Growth Patterns in Small for Gestational Age Babies and Correlation with Insulin-like Growth Factor-1 Levels

Growth hormone treatment does not to lead to insulin resistance nor excessive rise in IGF-1 levels, while improving height in patients small for gestational age A long-term observational study

OBJECTIVE

In children born small for gestational age (SGA), the relationship between growth hormone (GH) treatment and insulin resistance (IR) has only been investigated for a short period, necessitating a longer observation period. This study aimed to evaluate the long-term (10 years) effect of GH to SGA-children on IR and safety during treatment.

DESIGN

This was a multicenter observational study.

PATIENTS

SGA-children who received GH treatment in Spain (stratified by Tanner-stage and age at GH onset [two groups: ≤6 years old or >6 years old]).

MEASUREMENTS

The analysed variables (yearly measures) included auxologic, metabolic (insulin-like growth factor-1 (IGF-1), height velocity [HV], weight and homeostatic model assessment-IR [HOMA-IR]) and safety data. Data were collected prospectively (since the study approval: 2007) and retrospectively (since the initiation of GH treatment: 2005-2007).

RESULTS

A total of 389 SGA children (369 Tanner-I) were recruited from 27 centres. The mean age (standard deviation) of the children at GH treatment onset was 7.2 (2.8) years old. IGF-1 (standard deviation score [SDS]) and HOMA-IR values tended to increase until the sixth year of GH-treatment, with significant differences being observed only during the first year, while these remained stable in the later years (within normal ranges). Height (SDS) increased significantly (basal: -3.0; tenth year: -1.13), and the maximum HV (SDS) occurred during the first year (2.75 ± 2.39).

CONCLUSIONS

HOMA-IR values increased significantly in SGA-children during the first year of GH-treatment, remained stable and were within normal ranges in all cases. Our 10-year data suggests that long-term GH treatment does not promote IR and is well-tolerated, safe and effective.

Percentile-Based Reference Values of Umbilical Cord Blood Insulin-like Growth Factor 1 in Japanese Newborns

We aimed to create percentile-based reference values of the umbilical cord blood insulin-like growth factor-1 (IGF-1) levels in Japanese newborns, as these values have not yet been established. A total of 259 newborns were classified into four gestational-age-at-birth (GA) groups: extremely preterm (<28 weeks); early preterm (28−33 weeks); late preterm (34−36 weeks); and term (≥37 weeks). They were further subclassified as small-for-gestational-age (SGA) or non-SGA. The 10th, 25th, 50th, 75th, and 90th percentiles of the umbilical cord blood IGF-1 levels were calculated and compared between the groups by using reference values of 9, 18, 33, 52, and 71 ng/mL, respectively. In the extremely preterm group, the IGF-1 levels were significantly lower than those in the early preterm, late preterm, and term groups (13.5, 24.0, 44.5, and 47.5 ng/mL, respectively; p < 0.001). The umbilical cord blood IGF-1 levels in the SGA newborns were significantly lower than those in the non-SGA newborns in all subgroups. In multivariate analyses, the GA and birth weight standard deviation scores were independent determinant factors for the umbilical cord blood IGF-1 levels. Thus, we established percentile-based reference values of umbilical cord blood IGF-1 in Japanese newborns; these reference values can be applied on the basis of the extent of prematurity and the SGA status.

The degree of maternal nutrient restriction during late gestation influences the growth and endocrine profiles of offspring from beef cows

ContextCow–calf operations in Argentina are managed under extensive grazing condition and the quality of forages is often poor during the second half of gestation. The severity of nutrient restriction in bovine gestation, caused by seasonal pasture production, often results in poor production traits in progeny.AimsThe objective of the current study was to determine whether different levels of maternal nutrient intake in beef cows during late gestation affect fetal and postnatal growth, glucose metabolism, and insulin-like growth factor 1 (IGF1) concentrations in offspring of beef cattle.MethodsAt 180±4 days of gestation, multiparous Angus cows (n=56) were blocked by bodyweight (BW) and expected calving date, and assigned to pens (2 or 3 cows/pen). Pens (n=8 per treatment) were then randomly assigned to the following treatments: severely restricted (SR; 50% of net energy and 58% of CP requirements), moderately restricted (MR; 75% of net energy and 85% of CP requirements), or control (CON; 100% of net energy and 116% of CP requirements). Pen was the experimental unit and data were analysed by ANOVA or repeated measures analysis, as appropriate. After calving, all cows were managed in a single group until weaning.Key resultsCow BW and body condition score decreased as nutritional restriction increased (P&lt;0.05). At parturition, birth weight of calves from SR dams and MR dams was lower than that of calves from CON dams (P=0.05; 4.9kg and 2.1kg respectively). Average daily gain of calves from birth to 24 days of age was higher (P=0.01) in calves from SR dams than in calves from CON and MR dams. Calves from MR dams were lighter (P=0.04) than were calves from SR and CON dams at weaning. Treatments did not affect milk production or composition (P&gt;0.10) or glucose–insulin metabolism of offspring during lactation (P&gt;0.10). Concentration of IGF1 tended to be lower in MR progeny than in SR and CON progeny during lactation (P=0.09).ConclusionsLate gestation maternal nutrient restriction, irrespective of the severity of the restriction, decreased birth weight of offspring; however, severe nutrient restriction induced early postnatal compensatory growth.ImplicationsThe severe nutritional restriction produced calves with weaning weights indistinguishable from the control cows due to early postnatal compensatory growth. However, the longer-term effects of nutritional restriction of the dam in the second half of pregnancy on metabolic and reproductive performance in replacement heifers or meat production/quality in steers is yet to be determined.

Association of preeclampsia with anthropometric measures and blood pressure in Indian children

BACKGROUND AND OBJECTIVE

Birth weight and post-natal growth are important predictors of adult health. Preeclampsia (PE) is associated with low birth weight and may have long term effects on the health of the children. The current study aims to compare anthropometry and blood pressure between children of mothers with and without PE in an Indian cohort.

METHODS

We studied children born to women with (PE; n = 211) and without preeclampsia (non-PE; n = 470) at Bharati Hospital, Pune, India. Anthropometry and blood pressure were measured in children at 3-7 years of age. Weight and height Z-scores were calculated using the WHO 2006 growth reference. Independent t-tests were used to compare means between the two groups, and associations between preeclampsia and child outcomes were analyzed using multiple linear regression, adjusting for potential confounders.

RESULTS

Weight and height Z-scores (p = 0.04 and 0.008), and subscapular skinfold thickness (p = 0.03) were higher among children of PE compared with children of non-PE mothers. Systolic blood pressure was also higher in children of PE mothers (1.70 mmHg [95% CI 0.05, 2.90] p = 0.006). BMI and diastolic blood pressure did not differ between groups. In regression models adjusted for newborn weight and gestational age, current age and sex, and maternal height, BMI and socio-economic status, children of PE mothers had higher weight Z-score (0.27 SD [95%CI 0.06, 0.48] p = 0.01), height Z-score (0.28 SD [95%CI 0.09, 0.47] p = 0.005), and subscapular skinfold thickness (0.38 mm [95%CI 0.00, 0.76] p = 0.049). A trend for higher systolic blood pressure (1.59 mmHg [95%CI -0.02, 3.20] p = 0.053) in the children was also observed in the adjusted model. The difference in systolic blood pressure was attenuated after adjusting further for the child's weight and height (1.09 mmHg [95%CI -0.48, 2.67] p = 0.17). There was no evidence of differences in effects between boys and girls.

CONCLUSION

Children of PE mothers were taller and heavier, and had higher systolic blood pressure, partly explained by their increased body size, than children of non-PE mothers. In utero exposure to preeclampsia may increase the risk of future cardiovascular disease.

The Role of Prenatal Melatonin in the Regulation of Childhood Obesity

There is a growing awareness that pregnancy can set the foundations for an array of diverse medical conditions in the offspring, including obesity. A wide assortment of factors, including genetic, epigenetic, lifestyle, and diet can influence foetal outcomes. This article reviews the role of melatonin in the prenatal modulation of offspring obesity. A growing number of studies show that many prenatal risk factors for poor foetal metabolic outcomes, including gestational diabetes and night-shift work, are associated with a decrease in pineal gland-derived melatonin and associated alterations in the circadian rhythm. An important aspect of circadian melatonin’s effects is mediated via the circadian gene, BMAL1, including in the regulation of mitochondrial metabolism and the mitochondrial melatoninergic pathway. Alterations in the regulation of mitochondrial metabolic shifts between glycolysis and oxidative phosphorylation in immune and glia cells seem crucial to a host of human medical conditions, including in the development of obesity and the association of obesity with the risk of other medical conditions. The gut microbiome is another important hub in the pathoetiology and pathophysiology of many medical conditions, with negative consequences mediated by a decrease in the short-chain fatty acid, butyrate. The effects of butyrate are partly mediated via an increase in the melatoninergic pathway, indicating interactions of the gut microbiome with melatonin. Some of the effects of melatonin seem mediated via the alpha 7 nicotinic receptor, whilst both melatonin and butyrate may regulate obesity through the opioidergic system. Oxytocin, a recently recognized inhibitor of obesity, may also be acting via the opioidergic system. The early developmental regulation of these processes and factors by melatonin are crucial to the development of obesity and many diverse comorbidities.

Abundances of placental imprinted genes CDKN1C, PHLDA2 and IGF-2 are related to low birth weight and early catch-up growth in full-term infants born small for gestational age

Children born small for gestational age (SGA) generally have a catch-up growth and rapid weight gain in the first years of life, which is a high risk of insulin resistance and cardiovascular diseases later in life. It was reported that the level of imprinted genes IGF-2, CDKN1C and PHLDA2 regulates placental growth. We assessed these imprinted genes expression levels in placental tissue and their influences on catch-up growth of full-term SGA infants. The protein and mRNA levels of placental CDKN1C, PHLDA2 and IGF-2 were analyzed in 29 full-term SGA and 29 full-term infants born appropriate for gestational age (AGA) using quantitative RT-PCR and Western blot assay, respectively. Catch-up growth was indicated by increased standard deviation score (ΔSDS) of weight at 1, 3 and 6 months relative to birth weight (BW). Correlations between indicated variables were evaluated using Pearson correlation coefficient analysis. Compared to AGA infants, CDKN1C and PHLDA2 levels were significantly increased, whereas IGF-2 was significantly reduced in SGA infants. The value of ΔSDS was significantly higher in SGA than that in AGA infants. For SGA status, Pearson analysis shows i) a negative correlation of CDKN1C and PHLDA2 abundances with BW, and a positive correlation of IGF-2 with BW, ii) no correlation between the three imprinted gene abundances and placental weight (PW), and between PW and BW, iii) a positive correlation of PHLDA2 abundance with CDKN1C, and iv) a positive correlation of CDKN1C and PHLDA2 abundances with ΔSDS, and a negative correlation of IGF-2 with ΔSDS at 1, 3 and 6 months. Taken together, increased CDKN1C and PHLDA2 and reduced IGF-2 abundances in placental tissue were related to BW and early period catch-up growth in full-term SGA infants. Placental CDKN1C, PHLDA2 and IGF-2 level monitoring may be useful for predicting and preventing the development of SGA.