GLP-1 and IGF-I levels are elevated in late infancy in low birth weight infants, independently of GLP-1 receptor polymorphisms and neonatal nutrition

Relationship of Glucagon-like Peptide 1 and Peptide YY with Catch-up Growth in Children Born Small for Gestational Age

Objective

Children born small for gestational age (SGA) are at a greater risk of developing insulin resistance, type 2 diabetes, and cardiovascular disease in adulthood. Gastrointestinal peptides, some secreted by intestinal L cells, regulate glucose and lipid metabolism and act on the hypothalamus to regulate energy homeostasis. The aim of this study was to explore whether gastrointestinal peptides are involved in metabolic disorders in SGA, which remains unclear.

Methods

The secretion of glucagon-like peptide 1 (GLP-1) and peptide YY (PYY) were investigated in prepubertal children born SGA, the differences between catch-up growth and persistent short stature were compared, and correlation with glucose and lipid metabolism was analyzed. GLP-1, PYY, insulin-like growth factor 1, glucose, insulin, and lipid concentrations were analyzed in prepubertal children aged 4-10 years, stratified into three groups: short-SGA (SGA-s), catch-up growth SGA, and normal growth appropriate for gestational age (AGA).

Results

Fasting GLP-1 and PYY concentrations were significantly lower in the SGA group than in the AGA group (p<0.05), and the GLP-1 level in infants born SGA with catch-up growth was lower than that in the SGA-s group (p<0.05). In the SGA population, GLP-1 showed a weak negative correlation with catch-up growth (r=-0.326) and positive correlation with fasting insulin (r=0.331).

Conclusion

Lower GLP-1 concentrations may be associated with abnormal glucose metabolism in prepubertal children born SGA with catch-up growth. This is indirect evidence that impaired intestinal L cell function may be involved in the development of metabolic complications in SGA children.

No effect of multi-strain probiotic supplementation on metabolic and inflammatory markers and newborn body composition in pregnant women with obesity: Results from a randomized, double-blind placebo-controlled study

BACKGROUND AND AIMS

Modulation of the gut microbiome composition with probiotics may have beneficial metabolic effects in pregnant women with obesity. The aim was to investigate the effect of probiotic supplementation during pregnancy on metabolic and inflammatory markers and the body composition of the offspring.

METHODS AND RESULTS

A randomized double-blind trial in 50 pregnant women (pre-pregnancy BMI ≥30 and < 35 kg/m2) comparing multi-strain probiotics (Vivomixx®; 450 billion CFU/d) versus placebo from 14 to 20 weeks of gestation until delivery was carried out. Participants were followed with two predelivery visits at gestational week 27-30 and 36-37 and with one postdelivery visit. All visits included fasting blood samples (C-reactive protein (CRP), alanine aminotransferase (ALT), aspartate aminotransferase (AST), insulin, C-peptide, glucose, glucagon, and glucagon-like peptide-1 (GLP-1)). At delivery, umbilical cord blood samples were collected (GLP-1 and glucagon). At the postdelivery visit, a dual-energy X-ray absorptiometry (DXA) scan of the newborn was performed. Forty-nine of 50 participants completed the study until delivery, and 36 mother-offspring dyads underwent postdelivery examinations including a DXA scan. There were no significant differences in changes in measured biomarkers between the probiotic versus the placebo group. No differences were found in newborn body composition or GLP-1 and glucagon. GLP-1 measured in umbilical blood samples was positively correlated to fat percent in offspring from the probiotic group.

CONCLUSION

In this study of pregnant women with obesity and their newborns, there was no effect of probiotic supplementation in mothers or babies on metabolic or inflammatory biomarkers or on body composition of offspring. This study was registered at clinicaltrials.gov as NCT02508844.

Circulating exosomes decrease in size and increase in number between birth and age 7: relations to fetal growth and liver fat

Purpose

Exosomes play a key role in cell-to-cell communication by transferring their cargo to target tissues. Little is known on the course of exosome size and number in infants and children.

Methods

Longitudinally, we assessed the size and number of circulating exosomes at birth and at ages 2 and 7 yr in 75 infants/children born appropriate-for-gestational-age (AGA; n=40) or small-for-gestational-age (SGA; n=35 with spontaneous catch-up), and related those results to concomitantly assessed measures of endocrine-metabolic health (HOMA-IR; IGF-1), body composition (by DXA at ages 0 and 2) and abdominal fat partitioning (subcutaneous, visceral and hepatic fat by MRI at age 7).

Results

Circulating exosomes of AGAs decreased in size (on average by 4.2%) and increased in number (on average by 77%) between birth and age 7. Circulating exosomes of SGAs (as compared to those of AGAs) had a larger size at birth [146.8 vs 137.8 nm, respectively; p=0.02], and were in lower number at ages 2 [4.3x1011 vs 5.6x1011 particles/mL, respectively; p=0.01] and 7 [6.3x1011 vs 6.8x1011 particles/mL, respectively; p=0.006]. Longitudinal changes were thus more pronounced in SGAs for exosome size, and in AGAs for exosome number. At age 7, exosome size associated (P<0.0001) to liver fat in the whole study population.

Conclusion

Early-life changes in circulating exosomes include a minor decrease in size and a major increase in number, and these changes may be influenced by fetal growth. Exosome size may become one of the first circulating markers of liver fat in childhood.

Circulating progranulin in human infants: relation to prenatal growth and early postnatal nutrition

BACKGROUND

Progranulin (PGRN) displays pleiotropic biological functions and has been proposed as a biomarker for metabolic diseases. We longitudinally assessed PGRN concentrations in infants born appropriate (AGA) or small for gestational age (SGA), the latter being at risk for obesity and type 2 diabetes, especially if they experience an excessive postnatal catch-up in weight and are formula-fed (FF).

METHODS

The study population consisted of 183 infants who were exclusively breast-fed [(BF), AGA, n = 66; SGA, n = 40], or FF (AGA, n = 31; SGA, n = 46) over the first 4 months. Assessments included auxology, fasting glucose, insulin, IGF-1, high-molecular-weight adiponectin, PGRN and body composition (by DXA), at birth, and at age 4 and 12 months.

RESULTS

PGRN levels were low at birth and unaffected by prenatal growth. PGRN increased at 4 and 12 months, although to a lesser extent in SGA infants, and was unrelated to the mode of feeding. PGRN correlated with markers of adiposity, inflammation and insulin resistance in both AGA and SGA infants, especially in those FF.

CONCLUSIONS

The attenuated increase of PGRN levels in SGA infants over the first year of life, along with the association to markers of unhealthy metabolic profile, might point to a role of PGRN in future disease risks.

IMPACT

Progranulin (PGRN) displays pleiotropic biological functions and has been proposed as a biomarker for metabolic diseases. In healthy infants, PGRN concentrations are low at birth and experience a significant and progressive increase up to age 12 months, which is less marked in infants born small for gestational age (SGA) and is unrelated to the mode of feeding. Circulating PGRN is related to markers of adiposity, inflammation, and insulin sensitivity, especially in formula-fed SGA infants. PGRN may play a role in the metabolic adaptations of SGA infants during early life, potentially contributing to the risk for obesity and type 2 diabetes in this population.

Increased liver fat associates with severe metabolic perturbations in low birth weight men

OBJECTIVE

Ectopic liver fat deposition, resulting from impaired subcutaneous adipose tissue expandability, may represent an age-dependent key feature linking low birth weight (LBW) with increased risk of type 2 diabetes (T2D). We examined whether presumably healthy early middle-aged, non-obese LBW subjects exhibit increased liver fat content, whether increased liver fat in LBW is associated with the severity of dysmetabolic traits and finally whether such associations may be confounded by genetic factors.

METHODS

Using 1H magnetic resonance spectroscopy, we measured hepatic fat content in 26 early middle-aged, non-obese LBW and 22 BMI-matched normal birth weight (NBW) males. Endogenous glucose production was measured by stable isotopes, and a range of plasma adipokine and gut hormone analytes were measured by multiplex ELISA. Genetic risk scores were calculated from genome-wide association study (GWAS) data for birth weight, height, T2D, plasma cholesterol and risk genotypes for non-alcoholic fatty liver disease (NAFLD).

RESULTS

The LBW subjects had significantly increased hepatic fat content compared with NBW controls (P= 0.014), and 20% of LBW vs no controls had overt NAFLD. LBW subjects with NAFLD displayed widespread metabolic changes compared with NBW and LBW individuals without NAFLD, including hepatic insulin resistance, plasma adipokine and gut hormone perturbations as well as dyslipidemia. As an exception, plasma adiponectin levels were lower in LBW subjects both with and without NAFLD as compared to NBW controls. Genetic risk for selected differential traits did not differ between groups.

CONCLUSION

Increased liver fat content including overt NAFLD may be on the critical path linking LBW with increased risk of developing T2D in a non-genetic manner.

Circulating growth-and-differentiation factor-15 in early life: relation to prenatal and postnatal growth and adiposity measurements

BACKGROUND

Growth-and-differentiation-factor-15 (GDF15) is a regulator of energy homeostasis. To determine the relationship between circulating GDF15 and parameters of metabolic health, we assessed longitudinally GDF15 concentrations in infants born either appropriate- (AGA) or small-for-gestational-age (SGA), the latter population known to be at risk for metabolic alterations, particularly after a rapid postnatal catch-up in weight.

METHODS

The study cohort consisted of 103 infants (70 AGA and 33 SGA). Assessments included body length, weight, and ponderal index (PI); fasting glucose, insulin, IGF-I, high-molecular-weight adiponectin, GDF15; and body composition (by absorptiometry) at birth, and at age 4, 12 and 24 months.

RESULTS

GDF15 levels at birth were significantly higher than those at each subsequent time point and were similar in AGA and SGA subjects. GDF15 concentrations dropped at age 4 months, more substantially in SGA infants, and continued to decline in both subgroups reaching adult concentrations by age 24 months. GDF15 levels correlated inversely with the changes in PI, IGF-I and body fat throughout follow-up.

CONCLUSIONS

Early life is associated with supra-adult concentrations of GDF15. The lower levels of GDF15 in SGA subjects may be an adaptive mechanism to promote catch-up in weight and might increase the risk for obesity later in life.