Nutrition and bone growth in pediatrics

Tartrate-resistant acid phosphatase (TRAP/ACP5) promotes bone length, regulates cortical and trabecular bone mass, and maintains growth plate architecture and width in a sex- and site-specific manner in mice

Tartrate-resistant acid phosphatase (TRAP) serum levels reflect osteoclast number, bone remodeling activity, and fracture risk. Deletion or loss of function of TRAP results in short stature in mice and man. Yet, the impact and mechanisms of TRAP for the site- and sex-specific development of bone and cartilage is not well understood. Here, we use a global TRAP knockout (TRAPKO) and wildtype littermate control (WT) mice of both sexes to investigate TRAP as a possible sex- and site-specific regulator of bone and growth plate development. TRAPKO mice of both sexes weighed less and had shorter tibial length than their WT, features that were more accentuated in male than female TRAPKO mice. These changes were not associated with a general reduction in growth as not all organs displayed a proportionally lower mass, and serum IGF-1 was unchanged. Using μCT and site-specificity analysis of the cortical bone revealed wider proximal tibia, a higher trabecular thickness, and lower trabecular separation in male TRAPKO compared to WT mice, an effect not seen in female mice. Histomorphometric analysis revealed that the growth plate height as well as height of terminal hypertrophic chondrocytes were markedly increased, and the number of columns was decreased in TRAPKO mice of both sexes. These effects were more accentuated in female mice. Proliferation and differentiation of bone marrow derived macrophages into osteoclasts, as well as C-terminal cross links were normal in TRAPKO mice of both sexes. Collectively, our results show that TRAP regulates bone and cartilage development in a sex-and site-specific manner in mice.

The energetics of childhood: Current knowledge and insights into human variation, evolution, and health

How organisms capture and ultimately use metabolic energy-a limiting resource of life-has profound implications for understanding evolutionary legacies and current patterns of phenotypic variation, adaptation, and health. Energetics research among humans has a rich history in biological anthropology and beyond. The energetics of childhood, however, remains relatively underexplored. This shortcoming is notable given the accepted importance of childhood in the evolution of the unique human life history pattern as well as the known sensitivity of childhood development to local environments and lived experiences. In this review, I have three objectives: (1) To overview current knowledge regarding how children acquire and use energy, highlighting work among diverse human populations and pointing to recent advances and remaining areas of uncertainty; (2) To discuss key applications of this knowledge for understanding human variation, evolution, and health; (3) To recommend future avenues for research. A growing body of evidence supports a model of trade-offs and constraint in childhood energy expenditure. This model, combined with advancements on topics such as the energetics of immune activity, the brain, and the gut, provides insights into the evolution of extended human subadulthood and the nature of variation in childhood development, lifetime phenotype, and health.

Nutritional Approaches as a Treatment for Impaired Bone Growth and Quality Following the Consumption of Ultra-Processed Food

The severe impairment of bone development and quality was recently described as a new target for unbalanced ultra-processed food (UPF). Here, we describe nutritional approaches to repair this skeletal impairment in rats: supplementation with micro-nutrients and a rescue approach and switching the UPF to balanced nutrition during the growth period. The positive effect of supplementation with multi-vitamins and minerals on bone growth and quality was followed by the formation of mineral deposits on the rats' kidneys and modifications in the expression of genes involved in inflammation and vitamin-D metabolism, demonstrating the cost of supplementation. Short and prolonged rescue improved trabecular parameters but incompletely improved the cortical parameters and the mechanical performance of the femur. Cortical porosity and cartilaginous lesions in the growth-plate were still detected one week after rescue and were reduced to normal levels 3 weeks after rescue. These findings highlight bone as a target for the effect of UPF and emphasize the importance of a balanced diet, especially during growth.

Physiological regulation of bone length and skeletal proportion in mammals

NEW FINDINGS

What is the topic of this review? Mechanisms regulating bone length and skeletal proportions What advances does it highlight? The study of differential bone length between leg and finger bones, metatarsals of the Egyptian jerboa and genomic analysis of giraffes.

ABSTRACT

Among mammalian species, skeletal structures vary greatly in size and shape, leading to a dramatic variety of body sizes and proportions. How different bones grow to different lengths, whether among different species, different individuals of the same species, or even in different anatomical parts of our the body, has always been a fascinating subject of research in biology and physiology. In the current review, we focus on some of the recent advances in the field and discuss how these provided important new insights into the mechanisms regulating bone length and skeletal proportions.

Adult characteristics of survivors of early life malnutrition in an impoverished population

BACKGROUND & AIMS

To determine the characteristics of adults who survived early life malnutrition (ELM) and the possible associated factors. The setting is an impoverished community in Kenya. The coastal region of Kenya has a high prevalence of acute protein-energy-malnutrition and stunting.

METHODS

Observational cross-sectional survey where 872 skeletally mature adults of African origin, were surveyed in a period of three months. A discrimination tool to detect ELM survivors was created. Personal, historical and family data were collected in a semi-structured questionnaire. Various observations and body measurements were done. The subjects were grouped into two, those with ELM (Group1), and those without (Group2).

RESULTS

Group1 had 242 participants, 49.8% males, mean age of 49.1 ± 8.7 years. Group2 had 630 participants, 48.3% males, mean age 41.0 ± 9.7 years. The phenotypic characteristics included height, BMI, and head circumference (P < 0.05). Developmental characteristics were duration of schooling, occupation and income (P < 0.001). Factors associated with malnutrition were County of origin, parental education, parental occupation, and family size (P < 0.001).

CONCLUSIONS

There are discernible phenotypic and developmental characteristics associated with adult survivors of ELM. The predisposing factors for ELM are location of birth, parental education and occupation, and family size.

Reduced Final Height and Inadequate Nutritional Intake in Cow's Milk-Allergic Young Adults

BACKGROUND

Growth impairment was previously described in milk-allergic children but was not examined in adults on reaching final height.

OBJECTIVES

To investigate the dietary intake and final stature of young adults with IgE-mediated cow's milk allergy (IgE-CMA) as compared with nonallergic controls.

METHODS

Eighty-seven patients with IgE-CMA, median age 19.5 years (interquartile range [IQR], 17.3-22.7), and 36 control participants without food allergies, median age 22.7 years (IQR, 18.9-26.1), were studied. Anthropometric and nutritional data were collected. Age and gender z-scores were determined according to the Centers for Disease Control and Prevention growth charts. Nutrient intake assessment was based on dietary records. Individuals with conditions or treatments affecting bone metabolism or growth, other than asthma, were excluded.

RESULTS

Mean values of height z-scores were significantly reduced in CMA subjects compared with controls (-0.64 ± 0.9 vs -0.04 ± 0.7, P = .001). In contrast, no differences were found between the 2 groups in weight and body mass index z-scores. Patients with CMA had significantly lower intake of protein, and several essential vitamins (A, B12, and riboflavin) and minerals (calcium, potassium, phosphorus, magnesium, and zinc) compared with controls (P < .05), but the intakes of calories, carbohydrate, and fat were not significantly different between the 2 groups. Differences between actual and expected (based on midparental height) height z-scores were comparable in CMA subjects with or without asthma and between those with and without additional food allergies.

CONCLUSIONS

Young adults who have CMA from infancy are at risk of not reaching their growth potential. Growth and nutritional monitoring and appropriate dietary intervention are of particular importance in these at-risk individuals.

Genetically engineered flavonol enriched tomato fruit modulates chondrogenesis to increase bone length in growing animals

Externally visible body and longitudinal bone growth is a result of proliferation of chondrocytes. In growth disorder, there is delay in the age associated increase in height. The present study evaluates the effect of extract from transgenic tomato fruit expressing AtMYB12 transcription factor on bone health including longitudinal growth. Constitutive expression of AtMYB12 in tomato led to a significantly enhanced biosynthesis of flavonoids in general and the flavonol biosynthesis in particular. Pre-pubertal ovary intact BALB/c mice received daily oral administration of vehicle and ethanolic extract of wild type (WT-TOM) and transgenic AtMYB12-tomato (MYB12-TOM) fruits for six weeks. Animal fed with MYB12-TOM showed no inflammation in hepatic tissues and normal sinusoidal Kupffer cell morphology. MYB12-TOM extract significantly increased tibial and femoral growth and subsequently improved the bone length as compared to vehicle and WT-TOM. Histomorphometry exhibited significantly wider distal femoral and proximal tibial growth plate, increased number and size of hypertrophic chondrocytes in MYB12-TOM which corroborated with micro-CT and expression of BMP-2 and COL-10, marker genes for hypertrophic cells. We conclude that metabolic reprogramming of tomato by AtMYB12 has the potential to improve longitudinal bone growth thus helping in achievement of greater peak bone mass during adolescence.

Effect of a nutritional supplement on growth in short and lean prepubertal children: a prospective, randomized, double-blind, placebo-controlled study

OBJECTIVE

To determine the effect of nutritional supplementation on height, weight, and body mass index (BMI) in short and lean prepubertal children.

STUDY DESIGN

A prospective, randomized, double-blinded, placebo-controlled trial of nutritional supplementation at the endocrinology department of a tertiary pediatric medical center of healthy, lean, short, prepubertal children 3-9-years-old. Anthropometry measurements were measured at 6 months.

RESULTS

Two hundred participants (149 boys) entered the study and 171 (85.5%) completed the intervention period. Baseline characteristics including age, sex, height-SDS, weight-SDS, BMI-SDS, and dietary caloric and protein intakes were similar in the formula and placebo groups. 'Good' consumers (intake of ≥50% of the recommended dose) in the formula group significantly improved height-SDS (P < .001) and weight-SDS (P = .005) with no change in BMI-SDS compared with 'poor' consumers and the placebo group. In the formula-treated group a positive correlation was found between the amount of formula consumed per body weight and the gain in height-SDS (r = 0.44, P < .001) and weight-SDS (r = 0.35, P = .002); no significant correlations were found in the placebo group. No serious adverse events were reported during the study.

CONCLUSIONS

Nutritional intervention with the formula was found to be a feasible, effective, and safe approach for promoting the physical growth of short and lean prepubertal children.

Nutritional deficiencies in the pediatric age group in a multicultural developed country, Israel

Nutrient deficiencies are prevalent worldwide. Diseases and morbid conditions have been described to result from nutritional deficiencies. It is essential to address nutrient deficiencies as these may lead to chronic long-term health problems such as rickets, iron deficiency anemia, goiter, obesity, coronary heart disease, type 2 diabetes, stroke, cancer and osteoporosis. In the present review we surveyed the extent and severity of nutritional deficiencies in Israel through a selective and comprehensive Medline review of previous reports and studies performed during the last 40 years. Israeli populations have multiple nutritional deficiencies, including iron, calcium, zinc, folic acid, and vitamins B12, C, D and E, spanning all age groups, several minorities, and specific regions. In Israel, some of the nutrients are mandatorily implemented and many of them are implemented voluntarily by local industries. We suggest ways to prevent and treat the nutritional deficiencies, as a step to promote food fortification in Israel.

Skeletal growth and the changing genetic landscape during childhood and adulthood

Growth, development, and decline of the human skeleton are of central importance to physical anthropology. All processes of skeletal growth (longitudinal growth as well as gains and losses of bone mass) are subjected to environmental and genetic influences. These influences, and their relative contributions to the phenotype, can be asserted at any stage of life. We present here the gross phenotypic and genetic landscapes of four skeletal traits, and show how they vary across the life span. Phenotypic sex differences are found in bone diameter and cortical index (a ratio of cortical thickness over bone diameter) at a very early age and continue throughout most of life. Sexual dimorphism in summed cortical thickness and bone length, however, is not evident until shortly after the pubertal growth spurt. Genetic contributions (heritability) to these skeletal phenotypes are generally moderate to high. Bone length and bone diameter (which both scale with body size) tend to have the highest heritability, with heritability of bone length fairly stable across ages (with a notable dip in early childhood) and that of bone diameter peaking in early childhood. The bone traits summed cortical thickness and cortical index that may better reflect bone mass, a more plastic phenomenon, have slightly lower genetic influences, on average. Results from our phenotypic and genetic landscapes serve three key purposes: 1) demonstration of the integrated nature of the genetic and environmental underpinnings of skeletal form, 2) identification of periods of bone's relative sensitivity to genetic and environmental influences, 3) and stimulation of hypotheses predicting the effects of exposure to environmental variables on the skeleton, given variation in the underlying genetic architecture.

Growth-inhibiting conditions slow growth plate senescence

The mammalian growth plate undergoes programmed senescence during juvenile life, causing skeletal growth to slow with age. We previously found that hypothyroidism in rats slowed both growth plate chondrocyte proliferation and growth plate senescence, suggesting that senescence is not dependent on age per se but rather on chondrocyte proliferation. However, one alternative explanation is that the observed slowing of growth plate senescence is a specific consequence of hypothyroidism. We reasoned that, if delayed senescence is a general consequence of growth inhibition, rather than a specific result of hypothyroidism, then senescence would also be slowed by other growth-inhibiting conditions. In this study, we therefore used tryptophan deficiency to temporarily inhibit growth in newborn rats for 4 weeks. We then allowed the animals to recover and studied the effects on growth plate senescence. We found that structural, functional, and molecular markers of growth plate senescence were delayed by prior tryptophan deficiency, indicating that the developmental program of senescence had occurred more slowly during the period of growth inhibition. Taken together with previous studies in hypothyroid rats, our findings support the hypothesis that delayed senescence is a general consequence of growth inhibition and hence that growth plate senescence is not simply a function of time per se but rather depends on growth.

Cord blood adiponectin and infant growth at one year

OBJECTIVE

The aim of this study was to determine the association between cord blood adiponectin and leptin and early infant growth at one year in small for gestational age (SGA) and appropriate for gestational age (AGA) infants.

STUDY DESIGN

In this prospective study adiponectin and leptin concentrations were determined in cord blood of (i) AGA newborns (n = 44) and (ii) SGA newborns (n = 24). At one year of age, height and weight were measured. Linear regression analysis was used to determine which factors were associated with anthropometric measurements at the age of one year.

RESULTS

(i) SGA neonates had a significantly lower median cord blood adiponectin and leptin than AGA neonates; (ii) among SGA neonates, cord blood adiponectin concentrations were negatively correlated with body weight at one year, weight gain after one year and with BMI at one year; and (iii) among AGA neonates cord blood adiponectin concentrations were negatively correlated with body weight at one year, weight gain after one year and with BMI at one year.

CONCLUSION

The disparity in cord blood adiponectin and leptin concentrations between SGA and AGA neonates suggests a role for adipokines in fetal growth.