Vitamin A supplements for preventing mortality, illness, and blindness in children aged under 5: systematic review and meta-analysis

A review on vitamin A deficiency and depleted immunity in South Asia: From deficiency to resilience

In the developing world, the twin challenges of depleted health and growing issue of food waste management loom large, demanding simultaneous attention and innovative solutions. This review explores how these issues can be effectively mitigated while shedding light on the transformative impact of food waste valorization on health management. A spotlight is cast on vitamin A deficiency (VAD), an acute public health concern, especially prevalent in South Asia, driven by economic constraints, sociocultural factors, inadequate diets, and poor nutrient absorption. VAD's devastating effects are exacerbated by limited education, lack of sanitation, ineffective food regulations, and fragile monitoring systems, disproportionately affecting children and women of childbearing age. Recent studies in South Asian countries have revealed rising rates of illness and death, notably among children and women of childbearing age, due to VAD. To address inadequate dietary intake in children utilizing vegetable waste, particularly from carrots and beetroot, which are rich in β-carotene, and betalains, respectively, offers a sustainable solution. Extracting these compounds from vegetable waste for supplementation, fortification, and dietary diversification could significantly improve public health, addressing both food waste and health disparities economically. This approach presents a compelling avenue for exploration and implementation. In summary, this review presents an integrated approach to tackle health and food waste challenges in the developing world. By tapping into the nutritional treasure troves within vegetable waste, we can enhance health outcomes while addressing food waste, forging a brighter and healthier future for communities in need.

Modeled impacts of bouillon fortification with micronutrients on child mortality in Senegal, Burkina Faso, and Nigeria

Micronutrient interventions can reduce child mortality. By applying Micronutrient Intervention Modeling methods in Senegal, Burkina Faso, and Nigeria, we estimated the impacts of bouillon fortification on apparent dietary adequacy of vitamin A and zinc among children and folate among women. We then used the Lives Saved Tool to predict the impacts of bouillon fortification with ranges of vitamin A, zinc, and folic acid concentrations on lives saved among children 6-59 months of age. Fortification at 250 µg vitamin A/g and 120 µg folic acid/g was predicted to substantially reduce vitamin A- and folate-attributable deaths: 65% for vitamin A and 92% for folate (Senegal), 36% for vitamin A and 74% for folate (Burkina Faso), and >95% for both (Nigeria). Zinc fortification at 5 mg/g would avert 48% (Senegal), 31% (Burkina Faso), and 63% (Nigeria) of zinc-attributable deaths. The addition of all three nutrients at 30% of Codex nutrient reference values in 2.5 g bouillon was predicted to save an annual average of 293 child lives in Senegal (3.5% of deaths from all causes among children 6-59 months of age), 933 (2.1%) in Burkina Faso, and 18,362 (3.7%) in Nigeria. These results, along with evidence on program feasibility and costs, can help inform fortification program design discussions.

Effects of primary or secondary prevention with vitamin A supplementation on clinically important outcomes: a systematic review of randomised clinical trials with meta-analysis and trial sequential analysis

OBJECTIVES

This systematic review with meta-analyses of randomised trials evaluated the preventive effects of vitamin A supplements versus placebo or no intervention on clinically important outcomes, in people of any age.

METHODS

We searched different electronic databases and other resources for randomised clinical trials that had compared vitamin A supplements versus placebo or no intervention (last search 16 April 2024). We used Cochrane methodology. We used the random-effects model to calculate risk ratios (RRs), with 95% CIs. We analysed individually and cluster randomised trials separately. Our primary outcomes were mortality, adverse events and quality of life. We assessed risks of bias in the trials and used Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) to assess the certainty of the evidence.

RESULTS

We included 120 randomised trials (1 671 672 participants); 105 trials allocated individuals and 15 allocated clusters. 92 trials included children (78 individually; 14 cluster randomised) and 28 adults (27 individually; 1 cluster randomised). 14/105 individually randomised trials (13%) and none of the cluster randomised trials were at overall low risk of bias. Vitamin A did not reduce mortality in individually randomised trials (RR 0.99, 95% CI 0.93 to 1.05; I²=32%; p=0.19; 105 trials; moderate certainty), and this effect was not affected by the risk of bias. In individually randomised trials, vitamin A had no effect on mortality in children (RR 0.96, 95% CI 0.88 to 1.04; I²=24%; p=0.28; 78 trials, 178 094 participants) nor in adults (RR 1.04, 95% CI 0.97 to 1.13; I²=24%; p=0.27; 27 trials, 61 880 participants). Vitamin A reduced mortality in the cluster randomised trials (0.84, 95% CI 0.76 to 0.93; I²=66%; p=0.0008; 15 trials, 14 in children and 1 in adults; 364 343 participants; very low certainty). No trial reported serious adverse events or quality of life. Vitamin A slightly increased bulging fontanelle of neonates and infants. We are uncertain whether vitamin A influences blindness under the conditions examined.

CONCLUSIONS

Based on moderate certainty of evidence, vitamin A had no effect on mortality in the individually randomised trials. Very low certainty evidence obtained from cluster randomised trials suggested a beneficial effect of vitamin A on mortality. If preventive vitamin A programmes are to be continued, supporting evidence should come from randomised trials allocating individuals and assessing patient-meaningful outcomes.

PROSPERO REGISTRATION NUMBER

CRD42018104347.

A comprehensive analysis of food insecurity in the drought-prone rural areas of Tigray

BACKGROUND

The number of globally food-insecure people is increasing since 2017. Sub-Saharan Africa has the highest proportion of severely food-insecure people in the world. Tigray region of Ethiopia is one of the food-insecure regions, which, over the past many decades has been affected by recurrent food insecurities. In the drought-prone rural areas of Tigray, many people are living under the condition of chronic hunger. Proper food security studies are vital for proper intervention mechanisms. Yet, previous food security studies have rarely addressed the four pillars of food security: availability, access, utilization, and stability. In this study, all components are duly considered to assess the food insecurity status in the drought-prone rural areas of Tigray, Ethiopia. Of the 34 rural districts in Tigray, 363 households from three drought-prone rural districts were studied.

RESULTS

Household Food Insecurity Access Scale and Food Insecurity Experience Scale were adapted to measure the food availability, access to food, and stability components of food security; and, Household Dietary Diversity Score (HDDS), Food Consumption Score (FCS), mid-upper arm circumference, and Bitot's spot were used to analyze the food utilization aspect. Findings show that 68% of the studied community frequently ate less food than they felt they needed and 82.1% of the households have experienced hunger because of lack of food. The study rural districts were unconnected to road networks; hence, 87.9% of the elderly and 20.4% of the women and girls had no access to food markets. Regarding the food utilization, 81.5% of the studied households had poor FCS; and the average HDDS and FCS for the study areas were 2.47 and 18.9, respectively. The prevalence of Global acute malnutrition, severe acute malnutrition (SAM), and moderate acute malnutrition (MAM) for 6-59 months of age children in the study areas were 50.3, 4.2, and 46.1%, respectively. More notably, the prevalence of SAM for children from the food-insecure households was 21.2%. The prevalence of MAM for pregnant and lactating women (PLW) in the study areas was 59.5. Further, the prevalence of Bitot's spot among 6-59 months of age children was 1.9%. On the other hand, all the rural households had anxiety about their future food demands.

CONCLUSION

The rural households living in the studied areas were critically food-insecure. All the measurements implied that the food insecurity situation in the study areas was unacceptably worrisome and life-threatening. This calls for an instant action to avert the occurrence of famine and starvation in the drought-prone rural areas of Tigray region. Thus, interventions should primarily target the vulnerable rural people and need to be planned based on attaining food availability first rather than concurrently addressing all components of food security. Further, due emphasis should be given to diversifying livelihood strategies of the vulnerable villagers.

Oral vitamin A supplements to prevent acute upper respiratory tract infections in children up to seven years of age

BACKGROUND

According to global prevalence analysis studies, acute upper respiratory tract infections (URTIs) are the most common acute infectious disease in children, especially in preschool children. Acute URTIs lead to an economic burden on families and society. Vitamin A refers to the fat-soluble compound all-trans-retinol and also represents retinol and its active metabolites. Vitamin A interacts with both the innate immune system and the adaptive immune system and improves the host's defences against infections. Correlation studies show that serum retinol deficiency was associated with a higher risk of respiratory tract infections. Therefore, vitamin A supplementation may be important in preventing acute URTIs.

OBJECTIVES

To assess the effectiveness and safety of vitamin A supplements for preventing acute upper respiratory tract infections in children up to seven years of age.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, the Chinese Biomedical Literature Database, and two trial registration platforms to 8 June 2023. We also checked the reference lists of all primary studies and reviewed relevant systematic reviews and trials for additional references. We imposed no language or publication restrictions.

SELECTION CRITERIA

We included randomised controlled trials (RCTs), which evaluated the role of vitamin A supplementation in the prevention of acute URTIs in children up to seven years of age.

DATA COLLECTION AND ANALYSIS

We used the standard methodological procedures expected by Cochrane.

MAIN RESULTS

We included six studies (27,351 participants). Four studies were RCTs and two were cluster-RCTs. The included studies were all conducted in lower-middle-income countries (two in India, two in South Africa, one in Ecuador, and one in Haiti). Three studies included healthy children who had no vitamin A deficiency, one study included children born to HIV-infected women, one study included low-birthweight neonates, and one study included children in areas with a high local prevalence of malnutrition and xerophthalmia. In two studies, vitamin E was a co-treatment administered in addition to vitamin A. We judged the included studies to be at either a high or unclear risk of bias for random sequence generation, incomplete outcome data, and blinding. Primary outcomes Six studies reported the incidence of acute URTIs during the study period. Five studies reported the number of acute URTIs over a period of time, but there was population heterogeneity and the results were presented in different forms, therefore only three studies were meta-analysed. We are uncertain of the effect of vitamin A supplementation on the number of acute URTIs over two weeks (risk ratio (RR) 1.00, 95% confidence interval (CI) 0.92 to 1.09; I2 = 44%; 3 studies, 22,668 participants; low-certainty evidence). Two studies reported the proportion of participants with an acute URTI. We are uncertain of the effect of vitamin A supplementation on the proportion of participants with an acute URTI (2 studies, 15,535 participants; low-certainty evidence). Only one study (116 participants) reported adverse events. No infant in either the placebo or vitamin A group was found to have feeding difficulties (failure to feed or vomiting), a bulging fontanelle, or neurological signs before or after vitamin A administration (very low-certainty evidence). Secondary outcomes Two studies (296 participants) reported the severity of subjective symptoms, presented by the mean duration of acute URTI. Vitamin A may have little to no effect on the mean duration of acute URTI (very low-certainty evidence).

AUTHORS' CONCLUSIONS

The evidence for the use of vitamin A supplementation to prevent acute URTI is uncertain, because population, dose and duration of interventions, and outcomes vary between studies. From generally very low- to low-certainty evidence, we found that there may be no benefit in the use of vitamin A supplementation to prevent acute URTI in children up to seven years of age. More RCTs are needed to strengthen the current evidence. Future research should report over longer time frames using validated tools and consistent reporting, and ensure adequate power calculations, to allow for easier synthesis of data. Finally, it is important to assess vitamin A supplementation for preschool children with vitamin A deficiency.

Bilateral bartholin's gland abscesses in a 4-year-old girl with vitamin a deficiency: a case report

BACKGROUND

A Bartholin's gland abscess is one of the most common infections in women of reproductive age. Although Bartholin's gland abscesses have been reported in prepubertal children, they are rarer in prepubertal children than in adults. Herein, we report a case of bilateral Bartholin's gland abscesses in a 4-year-old girl with vitamin A deficiency.

CASE PRESENTATION

A 4-year-old girl diagnosed with autism spectrum disorder was admitted to the hospital for close examination and treatment because of persistent fever and malaise. The child was a marked fussy eater and was diagnosed with corneal ulceration and night blindness secondary to vitamin A deficiency. Both of the patient's labia were swollen, and a diagnosis of a bilateral Bartholin's gland abscess was made using computed tomography. Incisional drainage was performed under general anesthesia. The patient's postoperative course was uneventful, and she was discharged from the hospital on day 8 after the surgery. During hospitalization, attempts were made to correct the vitamin deficiency by adding nutritional supplements to the diet. Three months after the surgery, no recurrence of abscesses was noted.

CONCLUSIONS

Decreased immunocompetence and mucosal barrier function due to vitamin A deficiency is thought to be the underlying cause of Bartholin's gland abscesses. Although prepubertal Bartholin's gland abscesses have been reported, they are rare. To the best of our knowledge, no reports of bilateral Bartholin's gland abscesses potentially caused by vitamin A deficiency have been reported. When prepubertal girls present with Bartholin's gland abscesses, the presence of immunodeficiency due to vitamin or trace element deficiency should also be considered.

SKN-1/NRF2 upregulation by vitamin A is conserved from nematodes to mammals and is critical for lifespan extension in Caenorhabditis elegans

Vitamin A (VA) is a micronutrient essential for the physiology of many organisms, but its role in longevity and age-related diseases remains unclear. In this work, we used Caenorhabditis elegans to study the impact of various bioactive compounds on lifespan. We demonstrate that VA extends lifespan and reduces lipofuscin and fat accumulation while increasing resistance to heat and oxidative stress. This resistance can be attributed to high levels of detoxifying enzymes called glutathione S-transferases, induced by the transcription factor skinhead-1 (SKN-1). Notably, VA upregulated the transcript levels of skn-1 or its mammalian ortholog NRF2 in both C. elegans, human cells, and liver tissues of mice. Moreover, the loss-of-function genetic models demonstrated a critical involvement of the SKN-1 pathway in longevity extension by VA. Our study thus provides novel insights into the molecular mechanism of anti-aging and anti-oxidative effects of VA, suggesting that this micronutrient could be used for the prevention and/or treatment of age-related disorders.

Cross-country health inequalities of four common nutritional deficiencies among children, 1990 to 2019: data from the Global Burden of Disease Study 2019

BACKGROUND

Nutritional deficiencies remain serious medical and public health issues worldwide, especially in children. This study aims to analyze cross-country inequality in four common nutritional deficiencies (protein-energy malnutrition, dietary iron deficiency, vitamin A deficiency and iodine deficiency) among children from 1990 to 2019 based on Global Burden of Disease (GBD) 2019 data.

METHODS

Prevalence and disability-adjusted life years (DALYs) data as measures of four nutritional deficiency burdens in people aged 0 to 14 years were extracted from the GBD Results Tool. We analyzed temporal trends in prevalence by calculating the average annual percent change (AAPC) and quantified cross-country inequalities in disease burden using the slope index.

RESULTS

Globally, the age-standardized prevalence rates of dietary iron deficiency, vitamin A deficiency and iodine deficiency decreased, with AAPCs of -0.14 (-0.15 to -0.12), -2.77 (-2.96 to -2.58), and -2.17 (-2.3 to -2.03) from 1999 to 2019, respectively. Significant reductions in socio-demographic index (SDI)-related inequality occurred in protein-energy malnutrition and vitamin A deficiency, while the health inequality for dietary iron deficiency and iodine deficiency remained basically unchanged. The age-standardized prevalence and DALY rates of the four nutritional deficiencies decreased as the SDI and healthcare access and quality index increased.

CONCLUSIONS

The global burden of nutritional deficiency has decreased since 1990, but cross-country health inequalities still exist. More efficient public health measures are needed to reduce disease burdens, particularly in low-SDI countries/territories.

Hepatic Vitamin A Concentrations and Association with Infectious Causes of Child Death

OBJECTIVES

To assess postmortem vitamin A (VA) concentrations in children under 5 years of age and evaluate the association between VA deficiency (VAD) and infectious causes of death (CoD).

STUDY DESIGN

In this cross-sectional study from the Child Health and Mortality Prevention Surveillance (CHAMPS) Network, liver biopsies collected within 72 hours of death were analyzed from 405 stillbirths and children under 5 years in Kenya and South Africa. Total liver VA (TLVA) concentrations were quantified using ultra-performance liquid chromatography, and cutoffs of ≤0.1 μmol/g, >0.1 to <0.7 μmol/g, ≥0.7 to <1.0 μmol/g, and ≥1.0 μmol/g were used to define VAD, adequate VA status, high VA, and hypervitaminosis A, respectively. CoD were determined by expert panel review.

RESULTS

Among 366 liver samples with viable extraction, pooled prevalences of VAD, adequacy, high VA, and hypervitaminosis were 34.2%, 51.1%, 6.0%, and 8.7%, respectively. VAD was more common among neonates compared with stillbirths, infants, or children, and among those with low birthweight (LBW), underweight, or stunting (P < .05). When adjusting for site, age, and sex, there was no significant association of VAD with increased infectious CoD (OR 1.9, 95% confidence interval [CI] 0.9, 3.8, P = .073). In stratified analyses, VA deficient boys, but not girls, had an increased risk of infectious CoD (OR 3.4, 95% CI 1.3, 10.3, P = .013).

CONCLUSIONS

Definitive postmortem assessment of VA status identified both VAD and VA excess among children under 5 years of age in Kenya and South Africa. VAD in boys was associated with increased risk of infectious mortality. Our findings may inform a transition from universal VA supplementation (VAS) to targeted strategies in certain countries.

Effectiveness of intermittent iron and high-dose vitamin A supplementation on cognitive development of school children in southern Ethiopia: a randomized placebo-controlled trial

BACKGROUND

Iron is an essential mineral whose deficiency results in cognitive alteration, impaired emotional behaviors, and altered myelination and neurotransmission. In animal models, it has been shown that vitamin A (VA) could affect cognition.

OBJECTIVES

The study aimed to evaluate the effectiveness of intermittent iron and VA supplementation on cognitive development of schoolchildren, and to assess the interaction between these supplementations.

METHODS

Considering a 2 × 2 factorial design, 504 children were randomly assigned to 1 of the 4 arms: placebo VA and placebo iron supplement; high-dose vitamin VA and placebo iron supplement; iron supplement and placebo VA; and iron and high-dose vitamin VA supplements. Cognitive development was assessed using Raven's Coloured Progressive Matrices, digit span, Tower of London, and visual search tasks.

RESULTS

The mean [± standard deviation (SD)] age of the enrolled children was 9.6 (±1.6) y. One-fifth of the children had iron deficiency or anemia, whereas 2.9%, 3.9%, and 12.1% of children had low iron stores, iron deficiency anemia, and VA deficiency, respectively. Intermittent iron supplementation did not result in any significant improvement of children's cognitive development and had a negative effect on the performance index of the visual search task compared with placebo (-0.17 SD, 95% confidence interval: -0.32, -0.02). Effects were evident among children with stunting, thinness, or children coming from understimulating home environments. High-dose VA supplementation resulted in a significant improvement of digit span z-score with a mean difference of 0.30 SD (95% confidence interval: 0.14, 0.46) compared with placebo VA. VA had a more beneficial impact for girls, children infected with helminths, and those from food secure households.

CONCLUSION

In a population where the prevalence of iron deficiency is low, intermittent iron supplementation did not have any or negative effect on the child's cognitive development outcomes. Conversely, VA supplementation improved the child's working memory.

TRIAL REGISTRATION NUMBER

The study is registered at clinicaltrials.gov as NCT04137354 (https://clinicaltrials.gov/study/NCT04137354).

Population-Level Risk Factors Related to Measles Case Fatality: A Conceptual Framework Based on Expert Consultation and Literature Review

A better understanding of population-level factors related to measles case fatality is needed to estimate measles mortality burden and impact of interventions such as vaccination. This study aimed to develop a conceptual framework of mechanisms associated with measles case fatality ratios (CFRs) and assess the scope of evidence available for related indicators. Using expert consultation, we developed a conceptual framework of mechanisms associated with measles CFR and identified population-level indicators potentially associated with each mechanism. We conducted a literature review by searching PubMed on 31 October 2021 to determine the scope of evidence for the expert-identified indicators. Studies were included if they contained evidence of an association between an indicator and CFR and were excluded if they were from non-human studies or reported non-original data. Included studies were assessed for study quality. Expert consultation identified five mechanisms in a conceptual framework of factors related to measles CFR. We identified 3772 studies for review and found 49 studies showing at least one significant association with CFR for 15 indicators (average household size, educational attainment, first- and second-dose coverage of measles-containing vaccine, human immunodeficiency virus prevalence, level of health care available, stunting prevalence, surrounding conflict, travel time to major city or settlement, travel time to nearest health care facility, under-five mortality rate, underweight prevalence, vitamin A deficiency prevalence, vitamin A treatment, and general malnutrition) and only non-significant associations for five indicators (antibiotic use for measles-related pneumonia, malaria prevalence, percent living in urban settings, pneumococcal conjugate vaccination coverage, vitamin A supplementation). Our study used expert consultation and a literature review to provide additional insights and a summary of the available evidence of these underlying mechanisms and indicators that could inform future measles CFR estimations.

Correlates of Iron, Cobalamin, Folate, and Vitamin A Status among Stunted Children: A Cross-Sectional Study in Uganda

Micronutrient deficiencies and stunting are prevalent. We assessed correlates of iron, cobalamin, folate, and vitamin A biomarkers in a cross-sectional study of stunted children aged 12-59 months in eastern Uganda. The biomarkers measured were serum ferritin (S-FE), soluble transferrin receptor (S-TfR), retinol binding protein (S-RBP), plasma cobalamin (P-Cob), methylmalonic acid (P-MMA), and folate (P-Fol). Using linear regression, we assessed socio-demography, stunting severity, malaria rapid test, and inflammation as correlates of micronutrient biomarkers. Of the 750 children, the mean (SD) age was 32.0 (11.7) months, and 45% were girls. Iron stores were depleted (inflammation-corrected S-FE < 12 µg/L) in 43%, and 62% had tissue iron deficiency (S-TfR > 8.3 mg/L). P-Cob was low (<148 pmol/L) and marginal (148-221 pmol/L) in 3% and 20%, and 16% had high P-MMA (>0.75 µmol/L). Inflammation-corrected S-RBP was low (<0.7 µmol/L) in 21% and P-Fol (<14 nmol/L) in 1%. Age 24-59 months was associated with higher S-FE and P-Fol and lower S-TfR. Breastfeeding beyond infancy was associated with lower iron status and cobalamin status, and malaria was associated with lower cobalamin status and tissue iron deficiency (higher S-TfR) despite iron sequestration in stores (higher S-FE). In conclusion, stunted children have iron, cobalamin, and vitamin A deficiencies. Interventions addressing stunting should target co-existing micronutrient deficiencies.

Diet and ideal food pyramid to prevent or support the treatment of diabetic retinopathy, age-related macular degeneration, and cataracts

Many eye diseases, such as diabetic retinopathy (DR), age-related macular degeneration (AMD), and cataracts are preventable and treatable with lifestyle. The objective of this review is to assess the most recent research on the ideal dietary approach to prevent or support the treatment of DR, AMD, and cataracts, as well as to construct a food pyramid that makes it simple for people who are at risk of developing these pathologies to decide what to eat. The food pyramid presented here proposes what should be consumed every day: 3 portions of low glycemic index (GI) grains (for fiber and zinc content), 5 portions (each portion: ≥200 g/day) of fruits and vegetables (spinach, broccoli, zucchini cooked, green leafy vegetables, orange, kiwi, grapefruit for folic acid, vitamin C, and lutein/zeaxanthin content, at least ≥42 μg/day, are to be preferred), extra virgin olive (EVO) oil (almost 20 mg/day for vitamin E and polyphenols content), nuts or oil seeds (20-30 g/day, for zinc content, at least ≥15.8 mg/day); weekly: fish (4 portions, for omega-3 content and eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA) 0.35-1.4 g/day), white meat (3 portions for vitamin B12 content), legumes (2 portions for vegetal proteins), eggs (2 portions for lutein/zeaxanthin content), light cheeses (2 portions for vitamin B6 content), and almost 3-4 times/week microgreen and spices (saffron and curcumin). At the top of the pyramid, there are two pennants: one green, which indicates the need for personalized supplementation (if daily requirements cannot be met through diet, omega-3, and L-methylfolate supplementation), and one red, which indicates that certain foods are prohibited (salt and sugar). Finally, 3-4 times per week, 30-40 min of aerobic and resistance exercises are required.

Interventions addressing maternal and child health among the urban poor and homeless: an overview of systematic reviews

BACKGROUND

Inequalities in access to and utilization of maternal and child health (MCH) care are hampering progress on the path to achieving the Sustainable Development Goals. In a number of Low- and Middle-Income Countries (LMICs) population subgroups at disproportionate risk of being left behind are the urban poor. Within this neglected group is the further neglected group of the homeless. Concomitantly, a number of interventions from the antenatal period onward have been piloted, tested, and scaled in these contexts. We carried out an overview of systematic reviews (SRs) to characterize the evidence around maternal and child health interventions relevant to urban poor homeless populations in LMICs.

METHODS

We searched Medline, Cochrane Library, Health Systems Evidence and EBSCOhost databases for SRs published between January 2009 and 2020 (with an updated search through November 2021). Our population of interest was women or children from urban poor settings in LMICs; interventions and outcomes corresponded with the World Health Organization's (WHO) guidance document. Each SR was assessed by two reviewers using established standard critical appraisal checklists. The overview was registered in PROSPERO (ID: CRD42021229107).

RESULTS

In a sample of 33 high quality SRs, we found no direct relevant evidence for pregnant and lactating homeless women (and children) in the reviewed literature. There was a lack of emphasis on evidence related to family planning, safe abortion care, and postpartum care of mothers. There was mixed quality evidence that the range of nutritional interventions had little, unclear or no effect on several child mortality and development outcomes. Interventions related to water, sanitation, and hygiene, ensuring acceptability of community health services and health promotion type programs could be regarded as beneficial, although location seemed to matter. Importantly, the risk of bias reporting in different reviews did not match, suggesting that greater attention to rigour in their conduct is needed.

CONCLUSION

The generalizability of existing systematic reviews to our population of interest was poor. There is a clear need for rigorous primary research on MCH interventions among urban poor, and particularly homeless populations in LMICs, as it is as yet unclear whether the same, augmented, or altogether different interventions would be required.

Carotenoids: Role in Neurodegenerative Diseases Remediation

Numerous factors can contribute to the development of neurodegenerative disorders (NDs), such as Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, Huntington's disease, and multiple sclerosis. Oxidative stress (OS), a fairly common ND symptom, can be caused by more reactive oxygen species being made. In addition, the pathological state of NDs, which includes a high number of protein aggregates, could make chronic inflammation worse by activating microglia. Carotenoids, often known as "CTs", are pigments that exist naturally and play a vital role in the prevention of several brain illnesses. CTs are organic pigments with major significance in ND prevention. More than 600 CTs have been discovered in nature, and they may be found in a wide variety of creatures. Different forms of CTs are responsible for the red, yellow, and orange pigments seen in many animals and plants. Because of their unique structure, CTs exhibit a wide range of bioactive effects, such as anti-inflammatory and antioxidant effects. The preventive effects of CTs have led researchers to find a strong correlation between CT levels in the body and the avoidance and treatment of several ailments, including NDs. To further understand the connection between OS, neuroinflammation, and NDs, a literature review has been compiled. In addition, we have focused on the anti-inflammatory and antioxidant properties of CTs for the treatment and management of NDs.

Oral vitamin A supplements to prevent acute upper respiratory tract infections in children up to seven years of age

This is a protocol for a Cochrane Review (intervention). The objectives are as follows:

To assess the effectiveness and safety of vitamin A supplements for preventing acute upper respiratory tract infections in children up to seven years of age.

Vitamin A Ameliorated Irinotecan-Induced Diarrhea in a Piglet Model Involving Enteric Glia Modulation and Immune Cells Infiltration

Vitamin A (VA) and its metabolite, retinoic acid (RA), play important roles in modulating intestinal mucosal immunity, yet little is known about their regulatory effects on enteric nervous system function. The study aims to explore the protective effects of dietary VA on diarrhea in a piglet model involving enteric glia and immune cell modulation. Twenty-eight weaned piglets were fed either the basal or VA (basal diet supplemented with 18,000 IU/kg VA) diet and with or without irinotecan (CPT-11) injection. CPT-11 induced increased diarrhea incidence, immune infiltration, and reactive enteric gliosis. A diet supplemented with 18,000 IU/kg VA ameliorated the adverse effects of CPT-11 on the gut barrier. VA reduced diarrhea incidence and attenuated enteric glial gliosis, immune cell infiltrations, and inflammatory responses of CPT-induced piglets. An in vitro experiment with 1 nmol/L RA showed direct protective effects on monocultures of enteric glial cells (EGCs) or macrophages in LPS-simulated inflammatory conditions. Furthermore, 1 ng/mL glial-derived neurotropic factors (GDNF) could inhibit M1-macrophage polarization and pro-inflammatory cytokines production. In summary, VA exerted protective effects on the intestinal barrier by modulating enteric glia and immune cells, perhaps enhancing epithelial recovery under CPT-11 challenge. Our study demonstrated that RA signaling might promote the roles of enteric glia in intestinal immunity and tissue repair, which provided a reference for the VA supplementation of patient diets.

Rhodotorula mucilaginosa-alternative sources of natural carotenoids, lipids, and enzymes for industrial use

Biotechnologically useful yeast strains have been receiving important attention worldwide for the demand of a wide range of industries. Rhodotorula mucilaginosa is recognized as a biotechnologically important yeast that has gained great interest as a promising platform strain, owing to the diverse substrate appetites, robust stress resistance, and other gratifying features. Due to its attractive properties, R. mucilaginosa has been regarded as an excellent candidate for the biorefinery of carotenoids, lipids, enzymes, and other functional bioproducts by utilizing low-cost agricultural waste materials as substrates. These compounds have aroused great interest as the potential alternative sources of health-promoting food products, substrates for so-called third-generation biodiesel, and dyes or functional ingredients for cosmetics. Furthermore, the use of R. mucilaginosa has rapidly increased as a result of advancements in fermentation for enhanced production of these valuable bioactive compounds. This review focuses on R. mucilaginosa in these advancements and summarizes its potential prospects as alternative sources of natural bioproducts.

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.

Role of Vitamin A Supplementation in Prevention and Control of Coronavirus Disease-19: A Narrative Review

Coronavirus disease-19 (COVID-19) caused by SARS-CoV-2 is a novel viral infectious disease, which broke out in the end of winter season 2019 in China and soon became a pandemic. Characteristically there was severe local and systemic immune-inflammatory response to the virus, damaging the respiratory system and other organ systems. The morbidity and mortality caused by the disease are producing tremendous impact on health. The understanding about pathogenesis and manifestations of the disease was obscure. To date, no classic treatment or preventive measure was available for COVID-19 other than symptomatic and supportive care or few drugs under trial. A possibility exists that maintaining vitamin A adequate levels can protect the affected respiratory mucosa, increase antimicrobial activity, produce better antibody response, and have antiinflammatory effects, thereby promoting repair and healing as well. It has been discussed in the review that by various mechanisms, immune regulation through vitamin A supplementation is beneficial to boost immunity in the current outbreak situation when the population is susceptible to the disease. There is a high possibility that vitamin A supplementation to cases as well as population at risk of COVID-19 has a key role in prevention and control. Hence, it is believed that along with other therapeutic and preventive measures, maintaining vitamin A sufficiency during and prior to the development of active disease may act as an adjuvant in population at risk and cases to prevent and control COVID-19.

Estimates of child mortality reductions attributed to vitamin A supplementation in sub-Saharan Africa: scale up, scale back, or refocus?

BACKGROUND

Vitamin A supplementation (VAS) has been implemented in over 82 countries globally, primarily because of its beneficial effect in preventing child mortality. Secular reductions in child mortality and the implementation of alternative programs to promote vitamin A intake have led to questions on the need for national VAS programs.

OBJECTIVES

This study aimed to estimate child mortality changes related to VAS using current, scale-back, and scale-up coverage scenarios.

METHODS

Data related to demographic characteristics, fertility, intervention coverage, anthropometry, child mortality and cause-of-death structure were integrated into the Lives Saved Tool (LiST). We estimated the cause-specific (LiST model) and all-cause mortality reductions related to VAS based on evidence from recent meta-analyses.

RESULTS

Between 2008 and 2018, VAS coverage declined in most sub-Saharan African (SSA) countries. In 2019 alone, 12% and 24% reductions in all-cause mortality related to VAS were expected to avert from 105,332 to 234,704 child deaths, respectively, in SSA; whereas the cause-specific mortality model (LiST) estimated that 141,670 child deaths were averted in 2019. Estimates of VAS-related child mortality reductions were highly variable among countries. Our scaling-back scenario led to highly variable country-level results, with expected increases in mortality rates, from a low of 0.04/1000 live births to as high as 49.3/1000 live births, suggesting that some countries could start considering scaling back, while others need to scale up.

CONCLUSIONS

Excess child mortality that would be preventable by VAS has declined, but is still significant in many SSA countries. While scale-up of VAS is needed for most of the countries, scaling back can also be considered in some countries. Policy decisions, however, should be guided by more recent data on food consumption, vitamin A statuses, child health, and vitamin A fortification coverage.

Efficient production of retinol in Yarrowia lipolytica by increasing stability using antioxidant and detergent extraction

The demand for bio-based retinol (vitamin A) is currently increasing, however its instability represents a major bottleneck in microbial production. Here, we developed an efficient method to selectively produce retinol in Yarrowia lipolytica. The β-carotene 15,15'-dioxygenase (BCO) cleaves β-carotene into retinal, which is reduced to retinol by retinol dehydrogenase (RDH). Therefore, to produce retinol, we first generated β-carotene-producing strain based on a high-lipid-producer via overexpressing genes including heterologous β-carotene biosynthetic genes, GGS1^F43I mutant of endogenous geranylgeranyl pyrophosphate synthase isolated by directed evolution, and FAD1 encoding flavin adenine dinucleotide synthetase, while deleting several genes previously known to be beneficial for carotenoid production. To produce retinol, 11 copies of BCO gene from marine bacterium 66A03 (Mb.Blh) were integrated into the rDNA sites of the β-carotene overproducer. The resulting strain produced more retinol than retinal, suggesting strong endogenous promiscuous RDH activity in Y. lipolytica. The introduction of Mb.BCO led to a considerable reduction in β-carotene level, but less than 5% of the consumed β-carotene could be detected in the form of retinal or retinol, implying severe degradation of the produced retinoids. However, addition of the antioxidant butylated hydroxytoluene (BHT) led to a >20-fold increase in retinol production, suggesting oxidative damage is the main cause of intracellular retinol degradation. Overexpression of GSH2 encoding glutathione synthetase further improved retinol production. Raman imaging revealed co-localization of retinol with lipid droplets, and extraction of retinol using Tween 80 was effective in improving retinol production. By combining BHT treatment and extraction using Tween 80, the final strain CJ2104 produced 4.86 g/L retinol and 0.26 g/L retinal in fed-batch fermentation in a 5-L bioreactor, which is the highest retinol production titer ever reported. This study demonstrates that Y. lipolytica is a suitable host for the industrial production of bio-based retinol.

Effect of a Fortified Dairy-Based Drink on Micronutrient Status, Growth, and Cognitive Development of Nigerian Toddlers- A Dose-Response Study

Malnutrition results in a high prevalence of stunting, underweight, and micronutrient deficiencies. This study investigated the effect of a multi-nutrient fortified dairy-based drink on micronutrient status, growth, and cognitive development in malnourished [height-for-age z-score (HAZ) and/or weight-for-age z-score (WAZ) < -1 SD and >−3 SD] Nigerian toddlers (n = 184, 1–3 years). The product was provided in different daily amounts (200, 400, or 600 ml) for 6 months. At baseline and endline, venous blood and urine samples were collected to determine micronutrient status. Bodyweight, height, waist, and head circumference were measured, and corresponding Z-scores were calculated. The Bayley-III Screening Test was used to classify the cognitive development of the children. In a modified per-protocol (PP) population, the highest prevalence's of micronutrient deficiencies were found for vitamin A (35.5%) and selenium (17.9%). At endline, there were no significant improvements in iodine, zinc, vitamin B12, and folate status in any of the three groups. Regarding vitamin D status (25OHD), consumption of 600 and 400 ml resulted in an improved status as compared to baseline, and in a difference between the 600- and 200-ml groups. Consumption of 600 ml also increased vitamin A and selenium status as compared to baseline, but no differences were found between groups. Within the groups, WAZ, weight-for-height z-score (WHZ), and BMI-for-age z-score (BAZ) improved, but without differences between the groups. For HAZ, only the 600 ml group showed improvement within the group, but it was not different between groups. For the absolute weight, height, and head circumference only trends for differences between groups were indicated. Cognition results did not differ between the groups. Within groups, all showed a decline in the per cent of competent children for receptive language. To study the effects of a nutritional intervention on linear growth and cognition, a longer study duration might be necessary. Regarding the improvement of micronutrient status, 600 ml of fortified dairy-based drink seems most effective.

Vitamin A supplementation for preventing morbidity and mortality in children from six months to five years of age

BACKGROUND

Vitamin A deficiency (VAD) is a major public health problem in low- and middle-income countries, affecting 190 million children under five years of age and leading to many adverse health consequences, including death. Based on prior evidence and a previous version of this review, the World Health Organization has continued to recommend vitamin A supplementation (VAS) for children aged 6 to 59 months. The last version of this review was published in 2017, and this is an updated version of that review.

OBJECTIVES

To assess the effects of vitamin A supplementation (VAS) for preventing morbidity and mortality in children aged six months to five years.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, six other databases, and two trials registers up to March 2021. We also checked reference lists and contacted relevant organisations and researchers to identify additional studies.

SELECTION CRITERIA

Randomised controlled trials (RCTs) and cluster-RCTs evaluating the effect of synthetic VAS in children aged six months to five years living in the community. We excluded studies involving children in hospital and children with disease or infection. We also excluded studies evaluating the effects of food fortification, consumption of vitamin A rich foods, or beta-carotene supplementation.

DATA COLLECTION AND ANALYSIS

For this update, two review authors independently assessed studies for inclusion resolving discrepancies by discussion. We performed meta-analyses for outcomes, including all-cause and cause-specific mortality, disease, vision, and side effects. We used the GRADE approach to assess the quality of the evidence.

MAIN RESULTS

The updated search identified no new RCTs. We identified 47 studies, involving approximately 1,223,856 children. Studies were set in 19 countries: 30 (63%) in Asia, 16 of these in India; 8 (17%) in Africa; 7 (15%) in Latin America, and 2 (4%) in Australia. About one-third of the studies were in urban/periurban settings, and half were in rural settings; the remaining studies did not clearly report settings. Most studies included equal numbers of girls and boys and lasted about one year. The mean age of the children was about 33 months. The included studies were at variable overall risk of bias; however, evidence for the primary outcome was at low risk of bias. A meta-analysis for all-cause mortality included 19 trials (1,202,382 children). At longest follow-up, there was a 12% observed reduction in the risk of all-cause mortality for VAS compared with control using a fixed-effect model (risk ratio (RR) 0.88, 95% confidence interval (CI) 0.83 to 0.93; high-certainty evidence). Nine trials reported mortality due to diarrhoea and showed a 12% overall reduction for VAS (RR 0.88, 95% CI 0.79 to 0.98; 1,098,538 children; high-certainty evidence). There was no evidence of a difference for VAS on mortality due to measles (RR 0.88, 95% CI 0.69 to 1.11; 6 studies, 1,088,261 children; low-certainty evidence), respiratory disease (RR 0.98, 95% CI 0.86 to 1.12; 9 studies, 1,098,538 children; low-certainty evidence), and meningitis. VAS reduced the incidence of diarrhoea (RR 0.85, 95% CI 0.82 to 0.87; 15 studies, 77,946 children; low-certainty evidence), measles (RR 0.50, 95% CI 0.37 to 0.67; 6 studies, 19,566 children; moderate-certainty evidence), Bitot's spots (RR 0.42, 95% CI 0.33 to 0.53; 5 studies, 1,063,278 children; moderate-certainty evidence), night blindness (RR 0.32, 95% CI 0.21 to 0.50; 2 studies, 22,972 children; moderate-certainty evidence), and VAD (RR 0.71, 95% CI 0.65 to 0.78; 4 studies, 2262 children, moderate-certainty evidence). However, there was no evidence of a difference on incidence of respiratory disease (RR 0.99, 95% CI 0.92 to 1.06; 11 studies, 27,540 children; low-certainty evidence) or hospitalisations due to diarrhoea or pneumonia. There was an increased risk of vomiting within the first 48 hours of VAS (RR 1.97, 95% CI 1.44 to 2.69; 4 studies, 10,541 children; moderate-certainty evidence).

AUTHORS' CONCLUSIONS

This update identified no new eligible studies and the conclusions remain the same. VAS is associated with a clinically meaningful reduction in morbidity and mortality in children. Further placebo-controlled trials of VAS in children between six months and five years of age would not change the conclusions of this review, although studies that compare different doses and delivery mechanisms are needed. In populations with documented VAD, it would be unethical to conduct placebo-controlled trials.

Global, regional, and national burdens of common micronutrient deficiencies from 1990 to 2019: A secondary trend analysis based on the Global Burden of Disease 2019 study

BACKGROUND

Understanding micronutrient deficiency burdens and trends can help guide effective intervention strategies. This study aims to elucidate trends in common micronutrient deficiencies, in particular, dietary iron, iodine and vitamin A deficiencies, from 1990 to 2019 using Global Burden of Disease (GBD) 2019 study data.

METHODS

We analyzed data from the GBD 2019 study to calculate the prevalence, incidence, and disability-adjusted life year (DALY) rates of micronutrient deficiencies in geographic populations worldwide from 1990 to 2019. The estimated annual percentage changes (EAPCs) and age-standardized rates were calculated to evaluate the temporal trends.

FINDINGS

Globally, the age-standardized prevalence rates of iodine deficiency, vitamin A deficiency, and dietary iron deficiency decreased, with EAPCs of -0.690 (95% CI, -0.842 to -0.538), -3.15 (95% CI, -3.20 to -3.02), and -0.546 (95% CI, -0.585 to -0.507) between 1999 and 2019, respectively. Regarding the sociodemographic index (SDI), the highest age-standardized prevalence, incidence, and DALY rates of micronutrient deficiency were found in low-SDI countries in 2019. There were linear associations between the SDI and the healthcare access and quality (HAQ) index and age-standardized prevalence, incidence, and DALY rates.

INTERPRETATION

Global micronutrient deficiency burdens have decreased since 1990. The potential burden of iodine deficiency in some developed countries is worthy of attention. The results of this study could guide policy makers in implementing cost-effective interventions to reduce micronutrient deficiency burdens, particularly in low-SDI and low-HAQ index countries.

FUNDING

This work was supported by the National Natural Science Foundation of China (Grant No. 82000753) and the China Postdoctoral Science Foundation (Grant No. 2021MD703910).

Association between Circulating Antioxidants and Longevity: Insight from Mendelian Randomization Study

Background. Antioxidants attracted long-standing attention as promising preventive agents worldwide. Previous observational studies have reported that circulating antioxidants are associated with reduced mortality; however, randomized clinical trials indicate neutral or harmful impacts. The association of long-term circulating antioxidant exposure with longevity is still unclear. Objectives. We aim to determine whether long-term circulating antioxidant exposure is causally associated with longevity in the general population using the two-sample Mendelian randomization (MR) design. Methods. Genetic instruments for circulating antioxidants (ascorbate, lycopene, selenium, beta-carotene, and retinol) and antioxidant metabolites (ascorbate, alpha-tocopherol, gamma-tocopherol, and retinol) were identified from the largest up-to-date genome-wide association studies (GWASs). Summary statistics of these instruments with individual survival to the 90th vs. 60th percentile age (11,262 cases and 25,483 controls) and parental lifespan ( $N=\mathrm{1,012,240}$ individuals) were extracted. The causal effect was estimated using the inverse-variance weighted method in the main analysis and complemented by multiple sensitivity analyses to test the robustness of results. Results. We found that genetically determined higher concentration of circulating retinol (vitamin A) metabolite was casually associated with a higher odds of longevity (OR, 1.07; 95% CI, 1.02–1.13; $P<0.01$ ) and increased parental lifespan (lifespan years per 10-fold increase: 0.17; 95% CI, 0.07–0.27; $P<0.01$ ). Present evidence did not support a causal impact of circulating ascorbate (vitamin C), tocopherol (vitamin E), lycopene, selenium or beta-carotene on life expectancy. No evidence was identified to show the pleiotropic effects had biased the results. Conclusions. Long-term higher exposure to retinol metabolite is causally associated with longevity in the general population. Future MR analyses could assess the current findings further by utilizing additional genetic variants and greater samples from large-scale GWASs.

Metabolic and nutritional triggers associated with increased risk of liver complications in SARS-CoV-2

Obesity, diabetes, cardiovascular and respiratory diseases, cancer and smoking are risk factors for negative outcomes in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which can quickly induce severe respiratory failure in 5% of cases. Coronavirus disease-associated liver injury may occur during progression of SARS-CoV-2 in patients with or without pre-existing liver disease, and damage to the liver parenchyma can be caused by infection of hepatocytes. Cirrhosis patients may be particularly vulnerable to SARS-CoV-2 if suffering with cirrhosis-associated immune dysfunction. Furthermore, pharmacotherapies including macrolide or quinolone antibiotics and steroids can also induce liver damage. In this review we addressed nutritional status and nutritional interventions in severe SARS-CoV-2 liver patients. As guidelines for SARS-CoV-2 in intensive care (IC) specifically are not yet available, strategies for management of sepsis and SARS are suggested in SARS-CoV-2. Early enteral nutrition (EN) should be started soon after IC admission, preferably employing iso-osmolar polymeric formula with initial protein content at 0.8 g/kg per day progressively increasing up to 1.3 g/kg per day and enriched with fish oil at 0.1 g/kg per day to 0.2 g/kg per day. Monitoring is necessary to identify signs of intolerance, hemodynamic instability and metabolic disorders, and transition to parenteral nutrition should not be delayed when energy and protein targets cannot be met via EN. Nutrients including vitamins A, C, D, E, B6, B12, folic acid, zinc, selenium and ω-3 fatty acids have in isolation or in combination shown beneficial effects upon immune function and inflammation modulation. Cautious and monitored supplementation up to upper limits may be beneficial in management strategies for SARS-CoV-2 liver patients.

All trans retinoic acid as a host-directed immunotherapy for tuberculosis

Tuberculosis (TB) is the top bacterial infectious disease killer and one of the top ten causes of death worldwide. The emergence of strains of multiple drug-resistant tuberculosis (MDR-TB) has pushed our available stock of anti-TB agents to the limit of effectiveness. This has increased the urgent need to develop novel treatment strategies using currently available resources. An adjunctive, host-directed therapy (HDT) designed to act on the host, instead of the bacteria, by boosting the host immune response through activation of intracellular pathways could be the answer. The integration of multidisciplinary approaches of repurposing currently FDA-approved drugs, with a targeted drug-delivery platform is a very promising option to reduce the long timeline associated with the approval of new drugs - time that cannot be afforded given the current levels of morbidity and mortality associated with TB infection. The deficiency of vitamin A has been reported to be highly associated with the increased susceptibility of TB. All trans retinoic acid (ATRA), the active metabolite of vitamin A, has proven to be very efficacious against TB both in vitro and in vivo. In this review, we discuss and summarise the importance of vitamin A metabolites in the fight against TB and what is known regarding the molecular mechanisms of ATRA as a host-directed therapy for TB including its effect on macrophages cytokine profile and cellular pathways. Furthermore, we focus on the issues behind why previous clinical trials with vitamin A supplementation have failed, and how these issues might be overcome.

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Tuberculosis deaths and resistance are increasing – novel therapies are needed.

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Vitamin A deficiency is a strong risk factor for active tuberculosis in contacts.

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All Trans Retinoic Acid is a promising host-directed therapy for tuberculosis.

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It has pleiotropic effects on macrophages & other immune cells in vitro and in vivo.

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Inhaled rather than systemic All Trans Retinoic Acid therapy may be most effective.

Priming with Retinoic Acid, an Active Metabolite of Vitamin A, Increases Vitamin A Uptake in the Small Intestine of Neonatal Rats

Given that combined vitamin A (VA) and retinoic acid (RA) supplementation stimulated the intestinal uptake of plasma retinyl esters in neonatal rats, we administrated an RA dose as a pretreatment before VA supplementation to investigate the distinct effect of RA on intestinal VA kinetics. On postnatal days (P) 2 and 3, half of the pups received an oral dose of RA (RA group), while the remaining received canola oil as the control (CN). On P4, after receiving an oral dose of ³H-labeled VA, pups were euthanized at selected times (n = 4–6/treatment/time) and intestine was collected. In both CN and RA groups, intestinal VA mass increased dramatically after VA supplementation; however, RA-pretreated pups had relatively higher VA levels from 10 h and accumulated 30% more VA over the 30-h study. Labeled VA rapidly peaked in the intestine of CN pups and then declined from 13 h, while a continuous increase was observed in the RA group, with a second peak at 10 h and nearly twice the accumulation of ³H-labeled VA compared to CN. Our findings indicate that RA pretreatment may stimulate the influx of supplemental VA into the intestine, and the increased VA accumulation suggests a potential VA storage capacity in neonatal intestine.

The role of vitamin A and vitamin D in modulation of the immune response with a focus on innate lymphoid cells

The immune system with its numerous and complex interactions helps to protect the host from pathogenic microorganisms, and enables cleaning of damaged tissues. It is also associated with constant "monitoring" of the appearance of malignant cells and their elimination that can occur in the human body. Such a role depends on many factors including adequate intake of nutrients, including vitamins. The effect of vitamin supplementation on the modulation of the immune response has always been the focus of numerous studies. Vitamins A and D have been shown to have the greatest immune-modulatory effect. In this review, we discuss and consider the possible roles of vitamins A and D on the immune response through innate and adaptive immune cells, with special focus on the cell population recently characterized as innate lymphoid cells. Recent literature data indicate that vitamin A and its metabolites modulate the balance between Th1 and Th2 immunity. In addition, vitamin D expresses protective effects on the innate immune system and inhibitory effects on adaptive immunity.

Microbial Production of Bioactive Retinoic Acid Using Metabolically Engineered Escherichia coli

Microbial production of bioactive retinoids, including retinol and retinyl esters, has been successfully reported. Previously, there are no reports on the microbial biosynthesis of retinoic acid. Two genes (blh_SR and raldh_HS) encoding retinoic acid biosynthesis enzymes [β-carotene 15,15′-oxygenase (Blh) and retinaldehyde dehydrogenase2 (RALDH2)] were synthetically redesigned for modular expression. Co-expression of the blh_SR and raldh_HS genes on the plasmid system in an engineered β-carotene-producing Escherichia coli strain produced 0.59 ± 0.06 mg/L of retinoic acid after flask cultivation. Deletion of the ybbO gene encoding a promiscuous aldehyde reductase induced a 2.4-fold increase in retinoic acid production to 1.43 ± 0.06 mg/L. Engineering of the 5’-UTR sequence of the blh_SR and raldh_HS genes enhanced retinoic acid production to 3.46 ± 0.16 mg/L. A batch culture operated at 37 °C, pH 7.0, and 50% DO produced up to 8.20 ± 0.05 mg/L retinoic acid in a bioreactor. As the construction and culture of retinoic acid–producing bacterial strains are still at an early stage in the development, further optimization of the expression level of the retinoic acid pathway genes, protein engineering of Blh and RALDH2, and culture optimization should synergistically increase the current titer of retinoic acid in E. coli.

Nutraceuticals in Viral Infections: An Overview of the Immunomodulating Properties

Nutraceuticals, including vitamin D, vitamin A, zinc, lactoferrin, polyphenols coenzyme Q, magnesium, and selenium, are implicated in the modulation of the complex molecular pathways involved in the immune response against viral pathogens. A common element of the activity of nutraceuticals is their ability to enhance the innate immune response against pathogens by acting on the major cellular subsets and inducing the release of pro-inflammatory cytokines and antimicrobial peptides. In some cases, this action is accompanied by a direct antimicrobial effect, as evidenced in the specific case of lactoferrin. Furthermore, nutraceuticals act through complex molecular mechanisms to minimize the damage caused by the activation of the immune system against pathogens, reducing the oxidative damage, influencing the antigen presentation, enhancing the differentiation and proliferation of regulatory T cells, driving the differentiation of lymphocyte subsets, and modulating the production of pro-inflammatory cytokines. In this paper, we review the main molecular mechanisms responsible for the immunomodulatory function of nutraceuticals, focusing on the most relevant aspects for the prevention and treatment of viral infections.

Gastrointestinal cytomegalovirus disease secondary to measles in an immunocompetent infant

Yang et al reported an immunocompetent infant with gastrointestinal cytomegalovirus disease secondary to measles infection. We express our opinion about the diagnosis and treatment of this rare disease.

VitA or VitD ameliorates bronchopulmonary dysplasia by regulating the balance between M1 and M2 macrophages

PURPOSE

To investigate the therapeutic effects of vitamin A (VitA) or vitamin D (VitD) against bronchopulmonary dysplasia (BPD) and the underlying mechanism from the perspective of macrophage polarization.

METHODS

A BPD model was established on rats. Hematoxylin and eosin staining was used to evaluate the pathological state of lung tissues. The expression of CD68 was determined by immunohistochemistry assay. The infiltration of M1 and M2 macrophages was marked by immunofluorescence. The expression levels of tumor necrosis factor (TNF)-α, interleukin (IL)-10, nitric oxide synthase (NOS), and arginase-1 (Arg-1) were evaluated by quantitative reverse transcription polymerase chain reaction assay, and the ratio of M1/M2 in the bronchoalveolar lavage fluid was determined by flow cytometry.

RESULTS

Disordered alveolar structure in the lung tissue, thickened alveolar septa, and infiltration of inflammatory cells around the alveolar cavity and pulmonary septa were observed in lipopolysaccharide (LPS)-treated rats. On day 21 post-natal (PN21), the pathological state was aggravated, alveolar simplification was observed, and the expression level of CD68 in the lung tissues was significantly elevated, and these results were dramatically alleviated in the VitA, VitD, and VitA+VitD groups. However, no significant synergistic effect was observed between VitA+VitD and VitA or VitD groups. After the administration with VitA or VitD, IL-10 and Arg-1 were up-regulated on PN10. TNF-α and NOS were up-regulated on PN21. The ratio of macrophage polarization and M2 macrophages increased considerably after the stimulation with LPS, and this result was significantly reversed by VitA or VitD. A significant difference was observed on the effect of different dosages of VitA or VitD on macrophage polarization, among which moderate dosages of VitA or VitD exerted the most significant influence on macrophage polarization.

CONCLUSION

The BPD-linked pulmonary injury stimulated by LPS can be ameliorated by the introduction of VitA or VitD.

Identifying Targets for the Prevention of Childhood Undernutrition in a Resource-Limited Peri-Urban Ecuadorian Community

BACKGROUND

In middle-income countries, malnutrition concentrates in marginalized populations with a lack of effective preventive strategies.

OBJECTIVE

Identify risk factors for undernutrition in a peri-urban Ecuadorian community of children aged 12 to 59 months.

METHODS

Data from a cross-sectional survey in 2011 of children 1 to 5 years were analyzed including demographic data, medical history and examination, food frequency questionnaire (FFQ), anthropometric measurements, and blood for complete blood count, C-reactive protein, vitamin A, iron, and zinc levels. Dietary Diversity Score (DDS) was calculated from FFQ. Bivariate and multivariate analysis assessed effects on primary outcome of undernutrition by DDS, vitamin deficiencies, and demographic and nutritional data.

RESULTS

N = 67, 52.2% undernourished: 49.3% stunted, 25.4% underweight, and 3% wasted; 74.6% (n = 50) were anemic and 95.1% (n = 39) had low serum zinc. Dietary Diversity Score was universally low (mean 4.91 ± 1.36, max 12). Undernutrition was associated with lower vitamin A levels (20 306, IQR: 16605.25-23973.75 vs 23665, IQR: 19292-26474 ng/mL, P = .04); underweight was associated with less parental report of illness (43.8%, n = 7 vs 80% n = 40, P = .005) and higher white blood count (13.7, IQR: 11.95-15.8 vs 10.9, IQR: 7.8-14.23 × 10⁹/L, P = .02). In multiple regression, risk of undernutrition decreased by 4% for every $10 monthly income increase (95 CI%: 0.5%-7.4%, P = .02, n = 23); risk of underweight decreased by 0.06 for every increased DDS point (adjusted odds ratio: 0.06; 95 CI%: 0.004-0.91, P = .04, n = 23).

CONCLUSIONS

In this peri-urban limited-resource, mostly Indigenous Ecuadorian community, stunting exceeds national prevalence, lower monthly income is the strongest predictor of undernutrition, lower DDS can predict some forms of undernutrition, and vitamin deficiencies are associated with but not predictive of undernutrition.

Vitamin A Supplementation Coverage and Ocular Signs among Children Aged 6-59 Months in Aleta Chuko Woreda, Sidama Zone, Southern Ethiopia

Background

Periodic vitamin A supplementation to children is a cost-effective strategy to avert vitamin A deficiency. However, few pieces of evidence are available about the coverage of vitamin A supplementation at the community level in the study area. Therefore, the aim of this study was to assess vitamin A supplementation coverage and prevalence of ocular signs of vitamin A deficiency among children aged 6-59 months.

Methods

Community-based cross-sectional study design was conducted using a two-stage stratified random sampling method. Data were collected from mothers with children aged 6-59 months using a structured pretested questionnaire. A total of 665 children aged 6 to 59 months were examined for clinical signs and symptoms of vitamin A deficiency by trained clinical health professionals. Descriptive statistics and logistic regression were done.

Result

Vitamin A supplementation coverage in the study area was 36.2% (95% CI: 32.6-39.9). Overall, the prevalence of xerophthalmia was 2.7%. Age group 6-23 months (AOR: 2.1, 95% CI: 1.4-2.9), good maternal knowledge (AOR: 1.5, 95% CI: 1.2-2.1), children with high wealth status (AOR: 2.3, 95% CI: 1.4-3.8), precampaign health education on vitamin A (AOR: 3.4,95% CI: 2.1-5.6), member of Health Development Army (AOR: 2.7, 95% CI: 1.7-4.2), and access to health facility within <30 minutes (AOR: 2.5, 95% CI: 1.6-3.8) were significantly associated with the receipt of vitamin A capsule.

Conclusion

Vitamin A supplementation coverage of the study area was low as compared to the UNICEF threshold of 70%. Vitamin A deficiency is a public health problem in the study area. Increasing maternal level of knowledge, precampaign health education on vitamin A supplementation, and strengthening Health Development Army are recommended to increase the vitamin A supplementation coverage.

Factors associated with coverage of vitamin a supplementation among Bangladeshi children: mixed modelling approach

Background

Vitamin A deficiency (VAD) is a prominent and widespread public health problem in developing countries, including Bangladesh. About 2% of all deaths among under-five children are attributable to VAD. Evidence-based information is required to understand the influential factors to increase vitamin A supplementation (VAS) coverage and reduce VAD. We investigated the potential factors affecting VAS coverage and its significant predictors among Bangladeshi children aged 6 to 59 months using the VAS clustered data extracted from the latest Bangladesh Demographic and Health Survey 2014.

Methods

Data were analysed using mixed logistic regression (MLR) modelling approach in the generalised linear mixed model framework. The MLR model performs better than logistic regression for analysing the clustered data because of its minimum Akaike information criterion value. The likelihood ratio test showed that the variance component was significant. Therefore, the clustering effect among children was inevitable to use.

Results

VAS coverage among under-five children was 63.6%, which is not optimal and below the WHO’s recommendation and the country’s target of 90%. Children aged 25 to 36 months (AOR = 2.07, 95% CI: 1.711 to 2.513), who had higher educated mothers (AOR = 1.37, p = 0.033, 95% CI: 1.026–1.820) and fathers (AOR = 1.32, p = 0.027, 95% CI: 1.032–1.683), whose mothers had media exposure (AOR = 1.22, p = 0.006, 95% CI: 1.059–1.408) and NGO membership (AOR = 1.24, p = 0.002, 95% CI: 1.089–1.422) were more likely to consume VAS.

Conclusion

The relevant authorities should create proactive awareness programs for highly vulnerable local communities, specifically targeted to educate the children’s mothers about the necessity and benefits of childhood nutrition.

Global patterns in vision loss burden due to vitamin A deficiency from 1990 to 2017

OBJECTIVE

To investigate the vision loss burden due to vitamin A deficiency (VAD) at the global, regional and national levels by year, age, sex and socio-economic status using prevalence and years lived with disability (YLD).

DESIGN

International, retrospective, comparative burden-of-disease study.

SETTING

Prevalence and YLD data were extracted from the Global Burden of Disease (GBD) Study 2017. The association of age-standardised YLD rates and human development index (HDI) was tested by Pearson correlation and linear regression analyses. The Gini coefficient and concentration index (CI) were calculated to demonstrate the trends in between-country inequality in vision loss burden due to VAD.

PARTICIPANTS

All participants met the GBD inclusion criteria.

RESULTS

The age-standardised prevalence rate increased by 9·2 %, while the age-standardised YLD rates rose by 10·8 % from 1990 to 2017. Notably, the vision loss burden caused by VAD showed a declining trend since 2014. The vision loss burden was more concentrated in the post-neonatal age group and decreased with increasing age. The age-standardised YLD rates were inversely correlated with HDI (r = -0·2417, P = 0·0084). The CI and Gini coefficients indicated that socio-economic-related and between-country inequality declined from 2000 to 2017. VAD was the eighth leading cause of the age-standardised prevalence rate and ninth leading cause of age-standardised YLD rate among fifteen causes of vision loss in 2017.

CONCLUSION

VAD has become one of the significant leading causes of vision loss globally. Efforts to control vision impairment related to VAD are needed, especially for children in countries with lower socio-economic status.

Vitamin A supplementation and estimated number of averted child deaths in Ethiopia: 15 years in practice (2005-2019)

Vitamin A supplementation (VAS), started as a short‐term strategy pending dietary improvements, has been implemented in Ethiopia for the last 15 years. We aimed to describe the trends in VAS coverage and estimated the associated reductions in child mortality. VAS coverage data obtained from the District Health Information System and the Demographic and Health Surveys were linked to child mortality data from the United Nations Interagency Group for Child Mortality Estimation (UN IGME). The number of child deaths averted was modelled assuming 12% and 24% reductions in all‐cause mortality. From 2006 to 2011, VAS was delivered through campaigns, and coverage was above 85%. However, from 2011 onwards, VAS delivery was integrated to the routine health system, and the coverage declined to <60% with significant disparities by wealth quintile and rural–urban residence. VAS has saved between 167,563 to 376,030 child lives (2005–2019), but additional lives (>42,000) could have been saved with a universal coverage (95%). Inconsistent supply of vitamin A capsules, but more importantly, low access to health care, and the limited contact opportunities for children after 24 months may have contributed to the declining VAS coverage. Any changes in target or scale‐up should thus consider these spatial and socioeconomic variations. Increasing the coverage of VAS and closing the equity gap in access to nutrition services is critical. However, with alternative programmes like vitamin A fortification being set‐up, the benefits and safety of VAS need to be closely monitored, particularly in areas where there will be overlap.

Child Night Blindness and Bitot's Spots Are Public Health Problems in Lay Armachiho District, Central Gondar Zone, Northwest Ethiopia, 2019: A Community-Based Cross-Sectional Study

Background

Night blindness (XN) is a condition in which a person cannot see in dim light and is the earliest clinical manifestation of vitamin A deficiency. Globally, vitamin A deficiency is a public health problem in 122 countries, of which 45 countries have moderate to severe child night blindness. Therefore, this study is aimed at assessing the prevalence and associated factors of night blindness and Bitot's spot among children aged 24-59 months.

Methods

A community-based cross-sectional study was employed from February to March 2019 among children aged 24-59 months in the Lay Armachiho District, Amhara region. A structured and pretested questionnaire was used for data collection. Descriptive summary statistics were used to describe the study population. Bivariate and multivariable logistic regression models were used to identify associated factors.

Results

Out of 1007 children, 1.9% and 2.2% had night blindness and Bitot's spot, respectively. Illiterate mothers (AOR = 2.94; 95%CI = (1.12, 6.72)), age of 48 to 59 months (AOR = 9.81; 95%CI = (1.24, 77.36)), ≥4 family sizes (AOR = 4.52; 95%CI = (1.02, 19.90)), had diarrhea (AOR = 5.00; 95%CI = (1.73, 14.54)), and had a respiratory tract infection (AOR = 3.14; 95%CI = (1.02, 9.70)) were significantly associated with night blindness. Age of 48-59 months (AOR = 4.23; 95%CI = (1.13, 14.86)) and mothers who did not wash their hands after using the toilet (AOR = 3.02; 95%CI = (1.01, 9.13)) were predictor variables for Bitot's spots.

Conclusion

The prevalence of night blindness and Bitot's spots was high. Child's age, mother's educational status, family size, diarrhea in the last 2 weeks, and respiratory tract infection in the last 2 weeks were predictive variables for night blindness. Besides, handwashing practice after using the toilet and child's age were significantly associated with Bitot's spot among children. Therefore, both night blindness and Bitot's spots are a public health problem and call for the attention of health professionals in primary health care facilities.

Clinical Dry Eye and Meibomian Gland Features Among Dry Eye Patients in Rural and Urban Ghana

Aim

To compare differences in clinical dry eye features and meibomian gland health status between dry eye patients from rural and urban populations in Ghana.

Methods

We examined 211 (rural=109, urban=102) participants with subjective dry eye symptoms. Tear film break -up time (TBUT), Schirmer’s test and ocular surface staining (OSS) were assessed. Symptoms were evaluated using the SPEED II questionnaire. Meibomian glands (MG) in the right eye upper (UL) and lower lids (LL) were imaged using a custom meibographer. MG area was determined by intensity threshold segmentation using Image J software. MG loss (MGL) was also graded based on Pult’s grading scheme. Mann–Whitney, Spearman correlation, chi-square and odds analyses were performed; p<0.05 was considered significant.

Results

Rural participants showed greater SPEED scores, reduced TBUT, and lower Schirmer scores, p <0.05. The proportion of rural participants with MGL were significantly more (82.3%) than urban participants (63.3%), p <0.05. They also showed greater MGL than urban participants, p <0.05. Chi-square test revealed significantly different meiboscale distributions (UL: χ²=13.58, LL: χ²=15.29) between the groups, p <0.05. Overall significant relationships were observed between MGL and age [r_s= 0.61], OSS [r_s= 0.35], TBUT [r_s= −0.52], and Schirmer scores [r_s= −0.40], p <0.05.

Conclusion

The data suggest that the participants from the rural population have worse dry eye and meibomian gland health status than those from the urban population. The significant relationships between the various clinical variables suggest important links between MGD and DED. Subtle differences in the everyday working and living environment could likely account for the differences in the severity of DED and MGD between the two groups. And considering the increased pattern of urbanization, industrialization and modernization and the related environmental effects in Africa, future longitudinal studies on specific environmental risk factors or mediators of DED and MGD are necessary to ascertain the MGD and DED situation in Ghana and Africa at large.

Effect of vitamin A on intestinal mucosal injury in pediatric patients receiving hematopoietic stem cell transplantation and chemotherapy: a quasai-randomized trial

Objective

Vitamin A is involved in maintenance of gut mucosal integrity and normal immune function. However, it is unclear whether these functions of vitamin A have any beneficial effects in patients undergoing hematopoietic stem cell transplantation (HSCT). In this study, we aimed to examine the potential protective effect of vitamin A supplementation on gastrointestinal (GI) mucosal integrity in HSCT recipients using plasma citrulline as a surrogate marker of intestinal integrity.

Results

We performed a quasi-randomized trial in 30 pediatric patients undergoing HSCT. Half (n = 15) of the patients received a single high dose of vitamin A (200,000 IU) before the conditioning regimen was given, and half (n = 15) did not. Clinical data of patients who developed post-transplant complications were recorded for 60 days after HSCT. There were no significant differences in mean plasma citrulline levels on day 7 after HSCT between the treatment and control groups (5.8 vs. 5.9 µmol/L, respectively). The incidence of mucositis and other complications were not different between the two groups within 60 days of HSCT. Vitamin A supplementation prior to HSCT in pediatric patients had no clinical benefit in protecting GI mucosal integrity.

Uptake of routine vitamin A supplementation for children in Humbo district, southern Ethiopia: community-based cross-sectional study

Background

In low- and middle-income countries routine vitamin A supplementation (VAS) is a key strategy for reducing vitamin A deficiency and mortality and morbidity of preschool children. However, in Ethiopia, there is paucity of evidence regarding the level and determinants of the uptake of the supplement. This study was designed to assess the coverage and predictors of VAS among preschool children in Humbo district, Southern Ethiopia.

Methods

A cross-sectional study was conducted in April 2016. A total of 840 mothers/caregivers having children 6–59 months of age were selected using multistage cluster sampling technique from six rural villages implementing routine VAS program. Data were collected using interviewer administered questionnaire. Possible predictors considered in the study include distance from the nearby health facility, household socio-economic status, type of the household (model vs non-model), maternal access to health education on VAS, and knowledge on vitamin A and VAS. Multivariable logistic regression analysis was performed to identify predictors of uptake of VAS. The outputs are presented using adjusted odds ratio (AOR) with the respective 95% confidence interval (CI).

Results

The coverage of VAS was 75.0% (95% CI: 72.1–77.9). Better knowledge of mothers about the importance of the supplement (AOR: 1.49, 1.02–2.17), obtaining VAS related information from frontline community health workers (AOR: 1.51, 1.34–2.72) than health professionals and being from households in the “rich” wealth tertile (AOR: 1.80, 95% CI: 1.07–3.03) were positively associated with uptake VAS.

Conclusion

The VAS coverage of the area was approaching the expected national target of 80%. However, the uptake can be enhanced though awareness creation and improving socio-economic status of the community.

The efficacy of a compounded micronutrient supplement on the incidence, duration, and severity of the common cold: A pilot randomized, double-blinded, placebo-controlled trial

Purpose

Viral upper respiratory infections are associated with significant health and economic impact. This study sought to determine the efficacy of routine immune system micronutrient supplementation on the incidence, duration and severity of common cold symptoms.

Methods

This pilot study was a randomized, double-blinded, placebo-controlled trial of N = 259 with asymptomatic participants aged 18 to 65 in two cold seasons of 2016 and 2017. The treatment group received an immune system targeted micronutrient caplet, while the placebo group received a micronized cellulose caplet externally identical to the treatment caplet. Weekly surveys were sent electronically to participants to document common cold incidence, duration and severity. Primary statistical results were obtained using mixed-effects logistic regressions to account for longitudinal measurements for participants.

Results

The odds of acquiring an upper respiratory infection, adjusted for potential confounders, was estimated to be 0.74 times lower in the treatment group (p = 0.14). The odds of reporting specific symptoms were statistically lower in the treatment arm compared to the placebo arm for runny nose (OR = 0.53, p = 0.01) and cough (OR = 0.51, p = 0.04). Shorter durations of runny nose and cough were also observed in the treatment arm compared to placebo (both p < 0.05). There was no significant difference in severity of symptoms in either group. The observed proportion of reported cold symptoms in the treatment group was lower compared to the placebo group between late January and February in two consecutive cold seasons. Given the physical, workplace and economic impact of upper respiratory infections, this low cost and low risk intervention should be further studied with more robust investigation and meticulous experimental design.

Emerging Cancer Epigenetic Mechanisms Regulated by All-Trans Retinoic Acid

All-trans retinoic acid (RA), which is the dietary bioactive derivative obtained from animal (retinol) and plant sources (beta-carotene), is a physiological lipid signal of both embryonic and postembryonic development. During pregnancy, either RA deficiency or an excessive RA intake is teratogenic. Too low or too high RA affects not only prenatal, but also postnatal, developmental processes such as myelopoiesis and mammary gland morphogenesis. In this review, we mostly focus on emerging RA-regulated epigenetic mechanisms involving RA receptor alpha (RARA) and Annexin A8 (ANXA8), which is a member of the Annexin family, as well as ANXA8 regulatory microRNAs (miRNAs). The first cancer showing ANXA8 upregulation was reported in acute promyelocytic leukemia (APL), which induces the differentiation arrest of promyelocytes due to defective RA signaling caused by RARA fusion genes as the PML-RARA gene. Over the years, ANXA8 has also been found to be upregulated in other cancers, even in the absence of RARA fusion genes. Mechanistic studies on human mammary cells and mammary glands of mice showed that ANXA8 upregulation is caused by genetic mutations affecting RARA functions. Although not all of the underlying mechanisms of ANXA8 upregulation have been elucidated, the interdependence of RA-RARA and ANXA8 seems to play a relevant role in some normal and tumorigenic settings.