Monika Obara-Moszynska

Assessment of ghrelin, GHS-R, GH, and neurohormones in human fetal pituitary glands and central nervous system: an immunohistochemical study.

The aim of this work was evaluation of expression of ghrelin and GHS-R1a receptor in somatotrops and in neuronal cells of brain tissue in the process of human fetal ontogenesis. Relations were also looked for between GHRH and SS in the pituitary and in the CNS neurones of the studied fetuses. The study was based on 8 pituitaries and 8 brains from fetuses in different periods of intrauterine life. The immunocytochemical technique was used. The presence of ghrelin, GHS-R was shown in the glandular part of the pituitary and CNS during the whole period of intrauterine life. Neurohormones in the stalk of the pituitary were found in fetuses from the 32nd week of pregnancy whereas in the CNS neurones these hormones could be detected throughout the whole period of intrauterine life. The results obtained suggest that stimulation of GH secretion by ghrelin is independent of the feedback concentration and these two hormones act like signals of metabolic balance. GH release by ghrelin in fetal life is independent of somatostatin. The hypothalamic-pituitary axis which regulates pulsatile GH release from the pituitary matures functionally in the third trimester of pregnancy independent of the previous anatomical differentiation.

Exome sequencing reveals two novel compound heterozygous XYLT1 mutations in a Polish patient with Desbuquois dysplasia type 2 and growth hormone deficiency

Desbuquois dysplasia type 2 (DBQD2) is a rare recessively inherited skeletal genetic disorder characterized by severe prenatal and postnatal growth retardation, generalized joint laxity with dislocation of large joints and facial dysmorphism. The condition was recently described to result from autosomal recessive mutations in XYLT1, encoding the enzyme xylosyltransferase-1. In this paper, we report on a Polish patient with DBQD2 who presented with severe short stature of prenatal onset, joint laxity, psychomotor retardation and multiple radiological abnormalities including short metacarpals, advanced bone age and exaggerated trochanters. Endocrinological examinations revealed that sleep-induced growth hormone (GH) release and GH peak in clonidine- and glucagon-induced provocative tests as well as insulin-like growth factor 1 (IGF-1) and IGF-binding protein-3 levels were all markedly decreased, confirming deficiency of GH secretion. Bone age, unlikely to GH deficiency, was significantly advanced. To establish the diagnosis at a molecular level, we performed whole-exome sequencing and bioinformatic analysis in the index patient, which revealed compound heterozygous XYLT1 mutations: c.595C>T(p.Gln199*) and c.1651C>T(p.Arg551Cys), both of which are novel. Sanger sequencing showed that the former mutation was inherited from the healthy mother, whereas the latter one most probably occurred de novo. Our study describes the first case of DBQD2 resulting from compound heterozygous XYLT1 mutation, expands the mutational spectrum of the disease and provides evidence that the severe growth retardation and microsomia observed in DBQD2 patients may result not only from the skeletal dysplasia itself but also from GH and IGF-1 deficiency.

NR0B1 ( DAX1 ) mutations in patients affected by congenital adrenal hypoplasia with growth hormone deficiency as a new finding

X-linked adrenal hypoplasia congenita (AHC,OMIM#300200) is a rare disorder of the adrenal cortex caused bymutations in the NR0B1 (DAX1) (dosage-sensitive sex reversal, adrenal hypoplasia critical region, on chromosome X, gene 1) gene (OMIM*300473). NR0B1 (DAX1) is located on the short arm of the X chromosome (Xp21.3-p21.2) and encodes for an orphan nuclear hormone receptor (transcription factor) (Zanaria et al. 1994). NR0B1 (DAX1) is expressed in the adrenals, gonads, hypothalamus, and pituitary gland, and it is responsible for controlling the development and function of these tissues. NR0B1 (DAX1) protein functions as a dominant negative regulator (transcriptional repressor) in the hypothalamic– pituitary–adrenal–gonadal axis. It regulates the expression of other proteins involved in the adrenal steroidogenesis pathway, such as steroidogenic factor 1 (SF-1), steroidogenic acute regulatory protein (StAR), P450scc and 3β-hydroxysteroid dehydrogenase (Lalli et al. 2000; Iyer and McCabe 2004). Almost 200 mutations in theNR0B1 (DAX1) gene have been identified to date (The Human Gene Mutation Database—data for 10.08.11) (http://www.hgmd.org). The most commonly found mutations in AHC patients are frameshift and nonsense mutations, which are located throughout the entire length of the NR0B1 (DAX1) gene. Missense mutations are not so common and are located mainly in the region that encodes for a ligandbinding domain at the C-terminus of the NR0B1 (DAX1) protein (Achermann et al. 2001a). Some patients have more complex X-chromosome rearrangements that include the deletion of larger parts of the X chromosome, including NR0B1 (DAX1), DMD (dystrophin), GK (glycerol kinase) and IL1RAPL (interleukin 1 receptor accessory protein-like) genes (Choi et al. 2005). AHC symptoms are noticed very early in postnatal life. The disorder is characterized by salt-wasting syndrome, hypoglycemia in early infancy or childhood, poor weight gain, vomiting, prolonged neonatal jaundice, and skin hyperpigmentation. In laboratory tests, hyponatremia, hyperkalemia, low levels of cortisol, aldosterone, and adrenal androgens are found, in contrast to high levels of adrenocorticotropic hormone (ACTH) and plasma renin activity (Achermann et al. 2000; Nakae et al. 1997; Wiltshire et al. 2001; Verrijn Stuart et al. 2007). Very frequently, patients are admitted to hospital in a life-threatening condition. AHC is lethal unless appropriate steroid replacement therapy is provided to these patients. Most patients with AHC also suffer from hypogonadotropic hypogonadism, since mutations in the NR0B1 (DAX1) gene A. Rojek (*) :M. Niedziela 2nd Chair of Pediatrics, Department of Pediatric Endocrinology and Rheumatology, Molecular Endocrinology Laboratory, Poznan University of Medical Sciences, 27/33 Szpitalna Street, 60-572 Poznan, Poland e-mail: aleksandra.rojek@gmail.com

Growth hormone therapy in a girl with Turner syndrome and diabetes type 1 - case report.

INTRODUCTION The studies indicate the complex etiology of abnormal glucose metabolism in the Turner syndrome (TS). In the light of these carbohydrate disorders a therapy with recombinant growth hormone (rGH) in TS may be associated with complications, as growth hormone has a diabetogenic potential. PATIENT REPORT Perinatal history is unknown since the patient was adopted at the age of 4 years. At 11 years old, due to typical phenotype, TS was diagnosed. The karyotype was 45,X[43]/46,X,i(X)(q10)[7]. At the same age, basing on laboratory results, insulin dependent diabetes was diagnosed and the conventional insulin therapy was initiated. During the hospitalization, at the age of 12 years, the patient was 123.5cm (-4.4SD). At the same age rGH tre-atment was initiated, with the dose 0.045 mg/kg/d. After 3 months of therapy the height velocity rose to 8.2 cm/ year. At the age of 13 years, substitution with 17β-estradiol was started. After 3 years and 4 months the growth hormone treatment was stopped because of poor height velocity. The final height of the patient was 140 cm (-4,OSD). Two years after the end of rGH treatment the height was 141.2 cm. After termination of rGH treatment the need for daily insulin dose decreased from 50-60U/d to 38-44U/d. CONCLUSIONS The decision of rGH therapy in TS with diabetes is certainly difficult. While starting the growth hormone treatment the clinician must keep in mind the risk of metabolic complications, but also the awareness that gives the patient a chance to improve the final height. In terms of the proper psycho-emotional development the reduction of growth deficit is very important.

The usefulness of the GHRH stimulation test in the diagnostics of growth hormone deficiency in children

INTRODUCTION Stimulation tests form the basis for the diagnostic process in growth hormone deficiency (GHD). One of these tests uses the GH releasing hormone (GHRH). This provides the potential to differentiate patients with pituitary dysfunction from patients with hypothalamus abnormalities. However, the routine use of the GHRH test is still being debated. The aim of this study was to assess the diagnostic usefulness of the GHRH test in the diagnostics of GHD. MATERIAL AND METHODS The study group consisted of 20 prepubertal children with GHD. In all the children, one of the performed stimulation tests was the GHRH test. RESULTS The results showed that the mean peak concentration of GH in the GHRH test was 14.7 ± 11.3 ng/mL. In eight children the MRI showed pituitary hypoplasia, in one patient pituitary hypoplasia and pituitary stalk agenesis, and in one patient septo-optic dysplasia. All patients with pituitary malformations, except for one patient with a hypoplastic pituitary gland, presented GH levels < 10 ng/mL in the GHRH test. The sensitivity of the GHRH test in the diagnostics of GHD was 45%. CONCLUSIONS The high correlation between the GHRH test and anatomical changes in the pituitary provides this test with a high predictive value. In individual clinical cases, knowledge about the level of damage in the hypothalamic-pituitary area can determine diagnostic and therapeutic procedures.

Treatment of cartilage-hair hypoplasia with recombinant human growth hormone.

Cartilage–hair hypoplasia (CHH) is an autosomal recessive disorder characterized by short stature, hypoplastic hair and humoral immunity disorders. It is a mutation in the RMRP gene, located on chromosome 9p13.3, that leads to CHH. There is no special treatment for short stature in CHH. The efficacy and safety of recombinant human growth hormone (rhGH) therapy in CHH is still under discussion. The present study describes the case of a girl with CHH who was treated with rhGH. The rhGH treatment had a significant effect on the height gain: the height SD score was changed from −4. to −2.98 after 4 years 7 months of treatment. rhGH therapy should be considered as a treatment modality for CHH, and insulin‐like growth factor (IGF)‐1 and IGF‐binding protein 3 concentrations should be closely monitored, particularly because of the increased cancer risk that is a characteristic feature of CHH.

Expression of ghrelin in human fetal adrenal glands and paraadrenal nerve ganglions

The aim of this paper was assessment of location, expression and role of ghrelin in the development and maturation of human fetal adrenal glands and paraadrenal nerve ganglions. Immunohistochemistry was used. The strongest expression of ghrelin was detected in the fetal zone of the adrenal glands, in the neuroepithelial cells of the medullar portion of the adrenals and in few nerve ganglion cells. Ghrelin takes part in molecular processes of proliferation and maturation, and does not influence on steroidogenesis.

The Usefulness of Magnetic Resonance Imaging of the Cardiovascular System in the Diagnostic Work-Up of Patients With Turner Syndrome

Cardiovascular defects occur in 50% of patients with Turner syndrome (TS). The aim of the study was to estimate the usefulness of cardiac magnetic resonance imaging (CMR) and magnetic resonance angiography (angio-MR) as diagnostics in children and adolescents with TS. Forty-one females with TS, aged 13.9 ± 2.2 years, were studied. CMR was performed in 39 patients and angio-MR in 36. Echocardiography was performed in all patients. The most frequent anomalies diagnosed on CMR and angio-MR were as follows: elongation of the ascending aorta (AA) and aortic arch, present in 16 patients (45.7%), a bicuspid aortic valve (BAV), present in 16 patients (41.0%), and partial anomalous pulmonary venous return (PAPVR), present in six patients (17.1%). Aortic dilatation (Z-score > 2) was mostly seen at the sinotubular junction (STJ) (15 patients; 42.8%), the AA (15 patients; 42.8%), the thoracoabdominal aorta at the level of a diaphragm (15 patients; 42.8%), and the transverse segment (14 patients; 40.0%). An aortic size index (ASI) above 2.0 cm/m2 was present in six patients (17.1%) and above 2.5 cm/m2 in three patients (8.6%). The left ventricular end-diastolic volume (EDV), end-systolic volume (ESV), and stroke volume (SV) were diminished (Z-score < −2) in 10 (25.6%), 9 (23.1%), and 8 patients (20.5%), respectively. A webbed neck was correlated with the presence of vascular anomalies (p = 0.006). The age and body mass index (BMI) were correlated with the diameter of the aorta. Patients with BAV had a greater aortic diameter at the ascending aorta (AA) segment (p = 0.026) than other patients. ASI was correlated with aortic diameter and descending aortic diameter (AD/DD) ratio (p = 0.002; r = 0.49). There was a significant correlation between the right ventricular (p = 0.002, r = 0.46) and aortic diameters at the STJ segment (p = 0.0047, r = 0.48), as measured by echocardiography and CMR. Magnetic resonance can identify cardiovascular anomalies, dilatation of the aorta, pericardial fluid, and functional impairment of the ventricles not detected by echocardiography. BMI, age, BAV, and elongation of the AA influence aortic dilatation. The ASI and AD/DD ratio are important markers of aortic dilatation. The performed diagnostics did not indicate a negative influence of GH treatment on the cardiovascular system.

Molecular Detection and Incidence of Y Chromosomal Material in Patients with Turner Syndrome

The presence of a Y chromosome in patients with Turner syndrome (TS) is a risk factor for the development of gonadal tumor and/or virilization. With conventional cytogenetic analysis, some cells containing a Y chromosome can be missed. The aim of this study was to determine the presence and incidence of Y chromosome-derived material in TS patients using PCR and the markers SRY, DYZ1, DYZ3, DYS132, ZFY, and TSPY. Fifty-five TS patients (aged 5.5-26.75 years) were analyzed. A total of 17/55 (30.9%) were Y-positive, but only 7/17 had a Y chromosome in their karyotype and underwent gonadectomy. In 2 of these patients (28.6%), histopathologic examination revealed gonadoblastoma and dysgerminoma, respectively. In 8 patients in the studied group (8/55; 14.5%), the TSPY gene was detected, and the SRY gene (or a fragment) was identified in 9(3)/55 patients. No coding region mutations were observed in these SRY-positive patients. In conclusion, we have shown a high prevalence of Y chromosomal material in TS. Y markers were also observed in patients who had no Y chromosome in their karyotype, and PCR is very precise in detecting the presence of genetic material from the Y chromosome. Further follow-up of these Y-positive TS patients is mandatory.