Classic and Recent Etiologies of Cushing??s Syndrome

Corticotropin-releasing hormone test predicts the outcome of unilateral adrenalectomy in primary bilateral macronodular adrenal hyperplasia

PURPOSE

Primary bilateral adrenal hyperplasia (PBMAH) is associated with hypercortisolism and a heterogeneous clinical expression in terms of cortisol secretion and related comorbidities. Historically, treatment of choice was bilateral adrenalectomy (B-Adx); however, recent data suggest that unilateral adrenalectomy (U-Adx) may be an effective alternative. For the latter, factors predicting the postsurgical outcome (e.g., biochemical control) have not been identified yet.

METHODS

PBMAH patients undergoing U-Adx for overt Cushing's syndrome (CS) in two tertiary care centers were retrospectively analysed. Remission was defined as a normalization of urinary free cortisol (UFC) without the need for medical treatment. The potential of hCRH test as a predictor of U-Adx outcome was evaluated in a subgroup.

RESULTS

23 patients were evaluated (69% females, mean age 55 years). Remission rate after U-Adx was 74% at last follow up (median 115 months from UAdx). Before U-Adx, a positive ACTH response to hCRH (Δ%ACTH increase > 50% from baseline) was associated with higher remission rates.

CONCLUSIONS

Three of four patients with PBMAH are surgically cured with U-Adx. Pre-operative hCRH testing can be useful to predict long-term remission rates.

Onset of Aortic Dissection Complicated with Cushing's Disease: A Case Report and Review of the Literature

Cushing's syndrome and Cushing's disease cause various metabolic disorders associated with high cortisol levels. Some reports have shown that Cushing's syndrome is complicated with dissecting aortic aneurysm and aortic dissection after long-term exposure to high cortisol levels. We herein report a rare case of aortic dissection complicated with Cushing's disease. Aortic dissection may occur even under relatively short periods of high cortisol conditions. This case suggests that hypercortisolemia should be treated as soon as possible in order to prevent aortic dissection in subjects with Cushing's disease.

[Modern aspects of surgery for cushing's disease]

Cushing's disease is a severe neuroendocrine disorder caused by chronic hypersecretion of ACTH by pituitary adenoma (corticotropinoma). Surgical resection is a gold standard for this disease resulting stable remission in about 65-95% of cases. Despite benign nature of corticotropinoma, recurrence rate is still higher (25-35%) even in specialized neurosurgical centers. Modifications in surgical strategy can prolong recurrence-free period.

Consideration triggered by the choice of heterophilic antibody interference detection tests in measuring ACTH for a teenager boy with a rare adrenal disease

BACKGROUND

Plasma ACTH is an important marker for Cushing syndrome; inaccurate measurement of ACTH concentrations due to the serum heterophile antibody may mislead diagnosis by physicians. We describe the case of a teenage boy with a rare adrenal disease who presented falsely increased ACTH concentrations (20.3 pg/ml; Siemens Immulite).

METHODS

Low dose dexamethasone inhibition test showed no inhibition of serum cortisol. While biochemical evidence suggested ACTH-dependent Cushing, the imaging tests suggested otherwise. Hence, further tests for interference identification, including test platform replacement, sample dilution, PEG precipitation, and use of blocking antibodies, were conducted.

RESULTS

The measurements of the same patient sample on three different analytical platforms suggested ACTH concentrations below 5 pg/ml. Serial dilutions of serum samples revealed nonlinearity, PEG recovery resulted in ACTH concentrations dropping to < 5 pg/ml, and interferences in plasma were blocked by a heterophilic blocking reagent (21.2 vs < 5 pg/ml), suggesting that assay interference performed on Siemens Immulite led to false-positive ACTH. Finally, the boy was diagnosed with a rare type of ACTH-independent Cushing syndrome.

CONCLUSIONS

The inaccurate evaluation of ACTH misled the physicians, increasing treatment time and diagnostic testing. Thus, an anti-interference workflow should be established between physicians and laboratories to avoid such cases in the future.

Postoperative management of patients with pituitary tumors submitted to pituitary surgery. Experience of a Spanish Pituitary Tumor Center of Excellence

There is a lack of evidence on timing, frequency, and duration of postoperative endocrine, radiologic, and ophthalmologic assessments that should be performed after pituitary surgery (PS). However, it is known that careful optimization of treatment and follow-up strategies as well as a multidisciplinary approach may have a significant impact on long-term outcomes, improving surgical results, minimize complications and facilitate their correct treatment if occurring, and optimize the hormonal, ophthalmological, and radiological reassessment throughout the follow-up. Considering that there are no specific guidelines on the postoperative management of patients with pituitary tumors (PT), we present our protocol for the postoperative management of patients with PT. It has been elaborated by the multidisciplinary team of a Spanish Pituitary Tumor Center of Excellence (PTCE) that includes at least one neurosurgeon, ENT, neuroradiologist, neuro-ophthalmologist, endocrine pathologist and endocrinologist specialized in pituitary diseases. We elaborated this guideline with the aim of sharing our experience with other centers involved in the management of PT thereby facilitating the postoperative management of patients submitted to PS.

Evaluation of plasma ACTH stability using the Roche Elecsys immunoassay

BACKGROUND

Adrenocorticotropic hormone (ACTH) has been reported to be labile in blood due to proteolytic degradation and stringent procedures are followed to prevent in vitro degradation after sample collection.

OBJECTIVE

The purpose of this study was to examine the effect of time and temperature before and after separation of plasma from cells in the quantitation of plasma ACTH.

METHODS

Our current protocol includes sample collection in a pre-chilled tube, transport on ice and immediate centrifugation at 4 °C. These reference conditions were compared against sample processing in tubes and centrifuge set at room-temperature; using delayed centrifugation at 4 °C. ACTH stability was evaluated at ambient and refrigerated temperatures after collection and plasma separation using the reference protocol. Plasma samples were analyzed using the Roche Elecsys ACTH immunoassay.

RESULTS

Quantification of ACTH was not impacted by the use of non-chilled tubes and centrifuge and up to a 4 h delay in separation of plasma from cells. Average percent differences in plasma ACTH concentration from time 0 was <10% up to 12 h at ambient temperature. Refrigeration of plasma did not preserve ACTH stability at 12 h and longer storage resulted in significant ACTH degradation at both ambient and refrigerated temperatures.

CONCLUSIONS

As supported by these data, previously recommended strict specimen collection and processing requirements are not necessary for measuring ACTH with the Roche Elecsys immunoassay.

Fructose-induced inflammation and increased cortisol: A new mechanism for how sugar induces visceral adiposity

Traditionally, the leading hypothesis regarding the development of obesity involves caloric imbalance, whereby the amount of calories consumed exceeds the amount of calories burned which causes obesity. Another hypothesis for why we get fat has surfaced in the last decade which is the idea that the overconsumption of added sugars and refined carbohydrates induce insulin resistance and high insulin levels causing obesity. While insulin is a fat-storing hormone, this hypothesis does not explain visceral adiposity, or why certain people are found to have fat stored in and around their organs. We propose a new mechanism for body fattening, particular visceral adiposity. This hypothesis involves the overconsumption of fructose, which leads to inflammation in all cells that metabolize it rapidly. When fructose is metabolized in subcutaneous adipocytes, the subsequent inflammation leads to an increase in intracellular cortisol in order to help squelch the inflammation. Unfortunately, the increase in intracellular cortisol leads to an increased flux of fatty acids out of the subcutaneous adipocytes allowing more substrate for fat storage into visceral fat tissue. Moreover fructose-induced inflammation in the liver also leads to increased intracellular cortisol via an upregulation of 11-B hydroxysteroid dehydrogenase type 1 causing increased fat storage in the liver (i.e., fatty liver). In essence, the fructose-induced inflammatory cortisol response causes "thin on the outside, fat on the inside" (TOFI). Furthermore, fructose in the brain, either from fructose uptake via the blood brain barrier or endogenous formation from glucose via the polyol pathway stimulates an increased release of cortisol causing hepatic gluconeogenesis leading to overall insulin resistance and further body fattening. This review paper will discuss in detail the hypothesis that fructose-induced inflammation and cortisol activation causes visceral adiposity.

[Rare metabolic disorders and urolithiasis]

Numerous metabolic anomalies, which often have no direct pathological relevance when considered individually, are found in all people. In most patients with urinary tract stones, it can be assumed that a specific combination or interaction of these anomalies occurs, thus, resulting in stone formation, but only after individual exogenous risk factors are triggered. Lithogenesis is the result of a cascade of different "events" that are temporally close to one another, but sometimes these events interact strong enough that significant stone growth occurs. Chronic metabolic disorders usually lead to permanently altered urine compositions. The occurrence of physiological urine constituents in nonnormal concentration ratios and/or the nonphysiological excretion of metabolic products can significantly increase the lithogenicity of urine, so that urolithiasis can manifest itself as a clinical symptom. In cases of urolithiasis of unknown origin, a potentially hidden rare metabolic anomaly should always be considered. In addition, if a patient has a known metabolic disease, then this should always be taken into account as a risk factor for stone formation and attempts should be taken to clarify its influence on urine composition. This also applies to the efficacy of a therapy. A distinct link between a metabolic disease and stone formation is generally rare and will likely remain so despite significant advances regarding differential diagnosis and etiopathology. This article focuses on very rare metabolic causes and/or genetic syndromes which may be associated with urolithiasis. Patients receiving symptomatic stone treatment should receive life-long follow-up care from a urologist because reducing the recurrence rate helps to improve the quality of life of the patients.

Corticotropin-releasing factor overexpression in mice abrogates sex differences in body weight, visceral fat, and food intake response to a fast and alters levels of feeding regulatory hormones

BACKGROUND

Corticotropin-releasing factor overexpressing (CRF-OE) male mice showed an inhibited feeding response to a fast, and lower plasma acyl ghrelin and Fos expression in the arcuate nucleus compared to wild-type (WT) mice. We investigated whether hormones and hypothalamic feeding signals are impaired in CRF-OE mice and the influence of sex.

METHODS

Male and female CRF-OE mice and WT littermates (4-6 months old) fed ad libitum or overnight fasted were assessed for body, adrenal glands and perigonadal fat weights, food intake, plasma hormones, blood glucose, and mRNA hypothalamic signals.

RESULTS

Under fed conditions, compared to WT, CRF-OE mice have increased adrenal glands and perigonadal fat weight, plasma corticosterone, leptin and insulin, and hypothalamic leptin receptor and decreased plasma acyl ghrelin. Compared to male, female WT mice have lower body and perigonadal fat and plasma leptin but higher adrenal glands weights. CRF-OE mice lost these sex differences except for the adrenals. Male CRF-OE and WT mice did not differ in hypothalamic expression of neuropeptide Y (NPY) and proopiomelanocortin (POMC), while female CRF-OE compared to female WT and male CRF-OE had higher NPY mRNA levels. After fasting, female WT mice lost more body weight and ate more food than male WT, while CRF-OE mice had reduced body weight loss and inhibited food intake without sex difference. In male WT mice, fasting reduced plasma insulin and leptin and increased acyl ghrelin and corticosterone while female WT showed only a rise in corticosterone. In CRF-OE mice, fasting reduced insulin while leptin, acyl ghrelin and corticosterone were unchanged with no sex difference. Fasting blood glucose was higher in CRF-OE with female > male. In WT mice, fasting increased hypothalamic NPY expression in both sexes and decreased POMC only in males, while in CRF-OE mice, NPY did not change, and POMC decreased in males and increased in females.

CONCLUSIONS

These data indicate that CRF-OE mice have abnormal basal and fasting circulating hormones and hypothalamic feeding-related signals. CRF-OE also abolishes the sex difference in body weight, abdominal fat, and fasting-induced feeding and changes in plasma levels of leptin and acyl ghrelin.

Analysis of volumetric response of pituitary adenomas receiving adjuvant CyberKnife stereotactic radiosurgery with the application of an exponential fitting model

Tumor control rates of pituitary adenomas (PAs) receiving adjuvant CyberKnife stereotactic radiosurgery (CK SRS) are high. However, there is currently no uniform way to estimate the time course of the disease. The aim of this study was to analyze the volumetric responses of PAs after CK SRS and investigate the application of an exponential decay model in calculating an accurate time course and estimation of the eventual outcome.A retrospective review of 34 patients with PAs who received adjuvant CK SRS between 2006 and 2013 was performed. Tumor volume was calculated using the planimetric method. The percent change in tumor volume and tumor volume rate of change were compared at median 4-, 10-, 20-, and 36-month intervals. Tumor responses were classified as: progression for >15% volume increase, regression for ≤15% decrease, and stabilization for ±15% of the baseline volume at the time of last follow-up. For each patient, the volumetric change versus time was fitted with an exponential model.The overall tumor control rate was 94.1% in the 36-month (range 18-87 months) follow-up period (mean volume change of -43.3%). Volume regression (mean decrease of -50.5%) was demonstrated in 27 (79%) patients, tumor stabilization (mean change of -3.7%) in 5 (15%) patients, and tumor progression (mean increase of 28.1%) in 2 (6%) patients (P = 0.001). Tumors that eventually regressed or stabilized had a temporary volume increase of 1.07% and 41.5% at 4 months after CK SRS, respectively (P = 0.017). The tumor volume estimated using the exponential fitting equation demonstrated high positive correlation with the actual volume calculated by magnetic resonance imaging (MRI) as tested by Pearson correlation coefficient (0.9).Transient progression of PAs post-CK SRS was seen in 62.5% of the patients receiving CK SRS, and it was not predictive of eventual volume regression or progression. A three-point exponential model is of potential predictive value according to relative distribution. An exponential decay model can be used to calculate the time course of tumors that are ultimately controlled.

Adrenalectomy for Cushing's syndrome: do's and don'ts

Aim. To present specific aspects of adrenalectomy for Cushing’s syndrome (CS) by introducing well established aspects (“do’s”) and less known aspects (“don’ts”).

Material and Method. This is a narrative review.

Results. The “do’s” for laparoscopic adrenalectomy (LA) are the following: it represents the “gold standard” for secretor and non-secretor adrenal tumors and the first line therapy for CS with an improvement of cardio-metabolic co-morbidities; the success rate depending on the adequate patients’ selection and the surgeon’s skills. The “don’ts” are large (>6-8 centimeters), locally invasive, malignant tumors requiring open adrenalectomy (OA). Robotic adrenalectomy is a new alternative for LA, with similar safety and conversion rate and lower pain drugs use. The “don’ts” are the following: lack of randomized controlled studies including oncologic outcome, different availability at surgical centers. Related to the sub-types of CS, the “do’s” are the following: adrenal adenomas which are cured by LA, while adrenocortical carcinoma (ACC) requires adrenalectomy as first line therapy and adjuvant mitotane therapy; synchronous bilateral adrenalectomy (SBA) is useful for Cushing’s disease (only cases refractory to pituitary targeted therapy), for ectopic Cushing’s syndrome (cases with unknown or inoperable primary site), and for bilateral cortisol producing adenomas. The less established aspects are the following: criteria of skilled surgeon to approach ACC; the timing of surgery in subclinical CS; the need for adrenal vein catheterization (which is not available in many centers) to avoid unnecessary SBA.

Conclusion. Adrenalectomy for CS is a dynamic domain; LA overstepped the former OA area. The future will improve the knowledge related to RA while the cutting edge is represented by a specific frame of intervention in SCS, children and pregnant women.

Abbreviations: ACC = adrenocortical carcinoma, ACTH = Adrenocorticotropic Hormone, CD = Cushing’s disease, CS = Cushing’s syndrome, ECS = Ectopic Cushing’s syndrome, LA = laparoscopic adrenalectomy, OA = open adrenalectomy, PA = partial adrenalectomy, RA = robotic adrenalectomy, SCS = subclinical Cushing’ syndrome

Recommendations of the Neuroendocrinology Department of the Brazilian Society of Endocrinology and Metabolism for the diagnosis of Cushing's disease in Brazil

Although it is a rare condition, the accurate diagnosis and treatment of Cushing's disease is important due to its higher morbidity and mortality compared to the general population, which is attributed to cardiovascular diseases, diabetes mellitus and infections. Screening for hypercortisolism is recommended for patients who present multiple and progressive clinical signs and symptoms, especially those who are considered to be more specific to Cushing's syndrome, abnormal findings relative to age (e.g., spinal osteoporosis and high blood pressure in young patients), weight gain associated with reduced growth rate in the pediatric population and for those with adrenal incidentalomas. Routine screening is not recommended for other groups of patients, such as those with obesity or diabetes mellitus. Magnetic resonance imaging (MRI) of the pituitary, the corticotropin-releasing hormone (CRH) test and the high-dose dexamethasone suppression test are the main tests for the differential diagnosis of ACTH-dependent Cushing's syndrome. Bilateral and simultaneous petrosal sinus sampling is the gold standard method and is performed when the triad of initial tests is inconclusive, doubtful or conflicting. The aim of this article is to provide information on the early detection and establishment of a proper diagnosis of Cushing's disease, recommending follow-up of these patients at experienced referral centers. Arch Endocrinol Metab. 2016;60(3):267-86.

The Treatment of Cushing's Disease

Cushing's disease (CD), or pituitary-dependent Cushing's syndrome, is a severe endocrine disease caused by a corticotroph pituitary tumor and associated with increased morbidity and mortality. The first-line treatment for CD is pituitary surgery, which is followed by disease remission in around 78% and relapse in around 13% of patients during the 10-year period after surgery, so that nearly one third of patients experience in the long-term a failure of surgery and require an additional second-line treatment. Patients with persistent or recurrent CD require additional treatments, including pituitary radiotherapy, adrenal surgery, and/or medical therapy. Pituitary radiotherapy is effective in controlling cortisol excess in a large percentage of patients, but it is associated with a considerable risk of hypopituitarism. Adrenal surgery is followed by a rapid and definitive control of cortisol excess in nearly all patients, but it induces adrenal insufficiency. Medical therapy has recently acquired a more important role compared to the past, due to the recent employment of novel compounds able to control cortisol secretion or action. Currently, medical therapy is used as a presurgical treatment, particularly for severe disease; or as postsurgical treatment, in cases of failure or incomplete surgical tumor resection; or as bridging therapy before, during, and after radiotherapy while waiting for disease control; or, in selected cases, as primary therapy, mainly when surgery is not an option. The adrenal-directed drug ketoconazole is the most commonly used drug, mainly because of its rapid action, whereas the glucocorticoid receptor antagonist, mifepristone, is highly effective in controlling clinical comorbidities, mainly glucose intolerance, thus being a useful treatment for CD when it is associated with diabetes mellitus. Pituitary-directed drugs have the advantage of acting at the site responsible for CD, the pituitary tumor. Among this group of drugs, the dopamine agonist cabergoline and the somatostatin analog pasireotide result in disease remission in a consistent subgroup of patients with CD. Recently, pasireotide has been approved for the treatment of CD when surgery has failed or when surgery is not an option, and mifepristone has been approved for the treatment of Cushing's syndrome when associated with impairment of glucose metabolism in case of the lack of a surgical indication. Recent experience suggests that the combination of different drugs may be able to control cortisol excess in a great majority of patients with CD.

Mifepristone: is there a place in the treatment of Cushing's disease?

The purpose was to review the use of mifepristone in the treatment of Cushing's syndrome (CS) in the context of other recently published studies. We review the use of mifepristone, as published in the recent Study of the Efficacy and Safety of Mifepristone in the Treatment of Endogenous Cushing's Syndrome (SEISMIC). We also review the multiple case reports and case series of mifepristone use in CS. A review of other medications used in the treatment of Cushing's disease (CD), including pasireotide and cabergoline also provides context for the discussion of the role of mifepristone in the treatment of CD. The results show that the treatment of CD has been primarily surgical with medical therapy reserved for adjuvant therapy when primary treatment fails or other therapies require time for optimal efficacy. Two recent large prospective studies, using pasireotide and mifepristone provide new clinical insights to the medical treatment of CD in particular. Mifepristone has been used to treat excessive cortisol production by blocking the action of cortisol at the level of the glucocorticoid receptor. Until recently, the majority of clinical experience with mifepristone on the treatment of excess cortisol was derived from case reports and small case series. Based on the SEISMIC study, mifepristone was FDA approved for hyperglycemia associated with CS. In conclusion the role of mifepristone in the treatment of CD remains one of adjuvant therapy. Its place among other choices for medical therapy has yet to be firmly established and an evidenced-based approach toward the use of novel medications in the treatment of CD has not been made. Selection of medication depends on drug approval and availability in individual countries and requires cautious assessment of potential adverse effects, consideration of patient comorbidities, and efficacy.

Practical guide to supportive care of patients with functional neuroendocrine tumors

Supportive care of patients with functional neuroendocrine tumors (NETs) has evolved to include the use of multiple targeted agents to control paraneoplastic states and newer surgical and interventional radiologic techniques to reduce tumor bulk. Challenges encountered by the clinician are the recognition of specific symptom complexes, selecting the relevant laboratory tests and radiologic/scintigraphic scans, and the timing of intervention(s). Individual variables such as the severity of symptoms in the context of primary and metastatic disease sites, tumor bulk, comorbidities, and previous treatment are factors determining the prioritization of specific treatment regimens for patients with functional NETs. Symptoms such as flushing, secretory diarrhea, hypercalcemia, hyper /hypoglycemia, hypercortisolism, and peptic ulcers should improve with decreasing the elevated amino acid and/or peptide levels produced by NETs. These paraneoplastic symptoms may be accompanied by complaints related to tumor burden such as fatigue, pain, early satiety, anorexia, weight loss, night sweats, and/or symptoms secondary to adverse drug effects such as mucositis, dysgeusia, diarrhea, rash, hypertension, and myelosuppression. Developing a comprehensive continuum of care plan early in disease management assists in controlling the presenting signs and symptoms, and in minimizing disease- and/or treatment-related side effects. This guide serves as a framework to manage the signs and symptoms of metastatic functional neuroendocrine tumors.

The burden of Cushing's disease: clinical and health-related quality of life aspects

OBJECTIVE

Cushing's disease (CD) is a rare endocrine disorder characterized by excess secretion of ACTH due to a pituitary adenoma. Current treatment options are limited and may pose additional risks. A literature review was conducted to assess the holistic burden of CD.

DESIGN

Studies published in English were evaluated to address questions regarding the epidemiology of CD, time to diagnosis, health-related quality of life (HRQoL), treatment outcomes, mortality, prevalence of comorbidities at diagnosis, and reversibility of comorbidities following the treatment.

METHODS

a two-stage literature search was performed in Medline, EMBASE, and Science Citation Index, using keywords related to the epidemiology, treatment, and outcomes of CD: i) articles published from 2000 to 2012 were identified and ii) an additional hand search (all years) was conducted on the basis of bibliography of identified articles.

RESULTS

At the time of diagnosis, 58-85% of patients have hypertension, 32-41% are obese, 20-47% have diabetes mellitus, 50-81% have major depression, 31-50% have osteoporosis, and 38-71% have dyslipidemia. Remission rates following transsphenoidal surgery (TSS) are high when performed by expert pituitary surgeons (rates of 65-90%), but the potential for relapse remains (rates of 5-36%). Although some complications can be partially reversed, time to reversal can take years. The HRQoL of patients with CD also remains severely compromised after remission.

CONCLUSIONS

These findings highlight the significant burden associated with CD. As current treatment options may not fully reverse the burden of chronic hypercortisolism, there is a need for both improved diagnostic tools to reduce the time to diagnosis and effective therapy, particularly a targeted medical therapy.

Emodin, an 11β-hydroxysteroid dehydrogenase type 1 inhibitor, regulates adipocyte function in vitro and exerts anti-diabetic effect in ob/ob mice

AIM

Emodin (1,3,8-trihydroxy-6-methylanthraquinone) is a potent and selective inhibitor of 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) with the ability to ameliorate metabolic disorders in diet-induced obese mice. In the present study, we investigated the effects of emodin on adipocyte function and the underlying mechanisms in vitro, and its anti-diabetic effects in ob/ob mice.

METHODS

3T3-L1 adipocytes were used for in vitro studies. 11β-HSD1A activity was evaluated with a scintillation proximity assay. The adipogenesis, glucose uptake, lipolysis and adiponectin secretion were investigated in 3T3-L1 adipocytes treated with emodin in the presence of active (corticosterone) or inactive glucocorticoid (11-dehydrocorticosterone). For in vivo studies, ob/ob mice were administered emodin (25 and 50 mg·kg⁻¹·d⁻¹, ip) for 26 d. On the last day of administration, the serum was collected and the mesenteric and perirenal fat were dissected for analyses.

RESULTS

Emodin inhibited the 11β-HSD1 activity in 3T3-L1 adipocytes in concentration- and time-dependent manners (the IC₅₀ values were 7.237 and 4.204 μmol/L, respectively, after 1 and 24 h treatment. In 3T3-L1 adipocytes, emodin (30 μmol/L) suppressed 11-dehydrocorticosterone-induced adipogenesis without affecting corticosterone-induced adipogenesis; emodin (3 μmol/L) reduced 11-dehydrocorticosterone-stimulated lipolysis, but had no effect on corticosterone-induced lipolysis. Moreover, emodin (3 μmol/L) partly reversed the impaired insulin-stimulated glucose uptake and adiponectin secretion induced by 11-dehydrocorticosterone but not those induced by corticosterone. In ob/ob mice, long-term emodin administration decreased 11β-HSD1 activity in mesenteric adipose tissues, lowered non-fasting and fasting blood glucose levels, and improved glucose tolerance.

CONCLUSION

Emodin improves the inactive glucocorticoid-induced adipose tissue dysfunction by selective inhibition on 11β-HSD1 in adipocyte in vitro and improves glycemic control in ob/ob mice.

Emodin, a natural product, selectively inhibits 11beta-hydroxysteroid dehydrogenase type 1 and ameliorates metabolic disorder in diet-induced obese mice

BACKGROUND AND PURPOSE

11beta-Hydroxysteroid dehydrogenase type 1 (11beta-HSD1) is an attractive therapeutic target of type 2 diabetes and metabolic syndrome. Emodin, a natural product and active ingredient of various Chinese herbs, has been demonstrated to possess multiple biological activities. Here, we investigated the effects of emodin on 11beta-HSD1 and its ability to ameliorate metabolic disorders in diet-induced obese (DIO) mice.

EXPERIMENTAL APPROACH

Scintillation proximity assay was performed to evaluate inhibition of emodin against recombinant human and mouse 11beta-HSDs. The ability of emodin to inhibit prednisone- or dexamethasone-induced insulin resistance was investigated in C57BL/6J mice and its effect on metabolic abnormalities was observed in DIO mice.

KEY RESULTS

Emodin is a potent and selective 11beta-HSD1 inhibitor with the IC(50) of 186 and 86 nM for human and mouse 11beta-HSD1, respectively. Single oral administration of emodin inhibited 11beta-HSD1 activity of liver and fat significantly in mice. Emodin reversed prednisone-induced insulin resistance in mice, whereas it did not affect dexamethasone-induced insulin resistance, which confirmed its inhibitory effect on 11beta-HSD1 in vivo. In DIO mice, oral administration of emodin improved insulin sensitivity and lipid metabolism, and lowered blood glucose and hepatic PEPCK, and glucose-6-phosphatase mRNA.

CONCLUSIONS AND IMPLICATIONS

This study demonstrated a new role for emodin as a potent and selective inhibitor of 11beta-HSD1 and its beneficial effects on metabolic disorders in DIO mice. This highlights the potential value of analogues of emodin as a new class of compounds for the treatment of metabolic syndrome or type 2 diabetes.

Emodin, a natural product, selectively inhibits 11beta-hydroxysteroid dehydrogenase type 1 and ameliorates metabolic disorder in diet-induced obese mice

BACKGROUND AND PURPOSE

11beta-Hydroxysteroid dehydrogenase type 1 (11beta-HSD1) is an attractive therapeutic target of type 2 diabetes and metabolic syndrome. Emodin, a natural product and active ingredient of various Chinese herbs, has been demonstrated to possess multiple biological activities. Here, we investigated the effects of emodin on 11beta-HSD1 and its ability to ameliorate metabolic disorders in diet-induced obese (DIO) mice.

EXPERIMENTAL APPROACH

Scintillation proximity assay was performed to evaluate inhibition of emodin against recombinant human and mouse 11beta-HSDs. The ability of emodin to inhibit prednisone- or dexamethasone-induced insulin resistance was investigated in C57BL/6J mice and its effect on metabolic abnormalities was observed in DIO mice.

KEY RESULTS

Emodin is a potent and selective 11beta-HSD1 inhibitor with the IC(50) of 186 and 86 nM for human and mouse 11beta-HSD1, respectively. Single oral administration of emodin inhibited 11beta-HSD1 activity of liver and fat significantly in mice. Emodin reversed prednisone-induced insulin resistance in mice, whereas it did not affect dexamethasone-induced insulin resistance, which confirmed its inhibitory effect on 11beta-HSD1 in vivo. In DIO mice, oral administration of emodin improved insulin sensitivity and lipid metabolism, and lowered blood glucose and hepatic PEPCK, and glucose-6-phosphatase mRNA.

CONCLUSIONS AND IMPLICATIONS

This study demonstrated a new role for emodin as a potent and selective inhibitor of 11beta-HSD1 and its beneficial effects on metabolic disorders in DIO mice. This highlights the potential value of analogues of emodin as a new class of compounds for the treatment of metabolic syndrome or type 2 diabetes.

A new illicit opioid dependence outbreak, evidence for a combination of opioids and steroids

Opioid abuse is common in Iran. In 2005, a new version of locally produced illicit opioid vials, so called Norgesic, appeared in the illicit market, which gained popularity rapidly and led to an improvement of stigmatizing the general appearance of dependent cases. Later, some cases suffered Cushing's-like problems. A prospective case series was designed to evaluate 18 Norgesic-dependent subjects who volunteered for abstinence therapy in a rehabilitation clinic from November 1, 2005, to December 30, 2005. In this study, we aimed to describe the clinical and paraclinical findings in detail and define the potential determinants of this Cushing's syndrome outbreak. History, physical examination, plasma cortisol level, and urine screen tests were used to describe the patients. All subjects were male with a mean (SEM) age of 29.8 +/- 1.6 years. The opioid-dependence period was 8.4 +/-0.9 years. In an average of 4.7 +/- 0.3 months, subjects increased their usage to 5.5 +/- 0.5 vials a day. Patients claimed to gain weight. Striae were seen in 38.9%, previously documented psychological problems in 33.3%, weakness in 27.8%, high systolic blood pressure in 22.2%, moon face in 16.7%, hirsutism in 11.1%, extensive dermal infection in 11.1%, gynecomastia in 5.6%, back pain in 5.6%, insomnia in 5.6%, and lack of potency in 5.6%. Their cortisol level, on average, was 4.8 +/- 1.1 microg/dL. Hepatitis C virus was positive in 22.2%. Urine-screening tests were positive for morphine and negative for buprenorphine. In conclusion, these new vials contain steroids as well as opioids. This combination could be more dangerous than opioids themselves.

A Case of Acute Aortic Dissection Type B Associated with Cushing's Syndrome

We report a case of a 63-year-old man, with a previous history of hypertension and glucose intolerance associated troncular obesity that was emergently admitted to our Institution for evaluation of a severe, constant posterior chest pain which radiated anteriorly and dyspnoea with a suspected diagnosis of acute aortic dissection. A CT scan of thorax and abdomen demonstrated a dissection starting just below left succlavian artery and extending downward to the left renal artery, involving the celiac tripod and superior mesenteric artery. The dissection was classified as Stanford B, De Bakey III. Moreover, CT scan of abdomen revealed incidentally a left adrenal tumor of 25 mm of diameter. An emergent prosthetic graft was placed just below the origin of the left succlavian artery up-to the diaphragmatic hiatus. Furthermore, a diagnostic evaluation of the mass revealed an increase of cortisol production, and a diagnosis of Cushing's syndrome was done and the patient underwent an adrenalectomy via laparotomic approach. We report an association of acute aortic dissection of acute aortic dissection type B associated to Cushing's syndrome.

KEYWORDS

Cushing's syndrome; Adrenocortical adenoma; Aortic dissection type B.

[Pseudo-Cushing states]

Pseudo-Cushing syndromes are a heterogeneous group of disorders, including alcoholism, anorexia nervosa, visceral obesity, and depression, which share many of the clinical and biochemical features of Cushing's syndrome. The mechanisms responsible for the genesis of pseudo-Cushing's syndrome are poorly understood. It has been suggested that hypercortisolism of pseudo-Cushing syndrome may be the result of increased hypothalamic corticotrophin-releasing hormone (CRH) secretion in the context of a hypothalamic-pituitary-adrenal axis that is otherwise normally constituted. The substantial overlap in clinical and biochemical features among several patients with Cushing syndrome and those with pseudo-Cushing syndromes can make the differential diagnosis difficult. Distinguishing between pseudo-Cushing's syndrome and true Cushing's syndrome is critical for preventing the unnecessary and potentially harmful treatment of such patients. This brief review summarizes the main pathophysiological events of pseudo-Cushing syndromes and provides a useful strategy for differential diagnosis.

[Hormonal axes in obesity: cause or effect?]

Several endocrine changes have been described in the obesity state. The corticotropic axis is hyperresponsive and there is enhancement of hormonal clearance, but cortisol levels are within the normal range. It is important to characterize a pseudo-Cushing in obesity. Leptin seems to be a permissive hormone for the beginning of puberty. In adults, gonadotropines are normal, and hyperandrogenism and hyperestrogenism are found. In women, insulin resistance has a central role in polycystic ovarian syndrome (POS), which is associated to ovarian hyperandrogenemia. In obese subjects, growth hormone (GH) is generally low and IGF1 is normal. Thyroid function is commonly normal in obese subjects.

Postoperative assessment of the patient after transsphenoidal pituitary surgery

While most transsphenoidal pituitary surgery is accomplished without complication, monitoring is required postoperatively for a set of disorders that are specific to this surgery. Postoperative assessments are tailored to the early and later postoperative periods. In the early period, which spans the first few weeks after surgery, both monitoring of anterior and posterior pituitary function and managing neurosurgical issues are the focus of care. Potential disruption of pituitary-adrenal function is covered with perioperative glucocorticoids. Various strategies exist for ensuring the integrity of this axis, but typically this is done by measuring a morning cortisol on the 2nd or 3rd postoperative days. Patients with levels <10 microg/l should continue therapy with reassessment in the later postoperative period. Monitoring for water imbalances, which are due to deficiency or excess of ADH (DI or SIADH, respectively), is accomplished by continuous accounting of fluid intake, urine output and specific gravities coupled with daily serum electrolyte measurements. DI is characterized by excess volumes of inappropriately dilute urine, which can lead to hypernatremia. Most patients maintain adequate fluid intake and euvolemia, but desmopressin therapy is required for some. SIADH, which peaks in incidence on 7th postoperative day, presents with hyponatremia that can be severe and symptomatic. Management consists of fluid restriction. Neurosurgical monitoring is primarily for disturbances in vision or neurological function, and although uncommon, for CSF leak and infections such as meningitis. In the later postoperative period, the adrenal, thyroid and gonadal axes are assessed. New persistent hypopituitarism is rare when transsphenoidal surgery is performed by an experienced surgeon. Various strategies are available for assessing each axis and for providing replacement therapy in patients with deficiencies. Long term monitoring with assessments of visual, neurological and pituitary function coupled with pituitary imaging is necessary for all patients who have undergone surgery, irrespective of the hormone status of their tumors.

Antisense inhibition of 11betahydroxysteroid dehydrogenase type 1 improves diabetes in a novel cortisone-induced diabetic KK mouse model

The inhibition of 11betahydroxysteroid dehydrogenase 1 (11betaHSD1), an enzyme that catalyzes the conversion of inactive cortisone to active cortisol, is an attractive target to treat diabetes by suppressing hepatic gluconeogenesis. To test this hypothesis, we developed a novel glucocorticoid-induced diabetic KK mouse model and used 11betaHSD1 antisense oligonucleotide (ASO) as an inhibitory tool. KK mice were treated with 25 or 50mg/kg/day of 11betaHSD1 ASO for 28 days. On day 25, cortisone pellets were surgically implanted to induce diabetes. In the ASO-treated mice, plasma blood glucose levels were significantly reduced by up to 54%. In parallel, cortisol and other diabetes endpoints were also significantly reduced. Hepatic 11betaHSD1 mRNA was suppressed by up to 84% with a concomitant respective decrease of up to 49% in the expression of PEPCK. The results suggest that inhibition of 11betaHSD1 activity reduces the availability of cortisol to activate the glucocorticoid receptor, down regulates gluconeogenesis and thus reduces plasma glucose levels in cortisone-induced diabetic KK mice.

Molecular identification of the human melanocortin-2 receptor responsible for ligand binding and signaling

The melanocortin-2 receptor (MC2R), also known as the adrenocorticotropic hormone (ACTH) receptor, plays an important role in regulating and maintaining adrenocortical function, specifically steroidogenesis. Mutations of the human MC2R (hMC2R) gene have also been identified in humans with familial glucocorticoid deficiency; however, the molecular basis responsible for hMC2R ligand binding and signaling remains unclear. In this study, both truncated ACTH peptides and site-directed mutagenesis studies were used to determine molecular mechanisms of hMC2R binding ACTH and signaling. Our results indicate that ACTH1-16 is the minimal peptide required for hMC2R binding and signaling. Mutations of common melanocortin receptor family amino acid residues E80 in transmembrane domain 2 (TM2), D107 in TM3, F178 in TM4, F235 and H238 in TM6, and F258 in TM7 significantly reduced ACTH-binding affinity and signaling. Furthermore, mutations of unique amino acids D104 and F108 in TM3 and F168 and F178 in TM4 significantly decreased ACTH binding and signaling. In conclusion, our results suggest that the residues in TM2, TM3, and TM6 of hMC2R share similar binding sites with other MCRs but the residues identified in TM4 and TM7 of hMC2R are unique and required for ACTH selectivity. Our study suggests that hMC2R may have a broad binding pocket in which both conserved and unique amino acid residues are required, which may be the reason why alpha-MSH was not able to bind hMC2R.

Cushing's syndrome patient who exhibited congestive heart failure

Cushing's Syndrome (CS) may sometimes lead to dilated cardiomyopathy, even though this condition can be partially or completely reversed after treatment. In this article we report the case of a 28-yr-old woman with CS secondary to adrenal adenoma who exhibited congestive heart failure as an initial symptom. Two weeks before being admitted to our hospital, the patient started complaining of shortness of breath, orthopnea, paroxysmal nocturnal dyspnea and generalized edema. A physical examination did not reveal signs of hypercortisolism. Chest auscultation revealed bilateral diffused crepitation; blood pressure was 180/120 mmHg with heart rate of 90 beats/min. A chest X-ray showed a cardiac shade enlargement due to congestive heart failure. Transthoracic echocardiography demonstrated a dilated left ventricle and an impaired left ventricular systolic function. The patient's urinary cortisol excretion was elevated and circadian rhythm of cortisol was absent. ACTH level was low. In addition, plasma cortisol failed to decrease after administration of dexamethasone. An abdominal magnetic resonance imaging scan showed a 7-cm right adrenal mass. The patient was administered oxygen, spironolactone, ACE-inhibitor and the signs and symptoms of heart failure gradually improved. A laparoscopic right adrenalectomy was performed and pathological examination of the gland showed a benign adrenocortical adenoma. After the adrenalectomy the patient was started on hydrocortisone therapy and 5 months later the wall thickness of the left ventricle was within normal range and the patient's blood pressure was 130/80 mmHg. In conclusion we report the case of heart failure as the main clinical symptom in CS secondary to adrenal adenoma.

Adrenocorticotropin-secreting pancreatoblastoma

We present a 3-year-old child with Cushing's syndrome due to an ACTH-secreting metastatic pancreatoblastoma. This malignancy is a rare cause of Cushing's syndrome, particularly at pediatric age. We describe her course including the use of ketoconazole to alleviate hypercortisolemia.

Pharmacologic Management of Cushing Syndrome

The successful treatment of Cushing syndrome depends on specific therapy directed against the etiology of hypercortisolism. In addition to surgical procedures, various drugs have been employed in the management of this difficult disease. Compounds with neuromodulatory properties have been effective in only a limited number of cases of hypothalamic-pituitary-dependent Cushing disease, the most common form of Cushing syndrome. These agents include serotonin antagonists (cyproheptadine, ketanserin, ritanserin), dopamine agonists (bromocriptine, cabergoline), GABA agonists (valproic acid [sodium valproate]), and somatostatin analogs (octreotide). Interesting new avenues at the pituitary level involve the potential use of thiazolidinedione compounds, such as rosiglitazone, and of retinoic acid, which are ligands of different nuclear hormone receptors involved in hypothalamic-pituitary regulation. The most exciting news, however, in the pharmacologic approach to Cushing syndrome refers to the adrenal corticotropin (adrenocorticotropic hormone; ACTH)-independent forms, in which aberrant adrenal receptors, through the binding of their respective ligands, could lead to chronic cortisol overproduction. They include receptors for gastric inhibitory peptide (GIP), beta-adrenergic agonists, luteinizing hormone (LH)/human chorionic gonadotropin, serotonin (5-HT(4) receptor), vasopressin (V(1) receptor), and angiotensin II (AT(1) receptor). In GIP-dependent Cushing syndrome, the most frequent subtype of ACTH-independent macronodular adrenal hyperplasia associated with the presence of aberrant adrenocortical hormone receptors described so far, octreotide administration before each meal showed clinical efficacy only in the first few months, probably because of somatostatin receptor downregulation in GIP-secreting cells. Long-term medical treatments with propranolol and the gonadotropin-releasing hormone analog leuprorelin (leuprolide acetate) were effective in patients with catecholamine-dependent and LH-dependent Cushing syndrome, respectively. The oral vasopressin V(1) receptor antagonist OPC-21268 and the angiotensin II (AT(1)) receptor antagonist candesartan cilexetil were also able to decrease cortisol levels during the few days of administration of the drugs in patients with specific receptor abnormalities. These adrenal forms of Cushing syndrome are rare, and clinical data are scarce. Moreover, the real clinical significance of aberrant hormone receptors is still under investigation, as is the possibility of avoiding surgery by pharmacologic manipulation. Patients in whom these intriguing syndromes are suspected require detailed investigation protocols, which should be carried out in specialized centers. While awaiting further developments, the use of traditional medical treatment at the adrenal level with adrenal steroid inhibitors is still valuable in several instances.