Microarray analysis of placental tissue in intrauterine growth restriction

OBJECTIVE

Besides foetal or maternal disorders, placental dysfunction is a major cause of intrauterine growth restriction (IUGR). Although numerous macro- and histopathological changes have been described, little is known about the precise aetiology and the contribution of foetal/placental genes in this disorder.

DESIGN

Placental tissues of 20 IUGR and control neonates were analysed by microarray technique. Four of the regulated genes with possible relevance in the pathogenesis of IUGR and its consequences were further studied in placentas of 27 IUGR and 35 control newborns.

RESULTS

Elevated gene expression of leptin, corticotrophin-releasing hormone (CRH), and IGF-binding protein-1 (IGFBP-1) in IUGR placentas could be confirmed in the larger group by real-time PCR, whereas prolactin showed no significant difference. Accordingly, protein expression of leptin and IGFBP-1 depicted by Western blot was elevated in IUGR, prolactin was not different. Birthweight standard deviation score (SDS) correlated negatively to leptin, IGFBP-1, and CRH, whereas placental weight correlated only to IGFBP-1. Leptin correlated negatively to gestational age of IUGR patients and positively to placental score, a marker of severity of impaired foeto-placental circulation.

CONCLUSIONS

As confirmed in a large group of IUGR and control samples, the up-regulated factors leptin, IGFBP-1, and CRH may serve as candidate genes for the prediction of subsequent metabolic consequences in IUGR newborns. These three factors may not only influence growth of the foetus, but might also interact with programming of its metabolic functions, which has to be determined in an ongoing study.

Differences in gene expression dependent on sampling site in placental tissue of fetuses with intrauterine growth restriction

OBJECTIVE

The human placenta as part of the feto-placental unit may influence fetal endocrine systems and may therefore represent a very important link between intrauterine growth restriction (IUGR) and metabolic disorders in later life. We aimed to analyze the effect of sample origin on gene expression of placental factors potentially involved in fetal programming in IUGR versus appropriate for gestational age growth (AGA) to standardize sample collection procedure for a multicenter approach.

DESIGN

Placental gene expression of insulin-like growth factor-binding protein (IGFBP)-1, prolactin, corticotropin releasing hormone (CRH) and leptin was measured and compared between proximal, intermediate and peripheral region of the placenta in 22 IUGR (proven by anomalous placental Doppler velocimetry) and 19 AGA neonates.

RESULTS

Whereas no difference in gene expression was seen in the proximal portion, in the intermediate placental region mRNA expression of IGFBP-1 (p = 0.01), prolactin (p = 0.04), CRH (p = 0.01) and leptin (p = 0.04) was increased in IUGR samples compared to controls. At the placental periphery, gene expression of these placental transcripts showed a higher expression level in IUGR placentas without statistical significance, except for leptin (p = 0.03).

CONCLUSION

Placental sampling site seems to be relevant for detecting differences in gene expression between IUGR and AGA neonates.

Very early extubation after open-heart surgery in children does not influence cardiac function

The objective of our study was to evaluate hemodynamic effects and the cardiac function after very early extubation within the first 6 hours after open-heart surgery in children. During a 12-month period, we performed a retrospective study of 50 children (ages 3 months to 7 years) admitted to the pediatric intensive care unit immediately after minor cardiac surgery. All children were extubated within the first 6 hours after their arrival. Arterial blood and central venous pressure were monitored, and arterial blood gas analysis was performed. Cardiac index, stroke volume index, systemic vascular resistance index, and extravascular lung water index were measured by thermodilution. Early extubation of children after minor open-heart surgery with cardiopulmonary bypass is safe and does not affect cardiac functions. A slight decrease of arterial oxygen tension not resulting in respiratory or metabolic acidosis or reintubation was noted. Very early extubation in children after open-heart surgery does not promote cardiodepressive effects. It is a safe procedure that helps to reduce the unnecessary and prolonged mechanical ventilation of children after cardiopulmonary bypass surgery.

Encouraging survival of infants with terminal renal failure combining dialysis and succeeding early transplantation

Dialysis in newborns and infants is a very challenging field in pediatric nephrology and still associated with high mortality. This article is designed for pediatricians who advise parents of newborns with renal failure. It aims to provide information about the difficulties during the period of dialysis and outcome after successful transplantation. We report upon five patients who proceeded to end-stage renal failure within the first year of life. All patients received peritoneal dialysis; however, two had to be switched to hemodialysis for several months. Four patients received percutaneous endoscopic gastric tubes (PEG) to enable high caloric diet. At the age of 1.5 to 5 years all children were successfully transplanted achieving good renal function. With regard to severe complications, hospitalisation time and somatic development all patients showed a substantial improvement after renal transplantation. Growth velocity increased to above SDS +2 after transplantation and all children reached the milestones of development in due time. In conclusion, after renal replacement therapy is initialised in infants with end-stage renal failure, sufficient nutrition to improve weight gain and to achieve the earliest possible transplantation is mandatory. Early transplantation results in a catch-up of developmental delay in short time.

Patient with antibody-negative relapse of Goodpasture syndrome

Smoking in young men may trigger anti-GBM disease manifesting with hemoptysis. We present a male adolescent in whom hemoptysis was mistaken to be a sign of airway infection for several months and who later on underwent an unusual antibody-negative relapse. The 16-year-old patient had a history of smoking and therapy-refractant hemoptysis and, later, acute macrohematuria with renal insufficiency necessitating hemodialysis (initial creatinine 4.2 mg/ dl). Chest X-ray showed diffuse lung infiltration. Renal biopsy revealed linear IgG deposits along the glomerular basement membrane (GBM) and cellular crescents in 13/16 glomeruli, simultaneously increased anti-GBM antibodies were detected. Thus, anti-GBM glomerulonephritis was diagnosed. After treatment with prednisone, oral cyclophosphamide and plasmapheresis, chest X-ray and hemoptysis improved, but renal failure persisted. Anti-GBM antibodies were negative. 4 weeks later, the patient presented again with a clinical relapse of severe hemoptysis and respiratory insufficiency after smoke exposition. Despite negative anti-GBM antibodies, he was treated similarly to a relapse and after the second course of plasmapheresis the patients' general condition improved and hemoptysis subsided. During the next 10 months the patient was stable with negative antibodies. He was under intermittent hemodialysis until laboratory measurements showed improved renal function. Now, 30 months after the acute episode, the patient is off dialysis for 17 months with stable creatinine values of 1.9 - 2.4 mg/dl, and is currently being treated with antihypertensive medicaments, calcitriol, calciumacetate, natriumhydrogencarbonate and allopurinol. The prognosis of anti-GBM glomerulonephritis depends on serum creatinine and the need of dialysis at initial presentation. In these patients, one-year survival rate is 67% and 5% for kidney function. Of note, despite the unfavorable prognosis in our patient, renal function recovered after 1 year of hemodialysis treatment. It is important to consider that in patients with anti-GBM disease antibody-negative relapses are possible.

Intrauterine growth retardation aggravates the course of acute mesangioproliferative glomerulonephritis in the rat

Intrauterine growth retardation (IUGR) aggravates the course of acute mesangioproliferative glomerulonephritis (GN) in the rat. Observational studies in children suggest that IUGR may be associated with a severe course of kidney diseases such as IgA nephropathy. We tested the hypothesis that IUGR leads to aggravation of acute mesangioproliferative GN in former IUGR rats. IUGR was induced in Wistar rats by isocaloric protein restriction in pregnant dams. Litter size was reduced to six male neonates in low protein animals (LP) and normal protein animals (NP). At 8 weeks GN was induced by injection of an anti-Thy-1.1 antibody. Rats were killed on days 4 and 14 after induction of GN and kidneys were investigated for inflammation and sclerosis using real-time polymerase chain reaction and histological methods. On day 4 after induction of GN, LP animals showed more glomerulosclerosis and tubulointerstitial lesions. On day 14, inflammatory markers (expression of monocyte chemoattractant protein 1, osteopontin, tumor necrosis factor and interleukin-6), extracellular matrix accumulation and markers of sclerosis (plasminogen activator inhibitor-1 expression, transforming growth factor-beta1 expression, score for glomerulosclerosis, glomerular deposition of collagen I and collagen IV) were more severe in LP animals. Some degree of induction of inflammatory and profibrotic markers was also present in non-nephritic LP animals. However, these rats did not display marked glomerulosclerosis or interstitial fibrosis. We conclude that after IUGR inflammatory damage is aggravated and the reparation of the kidney is impaired during the course of acute mesangioproliferative GN, leading to more sclerotic lesions.

Metabolic decompensation in children with type 1 diabetes mellitus associated with increased serum levels of the soluble leptin receptor

OBJECTIVE

Type 1 diabetes mellitus (T1DM) leads to increased serum levels of the soluble leptin receptor (sOB-R) by an as yet unknown cellular mechanism. The aim of our study was to investigate potential metabolic factors that may be associated with the induction of the sOB-R release from its membrane receptor.

MATERIALS AND METHODS

Twenty-five children (aged between 1.5 and 17.0 years) were studied at the onset of T1DM. Blood samples were collected before (n = 25), during the first 18 h (mean +/- S.D. 11.1 +/- 4.3 h, n = 16) and 92 h (47.5 +/- 22.5 h; n = 14) after beginning insulin therapy. Serum sOB-R and leptin levels were determined by in-house immunoassays.

RESULTS

The sOBR-level and the molar sOB-R/leptin ratio were significantly higher before than after starting insulin treatment (P < 0.05). In contrast, leptin levels were significantly lower (P < 0.05) before insulin therapy. The correlation between sOB-R and blood glucose (r = 0.49; P < 0.05), as well as sOB-R with parameters of ketoacidosis, such as pH (r = -0.72), base excess (r = -0.70), and bicarbonate (r = -0.69) (P < 0.0001) at diagnosis of T1DM remained significant during the first 18 h of insulin treatment. Multiple regression analysis revealed that base excess predicted 41.0% (P < 0.001), age 16.4% (P < 0.05), and height SDS 13.9% (P < 0.01) of the sOB-R variance.

CONCLUSIONS

Metabolic decompensation in children with new onset T1DM is associated with dramatic changes of the leptin axis; serum levels of sOB-R are elevated and of leptin are reduced. The molar excess of sOB-R over leptin (median 11.3) in this condition may contribute to leptin insensitivity. Upregulation of the soluble leptin receptor appears to be a basic mechanism to compensate for intracellular substrate deficiency and energy-deprivation state.

No evidence for angiotensin type 2 receptor gene polymorphism in intron 1 in patients with coarctation of the aorta and Ullrich-Turner syndrome

In male patients with congenital anomalies of the kidney and urinary tract, an increased incidence of a polymorphism in the angiotensin type 2 receptor gene (AT2R) has been identified. The AT2R has been shown to be involved in apoptosis, particularly during embryogenesis. The aim of this study was to examine the A-->1675G transition polymorphism in intron 1 of the AT2R gene that is located on the X chromosome in patients with coarctation of the aorta (CoA) with and without Ullrich-Turner syndrome (UTS). Screening of DNA samples was performed with restriction fragment length polymorphism analysis. Ninety-seven patients with CoA, 28 girls with UTS, 10 girls with UTS and CoA, and 96 control individuals were studied. There was no significant difference in the distribution of A and G-genotypes in any of the patient groups compared to controls. An A-->1675G transition in the AT2R gene seems not to be involved in the pathogenesis of aortic coarctation.

Absence of exercise-induced leptin suppression associated with insufficient epinephrine reserve in patients with classic congenital adrenal hyperplasia due to 21-hydroxylase deficiency

OBJECTIVE

Patients with congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency suffer from glucocorticoid and mineralocorticoid deficiency. They have insufficient epinephrine reserves and increased basal leptin levels and are often insulin resistant. In healthy subjects, an inhibitory effect of acute catecholamine elevation on the leptin plasma concentrations has been reported. However, it is not yet known how leptin levels respond to exercise in CAH patients.

METHODS

We performed a cycle ergometer test in six CAH patients to measure the response of plasma leptin, glucose and the catecholamines, epinephrine (E) and norepinephrine (N), as well as their respective metabolites, metanephrine (M) and normetanephrine (NM), to intense exercise.

RESULTS

Baseline leptin concentrations in CAH patients were not different from those of controls. Leptin levels decreased significantly with exercise in healthy controls, whereas they remained unchanged in CAH patients. In contrast to controls, CAH patients showed no rise of plasma glucose. Basal and stimulated E and M levels were significantly lower in CAH patients compared to controls. Baseline and stimulated N and NM levels were comparable, showing a significant rise after exercise. Peak systolic blood pressure and peak heart rate in both groups were comparable.

CONCLUSION

CAH patients do not manifest exercise-induced leptin suppression. The most probable reason for this is their severely impaired epinephrine stress response. In addition, epinephrine deficiency is leading to secondary changes in various catecholamine dependent metabolic pathways, e. g., energy balance. Although obvious clinical sequelae are so far unknown, the catecholamine-deficient state and the resulting hyperleptinemia might contribute to the severity of the disease in CAH.