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Increased intake of vitamin A (retinoids) is associated with decreased bone mass and increased fracture risk in humans. Mechanistic studies in rodents have shown that hypervitaminosis A results in decreased bone mass caused by an increase in periosteal osteoclasts while simultaneously decreasing endocortic osteoclasts. In vivo and ex vivo bone organ cultures have demonstrated that excess retinoids increase osteoclast formation due to increased receptor activator of nuclear factor kappa B‐ligand (RANKL) expression. In vitro, studies using murine bone marrow macrophages (BMM) have shown that retinoids inhibit osteoclast formation induced by recombinant RANKL. These opposing in vivo/ex vivo versus in vitro effects may elucidate why excess retinoids affect periosteal and endocortic osteoclast formation differently. In addition, it has been reported that retinoids can inhibit osteoclast formation under inflammatory conditions such as experimentally induced arthritis in mice. In the present study, we have compared the effect of all‐trans‐retinoic acid (ATRA) on physiologically and inflammatory induced osteoclastogenesis. ATRA inhibited physiologically induced (RANKL) osteoclast formation of human peripheral blood monocytes and mouse BMM as well as human monocytes stimulated with the pro‐inflammatory compounds, TNF‐α and LPS. The inhibition was due to impeded differentiation, rather than fusion, of mononucleated progenitor cells. ATRA disrupted differentiation by interfering with osteoclastogenic intracellular signaling. In line with this view, overexpression of Tnfrsf11a (encodes for RANK) in BMM could not overcome the inhibition of osteoclastogenesis by ATRA. The data suggest that ATRA inhibits both physiologic and inflammatory osteoclast differentiation of progenitors from the bone marrow and peripheral blood. Retinol inhibits physiological and inflammatory induced osteoclastogenesis in vitro through RARα due to the inhibition of differentiation of mononucleated progenitor cells. [ABSTRACT FROM AUTHOR]

Introduction: the purpose of this study was to assess the vitamin A (VA) nutritional status of patients with coronary artery disease (CAD) and its correlation with the severity of the disease, taking into consideration zinc concentration and oxidative stress.Methods: the patients were preoperative inpatients awaiting myocardial revascularization surgery. The serum concentrations of retinol, β-carotene, zinc, malondialdehyde (MDA) and C-reactive protein (CRP) were quantified. CAD severity was assessed by cineangiography, observing the parameters of severity, extent and occlusion. An echocardiogram was performed to assess the ejection fraction.Results: ninety individuals were studied (64.5 ± 9.6 years). Zinc did not correlate with retinol (r = -0.009/p = 0.40), β-carotene (r = -0.06/p = 0.73) or MDA (r = 0.03/p = 0.70), but zinc deficiency was more frequent amongst the patients with high MDA (quartiles 50 and 75). CRP was found to be associated with retinol (x2 = 3.95/p = 0.04). The individuals with retinol deficiency had more severe CAD, and β-carotene diminished as the extent score rose, although this was not statistically significant (p = 0.12). The degree of severity was associated to extent (x2 = 67.9)/(p < 0.001), occlusion (x2 = 34.5/p < 0.001) and CRP (x2 = 5.9/p = 0.05), while extent was associated with MDA (x2 = 42.1)/(p < 0.001). There was a positive correlation between the ejection fraction and β-carotene (r = 0.42/p = 0.02).Conclusion: findings from this study indicate that chronic inflammation resulting from atherosclerosis is related to disease severity and consequent influence on nutritional status of VA. [ABSTRACT FROM AUTHOR]

Introduction: evidence indicates that vitamin A is involved in regulating fat mass. A low consumption of vitamin A has been reported in individuals with obesity, as have lower concentrations of this vitamin, than in eutrophic individuals when their dietary intake of vitamin A is not significantly different.Objective: to investigate vitamin A nutritional status and its association with body mass index (BMI) and body fat in women who have the recommended dietary intake of vitamin A.Methods: cross-sectional study with 200 women, paired by age and by the dietary intake of vitamin A recommended. Participants were divided into four groups, according to BMI. Anthropometric data were evaluated (weight, BMI and waist circumference [WC]), as well as the diagnosis of night blindness (NB). Lipid and glycemic profiles were measured. The cut-off points for deficiency of serum concentrations of retinol and β-carotene were < 1.05 μmol/l and 40 μg/dl, respectively. The recommended dietary intake of vitamin A was 700 μg/day. RESULTS: there was a significant drop in retinol concentrations according to BMI (p < 0.001) and WC (p < 0.001). We found β-carotene to behave similarly (p = 0.005; p < 0.001). We found NB in 7.5% of overweight (OW) cases and 20.0% of obesity class II (OII), and no functional alteration was found in the eutrophic group (EU). Inadequate levels of retinol and β-carotene increased the odds ratio for the occurrence of OW, obesity class I (OI) and OII, as well as inadequate WC.Conclusion: even with recommended intake of vitamin A, we found a biochemical and functional inadequacy of vitamin A nutritional status,associated with overweight, obesity and body adiposity. [ABSTRACT FROM AUTHOR]

Introduction: it is widely reported that oxidative stress increases in patients undergoing cardiovascular surgery and causes negative outcomes, such as reduced immunological responses and postoperative complications. In this context, vitamin A and zinc serves an important function in the immunological system because it plays a role in fighting oxidative stress.Objectives: to evaluate the effect of vitamin A supplementation on oxidative stress levels in cardiac surgery patients based on zinc nutritional status.Methods: a control group (G1) and a vitamin A intervention group (G2- 5,000 IU of vitamin A daily) were subdivided based on their zinc nutritional status. The patients' serum concentrations of retinol, β-carotene, zinc and malondialdehyde were assessed before surgery (T0), on the 3rd (T1) and 21st postoperative day (T2).Results: in the individuals with adequate zinc concentrations, the retinol concentrations were significantly higher in G2 than in G1 at T1 and T2. In G2, the β-carotene concentrations were significantly higher in individuals with adequate zinc concentrations compared to those who had inadequate concentrations at T1 (p = 0.024) and T2 (p = 0.043). After surgery, malondialdehyde levels were significantly higher in individuals who had inadequate zinc concentrations, compared to those who had adequate zinc concentrations. Analyzing the clinical evolution, operative mortality, hospitalization time and length of stay in Intensive Care Unit (ICU) were lower in G2.Conclusion: vitamin A has contributed to the reduction of oxidative stress, particularly in patients with adequate zinc concentrations and, this way, may help decrease the risk of postoperative complications. [ABSTRACT FROM AUTHOR]

Objectives: Previous studies show the association between vitamin A and elevation of plasma triglyceride concentrations. However, limited information exists on the association between vitamin A and plasma HDL cholesterol concentrations. The aim of this study is to investigate the association between plasma HDL cholesterol levels and vitamin A intake in 57 metabolically healthy obese (MHO) Lebanese.Methods: Out of the 112 adult obese participants who had completed anthropometric and biochemical data, 57 (22 males and 35 females) aged 18-62 years old are metabolically healthy and their data are included in this study. A valid semiquantitative food frequency questionnaire (SQFFQ) was used to test vitamin A intake among other antioxidants. The participants were recruited from the database of three dietary clinics across Lebanon.Results: Pearson's correlation coefficient was used to measure the strength of the relationship between vitamin A and plasma HDL cholesterol levels. There was a significant positive correlation (P value = 0.0225) between vitamin A consumption and HDL cholesterol serum levels in obese participants; when vitamin A levels decrease, HDL levels decrease more in female than in male participants.Conclusion: The association between dietary vitamin A, a powerful antioxidant, and high HDL levels is shown in MHO but should be further exploited in future studies. [ABSTRACT FROM AUTHOR]

Objective: The present study aimed to assess infant and young child feeding (IYCF) practices and the tracking of dietary diversity score (DDS), intakes of Fe- and vitamin A-rich foods and meal frequency in a peri-urban area in Nepal. Furthermore, to explore whether sociodemographic factors were associated with tracking patterns of these IYCF practices.Design: Longitudinal study. Monthly food intake was measured by 24 h recall. Four time slots were used (9-12, 13-16, 17-20 and 21-24 months). Tracking of IYCF practices was investigated using generalized estimating equations (GEE) models and Cohen's weighted kappa. Multinominal logistic regression was used to identify determinants for tracking of the IYCF practices.Setting: Bhaktapur municipality, Nepal.Subjects: Children (n 229) aged 9-24 months, randomly selected.Results: Prevalence of minimum meal frequency was higher than for minimum dietary diversity at all time slots. Tracking based on absolute measures (GEE models) was moderate for DDS (0·48) and meal frequency (0·53), and low for intakes of Fe- (0·23) and vitamin A-rich (0·35) foods. Tracking based on rank measured was moderate for DDS and meal frequency, and fair for Fe- and vitamin A-rich foods. Low socio-economic status significantly increased the odds (OR; 95 % CI) of tracking of low v. high DDS (3·31; 1·44, 7·60) and meal frequency (3·46; 1·54, 7·76).Conclusions: Low tracking for intakes of Fe- and vitamin A-rich foods implies that interventions to improve these IYCF practices must address underlying causes for irregular intake to have sustainable effects. [ABSTRACT FROM AUTHOR]

Objective: Introduction of biofortified cassava as school lunch can increase vitamin A intake, but may increase risk of other deficiencies due to poor nutrient profile of cassava. We assessed the potential effect of introducing a yellow cassava-based school lunch combined with additional food-based recommendations (FBR) on vitamin A and overall nutrient adequacy using Optifood (linear programming tool).Design: Cross-sectional study to assess dietary intakes (24 h recall) and derive model parameters (list of foods consumed, median serving sizes, food and food (sub)group frequency distributions, food cost). Three scenarios were modelled, namely daily diet including: (i) no school lunch; (ii) standard 5d school lunch with maize/beans; and (iii) 5d school lunch with yellow cassava. Each scenario and scenario 3 with additional FBR were assessed on overall nutrient adequacy using recommended nutrient intakes (RNI).Setting: Eastern Kenya.Subjects: Primary-school children (n 150) aged 7-9 years.Results: Best food pattern of yellow cassava-based lunch scenario achieved 100 % RNI for six nutrients compared with no lunch (three nutrients) or standard lunch (five nutrients) scenario. FBR with yellow cassava and including small dried fish improved nutrient adequacy, but could not ensure adequate intake of fat (52 % of average requirement), riboflavin (50 % RNI), folate (59 % RNI) and vitamin A (49 % RNI).Conclusions: Introduction of yellow cassava-based school lunch complemented with FBR potentially improved vitamin A adequacy, but alternative interventions are needed to ensure dietary adequacy. Optifood is useful to assess potential contribution of a biofortified crop to nutrient adequacy and to develop additional FBR to address remaining nutrient gaps. [ABSTRACT FROM AUTHOR]

Background and Objectives: This study aimed to investigate the nutritional quality and patterns of lunch menus provided by child care centers in South Korea and Japan.Methods and Study Design: The weekly lunch menus from Monday to Saturday that child care centers provided in November 2014 in South Korea and Japan were analyzed. For Korea, a total of 72 meals provided by 12 centers in Seoul were analyzed by referring to the homepage of the Center for Children's Foodservice Management, which serviced menus for child care centers. For Japan, a total of 30 meals provided by 5 child care centers in Tokyo were analyzed. Nutrient content and pattern in lunch menus were evaluated.Results: The lunch menus in Korea and Japan provided 359.5 kcal (25.7% of the estimated energy requirement) and 376.3 kcal (29.5% of the estimated energy requirement), respectively. 'Rice + Soup + Main dish + Side dish I + Side dish II' were provided in 66.7% of meals in Korea, while various patterns with rice and soup as their bases were provided in Japan.Conclusions: The lunch menus of child care centers in Korea and Japan provide similar amounts of energy, protein, carbohydrate, vitamin A, calcium, and other nutrients. However, there were significant differences in the lunch menu patterns in Korea and Japan. This study provides information about the nutritional content and pattern of lunch menus at child care centers in Asian countries with rice as a staple food. [ABSTRACT FROM AUTHOR]

Nutritional adequacy depends on nutrient intakes and bioavailability which strongly varies with the plant- or animal-origin of foods. The aim was to estimate iron, zinc, protein and vitamin A bioavailability from individual diets, and investigate its relation with the animal-to-plant ratio (A/P) of diets. Bioavailability was estimated in 1899 French diets using diet-based algorithms or food-group specific conversion factors. Nutrient inadequacy was estimated based on i) bioavailability calculated in each individual diet and ii) average bioavailability assumed for Western-diets. Mean iron absorption, zinc absorption, protein quality and β-carotene conversion factor were 13%, 30%, 92%, and 17:1, respectively. Bioavailability displayed a high variability between individual diets, poorly explained by their A/P. Using individual bioavailability led to different inadequacy prevalence than with average factors assumed for Western-diets. In this population, the A/P does not seem sufficient to predict nutrient bioavailability and the corresponding recommended intakes. Nutritional adequacy should be assessed using bioavailability accounting for individual diets composition. [ABSTRACT FROM AUTHOR]

Background. The Road-to-Health booklet (RtHB), a standardised national tool for growth monitoring and the assessment of health among children from birth to five years of age, was introduced in South Africa in February 2011. Objectives. The study assessed the implementation of growth monitoring and promotion, immunisation, vitamin A supplementation, and deworming sections of the RtHB. Caregivers' (CGs) and healthcare workers' (HCWs') knowledge, attitudes and practices were investigated as well as HCWs' perceptions of barriers undermining implementation. Methods. A cross-sectional descriptive study was conducted on a proportional sample of randomly selected primary healthcare facilities across six health districts (35%; n=143) in the Western Cape Province. HCWs involved in the implementation of the RtHB booklet, children (aged 0 - 36 months) and CGs were included. Information was obtained through scrutiny of the RtHB, observation of consultations and structured questionnaires. Results. A total of 2 442 children, 2 481 CGs and 270 HCWs were recruited. Weight measurements (94.7%, n=2 251/2 378) were performed routinely. Less than half (40.2%; n=997/2 481) of CGs reported that their child's growth had been explained to them. Sixty-eight percent of HCWs (n=178/260) correctly identified criteria for underweight classification, whereas only 55% (n=134/245) and 39% (n=95/245) could do so for stunting and wasting, respectively. The RtHB sections were completed adequately for immunisation (89.3%; n=2 171/2 431) and vitamin A supplementation (94.6%; n=1 305/1 379) but not for deworming (48.8%; n=176/361). Most HCWs (93%; n=209/223) knew the correct regimens for vitamin A supplementation, but few CGs knew when treatment was due for vitamin A supplementation (16.4%, n=409/1 646) and deworming (26.2%; n=650/2 481). Potential barriers identified related to inadequate training, staff shortages and limited time. Conclusion. Focused efforts and resources should be channelled towards HCWs' training and monitoring regarding growth monitoring and promotion to optimise utilisation of the RtHB. Mobilisation of community health workers is needed to strengthen community awareness of preventive health interventions. [ABSTRACT FROM AUTHOR]

Objective: Vitamin A supplementation (VAS) for children aged 6-59 months occurs regularly in most sub-Saharan African countries. The present study aimed to explore child, household and delivery platform factors associated with VAS coverage and identify barriers to compliance in thirteen African countries.Design: We pooled data (n ~60 000) from forty-four household coverage surveys and used bivariate and multivariable regression analyses to assess the effects of supplementation strategy, rural v. urban residence, child sex, child age, caregiver education and campaign awareness on child VAS status. Setting/Subjects Primary caregivers of children aged 6-59 months in thirteen countries.Results: Door-to-door distribution resulted in higher VAS coverage than fixed-site plus outreach approaches (91 v. 63 %) and was a significant predictor of supplementation in the adjusted model (OR=19·0; 95 % CI 17·2, 21·1; P<0·001). Having been informed about the campaign was the main predictor of VAS in the door-to-door (OR=6·8; 95 % CI 5·8, 7·9; P<0·001) and fixed-site plus outreach (OR=72·5; 95 % CI 66·6, 78·8; P<0·001) groups.Conclusions: Door-to-door provision of VAS may achieve higher coverage than fixed-site models in the African context. However, the phase-out of door-to-door polio immunization campaigns in most sub-Saharan African countries threatens the main distribution vehicle for VAS. Our findings suggest well-informed communities are key to attaining higher coverage using fixed-site delivery alternatives. [ABSTRACT FROM AUTHOR]

Objective: To describe: household dietary diversity across four zones in Ethiopia; the relationship between household dietary diversity and consumption of vitamin A-rich foods; and the relationship between household dietary diversity and food security status.Design: This was a cross-sectional survey. Data were collected using structured questionnaires in the local language. Household dietary diversity scores measured types of foods households consumed, and households were classified by food security status using a modified version of the Household Food Insecurity Access Scale. An ordinal logistics regression model was created to assess the relationship between three tiers of dietary diversity (low, medium and high) and food security while controlling for agricultural zone, educational variables and household characteristics.Setting: Rural households in Tigray, Ethiopia.Subjects: Three hundred households in Tigray, Ethiopia, were interviewed.Results: Of the households, 23, 47 and 30 % had low, medium and high dietary diversity, respectively. Among households with high dietary diversity, eggs and fruit were the most common foods added to the diet. In the fully adjusted model, participants who reported being food secure had 1·8 increased odds of greater dietary diversity (95 % CI 1·0, 3·2) compared with participants who were food insecure.Conclusions: Food security was positively associated with dietary diversity. In order to enhance health, interventions that improve dietary diversity and vitamin A consumption should remain important areas of focus for health leaders in the region. [ABSTRACT FROM AUTHOR]

Introduction: Carotenoids are plant pigment with important biological activities in humans, such as provitamin-A among others. At present, there are no individual carotenoid intake data in the Dominican population, which is at risk of vitamin A deficiency and has an important percentage of overweight and obese individuals .Objective: To assess the individual components of vitamin A intake (retinol, α-carotene, β-carotene and β-cryptoxanthin) and that of other relevant dietary carotenoids like lutein, zeaxanthin and lycopene of Dominican daily food intake.Methods: Fifty overweigth and obese subjects (22-69 y). Individual carotenoid intake, from whole diet and from the ingestion of fruits and vegetables, was determined using three 24 h diet recalls and a specific carotenoid database. Retinol, macronutrient and energy intake were calculated using DIAL® software.Results: The total carotenoid intake was 6363.2 µg/day, 56. 1% corresponding to provitamin A carotenoids (74.3% β-carotene). Vitamin A intake was supplied by retinol (40%) and by provitamin A carotenoids (60%); vegetables contributed more than fruits (39.2% and 19.2%, respectively). Non-provitamin A carotenoid intake represents 43.9% of the total intake and is supplied by lycopene and lutein plus zeaxanthin in similar percentages (52.3% and 47.7%, respectively).Conclusions: The diet of these Dominican subjets met the recommended vitamin A intake, when expressed as retinol equivalents, 59% of which was supplied by provitamin-A carotenoids from plant sources, mainly by red/orange and white/yellow foods. Individual carotenoid intake is an aspect of great interest for issuing dietary recommendations in the public health setting. [ABSTRACT FROM AUTHOR]

Background: Assessment of high-dose vitamin A supplementation (VAS) coverage often relies on postevent coverage (PEC) surveys, but the validity of these methods has rarely been evaluated.Objectives: To assess reported VAS coverage and factors associated with missed coverage and to investigate the reliability of the results.Methods: During a cross-sectional survey, 10 454 caregivers of children <27 months old were asked whether their child had received VAS in the past 6 months. During a 48-week longitudinal study of 6232 children 6 to 30 months old, caregivers were asked every 4 weeks if their child had received VAS in the past 4 weeks.Results: The cross-sectional study showed that 94.4% (95% confidence interval [CI]: 93.8%, 94.9%) of eligible children 6 to 26 months of age reportedly received VAS in the previous 6 months, as did 85.8% (CI: 84.5%, 87.2%) of ineligible, 0 to 5 months old children. The longitudinal study showed that 81.6% of children surveyed within 4 weeks following a VAS campaign reportedly received VAS during the campaign and 13.4% of caregivers incorrectly reported receiving VAS when no campaign had actually occurred. False-positive reporting was more likely when oral polio vaccine (OPV) was distributed during the reporting period (20.6% vs 5.4%; P < .001). Showing a photo of OPV during the interview reduced the odds ratio (OR) of false-positive reports (OR = 0.7 [0.6-0.8]).Conclusions: The PEC surveys should include children outside the target age to assess targeting efficiency, and pictures of both VAS and oral vaccines distributed during the same period should be shown during interviews to enhance reporting accuracy. [ABSTRACT FROM AUTHOR]

Background: Retinol isotope dilution (RID) equations are used to determine vitamin A status and the efficacy of vitamin A intervention programs. Recent work related to RID methods has focused on modifying the "Olson equation" to improve the accuracy of predictions of vitamin A total body stores (TBS) in individual subjects.Objective: We investigated the hypothesis that short-term restriction of vitamin A intake would result in accurate RID prediction of vitamin A TBS in individuals.Methods: We applied model-based compartmental analysis to a 6-component model derived from published retinol kinetic studies on 12 individuals with a wide range of vitamin A stores and determined vitamin A TBS in the steady state. Then we simulated the impact of eliminating or strictly limiting vitamin A intake at the time of isotope administration, while maintaining plasma retinol homeostasis, on retinol specific activity in plasma (SAp; fraction of dose/μmol retinol) and stores, and we calculated TBS using the simplified RID equation TBS = 0.75 × 1/SAp, where the fractional absorption of tracer was set at 0.75 and SAp was simulated 5 d after dosing.Results: When vitamin A intake was zero or strictly limited (0.25 μmol/d), mean TBS predicted by the equation at 5 d after dose administration divided by TBS determined by using the model was 1.00 (range: 0.959-1.04) or 1.02 (range: 0.983 - 1.06), respectively.Conclusions: By eliminating or strictly limiting vitamin A input, isotopic equilibrium was reached by 5 d. At isotopic equilibrium, SAp is the same as that in the body's exchangeable vitamin A pools; under these conditions, SAp may be measured at any time from 5 d on and used to calculate TBS. [ABSTRACT FROM AUTHOR]

Background: Micronutrient deficiency in Tanzania is a significant public health problem, with vitamin A deficiency (VAD) affecting 34% of children aged 6 to 59 months. Since 2007, development partners have worked closely to advocate for the inclusion of twice-yearly vitamin A supplementation and deworming (VASD) activities with budgets at the subnational level, where funding and implementation occur. As part of the advocacy work, a VASD planning and budgeting tool (PBT) was developed and is used by district officials to justify allocation of funds. Helen Keller International (HKI) and the Tanzania Food and Nutrition Centre (TFNC) conduct reviews of VASD funds and health budgets annually in all districts to monitor the impact of advocacy efforts. This paper presents the findings of the fiscal year (FY) 2010 district budget annual review. The review was intended to answer the following questions regarding district-level funding: (1) how many funds were allocated to nutrition-specific activities in FY 2010? (2) how many funds were allocated specifically to twice-yearly VASD activities in FY 2010? and (3) how have VASD funding allocations changed over time? Methods: Budgets from all 133 districts in Tanzania were accessed, reviewed and documented to identify line item funds allocated for VASD and other nutrition activities in FY 2010. Retrospective data from prior annual reviews for VASD were used to track trends in funding. The data were collected using specific data forms and then transcribed into an excel spreadsheet for analysis. Results: The total funds allocated in Tanzania's districts in FY 2010 amounted to US$1.4 million of which 92% were for VASD. Allocations for VASD increased from US$0.387 million to US$1.3 million between FY 2005 and FY 2010. Twelve different nutrition activities were identified in budgets across the 133 districts. Despite the increased trend, the percentage of districts allocating sufficient funds to implement VAS (as defined by cost per child) was just 21%. Discussion: District-driven VAS funding in Tanzania continues to be allocated by districts consistently, although adequacy of funding is a concern. However, regular administrative data point to fairly high and consistent coverage rates for VAS across the country (over 80% over the last 10 years). Although this analysis may have omitted some nutrition-specific funding not identified in district budget data, it represents a reliable reflection of the nutrition funding landscape in FY 2010. For this year, total district nutrition allocations add up to only 2% of the amount needed to implement nutrition services at scale according to Tanzania's National Nutrition Strategy Implementation Plan. Conclusion: VASD advocacy and planning support at the district level has succeeded in ensuring district allocations for the program. To promote sustainable implementation of other nutrition interventions in Tanzania, more funds must be allocated and guidance must be accompanied by tools that enable planning and budgeting at the district level. [ABSTRACT FROM AUTHOR]

Background: The most rapid phase of brain development occurs during the neonatal period. Vitamin A (VA; retinol) is critical for many aspects of this process, including neurogenesis, synaptic plasticity, learning, and memory formation. However, the metabolism of retinol in the neonatal brain has not been extensively explored.Objective: We examined the uptake of VA into the brain in neonatal rats raised under VA-marginal conditions (control group) and assessed the effect of VA supplementation on the uptake of VA into the brain.Methods: Sprague-Dawley neonatal rats (n = 104) nursed by mothers fed a VA-marginal diet were randomly assigned and treated on postnatal day 4 with an oral dose of either VA (6 μg retinyl palmitate/g body weight) or canola oil as the control, both of which contained 1.8 μCi [(3)H]retinol. Pups (n = 4/group at a time) were killed at 13 sampling times from 30 min to 24 d after dosing. The uptake of total retinol, chylomicron-associated retinyl esters (REs), and retinol bound to retinol-binding protein (RBP) was estimated with the use of WinSAAM version 3.0.8.Results: Total retinol mass in the brain was closely dependent on its mass in plasma over time (r = 0.91; P < 0.001). The uptake of retinol into the brain involved both postprandial chylomicrons and RBP, with RBP delivering most of the retinol in the control group [0.27 nmol/d (RBP) compared with 0.01 nmol/d (chylomicrons)]. VA supplementation increased the fractional uptake of chylomicron REs from 0.3% to 1.2% of plasma pool/d, decreased that of RBP retinol from 0.5% to 0.2% of plasma pool/d, and increased the transfer rate of chylomicron REs from nearly zero to 0.7 nmol/d, causing a day-long elevation in the brain mass of total retinol.Conclusion: Postprandial chylomicrons may be a primary mechanism for delivering a recently ingested large dose of VA to the brain of neonatal rats raised under VA-marginal conditions. [ABSTRACT FROM AUTHOR]

A randomised, double-blind, placebo-controlled trial was carried out among Mexico children aged 6–15 months to determine how household characteristics modify vitamin A and zinc supplementation efficacy on Ascaris lumbricoides, Giardia intestinalis and Entamoeba histolytica/E. dispar infection durations. Children assigned to receive vitamin A every 2 months, a daily zinc supplement, a combined vitamin A-zinc supplement or a placebo were followed for 1 year. Parametric hazard models were fit to infection durations stratified by personal and household factors. Children supplemented with vitamin A and zinc combined from households lacking piped water and children in all three treatment arms from households with dirt floors had longer G. intestinalis and A. lumbricoides infection durations than their counterparts, respectively. Shorter E. histolytica/E.dispar durations were found among zinc-supplemented children of mothers who had <6 years of education and no indoor bathrooms. Heterogeneity in supplementation efficacy among children may reflect differences in exposure risk and baseline immune responses. [ABSTRACT FROM AUTHOR]

Background: Vitamin A deficiency remains a global public health problem. Daily supplementation with a lipid-based nutrient supplement (LNS) has potential for increasing milk vitamin A concentrations.Objective: The objective of this study was to determine whether daily supplementation with approximately the recommended daily intake of vitamin A in an LNS or a multiple-micronutrient supplement (MMN) during pregnancy and the first 6 mo postpartum has an effect on breast milk retinol concentration at 6 mo postpartum.Methods: Women ≤20 wk pregnant (n = 1320) were randomly assigned to receive either the MMN providing 18 micronutrients, including 800 μg retinol equivalents of vitamin A, or the LNS with the same nutrients as the MMN group, plus 4 minerals and macronutrients, until 6 mo postpartum; a control group received iron and folic acid during pregnancy and a placebo (calcium tablet) during the first 6 mo postpartum. Breast milk samples collected at 6 mo postpartum were analyzed for retinol and fat concentrations by HPLC and creamatocrit, respectively, in a subsample of 756 women.Results: The breast milk retinol concentration was (mean ± SD) 56.3 ± 2.1 nmol/g fat, with no significant differences between groups [iron and folic acid (n = 243): 59.1 ± 2.8; MMN (n = 260): 55.4 ± 2.5; LNS (n = 253): 54.7 ± 2.5 nmol/g fat; P = 0.45], regardless of whether the woman had or had not received a high-dose vitamin A supplement (200,000 IU) soon after childbirth. Around 17% of participants had low milk retinol (≤28 nmol/g fat). We estimated that 41% of infants were potentially receiving vitamin A at amounts above the Tolerable Upper Intake Level (600 μg retinol activity equivalents/d), with no group differences in percentages with low or high milk retinol concentration.Conclusion: Daily consumption of approximately the recommended intake of vitamin A did not increase breast milk retinol concentrations in this sample of Ghanaian women. This trial was registered at clinicaltrials.gov as NCT00970866. [ABSTRACT FROM AUTHOR]

Vitamin A (VA, retinol) metabolism is homeostatically controlled, but little is known of its regulation in the postnatal period. Here, we determined the postnatal trajectory of VA storage and metabolism in major compartments of VA metabolism–plasma, liver, lung, and kidney from postnatal (P) day 1 to adulthood. We also investigated the response to supplementation with VARA, a combination of VA and 10% all-trans-retinoic acid that previously was shown to synergistically increase retinol uptake and storage in lung. Nursling pups of dams fed a VA-marginal diet received an oral dose of oil (placebo) or VARA on each of four neonatal days: P1, P4, P7, and P10; and again as adults. Tissues were collected 6 h after the final dosing on P1, P4, P10, and at adult age. Gene transcripts for Lrat and Rbp4 in liver and Raldh-1 and Raldh-3 in lung, did not differ in the neonatal period but were higher, P<0.05, in adults, while Cyp26B1, Stra6, megalin, and Raldh-2 in lung did not differ from perinatal to adult ages. VARA supplementation increased total retinol in plasma, liver and lung, with a dose-by-dose accumulation in neonatal liver and lung, while transcripts for Lrat in liver, megalin in kidney, Cyp26A1/B1 in liver and lung, respectively, and Stra6 in lung, were all increased, suggesting pathways of VA uptake, storage and RA oxidation were each augmented after VARA. VARA decreased hepatic expression of Rbp4, responsible for VA trafficking from liver to plasma, and, in lung, of Raldh-1 and Raldh-2, which function in RA production. Our results define retinoid homeostatic gene expression from neonatal and adult age and show that while supplementation with VARA acutely alters retinol content and retinoid homeostatic gene expression in neonatal and adult lung, liver and kidney, VARA supplementation of neonates increased adult-age VA content only in the liver. [ABSTRACT FROM AUTHOR]

This study aimed to develop and evaluate the validity of a food frequency questionnaire (FFQ) for rural Rwandans. Since our FFQ was developed to assess malnutrition, it measured energy, protein, vitamin A, and iron intakes only. We collected 260 weighed food records (WFRs) from a total of 162 Rwandans. Based on the WFR data, we developed a tentative FFQ and examined the food list by percent contribution to energy and nutrient intakes. To assess the validity, nutrient intakes estimated from the FFQ were compared with those calculated from three-day WFRs by correlation coefficient and cross-classification for 17 adults. Cumulative contributions of the 18-item FFQ to the total intakes of energy and nutrients reached nearly 100%. Crude and energy-adjusted correlation coefficients ranged from -0.09 (vitamin A) to 0.58 (protein) and from -0.19 (vitamin A) to 0.68 (iron), respectively. About 50%-60% of the participants were classified into the same tertile. Our FFQ provided acceptable validity for energy and iron intakes and could rank Rwandan adults in eastern rural area correctly according to their energy and iron intakes. [ABSTRACT FROM AUTHOR]

Objective: The objective of this study was analytical assessment of the concentration of selected antioxidants as well as total antioxidant capacity of daily diets of children and adolescents from orphanages in Krakow (Poland).Methods: Daily diets of children and adolescents were collected in 4 seasons of the year from 7 orphanages located in Krakow. The concentrations of vitamin C, β-carotene, polyphenolic compounds, and antioxidant capacity were measured.Results: The lowest content of vitamin C in diets of children and adolescents was measured in diets collected in autumn. The estimated average requirement (EAR) was in the range 49.0%-76.4%. In winter the content of this compound was significantly higher in daily diets (113.9%-192.0% coverage of EAR) compared to the level of this nutrient in daily diets from other seasons. The content of β-carotene, lower than 50% of EAR value, calculated as the vitamin A equivalent, has been demonstrated in 4 orphanages in summer and in one in spring and autumn. The highest mean content of this antioxidant in daily diets was found in winter, when β-carotene intake met recommendations in the range 131%-368%. The mean concentration of polyphenolic compounds per year was in the range 301.5-537.5 mg/person/day. It has been observed that diets during the winter and autumn generally provide higher amounts of polyphenols than in other seasons. The highest antioxidant activity was measured in diets collected during the winter season.Conclusions: The results indicate that the diets of children and adolescents should contain more fresh vegetables and fruits, which are good source of natural antioxidants. [ABSTRACT FROM AUTHOR]

Objective: The objective of the present study is to evaluate the nutritional status of vitamin A through biochemical and functional indicators of pregnant women who underwent Roux-en-Y gastric bypass (RYGB) surgery compared to pregnant women who did not undergo this surgery. Methods: The present study is a cross-sectional study of the analytical type with pregnant women paired by age and prepregnancy body mass index (BMI). Group 1 (G1) comprised 80 pregnant women without previous submission to RYGB and group 2 (G2) by 40 pregnant women who previously underwent this surgery. We used high-performance liquid chromatography with UV detector for quantification of retinol and β-carotene, and the functional evaluation of vitamin A deficiency (VAD) was performed through standardized interview validated for pregnant women. Results: G1 mean age was 29.3 ± 5.3 and 30.8 ± 4.4 in G2. BMI mean prepregnancy found in G1 was 25.7 ± 3.2 and 26.8 ± 3.1 in G2, featuring overweight. Serum retinol and β-carotene means were significantly higher in G1 (1.8 ± 0.9; 87.4 ± 62.2) compared to G2 (0.99 ± 0.39; 22.7 ± 18.0), respectively ( p < 0.001). Regarding the functional indicator for evaluation of VAD, approximately 75.0 % of pregnant women in G2 showed night blindness and 20.0 % in G1, and the percentage of pregnant women with this functional impairment was significantly higher in G2 compared to G1 with p < 0.001. Conclusion: Results show that pregnancy after RYGB can represent a high-risk situation for VAD. We recommend interdisciplinary monitoring added to the prenatal routine consultations and the conduction of studies addressed to the investigation of a safe and effective dose of oral supplementation of vitamin A to pregnant women undergoing RYGB. [ABSTRACT FROM AUTHOR]

ObjectiveTo assess oil consumption, vitamin A intake and retinol status before and a year after the fortification of unbranded palm oil with retinyl palmitate.DesignPre–post evaluation between two surveys.SettingTwenty-four villages in West Java.SubjectsPoor households were randomly sampled. Serum retinol (adjusted for subclinical infection) was analysed in cross-sectional samples of lactating mothers (baseline n 324/endline n 349), their infants aged 6–11 months (n 318/n 335) and children aged 12–59 months (n 469/477), and cohorts of children aged 5–9 years (n 186) and women aged 15–29 years (n 171), alongside food and oil consumption from dietary recall.ResultsFortified oil improved vitamin A intakes, contributing on average 26 %, 40 %, 38 %, 29 % and 35 % of the daily Recommended Nutrient Intake for children aged 12–23 months, 24–59 months, 5–9 years, lactating and non-lactating women, respectively. Serum retinol was 2–19 % higher at endline than baseline (P<0·001 in infants aged 6–11 months, children aged 5–9 years, lactating and non-lactating women; non-significant in children aged 12–23 months; P=0·057 in children aged 24–59 months). Retinol in breast milk averaged 20·5 μg/dl at baseline and 32·5 μg/dl at endline (P<0·01). Deficiency prevalence (serum retinol <20 μg/dl) was 6·5–18 % across groups at baseline, and 0·6–6 % at endline (P≤0·011). In multivariate regressions adjusting for socio-economic differences, vitamin A intake from fortified oil predicted improved retinol status for children aged 6–59 months (P=0·003) and 5–9 years (P=0·03).ConclusionsAlthough this evaluation without a comparison group cannot prove causality, retinyl contents in oil, Recommended Nutrient Intake contributions and relationships between vitamin intake and serum retinol provide strong plausibility of oil fortification impacting vitamin A status in Indonesian women and children. [ABSTRACT FROM PUBLISHER]

Background: Retinol is a lipid-soluble essential nutrient that is stored as retinyl esters in lipid droplets of hepatic stellate cells. Patatin-like phospholipase domain-containing 3 (PNPLA3), through its retinyl-palmitate lipase activity, releases retinol from lipid droplets in hepatic stellate cells in vitro and ex vivo. We have shown that the genetic variant I148M (rs738409) reduces the PNPLA3 retinyl-palmitate lipase activity. Objective: The aim of the present genetic association study was to test whether overweight/obese carriers of the PNPLA3 148M mutant allele had lower circulating concentrations of retinol than individuals who are homozygous for the 148I allele. Methods: PNPLA3 I148M (rs738409) was genotyped by Taqman assay in 76 overweight/obese individuals [BMI (kg/m²) ≥25; mean ± SD age: 59.7 ± 11.4 y; male gender: 70%] with a histologic diagnosis of nonalcoholic fatty liver disease (NAFLD; namely the Milan NAFLD cohort) and in 413 obese men (BMI ≥30; mean ± SD age: 57.1 ± 4.9 y) from the α-Tocopherol, β-Carotene Cancer Prevention (ATBC) Study. Serum concentrations of retinol and α-tocopherol were measured by HPLC in both cohorts. β-Carotene concentrations in the ATBC study were measured by using HPLC. Results: The PNPLA3 148M mutant allele was associated with lower fasting circulating concentrations of retinol (β = -0.289, P = 0.03) in adults with NAFLD (Milan NAFLD cohort). The PNPLA3 148M mutant allele was also associated with lower fasting circulating concentrations of retinol in adults with a BMI ≥30 (ATBC study; β = -0.043, P = 0.04). Conclusion: We showed for the first time, to our knowledge, that carriers of the PNPLA3148M allele with either fatty liver plus obesity or obesity alone have lower fasting circulating retinol concentrations. [ABSTRACT FROM AUTHOR]

Background: In recent decades, the general socioeconomic situation in Latin America and the Caribbean countries has improved, and many vitamin A programs have been implemented in an attempt to reduce vitamin A deficiency in the region. Objective: To examine vitamin A status in Latin America and the Caribbean based on serum retinol concentrations and to contrast available data published before and after 1998. Methods: A systematic review was performed. National surveys or representative studies that reported vitamin A status were selected. Results: Ten national surveys and six representative studies were identified. Data for children under 6 years of age indicate that Guatemala and Nicaragua have practically eradicated vitamin A deficiency (less than 2% prevalence of serum retinol < 20 μg/dL). In Costa Rica, Cuba, El Salvador, and Panama, the prevalence of vitamin A deficiency ranged from 2.8% to 9.4%. In Peru, Honduras, Argentina, Ecuador, and Brazil, vitamin A deficiency is a moderate public health problem (prevalence from 14.0% to 17.4%), while in Colombia, Mexico, and Haiti it is a severe public health problem (prevalence from 24.3% to 32.0%). Disadvantaged groups (indigenous people and those of Afro-Colombian descent) have the highest rates of deficiency. The prevalence of vitamin A deficiency is under 20% in schoolchildren and adult women. When data published before and after 1998 for children under 6 years of age were compared, most Central American countries had a reduction in the prevalence of vitamin A deficiency (p < .05), whereas in South American countries, the prevalence of vitamin A deficiency increased over time (p < .05). Conclusions: The prevalence of vitamin A deficiency in children under 6 years of age has decreased in many Central American countries, but vitamin A deficiency still remains a public health problem in numerous Latin America and Caribbean countries, especially among disadvantaged and vulnerable groups. Because of issues with the accuracy of the serum retinol biomarker reflecting body stores, these results must be interpreted with caution. [ABSTRACT FROM AUTHOR]

Background: High serum Retinol Binding Protein 4 (RBP4) levels were associated with insulin-resistant states in humans. To determine which fat compartments are associated with elevated RBP4 levels in humans, we measured serum RBP4 and hepatic fat content (HFC), visceral (VFA) and subcutaneous abdominal fat area (SFA) in 106 subjects with non-alcoholic fatty liver disease (NAFLD) without known diabetes. Methods: 106 patients with NAFLD (M/F: 61/45, aged 47.44 ± 14.16 years) were enrolled. Subjects with known diabetes, chronic virus hepatitis, and those with alcohol consumption ≥30 g/d in man and ≥20 g/d in woman were excluded. Anthropometrics and laboratory tests, including lipid profile, alanine aminotransferase (ALT), aspartate aminotransferase (AST) and γ-glutamyltransferase (γ-GT) were conducted. HFC, VFA and SFA were determined by CT scan. Serum RBP4 was detected by an enzyme immunoassay kit and validated by quantitative Western blotting. Results: Circulating RBP4 was negatively associated with high-density lipoprotein cholesterol (HDL-c) (r = -0.392, p < 0.001), but positively with waist-to-hip ratio (WHR) (r = 0.343, p = 0.001), triglyceride (r = 0.330, p = 0.002), VFA (r = 0.298, p = 0.027), systolic blood pressure (r = 0.247, p = 0.020), diastolic blood pressure (r = 0.241, p = 0.023), γ-GT (r = 0.239, p = 0.034), waist circumference (r = 0.218, p = 0.040). Differently, serum RBP4 levels were not associated with HFC (r = 0.199, p = 0.071), SFA, age, BMI, total cholesterol, low-density lipoprotein cholesterol (LDL-c), ALT or AST (all p > 0.05). Multiple linear regression analysis revealed that RBP4 correlated independently with VFA (Standard β = 0.357, p = 0.019) and HDL-c (Standard β = -0.345, p = 0.023) in all subjects, HDL-c (Standard β = -0.315, p = 0.040) in men, VFA/SFA in women (Standard β = 0.471, p = 0.049), not with HFC. However, serum RBP4 was positively correlated with HFC when HFC below 6.34% (r = 0.574, p = 0.001). Conclusions: RBP4 could be a marker of abdominal obesity, however, the role of RBP4 in the pathogenesis of NAFLD is not sufficiently elucidated. [ABSTRACT FROM AUTHOR]

Following a request from the European Commission, the Panel on Dietetic Products, Nutrition and Allergies derived Dietary Reference Values for vitamin A. The Panel considered that a concentration of 20 µg retinol/g liver can be used as a target for establishing the Average Requirement (AR) for vitamin A. In the absence of a better characterisation of the relationship between vitamin A intake and liver stores, a factorial approach was applied. This approach considered a total body/liver retinol store ratio of 1.25, a liver/body weight ratio of 2.4 %, a fractional catabolic rate of body retinol of 0.7 % per day, an efficiency of storage in the whole body for ingested retinol of 50 % and reference weights for women and men in the EU of 58.5 and 68.1 kg, respectively. ARs of 570 µg retinol equivalent (RE)/day for men and 490 µg RE/day for women were derived. Assuming a coefficient of variation (CV) of 15 %, Population Reference Intakes (PRIs) of 750 µg RE/day for men and 650 µg RE/day for women were set. For infants aged 7-11 months and children, the same equation as for adults was applied by using specific values for reference weight and liver/body weight ratio. For catabolic rate, the adult value corrected on the basis of a growth factor was used. ARs range from 190 µg RE/day in infants aged 7-11 months to 580 µg RE/day in boys aged 15-17 years. PRIs for infants and children were estimated using a CV of 15 % and range from 250 to 750 µg RE/day. For pregnancy and lactation, additional vitamin A requirements related to the accumulation of retinol in fetal and maternal tissues and transfer of retinol into breast milk were considered and PRIs of 700 and 1 300 µg RE/day, respectively, were set. [ABSTRACT FROM AUTHOR]

Pregnancy exacerbates vitamin A (VA) deficiency and anaemia among women in developing countries. Improving circulating haemoglobin (Hb) requires erythrocyte production and availability of iron. Insulin-like growth factor-1 (IGF-1) functions in erythropoiesis, but its association with VA status and pregnancy-associated anaemia has not been studied. The aim of this study was to examine the relationship between serum retinol, IGF-1, and Hb among pregnant women in extant samples collected during a placebo-controlled trial of VA and beta-carotene (BC) supplementation in rural Nepal conducted from 1994 to 1997. Mid-pregnancy serum IGF-1 was measured in serum from n=589 randomly selected women of n=1186 in whom anthropometric, VA (retinol) and iron (Hb, erythrocyte zinc protoporphyrin (ZP), and ferritin) status data were available. Associations of IGF-1 with retinol, Hb or anaemia, and iron status were determined using multiple linear and logistic regression. Path analysis was used to explore the role of IGF-1 as a mediator between retinol and Hb, accounting for iron status. A 2.6 g/L increase in IGF-1 was observed per 0.1 mol/L increment in retinol (p<0.0001). Hb increased with each quartile of IGF-1, and odds of anaemia declined 68.8% from the 1st to 4th quartile. Improved iron status indicators explained only 29.1% of the association between IGF-1 and Hb, while IGF-1 explained 25.6% of the association between retinol and Hb. Increasing IGF-1 was likely one mechanism by which retinol improved circulating Hb in pregnant women of rural Nepal, although IGF-1 worked primarily through pathways independent of improved iron status indicators, perhaps by stimulating erythrocyte production. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate vitamin A concentration in mature breast milk of nursing mothers aiming to meet the daily needs and the formation of liver reserve in pre-term (PT) and term infants (T) in comparison with the recommended intake for this nutrient in this group. Methods: We analyzed the retinol concentration in the milk of 120 nursing mothers (40 of PT infants and 80 of T infants) by collecting 10 mL of mature breast milk, held by a hand spray of one of the breasts 2 h after the last feeding in the morning. The cutoff points adopted for identification of vitamin A deficiency (VAD) and the liver reserve were <1.05 and >2.3 μmol/L, respectively. Results: The concentrations of retinol in the human milk of T infants were superior to concentrations in the milk of PT infants (1.87 + 0.81 > 1.38 + 0.67 μmol/L, p < 0.0001). They were higher in T compared to PT (352.64 + 152.72 > 217.65 + 105.65 μg, p < 0.0001), but both were below the recommendation. VAD was 20.0 % (T) and 27.5 % (PT). Only 40.0 % (T) and 22.5 % (PT) of the mothers had retinol concentrations in milk above 2.3 mmol/L. Conclusion: The milk of the nursing mothers studied did not have enough retinol to meet the daily needs and to form liver reserve in both groups, especially in PT newborns. This finding reinforces the idea that supplementation with massive doses of vitamin A in the immediate postpartum period can be used as a protective device of the infant against VAD. [ABSTRACT FROM AUTHOR]

Although vitamin A was recognized as an "anti-infective vitamin" over 90 years ago, the mechanism of how vitamin A regulates immunity is only beginning to be understood. Early studies which focused on the immune responses in vitamin A-deficient (VAD] animals clearly demonstrated compromised immunity and consequently increased susceptibility to infectious disease. The active form of vitamin A, retinoic acid (RA], has been shown to have a profound impact on the homing and differentiation of leukocytes. Both pharmacological and genetic approaches have been applied to the understanding of how RA regulates the development and differentiation of various immune cell subsets, and how RA influences the development of immunity versus tolerance. These studies clearly show that RA profoundly impacts on cell- and humoralmediated immunity. In this review, the early findings on the complex relationship between VAD and immunity are discussed as well as vitamin A metabolism and signaling within hematopoietic cells. Particular attention is focused on how RA impacts on T-cell lineage commitment and plasticity in various diseases. [ABSTRACT FROM AUTHOR]

Secondary lymphoid organs form in utero through an inherited and well-established developmental program. However, maternal non-heritable features can have a major impact on the gene expression of the embryo, hence influencing the future health of the offspring. Recently, maternal retinoids were shown to regulate the formation of immune structures, shedding light on the role of maternal nutrition in the genetic signature of emergent immune cells. Here we highlight evidence showing how the maternal diet influences the establishment of the immune system, and we also discuss how unbalanced maternal diets may set the response to infection and vaccination in the progeny. [ABSTRACT FROM AUTHOR]

Background: The WHO recommends assessing food and nutrient intakes to design food-fortification programs, but nationally representative dietary data are seldom available in low-income countries. Objective: Prior to initiation of food fortification in Cameroon, we measured intake of vitamin A (VA) and fortifiable foods (vegetable oil, sugar, wheat flour, and bouillon cube) to simulate the effects of fortification with different foods and VA amounts on prevalence of inadequate and excessive VA intake. Methods: Twenty-four-hour recalls were conducted among 912 women and 883 children (with duplicates in a subset) in a nationally representative cluster survey stratified by region (North, South, Yaounde/Douala). Usual intake distributions were estimated by the National Cancer Institute method. Results: Nationally, 53% of women had a usual intake of <500 pig retinol activity equivalents/d, and 59% of nonbreastfeeding children had an intake of <210 µg retinol activity equivalents/d, although VA intake varied by region. The current fortification program (12 mg/kg VA in oil) would decrease the prevalence of inadequate intakes to 35% among both women and children, without increasing the proportion with retinol intakes >3000 µg/d among women or >600 µg/d among children. However, inadequate VA intake would remain >50% in the North, where VA deficiency was most common. Increasing VA in oil or fortifying a second food (sugar, wheat flour, or bouillon cube) would further decrease the prevalence of inadequate intakes, but, depending on the food vehicle and region, would also increase the prevalence of retinol intakes above the tolerable upper intake level, mainly among children. Conclusions: The current food-fortification program can be expected to improve dietary VA adequacy without increasing the risk of excessive intake among women and children in Cameroon. Modifications to the program must balance the potential to further increase VA intake with the risk of excessive intake among children. [ABSTRACT FROM AUTHOR]

Retinoids are a class of chemical compounds which include both natural dietary vitamin A (retinol) metabolites and active synthetic analogs. Both experimental and clinical studies have revealed that retinoids regulate a wide variety of essential biological processes. In this study, we synthesized 11 C-labeled all-trans-retinoic acid (ATRA), the most potent biologically active metabolite of retinol and used in the treatment of acute promyelocytic leukemia. The synthesis of 11 C-labeled ATRA was accomplished by a combination of rapid Pd(0)-mediated C -[ 11 C]methylation of the corresponding pinacol borate precursor prepared by 8 steps and hydrolysis. [ 11 C]ATRA will prove useful as a PET imaging agent, particularly for elucidating the improved therapeutic activity of ATRA (natural retinoid) for acute promyelocytic leukemia by comparing with the corresponding PET probe [ 11 C]Tamibarotene (artificial retinoid). [ABSTRACT FROM AUTHOR]

Milk fat contains a large number of fatty acids (FA) and other liposoluble components that exhibit various effects on human health. The present article reviews some of the factors affecting FA, vitamin A and cholesterol concentrations in milk from dairy cow and goat. Milk fat composition is linked to many factors, both intrinsic (animal species, breed, lactation stage) and extrinsic (environmental). The effect of animal species on milk fat composition is important, as reflected by higher concentrations of shortand medium-chain FA, vitamin A and cholesterol in goat than in cow milk. In a given ruminant species, the effects linked to breed are significant but limited and they can only be achieved over long periods of time. The lactation stage has an important effect on milk FA composition, mainly linked to body fat mobilisation in early lactation, but it only lasts a few weeks each year. Furthermore, changes in feeding have a marked influence on milk fat composition. Changing the forages in the diet of ruminants, pasture in particular, or supplementing lipids to the diet, represent an efficient mean to modify milk fat composition by decreasing saturated FA and cholesterol, and increasing cis-9,trans-11-CLA and vitamin A. Nutrition therefore constitutes a natural strategy to rapidly modulate milk FA, vitamin A and cholesterol composition, with the overall aim of improving the long-term health of consumers. [ABSTRACT FROM AUTHOR]

Background: Mounting evidence from experimental and animal studies suggests that vitamin A may have a protective effect on melanoma, but the findings on the association of vitamin A intake with risk of melanoma have been inconsistently reported in epidemiologic studies. We attempted to elucidate the association by performing a meta-analysis. Methods: Eligible studies were identified by searching PubMed and EMBASE databases, as well as by reviewing the references of retrieved publications. Summary odds ratios (OR) with corresponding 95% confidence interval (CI) were computed with a random-effects model. Study-specific ORs and 95% CIs for the highest vs. lowest categories of vitamin A intake were pooled. Results: A total of 8 case-control studies and 2 prospective studies comprising 3,328 melanoma cases and 233,295 non-case subjects were included. The summary OR for the highest compared with the lowest intake of total vitamin A, retinol and beta-carotene was 0.86 (95% CI = 0.59–1.25), 0.80 (95% CI = 0.69–0.92) and 0.87 (95%CI = 0.62–1.20), respectively. Significant heterogeneity was observed among studies on vitamin A and beta-carotene intake, but not among studies on retinol intake. Subgroup and sensitivity analyses confirmed these findings. There was no indication of publication bias. Conclusion: Findings from this meta-analysis suggest that intake of retinol, rather than of total vitamin A or beta-carotene, is significantly associated with reduced risk of melanoma. [ABSTRACT FROM AUTHOR]