Maternal vitamin A supplementation and lung function in offspring

Vitamin C supplementation for pregnant smoking women and pulmonary function in their newborn infants: a randomized clinical trial

IMPORTANCE

Maternal smoking during pregnancy adversely affects offspring lung development, with lifelong decreases in pulmonary function and increased asthma risk. In a primate model, vitamin C blocked some of the in-utero effects of nicotine on lung development and offspring pulmonary function.

OBJECTIVE

To determine if newborns of pregnant smokers randomized to receive daily vitamin C would have improved results of pulmonary function tests (PFTs) and decreased wheezing compared with those randomized to placebo.

DESIGN, SETTING, AND PARTICIPANTS

Randomized, double-blind trial conducted in 3 sites in the Pacific Northwest between March 2007 and January 2011. One hundred fifty-nine newborns of randomized pregnant smokers (76 vitamin C treated and 83 placebo treated) and 76 newborns of pregnant nonsmokers were studied with newborn PFTs. Follow-up assessment including wheezing was assessed through age 1 year, and PFTs were performed at age 1 year.

INTERVENTIONS

Pregnant women were randomized to receive vitamin C (500 mg/d) (n = 89) or placebo (n = 90).

MAIN OUTCOMES AND MEASURES

The primary outcome was measurement of newborn pulmonary function (ratio of the time to peak tidal expiratory flow to expiratory time [TPTEF:TE] and passive respiratory compliance per kilogram [Crs/kg]) within 72 hours of age. Secondary outcomes included incidence of wheezing through age 1 year and PFT results at age 1 year. A subgroup of pregnant smokers and nonsmokers had genotyping performed.

RESULTS

Newborns of women randomized to vitamin C (n = 76), compared with those randomized to placebo (n = 83), had improved pulmonary function as measured by TPTEF:TE (0.383 vs 0.345 [adjusted 95% CI for difference, 0.011-0.062]; P = .006) and Crs/kg (1.32 vs 1.20 mL/cm H2O/kg [95% CI, 0.02-0.20]; P = .01). Offspring of women randomized to vitamin C had significantly decreased wheezing through age 1 year (15/70 [21%] vs 31/77 [40%]; relative risk, 0.56 [95% CI, 0.33-0.95]; P = .03). There were no significant differences in the 1-year PFT results between the vitamin C and placebo groups. The effect of maternal smoking on newborn lung function was associated with maternal genotype for the α5 nicotinic receptor (rs16969968) (P < .001 for interaction).

CONCLUSIONS AND RELEVANCE

Supplemental vitamin C taken by pregnant smokers improved newborn PFT results and decreased wheezing through 1 year in the offspring. Vitamin C in pregnant smokers may be an inexpensive and simple approach to decrease the effects of smoking in pregnancy on newborn pulmonary function and respiratory morbidities.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00632476.

Promotion of lung health: NHLBI Workshop on the Primary Prevention of Chronic Lung Diseases

Lung-related research primarily focuses on the etiology and management of diseases. In recent years, interest in primary prevention has grown. However, primary prevention also includes "health promotion" (actions in a population that keep an individual healthy). We encourage more research on population-based (public health) strategies that could not only maximize lung health but also mitigate "normal" age-related declines-not only for spirometry but across multiple measures of lung health. In developing a successful strategy, a "life course" approach is important. Unfortunately, we are unable to achieve the full benefit of this approach until we have better measures of lung health and an improved understanding of the normal trajectory, both over an individual's life span and possibly across generations. We discuss key questions in lung health promotion, with an emphasis on the upper (healthier) end of the distribution of lung functioning and resiliency and briefly summarize the few interventions that have been studied to date. We conclude with suggestions regarding the most promising future research for this important, but largely neglected, area of lung research.

Effects of multimicronutrient supplementation during pregnancy on postnatal growth of children under 5 years of age: a meta-analysis of randomized controlled trials

Background

The beneficial effect of antenatal multiple micronutrients supplementation on infant birth outcomes has been proposed by previous meta-analyses. However, their benefits on postnatal health of children have not been summarized. A meta-analysis of randomized controlled trials was conducted to evaluate the effect of maternal multimicronutrient supplementation on postnatal growth of children under 5 years of age.

Methods

We searched both published and ongoing trials through the PubMed, EMBASE, CENTRAL (OVID platform), Web of Science, BIOSIS Previews, Chinese Science Citation Database, Scopus, ProQuest, ClinicalTrials.gov, Chinese Biomedical Database, and WANFANG database for randomized controlled trials. Reference lists of included studies and relevant reviews were also reviewed for eligible studies. Standard mean difference (SMD) was employed as the index for continuous variables by using fixed effects models. Trend analysis by visual inspection was applied to evaluate the change of mean difference of weight and height between the groups over time.

Results

Nine trials (12 titles) from nine different countries were retrieved for analysis. Pooled results showed that antenatal multimicronutrient supplementation increased child head circumference (SMD = 0.08, 95% CI: 0.00–0.15) compared with supplementation with two micronutrient or less. No evidence was found for the benefits of antenatal multimicronutrient supplementation on weight (P = 0.11), height (P = 0.66), weight-for-age z scores (WAZ) (P = 0.34), height-for-age z scores (HAZ) (P = 0.81) and weight-for-height z scores (WHZ) (P = 0.22). A positive effect was found on chest circumference based on two included studies.

Conclusions

Antenatal multimicronutrient supplementation has a significant positive effect on head circumference of children under 5 years. No impact of the supplementation was found on weight, height, WAZ, HAZ and WHZ.

Prenatal retinoid deficiency leads to airway hyperresponsiveness in adult mice

There is increasing evidence that vitamin A deficiency in utero correlates with abnormal airway smooth muscle (SM) function in postnatal life. The bioactive vitamin A metabolite retinoic acid (RA) is essential for formation of the lung primordium; however, little is known about the impact of early fetal RA deficiency on postnatal lung structure and function. Here, we provide evidence that during murine lung development, endogenous RA has a key role in restricting the airway SM differentiation program during airway formation. Using murine models of pharmacological, genetic, and dietary vitamin A/RA deficiency, we found that disruption of RA signaling during embryonic development consistently resulted in an altered airway SM phenotype with markedly increased expression of SM markers. The aberrant phenotype persisted postnatally regardless of the adult vitamin A status and manifested as structural changes in the bronchial SM and hyperresponsiveness of the airway without evidence of inflammation. Our data reveal a role for endogenous RA signaling in restricting SM differentiation and preventing precocious and excessive SM differentiation when airways are forming.

Gestational vitamin A deficiency: a novel cause of sensorineural hearing loss in the developing world?

Hearing loss is a substantial public health problem with profound social and economic consequences in the developing world. The World Health Organization (WHO) estimates that there are 360 million people living with disabling hearing loss globally, and 80% of these individuals are from low- and middle-income countries. The epidemiology of hearing impairment remains poorly defined in most impoverished societies. Middle ear infections in childhood are a key determinant; however, congenital anomalies may also comprise an important etiology and may arise from gestational malnutrition. While evidence exists that preventable vitamin A deficiency exacerbates the severity of ear infections and, consequently, hearing loss, antenatal vitamin A deficiency during sensitive periods of fetal development may represent an etiologically distinct and virtually unexplored causal pathway. Evidence from multiple animal systems clearly shows that fetal inner ear development requires adequate vitamin A nutriture to proceed normally. Inner ear malformations occur in experimentally imposed maternal vitamin A deficiency in multiple species in a dose-response manner. These anomalies are likely due to the loss of retinoic acid-dependent regulation of both hindbrain development and otic morphogenic processes. Based on in vivo evidence in experimental animals, we hypothesize that preventable gestational vitamin A deficiency, especially during early stages of fetal development, may predispose offspring to inner ear malformations and sensorineural hearing loss. As vitamin A deficiency affects an estimated 20 million pregnant women globally, we hypothesize that, in undernourished settings, routine provision of supplemental vitamin A at the recommended allowance throughout pregnancy may promote normal inner ear development and reduce risk of an as yet unknown fraction of sensorineural hearing loss. If our hypothesis proves correct, gestational vitamin A deficiency would represent a potentially preventable etiology of sensorineural hearing loss of substantial public health significance.

New drug therapies for COPD

Clinical trials with new drugs for chronic obstructive pulmonary disease (COPD) have been performed. Viruses exacerbate COPD and bacteria may play a part in severe COPD; therefore, antibiotic and antiviral approaches have a sound rationale. Antiinflammatory approaches have been studied. Advances in understanding the molecular basis of other processes have resulted in novel drugs to target reactive oxidant species, mucus, proteases, fibrosis, cachexia, and muscle wasting, and accelerated aging. Studies with monoclonal antibodies have been disappointing, highlighting the tendency for infections and malignancies during treatment. Promising future directions are lung regeneration with retinoids and stem cells.

Maternal intake of vitamins A, E and K in pregnancy and child allergic disease: a longitudinal study from the Danish National Birth Cohort

Fat-soluble vitamins A, E and K have been shown to play roles in immunity and inflammation, but studies on child allergic disease have been few and inconsistent. The aim of the present study was to examine the relationship between maternal intake of vitamins A, E and K in mid-pregnancy and child asthma and allergic rhinitis. We used data on 44 594 mother-child pairs from the Danish National Birth Cohort. Maternal intake of fat-soluble vitamins was calculated based on the information from a validated FFQ completed in mid-pregnancy. At 18 months, interviews with the mothers were conducted to evaluate doctor-diagnosed child asthma. At age 7 years, we assessed child asthma and allergic rhinitis using questions from the International Study of Asthma and Allergies in Childhood questionnaire and by national registries on hospital contacts and medication use. Current asthma was defined as asthma diagnosis and wheeze in the past 12 months by maternal report. We calculated multivariable risk ratios and 95 % CI by comparing the highest v. lowest quintile (Q) of maternal vitamin A, E and K intake in relation to child allergic disease outcomes. Maternal total vitamin K intake was directly associated with ever admitted asthma (Q5 v. Q1: 1·23, 95 % CI 1·01, 1·50) and current asthma at 7 years (Q5 v. Q1: 1·30, 95 % CI 0·99, 1·70). Weak inverse associations were present for maternal vitamin A and E intake during pregnancy with child allergic rhinitis. Maternal vitamin K intake during pregnancy may increase the risk of child asthma, and should be explored further on a mechanistic level. Conversely, maternal vitamin A and E intake may protect against child allergic rhinitis.

Molecular determinants of lung development

Development of the pulmonary system is essential for terrestrial life. The molecular pathways that regulate this complex process are beginning to be defined, and such knowledge is critical to our understanding of congenital and acquired lung diseases. A recent workshop was convened by the National Heart, Lung, and Blood Institute to discuss the developmental principles that regulate the formation of the pulmonary system. Emerging evidence suggests that key developmental pathways not only regulate proper formation of the pulmonary system but are also reactivated upon postnatal injury and repair and in the pathogenesis of human lung diseases. Molecular understanding of early lung development has also led to new advances in areas such as generation of lung epithelium from pluripotent stem cells. The workshop was organized into four different topics, including early lung cell fate and morphogenesis, mechanisms of lung cell differentiation, tissue interactions in lung development, and environmental impact on early lung development. Critical points were raised, including the importance of epigenetic regulation of lung gene expression, the dearth of knowledge on important mesenchymal lineages within the lung, and the interaction between the developing pulmonary and cardiovascular system. This manuscript describes the summary of the discussion along with general recommendations to overcome the gaps in knowledge in lung developmental biology.

All-trans retinoic acid modulates ORMDL3 expression via transcriptional regulation

All-trans retinoic acid (ATRA) is an active metabolite of Vitamin A, it shows protective effects on asthma, including maintains airway epithelial integrity, inhibits asthma effector cells differentiation, modulates immune response, et al. However, the promoting effect of ATRA on Th2 response has restricted the clinical application of ATRA in asthma treatment. ORMDL3 is a candidate gene of childhood onset asthma, and high-transcript of ORMDL3 is associated with the development of asthma. Here we show that ATRA increases ORMDL3 production in vitro via inducing PKA-dependent CREB phosphorylation which in turn binds to the CRE element in promoter region of ORMDL3 and initiates ORMDL3 transcription. This finding is in consistent with the previous reports that ATRA could regulate target genes without the presence of retinoic acid response element (RARE) in promoter region but through other signals such as PKA/CREB. Nevertheless, in the present study, the traditional signal pathway of ATRA, retinoic acid receptor (RAR) signal transduction pathway, indirectly modulated ORMDL3 expression. RAR-α agonist (Am-80) increased ORMDL3 production even though there was no RARE in ORMDL3 promoter, introns or 3′-downstream region. Besides, the signal of RAR might differ from that of ATRA since Am-80 failed to induce CREB activation. In conclusion, our data indicate that ATRA facilitates ORMDL3 production probable through PKA/CREB, and this may be a starting point for more detailed mechanism researches on ATRA and asthma.

Prevalence and risk factors of elevated blood pressure, overweight, and dyslipidemia in adolescent and young adults in rural Nepal

BACKGROUND

Chronic disease begins early in life, yet population data are sparse on potential causal factors in children and young adults in South Asia.

METHODS

We assessed risk factors for chronic disease in two population cohorts, aged 9-23 years, in rural Nepal. Assessed variables included short height (less than -2 z), high body mass index (BMI) (z>0.42), waist circumference (WC) >90 cm (male) or 80 cm (female) or age-adjusted child cutoff], high blood pressure (>120/80 mmHg), fasting glucose (≥100 mg/dL), glycosylated hemoglobin (HbA1c) (>7%), blood lipids [triglyceride, high-density lipoprotein cholesterol (HDL-C), and total cholesterol], diet, smoking, alcohol, and socioeconomic status (SES) factors.

RESULTS

The population was stunted (46%) and few were overweight (∼2%-4% with high BMI or WC). Twelve percent had high blood pressure. Plasma hypertriglyceridemia (≥150 mg/dL) affected ∼8.5%, and 78% had low HDL-C concentrations <40 mg/dL (male) or <50 mg/dL (female)], while few (≤3%) had elevated total cholesterol (≥180 mg/dL), glucose, and HbA1c. Females were at higher risk than males for high blood pressure [odds ratio (OR) 1.9; 95% confidence interval (CI) 1.6-2.3] and overweight (4.2; 3.0-5.8), but had lower risk of dyslipidemia (0.7; 0.6-0.9). Ethnic plains Madheshi were less likely to be overweight (0.3; 0.2-0.4), but had greater risk of dyslipidemia (1.4; 1.1-1.7) versus those of Hill origin. Some dietary factors were significantly associated with high blood pressure or dyslipidemia, but not overweight.

CONCLUSIONS

Dyslipidemia and high blood pressure are emerging health concerns among young adults in rural Nepal.

Vitamin A supplementation in extremely low-birth-weight infants: subgroup analysis in small-for-gestational-age infants

OBJECTIVE

Preterm infants with intrauterine growth restriction are at increased risk of respiratory distress syndrome and bronchopulmonary dysplasia (BPD). A randomized clinical trial by the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) Neonatal Research Network demonstrated that vitamin A supplementation in extremely low-birth-weight (ELBW) preterm infants requiring early respiratory support decreased the risk of developing BPD.

STUDY DESIGN

A subgroup analysis of small-for-gestational-age (SGA) infants from the original NICHD trial was performed to test the hypothesis that in infants requiring early respiratory support, vitamin A supplementation decreases the relative risk of BPD or death in premature SGA infants to a greater extent than in gestational age-equivalent vitamin A-treated appropriate-for-gestational-age (AGA) infants.

RESULTS

Although vitamin A supplementation significantly increased serum retinol concentrations in AGA ELBW infants (median [5th percentile, 95th percentile]: 16.3 [-7.0, 68.8] versus 2.4 [-13.9, 55.1]; p < 0.001), no increases were noted in SGA ELBW infants.

CONCLUSIONS

Given the limited power of this analysis due to a low number of SGA infants, these data did not provide evidence to support the hypothesis that vitamin A supplementation in preterm SGA infants requiring early respiratory support decreases the relative risk of BPD or death as compared with preterm AGA infants.

Diet and vitamin D as risk factors for lung impairment and COPD

Epidemiologic and observational studies have shown an association between increased intakes of certain micronutrients and higher levels of lung function and health. The National Health and Nutrition Examination Surveys of the U.S. population have demonstrated repeatedly that increased intakes or serum levels of some micronutrients, including the vitamins E, D, C, and A, and carotenes are associated positively with forced expiratory volume in 1 second (FEV1). These findings are complemented by other observational studies, including the MORGEN study as well as the Seven Countries Study, both of which found micronutrient status had positive correlations with pulmonary function. In addition, epidemiologic studies have demonstrated that dietary intake patterns with increased intakes of fruit, vegetables, fish, vitamin E, and whole grains have been associated with a decreased development of chronic obstructive pulmonary disease (COPD) in smokers and nonsmokers, higher levels of FEV1, and decreased long-term COPD mortality. Diets high in refined food have been associated with accelerated longitudinal decline in FEV1 over 5 years. Taken together, these results suggest that micronutrient status may impact lung function, and that nutrition interventions could be a useful tool in a public health campaign aimed at the prevention of lung disease. Future research should focus on the effect of nutrition interventions on the natural history of lung disease.

Early lung development: lifelong effect on respiratory health and disease

Interest in the contribution of changes in lung development during early life to subsequent respiratory morbidity is increasing. Most evidence of an association between adverse intrauterine factors and structural effects on the developing lung is from animal studies. Such evidence has been augmented by epidemiological studies showing associations between insults to the developing lung during prenatal and early postnatal life and adult respiratory morbidity or reduced lung function, and by physiological studies that have elucidated mechanisms underlying these associations. The true effect of early insults on subsequent respiratory morbidity can be understood only if the many prenatal and postnatal factors that can affect lung development are taken into account. Adverse factors affecting lung development during fetal life and early childhood reduce the attainment of maximum lung function and accelerate lung function decline in adulthood, initiating or worsening morbidity in susceptible individuals. In this Review, we focus on factors that adversely affect lung development in utero and during the first 5 years after birth, thereby predisposing individuals to reduced lung function and increased respiratory morbidity throughout life. We focus particularly on asthma and COPD.

Alendronate attenuates eosinophilic airway inflammation associated with suppression of Th2 cytokines, Th17 cytokines, and eotaxin-2

Bisphosphonates (BPs) have been widely used to treat osteoporosis. They act by inhibiting farnesyl diphosphate synthase in the mevalonate pathway. This resembles the action of statins, whose immune-modulating effect has recently been highlighted. In contrast, the effect of BPs on immune responses has not been elucidated well. In this study, we examined the effect of alendronate (ALN), a nitrogen-containing BP, on allergic airway inflammation in a mouse model. BALB/c mice were sensitized twice with OVA and challenged three times with nebulized OVA to induce eosinophilic airway inflammation. ALN was administered by an intragastric tube before each inhalation. ALN strongly suppressed airway eosinophilia and Th2, as well as Th17 cytokine production in the lung. ALN also attenuated eotaxin-2 production in the lung. Immunohistochemistry demonstrated that the major cell source of eotaxin-2 was peribronchial/perivascular macrophages, and flow cytometrical studies confirmed that ALN decreased eotaxin-2 expression in these macrophages. Furthermore, ALN attenuated eotaxin-2 production from mouse pleural macrophages and human monocyte/macrophage-like THP-1 cells in vitro. These results suggest that ALN suppressed Ag-induced airway responses in the mouse model. The suppression of eotaxin-2 production from macrophages appears to be one of ALN's immunomodulatory effects, whereas the mechanism by which ALN suppressed Th2 and Th17 responses could not be fully elucidated in this study. Although a clinical study should be conducted, ALN could be a novel therapeutic option for asthma.

Diet and asthma: vitamins and methyl donors

Diet changes can partly explain the high burden of asthma in industrialised nations. Findings from experimental studies have stimulated many observational studies of the association between vitamins (A, C, D, and E) or nutrients acting as methyl donors (folate, vitamin B12, and choline) and asthma. However, observational studies are susceptible to several sources of bias; well conducted randomised controlled trials (RCTs) are the gold standard to establish whether diet has an effect on asthma. Evidence from observational studies and a few RCTs strongly justifies ongoing and future RCTs in three areas: vitamin D for the prevention or treatment of asthma, choline supplementation as adjuvant treatment for asthma, and vitamin E to prevent the detrimental effects of air pollution in patients with asthma. At present, insufficient evidence exists to recommend supplementation with any vitamin or nutrient acting as a methyl donor to prevent or treat asthma.

Healthy Foods North improves diet among Inuit and Inuvialuit women of childbearing age in Arctic Canada

BACKGROUND

Healthy Foods North (HFN) is a community-based intervention designed to promote a healthy diet and lifestyle of Inuit and Inuvialuit populations in Arctic Canada. The objective of the present study was to determine the effects of HFN on the nutrient intake of women of childbearing age.

METHODS

Six communities in Nunavut (n = 3) and the Northwest Territories (n = 3) were selected for programme implementation; four received a 12-month intervention and two served as controls. Quantitative food frequency questionnaires were used to assess dietary intake at baseline and 1 year post-intervention. Among women participants aged 19-44 years (n = 136), 79 were exposed to the intervention and 57 were not. Mean daily energy and nutrient intake and density were determined. Dietary adequacy was assessed by comparing the women's daily nutrient intakes with dietary reference intakes (DRI).

RESULTS

Main outcomes were the pre- to post-intervention changes between intervention and control groups for energy and selected nutrient intakes, nutrient density and dietary adequacy. Among the participants, the intervention had a beneficial effect on vitamin A and D intake. The percentage of individuals with nutrient intakes below the DRI increased from pre- to post-intervention for vitamin A and D in the control group but only for vitamin A in the intervention group. The programme did not have a significant impact on calorie, sugar, or fat consumption.

CONCLUSIONS

The HFN programme is effective in mitigating some of the negative impacts of the nutrition transition on dietary adequacy among Inuit and Inuvialuit women of childbearing age.

Early life influences on the development of chronic obstructive pulmonary disease

There is increasing evidence that chronic obstructive pulmonary disease (COPD) is not simply a disease of old age that is largely restricted to heavy smokers, but may be associated with insults to the developing lung during foetal life and the first few years of postnatal life, when lung growth and development are rapid. A better understanding of the long-term effects of early life factors, such as intrauterine growth restriction, prenatal and postnatal exposure to tobacco smoke and other pollutants, preterm delivery and childhood respiratory illnesses, on the subsequent development of chronic respiratory disease is imperative if appropriate preventive and management strategies to reduce the burden of COPD are to be developed. The extent to which insults to the developing lung are associated with increased risk of COPD in later life depends on the underlying cause, timing and severity of such derangements. Suboptimal conditions in utero result in aberrations of lung development such that affected individuals are born with reduced lung function, which tends to remain diminished throughout life, thereby increasing the risk both of wheezing disorders during childhood and subsequent COPD in genetically susceptible individuals. If the current trend towards the ever-increasing incidence of COPD is to be reversed, it is essential to minimize risks to the developing lung by improvements in antenatal and neonatal care, and to reduce prenatal and postnatal exposures to environmental pollutants, including passive tobacco smoke. Furthermore, adult physicians need to recognize that lung disease is potentially associated with early life insults and provide better education regarding diet, exercise and avoidance of smoking to preserve precious reserves of lung function in susceptible adults. This review focuses on factors that adversely influence lung development in utero and during the first 5 years of life, thereby predisposing to subsequent COPD.

Cognitive and motor skills in school-aged children following maternal vitamin A supplementation during pregnancy in rural Nepal: a follow-up of a placebo-controlled, randomised cohort

OBJECTIVE

To determine the effects of maternal vitamin A supplementation from preconception through postpartum on cognitive and motor development of children at 10-13 years of age in rural Nepal.

DESIGN

Follow-up assessment of children born to women randomly assigned by a village to receive either supplemental vitamin A (7000 µg retinol equivalents) or placebo weekly during a continuous 3.5-year period from 1994-1997. The participants came from 12 wards, a subset of 270 wards in the original trial. Trained staff tested children for cognition by the Universal Nonverbal Intelligence Test (UNIT) and motor ability using four subtests from the Movement Assessment Battery for Children (MABC). Data on schooling, home environment and nutritional and socioeconomic status were also collected.

SETTING

Southern plains district of Sarlahi, Nepal.

PARTICIPANTS

390 Nepalese children 10-13 years of age.

MAIN OUTCOME MEASURES

Raw scores on UNIT and square-root transformed scores on an abridged version of the MABC tests, expressed as cluster-summarised (mean±SD) values to account for the design of the original trial.

RESULTS

There were no differences in UNIT (79.61±5.99 vs 80.69±6.71) or MABC (2.64±0.07 vs 2.49±0.09) test scores in children whose mothers were exposed to vitamin A vs placebo (mean differences: -1.07, 95% CI -7.10 to 9.26, p=0.78; 0.15, 95% CI 0.43 to -0.08, p=0.15), respectively. More children in the placebo group had repeated a grade in school (28% of placebo vs 16.7% of vitamin A, p=0.01).

CONCLUSIONS

Preconceptional to postpartum maternal vitamin A supplementation, in an undernourished setting, does not improve cognition or motor development at ages 10-13 years.

Vitamin A deficiency alters airway resistance in children with acute upper respiratory infection

OBJECTIVE

To assess whether vitamin A deficiency alters the recovery of total respiratory resistance (TRR) following acute upper respiratory tract infection (URI).

METHODS

This is a case control study of children, age 4-6 years and grouped as: URI, (n = 74), URI and wheezing, (URI-wheezing, n = 52), and healthy controls (n = 51). Vitamin A and total respiratory resistance (TRR) were assessed using the modified relative dose response (MRDR) and forced oscillometry, respectively.

RESULTS

Children with URI and URI-wheezing had lower retinol, 32.4 ± 13.12 and 18.3 ± 6.83 µg/dl respectively, compared to controls, 56.9 ± 29.82 µg/dl (ANOVA, P < 0.001). The MRDR was elevated in children in the URI or URI-wheezing groups 0.066 ± 0.045 and 0.021 ± 0.021, respectively, compared to controls 0.007 ± 0.006 (ANOVA, P < 0.0001). The TRR in the URI and URI-wheezing groups differed from controls. During convalescence, the TRR failed to decline in the URI-group only when the MRDR was >0.06. In the URI-wheezing group, TRR declined independently of retinol and MRDR.

CONCLUSION

Vitamin A contributes to preservation of airway function during and in recovery after upper respiratory infection in children.

Dietary vitamin A intake below the recommended daily intake during pregnancy and the risk of congenital diaphragmatic hernia in the offspring

BACKGROUND

Vitamin A has been related to the etiology of congenital diaphragmatic hernia (CDH). We performed a case-control study to investigate whether maternal dietary vitamin A intake is related to CDH in the offspring.

METHODS

Thirty-one pregnancies diagnosed with CDH and 46 control pregnancies were included during the study. After CDH diagnosis and inclusion of controls by risk set sampling, maternal vitamin A intake was investigated with a food frequency questionnaire. Serum retinol and retinol-binding protein were determined. Univariable and multivariable logistic regression models were used to calculate risk estimates with adjustment for potential confounders.

RESULTS

We found no significant differences in the overall nutrient and vitamin A intake between case and control mothers. After stratification in body mass index (BMI) categories, case mothers with normal weight showed a lower energy adjusted vitamin A intake (685 vs. 843 μg retinol activity equivalents [RAEs] / day; p = 0.04) and a slightly lower serum retinol (1.58 vs. 1.67 μmol/L; p = 0.08) than control mothers. Vitamin A intake <800 μg retinol activity equivalents (recommended daily intake) in normal weight mothers was associated with a significantly increased CDH risk (odds ratio [OR], 7.2; 95% confidence interval [CI], 1.5-34.4; p = 0.01). Associations were not significantly different in underweight and overweight mothers.

CONCLUSIONS

In normal-weight mothers, dietary vitamin A intake during pregnancy below the recommended daily intake is significantly associated with an increased risk of a child with CDH. This finding supports the retinoid hypothesis in human CDH, but warrants further investigation in larger study populations. Birth Defects Research (Part A), 2013. © 2013 Wiley Periodicals, Inc.

Retinoic acid rescues alveolar hypoplasia in the calorie-restricted developing rat lung

Infants born with intrauterine growth retardation (IUGR) are at increased risk of adverse pulmonary outcomes at birth, including meconium aspiration and persistent pulmonary hypertension. Preterm infants with IUGR are at especially high risk of developing bronchopulmonary dysplasia (BPD), a disease hallmarked by alveolar hypoplasia. Although vitamin A supplementation has been shown to decrease the incidence of BPD or death in preterm very low birth weight infants, its potential to reduce BPD or death in preterm infants with IUGR remains unknown. We used a well-characterized rat model of caloric restriction to mimic IUGR and determine the impact of IUGR on lung development. We hypothesized that retinoic acid treatment would preserve alveolar formation through increases in key signaling molecules of the retinoic acid signaling pathway. Our results showed that alveolar hypoplasia caused by caloric restriction can be reversed with refeeding, and that retinoic acid prevents the alveolar hypoplasia coincident with the increased expression of elastin and retinoic acid receptor-α and decreased transforming growth factor-β activity in developing rat lungs. These findings suggest that alveolar hypoplasia attributable to caloric restriction is reversible, and raises the possibility that retinoic acid therapy may prove a useful strategy to prevent adverse pulmonary sequelae such as BPD in preterm infants with IUGR.

Intrapleural chemotherapy improves the survival of non-small cell lung cancer patients with positive pleural lavage cytology

PURPOSE

Information regarding the treatment of pleural lavage cytology (PLC)-positive patients is still limited. This study evaluated the efficacy of intrapleural chemotherapy (IPC) in PLC-positive patients.

METHODS

Three hundred eighty-six of the 567 lung cancer patients who underwent surgery had undergone PLC after thoracotomy, following by a complete resection were evaluated. IPC was performed after surgery, and cisplatin or adriamycin was injected intrapleurally through the thoracic tube.

RESULTS

The pathological diagnosis showed that 17 patients (4.4 %) were positive for (or suspected to have) malignancy in their PLC. The univariate and multivariate analysis showed that only pleural invasion was a significant predictor of a PLC-positive status. The 5-year overall survival in PLC-positive patients was 38 % and that in PLC-negative patients was 84 %. Both the univariate (p < 0.01) and multivariate (p = 0.045) analyses showed that the status of PLC was significantly associated with the overall survival. Eight of the 17 PLC-positive patients underwent IPC. The 2-year OS rate in the patients treated with IPC was 88 % and that of those without IPC was 44 (p = 0.04).

CONCLUSION

IPC improved the postoperative survival in PLC-positive NSCLC patients, and a further prospective evaluation regarding this therapy is warranted.

Prenatal iodine deficiency results in structurally and functionally immature lungs in neonatal rats

Maternal hypothyroidism affects postnatal lung structure. High prevalence of hypothyroxinemia (low T4, normal T3) in iodine-deficient pregnant women and associated risk for neuropsychological development along with high infant/neonatal mortality ascribed to respiratory distress prompted us to study the effects of maternal hypothyroxinemia on postnatal lung development. Female Sprague Dawley rats were given a low-iodine diet (LID) with 1% KClO4in drinking water for 10 days, to minimize thyroid hormone differences. Half of these rats were continued on iodine-deficient diet; ID (LID with 0.005% KClO4) for 3 mo, whereas the rest were switched to an iodine-sufficient diet; IS [LID + potassium iodide (10 μg iodine/20 g of diet + normal drinking water)]. Pups born to ID mothers were compared with age-matched pups from IS mothers at postnatal days 8 (P8) and 16 (P16) ( n = 6–8/group). ID pups had normal circulating T3 but significantly low T4 levels ( P < 0.05) and concomitantly approximately sixfold higher thyroid hormone receptor-β mRNA in alveolar epithelium. Lung histology revealed larger and irregularly shaped alveoli in ID pups relative to controls. Lung function was assessed at P16 using a double-chambered plethysmograph and observed reduced tidal volume, peak inspiratory and expiratory flow, and dynamic lung compliance in ID pups compared with IS pups. Significant lowering of surfactant protein (SP)-B and SP-C mRNA and protein found in ID pups at P16. ID pups had 16-fold lower matrix metalloproteinase-9 mRNA levels in their alveolar epithelium. In addition, mRNA levels of thyroid transcription factor-1 and SP-D were significantly higher (3-fold) compared with IS pups. At P16, significantly lower levels of SP-B and SP-C found in ID pups may be responsible for immature lung development and reduced lung compliance. Our data suggest that maternal hypothyroxinemia may result in the development of immature lungs that, through respiratory distress, could contribute to the observed high infant mortality in ID neonates.

Vitamin A supply to mothers and children: challenges and opportunities

PURPOSE OF REVIEW

Although we are close to the centennial of the discovery of vitamin A, our understanding of the functions of this major micronutrient is still evolving. Given its major role in fetal development, growth, vision, immunity and survival, a subtle balance is required between adequate intake to avoid deficiency and excessive intake to avoid toxicity, both in low income and industrialized countries.

RECENT FINDINGS

This review highlights the potential impact of vitamin A supplementation (VAS) in mothers and children suffering from vitamin A deficiency (VAD) on mortality and morbidities, and warns against the increasingly frequent use of bariatric surgery especially to treat severely obese childbearing women, which is known to alter vitamin A status.

SUMMARY

Despite massive vitamin A supplementation public health policies in developing countries, the burden of VAD is still common and efforts should be maintained to better target populations at risk, and to develop alternative strategies for supplementation based on sustainable and integrated approaches. In industrialized countries, VAD due to insufficient intake is scarce, but it may surprisingly occur due to the decreased absorption of lipids following antiobesity treatments. Specific approaches should be developed to better monitor and supplement obese childbearing women who have undergone bariatric surgery.

Bilateral assessment of functional tasks for robot-assisted therapy applications

This article presents a novel evaluation system along with methods to evaluate bilateral coordination of arm function on activities of daily living tasks before and after robot-assisted therapy. An affordable bilateral assessment system (BiAS) consisting of two mini-passive measuring units modeled as three degree of freedom robots is described. The process for evaluating functional tasks using the BiAS is presented and we demonstrate its ability to measure wrist kinematic trajectories. Three metrics, phase difference, movement overlap, and task completion time, are used to evaluate the BiAS system on a bilateral symmetric (bi-drink) and a bilateral asymmetric (bi-pour) functional task. Wrist position and velocity trajectories are evaluated using these metrics to provide insight into temporal and spatial bilateral deficits after stroke. The BiAS system quantified movements of the wrists during functional tasks and detected differences in impaired and unimpaired arm movements. Case studies showed that stroke patients compared to healthy subjects move slower and are less likely to use their arm simultaneously even when the functional task requires simultaneous movement. After robot-assisted therapy, interlimb coordination spatial deficits moved toward normal coordination on functional tasks.

Supplementation with vitamin A early in life and subsequent risk of asthma

Animal models suggest that vitamin A deficiency affects lung development adversely and promotes airway hyperresponsiveness, and may predispose to an increased risk of asthma. We examined the long-term effects of vitamin A supplementation early in life on later asthma risk. In 2006-2008, we revisited participants from two cohorts in rural Nepal who were enrolled in randomised trials of vitamin A supplementation. The first cohort received vitamin A or placebo for <16 months during their pre-school years (1989-1991). The second cohort was born to mothers who received vitamin A, β-carotene or placebo before, during and after pregnancy (1994-1997). At follow-up, we asked about asthma symptoms and performed spirometry. Out of 6,421 subjects eligible to participate, 5,430 (85%) responded to our respiratory survey. Wheezing prevalence during the previous year was 4.8% in participants aged 9-13 yrs and 6.6% in participants aged 14-23 yrs. We found no differences between the vitamin A supplemented and placebo groups from either trial in the prevalence of lifetime or current asthma and wheeze or in spirometric indices of obstruction (p ≥ 0.12 for all comparisons). Vitamin A supplementation early in life was not associated with a decreased risk of asthma in an area with chronic vitamin A deficiency.

Is a regenerative approach viable for the treatment of COPD?

Degenerative lung diseases such as chronic obstructive pulmonary disease (COPD) are common with huge worldwide morbidity. Anti-inflammatory drug development strategies have proved disappointing and current treatment is aimed at symptomatic relief. Only lung transplantation with all its attendant difficulties offers hope of cure and the outlook for affected patients is bleak. Lung regeneration therapies aim to reverse the structural and functional deficits in COPD either by delivery of exogenous lung cells to replace lost tissue, delivery of exogenous stem cells to induce a local paracrine effect probably through an anti-inflammatory action or by the administration of small molecules to stimulate the endogenous regenerative ability of lung cells. In animal models of emphysema and disrupted alveolar development each of these strategies has shown some success but there are potential tumour-inducing dangers with a cellular approach. Small molecules such as all-trans retinoic acid have been successful in animal models although the mechanism is not completely understood. There are currently two Pharma-sponsored trials in progress concerning patients with COPD, one of a specific retinoic acid receptor gamma agonist and another using mesenchymal stem cells.

Vitamin A in reproduction and development

The requirement for vitamin A in reproduction was first recognized in the early 1900's, and its importance in the eyes of developing embryos was realized shortly after. A greater understanding of the large number of developmental processes that require vitamin A emerged first from nutritional deficiency studies in rat embryos, and later from genetic studies in mice. It is now generally believed that all-trans retinoic acid (RA) is the form of vitamin A that supports both male and female reproduction as well as embryonic development. This conclusion is based on the ability to reverse most reproductive and developmental blocks found in vitamin A deficiency induced either by nutritional or genetic means with RA, and the ability to recapitulate the majority of embryonic defects in retinoic acid receptor compound null mutants. The activity of the catabolic CYP26 enzymes in determining what tissues have access to RA has emerged as a key regulatory mechanism, and helps to explain why exogenous RA can rescue many vitamin A deficiency defects. In severely vitamin A-deficient (VAD) female rats, reproduction fails prior to implantation, whereas in VAD pregnant rats given small amounts of carotene or supported on limiting quantities of RA early in organogenesis, embryos form but show a collection of defects called the vitamin A deficiency syndrome or late vitamin A deficiency. Vitamin A is also essential for the maintenance of the male genital tract and spermatogenesis. Recent studies show that vitamin A participates in a signaling mechanism to initiate meiosis in the female gonad during embryogenesis, and in the male gonad postnatally. Both nutritional and genetic approaches are being used to elucidate the vitamin A-dependent pathways upon which these processes depend.

Vitamin A supplementation during pregnancy for maternal and newborn outcomes

BACKGROUND

The World Health Organization recommends routine vitamin A supplementation during pregnancy or lactation in areas with endemic vitamin A deficiency (where night blindness occurs), based on the expectation that supplementation will improve maternal and newborn outcomes including mortality, morbidity and prevention of anaemia or infection.  

OBJECTIVES

To review the effects of supplementation of vitamin A, or one of its derivatives, during pregnancy, alone or in combination with other vitamins and micronutrients, on maternal and newborn clinical outcomes.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (15 July 2010).

SELECTION CRITERIA

All randomised or quasi-randomised trials, including cluster-randomised trials, evaluating the effect of vitamin A supplementation in pregnant women.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed all studies for inclusion and resolved any disagreement through discussion with a third person. We used pre-prepared data extraction sheets.

MAIN RESULTS

We examined 88 reports of 31 trials, published between 1931 and 2010, for inclusion in this review. We included 16 trials, excluded 14, and one is awaiting assessment.Overall when trial results are pooled, Vitamin A supplementation does not affect the risk of maternal mortality (risk ratio (RR) 0.78, 95% confidence interval (CI) 0.55 to 1.10, 3 studies, Nepal, Ghana,UK ), perinatal mortality, neonatal mortality, stillbirth, neonatal anaemia, preterm birth or the risk of having a low birthweight baby. Vitamin A supplementation reduces the risk of maternal night blindness (risk ratio (RR) 0.70, 95% CI 0.60 to 0.82, 1 trial Nepal). In vitamin A deficient populations and HIV-positive women, vitamin A supplementation reduces maternal anaemia (risk ratio (RR) 0.64, 95% confidence interval (CI) 0.43 to 0.94, 3 trials, Indonesia, Nepal,Tanzania ). There is evidence that vitamin A supplements may reduce maternal clinical infection (RR 0.37, 95% CI 0.18 to 0.77, 3 trials, South Africa, Nepal and UK).In HIV-positive women vitamin A supplementation given with other micronutrients was associated with fewer low birthweight babies (< 2.5 kg) in the supplemented group in one study (RR 0.67, CI 0.47 to 0.96).

AUTHORS' CONCLUSIONS

The pooled results of two large trials in Nepal and Ghana (with almost 95,000 women) do not currently suggest a role for antenatal vitamin A supplementation to reduce maternal or perinatal mortality. However the populations studied were probably different with regard to baseline vitamin A status and there were problems with follow-up of women. There is good evidence that antenatal vitamin A supplementation reduces maternal anaemia for women who live in areas where vitamin A deficiency is common or who are HIV-positive. In addition the available evidence suggests a reduction in maternal infection, but these data are not of a high quality.