Serum Retinol Research Articles

Serum retinol, alpha-tocopherol, cholecalciferol, and some mineral levels in ruminants with congenital digestive and urogenital system anomalies

Serum retinol, alpha-tocopherol, cholecalciferol, and some mineral levels in ruminants with congenital digestive and urogenital system anomalies

Assessment of some selected micronutrients among women of reproductive age within urban and rural settings in Kano State

Women of reproductive age (WRA) are prone to unbalance micronutrient status due to changes associated with normal physiological conditions such as menstruation, pregnancy and lactation. This study was done to assess some selected micronutrients among women of reproductive age within urban and rural settings in Kano state, Nigeria. A community-based cross-sectional study was conducted among 192 WRA (15-49 years) in 4 randomly selected LGAs in urban and rural settings each. Samples of blood and urine were collected to determine the levels of iron, iodine, vitamin A, folate and zinc using ELISA kit. Hemoglobin concentration was also determined using an automated analyzer. From the result obtained in the present study, serum retinol was found to be significantly different (p=0.008) whereas hemoglobin concentration (p=0.200), serum ferritin (p=0.226), urine iodine (p=0.141), serum folate (p=0.924) and serum zinc (p=0.410) had no significant difference between urban and rural participants. Iron deficiency anaemia (13.5%), iodine (29.2%) and zinc (33.3%) deficiencies have higher incidences in the urban areas whereas anaemia (26.0%), iron (46.9%), Vitamin A (34.4%) and folate (46.9%) deficiencies were higher in the rural areas. Our data suggest the need for public health sensitization and enlightenment such as dietary diversity, micronutrient fortification, and supplementation to lower the likelihood of widespread micronutrient deficiencies.

Gestational Age Is Positively Associated with Retinol and α-Tocopherol in Preterm Infants: The Mediating Role of Birth Weight

Oxidative stress is thought to be one of the common mechanisms for several neonatal diseases in premature infants. Moreover, fat-soluble antioxidant vitamins, i.e., retinol and α-tocopherol, have been found to be low in preterm neonates; however, data are limited. The aim of this was to assess the circulating α-tocopherol and retinol concentrations in preterm infants at birth and investigate if they are related to gestational age. Retinol and α-tocopherol were measured on the first day after birth in 30 preterm neonates with HPLC. Means ± SD of serum retinol and α-tocopherol were 392.0 ± 162.9 μg/L and 6.83 ± 3.02 mg/L, respectively. In total, 73% of infants had a very low birth weight (<1500 g) and 23.3% were small for gestational age (SGA). Moreover, 10% of neonates had a retinol deficiency and 20% had an α-tocopherol deficiency. The retinol concentration was lower in SGA infants compared to appropriate for gestational age ones (340.85 ± 75.89 vs. 407.60 ± 179.83 μg/L, correspondingly p = 0.030). Retinol was linearly related to gestational age (Pearson’s rho = 0.84, p < 0.001) but the association did not remain significant after an adjustment for birth weight (partial rho = 0.193, p = 0.316). α-tocopherol was nonlinearly associated with gestational age (Spearman’s rho = 0.470, p = 0.044). The assessment of the vitamin status and potential deficiency in neonates is crucial in order to appropriately support the nutritional needs of newborns.

Retrospective Observational Analysis of Free Serum Retinol in a Cohort of Pediatric Patients with Short Bowel Syndrome and Intestinal Failure

Retrospective Observational Analysis of Free Serum Retinol in a Cohort of Pediatric Patients with Short Bowel Syndrome and Intestinal Failure

Effects of sources and routes of administration of vitamins A, D and copper on postnatal status of these micronutrients in piglets.

Twenty-six nulliparous sows were fed conventional gestation and lactation diets supplemented (N = 13) or not (N = 13) with extra daily supplements of 25-hydroxy-cholecalciferol (25-OH-D3; 4 ĸIU), β-carotene (24 ĸIU), and copper (Cu)-proteinate (45 mg) from day 90 of gestation to 21 d of lactation (L21). In each litter, 10 piglets were divided into 5 pairs received, at 2 (L2) and 8 d (L8) of age, one of the five combinations of micronutrient sources and routes of administration (N = 260 piglets total). These neonatal treatments (N = 26 pairs or 52 piglets each) consisted of oral vitamin D3, retinol acetate and CuSO4 (T1); oral 25-OH-D3, β-carotene, and Cu proteinate (T2); exposure to ultraviolet light (UVB), oral retinol palmitate and Cu gluconate (T3); intramuscular vitamin D3 and retinyl propionate and oral Cu acetate (T4); oral saline (CTRL). Oral or intramuscular provisions corresponded to 12 mg of Cu and 70 and 12 ĸIU of vitamins A and D, respectively. Blood samples were collected from all piglets at L2, L8, and L21 for determination of serum Cu, retinol, and 25-OH-D3. Body weight was measured at birth, L2, L8, and L21. Piglets were weaned at L21, and liver and blood samples were collected 2 d later to evaluate oxidative enzymes in blood and liver and hepatic ATP concentrations and expression of genes associated with antioxidant status. Sow treatments had marginal or no impacts on Cu, retinol, 25-OH-D3, or antioxidant status in piglet blood serum and liver. However, when supplements were given to piglets, hepatic Cu was 38% greater in for all treated piglets compared to CTRL (P < 0.01), hepatic retinol was 3 times higher in T1 than in CTRL (P < 0.01) and intermediate for other treatments whereas serum 25-OH-D3 was markedly increased with T2 and T3 at L8 and L21, respectively, compared to CTRL (Piglet treatment × Age interaction, P < 0.01). Concerning antioxidant activities, glutathione peroxidase, and superoxide dismutase were increased (P < 0.03) in plasma of T2 piglets whereas the highest values (P < 0.03) for indicators of oxidative damage to proteins were observed in T4 piglets. The study revealed that oral Cu proteinate from T2, oral retinol acetate from T1, oral 25-hydroxy-cholecalciferol from T2, and UVB light exposure from T3 were the most efficient ways of increasing the postnatal status of these micronutrients in suckling piglets and this may have some impacts on their peri-weaning antioxidant status.

Exploratory 5-year follow-up study of retinol, tocopherols, and carotenoids in multiple sclerosis

BackgroundRetinol, tocopherols, and carotenoids (RTC) have physiological roles as vitamins, pro-vitamins, and antioxidants, and provide biomarkers of dietary vegetable and fruit intake. The goal was to investigate RTC in multiple sclerosis (MS). MethodsThis exploratory study included 106 people with MS (71 relapsing-remitting MS or RR-MS; and 35 progressive MS or PMS) and 31 healthy controls (HC) at baseline and 5-year follow-up (5YFU). Serum retinol, α-carotene, β-carotene, α-tocopherol, δ-tocopherol, γ-tocopherol, β-cryptoxanthin, lutein/zeaxanthin, and lycopene were measured using high performance liquid chromatography. Serum neurofilament light chain (sNfL) levels were measured using the single molecule array method. Expanded Disability Status Scale (EDSS) and low contrast letter acuity (LCLA) were used as disability measures. ResultsRetinol in MS was positively correlated with α-carotene, β-carotene, β-cryptoxanthin, lutein/zeaxanthin, and α-tocopherol but negatively correlated with δ-tocopherol. EDSS was associated with α-tocopherol, δ-tocopherol, and lycopene. Greater retinol levels were associated with greater LCLA in RR-MS and PMS; high contrast visual acuity was not associated. Greater γ-tocopherol levels were associated with lower LCLA and high contrast visual acuity in PMS. ConclusionsRTC exhibit distinctive associations with LCLA and EDSS in MS.

Assessment of vitamin A levels in breast milk and serum of lactating mothers in Southeast Nigeria

Background: Vitamin A (VA) is an essential micronutrient critical to human health, infants rely on their mother’s breast milk for sufficient supply. This makes the maternal diet a crucial source of VA for infant growth and development. Aims: This study aimed to assess maternal VA status by assessing serum and breast milk retinol concentrations as well as dietary intake in nursing mothers. Subjects and Methods: A clinic-based cross-sectional study, conducted in Awka, south-east Nigeria, was used to assess 127 lactating women at one to 24 months post-partum. Blood and breast milk samples were obtained from each participant in a fasted state while dietary intake was assessed via an interviewer-administered semi-structured food frequency questionnaire. Retinol concentration was analyzed by spectrophotometry. Descriptive statistics were used to summarize the data while Spearman rank correlation analysis was used to determine associations between breast milk and serum retinol concentrations and study variables. Results: The mean retinol concentration in the serum of the women was a borderline value of 0.75 ± 0.64 µmol/L while the mean retinol concentration in breast milk was 0.99 ± 0.71 µmol/L. Further, the mean milk fat content was 56.18 ± 32.32 g/L while the mean milk retinol to fat ratio was 0.027 ± 0.044 µmol/g. Maternal diet consisted of a preference for provitamin A foods with low bioavailability. The mean retinol concentration in breast milk increased with time post-partum. There was no statistically significant relationship found between the frequency of consumption of most foods and the concentration of retinol in breast milk. Conclusion: The evidence of VA deficiency highlights the need for screening and nutrition education of breastfeeding mothers during ante- and post-natal visits. Keywords: Human milk, serum, vitamin A, maternal diet.

RETRACTED: Analysis of the association between serum levels of 25(OH)D, retinol binding protein, and Cyclooxygenase-2 and the disease severity in patients with diabetic foot ulcers.

Diabetic foot ulcers (DFUs) pose significant clinical challenges, representing severe complications in diabetes mellitus patients and contributing to non-traumatic amputations. Identifying reliable biomarkers can optimize early diagnosis and improve therapeutic outcomes. This study focused on evaluating the association between serum levels of 25-hydroxyvitamin D [25-(OH)D], Serum Retinol Binding Protein (RBP), and Cyclooxygenase-2 (COX-2) in elderly DFU patients. A retrospective study involving 240 participants, from March 2020 to March 2023. The participants were segmented into three cohorts: 80 with DFUs, 80 diabetic patients without DFUs, and 80 healthy controls. Serum concentrations of the three biomarkers were assayed using methods like enzyme-linked immunosorbent assay (ELISA), chemiluminescence immunoassay, and an automated biochemistry analyser. Comparisons were made both between groups and within the DFU group based on disease severity. Statistical analysis revealed significant differences in biomarker levels across the groups (p < 0.05). COX-2 and RBP concentrations were highest in the DFU group, followed by the non-DFU diabetic group, and lowest in the control group. Conversely, 25(OH)D levels were highest in the control group, followed by the non-DFU diabetic group, and lowest in the DFU group. Within the DFU group, RBP and COX-2 levels increased with disease severity, while 25(OH)D levels decreased. These variations were especially pronounced in patients with the most severe Wagner grading. A significant positive correlation was observed between disease severity and levels of RBP (r = 0.651, p < 0.05) and COX-2 (r = 0.356, p < 0.05). Conversely, a significant negative correlation was identified between disease severity and 25(OH)D levels (r = -0.658, p < 0.05). Assessing 25(OH)D, RBP, and COX-2 serum levels offers a promising tool for evaluating the severity and progression of DFUs. Monitoring these biomarkers can enrich our understanding of the metabolic and inflammatory pathways of the disease and potentially refine therapeutic strategies.

Vitamin A - a scoping review for Nordic nutrition Recommendations 2023.

Vitamin A refers to a group of fat-soluble compounds with retinol activity, including all-trans retinol and pro-vitamin A carotenoids. Bioactive compounds include retinal and all-trans retinoic acid with important functions in vision, immune function, growth, and development. The literature search that was performed for the current scoping review yielded a total of seven publications relevant to setting the recommended daily intake for vitamin A. In total, six publications assessed the relationship of serum retinol and/or dietary vitamin A intake with fracture risk (n = 2), cancer (n = 3), and deficiency after bariatric surgery (n = 1). One additional report by the European Food Safety Administration (EFSA) with updated average requirements was included. The outcomes-based systematic reviews and meta-analyses showed positive associations for vitamin A intake and serum retinol with risk of hip fracture. Weak or inconclusive associations were observed for cancer or obesity. One publication by EFSA with updated estimated average requirements and population reference intakes for dietary vitamin A intakes was published in 2015. The EFSA recommendations and estimated average requirements are based on a European reference population, with body weights derived from an assumed body mass index of 22, which might be too low and not representative of the Nordic and Baltic populations, and consequently resulting in lower estimated average requirements and recommendations. In conclusion, there were limited new outcomes-based data for vitamin A and health outcomes.

Heat Stress Impairs Male Reproductive System with Potential Disruption of Retinol Metabolism and Microbial Balance in the Testis of Mice

BackgroundHeat stress (HS) has a harmful impact on the male reproductive system, primarily by reducing the sperm quality. The testicular microenvironment plays an important role in sperm quality. ObjectivesThis study aimed to explore the underlying mechanism by which HS impairs the male reproductive system through the testicular microenvironment. MethodsTen-week-old male mice (n = 8 mice/group) were maintained at a normal temperature (25°C, control) or subjected to HS (38°C for 2 h each day, HS) for 2 wk. The epididymides and testes were collected at week 2 to determine sperm quality, histopathology, retinol concentration, the expression of retinol metabolism-related genes, and the testicular microbiome. The testicular microbiome profiles were analyzed using biostatistics and bioinformatics; other data were analyzed using a 2-sided Student’s t test. ResultsCompared with the control, HS reduced (P < 0.05) sperm count (42.4%) and motility (97.7%) and disrupted the integrity of the blood–testis barrier. Testicular microbial profiling analysis revealed that HS increased the abundance of the genera Asticcacaulis, Enhydrobacter, and Stenotrophomonas (P < 0.05) and decreased the abundance of the genera Enterococcus and Pleomorphomonas (P < 0.05). Notably, the abundance of Asticcacaulis spp. showed a significant negative correlation with sperm count (P < 0.001) and sperm motility (P < 0.001). Moreover, Asticcacaulis spp. correlated significantly with most blood differential metabolites, particularly retinol (P < 0.05). Compared with the control, HS increased serum retinol concentrations (25.3%) but decreased the testis retinol concentration by 23.7%. Meanwhile, HS downregulated (P < 0.05) the expression of 2 genes (STRA6 and RDH10) and a protein (RDH10) involved in retinol metabolism by 27.3%–36.6% in the testis compared with the control. ConclusionsHS reduced sperm quality, mainly because of an imbalance in the testicular microenvironment potentially caused by an increase in Asticcacaulis spp. and disturbed retinol metabolism. These findings may offer new strategies for improving male reproductive capacity under HS.

Retinol Levels and Severity of Patients with COVID-19.

The new coronavirus infection represents a serious threat to global health and economies. In this sense, it is paramount to know the nutritional factors that may be related to the prognosis of the disease. Evidence shows that vitamin A may play an important preventive and therapeutic role in supporting respiratory infections as in COVID-19. The aim of our study was to evaluate the association of vitamin A (retinol) status with the prognosis of the disease. A case-control study from a cohort study was conducted in Brazil between May and October 2020. The study population was chosen by convenience, consisting of participants diagnosed with COVID-19. Recruitment was carried out using different approaches, including through dissemination on social media and in four hospitals in the city of Natal/RN, Brazil, recruiting participants from the COVID-19 ward and hospitalized participants who tested positive for the disease. The participants were allocated into two groups according to severity, with a group of mild (n = 88) or critical (n = 106) patients and compared to a control group (selected before the pandemic, n = 46). The extraction of retinol serum was performed and analyzed using the high-performance liquid chromatography method (HPLC). The retinol level was calculated in mmol/L, and levels below 0.7 μmol/L (20 µg/dL) were considered to be a vitamin A deficiency. Our findings suggest that the participants with mild and critical COVID-19 had lower retinol levels compared to the healthy controls (p = 0.03). In addition, milder cases of COVID-19 were associated with increased symptoms and prolonged symptoms after 90 days since the beginning of infection. However, the survival analysis showed no association with higher cases of death among participants with vitamin A deficiency (p = 0.509). More studies are needed to understand how nutritional status, including vitamin A levels, can influence prognosis and is a risk factor for the development of long COVID syndrome.

Gestational Serum Retinol Deficiency Is Associated with Enamel Hypoplasia

Enamel hypoplasia (EH) is a prevalent developmental defect of teeth that can result from various insults, including prenatal nutrient deficiencies. This study aimed to evaluate the association between prenatal serum retinol deficiency and EH in the deciduous teeth of offspring at 2-y of age. A cohort of 1,450 pregnant women was enrolled, and their prenatal nutritional status was assessed between 12 and 14 wk of gestation. Maternal serum retinol, serum 25-hydroxyvitamin D (25OHD), hemoglobin, body mass index, and birth outcomes, infant feeding practices, family socioeconomic status, and demographic information were recorded. Oral health examinations were conducted for the children semiannually, and EH was diagnosed using the Modified DDE index on all the surfaces of erupted teeth. A modified Poisson regression analysis was used to assess the cumulative risk of EH over a period of 2-y. A total of 920 (63.4%) mother–child pairs completed the study, and the cumulative EH prevalence among offspring after 2-y of follow-up was 16.5% (N = 152; 87/1,114 children in the first year and 132/920 in the second year, with 20/920 having EH only in the first year). After adjusting for potential confounders, maternal serum retinol deficiency significantly increased the risk of deciduous EH (risk ratio [RR], 2.0; 95% confidence interval [CI], 1.1–3.7). In addition, deficient serum 25OHD (RR, 6.5; 95% CI, 4.0–10.7), caesarean delivery (RR, 1.6; 95% CI, 1.0–2.4), Muslim (RR, 2.9; 95% CI, 2.0–4.1) and Christian (RR, 2.4; 95% CI, 1.6–3.5) versus Hindu religions, and very preterm birth (RR, 1.7; 95% CI, 1.1–2.9) increased the risk of EH. Children presenting with EH had 2 or more teeth affected, and the maxillary incisors were the most frequently affected, followed by the first primary molars and canines. In conclusion, maternal serum retinol deficiency during the 12 to 14 wk of gestation may increase the risk of deciduous EH, besides the well-established 25OHD deficiency.

Characteristics of Vitamin A Deficiency Retinopathy at a Tertiary Referral Center in the United States

To explore the risk factors and fundus imaging features of vitamin A deficiency retinopathy (VADR) in an academic tertiary referral center in Atlanta, GA, United States, and to propose guidance regarding diagnostic workup and management of affected patients. Single-center retrospective case series. Nine patients seen between 2015 and 2021 at the Emory Eye Center diagnosed with VADR. Retrospective chart review. Baseline serum retinol level, Snellen visual acuity, multimodal fundus imaging findings, and electroretinography findings. Nine patients, 4 (44.4%) female, with a median (range) age of 68 (50-75) years were identified. The most common underlying etiologies for vitamin A deficiency included history of gastrointestinal surgery (55.6%), liver disease (44.4%), and nutritional depletion due to low-quality diet (44.4%). Only 1 (11.1%) patient had a history of bariatric surgery. Four (44.4%) patients were on some form of vitamin A supplementation before the diagnosis of VADR. Median (range) serum retinol level was 0.06 (< 0.06-0.19) mg/L. All patients had macular subretinal hyperreflective deposits resembling subretinal drusenoid deposits, although in some cases, these were scant and sparsely distributed. Six eyes of 3 patients with longstanding deficiency had defects in the external limiting membrane (ELM). Three of these eyes additionally had macular areas of complete retinal pigment epithelium and outer retinal atrophy (cRORA). Full-field electroretinography demonstrated severe rod dysfunction and mild to moderate cone system dysfunction. Many findings of VADR were reversible with vitamin A repletion. However, all eyes with ELM defects or cRORA had persistence or continued growth of these lesions. Vitamin A deficiency retinopathy is uncommon in the developed world. However, given that early intervention can lead to dramatic visual improvement and avoid potentially permanent retinal damage, retina specialists should be familiar with its clinical presentation. The presence of nyctalopia and subretinal hyperreflective deposits in a patient with a history of gastrointestinal surgery, liver disease, and/or poor diet can be suggestive of this diagnosis, even in the presence of ongoing vitamin A supplementation. Vitamin A supplementation can vary in route and dosage and can be tailored to the individual with serial testing of serum retinol. The authors have no proprietary or commercial interest in any materials discussed in this article.

Impact of modifiable lifestyle risk factors for prostate cancer prevention: a review of the literature.

Although prostate cancer (PCa) is one of the most common cancers among men, the impact of modifiable risk and protective factors is still being debated. This review aims to qualitatively summarize the most recent studies related to potential healthy lifestyle factors affecting the development of PCa. The literature focusing on modifiable risk factors for prostate cancer was reviewed. Medline and Embase via the Ovid database were searched, and all relevant and inherent articles were analyzed. Non-eligible publications, such as review articles, editorials, comments, guidelines, or case reports, were excluded. This review confirms that there is strong evidence that being overweight or obese increases the risk of advanced prostate cancer (assessed by body mass index (BMI), waist circumference, and waist-hip ratio), particularly considering central adiposity and ethnicity as contributing factors. The possible contribution of smoking still seems not entirely clear, while alcohol seems to affect PCa prevention in patients taking 5α-reductase inhibitors (5-ARIs). Dietary fibers may have anti-inflammatory properties and improve insulin sensitivity by reducing IGF bioactivity. In particular, dietary fiber intake like insoluble and legume fibers may be inversely associated with prostate cancer risk. Also, hyperglycemia and hyperinsulinemia, with untreated diabetic fasting blood glucose levels, could be modifiable prostate cancer risk factors. In two studies, aspirin was associated with a lower risk of lethal PCa and overall mortality. Concerning the role of vitamins, despite conflicting and divergent results, serum retinol concentration seems to be associated with an increased risk of prostate cancer and high-grade prostate cancer. Some studies resulted in disagreement about the role of selenium and vitamin E. We found inconsistent and controversial findings about the association between vitamin D and prostate cancer risk. Far from being conclusive evidence, our findings confirm some strong evidence already found in the previous literature and highlight the need to clarify the role of some risk factors whose role is not yet completely known. This effort would facilitate the cultural and social change that may allow the shift from the treatment of prostate cancer when diagnosed to the real efforts needed for systematic prevention.

Home Gardening of Yellow Cassava and Orange Maize for the Prevention of Nutritional Blindness in Children: An Economic Evaluation and Value of Information Analysis

ObjectivesVitamin A deficiency is the leading cause of childhood blindness worldwide, affecting mostly Sub-Saharan Africa. We aimed to predict the cost-effectiveness of home gardening (HG) of yellow cassava and orange maize to prevent nutritional blindness in children below 5 years and to assess the likely value of obtaining additional information in reducing uncertainty surrounding its cost-effectiveness. MethodsWe developed a Markov model and carried out probabilistic sensitivity analysis with a value of information analysis. We costed resources from a societal perspective and outcomes were measured in disability-adjusted life years (DALYs). ResultsHG was estimated to cost an additional Intl$395.00 per DALY averted, with a 72.27% likelihood of being cost-effective at a threshold of Intl$2800 per DALY. The expected value of information was estimated to be Intl$29 843.50 for 1 child or Intl$925 billion for 31 million Nigerian children affected by the decision. Further research is only worthwhile for 1 parameter (relative risk of low serum retinol; expected value of perfect parameter information Intl$29 854.53 per child and Intl$925 billion for 31 million children). ConclusionHG of yellow cassava and orange maize is expected to be highly cost-effective in preventing nutritional blindness in Nigerian children. Worthwhile further research includes a cost analysis of the intervention and a high-quality randomized trial to assess the effectiveness of HG on serum retinol levels in young children.

Predictive value of serum retinol binding protein in severity and complications of acute pancreatitis: a retrospective cohort study

Objectives Retinol binding protein (RBP) is associated with an increased risk of insulin resistance, metabolic syndrome, atherosclerosis and hypertension. This study aimed to evaluate serum RBP levels in patients with acute pancreatitis (AP). Methods The study included 1,871 AP patients, including 1,411 with mild AP (MAP), 244 with moderately severe AP (MSAP), and 186 with severe AP (SAP). Retrospective analysis was conducted on RBP concentrations and other clinical data of AP patients. Results AP patients were subgrouped by RBP level into low RBP (LRBP), normal RBP (NRBP), and high RBP (HRBP) groups. The LRBP group showed a significantly higher proportion of SAP patients than NRBP and HRBP groups. Additionally, the LRBP group had the highest BISAP and CTSI scores among the three groups; WBC and CRP levels in the NRBP group were significantly lower than those in the LRBP and HRBP groups. RBP was better at predicting acute necrotic collection (ANC) than other local complications, with an area under the curve (AUC) of 0.821. RBP was also an independent risk factor for acute lung injury (ALI) and ANC in AP patients. The AUC of RBP for predicting ALI was 0.829, with 30.45 mg/L as the optimal cutoff value, and the sensitivity and specificity were 59.70% and 96.50%, respectively. The AUC of RBP for predicting ANC was 0.821, with 28.35 mg/L as the optimal cutoff value, and the sensitivity and specificity were 61.20% and 95.50%, respectively. Conclusions Serum RBP had predictive value for AP severity, local and systemic complications.

Dietary intake of preformed vitamin A and provitamin A carotenoids are not associated with serum retinol and carotenoid concentrations among children 36-59months of age in rural Burkina Faso: a cross-sectional study.

This study aimed to assess the association between dietary intake of preformed vitamin A (VA) and pro-VA carotenoids and serum retinol and carotenoid concentrations among 36-59-month-old children in a rural area in Burkina Faso. Two community-based cross-sectional studies were conducted in a rural area of Burkina Faso and included 115 children aged 36-59months. Dietary intake of preformed VA and pro-VA was assessed directly by 24-h dietary recall. Serum retinol and carotenoid (α- and β-carotene, and β-cryptoxanthin) concentrations were measured. The associations between serum retinol and carotenoid concentrations and their respective dietary intake were assessed by multiple linear regression. Geometric mean [95% CI] adjusted serum retinol concentration in children was 0.86 [0.81; 0.92] µmol/L. The prevalence of low adjusted serum retinol concentration (< 0.7µmol/L) was 26.8%. Geometric mean [95% CI] serum carotenoid concentrations were: α-carotene (0.03 [0.02; 0.03] µmol/L), β-carotene (0.14 [0.12; 0.16] µmol/L), and β-cryptoxanthin (0.17 [0.15; 0.21] µmol/L). Dietary intakes of α- and β-carotene and adjusted serum retinol and α-carotene concentrations were significantly higher during the rainy season. In multiple linear regressions, no associations were found between dietary intakes of preformed VA and pro-VA carotenoids and serum retinol and carotenoid concentrations in children aged 36-59months in Burkina Faso. There was no effect of season on the associations between preformed VA and pro-VA carotenoids intake and serum retinol and carotenoid concentrations. This study shows that dietary intakes of preformed VA and pro-VA carotenoids based on 24-h dietary recall method cannot be used as proxy of serum retinol and carotenoid concentrations in this population. The study was registered retrospectively (22 March 2018) as a clinical trial with the Pan African Clinical Trials Registry (Cochrane South Africa; PACTR201803002999356).

Autism Spectrum Disorder is Related to Increasing Intestinal Prevotella That Can Be Regulated by Vitamin A

Background: Increasing studies suggest that the microbiome-gut-brain axis plays a fundamental role in developing autism spectrum disorder (ASD). Objectives: We aimed to explore biomarkers from gut bacteria in ASD and the dietary vitamin A (VitA) relationship with intestinal bacteria of autistic children and provide a theoretical basis for dietary regulation of ASD. Methods: Ten autistic children aged 2 to 6 from special training facilities were enrolled from 2017 to 2018. At the same time, 10 healthy children aged 2 to 6 from a kindergarten were collected as a control. All participants were from Chongqing, China. The 16sRNA amplicon sequencing was used to analyze children's intestinal bacteria. The serum retinol level was detected by high-performance liquid chromatography (HPLC), and children's dietary intake was analyzed using three-day 24-hour dietary recalls. Results: There were significant differences in alpha diversity between the groups. Also, a higher relative abundance of Prevotellaceae, Prevotella 9, and Roseburia was observed among ASD children. We also found decreases in 9 bacteria (Enterobacteriales, Gammaproteobacteria, Enterobacteriaceae, Clostridiaceae 1, Clostridium sensu stricto 1, Escherichia-Shigella, Bacteroides fragilis, Escherichia coli, and Clostridium neonatale). Dietary VitA intake and serum retinol concentration were lower in the ASD group than in the control group. Meanwhile, serum VitA had a significantly negative correlation with the abundance of intestinal Prevotella 9. Conclusions: Our study helps identify some bacterial biomarkers for ASD, as in previous reports. Meanwhile, the study suggests that dietary VitA may be involved in the clinical symptoms of ASD by regulating the intestinal bacteria Prevotella. It may provide a new way to treat ASD in the future. Further studies are needed to identify the results by expanding the sample size and developing animal experiments.

P01-005-23 Comparison of Serum Retinol and the Modified Relative Dose Response Test for Vitamin A Deficiency in Women of Reproductive Age in Nigeria

P01-005-23 Comparison of Serum Retinol and the Modified Relative Dose Response Test for Vitamin A Deficiency in Women of Reproductive Age in Nigeria

Role of endogenous and exogenous antioxidants in risk of six cancers: evidence from the Mendelian randomization study.

Background: Although oxidative stress is known to contribute to cancer, and endogenous and exogenous antioxidants are thought to prevent tumorigenesis by suppressing oxidative stress-induced DNA damage, antioxidants have also been reported to show negative effects on tumor formation, necessitating characterization of the causal associations between antioxidants and cancer risk. Methods: In this study, Mendelian randomization (MR) analysis, primarily inverse-variance weighted MR, was used to assess the causal effect of six endogenous and five exogenous diet-derived antioxidants on the risk of six cancers. MR-Egger intercept test and Cochran's Q statistic were utilized to assess pleiotropy and heterogeneity, respectively. Results: For endogenous antioxidants, a bidirectional two-sample MR analysis was conducted. Our findings suggested that serum albumin has a negative causal association with the risk of prostate cancer [odds ratio (OR) = 0.78, 95% confidence interval (CI): 0.68-0.91, p = 0.001]. The risks of the six cancers showed no significant associations with endogenous antioxidants in the converse MR analysis. For exogenous antioxidants, the unidirectional two-sample MR analysis exhibited a nominal relationship between the serum retinol level and non-small-cell lung cancer risk (OR = 0.29, 95% CI: 0.11-0.76, p = 0.011). Conclusions: Thus, our study revealed the protective effects of genetic susceptibility to high circulating albumin levels on prostate cancer, providing potential targeted interventions for prostate cancer prevention.