Novel bioactive substances in human colostrum: could they play a role in postnatal adaptation?

OBJECTIVE

To determine maternal colostrum/serum concentrations of the bioactive substances irisin, adropin and copeptin and investigate their association with several perinatal parameters and pathologic conditions during pregnancy.

METHODS

In a cohort of 81 mothers with full-term deliveries, colostrum/serum concentrations of irisin, adropin and copeptin were prospectively evaluated by ELISA on Day 3-4 postpartum.

RESULTS

Copeptin and adropin were detectable in human colostrum at higher, while irisin at lower concentrations than in maternal serum (p < 0.001 in all cases). Colostrum adropin and copeptin concentrations positively correlated with maternal serum ones (r = 0.421, p < 0.001 and r = 0.304, p = 0.006, respectively).

CONCLUSIONS

Irisin, adropin and copeptin are present in colostrum and we speculate that they may be implicated in postnatal adaptation with respect to thermoregulation, vascular adaptation, glucose metabolism, lung function and fluid homeostasis. These findings may possibly enhance the necessity for early breastfeeding, particularly of infants born by cesarean section, who are prone to hypothermia, breathing disorders and dehydration.

Higher levels of s-RANKL and osteoprotegerin in children and adolescents with type 1 diabetes mellitus may indicate increased osteoclast signaling and predisposition to lower bone mass: a multivariate cross-sectional analysis

Simultaneous lower bone mineral density, metabolic bone markers, parathyroid hormone (PTH), magnesium, insulin-like growth factor 1 (IGF1), and higher levels of total soluble receptor activator of nuclear factor-kappa B ligand (s-RANKL), osteoprotegerin (OPG), and alkaline phosphatase (ALP) are indicative of lower osteoblast and increased osteoclast signaling in children and adolescents with type 1 diabetes mellitus, predisposing to adult osteopenia and osteoporosis.

INTRODUCTION

Type 1 diabetes mellitus (T1DM) is a risk factor for reduced bone mass, disrupting several bone metabolic pathways. We aimed at identifying association patterns between bone metabolic markers, particularly OPG, s-RANKL, and bone mineral density (BMD) in T1DM children and adolescents, in order to study possible underlying pathophysiologic mechanisms of bone loss.

METHODS

We evaluated 40 children and adolescents with T1DM (mean ± SD age 13.04 ± 3.53 years, T1DM duration 5.15 ± 3.33 years) and 40 healthy age- and gender-matched controls (aged12.99 ± 3.3 years). OPG, s-RANKL, osteocalcin, C-telopeptide cross-links (CTX), IGF1, electrolytes, PTH, and total 25(OH)D were measured, and total body along with lumbar spine BMD were evaluated with dual energy X-ray absorptiometry (DXA). Multivariate regression and factor analysis were performed after classic inference.

RESULTS

Patients had significantly lower BMD, with lower bone turnover markers, PTH, magnesium, and IGF1 than controls, indicating lower osteoblast signaling. Higher levels of total s-RANKL, OPG, and total ALP were observed in patients, with log(s-RANKL) and OPG correlation found only in controls, possibly indicating increased osteoclast signaling in patients. Coupling of bone resorption and formation was observed in both groups. Multivariate regression confirmed simultaneous lower bone turnover, IGF1, magnesium, and higher total s-RANKL, OPG, and ALP in patients, while factor analysis indicated possible activation of RANK/RANKL/OPG system in patients and its association with magnesium and IGF1. Patients with longer disease duration or worse metabolic control had lower BMD.

CONCLUSIONS

T1DM children and adolescents have impaired bone metabolism which seems to be multifactorial. Reduced osteoblast and increased osteoclast signaling, resulting from multiple simultaneous disturbances, could lead to reduced peak bone accrual in early adulthood, predisposing to adult osteopenia and osteoporosis.

Implication of the myokine irisin in maternal energy homeostasis in pregnancies with abnormal fetal growth

OBJECTIVE

To prospectively investigate maternal concentrations of the myokine irisin in large for gestational age (LGA) and intrauterine growth restricted (IUGR) versus appropriate for gestational age (AGA) normal pregnancies and associate them with various perinatal parameters.

METHODS

Plasma irisin and insulin concentrations were measured by enzyme-linked immunosorbent assay (ELISA) and immunoradiometric assay (IRMA), respectively, in a cohort of 80 mothers delivering LGA (n = 30), IUGR (n = 30) and AGA (n = 20) singleton full-term infants.

RESULTS

Maternal irisin concentrations were similar among LGA, IUGR and AGA groups and did not correlate with respective insulin ones or maternal body mass index. In a combined group, maternal irisin concentrations decreased with advancing gestational age (p < 0.001) and were lower in multi-, compared to nulliparous women (p = 0.004). In the IUGR group, maternal irisin concentrations were higher in cases of smoking (p = 0.006).

CONCLUSIONS

Irisin may not be differentially regulated in insulin resistance-associated pregnancy disorders resulting in fetal macrosomia and IUGR. Maternal irisin down-regulation with advancing gestation could possibly contribute to the observed maternal fat accumulation and progressive insulin resistance towards term. Similarly, lower maternal irisin concentrations in multiparous women may reflect the documented positive association between parity and fat deposition. Irisin up-regulation in cases of smoking may indicate the need for enhanced oxygen consumption to maintain energy production under conditions of hypoxia.

Cord blood irisin at the extremes of fetal growth

BACKGROUND/AIMS

Irisin, a novel myokine with antiobesity properties, drives brown-fat-like conversion of white adipose tissue, thus increasing energy expenditure and improving glucose tolerance. We aimed to investigate circulating irisin concentrations in large-for-gestational-age (LGA) and intrauterine-growth-restricted (IUGR) fetuses, both associated with metabolic dysregulation and long-term susceptibility to obesity and metabolic syndrome development.

METHODS

Plasma irisin and insulin concentrations were determined by ELISA and IRMA, respectively, in 80 mixed arteriovenous cord blood samples from LGA (n=30), IUGR (n=30) and appropriate-for-gestational-age (AGA, n=20) singleton full-term pregnancies. Fetuses were classified as LGA, IUGR or AGA, based on customized birth-weight standards adjusted for significant determinants of fetal growth.

RESULTS

Fetal irisin concentrations were lower in IUGR cases than AGA controls (p=0.031). Cord blood irisin concentrations were similar in LGA and AGA groups and positively correlated with birth-weight, as well as customized centiles (r=0.245, p=0.029 and r=0.247, p=0.027, respectively). Insulin concentrations were higher in LGA, compared to AGA fetuses (p=0.036). In the LGA group, fetal irisin concentrations positively correlated with fetal insulin concentrations (r=0.374, p=0.042).

CONCLUSIONS

Impaired skeletal muscle metabolism in IUGR fetuses may account for their irisin deficiency, which may be part of the fetal programming process, leading to increased susceptibility to later metabolic syndrome development. Furthermore, irisin down-regulation may predispose IUGR infants to hypothermia at birth, by inducing less "browning" of their adipose tissue and consequently less non-shivering thermogenesis. Irisin upregulation with increasing birth-weight may contribute to a slower fat gain during early infancy ("catch-down"), by promoting higher total energy expenditure. The positive correlation between irisin and insulin in the LGA group may reflect a counterbalance of the documented hyperinsulinemia, which is partly responsible for the excessive fat deposition in the LGA fetus.

Adropin concentrations in term pregnancies with normal, restricted and increased fetal growth

OBJECTIVE

To determine levels of adropin (implicated in insulin resistance and endothelial dysfunction) in intrauterine growth restricted (IUGR), large (LGA) and appropriate for gestational age (AGA) pregnancies.

METHODS

Cord-blood (UC) adropin and insulin concentrations were measured in 30 IUGR, 30 LGA and 20 AGA full-term infants and their mothers (MS).

RESULTS

No significant differences in adropin concentrations were observed between the three groups. In the IUGR group MS adropin was significantly decreased when neonates had higher birth weights [b = -0.003, 95% CI -0.006 to 0.0, p = 0.043]. In all groups, MS adropin levels were positively correlated with UC ones (r = 0.282, p = 0.011) and were significantly increased in female neonates [b = 0.977, 95% CI 0.122-1.832, p = 0.026]. In the LGA group, MS insulin was negatively correlated with UC adropin (r =  -0.362 p = 0.049).

CONCLUSIONS

Increased maternal adropin levels in severe IUGR cases might represent a regulatory feedback mechanism against endothelial placental dysfunction. The positive correlation between maternal and umbilical cord adropin levels implies its transplacental transfer. Increased maternal adropin levels in female neonates could be attributed to interaction of adropin with fetal estrogens through vascular endothelial growth factor (VEGF). The negative correlation between maternal insulin and fetal adropin levels in the LGA group is probably attributed to their respective insulin resistance.

Urinary leukotriene E4 levels in atopic and non-atopic preschool children with recurrent episodic (viral) wheezing: a potential marker?

Backround: Reliable biological markers for the differentiation of asthma phenotypes in preschool children with wheezing are lacking. The purpose of the study is to assess the relationship of urinary Leukotriene E4 (U-LTE4) to particular asthma phenotypes in preschool children with recurrent episodic (viral) wheezing following upper respiratory tract infections with or without atopic predisposition.

METHODS

Ninety-six preschool patients with recurrent episodic wheezing participated, 52 atopic and 44 non-atopic, during exacerbation and in remission. Exacerbation was defined on clinical basis (wheeze in the presence of coryzal symptoms). Atopy was determined by specific serum IgE measurement and skin-prick testing. U-LTE4 was determined by enzyme immunoassay. Thirty-six age-matched, non-asthmatic, non-atopic children served as controls.

RESULTS

During exacerbation, U-LTE4 was significantly higher in all children with recurrent episodic wheezing in comparison to A: Remission: 642.20 ± 268 versus 399.45 ± 204, p value <0.001 and B:

CONTROLS

642.20 ± 268 versus 271.39 ± 83, p value <0.001. Atopic patients demonstrated significantly higher levels of U-LTE4 compared to non-atopic, both during exacerbation 872.13 ± 246 versus 613.15 ± 150, p value = 0.0013 and during remission 507.59 ± 182 versus 283.59 ± 160, p value <0.001. During remission, a highly significant difference of U-LTE4 was found when controls were compared to atopic patients: 271.39 ± 83 versus 507.59 ± 182, p value = 0.002 but not when compared to non-atopic ones: 271.39 ± 83 versus 283.59 ± 160, p value = 0.432.

CONCLUSION

U-LTE4 is strongly associated with the acute wheeze episode in preschool children, more so in atopics. Increased basal levels of U-LTE4 occur only in atopics. This suggests a potential role of U-LTE4 as a marker of atopic, virus-induced asthma in preschool children.

Biochemical markers of bone resorption are present in human milk: implications for maternal and neonatal bone metabolism

AIM

This study investigated breast milk and maternal serum concentrations of biochemical markers of bone resorption, which may be implicated in both maternal and neonatal bone metabolism.

METHODS

Tests were carried out on 85 parturients 3-4 days after they gave birth. We measured their breast milk and serum concentrations for soluble receptor activator of nuclear factor kappaB ligand (sRANKL) and cross-linked N-telopeptide of type I collagen (NTx). The sRANKL and NTx concentrations were associated with several perinatal parameters.

RESULTS

Soluble receptor activator of nuclear factor kappaB ligand was detectable in breast milk at considerably lower concentrations than in maternal serum (p < 0.001), and these breast milk sRANKL concentrations were decreased in maternal diabetes (b = -0.366, 95% CI -0.622 to -0.110, p = 0.006). Breast milk NTx concentrations were higher in exclusive lactation (b = 0.269, 95% CI 0.014-0.524, p = 0.039), but lower in Caesarean sections (b = -0.224, 95% CI -0.428 to -0.019, p = 0.032).

CONCLUSION

Soluble receptor activator of nuclear factor kappaB ligand is downregulated in breast milk, particularly in the case of diabetes. Breast milk NTx upregulation characterises exclusive lactation, and its downregulation characterises Caesarean section deliveries. Nutritional interventions in foetal life and early infancy may programme adult bone health and ameliorate diseases with developmental origins, such as osteoporosis.

Plant sterols-enriched diet decreases small, dense LDL-cholesterol levels in children with hypercholesterolemia: a prospective study

Background

Small dense low density lipoprotein-cholesterol (sdLDL-C) molecules are more atherogenic compared with large buoyant ones. Phytosterols-enriched diets are effective in decreasing total cholesterol (TC) and low density lipoprotein-cholesterol (LDL-C) concentrations in hyperlipidemic children without significant adverse effects. Limited data on the impact of such a diet on sdLDL-C levels is available in adults while there are no reports concerning children. The purpose of this study is to prospectively evaluate the effect of the daily consumption of 2 g of plant sterols on sdLDL-C levels in children with hypercholesterolemia.

Methods

Fifty-nine children, 25 with LDL-C ≥ 3.4 mmol/l (130 mg/dl) and 34 with LDL-C < 3.4 mmol/l, aged 4.5-15.9 years, were included in the study. A yogurt-drink enriched with 2 g of plant sterols was added to the daily diet of hypercholesterolemic children and 6–12 months later lipid profiles were reassessed. Direct quantitative methods were used to measure LDL-C and sdLDL-C levels.

Results

The consumption of plant sterols reduced sdLDL-C significantly (p < 0.001), but levels remained higher compared with controls (p < 0.001). TC, LDL-C, non high density lipoprotein-cholesterol (NonHDL-C) and apolipoprotein B (ApoB) levels also decreased significantly (p < 0.05). The median reduction of sdLDL-C and LDL-C was 16.6% and 13%, respectively. These variables decreased >10% in sixteen children (64%), independently from baseline levels, sex, age and body mass index (BMI). High density lipoprotein-cholesterol (HDL-C), lipoprotein a [Lp(a)], and triglycerides (TGs) levels remained unaffected.

Conclusions

Plant sterols decrease sdLDL-C significantly and may be beneficial for children with hypercholesterolemia.

Cord blood netrin-1 and -4 concentrations in term pregnancies with normal, restricted and increased fetal growth

OBJECTIVE

To determine levels of the possible angioregulatory molecules netrin-1 and -4, in intrauterine-growth-restricted (IUGR), large for gestational age (LGA) (both groups characterized by altered angiogenic mechanisms) and appropriate-for-gestational-age (AGA) pregnancies.

METHODS

Cord blood (UC) netrin-1 and -4 concentrations were measured in 30 IUGR, 30 LGA and 20 AGA infants and their mothers (MS).

RESULTS

Netrin-1 and -4 concentrations did not differ in all groups. UC netrin-4 increased with gestational age (b = 0.075, 95% CI 0.029-0.121, p = 0.002). In the IUGR group, MS netrin-4 decreased as birth-weight centiles increased [b = -0.058, 95% CI -0.112 to -0.004, p = 0.036]. In the LGA group, MS netrin-1 decreased with advanced gestational age [b = -0.063, 95% CI -0.105 to -0.022, p = 0.004]. In all cases, MS netrin-1 positively correlated with MS netrin-4 (r = 0.299, p = 0.007), while UC netrin-1 negatively correlated with UC netrin-4 (r = -0.239, p = 0.033).

CONCLUSIONS

Increased UC netrin-4 levels with advancing gestational age may reflect its effect on fetal development. Decreased maternal netrin-1 levels in the LGA group possibly represent a negative feedback mechanism against increased angiogenesis. Increased maternal netrin-4 levels in IUGR neonates may reflect in utero hypoxia, while the negative correlations between fetal netrin-1 and -4 levels may exert the dynamic balance between their angio- and anti-angiogenic properties.

Immunoassay-based serum hepcidin reference range measurements in healthy children: differences among age groups

BACKGROUND

Hepcidin is a peptide hormone that plays a key role in regulating iron absorption from the small intestine and body iron distribution. Alterations in hepcidin concentrations have been associated with chronic inflammatory conditions or inherited diseases of iron metabolism. The aim of our study was to evaluate healthy children in order to define normal reference range of serum hepcidin concentrations. The universal use of a reliable commercial ELISA kit gives the ability to compare our results with those from previous studies.

METHODS

We evaluated 180 healthy children (88 boys, mean age: 67.55 ± 39.26 months, median: 60, range: 24-156 months) aged 2-12 years, using an immunoassay kit.

RESULTS

Hepcidin median values were 46.94 ng/ml for boys and 46.79 ng/ml for girls. No significant differences were observed between boys and girls. There seem to be significantly higher values of hepcidin in older children (10-12 years old). This trend was constant and statistically significant in boys after gender and age group stratification. Although this trend was more prominent in girls, it was not statistically significant.

CONCLUSIONS

This study aims at setting up reference values for serum hepcidin concentrations in healthy pediatric population by using a well-established laboratory kit. The difference in hepcidin concentrations in older children could be attributed to different growth rates. Additionally, differences between values in adults and children could reflect alterations in iron metabolism between those two age groups.

The potential role of the lectin pathway of complement in the host defence of full-term intrauterine growth restricted neonates at birth

OBJECTIVE

To prospectively investigate the potential role of the lectin pathway of complement in intrauterine-growth-restriction (IUGR, associated with impaired immunocompetence and increased risk for neonatal infections), by determining cord blood concentrations of mannose-binding lectin (MBL), H-ficolin and L-ficolin (important mediators of neonatal innate immunity) in IUGR and appropriate for gestational age (AGA) pregnancies. Furthermore, we aimed to describe correlations among cord blood MBL, H- and L-ficolin concentrations and with several demographic parameters of the infants at birth.

METHODS

Serum MBL, H- and L-ficolin concentrations were determined by ELISA in 154 mixed arteriovenous cord blood samples from IUGR (n = 50) and AGA (n = 104) singleton full-term infants.

RESULTS

Cord blood MBL concentrations were significantly lower in IUGR cases than AGA controls (p = 0.029). No differences in cord blood H- and L-ficolin concentrations were observed between groups. In the IUGR group, cord blood MBL concentrations negatively correlated with respective L-ficolin ones (r = -0.442, p = 0.001).

CONCLUSIONS

The relatively decreased MBL expression in IUGR fetuses at term could possibly contribute to IUGR-associated neonatal immunodeficiency, predisposing to increased susceptibility to infections. The negative correlation between MBL and L-ficolin concentrations in the IUGR group might suggest an underlying immune variation and needs to be further investigated.

Intrauterine growth restriction may not suppress bone formation at term, as indicated by circulating concentrations of undercarboxylated osteocalcin and Dickkopf-1

The objective was to investigate circulating concentrations of bone formation markers (undercarboxylated osteocalcin [Glu-OC], an established marker of bone formation during fetal and early postnatal life], and Dickkopf-1 [DKK-1], a natural inhibitor of osteoblastogenesis during fetal development]) in intrauterine-growth-restricted (IUGR; associated with impaired fetal skeletal development) and appropriate-for-gestational-age (AGA) pregnancies. Circulating concentrations of Glu-OC and DKK-1 were determined by enzyme immunoassay in 40 mothers and their 20 asymmetric IUGR and 20 AGA singleton full-term fetuses and neonates on postnatal day 1 (N1) and 4 (N4). Parametric tests were applied in the statistical analysis. No significant differences in Glu-OC concentrations were observed between IUGR and AGA groups, whereas fetal DKK-1 concentrations were lower in the IUGR group (P = .028). In both groups, maternal Glu-OC and DKK-1 concentrations were lower than fetal, N1, and N4 concentrations (P ≤ .012 in all cases), whereas fetal Glu-OC concentrations were higher than N1 and N4 ones (P ≤ .037 in all cases). In addition, N1 Glu-OC concentrations were higher than N4 concentrations (P = .047). Finally, maternal Glu-OC and DKK-1 concentrations positively correlated with fetal, N1, and N4 ones (r ≥ 0.404, P ≤ .01 in all cases). Fetal/neonatal bone formation may not be impaired in full-term asymmetric IUGR infants, as indicated by the similar Glu-OC concentrations in both groups. Fetal DDK-1 concentrations are lower in the IUGR group, representing probably a compensatory mechanism, favoring the formation of mineralized bone. Fetal/neonatal bone turnover is markedly enhanced compared with maternal one and seems to be associated with the latter in both late pregnancy and early postpartum.

Omentin-1 and vaspin are present in the fetus and neonate, and perinatal concentrations are similar in normal and growth-restricted pregnancies

The aim of this study was to investigate circulating concentrations of omentin-1 and vaspin (adipocytokines predominantly secreted by visceral adipose tissue and not yet investigated in perinatal life) in maternal, fetal, and neonatal samples from intrauterine growth-restricted (IUGR; associated with altered development of adipose tissue) and appropriate-for-gestational-age (AGA) pregnancies and to correlate them with the respective insulin concentrations. Serum omentin-1 and vaspin concentrations were determined by enzyme immunoassay in 40 mothers and their 20 IUGR and 20 AGA singleton full-term fetuses and neonates on postnatal day 1 (N1) and day 4 (N4). Both hormones were detectable in fetal and neonatal blood (omentin-1 [mean ± SD, in nanograms per milliliter]: AGA vs IUGR group--fetal: 11.32 ± 1.88 vs 10.47 ± 1.30, N1: 10.74 ± 1.42 vs 10.46 ± 1.54, and N4: 10.90 ± 2.72 vs 11.35 ± 3.92; vaspin [median, minimum-maximum; in nanograms per milliliter]: AGA vs IUGR group--fetal: 0.39 [0.04-19.06] vs 0.40 [0.05-1.34], N1: 0.40 [0.04-16.70] vs 0.44 [0.23-3.34], and N4: 0.49 [0.02-8.89] vs 0.55 [0.06-3.92]). No significant differences in omentin-1 or vaspin concentrations were observed between IUGR and AGA groups, whereas fetal and N1 insulin concentrations were lower in the former (P = .025 and P = .027, respectively). In both groups, fetal omentin-1 concentrations were higher (P ≤ .018), whereas vaspin concentrations were lower (P ≤ .001), than maternal ones. Furthermore, maternal vaspin concentrations were higher in cases of cesarean delivery (P = .024). Omentin-1 and vaspin concentrations did not correlate with the respective insulin ones. In conclusion, omentin-1 and vaspin are present in the fetus and neonate. Perinatal concentrations of omentin-1 and vaspin are similar in IUGR cases and AGA controls--despite lower insulin concentrations in the former--and do not correlate with the respective insulin concentrations. Higher omentin-1 concentrations in the fetus may be crucial to enhance a growth-promoting effect, whereas lower maternal vaspin concentrations in cases of vaginal delivery may be attributed to spontaneous term delivery inflammation.

Clara cell protein in full-term pregnancies: the influence of intrauterine growth restriction

BACKGROUND

Clara cell protein (CC16) is an immunomodulatory/anti-inflammatory broncho-alveolar-derived molecule and a biomarker of pulmonary epithelial cells maturity and alveolo-capillary membrane injury. Intrauterine growth-restricted (IUGR) neonates may present with structural lung immaturity, impaired immunocompetence and increased risk for respiratory infections and chronic obstructive lung disease in later life.

OBJECTIVES

To investigate circulating CC16 concentrations in maternal, fetal, and neonatal samples from IUGR and appropriate for gestational age (AGA) pregnancies.

METHODS

Serum CC16 concentrations were determined by EIA in 40 mothers and their 20 IUGR and 20 AGA singleton full-term fetuses-neonates on postnatal days 1 (N1) and 4 (N4).

RESULTS

No significant differences in CC16 concentrations were observed between IUGR and AGA groups. In both groups, maternal CC16 concentrations were lower compared to N1 and N4 ones (P < 0.001 in each case). Fetal CC16 concentrations were significantly lower compared to N1 and N4 ones (P < 0.001 in each case). In the AGA group, N1 CC16 concentrations were significantly higher than N4 ones (P < 0.001). Combining groups, N1 CC16 concentrations positively correlated with gestational age (r = 0.364, P = 0.021). Finally, the effect of gender, parity, and maternal age on CC16 concentrations was not significant.

CONCLUSIONS

The lack of differences in CC16 concentrations between IUGR and AGA groups possibly suggests that the lung immaturity and later respiratory diseases, associated with the former, may not be related to early CC16 deficiency. CC16 concentrations increase with advancing gestational age and peak on the first day of life, possibly indicating a vital role of the protein in fetal lung maturation and extrauterine pulmonary adaptation.

Calprotectin in human cord blood: relation to perinatal parameters and restricted fetal growth

OBJECTIVE

To determine cord blood levels of calprotectin, a protein that is increased in inflammatory states and released by activated neutrophils has apoptosis-inducing activity.

MATERIALS AND METHODS

Cord-blood calprotectin concentrations were determined in intrauterine-growth-restricted (IUGR, usually associated with increased neutrophil activation and apoptosis, n=50) and appropriate-for-gestational-age (AGA, n=110) single full-term pregnancies, and were correlated with perinatal demographic parameters.

RESULTS

No significant differences exists between the IUGR and AGA groups, implying that calprotectin at birth does not reflect increased neutrophil activation and apoptosis expected in IUGR. However, in IUGRs, calprotectin concentrations increased with every gestational week [b=45.3, 95% confidence interval (CI): 13.5-77.1, P=0.006], suggesting concomitant up-regulation of neutrophil activation and apoptosis. A combined group showed significantly decreased calprotectin concentrations in cesarean sections [b=-74.5, 95% CI: -115.2-(-33.9), P<0.001], pointing to excessive inflammatory response in vaginal deliveries. Finally, birth weight, customized centile, gender, maternal age and parity do not impact on cord blood calprotectin concentrations.

CONCLUSIONS

Cord blood calprotectin concentrations at term are independent of intrauterine growth, gender, parity and maternal age and probably do not reflect the increased neutrophil activation and excessive apoptosis expected in IUGR.

Serum Beta-2-microglobulin levels in intrauterine growth-restricted and normal pregnancies

OBJECTIVE

It was the aim of this study to investigate circulating levels of beta(2)-microglobulin (a marker of renal function) in mothers and fetuses/neonates from intrauterine growth-restricted (IUGR, characterized by impaired nephrogenesis) and appropriate for gestational age (AGA) pregnancies.

METHODS

Serum beta(2)-microglobulin levels were determined in 40 parturients and their 20 IUGR and 20 AGA fetuses/neonates on postnatal days 1 (N1) and 4 (N4). Comparatively, creatinine concentrations were measured.

RESULTS

No significant differences in beta(2)-microglobulin levels were observed between the 2 groups. In both groups, maternal serum beta(2)-microglobulin levels were significantly lower than fetal, N1 and N4 levels (in all cases p < 0.001 in the AGA group and p <or= 0.002 in the IUGR group). In the AGA and IUGR groups, N4 beta(2)-microglobulin levels were significantly elevated compared with fetal (p = 0.004 and p = 0.001, respectively) and N1 levels (p = 0.002 and p = 0.001, respectively). In both groups, maternal and fetal beta(2)-microglobulin levels did not correlate, but beta(2)-microglobulin and creatinine levels positively correlated in maternal and neonatal samples (in all cases r >or= 0.342 and p <or= 0.031).

CONCLUSIONS

Serum beta(2)-microglobulin levels do not differ between IUGR and AGA groups, significantly increase after birth and are not associated with gender or gestational age. Furthermore, maternal levels do not correlate with fetal levels, implying the presence of a placental barrier.

Perinatal changes of plasma resistin concentrations in pregnancies with normal and restricted fetal growth

BACKGROUND

The adipocytokine resistin inhibits adipogenesis and induces insulin resistance. Intrauterine growth-restricted (IUGR) neonates have reduced fat mass and changes of endocrine/metabolic mechanisms, predisposing to insulin resistance and metabolic syndrome in adult life.

OBJECTIVES

To investigate plasma resistin concentrations in maternal, fetal and neonatal samples from IUGR and appropriate-for-gestational-age (AGA) pregnancies and correlate them with respective insulin concentrations.

METHODS

Plasma resistin and insulin concentrations were determined in 40 mothers and their 20 IUGR and 20 AGA singleton full-term fetuses and neonates on postnatal day 1 (N1) and day 4 (N4).

RESULTS

No significant differences in resistin concentrations were observed between AGA and IUGR groups. In the AGA group, maternal resistin concentrations were significantly lower compared to fetal, N1 and N4 ones (p = 0.003, p = 0.017 and p = 0.039, respectively). Maternal resistin concentrations positively correlated with fetal ones (r = 0.527, p = 0.02). In the IUGR group, maternal resistin concentrations were significantly lower compared to N1 (p < 0.001) and positively correlated with N4 concentrations (r = 0.626, p = 0.007). In both groups, the effect of gender, mode of delivery, parity and adjusted birth weight (customized centiles) on resistin concentrations was not significant. No correlation between resistin and insulin concentrations was documented.

CONCLUSIONS

Lack of difference in resistin concentrations between IUGR and AGA groups, and lack of correlation between resistin and insulin concentrations as well as customized centiles, possibly suggests that resistin may not be directly involved in the regulation of insulin sensitivity and adipogenesis in the perinatal period. Mode of delivery and parity are not associated with circulating resistin concentrations.

Insulin-like growth factor (IGF)-I and insulin in normal and growth-restricted mother/infant pairs

Insulin-like growth factor (IGF)-I and insulin are essential for fetal growth. We investigated perinatal changes of both factors in 40 mothers and their 20 appropriate-for-gestational-age (AGA) and 20 intrauterine-growth-restricted (IUGR) fetuses and neonates on day 1 (N1) and day 4 (N4) postpartum. Fetal and N1, but not N4, IGF-I levels were increased in AGA (P < .001 and P = .037, resp.). N1 insulin levels were lower in IUGR (P = .048). Maternal, fetal, and N1 IGF-I, and fetal insulin levels positively correlated with customized centiles (r = .374, P = .035, r = .608, P < .001, r = .485, P = .006, and r = .654, P = .021, resp.). Female infants presented elevated fetal and N4 IGF-I levels (P = .023 and P = .016, resp.). Positive correlations of maternal, fetal, and neonatal IGF-I levels, and fetal insulin levels with customized centiles underline implication of both hormones in fetal growth. IUGR infants present gradually increasing IGF-I levels. Higher IGF-I levels are documented in females.