scholarly journals β-arrestin expression in corticotroph tumor cells is modulated by glucocorticoids

2020 ◽  
Vol 245 (1) ◽  
pp. 101-113
Author(s):  
Federico Gatto ◽  
Richard A Feelders ◽  
Rob van der Pas ◽  
Peter van Koetsveld ◽  
Eleonora Bruzzone ◽  
...  

Pituitary-directed medical treatment for Cushing’s disease (CD) is currently represented by membrane receptor targeting drugs (somatostatin analogs and dopamine agonists). Somatostatin and dopamine receptors are regulated by β-arrestins, which have been shown to be differentially regulated by glucocorticoids in non-neuroendocrine cells. In this study we investigated the effects of glucocorticoids on β-arrestin expression in corticotroph tumor cells. First, AtT20 cells, a mouse model of CD, were exposed to dexamethasone (Dex) at different time points and β-arrestin expression was evaluated at mRNA and protein levels. Futhermore, β-arrestin mRNA expression was evaluated in 17 human corticotroph adenoma samples and correlated to patients’ pre-operative cortisol levels. We observed that Dex treatment induced a time-dependent increase in β-arrestin 1 mRNA expression and a decrease in β-arrestin 2. The same modulation pattern was observed at protein level. Dex-mediated modulation of β-arrestins was abolished by co-treatment with mifepristone, and Dex withdrawal restored β-arrestin expression to basal levels after 72 h. The evaluation of β-arrestin mRNA in corticotroph adenomas from CD patients with variable disease activity showed a significant positive correlation between β-arrestin 1 mRNA and urinary cortisol levels. The effect of glucocorticoids on β-arrestin levels was confirmed by the analysis of two samples from a single patient, which underwent adenomectomy twice, with different pre-operative cortisol levels. In conclusion, glucocorticoids induce an inverse modulation of the two β-arrestin isofoms in corticotroph tumor cells. Since β-arrestins regulate membrane receptor functions, this finding may help to better understand the variable response to pituitary-targeting drugs in patients with Cushing’s disease.

2004 ◽  
Vol 89 (3) ◽  
pp. 1131-1139 ◽  
Author(s):  
G. A. F. S. Rollin ◽  
N. P. Ferreira ◽  
M. Junges ◽  
J. L. Gross ◽  
M. A. Czepielewski

2014 ◽  
Vol 27 (11-12) ◽  
pp. 1043-1047 ◽  
Author(s):  
Julia Hoppmann ◽  
Isabel V. Wagner ◽  
Gudrun Junghans ◽  
Stefan A. Wudy ◽  
Michael Buchfelder ◽  
...  

Abstract Background: Cushing’s disease is very rare in children, and the diagnosis is frequently delayed by several years. Objective: We report a case of prepubertal Cushing’s disease with a medical history of only 9 months. This case illustrates the difficulties involved in diagnosing children at the early stage of the disease. Case presentation: An 8-year-old prepubertal boy presented with rapid weight gain accompanied by a decreasing growth velocity and hirsutism. Thyroid function tests and growth factor levels were normal, thus excluding hypothyroidism and growth hormone deficiency. Cushing’s syndrome was confirmed by elevated 24-h urinary free cortisol levels, increased diurnal cortisol levels, and a lack of cortisol suppression in the low-dose dexamethasone suppression test. Further tests to investigate the source of the hypercortisolism showed the following results: Basal morning adrenocorticotropic hormone (ACTH) was normal. The high-dose dexamethasone suppression test led to a 51% decrease in cortisol level. In the corticotropin-releasing hormone (CRH) test, ACTH and cortisol increased only by 28%. Repeated magnetic resonance imaging (MRI) finally revealed a microadenoma in the anterior pituitary, thus establishng the diagnosis of Cushing’s disease. Upon diagnosis, the patient underwent transsphenoidal surgery. Histological analysis confirmed an ACTH-secreting pituitary adenoma. Conclusion: This case illustrates the difficulties associated with the clinical, biochemical, and radiological diagnoses of Cushing’s disease in children. Early diagnosis remains a challenge because test results often do not match standard diagnostic criteria.


2020 ◽  
Vol 4 (Supplement_1) ◽  
Author(s):  
Vijaykumar Sekar ◽  
Joseph Hughes ◽  
Sugam Gouli

Abstract Background: Osteoporosis in post-menopausal women is usually due to bone loss from estrogen deficiency and/or age. Secondary osteoporosis (SO) is less common. Up to 30% of postmenopausal women and 50% of men with osteoporosis may have an underlying cause. Cushing’s disease (CD) is one cause of SO but rarely the presenting symptoms. The prevalence of osteoporosis (69.6% vs 37.8%) is significantly higher in patients with adrenal rather than pituitary CD. Diagnosing CD remains a challenge to physicians in spite of advances in diagnostic techniques. We report a case of CD in a post-menopausal woman presenting as accelerated osteoporosis. Clinical Case A 63-year-old Caucasian female with a history of hypertension and hysterectomy in her 50s on transdermal estrogen was referred to our Endocrine clinic for evaluation of osteoporosis and incidental finding of bilateral adrenal hyperplasia on CT spine. The patient rapidly developed kyphoscoliosis within the past 2 years. She was debilitated by pain and decreased mobility from compression fractures and spinal stenosis, and underwent thoracic and lumbar fusion surgery. On physical examination, her heart rate was 64 beats per minute, blood pressure 130/92 mmHg, weight 188 lbs. and Height 5.1 ft; a year ago it was 5.5 ft. Her face appeared round but not red. Buffalo hump and supraclavicular pad were noted. No striae or bruises noted. Healing surgical scars over the thoracic and lumbar spine were violaceous. The patient’s urine free cortisol levels, tested a month apart, were 190 mcg and 132 mcg (n 3.5-45 mcg/24h). Midnight salivary cortisol levels taken consecutive nights were 160 ng/dL and 513 ng/dL (n < 100 ng/dL). Morning Serum Cortisol and ACTH were 20.2 ug/dL and 14 pg/mL (n Cortisol 6.0-27.0 ug/dL and ACTH 7.2-63 pg/mL). Following low dose (1mg) dexamethasone suppression testing, her serum cortisol were 12.6 ug/dL, ACTH levels were 32 pg/mL and dexamethasone were 187 ng/dL (n < 30 ng/dL). 25-Hydroxy D total, TSH, Free T4, PTH intact, calcium, renin, aldosterone and SPEP levels were normal. Renal and liver functions were normal except alkaline phosphatase was 142 U/L (n 34-104 U/L). Pituitary MRI with contrast showed pituitary microadenoma. The patient was referred to a neurosurgeon and is planned for an inferior petrosal sinus sampling prior to transsphenoidal resection. Conclusion Cushing’s disease as a cause of osteoporosis is rare. Diagnosis of Cushing’s can be challenging in patients without obvious signs, as in our patient who was referred to an endocrinologist due to incidental finding of bilateral adrenal hyperplasia. A high degree of clinical suspicion is needed when investigating CD, as initial test results can be indecisive. As in our patient, initial ACTH and cortisol levels were normal, the low dose dexamethasone suppression test helped us direct our diagnosis towards CD.


1994 ◽  
Vol 130 (2) ◽  
pp. 125-131 ◽  
Author(s):  
Günter K Stalla ◽  
Steffi J Brockmeier ◽  
Ulrich Renner ◽  
Chris Newton ◽  
Michael Buchfelder ◽  
...  

Stalla GK, Brockmeier SJ, Renner U, Newton C, Buchfelder M, Stalla J, Müller OA. Octreotide exerts different effects in vivo and in vitro in Cushing's disease. Eur J Endocrinol 1994;130:125–31. ISSN 0804–4643 The effect of the long-acting somatostatin analog octreotide (SMS 201-995) on adrenocorticotropin (ACTH) secretion was studied in five patients with untreated Cushing's disease in vivo and in six human corticotropic adenoma cell cultures in vitro. For the in vivo study, 100 μg of octreotide sc was given 30 and 180 min after cannulation of the cubital vein and 100 μg of corticotropin-releasing hormone (CRH) was injected iv at 210 min. Serum ACTH and cortisol levels were measured for 390 min. In vivo, octreotide had no significant effect either on basal or CRH-stimulated ACTH levels and did not influence cortisol levels. The in vitro studies were conducted with corticotropic adenoma cell cultures derived from adenoma tissue obtained from six patients with Cushing's disease. In four of six cell cultures, octreotide (1 nmol/l–1 μmol/l) inhibited basal ACTH secretion in a dose-dependent manner. The inhibition ranged from 70 to 92% for 1 nmol/l octreotide to 14–46% for 1 μmol/l octreotide as compared to controls (100%). In three of three octreotide-responsive adenoma cell cultures investigated, CRH-stimulated ACTH secretion was suppressed by octreotide. Hydrocortisone pretreatment in vitro abolished the inhibitory effect of octreotide on ACTH secretion in one octreotide-responsive corticotropic adenoma cell culture. In conclusion, we showed that octreotide in most cases could inhibit the ACTH release from human corticotropic adenoma cells in vitro but had no suppressive effect on ACTH levels of patients with Cushing's disease in vivo. This discrepancy could be due to a somatostatin receptor down-regulation by cortisol at the hypercortisolemic state in vivo. Günter K Stalla, Max-Planck-Institute of Psychiatry, Clinical Institute, Kraepelinstr. 10, D-80804 Munich, Germany


2005 ◽  
Vol 153 (4) ◽  
pp. 535-543 ◽  
Author(s):  
Roberta Giordano ◽  
Andrea Picu ◽  
Uberto Pagotto ◽  
Rosaria De Iasio ◽  
Lorenza Bonelli ◽  
...  

Objective: Ghrelin exerts a wide spectrum of endocrine and non-endocrine actions. The stomach is the major source of circulating ghrelin levels that are negatively associated with body mass, insulin and glucose levels. The role of glucocorticoids in ghrelin secretion and action is still unclear. Design: In 8 patients with Cushing’s disease (CD, BMI 29.8 ± 1.6 kg/m2), 7 normal (NS) and 6 obese subjects (OB, BMI 32.9 ± 1.1 kg/m2) we studied: a) total ghrelin levels (every 15 min over 3 h) and their correlation with BMI, insulin, glucose, homeostatic model assessment (HOMA) index, ACTH and cortisol levels; b) GH, ACTH, cortisol, insulin and glucose responses to acylated ghrelin administration (1.0 μg/kg i.v. at 0 min). Results: CD patients had BMI, insulin and glucose levels as well as HOMA index higher than those in NS (P < 0.05) but similar to those in OB. Despite this, total ghrelin levels in CD were similar to those in NS and both were higher (P < 0.05) than those in OB. No correlation was found among total ghrelin and BMI, insulin, glucose, ACTH and cortisol levels in CD patients. The GH responses to ghrelin in CD and OB were similar and both were lower (P < 0.002) than those in NS. In CD ghrelin induced exaggerated ACTH and cortisol responses clearly higher (P < 0.005) than in OB and NS. Ghrelin administration increased glucose in all groups; insulin levels showed slight decrease that was significant (P < 0.05) in OB only. Conclusions: Hypercortisolism in humans is associated with impaired ghrelin secretion and action. In fact, total ghrelin secretion in CD is not reduced despite increased BMI, insulin and glucose levels, while the GH and ACTH responses to acylated ghrelin are clearly reduced and enhanced, respectively.


Author(s):  
Stephanie Wei Ping Wong ◽  
Yew Wen Yap ◽  
Ram Prakash Narayanan ◽  
Mohammad Al-Jubouri ◽  
Ashley Grossman ◽  
...  

Summary We report our experience on managing a case of florid Cushing’s disease with Methicillin-resistant Staphylococcus aureus (MRSA) sepsis using intravenous etomidate in the intensive care unit of a UK district general hospital. Learning points: Severe Cushing’s syndrome is associated with high morbidity and mortality. Etomidate is a safe and effective medical therapy to rapidly lower cortisol levels even in the context of severe sepsis and immunosuppression. Etomidate should ideally be administered in an intensive care unit but is still feasible in a district general hospital. During treatment with etomidate, accumulation of serum 11β-deoxycortisol (11DOC) levels can cross-react with laboratory cortisol measurement leading to falsely elevated serum cortisol levels. For this reason, serum cortisol measurement using a mass spectrometry assay should ideally be used to guide etomidate prescription.


2020 ◽  
Vol 182 (2) ◽  
pp. 207-217 ◽  
Author(s):  
John Newell-Price ◽  
Rosario Pivonello ◽  
Antoine Tabarin ◽  
Maria Fleseriu ◽  
Przemysław Witek ◽  
...  

Objective Monitoring of patients with Cushing’s disease on cortisol-lowering drugs is usually performed with urinary free cortisol (UFC). Late-night salivary cortisol (LNSC) has an established role in screening for hypercortisolism and can help to detect the loss of cortisol circadian rhythm. Less evidence exists regarding the usefulness of LNSC in monitoring pharmacological response in Cushing’s disease. Design Exploratory analysis evaluating LNSC during a Phase III study of long-acting pasireotide in Cushing’s disease (clinicaltrials.gov: NCT01374906). Methods Mean LNSC (mLNSC) was calculated from two samples, collected on the same days as the first two of three 24-h urine samples (used to calculate mean UFC [mUFC]). Clinical signs of hypercortisolism were evaluated over time. Results At baseline, 137 patients had evaluable mLNSC measurements; 91.2% had mLNSC exceeding the upper limit of normal (ULN; 3.2 nmol/L). Of patients with evaluable assessments at month 12 (n = 92), 17.4% had both mLNSC ≤ULN and mUFC ≤ULN; 22.8% had mLNSC ≤ULN, and 45.7% had mUFC ≤ULN. There was high variability in LNSC (intra-patient coefficient of variation (CV): 49.4%) and UFC (intra-patient CV: 39.2%). mLNSC levels decreased over 12 months of treatment and paralleled changes in mUFC. Moderate correlation was seen between mLNSC and mUFC (Spearman’s correlation: ρ = 0.50 [all time points pooled]). Greater improvements in systolic/diastolic blood pressure and weight were seen in patients with both mLNSC ≤ULN and mUFC ≤ULN. Conclusion mUFC and mLNSC are complementary measurements for monitoring treatment response in Cushing’s disease, with better clinical outcomes seen for patients in whom both mUFC and mLNSC are controlled.


2007 ◽  
Vol 51 (7) ◽  
pp. 1110-1117 ◽  
Author(s):  
Silvia R. Correa-Silva ◽  
Sérgio O. Nascif ◽  
Marcos R. Silva ◽  
Patrícia Molica ◽  
Ana-Maria J. Lengyel

GH responses to ghrelin, GHRP-6, and GHRH in Cushing’s disease (CD) are markedly blunted. There is no data about the effect of reduction of cortisol levels with steroidogenesis inhibitors, like ketoconazole, on GH secretion in CD. ACTH levels during ketoconazole treatment are controversial. The aims of this study were to compare the GH response to ghrelin, GHRP-6, and GHRH, and the ACTH and cortisol responses to ghrelin and GHRP-6 before and after one month of ketoconazole treatment in 6 untreated patients with CD. Before treatment peak GH (mg/L; mean ± SEM) after ghrelin, GHRP-6, and GHRH administration was 10.0 ± 4.5; 3.8 ± 1.6, and 0.6 ± 0.2, respectively. After one month of ketoconazole there was a significant decrease in urinary cortisol values (mean reduction: 75%), but GH responses did not change (7.0 ± 2.0; 3.1 ± 0.8; 0.9 ± 0.2, respectively). After treatment, there was a significant reduction in cortisol (mg/dL) responses to ghrelin (before: 30.6 ± 5.2; after: 24.2 ± 5.1). No significant changes in ACTH (pg/mL) responses before (ghrelin: 210.9 ± 69.9; GHRP-6: 199.8 ± 88.8) and after treatment (ghrelin: 159.7 ± 40.3; GHRP-6: 227 ± 127.2) were observed. In conclusion, after short-term ketoconazole treatment there are no changes in GH or ACTH responses, despite a major decrease of cortisol levels. A longer period of treatment might be necessary for the recovery of pituitary function.


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