The evaluation of serum leptin level and other hormonal parameters in children with severe malnutrition

A cluster-randomized trial of water, sanitation, handwashing and nutritional interventions on stress and epigenetic programming

A regulated stress response is essential for healthy child growth and development trajectories. We conducted a cluster-randomized trial in rural Bangladesh (funded by the Bill & Melinda Gates Foundation, ClinicalTrials.gov NCT01590095) to assess the effects of an integrated nutritional, water, sanitation, and handwashing intervention on child health. We previously reported on the primary outcomes of the trial, linear growth and caregiver-reported diarrhea. Here, we assessed additional prespecified outcomes: physiological stress response, oxidative stress, and DNA methylation (N = 759, ages 1-2 years). Eight neighboring pregnant women were grouped into a study cluster. Eight geographically adjacent clusters were block-randomized into the control or the combined nutrition, water, sanitation, and handwashing (N + WSH) intervention group (receiving nutritional counseling and lipid-based nutrient supplements, chlorinated drinking water, upgraded sanitation, and handwashing with soap). Participants and data collectors were not masked, but analyses were masked. There were 358 children (68 clusters) in the control group and 401 children (63 clusters) in the intervention group. We measured four F2-isoprostanes isomers (iPF(2α)-III; 2,3-dinor-iPF(2α)-III; iPF(2α)-VI; 8,12-iso-iPF(2α)-VI), salivary alpha-amylase and cortisol, and methylation of the glucocorticoid receptor (NR3C1) exon 1F promoter including the NGFI-A binding site. Compared with control, the N + WSH group had lower concentrations of F2-isoprostanes isomers (differences ranging from -0.16 to -0.19 log ng/mg of creatinine, P < 0.01), elevated post-stressor cortisol (0.24 log µg/dl; P < 0.01), higher cortisol residualized gain scores (0.06 µg/dl; P = 0.023), and decreased methylation of the NGFI-A binding site (-0.04; P = 0.037). The N + WSH intervention enhanced adaptive responses of the physiological stress system in early childhood.

The Effects of Nutrition on Linear Growth

Linear growth is a complex process and is considered one of the best indicators of children’s well-being and health. Genetics, epigenetics and environment (mainly stress and availability of nutrients) are the main regulators of growth. Nutrition exerts its effects on growth throughout the course of life with different, not completely understood mechanisms. Cells have a sophisticated sensing system, which allows growth processes to occur in the presence of an adequate nutrient availability. Most of the nutritional influence on growth is mediated by hormonal signals, in turn sensitive to nutritional cues. Both macro- and micro-nutrients are required for normal growth, as demonstrated by the impairment of growth occurring when their intake is insufficient. Clinical conditions characterized by abnormal nutritional status, including obesity and eating disorders, are associated with alterations of growth pattern, confirming the tight link between growth and nutrition. The precise molecular mechanisms connecting nutrition to linear growth are far from being fully understood and further studies are required. A better understanding of the interplay between nutrients and the endocrine system will allow one to develop more appropriate and effective nutritional interventions for optimizing child growth.

Leptin levels in children with malnutrition

OBJECTIVE

This study aimed at comparing serum levels of leptin in children with malnutrition and good nutritional status.

METHOD

This cross-sectional study included 41 participants consisting of 31 malnutrition, 10 well-nourished children aged between 36 and 60 months. Demographic data of participants were obtained utilizing a questionnaire. Nutritional status was determined by calculating the Z-score of body weight for age, height for age, and body weight for height indices using the WHO classification. Leptin levels were determined by ELISA (Enzyme-Linked Immunosorbent Assay) method.

RESULTS

Median serum leptin level for malnutrition children were found to be lower, i.e., 9.23 (6.02-197.2) ng/mL compared to well-nourished children 30.95 (6.02-89.36) ng/mL.

CONCLUSION

Serum leptin levels can be used as indicators to assess nutritional status.

Malnutrition Aggravates Alterations Observed in the Gut Structure and Immune Response of Mice Infected with Leishmania infantum

Malnutrition is a risk factor for developing visceral leishmaniasis and its severe forms. Our group demonstrated that malnourished animals infected with Leishmania infantum had severe atrophies in lymphoid organs and T cell subpopulations as well as altered levels of thymic and splenic chemotactic factors, all of which resulted in dysfunctional lymphoid microenvironments that promoted parasite proliferation. Here, we hypothesize that malnutrition preceding parasite infection leads to structural and immunological changes in the gut mucosae, resulting in a failure in the immune response sensed in the intestine. To evaluate this, we analyzed the immunopathological events resulting from protein malnutrition in the guts of BALB/c mice infected with L. infantum. We observed lymphocytic/lymphoplasmacytic inflammatory infiltrates and lymphoid hyperplasia in the duodenum of well-nourished-infected mice; such alterations were worsened when malnutrition preceded infection. Parasite infection induced a significant increase of duodenal immunoglobulin A (IgA) of well-nourished animals, but those levels were significantly decreased in malnourished-infected mice. In addition, increased levels of Th17-related cytokines in duodenums of malnourished animals supported local inflammation. Together, our results suggest that the gut plays a potential role in responses to L. infantum infection—and that such responses are impaired in malnourished individuals.

Influence of enhanced nutrition and psychosocial stimulation in early childhood on cognitive functioning and psychological well-being in Guatemalan adults

Rationale

Early-life nutrition interventions in low and middle-income countries have demonstrated long-term benefits on cognitive skills, however, their influence on socioemotional outcomes has not been fully explored. Moreover, the mediating processes through which nutrition intervention effects operate and are maintained over time are understudied.

Methods

We followed-up a cohort of Guatemalan adults who participated as children in a community randomized food-supplementation trial. We examined associations of exposure to nutritional supplementation from conception to age 2 years with executive function (measured using three sub-tests of the NIH Toolbox Cognition Battery) and psychological well-being (measured using two sub-scales of the NIH Toolbox Emotion Battery) at ages 40–57 years (n = 1268). We used structural equation modeling to investigate the mediating role of psychosocial stimulation (measured in childhood using parent reports and ratings of home environments), cognitive ability (measured at ages 26–42 years using standardized tests), and executive function on the association of early-life exposure to nutritional supplementation with adult psychological well-being (n = 1640).

Results

We found positive but inconsistent associations of nutritional supplementation in childhood with executive function and psychological well-being in adulthood. Psychosocial stimulation, cognitive ability, and executive function did not mediate the association of early-life nutritional supplementation with adult psychological well-being. We found strong and positive associations of psychosocial stimulation in childhood with cognitive ability, executive function, and psychological well-being in adulthood. Moreover, we observed no interaction of exposure to nutritional supplementation and psychosocial stimulation in childhood with cognitive and psychological well-being outcomes in adulthood.

Conclusion

Our findings suggest that childhood nutrition interventions have long-lasting effects on cognitive ability and psychological well-being outcomes.

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We assess the influence of early-life nutrition on neurodevelopmental outcomes.

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We use a theoretical approach to examine mediators of the association.

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We found no mediators of the association of early-life nutrition with adult psychological well-being.

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Psychosocial stimulation is strongly associated with neurodevelopmental outcomes.

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Improved child nutrition is positively associated with adult psychological well-being.

An SPR imaging immunosensor for leptin determination in blood plasma

Leptin is a hormone that has a fundamental role in the regulation of feeding and energy balance. A developed specific SPRi immunosensor for leptin may be a new tool for leptin determination in blood plasma. The immunosensor consists of rabbit anti-leptin antibody immobilized on a gold chip via cysteamine linker, using the EDC/NHS protocol. Non-fluidic array SPRi is used for analytical signal formation. Under optimized conditions, the linear response range of the immunosensor covers concentrations from 0.23 to 5 ng mL^-1. The LOD of the immunosensor is 0.07 ng mL^-1, and the LOQ is 0.23 ng mL^-1. The precision of measurement depends on leptin concentration, and is between 9.1% and 2.2%. Recoveries of the leptin spike are between 97% and 110%. The immunosensor and related analytical method were validated by parallel determination of leptin in series of plasma from children suffering from malnutrition and a control group, using Enzyme-Linked Immunosorbent Assay (ELISA) and SPRi. Pearson's correlation coefficient was equal to 0.991. The developed immunosensor and related method are more direct, faster and much simpler than ELISA.

Systematic Review of Tools and Methods to Measure Appetite in Undernourished Children in the Context of Low- and Middle-Income Countries

Child undernutrition has multifactorial causes, ranging from food insecurity to etiologies refractory to conventional nutritional approaches, such as infections, environmental enteric dysfunction, and other conditions that lead to systemic inflammation. Poor appetite may be an important symptom of these causes and may be a useful marker of an undernourished child's ability to recover. We conducted a systematic review to characterize the methods and tools to measure appetite among children <5 y old in low- and middle-income countries. A systematic search of 8 databases identified 23 eligible studies published since 1995. Thirteen described methods based on direct feeding observation or quantification of nutrient intake from caregiver report, 16 described tools that assessed caregiver perceptions of appetite, and 6 reported assessments in both categories. Four studies that gauged caregiver perceptions assessed multiple appetite domains, whereas 12 assessed 1 domain-often with a single question. Only 6 studies reported validation processes, the most common of which compared an observed test meal with daily energy intake. No studies reported the use of a method or tool that was validated in multiple cultural or linguistic contexts. Although dietary intake measures and observed feeding tests have shown validity in some contexts, they are resource intensive. Subjective caregiver questionnaires may offer a more efficient appetite evaluation method, but they have been evaluated less consistently. A rigorously developed and validated tool to rapidly assess child appetite is needed and could be best addressed by a questionnaire that leverages the multiple domains of appetite. The application of interventions that target causes of undernutrition that are not amenable to food-based interventions in clinical or research contexts could be facilitated by an efficient appetite screening tool to identify appetite-related causes of undernutrition and to monitor children's response to such interventions.

Hormonal Correlates and Predictors of Nutritional Recovery in Malnourished African Children

BACKGROUND

Malnourished children show variable growth responses to nutritional rehabilitation. We aimed to investigate whether these differences could be explained by variations in growth and energy-regulating hormones.

METHODS

Quasi-experimental study: Children aged 6-24 months in rural Gambia were recruited to controls if weight-for-height z-score (WHZ) > -2 (n = 22), moderate acute malnutrition if WHZ < -2 and > -3 (n = 18) or severe acute malnutrition if WHZ < -3 (n = 20). Plasma hormone and salivary CRP levels were determined by ELISA.

RESULTS

In univariable analyses, increases in weight-for-age z-score (WAZ) in malnourished children were positively correlated with insulin (F-ratio 7.8, p = 0.006), C-peptide (F-ratio 12.2, p < 0.001) and cortisol (F-ratio 5.0, p = 0.03). In multivariable analysis, only baseline C-peptide (F-ratio 7.6, p = 0.009) predicted the changes in WAZ over 28 days of interventions.

CONCLUSION

In rural Gambian, malnourished children, although it cannot be used in isolation, baseline C-peptide was a predictor of future response to rehabilitation.

An Adjuvanted A(H5N1) Subvirion Vaccine Elicits Virus-Specific Antibody Response and Improves Protection Against Lethal Influenza Viral Challenge in Mouse Model of Protein Energy Malnutrition

Background

Protein energy malnutrition (PEM) increases susceptibility to infectious diseases, including influenza infection, but no studies have addressed the potential influences of PEM on the immunogenicity and protective efficacy of avian influenza A(H5N1) vaccine.

Methods

We investigated the role of PEM on vaccine-mediated protection after a lethal challenge with recombinant A(H5N1) virus using isocaloric diets providing either adequate protein (AP; 18% protein) or very low protein (VLP; 2% protein) in an established murine model of influenza vaccination.

Results

We demonstrated that mice maintained on a VLP diet succumb to lethal challenge at greater rates than mice maintained on an AP diet, despite comparable immunization regimens. Importantly, there was no virus-induced mortality in both VLP and AP groups of mice when either group was immunized with adjuvanted low-dose A(H5N1) subvirion vaccine.

Conclusions

Our results suggest that adjuvanted vaccination in populations where PEM is endemic may be one strategy to boost vaccination-promoted immunity and improve outcomes associated with highly pathogenic A(H5N1).

A genome-wide association study of anorexia nervosa suggests a risk locus implicated in dysregulated leptin signaling

We conducted a genome-wide association study (GWAS) of anorexia nervosa (AN) using a stringently defined phenotype. Analysis of phenotypic variability led to the identification of a specific genetic risk factor that approached genome-wide significance (rs929626 in EBF1 (Early B-Cell Factor 1); P = 2.04 × 10^-7; OR = 0.7; 95% confidence interval (CI) = 0.61-0.8) with independent replication (P = 0.04), suggesting a variant-mediated dysregulation of leptin signaling may play a role in AN. Multiple SNPs in LD with the variant support the nominal association. This demonstrates that although the clinical and etiologic heterogeneity of AN is universally recognized, further careful sub-typing of cases may provide more precise genomic signals. In this study, through a refinement of the phenotype spectrum of AN, we present a replicable GWAS signal that is nominally associated with AN, highlighting a potentially important candidate locus for further investigation.

Quantitative proteomics of rat livers shows that unrestricted feeding is stressful for proteostasis with implications on life span

Studies in young mammals on the molecular effects of food restriction leading to prolong adult life are scares. Here, we used high-throughput quantitative proteomic analysis of whole rat livers to address the molecular basis for growth arrest and the apparent life-prolonging phenotype of the food restriction regimen. Over 1800 common proteins were significantly quantified in livers of ad libitum, restriction- and re-fed rats, which summed up into 92% of the total protein mass of the cells. Compared to restriction, ad libitum cells contained significantly less mitochondrial catabolic enzymes and more cytosolic and ER HSP90 and HSP70 chaperones, which are hallmarks of heat- and chemically-stressed tissues. Following re-feeding, levels of HSPs nearly reached ad libitum levels. The quantitative and qualitative protein values indicated that the restriction regimen was a least stressful condition that used minimal amounts of HSP-chaperones to maintain optimal protein homeostasis and sustain optimal life span. In contrast, the elevated levels of HSP-chaperones in ad libitum tissues were characteristic of a chronic stress, which in the long term could lead to early aging and shorter life span.

Late-Pregnancy Salivary Cortisol Concentrations of Ghanaian Women Participating in a Randomized Controlled Trial of Prenatal Lipid-Based Nutrient Supplements

BACKGROUND

High circulating cortisol is associated with miscarriage, preterm birth, and low birth weight. Research in nonpregnant individuals suggests that improved nutrition may lower cortisol concentrations. It is unknown whether nutritional supplementation during pregnancy lowers cortisol.

OBJECTIVE

Our objective was to determine whether women receiving a lipid-based nutrient supplement (LNS) throughout pregnancy would have lower salivary cortisol at 36 wk gestation compared with women receiving other nutrient supplements.

METHODS

We conducted a randomized controlled trial in 1320 pregnant Ghanaian women at ≤20 wk gestation who were assigned to receive daily throughout pregnancy: 1) 60 mg iron + 400 μg folic acid (IFA), 2) multiple micronutrients (MMNs), or 3) 20 g LNS (containing 118 kcal, 22 micronutrients, and protein). Morning salivary cortisol was collected from a subsample at baseline and at 28 and 36 wk gestation.

RESULTS

A total of 758 women had cortisol measurements at 28 or 36 wk gestation. Salivary cortisol at 36 wk gestation did not differ between groups and was (mean ± SE) 7.97 ± 0.199 in the IFA group, 7.84 ± 0.191 in the MMN group, and 7.77 ± 0.199 nmol/L in the LNS group, when adjusted for baseline cortisol, time of waking, and time between waking and saliva collection (P = 0.67). There was an interaction between supplementation group and women's age (continuous variable, P-interaction = 0.03); and when age was dichotomized by the median, significant differences in salivary cortisol concentrations between groups were seen in women ≤26 y of age (IFA = 8.23 ± 0.284 nmol/L, MMN = 8.20 ± 0.274 nmol/L, and LNS = 7.44 ± 0.284 nmol/L; P = 0.03) but not in women >26 y old (IFA = 7.71 ± 0.281 nmol/L, MMN = 7.50 ± 0.274 nmol/L, and LNS = 8.08 ± 0.281 nmol/L; P = 0.13).

CONCLUSIONS

We conclude that supplementation with LNSs or MMNs during pregnancy did not affect the cortisol concentration in the study population as a whole, in comparison with IFA, but that LNS consumption among younger women may lead to lower cortisol at 36 wk gestation. This trial was registered at clinicaltrials.gov as NCT00970866.

Neonatal low-protein diet reduces the masticatory efficiency in rats

Little is known about the effects of undernutrition on the specific muscles and neuronal circuits involved in mastication. The aim of this study was to document the effects of neonatal low-protein diet on masticatory efficiency. Newborn rats whose mothers were fed 17% (nourished (N), n 60) or 8% (undernourished (U), n 56) protein were compared. Their weight was monitored and their masticatory jaw movements were video-recorded. Whole-cell patch-clamp recordings were performed in brainstem slice preparations to investigate the intrinsic membrane properties and N-methyl-d-aspartate-induced bursting characteristics of the rhythmogenic neurons (N, n 43; U, n 39) within the trigeminal main sensory nucleus (NVsnpr). Morphometric analysis (N, n 4; U, n 5) were conducted on masseteric muscles serial cross-sections. Our results showed that undernourished animals had lower numbers of masticatory sequences (P=0·049) and cycles (P=0·045) and slower chewing frequencies (P=0·004) (N, n 32; U, n 28). Undernutrition reduced body weight but had little effect on many basic NVsnpr neuronal electrophysiological parameters. It did, however, affect sag potentials (P<0·001) and rebound firing (P=0·005) that influence firing pattern. Undernutrition delayed the appearance of bursting and reduced the propensity to burst (P=0·002), as well as the bursting frequency (P=0·032). Undernourished animals showed increased and reduced proportions of fibre type IIA (P<0·0001) and IIB (P<0·0001), respectively. In addition, their fibre areas (IIA, P<0·001; IIB, P<0·001) and perimeters (IIA, P<0·001; IIB, P<0·001) were smaller. The changes observed at the behavioural, neuronal and muscular levels suggest that undernutrition reduces chewing efficiency by slowing, weakening and delaying maturation of the masticatory muscles and the associated neuronal circuitry.

Nutritionally-induced catch-up growth

Malnutrition is considered a leading cause of growth attenuation in children. When food is replenished, spontaneous catch-up (CU) growth usually occurs, bringing the child back to its original growth trajectory. However, in some cases, the CU growth is not complete, leading to a permanent growth deficit. This review summarizes our current knowledge regarding the mechanism regulating nutrition and growth, including systemic factors, such as insulin, growth hormone, insulin- like growth factor-1, vitamin D, fibroblast growth factor-21, etc., and local mechanisms, including autophagy, as well as regulators of transcription, protein synthesis, miRNAs and epigenetics. Studying the molecular mechanisms regulating CU growth may lead to the establishment of better nutritional and therapeutic regimens for more effective CU growth in children with malnutrition and growth abnormalities. It will be fascinating to follow this research in the coming years and to translate the knowledge gained to clinical benefit.

Determinants of GH resistance in malnutrition

States of undernutrition are characterized by GH resistance. Decreased total energy intake, as well as isolated protein-calorie malnutrition and isolated nutrient deficiencies, result in elevated GH levels and low levels of IGF1. We review various states of malnutrition and a disease state characterized by chronic undernutrition - anorexia nervosa - and discuss possible mechanisms contributing to the state of GH resistance, including fibroblast growth factor 21 and Sirtuin 1. We conclude by examining the hypothesis that GH resistance is an adaptive response to states of undernutrition, in order to maintain euglycemia and preserve energy.

Effects of glutamine alone or in combination with zinc and vitamin A on growth, intestinal barrier function, stress and satiety-related hormones in Brazilian shantytown children

OBJECTIVE

To determine the impact of supplemental zinc, vitamin A, and glutamine alone or in combination on growth, intestinal barrier function, stress and satiety-related hormones among Brazilian shantytown children with low median height-for-age z-scores.

METHODS

A randomized, double-blind, placebo-controlled trial was conducted in children aged two months to nine years from the urban shanty compound community of Fortaleza, Brazil. Demographic and anthropometric information was assessed. The random treatment groups available for testing (a total of 120 children) were as follows: (1) glutamine alone, n = 38; (2) glutamine plus vitamin A plus zinc, n = 37; and a placebo (zinc plus vitamin A vehicle) plus glycine (isonitrogenous to glutamine) control treatment, n = 38. Leptin, adiponectin, insulin-like growth factor (IGF-1), and plasma levels of cortisol were measured with immune-enzymatic assays; urinary lactulose/mannitol and serum amino acids were measured with high-performance liquid chromatography. ClinicalTrials.gov: NCT00133406.

RESULTS

Glutamine treatment significantly improved weight-for-height z-scores compared to the placebo-glycine control treatment. Either glutamine alone or all nutrients combined prevented disruption of the intestinal barrier function, as measured by the percentage of lactulose urinary excretion and the lactulose:mannitol absorption ratio. Plasma leptin was negatively correlated with plasma glutamine (p = 0.002) and arginine (p = 0.001) levels at baseline. After glutamine treatment, leptin was correlated with weight-for-age (WAZ) and weight-for-height z-scores (WHZ) (p≤0.002) at a 4-month follow-up. In addition, glutamine and all combined nutrients (glutamine, vitamin A, and zinc) improved the intestinal barrier function in these children.

CONCLUSION

Taken together, these findings reveal the benefits of glutamine alone or in combination with other gut-trophic nutrients in growing children via interactions with leptin.

Protein energy malnutrition decreases immunity and increases susceptibility to influenza infection in mice

BACKGROUND

Protein energy malnutrition (PEM), a common cause of secondary immune deficiency in children, is associated with an increased risk of infections. Very few studies have addressed the relevance of PEM as a risk factor for influenza.

METHODS

We investigated the influence of PEM on susceptibility to, and immune responses following, influenza virus infection using isocaloric diets providing either adequate protein (AP; 18%) or very low protein (VLP; 2%) in a mouse model.

RESULTS

We found that mice maintained on the VLP diet, when compared to mice fed with the AP diet, exhibited more severe disease following influenza infection based on virus persistence, trafficking of inflammatory cell types to the lung tissue, and virus-induced mortality. Furthermore, groups of mice maintained on the VLP diet showed significantly lower virus-specific antibody response and a reduction in influenza nuclear protein-specific CD8(+) T cells compared with mice fed on the AP diet. Importantly, switching diets for the group maintained on the VLP diet to the AP diet improved virus clearance, as well as protective immunity to viral challenge.

CONCLUSIONS

Our results highlight the impact of protein energy on immunity to influenza infection and suggest that balanced protein energy replenishment may be one strategy to boost immunity against influenza viral infections.

Obesity and its diagnostic methods in Turkish children

OBJECTIVE

The application of body mass index (BMI) for obesity classification in all population studies has been questioned by the scientific community. It has been found that the bioelectrical impedance analysis (BIA) is an accurate method for screening obesity. This study was conducted to evaluate the accuracies of BMI, skinfold thickness (SFT), leptin and BIA measurements in obesity classification and to find correlations between BIA and the other indicators for obesity.

MATERIALS AND METHODS

This case-control study included 178 children of whom 90 were in the obese group and 88 in the control group. The study measured BMI, SFT, leptin level and BIA-mediated body fat percentage (BIA BFP) in each child.

RESULTS

The BMIs, leptin levels, SFTs and BIA BFPs of children in the obese group were found to be higher than those in the control group (p<0.001). The measurement of BIA BFP strongly correlated with BMI, SFT and waist circumference, whereas BIA BFP measurement showed weak-moderate correlation with leptin level.

CONCLUSION

Bioelectrical impedance analysis was found to be an accurate measure of BFP in obesity. In addition, BIA may prevent the incorrect diagnosis of obesity as determined by BMI alone, especially in boys during the pubertal period.

Language skills and intelligence quotient of protein energy malnutrition survivors

The study was conducted on 33 children aged 3-6 years who suffered from protein energy malnutrition (PEM) during infancy in comparison to 30 matching children to assess the long-term deficits in cognition and language skills. The patients' files were revised to record their admission and follow-up data and history, clinical examination, intelligence quotient and language assessment were done. The study revealed that 2-5 years from the acute attack the PEM patients were still shorter than the controls and their cognitive abilities were poorer. Their mental ages and language skills were mostly determined by their height and the duration of follow-up during their acute illness. Additionally their diet after the 3-5 years is still defective and does not meet their recommended daily allowance. These observations urge us to continue following these patients for longer durations to make sure no permanent damage occurs due to the PEM insult to the growing brain.

Profound hypoglycemia in starved, ghrelin-deficient mice is caused by decreased gluconeogenesis and reversed by lactate or fatty acids

When mice are subjected to 7-day calorie restriction (40% of normal food intake), body fat disappears, but blood glucose is maintained as long as the animals produce ghrelin, an octanoylated peptide that stimulates growth hormone secretion. Mice can be rendered ghrelin-deficient by knock-out of the gene encoding either ghrelin O-acyltransferase, which attaches the required octanoate, or ghrelin itself. Calorie-restricted, fat-depleted ghrelin O-acyltransferase or ghrelin knock-out mice fail to show the normal increase in growth hormone and become profoundly hypoglycemic when fasted for 18-23 h. Glucose production in Goat(-/-) mice was reduced by 60% when compared with similarly treated WT mice. Plasma lactate and pyruvate were also low. Injection of lactate, pyruvate, alanine, or a fatty acid restored blood glucose in Goat(-/-) mice. Thus, when body fat is reduced by calorie restriction, ghrelin stimulates growth hormone secretion, which allows maintenance of glucose production, even when food intake is eliminated. In humans with anorexia nervosa or kwashiorkor, ghrelin and growth hormone are known to be elevated, just as they are in fat-depleted mice. We suggest that these two hormones prolong survival in starved humans as they do in mice.

Nutrition and bone growth in pediatrics

Children's growth is a hallmark of their normal development and the association between nutrition and linear growth in children is well accepted. Growth requires an adequate supply of many different nutritional factors, some form the "building materials," whereas others play regulatory roles. In this article we describe the growth of the growth plate and discuss the role of nutritional affected hormones on this process. In addition we describe the effect of local regulators and nutritional factors on the growth process and suggest the involvement of new regulatory factors in the translation of nutrition to growth.

The effect of Helicobacter pylori and economic status on growth parameters and leptin, ghrelin, and insulin-like growth factor (IGF)-I concentrations in children

BACKGROUND

It was suggested that gastric colonization with Helicobacter pylori (H. pylori) was associated with suboptimal nutrition and growth in childhood. Furthermore, several studies indicated a relationship between H. pylori colonization and alterations in the circulating levels of growth-related molecules (GRM). Accordingly, in this study, we investigate the effect of H. pylori infection on GRMs and on the growth of healthy school children, taking into consideration the effect of their economic status (ES) and anthropometric indices of their parents.

METHODS

To acquire sociodemographic and anthropometric nutritional parameters and to detect H. pylori-specific serum IgG antibodies and growth-related molecules, we evaluated a total of 473 children attending four different primary and secondary schools in Istanbul. Subsequently, we assessed the effect of H. pylori on growth-related parameters (weight for age SDS, height for age SDS, BMI SDS, TSF, and waist-to-hip ratio) and on GRMs (leptin, ghrelin, and insulin-like growth factor-1 (IGF-1)), controlling for age, gender, family income, household crowding (HC), breastfeeding, maternal and paternal BMI SDS, and midparental height SDS with complex statistical models.

RESULTS

Of the 473 children (275 F/198 M, age 6-15 years; mean: 10.3 ± 0.1 years), 161 (34%) were H. pylori-positive. The prevalence of H. pylori was significantly higher in lower economic status (ES) groups, in children living in crowded houses, and in older age groups. Using simple statistical models, we did not find any significant associations between H. pylori infection and the growth parameters. However, in complex models for height for age SDS and for weight for age SDS, there was a significant interaction between H. pylori infection status and ES. Whereas in H. pylori-positive subjects, mid-income family children were both taller and heavier than the low-income group, there was no such an association in H. pylori-negative subjects. Among biochemical parameters, only ghrelin levels were associated with H. pylori infection in all models. Leptin levels were associated with HC in girls, whereas none of the parameters was significantly associated with leptin levels in boys. For IGF-1 levels, for boys, age and maternal BMI, and for girls, age and HC were significantly associated with IGF-1 levels.

CONCLUSION

We suggest that H. pylori may impair growth significantly only in susceptible children where unfavorable socioeconomic conditions facilitate its action, probably through mechanisms, at least in part, involving growth-related molecules.

Effect of honey on 50% complement hemolytic activity in infants with protein energy malnutrition: a randomized controlled pilot study

Protein energy malnutrition (PEM) is associated with a significant impairment of cell-mediated immunity and complement system, which may be responsible for the high incidence of infections among these patients. This study was designed to examine the effect of honey, as a natural substance, on the 50% complement hemolytic activity (CH50) in patients with PEM. Thirty patients with PEM and 20 healthy infants serving as controls participated in this study. The patients were randomized to receive either honey (group 1) or placebo (group 2), in addition to conventional nutritional rehabilitation therapy. Measurements of weight, midarm circumference, skin fold thickness, serum albumin, and CH50 were done for all patients before and after 2 weeks of rehabilitation. Before nutritional rehabilitation, the CH50 was significantly lower in the PEM groups compared with the control. However, after rehabilitation, the CH50 increased significantly in both PEM groups, compared with the pre-interventional state and with the controls. Moreover, the rise of CH50 was significantly more in the honey group compared with the placebo. On the other hand, the improvement in the anthropometric measures and serum albumin did not differ significantly between the honey and placebo groups after rehabilitation. Thus honey supplementation in patients with PEM increased the level of CH50. Whether this would have an effect on the frequency and severity of infections in patients with PEM needs further studies.

Altered metabolism and lipodystrophy in the early B-cell factor 1-deficient mouse

We previously reported that mice deficient for the transcription factor early B-cell factor (Ebf1) exhibit markedly increased numbers of osteoblasts, bone formation rate, and serum osteocalcin, but the bone marrow of Ebf1(-/-) mice is also striking in its increased marrow adiposity. The purpose of this work was to analyze the metabolic phenotype that accompanies the altered bone morphology of Ebf1(-/-) mice. Whereas marrow adiposity was increased, deposition of white adipose tissue in other regions of the body was severely reduced (sc 40-50%, abdominally 80-85%). Brown adipose exhibited decreased lipid deposition. Subcutaneous and perigonadal white adipose tissue showed a decrease in mRNA transcripts for peroxisomal proliferator-activated receptor-gamma2 and CCAAT/enhancer-binding protein-beta in Ebf1(-/-) tissue compared with wild type. Circulating levels of leptin were decreased in Ebf1(-/-) animals compared with their littermate controls (down 65-95%), whereas adiponectin remained comparable after 2 wk of age. Serum analysis also found the Ebf1(-/-) animals were hypoglycemic and hypotriglyceridemic. After ip injection of insulin, the serum glucose levels in Ebf1(-/-) mice took longer to recover, and after a glucose challenge the Ebf1(-/-) animals reached serum glucose levels almost twice that of their wild-type counterparts. Measurement of circulating pancreatic hormones revealed normal or reduced insulin levels in the Ebf1(-/-) mice, whereas glucagon was significantly increased (up 1.7- to 8.5-fold). Metabolically the Ebf1(-/-) mice had increased O(2) consumption, CO(2) production, food and water intake, and activity. Markers for gluconeogenesis, however, were decreased in the Ebf1(-/-) mice compared with controls. In conclusion, the Ebf1-deficient animals exhibit defects in adipose tissue deposition with increased marrow adiposity and impaired glucose mobilization.

Nutrition and bone growth in pediatrics

Children's growth is a hallmark of their normal development and the association between nutrition and linear growth in children is well accepted. Growth requires an adequate supply of many different nutritional factors, some form the "building materials," whereas others play regulatory roles. In this article we describe the growth of the growth plate and discuss the role of nutritional affected hormones on this process. In addition we describe the effect of local regulators and nutritional factors on the growth process and suggest the involvement of new regulatory factors in the translation of nutrition to growth.

Serum ghrelin in infants with protein-energy malnutrition

BACKGROUND

Ghrelin is an appetite and weight physiologic controller. The question is whether there is a relation between ghrelin and protein-energy malnutrition (PEM). Our aim was to assess serum ghrelin in these patients and its relation to different patient variables.

METHODS

A cross-sectional study was conducted on 30 PEM infants (12 marasmic=Ia, 10 kwashiorkor=Ib and 8 marasmic kwashiorkor=Ic) and 15 age and sex matched controls (II). Plasma ghrelin was measured in all subjects using radioimmunoassay with thorough medical history and clinical assessment.

RESULTS

The mean serum ghrelin levels were significantly higher among the 3 patient subgroups than controls with no significant inter-subgroup differences. The presence of intestinal parasitic infestations or edema, type of milk feeding and gender had no significant effects on serum ghrelin levels.

CONCLUSION

Serum ghrelin is elevated in PEM as an adapting consequence of the malnutrition rather than a primary event. Although this elevation may not be helpful to correct the growth failure because of deficient nutrients, it may prove to have a role in the catch up phenomenon after the recovery. Further research should be directed toward therapeutic trials of ghrelin in the recovery phase.

Low-dose hydrocortisone in pediatric septic shock: an exploratory study in a third world setting

OBJECTIVE

To study the efficacy of low-dose intravenous hydrocortisone therapy in the management of pediatric septic shock with respect to the time taken for shock reversal and requirement of inotropes.

DESIGN

Open label randomized pilot study.

SETTING

Pediatric intensive care unit of a tertiary care pediatric center in a third world country.

PATIENTS

Thirty-eight children, 2 months-12 yrs of age, with septic shock unresponsive to fluid therapy alone.

INTERVENTION

Intravenous hydrocortisone 5 mg/kg/day in four divided doses followed by half the dose for a total duration of 7 days or normal saline (similar amount in a similar manner) for the same duration.

RESULTS

There was a trend toward earlier reversal of shock (median 49.5 vs. 70 hrs, p = 0.65, Mann-Whitney U test) and lower inotropes requirement (median {lsqb;10th-90th centile{rsqb; inotropes score: 20 {lsqb;15-60{rsqb; vs. 50 {lsqb;20-80{rsqb;, p = 0.15) in the hydrocortisone-treated patients as compared with controls, although the difference was not statistically significant. Mortality rate was similar in both groups.

CONCLUSIONS

Our data, although, inconclusive favor the need for a study with a larger sample size to clearly define role of low-dose hydrocortisone in pediatric septic shock in developing countries, while taking in consideration effect of malnutrition, delayed presentations, and their interactions with the hypothalamic-pituitary-adrenocortical axis.

Effects of short-term mild calorie restriction diet and renutrition with ruminant milks on leptin levels and other metabolic parameters in mice

OBJECTIVE

The adaptation of an organism to a calorie-restricted diet is characterized by metabolic, endocrine, and immunologic changes. The objective of this study was to determine, in a mouse model, the changes in serum leptin levels in response to short-term mild calorie-restricted and renutrition diets using different ruminant milks.

METHODS

Weaned Swiss albino mice were fed with a mild calorie-restricted diet for 12 d, after which they were renourished with cow, goat, sheep, or buffalo milk for 7 d. Body, thymus, and spleen weights and biochemical, hematologic, and endocrine parameters were evaluated.

RESULTS

The mild calorie restriction did not significantly modify insulin and leptin levels. The renutrition diets increased insulin levels, being significant (P < 0.05) only when buffalo and sheep milks were used. Leptin concentrations increased in the control ad libitum (AD) group during the assayed period. After the administration of cow and goat milks, lower leptin levels were observed compared with the control AD group. All repletion diets significantly increased body, thymus, and spleen weights; however, spleen weight did not reach the values observed in the control AD group. Serum glucose and triacylglycerol levels increased after feeding with the renutrition diets. However, serum cholesterol did not increase after the renutrition period. We observed a significant decrease (P < 0.05) in the leukocyte counts in calorie-restricted mice in comparison with AD mice; after the renutrition period, the leukocyte count did not reach the values for the AD mice.

CONCLUSION

This study suggests that a short-term change in diet with a relatively low body weight loss does not significantly affect leptin concentrations in our mouse model. However, the assayed milks could be effectively used as alternative milk sources for weight gain and for the improvement of other metabolic parameters.

Serum levels of ghrelin, leptin, IGF-I, IGFBP-3, insulin, thyroid hormones and cortisol in prepubertal children with iron deficiency

The aim of the present study is to investigate possible alterations in ghrelin and other hormone levels related to appetite and somatic growth in children with iron deficiency anemia. Twenty-five patients and 25 healthy controls that were prepubertal and within normal limits regarding height and BMI standard deviation scores were recruited. Ghrelin, leptin, IGF-I, IGFBP-3, insulin, thyroid hormones and cortisol levels were studied. Ghrelin, insulin and IGF-I levels were significantly low in the study group (ghrelin 13.58 +/- 16.32 vs. 35.39 +/- 23.69 ng/ml, p<.001; insulin 3.41 +/- 2.42 vs. 5.67 +/- 1.09 mU/ml, p = .008 and IGF-I 126.94 +/- 92.82 vs. 203 +/- 105.1 ng/ml, p = .015). We concluded that low ghrelin and insulin levels might be causes of the appetite loss in iron deficiency and as a result of appetite loss and undernutrition as well as by direct effects they might be related with growth retardation, which could be also influenced by low IGF-I levels.

Dietary glycemic index and glucose, insulin, insulin-like growth factor-I, insulin-like growth factor binding protein 3, and leptin levels in patients with acne

BACKGROUND

Several isolated observations have suggested that acne can develop in groups when a high glycemic index diet is adopted.

OBJECTIVE

This study was designed to examine associations among daily diet glycemic index, glycemic loads, serum insulin levels, and acne.

METHODS

A total of 49 patients with acne and 42 healthy control subjects were included in the study. At the initial visit, fasting glucose, insulin, insulin-like growth factor-I, insulin-like growth factor binding protein 3, and leptin levels were measured. A voluntary self-completed questionnaire was administered and participants were asked how frequently they consumed the specified amount of food. Overall glycemic index and dietary glycemic load were calculated.

RESULTS

No significant differences were observed between patients with acne and control subjects in serum glucose, insulin, leptin levels, overall glycemic index, or dietary glycemic load.

LIMITATIONS

The information and data obtained from this questionnaire were limited to patients' own recollections.

CONCLUSION

Results of this study indicate that dietary glycemic index, glycemic load, and insulin levels do not have a role in pathogenesis of acne in younger patients.

Nutrition in children with CRF and on dialysis

The objectives of this study are: (1) to understand the importance of nutrition in normal growth; (2) to review the methods of assessing nutritional status; (3) to review the dietary requirements of normal children throughout childhood, including protein, energy, vitamins and minerals; (4) to review recommendations for the nutritional requirements of children with chronic renal failure (CRF) and on dialysis; (5) to review reports of spontaneous nutritional intake in children with CRF and on dialysis; (6) to review the epidemiology of nutritional disturbances in renal disease, including height, weight and body composition; (7) to review the pathological mechanisms underlying poor appetite, abnormal metabolic rate and endocrine disturbances in renal disease; (8) to review the evidence for the benefit of dietetic input, dietary supplementation, nasogastric and gastrostomy feeds and intradialytic nutrition; (9) to review the effect of dialysis adequacy on nutrition; (10) to review the effect of nutrition on outcome.

Association between insulin-like growth factor-1, insulin-like growth factor-binding protein-1 and leptin levels with nutritional status in 1–3-year-old children, residing in the central region of Limpopo Province, South Africa

The present study evaluated levels of growth factors and their associations with nutritional status with emphasis on stunting in children at 1 and 3 years of age. A follow-up study on a birth cohort (n 219) of children from villages in the central region of the Limpopo Province was undertaken. Of the original cohort, 156 and 162 could be traced and assessed at ages 1 and 3 years, respectively. Data collected included socio-demographic characteristics, anthropometric measurements, dietary intake and fasting blood (collected from 116 and 145 children at 1 and 3 years, respectively) for growth factor analysis (insulin-like growth factor (IGF)-1, IGF binding protein (BP)-1, IGFBP-3, leptin, glucose and insulin). At 1 year it was found that stunted children had lower leptin levels while their IGFBP-1 levels were higher than that in normal children. These differences were, however, not observed at 3 years. Furthermore at 1 year the biochemical parameters were more related to length measures whereas at 3 years the parameters were more associated with weight measures. The observed stunting in this group of children may be a result of chronic undernutrition resulting in long-term growth faltering which is already evident at 1 year. Thus the observed phenomenon might be an adaptive mechanism adopted by children's metabolic processes as they grow up in an environment with inadequate essential nutrients due to poor weaning practices and consumption of a diet of poor quality, resulting in them gaining more weight at the expense of linear growth.

Paraoxonase, total antioxidant activity and peroxide levels in marasmic children: Relationships with leptin

OBJECTIVES

The aim of this study was to investigate the oxidant/antioxidant status, paraoxonase (PON) activity and leptin levels in children with marasmic malnutrition.

DESIGN AND METHODS

Thirty marasmic children (age 14.4+/-10.3 months) and 28 control subjects were included. Plasma PON activity, total antioxidant activity (TAO), total peroxide (TPX) and leptin levels were measured.

RESULTS

Malnourished children had significantly lower leptin (3.6+/-1.1 vs. 11.8+/-4.5 ng/mL, P<0.001), PON activity (66.4+/-28.6 vs. 221.3+/-31.6 IU/L, P<0.001) and TAO (1.44+/-0.12 vs. 2.45+/-0.61 mmol Trolox equiv/L, P<0.001); and higher TPX (15.6+/-6.4 vs. 5.9+/-1.9 micromol/L, P<0.001) values than in controls. Significant negative correlation was found between PON and TPX (P=0.040) and positive correlation between TAO and BMI (P=0.034) in patients. No significant correlation was found between leptin and oxidant/antioxidant parameters (P>0.05).

CONCLUSIONS

Children with marasmic malnutrition had increased pro-oxidant and decreased antioxidant status. Extent of oxidative stress increases with malnutrition severity. Antioxidants could be given during nutritional rehabilitation.

Relationships between leptin, insulin, IGF-1 and IGFBP-3 in children with energy malnutrition

OBJECTIVES

Leptin has a key role in energy homeostasis and there may be a link between leptin and insulin-like growth factor-1 (IGF-1) system. The aim of this study was to analyze the relationships between long-lasting insufficient caloric intake (marasmus), leptin and IGF-1 system.

DESIGN AND METHODS

The study group consisted of 30 marasmic children and control group included 28 healthy children. After an overnight fasting; leptin, insulin, IGF-1 and IGFBP-3 levels were measured.

RESULTS

Marasmic children had significantly lower body weight, height, mid-arm circumference (MAC), skinfold thickness, mean serum leptin, insulin, IGF-1 and IGFBP-3 levels compared with healthy subjects (P<0.05). Serum IGF-1 and IGFBP-3 levels were significantly correlated with insulin, MAC and height Z score in patients (P<0.05). In controls, significant positive correlations were found between BMI, IGF-1 and leptin (P<0.05).

CONCLUSIONS

Energy malnutrition is characterized by the important decreases in the leptin, insulin, IGF-1 and IGFBP-3 levels. Understanding details of these changes may lead to new therapeutic approaches in disease states associated with malnutrition.

Serum leptin levels in childhood celiac disease

OBJECTIVE

Leptin has effects on growth and is also involved in immune regulation. We thought that with its intestinal histopathologic alterations due to immune mechanisms, and subsequent malnutrition and/or growth failure, celiac disease (CD) deserves interest regarding leptin status.

METHOD

Serum leptin levels of 19 children with CD on admission and 1 year after gluten-free diet (GFD) and of 16 healthy children were determined.

RESULTS

Mean age was 9.7+/-3.3 years. Mean serum leptin level of children with CD on admission and of healthy children were 1.60+/-0.63 ng/mL, and 3.98+/-1.49 ng/mL, respectively (P: 0.0001). Mean serum leptin level under GFD was 4.55+/-1.97 ng/mL. There was a statistical significant difference between serum levels determined before and 1 year after GFD (P: 0.001) and between those of under GFD and healthy children (P: 0.001). Of 19 patients with CD, 10 (52.6%) showed Marsh IIIc, other 9 (47.4%) showed Marsh IIIa histologic lesions. Mean serum leptin level of children with Marsh IIIc and Marsh IIIa were not different (1.70+/-0.73 ng/mL vs. 1.45+/-0.59 ng/mL). Leptin was correlated with body mass index in healthy children, and in CD both before and after GFD (P<0.001). Mean lumbar z score of the patients on admission and after GFD were 2.7+/-1.3 and 1.9+/-0.8, respectively (P: 0.048). Serum leptin level was not correlated with lumbar z score either before or after GFD.

CONCLUSIONS

Serum leptin level is affected in childhood CD, it is not directly related to histopathologic findings, and is responsive to GFD. Further studies investigating its level in different clinical and histopathologic presentations might give clear clues about the role of leptin in CD.

Leptin Receptor Expression and Signaling in Lymphocytes: Kinetics During Lymphocyte Activation, Role in Lymphocyte Survival, and Response to High Fat Diet in Mice

Leptin has direct effects not only on neuroendocrine function and metabolism, but also on T cell-mediated immunity. We report in this study that leptin receptor (ObR) is expressed on resting normal mouse CD4(+), CD8(+), B cells, and monocyte/macrophages. ObR expression is up-regulated following cell activation, but with different kinetics, in different lymphocyte subsets. Leptin binding to ObR results in increased STAT-3 activation in T cells, with a different activation pattern in resting vs anti-CD3 Ab stimulated T cells. Leptin also promotes lymphocyte survival in vitro by suppressing Fas-mediated apoptosis. B lymphocytes appear to be more susceptible to the antiapoptotic effects of leptin, and they show higher surface expression of ObR, compared with T cells. Moreover, CD4(+) T cells isolated from ObR-deficient mice displayed a reduced proliferative response, compared with normal controls. Furthermore, ObR/STAT-3-mediated signaling in T lymphocytes is decreased in the diet-induced obese mouse model of obesity and leptin resistance. In summary, our findings show that the ObR is expressed on normal mouse lymphocyte subsets, that leptin plays a role in lymphocyte survival, and that leptin alters the ObR/STAT-3-mediated signaling in T cells. Taken together, our data further support the notion that nutritional status acting via leptin-dependent mechanisms may alter the nature and vigor of the immune response.

Leptin responses to insulin administration in children with short stature

Abstract The aim of the study was to investigate the effect of standard insulin tolerance test on plasma leptin levels in children with idiopathic short stature (ISS) and in children with growth hormone deficiency (GHD). Furthermore, plasma leptin levels were analyzed with regard to age, body mass index (BMI), and plasma levels of human growth hormone and of insulin-like growth factor-1 (IGF-1). Sixty-three patients with a height below the third percentile, an age of 10.24 +/- 0.40 years and a BMI standard deviation score (SDS) of -0.78 +/- 0.13 (weight SDS -0.07 +/- 0.12; height SDS -2.39 +/- 0.10) were investigated (mean +/- SD). Based on responses to insulin tolerance test, the patients were classified as ISS (n = 49) or GHD (n = 14). Plasma leptin levels were significantly lower in all patients 60 minutes ( P < .001) and 120 minutes ( P < .001) after insulin administration. This effect was independent of GHD, and no difference in leptin decrease was found when comparing patients with ISS to those with GHD. A correlation was found when comparing plasma leptin levels of all patients to BMI SDS (r = 0.43; P < .001) and plasma IGF-1 levels (r = 0.31; P < .01). Furthermore, positive correlation was found when BMI SDS was compared to IGF-1 (r = 0.25; P < .05). In summary, we found that insulin administration in children with short stature decreases plasma leptin levels, equally in those with and without GHD.