ACTH and cortisol cord plasma concentrations in preterm and term infants

Prophylactic early low-dose hydrocortisone and survival without bronchopulmonary dysplasia among extremely preterm infants born at 22-27 weeks' gestation

OBJECTIVE

To compare survival without BPD among extremely preterm infants (EPI) who received prophylactic early low-dose hydrocortisone (PEH) with those who did not (non-PEH).

STUDY DESIGN

This single-center retrospective study compared risk-adjusted rates of survival without BPD, BPD, bowel perforation, and late-onset sepsis among infants (22-27 weeks' gestation at birth) who received PEH (n = 82) and who did not (n = 205).

RESULTS

Infants in the PEH group were of lower gestational age, lower birthweight, and higher day-1 risk of death/BPD. After adjusting for risk of death/BPD, PEH-treated infants demonstrated increased survival without BPD (aOR 2.04, 95%CI 1.1-3.7), and lower BPD rates (aOR 0.46, 95%CI 0.25-0.87). Importantly, bowel perforation or sepsis rate were similar among both groups.

CONCLUSION

After risk adjustment, PEH-treated infants demonstrated improved survival without BPD and did not increase rates of bowel perforation or sepsis. In our cohort of infants, PEH was safe and effective among the sickest preterm neonates.

Hormonal Determinants of Growth and Weight Gain in the Human Fetus and Preterm Infant

The factors controlling linear growth and weight gain in the human fetus and newborn infant are poorly understood. We review here the changes in linear growth, weight gain, lean body mass, and fat mass during mid- and late gestation and the early postnatal period in the context of changes in the secretion and action of maternal, placental, fetal, and neonatal hormones, growth factors, and adipocytokines. We assess the effects of hormonal determinants on placental nutrient delivery and the impact of preterm delivery on hormone expression and postnatal growth and metabolic function. We then discuss the effects of various maternal disorders and nutritional and pharmacologic interventions on fetal and perinatal hormone and growth factor production, growth, and fat deposition and consider important unresolved questions in the field.

Comparison of Homeostasis Model Assessment-Insulin Resistance (HOMA-IR) and the Level of Cortisol Between Preterm and Term Newborns

Introduction According to the thrifty (Barker's) phenotype hypothesis, poor nutrition in fetal and early infancy plays a role in the development and function of the beta cells of the islets of Langerhans, which leads to the development of type 2 diabetes mellitus. Insulin resistance is due to decreased suppressive effect of insulin on hepatic glucose production. Thus, elevated insulin levels during perinatal life may predispose the infant to the development of diabetes mellitus in future life. Intrauterine undernutrition plays an important role in causing adult insulin resistance and diabetes but the exact cause is still unknown. Preterm infants born small for gestational age (SGA) show lower adrenocortical response to stimulation due to an immature hypothalamic-pituitary axis. Methods The cross-sectional study conducted at Rajendra Institute of Medical Sciences, Ranchi from June 2020 to November 2021 included 216 newborns enrolled as per the inclusion and exclusion criteria. Maternal and neonatal details were collected at birth and recorded. Cord blood samples for measurement of serum insulin, glucose, and cortisol were collected from 84 preterm and 132 term neonates. Using this information, homeostasis model assessment-insulin resistance (HOMA-IR) was calculated using a mathematical formula. Insulin resistance was defined as HOMA-IR > 2.5. Based on birth weight and gestational age, they were further categorized into SGA, appropriate for gestational age (AGA), and large for gestational age (LGA). The parametric data were presented as means ± standard deviation (SD), and nonparametric data as medians (first quartile and third quartile). The Student's (independent samples) t-test and Mann-Whitney U test were used to compare mean differences between the two groups for parametric and nonparametric data, respectively. The Spearman correlation coefficient was used to determine the significant association between variables. Results Umbilical cord plasma glucose and serum insulin were high in preterm in comparison to term newborns. Serum cortisol levels were high in term than in preterm newborns. HOMA-IR showed a very strong positive correlation with serum insulin and a moderate positive correlation with serum glucose. HOMA-IR showed a strong negative correlation with gestational age and a moderate negative correlation with birth weight. Insulin resistance was seen in 34 preterm newborns and two term newborns. Insulin resistance was seen in 29.8% (n = 25) of SGA preterm babies, 7.1% (n = 6) of AGA preterm babies, and 1.5% (n = 2) of AGA term newborns. A total of 55.6% of newborns were below normal weight (48.1% had low birth weight, 4.6% had very low birth weight, and 2.8% had extremely low birth weight). Conclusion Our study suggests that preterm newborns are more insulin resistant at birth than term newborns. SGA preterm babies are having a higher incidence of insulin resistance compared to AGA preterm babies. It is clear that high insulin level is needed to overcome high insulin resistance in the very early gestational period. Serum cortisol increases as gestational age and birth weight increase. Thus, serum cortisol helps in the maturation of the fetus and neonatal adaptation at birth.

Association between Low Cord Serum Cortisol Level and Transient Tachypnea of the Newborn in Late Preterm and Term Neonates Delivered by Elective Cesarean Section

OBJECTIVE

Transient tachypnea of the newborn (TTN), a common neonatal respiratory morbidity, is associated with failure of adequate clearance of fetal lung fluid. Glucocorticoids have an important role in lung maturity and the mechanisms of lung fluid clearance. The aim of this study is to assess the association between umbilical cord cortisol levels and transient TTN in late preterm and term neonates delivered by elective cesarean section (CS).

STUDY DESIGN

A case-control study of 37 newborns diagnosed with TTN (cases) was compared with 40 healthy newborns (controls). All infants were delivered by elective CS without labor. Umbilical cord cortisol levels were measured using enzyme-linked immunosorbent assay.

RESULTS

Mean cord cortisol levels were significantly lower in cases than controls (131.36 vs. 233.32 nmol/L, p = 0.0001; odds ratio [OR] = 3.7; 95% confidence interval [CI]: 1.40-9.53), respectively. Cord serum cortisol correlated inversely with the duration of tachypnea and the respiratory rate (r =  - 0.678 and -0.535, respectively).

CONCLUSION

Umbilical cord cortisol levels are significantly lower in newborns with transient TTN, and lower cortisol levels are associated with an increased respiratory rate and longer duration of admission. Antenatal glucocorticoids can be recommended for late preterm delivered by CS.

KEY POINTS

· Umbilical cord cortisol levels were lower in late preterm infants with TTN.. · Late preterm newborn with severe TTN and NICU hospitalization have lower cord cortisol levels.. · Antenatal glucocorticoids can be recommended for late preterm delivered by CS..

Androgens Tend to Be Higher, but What about Altered Progesterone Metabolites in Boys and Girls with Autism?

Background: Evidence exists that steroid hormones are altered in individuals with autism, especially androgens. Despite lower prevalence in girls than boys, evidence of potential alterations in progesterone metabolites is sparse, so the aim of this study was to elucidate different progesterone metabolites in affected children with autism versus healthy controls. Material and Methods: Circadian urine samples from 48 boys and 16 girls with autism spectrum disorders and a matched case−control group were analysed for progesterone metabolites by gas chromatography−mass spectrometry and normalised for creatinine excretion. Results: In boys with autism, the majority of progesterone metabolites were reduced, such as progesterone, 6a-OH-3a5b-TH-progesterone, or 20a-DH-progesterone (p < 0.01 for all). In girls with autism, a similar pattern of reduction in progesterone metabolites was detected; however, potentially due to the relatively small sample, this pattern was only detectable on the level of a trend. Discussion: As stated, androgen levels are higher in boys and girls with autism, but evidence for progesterone metabolites is much sparser. The pattern of a decrease in progesterone metabolites suggests the existence of an altered routing of steroid metabolites, probably in combination with a dysregulation of the HPAG axis. As, recently, increased CYP17A1 activity has been suggested, the stronger routing towards androgens is further implied in line with our findings of lower progesterone concentrations in boys and girls with autism than healthy controls.

Adrenocortical Dysfunctions in Neonatal Septic Shock

The prevalence of adrenal insufficiency at the onset of neonatal septic shock was estimated. Total serum cortisol and adrenocorticotropin (ACTH) levels were measured at the onset of septic shock in term and preterm neonates. Serum cortisol levels were measured again after 30 min of 1 µg adrenocorticotropin injection. The authors defined Adrenocortical insufficiency as absolute adrenalin sufficiency (baseline serum cortisol < 15 µg/dL, rise in serum cortisol < 9 µg/dL after ACTH injection), or relative adrenal insufficiency (baseline cortisol ≥ 15 µg/dL, rise < 9 µg/dL). Thirty neonates with septic shock were enrolled. Six of them had absolute adrenal insufficiency while 2 neonates had relative adrenal insufficiency. Thus, the prevalence of adrenal insufficiency was 27% at the onset of neonatal septic shock, 95% confidence interval: 12%-46%. Seventeen (57%) neonates with septic shock had cortisol levels (< 15 µg/dL) with adequate rise (≥ 9 µg/dL) after ACTH stimulation indicating depressed baseline levels, which responded to ACTH stimulation.

Association between Baseline Cortisol Serum Concentrations and the Effect of Prophylactic Hydrocortisone in Extremely Preterm Infants

OBJECTIVE

To define nomograms of serum cortisol values before 24 hours of postnatal life for extremely preterm infants and determine whether baseline cortisol values affect the benefit/risk ratio of prophylactic hydrocortisone to improve survival without bronchopulmonary dysplasia (BPD).

STUDY DESIGN

We performed a predefined secondary analysis of the multicenter randomized controlled PREMILOC trial that included inborn infants delivered before 28 weeks of gestation. Nomograms of baseline serum cortisol values measured in 325 enrolled patients were determined for male and female neonates and correlated to perinatal events. BPD-free survival and severe adverse events were analyzed in placebo and hydrocortisone groups according to the cortisol z score in multivariate logistic regression models.

RESULTS

Increased cortisol levels measured before 24 hours following birth were associated with a significantly higher chance of BPD-free survival only in placebo-treated infants (aOR [95% CI] 1.57 [1.08-2.27], P = .02) based on sex-specific nomograms for baseline cortisol levels. The cortisol z score for infants treated with prophylactic hydrocortisone predicted a risk of high-grade intraventricular hemorrhage (aOR [95% CI] 1.82 [1.06-3.15], P = .03) and spontaneous intestinal perforation (aOR [95% CI] 4.81 [1.34-17.22], P = .02).

CONCLUSIONS

We found no predictive value of baseline cortisol levels for BPD-free survival in infants born extremely preterm treated with hydrocortisone. However, high cortisol levels early after birth were associated with a greater risk of severe intraventricular hemorrhage and spontaneous intestinal perforation in infants treated with hydrocortisone and, therefore, a lower benefit/risk ratio for the treatment.

TRIAL REGISTRATION

EudraCT 2007-002041-20, ClinicalTrial.gov: NCT00623740.

Inferior Adrenal Artery PI in Fetuses with IUGR: Value Indicating Early Blood Redistribution and Steroidogenic Response

OBJECTIVE

To characterize the inferior adrenal artery (IAA) pulsatility index (PI) in intrauterine growth-restricted (IUGR) fetuses without brain sparing.

METHODS

Twenty-three IUGR fetuses with a normal Doppler cerebroplacental ratio (CPR) and 23 normal controls were included in this prospective cross-sectional study. The PI of the IAA was recorded using routine transabdominal Doppler ultrasound. The differences in Doppler characteristics, perinatal outcomes, and steroidogenesis in the umbilical vein at birth (adrenocorticotropic hormone [ACTH] and cortisol [F] levels) were compared between the 2 groups. The correlations between IAA-PI and steroidogenesis were assessed in the IUGR group.

RESULTS

IAA-PI was significantly lower in IUGR fetuses than in normal controls (0.85 vs 1.18 at first scan, 0.78 vs 0.92 at last scan; both P < 0.001). The plasma F and ACTH levels in IUGR cases were significantly higher than those of the normal controls (18.2 vs 12.4 µg/dL and 280.5 vs 125.6 pg/mL for F and ACTH, respectively; both P < 0.001). There were negative correlations between IAA-PI and plasma F values and between IAA-PI and ACTH values in the IUGR group (r = -0.774 and -0.82 at first scan, r = -0.525 and -0.45 at last scan, respectively; P < 0.001).

CONCLUSION

Increased adrenal gland blood flow with concomitant increases in ACTH and F levels were observed in IUGR fetuses. IAA-PI is useful to assess early blood redistribution and may be beneficial for evaluating the steroidogenic response in high-risk pregnancies.

Prenatal greenspace exposure and cord blood cortisol levels: A cross-sectional study in a middle-income country

Exposure to greenspace has been associated with reduced stress; however, the available evidence on such an association for the fetus is still very scarce. We, for the first time, investigated the association between maternal greenspace exposure and the level of cortisol, a stress hormone, in the cord blood. Our study was based on a cohort of 150 pregnant women in Sabzevar, Iran (2018). We comprehensively assessed greenspace exposure for each participant through (i) residential surrounding greenspace (using two satellite-derived vegetation indices), (ii) residential proximity to green spaces, (iii) maternal visual access to greenspace, (iv) use of public and private green spaces, (v) having a private garden, and (vi) the number of plant pots at home. Linear regression models were developed to assess the association of each indicator of greenspace exposure with cord blood cortisol levels, controlled for the relevant covariates. We observed that a higher residential surrounding greenspace (100 m buffer), having a window with greenspace view, window greenspace coverage of more than 50%, frequently looking at greenspace through window, residential proximity to large green spaces, and more time spent in green spaces were associated with lower cortisol levels in the cord blood. The findings for residential surrounding greenspace at 300 m and 500 m buffers, residential proximity to any green space regardless of its size, having a private garden, and number of plant pots at home were not conclusive. While about one-third of the association between residential surrounding greenspace (100 m buffer) could be mediated through reduction in exposure to air pollution, we did not observe any strong evidence for such a mediatory role for the visual access to greenspace. The findings stratified for parental education and housing type showed mixed patterns. Our findings suggest that more greenspace exposure might reduce cortisol level in the cord blood.

Phenotypes of Bronchopulmonary Dysplasia

Bronchopulmonary dysplasia (BPD) is the most common chronic morbidity in preterm infants. In the absence of effective interventions, BPD is currently a major therapeutic challenge. Several risk factors are known for this multifactorial disease that results in disrupted lung development. Inflammation plays an important role and leads to persistent airway and pulmonary vascular disease. Since corticosteroids are potent anti-inflammatory agents, postnatal corticosteroids have been used widely for BPD prevention and treatment. However, the clinical responses vary to a great degree across individuals, and steroid-related complications remain major concerns. Emerging studies on the molecular mechanism of lung alveolarization during inflammatory stress will elucidate the complicated pathway and help discover novel therapeutic targets. Moreover, with the advances in metabolomics, there are new opportunities to identify biomarkers for early diagnosis and prognosis prediction of BPD. Pharmacometabolomics is another novel field aiming to identify the metabolomic changes before and after a specific drug treatment. Through this "metabolic signature," a more precise treatment may be developed, thereby avoiding unnecessary drug exposure in non-responders. In the future, more clinical, genetic, and translational studies would be required to improve the classification of BPD phenotypes and achieve individualized care to enhance the respiratory outcomes in preterm infants.

Plasma cortisol and ACTH levels in 416 VLBW preterm infants during the first month of life: distribution in the AGA/SGA population

OBJECTIVE

The aim of this study is to establish the serum level distribution of cortisol and ACTH in VLBW preterm newborns and determine which neonates are ideal candidates for the stimulation test for adrenal insufficiency.

METHODS

Plasma cortisol and ACTH levels were evaluated in 416 VLBW newborns on days 1, 7, and 30 of life. Gender, gestational age, weight, type of delivery, RDS prophylaxis, and perinatal morbidities were considered as potential variability factors.

RESULTS

Cortisol and ACTH levels significantly decreased between 1, 7, and 30 days. Significantly higher cortisol levels were found at lower gestational ages and in infants born by vaginal delivery, whereas lower levels were observed in those born after maternal corticosteroid treatment. The distribution of cortisol and ACTH levels in healthy infants born by cesarian section is presented.

CONCLUSION

Even if high or low levels were not frequently linked to illness, the presented distribution data may indicate that the newborns are ideal candidates for the stimulation test.

Prophylactic postnatal corticosteroids: Early hydrocortisone

Inflammation is a key contributor to the pathogenesis of bronchopulmonary dysplasia (BPD) in preterm infants, and cortisol plays a central role in controlling inflammation. Insufficient cortisol limits the ability of the sick newborn to handle stress and inhibit pulmonary inflammation. Evidence of lower cortisol and lower response to adrenocorticotropic hormone in infants subsequently developing BPD led to studies of early low-dose hydrocortisone to prevent BPD. Based on four randomised clinical trials enrolling almost 1000 extremely preterm infants, prophylaxis of early adrenal insufficiency with low-dose hydrocortisone significantly decreased BPD and mortality, as well as medical treatment for a patent ductus arteriosus. An increase in late-onset sepsis reported in the most immature infants had no adverse effect on mortality or neurodevelopmental outcomes. There was no increase in gastrointestinal perforation in the absence of indomethacin. The demonstrated beneficial effects of early low-dose hydrocortisone make a strong case for its use in extremely preterm infants at high risk for BPD.

Clinical utility of stimulation tests in infants with suspected adrenal insufficiency (AI)

Diagnosis of adrenal insufficiency (AI) in infants can be difficult. While a low random cortisol can signal AI, often confirmatory tests are required when clinical suspicion is strong but the cortisol levels are equivocal. Several studies have demonstrated that in sick preterm infants, there is relative adrenal insufficiency (RAI) defined as an inadequate cortisol production relative to the degree of stress or illness, a condition which can last for several weeks, while in term infants the adrenal axis is mature at birth (Bagnoli F, Mori A, Fommei C, Coriolani G, Badii S, et al. ACTH and cortisol cord plasma concentrations in preterm and term infants. J Perinatol 2013;33:520-4). Adrenocorticotrophic hormone (ACTH) and corticotrophin releasing hormone (CRH) stimulation tests have been validated in infants in several studies. In light of recent reports of false-negative results of stimulation tests, it is imperative to highlight the pitfalls of these tests. The purpose of this communication is to bring attention to the accuracy of timing of these tests in infants.

Steroid Metabolites Support Evidence of Autism as a Spectrum

Objectives: It is common nowadays to refer to autism as a spectrum. Increased evidence of the involvement of steroid metabolites has been shown by the presence of stronger alterations in Kanner's syndrome compared with Asperger syndrome. Methods: 24 h urine samples were collected from 20 boys with Asperger syndrome, 21 boys with Kanner's syndrome, and identically sized control groups, each matched for age, weight, and height for comprehensive steroid hormone metabolite analysis via gas chromatography-mass spectrometry. Results: Higher levels of most steroid metabolites were detected in boys with Kanner's syndrome and Asperger syndrome compared to their matched controls. These differences were more pronounced in affected individuals with Kanner's syndrome versus Asperger syndrome. Furthermore, a specific and unique pattern of alteration of androsterone, etiocholanolone, progesterone, tetrahydrocortisone, and tetrahydrocortisol was identified in boys with Kanner's syndrome and Asperger syndrome. Interestingly, in both matched samples, only androsterone, etiocholanolone, progesterone, tetrahydrocortisone, tetrahydrocortisol, and 5a-tetrahydrocortisol groups were positively correlated. In the Asperger syndrome group, all metabolites showed a positive correlation. In the Kanner's syndrome group, 5-a tetrahydrocortisol with androsterone showed a positive correlation. Conclusions: Due to differences in the level of alteration, the premise that Asperger syndrome is on the mild side of the autism spectrum and that Kanner's syndrome is on the severe side is supported, but alteration patterns yield different phenotypic expressions.

Placental 11β-HSD2 and Cardiometabolic Health Indicators in Infancy

OBJECTIVE

Fetal excessive exposure to glucocorticoids may program cardiometabolic risk. Placental 11 β-hydroxysteroid dehydrogenase 2 (11β-HSD2) serves as a barrier to prevent fetal overexposure to maternal glucocorticoids. It has not been explored whether placental 11β-HSD2 levels are associated with cardiometabolic health in postnatal life.

RESEARCH DESIGN AND METHODS

In a prospective birth cohort study of 246 mother-infant pairs, we measured placental 11β-HSD2 expression and maternal (32-35 weeks of gestation) and cord plasma cortisol concentrations. The primary outcomes were HOMA of insulin resistance (IR) and blood pressure (BP) in infants at age 1 year. Other outcomes included fasting insulin, HOMA β-cell function, carotid intima-media thickness, weight z score, and skinfold thickness (triceps and subscapular) at age 1 year.

RESULTS

Placental 11β-HSD2 expression was negatively correlated with HOMA-IR (r = -0.17, P = 0.021) and fasting insulin (r = -0.18, P = 0.017) and marginally negatively correlated with systolic BP (r = -0.16, P = 0.057) but was not correlated with HOMA of β-cell function, diastolic BP, carotid intima-media thickness, and skinfold thickness (all P > 0.1) in infants at age 1 year. Cord plasma cortisol was negatively correlated to skinfold thickness (r = -0.20, P = 0007) but was not correlated with other outcomes at age 1 year. Maternal plasma cortisol was positively correlated with maximal carotid intima-media thickness (r = 0.20, P = 0.03) but was not correlated with other outcomes. Adjusting for maternal and infant characteristics, the associations were similar.

CONCLUSIONS

The study is the first to show that higher placental 11β-HSD2 expression is associated with lower IR in infancy. Independent cohort studies are required to confirm this novel finding.

Adrenal function of extremely premature infants in the first 5 days after birth

Background There is limited data on adrenal function in the early days after birth in extremely premature infants. The relationship between plasma adrenocorticotrophic (ACTH) and cortisol hormone is central to the integrity of the hypothalamic-pituitary-adrenal (HPA) axis yet there are no studies examining this relationship in prematurity. Methods The aim of this study was to examine the relationship between early morning plasma cortisol and ACTH concentrations during the first 5 days after birth in infants born at less than 28 weeks' gestation and to identify any independent factors that determine plasma cortisol levels in these infants during extreme prematurity. We prospectively studied early morning plasma ACTH and cortisol concentrations in infants born below 28 weeks' gestation during the first 5 days of birth. Plasma cortisol was measured without extraction, using DPC Immulite® 2000 using a solid phase 2 site chemiluminescent immunometric assay. ACTH was measured using a radioimmunoassay. Spearman's correlation was used to examine the relationship between cortisol and ACTH. Multiple regression analysis was used to examine the relationship between plasma cortisol and clinical risk index for babies (CRIB) score, antenatal dexamethasone, mode of delivery and gestation. Results There were 95 infants (53 males) of mean gestation 25.3 ± 1.3 standard deviation (SD) (range 23-27 + 6) weeks. The mean birth weight was 809 ± 17.0 g. The mean plasma cortisol was 400.5 ± 42.6 nmol/L and the mean plasma ACTH was 4.5 ± 0.9 pmol/L. Early morning plasma cortisol correlated significantly with gestation (R = 0.4, p = 0.005). Early morning plasma ACTH did not correlate with early morning plasma cortisol (R = -0.12, p = 0.7). Multiple regression analysis showed that gestation was the only independent determinant of early morning plasma cortisol concentration (beta coefficient = -0.4, p = 0.04). Conclusions The relationship between early morning plasma ACTH and plasma cortisol is either not established or is impaired in infants of less than 28 weeks' gestation in the first 5 days after birth. The plasma cortisol level is mainly determined by gestation and is not directly related to illness severity, antenatal steroids or plasma ACTH in these infants in the first 5 days after birth.

Maternal Blood Pressure, Cord Glucocorticoids, and Child Neurodevelopment at 2 Years of Age: A Birth Cohort Study

BACKGROUND

Pregnancy hypertensive disorders have impaired neurodevelopment in offspring. We aimed to explore the association of normal range maternal blood pressure (BP) with child neurodevelopment, as well as the possible role of placental 11-beta-hydroxysteroid dehydrogenase type 2 (11β-HSD2) therein.

METHODS

Among 1,008 mother-child pairs recruited in Wuhan, China, in 2013-2015, we measured maternal third-trimester BP (systolic BP (SBP) and diastolic BP (DBP)) and cord glucocorticoids (cortisol and cortisone), a marker reflecting placental 11β-HSD2 activity. We evaluated child neurodevelopment using the Bayley Scales of Infant Development (BSID) with obtaining the Mental and Psychomotor Development Index (MDI and PDI). Multiple regression and mediation analysis were performed to estimate the effect.

RESULTS

Each 5 mm Hg increase in maternal third-trimester SBP was associated with 1.54 points decrease in MDI (95% confidence interval (CI) = -2.60, -0.48) and 1.23 points decrease in PDI (95% CI = -2.14, -0.31); similar association was observed between DBP and BSID (adjusted β = -1.32; 95% CI = -2.53, -0.10 for MDI and -1.37; 95% CI = -2.42, -0.33 for PDI). Also, we found significant associations between cord cortisol/cortisone ratio and PDI (adjusted β = 2.95; 95% CI = 0.91, 4.99), as well as between maternal BP and cord cortisol/cortisone ratio (adjusted β = -0.03; 95% CI = -0.06, -0.01 for both SBP and DBP). Mediation analysis revealed that cord cortisol/cortisone ratio explained 6.29% of the association between SBP and PDI, and 6.85% between DBP and PDI.

CONCLUSIONS

Increased maternal normal range BP may affect child neurodevelopment. Furthermore, placental 11β-HSD2 activity might be involved in the process.

Comparative profiling of adrenal steroids in maternal and umbilical cord blood

Fetal steroidome in late pregnancy receives multiple contributions from both maternal and fetal adrenals as well as from placenta. Depressed glucocorticoid levels have been reported in fetal blood at birth, yet studies on mineralocorticoid pathways are sparse. To investigate biosynthesis pathways at birth, adrenal steroids profiles were established in paired mothers and neonates. Forty-six paired healthy term newborns and their mothers from the Aldo cohort were assessed. Steroidomic profiles of mineralocorticoids, glucocorticoids and adrenal androgens were established from umbilical cord and maternal blood at birth using a highly sensitive and specific LC-MS/MS methodology. As compared to maternal blood, umbilical cord blood exhibited high levels of steroids precursors (progesterone and 11-deoxycorticosterone) contrasting with a collapse in corticosterone levels. Consecutively, 18-hydroxycorticosterone and aldosterone levels were also depressed in neonates. Similarly, umbilical cord blood levels of both 17-hydroxyprogesterone and 11-deoxycortisol were higher while cortisol levels sharply decreased. The product-to-substrate ratios evaluating the 11-hydroxylation step (corticosterone/11-deoxycorticosterone and cortisol/11-deoxycortisol) fell for both pathways. As expected, cortisone and 11-dehydrocorticosterone levels exceed those of cortisol and corticosterone in umbilical cord blood reflecting the strong placental 11-β-hydroxysteroid-dehydrogenase type 2 (11βHSD2) activity. Dehydroepiandrosterone-sulphate levels are higher in neonates, while both androstenedione and testosterone levels sharply fell. No significant difference in steroid levels could be observed according the gender except higher testosterone concentrations in umbilical cord of boys. Moreover, a strong and negative relationship between testosterone and progesterone levels was recorded in umbilical cord of boys. These adrenal steroidomic profiling demonstrate a deficit in mineralocorticoids (aldosterone, 18-hydroxycorticosterone and corticosterone) and glucocorticoids (cortisol) in term neonates, reflecting either a relative defect in 11-hydroxylase activity or more likely the strong placental 11-β-HSD2 activity. Collectively, these findings should be taken into account for a better understanding of regulatory interactions between placenta and fetal adrenal.

Paradoxical diurnal cortisol changes in neonates suggesting preservation of foetal adrenal rhythms

Studies suggested the presence of foetal adrenal rhythms of cortisol, which are entrained in antiphase to maternal rhythms. In contrast, neonates are thought to have no adrenal rhythm until 2-3 months after birth. To test the hypothesis that a foetal-type adrenal rhythm is preserved after birth, saliva samples were collected from 65 preterm/term infants during hospital stay (30-40 weeks corrected age) at 10:00 and 19:00 h. Cortisol levels were assessed for their diurnal difference and dependence on antenatal/postnatal clinical variables. Cortisol levels were lower during periods 15-28 days and >28 days than ≤5 days of life. Lower cortisol was associated with pregnancy-induced hypertension (PIH), gestational age <28 weeks, and mechanical ventilation after birth. Higher cortisol was associated with vaginal delivery and non-invasive ventilation support at saliva collection. PIH and non-invasive mechanical ventilation at saliva collection were associated with cortisol levels even after adjustment for postnatal age. Cortisol levels were higher in the evening than in the morning, which was unassociated with gestational and postnatal age. Higher cortisol levels in the evening suggest the preservation of a foetal-type diurnal rhythm. Cortisol levels are associated with intrinsic and extrinsic variables, such as PIH, delivery mode, gestational age, and respiratory conditions.

Temporal and spatial distribution of mast cells and steroidogenic enzymes in the human fetal adrenal

Mast cells are present in the human adult adrenal with a potential role in the regulation of aldosterone secretion in both normal cortex and adrenocortical adenomas. We have investigated the human developing adrenal gland for the presence of mast cells in parallel with steroidogenic enzymes profile and serotonin signaling pathway. RT-QPCR and immunohistochemical studies were performed on adrenals at 16-41 weeks of gestation (WG). Tryptase-immunopositive mast cells were found from 18 WG in the adrenal subcapsular layer, close to 3βHSD- and CYP11B2-immunoreactive cells, firstly detected at 18 and 24 WG, respectively. Tryptophan hydroxylase and serotonin receptor type 4 expression increased at 30 WG before the CYP11B2 expression surge. In addition, HDL and LDL cholesterol receptors were expressed in the subcapsular zone from 24 WG. Altogether, our findings suggest the implication of mast cells and serotonin in the establishment of the mineralocorticoid synthesizing pathway during fetal adrenal development.

Indices of Glucose Homeostasis in Cord Blood in Term and Preterm Newborns

OBJECTIVE

According to the thrifty phenotype hypothesis, intrauterine malnutrition has a role in the etiology of type 2 diabetes. This study was planned to determine the early alterations in indices of glucose homeostasis (glucose, insulin, and cortisol) in term and preterm newborns and the correlations of glucose, insulin, and cortisol levels with insulin resistance indices.

METHODS

A descriptive study comprising 35 term and 35 preterm newborns was carried out from December 2013 to June 2015. Venous cord blood was collected and plasma glucose was analyzed by the glucose oxidase-peroxidase method in an auto analyzer. Serum insulin and cortisol levels were assessed by the enzyme-linked immunosorbent assay. Homeostasis model assessment of insulin resistance (HOMA-IR), quantitative insulin sensitivity check index and glucose insulin ratio were calculated to assess insulin resistance. The data on physical and metabolic parameters were analyzed using standard tests for statistical significance.

RESULTS

In term newborns, mean glucose and cortisol levels (83.6±17.4 mg/dL and 11.88±5.78 µg/dL, respectively) were significantly higher than those in preterm infants (70.4±15.8 mg/dL and 8.9±4.6 µg/dL, respectively). Insulin and HOMA-IR levels were found higher in preterm newborns (10.8±4.8 µIU/mL and 1.52±0.66, respectively) than in term newborns (7.9±2.7 µIU/mL and 1.19±0.29, respectively). Insulin was found to positively correlate with HOMA-IR, whereas cortisol was negatively correlated with HOMA-IR in both term and preterm newborns.

CONCLUSION

Higher insulin levels and HOMA-IR values in the cord blood of preterm newborns support the theory of intrauterine origin of metabolic diseases.

Cord Blood Levels of Insulin, Cortisol and HOMA2-IR in Very Preterm, Late Preterm and Term Newborns

INTRODUCTION

Alteration in the glucose homeostasis is still the major cause of morbidity and mortality in the newborns. Intrauterine undernutrition plays an important role in causing adult insulin resistance and diabetes but the exact cause is still unknown.

AIM

To estimate the plasma glucose, serum insulin and cortisol levels at birth in newborns at different gestational age.

MATERIALS AND METHODS

The present cross-sectional study conducted from December 2014 to June 2015 included 58 newborns enrolled as per the inclusion criteria and further categorized into Group I (very preterm; n=19; gestational age < 32 weeks), Group II (late preterm; n=20; gestational age between 32-37 weeks) and Group III (full term; n=19; gestational age >37 weeks) newborns. Venous Cord Blood (VCB) was collected and plasma glucose was analysed by GOD-POD (Glucose Oxidase-Peroxidase) method in auto analyser whereas serum insulin and cortisol were analysed by ELISA (Enzyme Linked Immunosorbent Assay). HOMA2-IR (Homeostatic Model Assessment) calculator was used to assess insulin resistance. All parametric data was expressed as mean±SD and analysed using ANOVA with Tukey's as the Post-Hoc test. Correlation analysis was done using Pearson's correlation co-efficient with scatter plot as the graphical representation.

RESULTS

Significantly increased insulin and HOMA2-IR levels were found in group I (13.7±4.7μIU/mL and 1.6±0.58 respectively) when compared to group II (8.3±2.9μIU/mL and 0.93±0.2 respectively) and group III (8.3±2.1μIU/mL and 1.03±0.26 respectively). A positive correlation between cortisol levels and gestational age (r = 0.6, n = 58, p < 0.001) and a negative correlation between insulin and gestational age (r = -0.654, n = 58, p < 0.001) was observed in the study population.

CONCLUSION

Increased levels of insulin and HOMA2-IR as seen in the very preterm newborns signify the predisposition of these newborns to development of diabetes in later stages of life. The inverse association of cortisol and insulin with gestational age suggests that cortisol could also be responsible for impaired β cell function and insulin sensitivity.

Arginine Vasopressin and Copeptin in Perinatology

Arginine vasopressin (AVP) plays a major role in the homeostasis of fluid balance, vascular tonus, and the regulation of the endocrine stress response. The measurement of AVP levels is difficult due to its short half-life and laborious method of detection. Copeptin is a more stable peptide derived from the same precursor molecule, is released in an equimolar ratio to AVP, and has a very similar response to osmotic, hemodynamic, and stress-related stimuli. In fact, copeptin has been propagated as surrogate marker to indirectly determine circulating AVP concentrations in various conditions. Here, we present an overview of the current knowledge on AVP and copeptin in perinatology with a particular focus on the baby's transition from placenta to lung breathing. We performed a systematic review of the literature on fetal stress hormone levels, including norepinephrine, cortisol, AVP, and copeptin, in regard to birth stress. Finally, diagnostic and therapeutic options for copeptin measurement and AVP functions are discussed.

Effect of Novel Melanocortin Type 2 Receptor Antagonists on the Corticosterone Response to ACTH in the Neonatal Rat Adrenal Gland In Vivo and In Vitro

Stress-induced increases in neonatal corticosterone demonstrate a unique shift from ACTH independence to ACTH dependence between postnatal day 2 (PD2) and day 8 (PD8) in newborn rats. This shift could be due to the binding of a bioactive, non--immunoreactive plasma ligand to the adrenocortical melanocortin 2 receptor (MC2R) (ACTH receptor). A potent MC2R antagonist would be useful to evaluate this phenomenon in the neonate. Therefore, we investigated the acute corticosterone response to ACTH(1-39) injection in rat pups pretreated with newly developed MC2R antagonists (GPS1573 and GPS1574), which have not been tested in vivo. The doses used in vivo were based on their in vitro potency, with GP1573 being more potent than GPS1574. GPS1573 (PD2 and PD8), GPS1574 (PD2 only), or vehicle were injected intraperitoneally (ip) 10 min before baseline sampling. Then, 0.001 mg/kg of ACTH(1-39) was injected ip, and subsequent blood samples obtained for the measurement of plasma corticosterone. Pretreatment of PD2 pups with GPS1573 demonstrated augmentation, rather than inhibition, of the corticosterone response to ACTH. In PD8 pups, pretreatment with 0.1 mg/kg GPS1573, but not 4 mg/kg, augmented the corticosterone response to ACTH. Pretreatment with GPS1574 attenuated the plasma corticosterone response to ACTH at 30 min in PD2 pups. The activity of these two compounds in vivo do not match their potency in vitro, with GPS1573 leading to a small augmentation of the corticosterone response to ACTH in vivo while GPS1574 resulted in inhibition.

Born from pre-eclamptic pregnancies predisposes infants to altered cortisol metabolism in the first postnatal year

Pre-eclampsia leads to disturbed fetal organ development, including metabolic syndrome, attributed to altered pituitary-adrenal feedback loop. We measured cortisol metabolites in infants born from pre-eclamptic and normotensive women and hypothesised that glucocorticoid exposure would be exaggerated in the former. Twenty-four hour urine was collected from infants at months 3 and 12. Cortisol metabolites and apparent enzyme activities were analysed by gas chromatography-mass spectrometry. From 3 to 12 months, excretion of THS, THF and pregnandiol had risen in both groups; THF also rose in the pre-eclamptic group. No difference was observed with respect to timing of the visit or to hypertensive status for THE or total F metabolites (P>0.05). All apparent enzymes activities, except 17α-hydroxylase, were lower in infants at 12 compared to 3 months in the normotensive group. In the pre-eclamptic group, only 11β-HSD activities were lower at 12 months.17α-hydroxylase and 11β-HSD activities of tetrahydro metabolites were higher in the pre-eclamptic group at 3 months (P<0.05). 11β-hydroxylase activity increased in the pre-eclamptic group at 12 months. Cortisol excretion, determined by increased 11β-hydroxylase, compensates for high 11β-HSD-dependent cortisol degradation at 3 months and at 12 months counterbalances the reduced cortisol substrate availability in infants born from pre-eclamptic mothers.

Priming for health: gut microbiota acquired in early life regulates physiology, brain and behaviour

The infant gut microbiome is dynamic, and radical shifts in composition occur during the first 3 years of life. Disruption of these developmental patterns, and the impact of the microbial composition of our gut on brain and behaviour, has attracted much recent attention. Integrating these observations is an important new research frontier.

CONCLUSION

Early-life perturbations of the developing gut microbiota can impact on the central nervous system and potentially lead to adverse mental health outcomes.