and carotenoid-containing foods. However, limited information on the biological functions of apocarotenoids is available. Here, we prepared apocarotenoids from astaxanthin via chemical oxidation and evaluated their anti-inflammatory action against macrophages and adipocytes. A series of astaxanthin-derived apoastaxanthinals, apo-11-, apo-15-, apo-14'-, apo-12'-, apo-10'-, and apo-8'-astaxanthinals, were successfully characterized by chromatography and spectroscopic analysis. The apoastaxanthinals inhibited inflammatory cytokine production and mRNA expression against lipopolysaccharide-stimulated RAW 264.7 macrophages. Apoastaxanthinals suppressed interleukin-6 overexpression in an in vitro model with macrophages and adipocytes in the following cultures: (1) contact coculture of 3T3-L1 adipocytes and RAW264.7 macrophages and (2) 3T3-L1 adipocytes in a RAW264.7-derived conditioned media. These results indicate that the apoastaxanthinals have the potential for regulation of adipose tissue inflammation observed in obesity.

A novel LC-MS/MS method for the simultaneous analysis of selected fat-soluble vitamins in serum obtained from pediatric patients with pneumonia

Several observational studies have reported associations between low levels of fat-soluble vitamins (A, D and E) and the incidence of pneumonia. Whether infection affects or negatively regulates serum vitamin levels remains controversial. Our aims were to develop and validate a simple-pretreatment and fast method to determine the serum levels of selected fat-soluble vitamins, namely vitamin A (retinol), vitamin D (25-OH-D₃, 25-OH-D₂, and 3-epi-25-OH-D₃), and vitamin E (α-tocopherol), in children suffering from pneumonia during the acute phase and after inflammatory marker recovery. The sample preparation procedure involving protein precipitation and filtration was finished in one step, and separation took 8 min per sample. The calibrations were linear, with R² > 0.99. Both the intra-run (n = 6) and inter-run (n = 3) precision (relative standard deviation, RSD%) values were below 14.61%. The spiked recoveries at 3 concentrations ranged from 80.97 to 111.91%. Accuracies were calibrated using both National Institute of Standards and Technology serum (NIST 968f) and external quality assurance (EQA) samples offered by the National Center of Clinical Laboratories of China, and the relative error (RE%) values ranged from -13.17% to 12.53%. Clinical sample analysis revealed that infection did alter the serum retinol concentration and it did not alter the 25-OH-D and α-tocopherol levels in young children with pneumonia.