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1.
Pituitary ; 26(5): 583-596, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37640885

ABSTRACT

PURPOSE: The Pituitary Society established the concept and mostly qualitative parameters for defining uniform criteria for Pituitary Tumor Centers of Excellence (PTCOEs) based on expert consensus. Aim of the study was to validate those previously proposed criteria through collection and evaluation of self-reported activity of several internationally-recognized tertiary pituitary centers, thereby transforming the qualitative 2017 definition into a validated quantitative one, which could serve as the basis for future objective PTCOE accreditation. METHODS: An ad hoc prepared database was distributed to nine Pituitary Centers chosen by the Project Scientific Committee and comprising Centers of worldwide repute, which agreed to provide activity information derived from registries related to the years 2018-2020 and completing the database within 60 days. The database, provided by each center and composed of Excel® spreadsheets with requested specific information on leading and supporting teams, was reviewed by two blinded referees and all 9 candidate centers satisfied the overall PTCOE definition, according to referees' evaluations. To obtain objective numerical criteria, median values for each activity/parameter were considered as the preferred PTCOE definition target, whereas the low limit of the range was selected as the acceptable target for each respective parameter. RESULTS: Three dedicated pituitary neurosurgeons are preferred, whereas one dedicated surgeon is acceptable. Moreover, 100 surgical procedures per center per year are preferred, while the results indicated that 50 surgeries per year are acceptable. Acute post-surgery complications, including mortality and readmission rates, should preferably be negligible or nonexistent, but acceptable criterion is a rate lower than 10% of patients with complications requiring readmission within 30 days after surgery. Four endocrinologists devoted to pituitary diseases are requested in a PTCOE and the total population of patients followed in a PTCOE should not be less than 850. It appears acceptable that at least one dedicated/expert in pituitary diseases is present in neuroradiology, pathology, and ophthalmology groups, whereas at least two expert radiation oncologists are needed. CONCLUSION: This is, to our knowledge, the first study to survey and evaluate the activity of a relevant number of high-volume centers in the pituitary field. This effort, internally validated by ad hoc reviewers, allowed for transformation of previously formulated theoretical criteria for the definition of a PTCOE to precise numerical definitions based on real-life evidence. The application of a derived synopsis of criteria could be used by independent bodies for accreditation of pituitary centers as PTCOEs.


Subject(s)
Pituitary Diseases , Pituitary Neoplasms , Humans , Pituitary Neoplasms/diagnosis , Pituitary Neoplasms/surgery , Pilot Projects , Pituitary Gland
3.
Pituitary ; 24(6): 943-953, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34173129

ABSTRACT

PURPOSE: Results are presented from 2 to 3 trials investigating oral octreotide capsules (OOC) as an alternative to injectable somatostatin receptor ligands (iSRLs) in the treatment of acromegaly. METHODS: CH-ACM-01 was an open-label trial (N = 155) and CHIASMA OPTIMAL was a double-blind placebo-controlled (DPC) trial (N = 56), both investigating OOC as maintenance therapy for patients with acromegaly who were biochemical responders receiving iSRLs. RESULTS: Baseline characteristics in both trials reflected those expected of patients with acromegaly responding to treatment and were similar between trials, despite differences in inclusion criteria. OOC demonstrated a consistent degree of biochemical response across trials, with 65% of patients in CH-ACM-01 maintaining response during the core period and 64% of patients in CHIASMA OPTIMAL at the end of the DPC. Mean insulin-like growth factor I (IGF-I) levels remained within inclusion criteria at the end of treatment in both trials. Of 110 patients entering the fixed-dose phase in CH-ACM-01, 80% maintained or improved acromegaly symptoms from baseline to the end of treatment. Over 85% of patients in both trials elected to continue into the extension phases. OOC were found to be well tolerated across both trials, and no dose-related adverse events were observed. CONCLUSIONS: OOC demonstrated remarkably consistent results for biochemical response, durability of response, and preference to continue with oral treatment across these 2 complementary landmark phase 3 trials, despite differences in the design of each. Trial registration NCT03252353 (August 2017), NCT01412424 (August 2011).


Subject(s)
Acromegaly , Human Growth Hormone , Acromegaly/drug therapy , Capsules , Humans , Insulin-Like Growth Factor I , Octreotide/therapeutic use , Somatostatin
4.
Eur J Endocrinol ; 174(2): P1-9, 2016 02.
Article in English | MEDLINE | ID: mdl-26563978

ABSTRACT

Recombinant human GH (rhGH) has been in use for 30 years, and over that time its safety and efficacy in children and adults has been subject to considerable scrutiny. In 2001, a statement from the GH Research Society (GRS) concluded that 'for approved indications, GH is safe'; however, the statement highlighted a number of areas for on-going surveillance of long-term safety, including cancer risk, impact on glucose homeostasis, and use of high dose pharmacological rhGH treatment. Over the intervening years, there have been a number of publications addressing the safety of rhGH with regard to mortality, cancer and cardiovascular risk, and the need for long-term surveillance of the increasing number of adults who were treated with rhGH in childhood. Against this backdrop of interest in safety, the European Society of Paediatric Endocrinology (ESPE), the GRS, and the Pediatric Endocrine Society (PES) convened a meeting to reappraise the safety of rhGH. The ouput of the meeting is a concise position statement.


Subject(s)
Consensus , Human Growth Hormone/adverse effects , Patient Safety/standards , Societies, Medical/standards , Adult , Child , Education , Endocrinology/standards , Europe , Humans , Pediatrics/standards , Recombinant Proteins
5.
Exp Clin Endocrinol Diabetes ; 123(8): 461-5, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26069074

ABSTRACT

BACKGROUND: Insulin-like Growth Factor-1 (IGF-1) and Insulin-like Growth Factor Binding Protein-3 (IGFBP-3) have been ascribed neuroprotective effects. We sought to determine whether levels of IGF-1 and IGFBP-3 predict functional outcome after ischemic stroke. METHODS: IGF-1 and IGFBP-3 levels were measured in the first week after stroke in patients with first ischemic stroke who were enrolled in the Berlin Cream&Sugar Study. National Institutes of Health Stroke Scale (NIHSS) was collected at admission. Lesion volume was determined from acute MRI if available. Functional outcome according to the modified Rankin Scale (mRS) was assessed after one year. In multivariate analyses we identified parameters associated with unfavourable functional outcome (mRS>2). RESULTS: We included 100 patients. 21 patients had an unfavourable functional outcome. IGF-1 levels were<- 2 standard deviation score (SDS) in 7 patients, and>2 SDS in 12 patients. IGFBP-3 levels werethe 95(th) percentile. Low levels of IGFBP-3 (p=0.002), NIHSS at admission (p=0.043) and age (p=0.001) were associated with unfavourable functional outcome in the univariate analyses. In multivariate analysis including IGFBP-3, IGF-1, age, thrombolysis and NIHSS only low IGFBP-3 levels (OR 7.2, 95%CI 1.8-29.0, p=0.006) were associated with unfavourable functional outcome. If lesion volume was incuded (n=71), only IGFBP-3 levels (OR 7.2, 95%CI 1.5-35.5, p=0.015) were associated with unfavourable functional outcome. CONCLUSION: IGFBP-3 levels after ischemic stroke may independently predict functional outcome after one year.


Subject(s)
Brain Ischemia/blood , Insulin-Like Growth Factor Binding Protein 3/blood , Stroke/blood , Aged , Brain Ischemia/diagnostic imaging , Female , Follow-Up Studies , Humans , Insulin-Like Growth Factor I/metabolism , Male , Middle Aged , Radiography , Stroke/diagnostic imaging
6.
Pituitary ; 18(5): 613-20, 2015 Oct.
Article in English | MEDLINE | ID: mdl-25492407

ABSTRACT

PURPOSE: Initial successful surgical treatment of pituitary adenomas is crucial to reach long-term remission. Indocyanine green (ICG) videoangiography (VA) is well established in vascular neurosurgery nowadays and several reports described ICG application in brain tumor surgery. We designed this study to evaluate the feasibility of intravenous application of ICG and visualisation of a pituitary lesion via the fluorescence mode of the operation microscope. METHODS: 22 patients with pituitary adenomas were treated with transsphenoidal microsurgery and were included in this study. Intraoperatively 25 mg ICG was administered intravenously and visualized via the fluorescence mode of the operation microscope (Pentero/Zeiss). RESULTS: 22 patients qualified for transsphenoidal surgery presenting with different clinical symptoms (13 patients with acromegaly, 6 with M. Cushing and 3 with other symptoms like vision disorder or dizziness) and identification of a pituitary lesion (21 of 22 patients) in preoperative MR-imaging (mean diameter: 9 mm; SD 3.6; 6 macroadenomas, 15 microadenomas, 1 MR-negative). In all 22 patients ICG VA was performed during surgery. No technical failures or adverse events after drug administration occurred. Visualization was optimal approximately 2.4 min after intravenous application. In all patients the adenoma could be detected via two different types of visualization: direct visualization by fluorophore emission versus indirect detection of the adenoma by a lower ICG fluorescence compared to the surrounding tissue. CONCLUSION: Our data show that intraoperative ICG VA can be a useful and easily applicable additional diagnostic tool for visualization of pituitary lesions using the microscopic approach.


Subject(s)
Adenoma/surgery , Angiography/methods , Coloring Agents/administration & dosage , Hypophysectomy/methods , Indocyanine Green/administration & dosage , Microscopy, Fluorescence , Microscopy, Video , Microsurgery/methods , Pituitary Neoplasms/surgery , Adenoma/blood supply , Adenoma/complications , Adenoma/pathology , Administration, Intravenous , Adolescent , Adult , Aged , Feasibility Studies , Female , Humans , Intraoperative Care , Magnetic Resonance Imaging , Male , Middle Aged , Pituitary Neoplasms/blood supply , Pituitary Neoplasms/complications , Pituitary Neoplasms/pathology , Predictive Value of Tests , Time Factors , Treatment Outcome , Young Adult
7.
Growth Horm IGF Res ; 23(3): 62-7, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23478141

ABSTRACT

OBJECTIVE: Human growth hormone (hGH), as well as the other members of the same polypeptide hormone family, have a four-helix bundle structure linked by two disulfide bridges, C53-C165 and C182-C189 in hGH. The C-terminal disulfide bridge of growth hormone is evolutionally conserved but its role is unknown. Our aim was to determine its importance for GH structure and/or function. DESIGN: We disrupted the highly conserved C-terminal disulfide bridge of hGH by substituting one or both of its cysteines by alanines. Mutant and wild type hGH genes were expressed in human embryonic kidney (HEK)-293 cells and the hGH analogs were characterized in vitro regarding biological activity, stability and binding to GH receptor (GHR) as well as GH binding protein (GHBP). RESULTS: Disrupting the hGH C-terminal disulfide bridge significantly reduces binding affinity to GHR and GHBP. If one of the cysteines is removed, the stability of the molecule is reduced but this feature is reversed when both cysteines are absent. However, despite decreased binding affinity and stability, biological activity is only modestly decreased when the disulfide bridge is removed. CONCLUSIONS: Our study reveals the importance of the C-terminal disulfide bridge of GH for receptor binding and the detrimental effect of its unpaired cysteines on stability as well as, to a lesser extent, biological activity. This improved knowledge of structure-function relationships helps better understand the biology of GH and related molecules. This could have an impact on diagnosis and treatment of patients with growth disorders.


Subject(s)
Carrier Proteins/metabolism , Disulfides/metabolism , Human Growth Hormone/metabolism , Receptors, Somatostatin/metabolism , STAT5 Transcription Factor/metabolism , Blotting, Western , Cell Proliferation , Fluorescent Antibody Technique , HEK293 Cells , Human Growth Hormone/genetics , Humans , Mutation/genetics , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , STAT5 Transcription Factor/genetics , Transcription, Genetic
8.
Pituitary ; 16(3): 294-302, 2013 Sep.
Article in English | MEDLINE | ID: mdl-22903574

ABSTRACT

In March 2011, the Acromegaly Consensus Group met to revise and update the guidelines on the diagnosis and treatment of acromegaly complications. The meeting was sponsored by the Pituitary Society and the European Neuroendocrinology Association and included experts skilled in the management of acromegaly. Complications considered included cardiovascular, endocrine and metabolic, sleep apnea, bone diseases, and mortality. Outcomes in selected, related clinical conditions were also considered, and included pregnancy, familial acromegaly and invasive macroadenomas. The need for a new disease staging model was considered, and design of such a tool was proposed.


Subject(s)
Acromegaly/complications , Acromegaly/diagnosis , Acromegaly/drug therapy , Bone Diseases/etiology , Cardiovascular Diseases/etiology , Endocrine System Diseases/etiology , Humans , Hypertension/etiology , Sleep Apnea Syndromes/etiology
9.
J Clin Endocrinol Metab ; 97(7): 2362-9, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22539587

ABSTRACT

CONTEXT: Oral administration of a novel octreotide formulation enabled its absorption to the systemic circulation, exhibiting blood concentrations comparable to those observed with injected octreotide and maintaining its biological activity. OBJECTIVES: The aim of the study was to determine oral octreotide absorption and effects on pituitary GH secretion compared to sc octreotide injection. DESIGN: Four single-dose studies were conducted in 75 healthy volunteers. INTERVENTION: Oral doses of 3, 10, or 20 mg octreotide and a single sc injection of 100 µg octreotide were administered. MAIN OUTCOME MEASURE: We measured the pharmacokinetic profile of orally administrated octreotide and the effect of octreotide on basal and stimulated GH secretion. RESULTS: Both oral and sc treatments were well tolerated. Oral octreotide absorption to the circulation was apparent within 1 h after dose administration. Escalating oral octreotide doses resulted in dose-dependent increased plasma octreotide concentrations, with an observed rate of plasma decay similar to parenteral administration. Both 20 mg oral octreotide and injection of 0.1 mg sc octreotide resulted in equivalent pharmacokinetic parameters [mean peak plasma concentration, 3.77 ± 0.25 vs. 3.97 ± 0.19 ng/ml; mean area under the curve, 16.2 ± 1.25 vs. 12.1 ± 0.45 h × ng/ml); and median time ≥ 0.5 ng/ml, 7.67 vs. 5.88 h, respectively). A single dose of 20 mg oral octreotide resulted in basal (P < 0.05) and GHRH-stimulated (P < 0.001) mean GH levels suppressed by 49 and 80%, respectively. CONCLUSIONS: The results support an oral octreotide alternative to parenteral octreotide treatment for patients with acromegaly.


Subject(s)
Human Growth Hormone/metabolism , Octreotide/administration & dosage , Octreotide/pharmacokinetics , Absorption , Administration, Oral , Adolescent , Adult , Antineoplastic Agents, Hormonal/administration & dosage , Antineoplastic Agents, Hormonal/adverse effects , Antineoplastic Agents, Hormonal/pharmacokinetics , Antineoplastic Agents, Hormonal/pharmacology , Cross-Over Studies , Dose-Response Relationship, Drug , Female , Human Growth Hormone/antagonists & inhibitors , Humans , Infusions, Parenteral , Infusions, Subcutaneous , Male , Middle Aged , Octreotide/adverse effects , Octreotide/pharmacology , Research Subjects , Treatment Outcome , Young Adult
11.
Exp Clin Endocrinol Diabetes ; 119(3): 156-62, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21086246

ABSTRACT

OBJECTIVE: To assess the efficacy of different dosing intervals of lanreotide, Somatuline Autogel® (Lan-ATG) 120 mg in patients with acromegaly, previously treated with octreotide, long-acting release (Oct-LAR). PATIENTS AND STUDY DESIGN: Patients previously on Oct-LAR 10, 20, or 30 mg were switched to 6 repeated deep subcutaneous injections of Lan-ATG 120 mg at intervals of 56, 42, or 28 days, respectively. After the third injection, dose intervals were adjusted on the basis of insulin-like growth factor 1 (IGF-1) levels. RESULTS: The ITT (Intention To Treat) population comprised 35 patients who received at least one dose of study medication and at least one post-baseline efficacy assessment. Overall, 62.9% (n=22) of patients had normalised IGF-1 levels with Lan-ATG at study end (one injection interval after the 6 (th) injection of Lan-ATG), which was similar to the proportion at baseline (60.0% [n=21]). QoL did not change from baseline to study end. Patient preference for Lan-ATG was highest in the 56-day dosing interval group: 71%, 54% and 41% of the patients in the 56, 42 and 28 day groups, respectively, expressed a preference for treatment with Lan-ATG (preference for Oct-LAR: 29%, 9% and 35%, respectively, while the remainder had no preference). CONCLUSION: Lan-ATG 120 mg injected at intervals of 56, 42 and 28 days provided equivalent hormonal control and QoL to Oct-LAR 10, 20 and 30 mg injected every 28 days, respectively. The proportion of patients preferring Lan-ATG treatment was greater in the longer injection interval groups.


Subject(s)
Acromegaly/drug therapy , Peptides, Cyclic/administration & dosage , Somatostatin/analogs & derivatives , Acromegaly/blood , Acromegaly/psychology , Dose-Response Relationship, Drug , Female , Human Growth Hormone/blood , Humans , Insulin-Like Growth Factor I/analysis , Male , Middle Aged , Octreotide/therapeutic use , Patient Satisfaction , Quality of Life , Somatostatin/administration & dosage , Surveys and Questionnaires
12.
Eur J Endocrinol ; 161 Suppl 1: S3-S10, 2009 Nov.
Article in English | MEDLINE | ID: mdl-19684061

ABSTRACT

Pivotal studies have demonstrated that pharmacotherapy with pegvisomant (Somavert) is a highly effective treatment for acromegaly. Since clinical experience with the drug was very limited, the Pegvisomant Observational Study was launched in Germany immediately with the drug becoming commercially available to patients early in 2004. Its purpose was to record safety and efficacy data on as many patients as possible. As of 12th August 2008 a total of 371 patients (185 males, 186 females) had been included in the study. They were on pegvisomant therapy for an average of 118 weeks. Median and mean doses of pegvisomant were 15 and 16.4 mg/day respectively. Treatment efficacy was monitored by IGF1 levels and the patients symptoms were evaluated by completion of a questionnaire (patient-assessed acromegaly symptom questionnaire). Safety data included liver function tests, fasting glucose, HbA1c measurements, and tumor size monitoring by repeated magnetic resonance imaging. Normalization of IGF1 ranged from 55.7% of the 273 patients assessed after 6 months to 71.3% of 202 patients assessed after 24 months of treatment. It was 70.7% after 36 months (133 patients), 64.8% at 48 months (71 patients), and 58.4% after 60 months (24 patients). In 39 patients (10.9%) treatment was discontinued due to serious adverse events or adverse events with 25 (6.7%) of these patients having a potential causal relationship with the pegvisomant treatment. Liver function tests became abnormal in 20 patients and another three patients were recorded to have hepatobiliary disorders. Tumor size increase was reported in 20 patients, but only confirmed in nine patients by careful revision of all available images. Local injection site reactions were observed in 12 patients. In conclusion, in this large group of pegvisomant-treated patients, long-term data for up to 5 years of treatment are now available. In 71.3% of patients with previously not sufficiently treatable acromegaly, IGF1 levels were normalized by pegvisomant therapy. Elevated transaminases usually normalized after discontinuation but in half of the affected patients also despite continuation of treatment without dose alteration. Tumor progression was a rare event. It did not exceed the expected rate in patients with acromegaly not treated with pegvisomant. As from this presently largest database of acromegalic patients treated with pegvisomant, long-term results are encouraging. The German data are now merged into the global ACROSTUDY and will constitute a major portion of the international ACROSTUDY project as a continuing global web-based observational study.


Subject(s)
Acromegaly/drug therapy , Growth Hormone-Secreting Pituitary Adenoma/complications , Hormone Antagonists/therapeutic use , Human Growth Hormone/analogs & derivatives , Insulin-Like Growth Factor I/metabolism , Pituitary Neoplasms/complications , Receptors, Somatotropin/antagonists & inhibitors , Acromegaly/blood , Acromegaly/etiology , Acromegaly/metabolism , Adolescent , Adult , Aged , Alanine Transaminase/blood , Aspartate Aminotransferases/blood , Biomarkers/blood , Blood Glucose/metabolism , Confounding Factors, Epidemiologic , Drug Administration Schedule , Female , Germany , Glycated Hemoglobin/metabolism , Growth Hormone-Secreting Pituitary Adenoma/pathology , Hormone Antagonists/administration & dosage , Hormone Antagonists/adverse effects , Human Growth Hormone/administration & dosage , Human Growth Hormone/adverse effects , Human Growth Hormone/therapeutic use , Humans , Liver/drug effects , Liver/metabolism , Liver Function Tests , Magnetic Resonance Imaging , Male , Middle Aged , Multiple Endocrine Neoplasia Type 1/complications , Pituitary Neoplasms/pathology , Population Surveillance , Sample Size , Young Adult
13.
Eur J Endocrinol ; 161(1): 27-35, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19411302

ABSTRACT

In treatment-resistant patients with acromegaly, pharmacotherapy with pegvisomant (Somavert) is a highly effective option. However, safety concerns have been raised related to a potential increase in tumor size during long-term pegvisomant treatment. Therefore, neuroradiological monitoring of tumor extension and volume was performed in the German Pegvisomant Observational Study, which covers 87% of patients treated with pegvisomant in Germany. As of 15 July 2007, a total of 307 patients (156 males and 151 females) had been included in the study and were on pegvisomant therapy for an average of 86.7 weeks. Median and mean doses of pegvisomant were 15 and 16.6 mg/day respectively. Out of these 307 patients, 18 were reported to have tumor-size increases as adverse events. From these 18 patients, all available serial magnetic resonance images were collected. Identical or similar sequences were chosen and the region of interest was magnified and compared across time after the best possible fit had been achieved by size and gray-scale correction. All available images were carefully re-evaluated according to this method. In 10 out of the 18 patients, there was no evidence of tumor-size increase, when the pre-treatment scans were compared with the most recent follow-up investigations. In two out of the remaining eight patients, there was a rebound effect observed after withdrawal of somatostatin analog treatment, but no further progression. In another three out of the eight patients, tumor-size increase had already been documented before pegvisomant treatment was commenced, during preceding somatostatin analog treatment and continued therapy. In the last three patients, tumor progression after the start of pegvisomant treatment was confirmed. All three patients had undergone pituitary surgery as primary treatment, but had not been pre-treated with radiotherapy. In all three cases, the tumor increase was not considered clinically significant and the investigators decided to continue pegvisomant treatment. In conclusion, in this large group of pegvisomant-treated patients, tumor progression was rare. It was reported in between 2 and 3% of patients treated, and did not exceed the expected rate in patients with acromegaly not treated with pegvisomant. In over one-half of patients, reports of tumor increase could not be confirmed by re-evaluation. This was mostly due to non-identical gantry projections. Misjudgements mainly occurred when only images from two individual investigations, rather than the entire series of scans, were compared. Thus, we recommend a careful serial evaluation of all available images to avoid misinterpretations and erroneous alerts. As from this presently largest database of acromegalic patients treated with pegvisomant, tumor-growth rate appears not to be different from patients on other treatment modalities. Although these data are reassuring with regard to the concern of somatotroph adenoma growth under peripheral GH receptor blockade, further study is required.


Subject(s)
Acromegaly/drug therapy , Acromegaly/pathology , Human Growth Hormone/analogs & derivatives , Pituitary Neoplasms/drug therapy , Pituitary Neoplasms/pathology , Acromegaly/epidemiology , Adult , Aged , Databases, Factual , Female , Follow-Up Studies , Germany/epidemiology , Human Growth Hormone/administration & dosage , Human Growth Hormone/adverse effects , Human Growth Hormone/blood , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Pituitary Neoplasms/epidemiology , Risk Factors
14.
Horm Metab Res ; 41(5): 356-62, 2009 May.
Article in English | MEDLINE | ID: mdl-19224431

ABSTRACT

With the beginning of puberty blood pressure increases and is persistently higher in men than in premenopausal women. Sex steroids are known to have complex effects on the renal and cardiovascular system and are involved in blood pressure regulation. The epithelial sodium channel (ENaC) modulates sodium reabsorption in the kidney, but little is known about sex-specific regulation of ENaC subunit expression. Regulation of the androgen receptor (AR) is known to be tissue-specific and age-dependent, but not well studied in the kidney. We investigated the effects of sex steroids on ENaC subunits and renal AR expression in an in vivo rat model. Ovariectomized female Wistar rats were treated with placebo, testosterone, 5 alpha-dihydrotestosterone (DHT) or 17 beta-estradiol (E2) for 14 days, and quantitative PCR and Western immunoblots were performed. DHT significantly decreased expression of all ENaC subunits in female rats, whereas testosterone showed only a trend to lower ENaC expression. These results are in contrast to previous studies where stimulating effects of androgens on the alpha-subunit of ENaC were seen. AR mRNA expression showed a trend to lower levels in females after testosterone treatment in this study. However, estrogen treatment significantly downregulated AR mRNA expression. In male control animals we were able to show a significantly increased expression of AR mRNA upon testosterone treatment. Our data demonstrate that AR and ENaC are regulated by sex steroids. That way sex steroids might modulate renal sodium reabsorption and therefore provide a possible explanation for sex differences in blood pressure.


Subject(s)
Epithelial Sodium Channels/genetics , Gene Expression Regulation , Kidney/metabolism , Receptors, Androgen/genetics , Animals , Epithelial Sodium Channels/metabolism , Female , Male , Random Allocation , Rats , Rats, Wistar , Receptors, Androgen/metabolism , Sex Characteristics , Species Specificity
15.
Clin Endocrinol (Oxf) ; 70(3): 439-45, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19067728

ABSTRACT

OBJECTIVE: At diagnosis, approximately 50% of adults with severe GH deficiency (GHD) have an IGF-I within the reference range. It is unclear whether in such patients serum IGF-I levels are regulated by factors other than GH. DESIGN AND PATIENTS: We performed a double-blind, randomized, placebo-controlled, cross-over study to investigate the effect of the GH receptor antagonist - pegvisomant (20 mg daily for 14 days) on GH and IGF-I levels in three cohorts: patients with GHD and a normal IGF-I (NORMS); patients with GHD and a low IGF-I (LOWS) and healthy volunteers (CONS). RESULTS: Pegvisomant decreased IGF-I in CONS and NORMS [158.5 (101-206) vs. 103 (77-125) microg/l, P < 0.01; 124 (81-136) vs. 95 (51-113) microg/l, P < 0.01 respectively], but not in LOWS [31 (< 31-32) vs. 34.5 (< 31-38) microg/l], and this was associated with an increase in mean 24 h GH in CONS [0.49 (0.12-0.89) to 1.38 (0.22-2.45) microg/l (P = 0.03)] and in NORMS [69 (0-320)% from 0.1 (< 0.1-0.13) to 0.17 (0.11-0.42) microg/l (P = 0.03)], but not in the LOWS. The peak GH response to arginine was increased by pegvisomant in CONS and NORMS [6.1 (0.8-9) vs. 20.4 (13.1-28.8) microg/l, P = 0.03; 0.4 (0.1-0.5) vs. 0.5 (0.3-0.6) microg/l, respectively], but not in LOWS. CONCLUSIONS: These data indicate that patients with severe GHD with a normal IGF-I are able to increase GH secretion in response to a pegvisomant-induced fall in IGF-I, whereas those with low IGF-I levels are unable to increase GH secretion. Therefore circulating IGF-I appears to be GH-independent in GHD patients with a low IGF-I, but remains partially GH-dependent in GHD patients with a normal IGF-I.


Subject(s)
Growth Disorders/drug therapy , Growth Disorders/metabolism , Growth Hormone/deficiency , Growth Hormone/metabolism , Human Growth Hormone/analogs & derivatives , Insulin-Like Growth Factor I/metabolism , Receptors, Somatotropin/antagonists & inhibitors , Adult , Body Composition , Cross-Over Studies , Double-Blind Method , Female , Growth Hormone/drug effects , Human Growth Hormone/pharmacology , Human Growth Hormone/therapeutic use , Humans , Insulin-Like Growth Factor I/drug effects , Male , Middle Aged
16.
Eur J Endocrinol ; 159(5): 525-32, 2008 Nov.
Article in English | MEDLINE | ID: mdl-18755874

ABSTRACT

BACKGROUND: Data on surgical and medical treatment outcomes in acromegaly mostly originate from specialized centers. We retrospectively analyzed the data on surgery, primary somatostatin analog (SSA) therapy, surgery preceded by SSA, and SSA preceded by surgery in 1485 patients from the German Acromegaly Register. METHODS: Two trained nurses visited all centers (N=42) for data acquisition. RESULTS: Primary surgery: out of 889 patients, 554 yielded analyzable data (microadenomas 22.9%, macroadenomas 77.1%). GH and IGF1 normalized in 54.3 and 67.2%. Partial or total pituitary insufficiency occurred in 28.6% initially and 41.2% post-surgery. Primary SSA (>or=3 months): out of 329 patients, 145 yielded analyzable data (microadenomas 26.7%, macroadenomas 73.3%). GH and IGF1 normalized in 36.3 and 30.5%, increasing to 40.8 and 41.5% with longer SSA (>or=360 days) in 54 patients. Pituitary function did not change. SSA (>or=3 months) prior to surgery: out of 234 patients, 93 yielded analyzable data. Post-surgery GH and IGF1 was normalized in 62.9 and 68.4%. GH improvement was slightly, but significantly better after SSA pretreatment. Surgery followed by SSA: out of 122 patients, 34 yielded analyzable data. GH and IGF1 normalized during SSA in 24.1 and 45.5%. Relative GH decrease was significantly larger compared with primary SSA. CONCLUSIONS: Pituitary surgery was more effective to lower GH and IGF1 concentrations than primary SSA. Primary SSA may be an option in selected patients. SSA prior to surgery only marginally improved surgical outcome. Debulking surgery may result in better final outcome in patients with a high GH concentration and a large tumor.


Subject(s)
Acromegaly/drug therapy , Acromegaly/surgery , Adenoma/drug therapy , Adenoma/surgery , Antineoplastic Agents, Hormonal/therapeutic use , Octreotide/therapeutic use , Acromegaly/pathology , Adenoma/pathology , Adolescent , Adult , Aged , Combined Modality Therapy , Female , Germany , Humans , Male , Middle Aged , Pituitary Gland/pathology , Registries , Retrospective Studies , Treatment Outcome
17.
Internist (Berl) ; 49(5): 527-8, 530-2, 534 passim, 2008 May.
Article in German | MEDLINE | ID: mdl-18418567

ABSTRACT

Patients with adult growth hormone deficiency apparently can develop a clinical picture with pronounced obesity, dyslipidemia, decreased bone density, and increased fracture rate as well as psychosocial limitations irrespective of the loss and replacement of further hypophyseal axes. The extent of these changes is strongly dependent on interindividual variations. Retrospective analyses have indicated a possibility of elevated morbidity and mortality among this patient cohort which can be due to the proatherogenic alterations (central obesity, dyslipidemia). Treatment with recombinant growth hormone in controlled trials resulted in evident improvement in quality of life, better body composition and lipid profile as well as an increase in bone density. Whether these improvements will also pay off in terms of reduction of endpoints (decline in fracture rates, decrease of cardiovascular morbidity and mortality) has not yet been confirmed by controlled studies. When administered at low doses, titrated according to the IGF-1 level, growth hormone replacement appears to be a safe and well-tolerated therapeutic regimen.


Subject(s)
Growth Hormone/deficiency , Growth Hormone/therapeutic use , Hormone Replacement Therapy/methods , Hormone Replacement Therapy/trends , Hypopituitarism/drug therapy , Outcome Assessment, Health Care , Pituitary Hormones/deficiency , Treatment Outcome
18.
Eur J Endocrinol ; 158(5): 623-30, 2008 May.
Article in English | MEDLINE | ID: mdl-18426820

ABSTRACT

UNLABELLED: Chronic exposure to hypercortisolism has significant impact on patient's health and health-related quality of life (HRQoL), as demonstrated with generic questionnaires. We have developed a disease-generated questionnaire to evaluate HRQoL in patients with Cushing's syndrome (CS; CushingQoL). OBJECTIVE: Validate the CushingQoL questionnaire in patients with CS in clinical practice conditions. DESIGN: Observational, international, cross-sectional study. METHODS: A total of 125 patients were recruited by 14 investigators from Spain, France, Germany, The Netherlands, and Italy over a 2-month period. Clinical and hormonal data were collected and correlated with results of the generic short form 36 (SF-36) questionnaire, a question on self-perceived general health status and the CushingQoL score. RESULTS: A total of 107 patients were pituitary-dependent and 18 adrenal-dependent CS; 104 (83%) were females, mean age 45 years (range 20-73 years); 39 (31%) were currently hypercortisolemic; and 47 (38%) adrenal insufficient. In clinical practice, CushingQoL was feasible (117; 94% of patients fully responded to the questionnaire in a mean time of 4 min), reliable (Crohnbach's alpha=0.87), and valid (factorial analysis demonstrated unidimensionality and Rasch analysis lead to a final version with 12 items). A significant (P<0.001) correlation was observed between CushingQoL score and patients self-perceived general health status and dimensions of SF-36 (Pearson's correlation coefficient > or =0.597). Patients with current hypercortisolism scored worse (lower) than those without (44+/-22 vs 56+/-21, P=0.004). Linear regression analysis identified female gender and hypercortisolism as significant predictors for worse QoL. CONCLUSION: CushingQoL is useful to evaluate HRQoL in patients with CS and correlates with clinical parameters.


Subject(s)
Cushing Syndrome/physiopathology , Cushing Syndrome/psychology , Health Status , Quality of Life , Surveys and Questionnaires/standards , Adult , Aged , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , Models, Statistical , Reproducibility of Results
20.
Horm Metab Res ; 39(7): 507-10, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17611903

ABSTRACT

OBJECTIVE: Insulinoma causes fasting hypoglycaemia due to inappropriate insulin secretion. The diagnosis of insulinoma is based on Whipple's triad during a supervised fasting test. The aim of our study was to evaluate retrospectively the percentage of positive 48-hour fasting tests in a large series of patients with insulinoma. DESIGN, PATIENTS AND METHODS: In a retrospective study, we identified 39 patients (24 females, 15 men; average age 47 years [range 12-78 years]) with insulinoma. Sixteen patients were diagnosed by spontaneous hypoglycaemia. Twenty-three patients with insulinoma were tested with a 48-hour fasting test and compared to 31 healthy controls who had a negative fasting test and were followed up for at least two years. RESULTS: The fast was terminated due to neuroglycopenic symptoms in 4 patients (17.4%) at the 12th hour, in 17 patients (73.9%) at the 24th hour, and in 22 patients (95.7%) at the 48th hour. One patient with insulinoma had no neuroglycopenic symptoms, but was diagnosed by glucose and insulin levels during the 48-hour fast. Healthy controls had significantly higher blood glucose and lower insulin levels, and a lower insulin-glucose ratio than patients with insulinoma at the end of the fast. CONCLUSIONS: In conclusion, the 48-hour fasting test was successful in the diagnosis of insulinoma in 95.7% of patients. In this series we did not observe a need for fasting beyond 48 hours.


Subject(s)
Fasting/physiology , Insulinoma/diagnosis , Adolescent , Adult , Blood Glucose , Child , Demography , Female , Humans , Insulin/blood , Male , Middle Aged , Retrospective Studies
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