Prematurity and low birth weight lead to altered bone geometry, strength, and quality in children

Bone Turnover Markers during Growth Hormone Therapy for Short Stature Children Born Small for Gestational Age

Growth hormone therapy (GHT) can improve growth velocity and final height, but can also accelerate the process of bone growth, which is related to structural bone modeling in both formation and resorption. This study evaluated the capacity of bone turnover markers to predict early growth response to one year of GHT in short stature children born small for gestational age (SGA). This study included 25 prepubertal children born SGA. We estimated P1NP (N-terminal procollagen type 1), CTX (C-terminal telopeptide of collagen type 1), P3NP (N-terminal procollagen type 3), NT-pro-CNP (amino-terminal C-type natriuretic peptide) and Ca-P metabolism using standard ECLIA (electrochemiluminescence), RIA (radioimmunoassay), and ELISA (enzyme-linked immunosorbent assay) methods. A statistically significant increase in bone resorption markers (CTX) was found at both 6 and 12 months. P1NP bone markers were increased at 6 months and after 12 months of therapy. The P3NP marker for collagen synthesis also increased after 12 months of therapy. We obtained significant increases in phosphorus levels at 6 and 12 months, and similar ALP (alkaline phosphatase) increases. We found a significant correlation between height (cm) and CTX after 6-12 months, as well as a P1NP/height (SD) correlation after 12 months. Calcium levels significantly correlated with height (SD) after 12 months. We found strong reactions of bone resorption and bone formation markers during growth hormone therapy, which may determine their selection as predictors of GHT outcome in children born SGA. However, the issue requires further research.

Comparison of anthropometric, metabolic, and body compositional abnormalities in Korean children and adolescents born small, appropriate, and large for gestational age: a population-based study from KNHANES V (2010-2011)

PURPOSE

The impacts of growth restriction and programming in the fetal stage on metabolic and bone health in children and adolescents are poorly understood. Moreover, there is insufficient evidence for the relationship between current growth status and metabolic components. Herein, we compared the growth status, metabolic and body compositions, and bone mineral density in Korean children and adolescents based on birth weight at gestational age.

METHODS

We studied 1,748 subjects (272 small for gestational age [SGA], 1,286 appropriate for gestational age [AGA], and 190 large for gestational age [LGA]; 931 men and 817 women) aged 10-18 years from the Korean National Health and Nutrition Examination Survey (KNHANES) V (2010-2011). Anthropometric measurements, fasting blood biochemistry, and body composition data were analyzed according to birth weight and gestational age.

RESULTS

The prevalence of low birth weight (14.7% vs. 1.2% in AGA and 3.2% in LGA, p<0.001) and current short stature (2.237 [1.296-3.861] compared to AGA, p=0.004) in SGA subjects was greater than that in other groups; however, the prevalence of overweight and obesity risks, metabolic syndrome (MetS), and MetS component abnormalities was not. Moreover, no significant differences were found in age- and sex-adjusted lean mass ratio, fat mass ratio, truncal fat ratio, bone mineral content, or bone density among the SGA, AGA, and LGA groups in Korean children and adolescents.

CONCLUSION

Our data demonstrate that birth weight alone may not be a determining factor for body composition and bone mass in Korean children and adolescents. Further prospective and longitudinal studies in adults are necessary to confirm the impact of SGA on metabolic components and bone health.

Developmental factors influencing bone strength in precocial mammals: An infant pig model

Most vertebrates are precocial in locomotion, able to walk and run soon after birth. Precociality requires a bony skeleton of sufficient strength to resist mechanical loading during early locomotor efforts. The aim of this study was to use an animal model-the preterm infant pig-to investigate some of the proximate factors that might determine variation in bone strength in precocial animals. Based on the prior literature, we tested the null predictions that skeletal integrity would be significantly compromised by truncated gestation (i.e., preterm birth) and reduced body mass at birth. We generated a suite of both morphometric measures (tissue mineral density and cross-sectional geometry) and performance-related metrics (ability to resist loading, deformation, and fracture during three-point bending tests) of the appendicular skeleton of preterm and full-term infant pigs. Results showed that very few measures in our ontogenetic infant pig sample significantly varied with either gestation length or birth mass. Overall, our results contribute to a growing body of literature demonstrating the early functional capacity of the precocial infant musculoskeletal system and suggest that bone strength in perinatal precocial mammals may be robust to the factors shown to compromise skeletal integrity in more altricial taxa.

Impact of quorum sensing signaling molecules in gram-negative bacteria on host cells: current understanding and future perspectives

Quorum sensing is a molecular signaling-based communication mechanism in prokaryotes. In the basic mode, signaling molecules released by certain bacteria are sensed by intracellular receptors or membrane-bound receptors of other members in the community, leading to the collective isogenic signaling molecule synthesis and synchronized activities. This regulation is important for the symbiosis of the bacterium with the host, as well as virulence and biofilm formation. Notably, quorum sensing signaling molecules are not only able to control microbial community behavior but can likewise regulate the physiological status of host cells. Here, we provide a comprehensive review of the importance of quorum sensing signaling molecules in gram-negative bacteria in regulating host cell function and gut health, and suggest possible opportunities for application in combating human and animal diseases by blocking the pathways through which quorum sensing signaling molecules exert their functions.

Bone density and body composition in small for gestational age children with adequate catch up growth: A preliminary retrospective case control study

BACKGROUND

Fetal growth patterns and birth weight (BW) have been associated with bone mineral density (BMD) and content (BMC) throughout infancy and childhood up to early adulthood. We hypothesized that in small for gestational age (SGA) children, compensatory infant catch-up growth to normal height centiles counteracts the adverse consequences of low BW on bone accrual.

AIM

To evaluate BMD and BMC of SGA children born at term who experienced a normal catch-up growth as compared to children born appropriate for gestational age (AGA).

PATIENTS

We recruited 53 SGA (26 females) and 60 AGA children (27 females), aged 6 to 18 years, matched for sex and body mass index (BMI). Fat mass (FM); Free fat mass (FFM); Lumbar spine and Total body less head (TBLH) BMD; BMC and BMD standard deviation scores corrected for body size (BMAD, BMAD z-score and TBLH BMD/Height) and TBLH BMC for FFM (TBLHBMC/FFM) were derived from Dual Energy X-ray absorptiometry (DXA) scans.

RESULTS

SGA and AGA children did not differ in any auxological, body composition and bone parameters appropriately adjusted for height and FFM. BMI, FM and, remarkably, FFM were significantly correlated with bone mass parameters in both groups while no correlation was found between FM and FFM with the BW SDS in the univariate analysis.

CONCLUSION

Our preliminary data demonstrate that SGA children born at term who recover from their growth deficiency through catch-up growth achieve bone mass and body composition not different from children born AGA.

Original low birth weight deteriorates the hindgut epithelial barrier function in pigs at the growing stage

The deteriorative effect of low birth weight (LBW) on the mucosal permeability of the small intestine in piglets has been widely confirmed. However, whether the hindgut epithelial barrier function in LBW pigs is deteriorated during the growing stage is still unclear. Our study investigated differences in the hindgut epithelial barrier function between LBW and normal birth weight pigs during the growing stage (d 90). Our data demonstrated that the hindgut epithelium of LBW pigs has a high histopathological score, accompanied by decreased antioxidant capacity and increased apoptosis rate, as well as elevated expression and activity of caspase-3. In addition, the number of intestinal goblet cells and gene expression of mucin 2 were significantly down-regulated in LBW pigs. The expression of tight junction proteins (ZO-1 and occludin) was markedly inhibited by the LBW. The mRNA abundance of inflammatory cytokines such as TNF-α, IL-1β, and IL-8 was significantly increased in the hindgut mucosa of LBW pigs. Furthermore, our data revealed that LBW altered the intestinal microbial community in the hindgut mucosa of pigs. Collectively, these finding add to our understanding of the mechanisms responsible for hindgut epithelial barrier dysfunction in LBW pigs during the growing stage and facilitate the development of nutritional intervention strategies.-Tao, S., Bai, Y., Li, T., Li, N., Wang, J. Original low birth weight deteriorates the hindgut epithelial barrier function in pigs at the growing stage.

Developmental Programming of Body Composition: Update on Evidence and Mechanisms

PURPOSE OF REVIEW

A growing body of epidemiological and experimental data indicate that nutritional or environmental stressors during early development can induce long-term adaptations that increase risk of obesity, diabetes, cardiovascular disease, and other chronic conditions-a phenomenon termed "developmental programming." A common phenotype in humans and animal models is altered body composition, with reduced muscle and bone mass, and increased fat mass. In this review, we summarize the recent literature linking prenatal factors to future body composition and explore contributing mechanisms.

RECENT FINDINGS

Many prenatal exposures, including intrauterine growth restriction, extremes of birth weight, maternal obesity, and maternal diabetes, are associated with increased fat mass, reduced muscle mass, and decreased bone density, with effects reported throughout infancy and childhood, and persisting into middle age. Mechanisms and mediators include maternal diet, breastmilk composition, metabolites, appetite regulation, genetic and epigenetic influences, stem cell commitment and function, and mitochondrial metabolism. Differences in body composition are a common phenotype following disruptions to the prenatal environment, and may contribute to developmental programming of obesity and diabetes risk.

Maternal hyperuricemia superimposed on maternal hypertension aggravates the risk of small-for-gestational-age fetus

AIMS

Small-for-gestational-age (SGA) fetus is an important public health issue because of its high mortality and long-term effects on health. Maternal hyperuricemia is associated with diverse adverse pregnant outcomes and neonatal disturbance. We aimed to evaluate whether maternal hyper-uric acid (HUA) is associated with the risk of SGA fetus and to explore whether it can modify the association between maternal hyper-blood pressure (HBP) and SGA fetus.

MATERIALS AND METHODS

We performed a population-based cross-section retrospective study, a total of 6715 pregnant females were recruited. Multiple logistic regression analysis was performed to identify risk factors significantly correlated with SGA fetus, and then studied the effect of maternal HUA on the association between maternal HBP and SGA fetus.

KEY FINDINGS

We collected 537 SGA fetuses among 6715 pregnant females. Maternal HUA was an independent risk factor for SGA delivery (odds ratio (OR), 2.737; 95% confidence interval (CI), 2.110-3.551). A dose-response association between maternal uric acid and SGA delivery was found among normotensive and hypertensive group. Compared with those whose uric acid was lower than 270 μmo/L with normal-blood pressure (NBP), the risk for SGA delivery in those whose uric acid was higher than 370 μmo/L with stage 2 or 3 hypertension increased 12.695-fold.

SIGNIFICANCE

Our results suggest that maternal HUA could increase the risk of neonatal SGA, and maternal HUA could be superimposed upon pre-existing maternal HBP and increase the risk for SGA fetus.

Mineral Homeostasis and Effects on Bone Mineralization in the Preterm Neonate

Most bone formation and mineralization occurs late in gestation. Accretion of adequate minerals is a key element of this process and is often interrupted through preterm birth. In utero, mineral transport is accomplished via active transport across the placenta and does not require fetal hormone input. Postnatal mineral homeostasis requires a balance of actions of parathyroid hormone, calcitonin, and vitamin D on target organs. Preterm birth, asphyxia, acidosis, and prolonged parenteral nutrition increase the risk of mineral imbalance and metabolic bone disease (MBD). Aggressive postnatal nutrition is key to preventing and treating MBD in preterm infants.

Nutritional support for low birth weight infants: insights from animal studies

Infants born with low birth weights (<2500 g, LBW), accounting for about 15 % of newborns, have a high risk for postnatal growth failure and developing the metabolic syndromes such as type 2 diabetes, CVD and obesity later in life. Improper nutrition provision during critical stages, such as undernutrition during the fetal period or overnutrition during the neonatal period, has been an important mediator of these metabolic diseases. Considering the specific physiological status of LBW infants, nutritional intervention and optimisation during early life merit further attention. In this review, the physiological and metabolic defects of LBW infants were summarised from a nutritional perspective. Available strategies for nutritional interventions and optimisation of LBW infants, including patterns of nutrition supply, macronutrient proportion, supplementation of amino acids and their derivatives, fatty acids, nucleotides, vitamins, minerals as well as hormone and microbiota manipulators, were reviewed with an aim to provide new insights into the advancements of formulas and human-milk fortifiers.

Placental Size Is Associated Differentially With Postnatal Bone Size and Density

We investigated relationships between placental size and offspring adolescent bone indices using a population-based, mother-offspring cohort. The Avon Longitudinal Study of Parents and Children (ALSPAC) recruited pregnant women from the southwest of England between 1991 and 1993. There were 12,942 singleton babies born at term who survived at least the first 12 months. From these, 8933 placentas were preserved in formaldehyde, with maternal permission for their use in research studies. At the approximate age of 15.5 years, the children underwent a dual-energy X-ray absorptiometry (DXA) scan (measurements taken of the whole body minus head bone area [BA], bone mineral content [BMC], and areal bone mineral density [aBMD]). A peripheral quantitative computed tomography (pQCT) scan (Stratec XCT2000L; Stratec, Pforzheim, Germany) at the 50% tibial site was performed at this visit and at approximately age 17.7 years. In 2010 a sample of 1680 placentas were measured and photographed. To enable comparison of effect size across different variables, predictor and outcome variables were standardized to Z-scores and therefore results may be interpreted as partial correlation coefficients. Complete placental, DXA, and pQCT data were available for 518 children at age 15.5 years. After adjustment for gender, gestational age at birth, and age at time of pQCT, the placental area was positively associated with endosteal circumference (β [95% CI]: 0.21 [0.13, 0.30], p < 0.001), periosteal circumference (β [95% CI]: 0.19 [0.10, 0.27], p < 0.001), and cortical area (β [95% CI]: 0.10 [0.01, 0.18], p = 0.03), and was negatively associated with cortical density (β [95% CI]: -0.11 [-0.20, -0.03], p = 0.01) at age 15.5 years. Similar relationships were observed for placental volume, and after adjustment for additional maternal and offspring covariates. These results suggest that previously observed associations between placental size and offspring bone development persist into older childhood, even during puberty, and that placental size is differentially related to bone size and volumetric density. © 2016 The Authors. Journal of Bone and Mineral Research Published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research (ASBMR).

Effects of Birth Weight on Anterior Segment Measurements in Full-Term Children Without Low Birth Weight by Dual-Scheimpflug Analyzer

PURPOSE

To evaluate the effects of birth weight on ocular anterior segment parameters in full-term children without low birth weight using the Galilei Dual-Scheimpflug Analyzer.

DESIGN

Retrospective cohort study.

METHODS

The right eyes from 110 healthy children, 3-6 years of age, were scanned with the Galilei Dual-Scheimpflug Analyzer. A total of 78 eyes were measured in full-term children with birth weight of >2500 g. Central, paracentral, pericentral, and the thinnest corneal thicknesses; anterior and posterior keratometry (average, steep, flat); axial curvatures; asphericity of cornea; anterior chamber depth and volume; and iridocorneal angle values were measured. Axial length, lens thickness, and vitreous length were obtained by ultrasound biometry.

RESULTS

The mean age of children was 55.86 ± 12.52 (mean ± SD) months. Mean birth weight and gestational age were 3426.3 ± 545 g and 39.4 ± 1.2 weeks, respectively. Although lens thickness, vitreous length, axial length, and anterior chamber volume were moderately correlated with birth weight (P < .05), there was no relationship between birth weight and anterior chamber depth. With the exception of pericentral corneal thickness, all regions of corneal thicknesses were correlated with birth weight (P < .05). Birth weight was negatively correlated with anterior curvature (P < .05) and had no relationship to posterior curvature. While central and paracentral axial curvatures correlated with birth weight (P < .05), pericentral axial curvature did not.

CONCLUSION

Preschoolers who were born heavier had thicker cornea and lens, longer axial length, and flatter corneal curve. The thicknesses and axial curves of central cornea within 7 mm may be particularly associated with birth weight.