Neurodevelopmental outcomes of very preterm infants born following early foetal growth restriction with absent end-diastolic umbilical flow

This study aims to assess the impact of time of onset and features of early foetal growth restriction (FGR) with absent end-diastolic flow (AEDF) on pregnancy outcomes and on preterm infants' clinical and neurodevelopmental outcomes up to 2 years corrected age. This is a retrospective, cohort study led at a level IV Obstetric and Neonatal Unit in Bologna, Italy. Pregnant women were eligible if having singleton pregnancies, with no major foetal anomaly detected, and diagnosed with early FGR + AEDF (defined as FGR + AEDF detected before 32 weeks gestation). Early FGR + AEDF was further classified according to time of onset and specific features into very early and persistent (VEP, FGR + AEDF first detected at 20-24 weeks gestation and persistent at the following scans), very early but transient (VET, FGR + AEDF detected at 20-24 weeks gestation and progressively improving at the following scans) and later (LA, FGR + AEDF detected between 25 and 32 weeks gestation). Pregnancy and neonatal outcomes and infant follow-up data were collected and compared among groups. Neurodevelopment was assessed using the revised Griffiths Mental Developmental Scales (GMDS-R) 0-2 years. A regression analysis was performed to identify early predictors of preterm infants' neurodevelopmental impairment. Fifty-two pregnant women with an antenatal diagnosis of early FGR + AEDF were included in the study (16 VEP, 14 VET, 22 LA). Four intrauterine foetal deaths occurred, all in the VEP group (p = 0.010). Compared to LA infants, VEP infants were born with lower gestational age and lower birth weight, had lower arterial cord blood pH and were at higher risk for intraventricular haemorrhage and periventricular leukomalacia (p < 0.05 for all comparisons). At 12 months, VEP infants had worse GMDS-R scores, both in the general quotient (mean [SD] 91.8 [12.4] vs 104.6 [8.7] in LA) and in the performance domain (mean [SD] 93.3 [15.4] vs 108.8 [8.8] in LA). This latter difference persisted at 24 months (mean [SD] 68.3 [17.0] vs 92.9 [17.7] in LA). In multivariate analysis, at 12 months corrected age, PVL was found to be an independent predictor of impaired general quotient, while the features and timing of antenatal Doppler alterations predicted worse scores in the performance domain.Conclusion: Timing of onset and features of early FGR + AEDF might impact differently on neonatal clinical and neurodevelopmental outcomes. Shared awareness of the importance of FGR + AEDF features between obstetricians and neonatologists may offer valuable tools for antenatal counselling and for tailoring pregnancy management and neonatal follow-up in light of specific antenatal and neonatal risk factors

Hypothalamic ghrelin treatment modulates NPY-but not CRH-ergic activity in adrenalectomized rats subjected to food restriction: Evidence of a novel hypothalamic ghrelin effect

It has been proposed that ghrelin induces food intake by a mechanism due to the stimulation of hypothalamic NPY-ergic activity. It is recognized that bilateral adrenalectomy (ADX) enhances hypothalamic CRH-ergic function and reduces appetite. Thus, the aim of the present study was to test whether, icv-administered, ghrelin modulates NPY- and CRH-ergic functions after food restriction (FR) and glucocorticoid deprivation. For this purpose, 1 microg ghrelin was administered icv to ad libitum (AL) eating and to corticosterone (B)-depleted (ADX) and -replete (sham and ADX+B) male animals habituated, for 15 d, to FR. Food intake, hypothalamic function, and peripheral ghrelin, ACTH, and B concentrations were evaluated 2 h after ghrelin administration. Results indicate that while icv ghrelin treatment stimulated 2-h food intake in AL rats, it failed to do so in sham- and ADX+B-FR animals; moreover, 2-h food intake was inhibited by icv ghrelin treatment in ADX-FR rats. Regarding peripheral hormone levels: (a) basal circulating ghrelin levels, already enhanced (vs AL rats) by FR, significantly increased 2 h after icv ghrelin treatment in AL and sham-FR rats; (b) central ghrelin treatment stimulated ACTH secretion in circulation of AL and glucocorticoid-replete-FR rats; and (c) B circulating levels remained unchanged after ghrelin treatment, although they were in relation to the food intake condition of rats. Finally, hypothalamic NPY mRNA expression was enhanced by FR and, in response to icv ghrelin treatment, it decreased in ADX-FR rats only. ADX-enhanced hypothalamic CRH mRNA levels were reduced by ghrelin icv administration only when animals received B replacement therapy. Our data indicate an inhibitory effect of hypothalamic ghrelin on NPY-ergic activity in FR rats lacking endogenous glucocorticoid

Bilateral adrenal enucleation-induced changes in adenohypophyseal pro-opiomelanocortin (POMC)-related peptides synthesis and secretion: A comparative study with adrenalectomized rats

The aim of the present study was to elucidate the modulatory effect of transient changes in endogenous glucocorticoids, occurring after bilateral adrenal enucleation (ENUC), on anterior pituitary (AP) proopiomelanocortin (POMC)-derived peptides synthesis and output in rats. For this purpose, adult female rats were either bilaterally ENUC, adrenalelectomized (ADX), or sham-operated (SHAM) and killed by decapitation 2, 7, 14, and 21 days after surgery. Trunk blood was collected for measurements of ACTH, β-endorphin (β-END) and corticosterone (B) concentrations; APs were quickly dissected for the determination of ACTH, β-endorphin (β-END)-like (β-END-LI) and γ3-MSH contents and adrenal glands were removed and submitted to histological study. The results indicate that ENUC and ADX increased AP POMC-related peptides synthesis and release in association with changes in the AP processing of peptides belonging to the N-terminal (γ3-MSH), mid (ACTH) and C-terminal (β-LPH/ENDs) portions of POMC. While ADX abolished plasma B levels, ENUC induced a transient (day 2) decrease in plasma B concentrations which returned to SHAM levels at 7 days after surgery. These data tallied with the histological observations carried out, indicating a time-dependent regenerative process of the adrenal which was completed by three weeks after ENUC. There was a different pattern in plasma ACTH and β-END levels between ENUC and ADX; maximal plasma peptide levels were found 7–14 days after ENUC, then falling down to SHAM values at 21 days post ENUC. Conversely, there was a constant increment in plasma peptide levels up to 21 days after ADX. At 2 days after both ENUC and ADX all peptides measured in the AP were lower than SHAM values, thus reflecting a rapid corticotrope secretion. Thereafter, 7 or more days after surgery, AP peptide content in ADX rats increased, in a time-related fashion, up to 21 days after surgery. Only β-END-LI showed a similar AP content to that of the SHAM group, thereafter indicating a preferential cleavage of POMC to β-END long after ADX (21 days). ENUC rats showed increased AP POMC peptides content throughout the whole time, and it was significantly different from SHAM and ADX values 14 days post-surgery. Interestingly, we found an increment in AP γ3-MSH, a peptide which is preferentially synthesized in the intermediate lobe of the rat pituitary, in both ENUC and ADX situations. Our results further indicate that: 1) glucocorticoids, from regenerating adrenal origin, induce a fast negative feedback mechanism on AP secretion, and 2) there might be a delayed inhibitory action of newly synthesized corticosteroids on higher levels of the central nervous system. The lack of glucocorticoids (ADX) clearly corroborates a persistent enhancement of AP POMC-related peptides synthesis and secretion. The differences in AP processing of POMC between ENUC and ADX might be due to qualitative/quantitative changes in hypotalamic ACTH secretagogues output.Facultad de Ciencias Médica

Sexual dimorphism in the mouse hypothalamic-pituitary-adrenal axis function after endotoxin and insulin stresses during development

Bidirectional communication between the immune and the endocrine systems is now widely accepted as essential for the survival of the organism. Since a classical nonresponsive period of the hypothalamic-pituitary-adrenal (HPA) axis takes place shortly after birth and because endogenous sex hormones modulate immune function, the aim of the present work was to determine whether sex steroids regulate the PHA axis response to immune (bacterial, lipopolysaccharide, LPS) and nonimmune (insulin, INS) stressors in mice during development. For this purpose 7-, 15-, 30-, 45- and 60-day-old mice of both sexes were intraperitoneally injected with either vehicle alone (basal) or containing LPS (2 mg/kg body weight) or INS (12 IU/kg body weight). The animals were then killed by decapitation, 2 h or 45 min after LPS or INS, respectively. Plasma samples were assayed to measure corticosterone concentrations. The results indicated that: (a) there was a transient increase in basal plasma corticosterone levels during development, with a peak value at the juvenile age, regardless of sex; (b) a higher basal plasma corticosterone concentration in females than in males characterized the adult age; (c) the infantile age is a period of the HPA axis function nonresponsive to purely neuroendocrine but not to inflammatory stimuli; (d) during the juvenile age, females showed a hyporesponsive HPA axis to neurendocrine and immune stress, whereas male mice were fully unresponsive to both challenges; (e) animals of both sexes showed a maximal HPA axis response to purely neuroendocrine stress at the prepubertal age; this response to the immune stimulus was also maximal in 30-day-old males, while it was found in females after puberty (45-day-old mice); (f) sexual dimorphism in the HPA axis response to a purely neuroendocrine stimulus was found at 30 days of age or later, while this characteristic of the response to endotoxin was not present until puberty. These data clearly suggest that these are gender-dependent characteristics of the ontogeny of the HPA and HP-gonadal axes that are responsible for the sexual dimorphism of HPA axis function in mice

Calpain involvement in calphostin C-induced apoptosis

A major problem in assessing the role of calpains in apoptosis induction concerns the fact that calpain inhibitors can also impair the activity of the proteasome, also reported to be involved in apoptosis. Herein we showed that apoptosis induced by calphostin C in U937 human promonocytic leukemia cells was associated, at its onset, with enhanced protein (poly)ubiquitination. This observation prompted us to study whether protein degradation through the ubiquitin/proteasome pathway was involved in apoptosis induction. We found that N-acetyl-Leu-Leu-norleucinal (50 microM), a proteasome as well as a calpain inhibitor, was able to reduce calphostin C-induced apoptosis by approximately 60%, whereas lactacystin (10 microM), a specific proteasome inhibitor, was ineffective. These results suggest that calphostin C-induced apoptosis is partly calpain-mediated, but does not require protein degradation through the ubiquitin/proteasome pathway