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BACKGROUND: Immunotherapy with immune checkpoint inhibitors is a new frontier for cancer treatment. On the safety profile, this drugs class is associated with a new spectrum of side effects, the so-called immune-related adverse events that can potentially affect any organs, mainly endocrine glands. Scant data are available to inform the appropriate strategy of their management and treatment. CASE PRESENTATION: A 74-years old man with a squamous non-small cell lung cancer on nivolumab was hospitalized for fatigue, nausea, vomiting and severe hyponatremia. Biochemical tests were significant for hypotonic hyponatremia with a high urine sodium concentration. Endocrine tests showed overt primary hypothyroidism and low serum cortisol and aldosterone levels associated with an elevated circulating level of adrenocorticotrophic hormone. Adrenal antibody screening and the search of adrenal lesion on CT abdomen were negative. Thus, a nivolumab-induced primary adrenal insufficiency was diagnosed. Nivolumab withdrawal and replacement treatment with glucocorticoid and mineralocorticoid allowed clinical and biochemical recovery. CONCLUSION: Physicians need to be aware of potential immune-related adverse events in all patients treated with an immune checkpoint inhibitor. Their timely recognition is essential to carry out the proper treatment.
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Enfermedad de Addison , Carcinoma de Pulmón de Células no Pequeñas , Hiponatremia , Neoplasias Pulmonares , Enfermedad de Addison/inducido químicamente , Enfermedad de Addison/diagnóstico , Anciano , Carcinoma de Pulmón de Células no Pequeñas/inducido químicamente , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Humanos , Hiponatremia/inducido químicamente , Hiponatremia/diagnóstico , Neoplasias Pulmonares/inducido químicamente , Neoplasias Pulmonares/tratamiento farmacológico , Masculino , Nivolumab/efectos adversosRESUMEN
Approximately 60% of acromegaly patients are not adequately controlled by first-generation somatostatin receptor ligands. This multicenter retrospective study aimed to identify the most relevant biomarkers specific for the Italian acromegaly population. Resistant patients were enrolled consecutively based on time of neurosurgery, while responders were collected in a 1:2 ratio. Clinical characteristics and T2-intensity on MRI scans at diagnosis were retrospectively re-evaluated. Histological analyses of CAM5.2 granulation patterns and SSTR2 expression were centrally performed. Sixty-three resistant patients and thirty-three responders were enrolled. A low-grade SSTR2 expression was the most relevant predictor of resistance identified (OR 4.58, p = 0.013), even considering CAM5.2 immunohistochemistry (OR 2.65, p = 0.047). T2-iso/hyperintense pattern on MRI was also associated with a 3.3-fold greater probability of poor response to medical treatment (p = 0.027), as well as a young age at diagnosis (OR 0.96, p = 0.035). In those patients treated only after neurosurgery due to persistent GH-hypersecretion (51, 53.1%) the absence of any appreciable adenomatous remnant on postoperative MRI was associated with a negligible risk of resistance (OR 0.04, p = 0.003). In the Italian acromegaly population, a low-grade SSTR2 expression seems to be the most relevant predictor of resistance to first-generation somatostatin receptor ligands, followed by a SG/intermediate cytokeratin pattern and a T2-iso/hyperintense MRI signal.
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Coronaviruses are a big family of viruses that can infect mammalians and birds. In humans they mainly cause respiratory tract infections, with a large spectrum of severity, from mild, self-limited infections to highly lethal forms as severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV) and Coronavirus Disease 2019 (COVID-19). Scanty data are reported for the involvement of endocrine glands in human coronaviruses, in particular SARS-CoV-2. In this review, we summarize endocrinological involvement in human coronaviruses, including data on animal coronaviruses. Avians, ferrets and bovine are affected by specific coronavirus syndromes, with variable involvement of endocrine glands. SARS-CoV and SARS-CoV-2 use angiotensin-converting enzyme 2 (ACE2) as a target receptor, so ACE2 plays a central role in viral transmission and initial organ involvement. Autoptic studies on SARS patients revealed that thyroid, parathyroid, pituitary gland, endocrine pancreas and especially adrenals and testis could be impaired by different mechanisms (direct damage by SARS-CoV, inflammation, vascular derangement and autoimmune reactions) and few clinical studies have evidenced functional endocrine impairment. Only few data are available for COVID-19 and gonads and endocrine pancreas seem to be involved. International endocrinological societies have brought some recommendations for the COVID-19 pandemic, but further studies need to be performed, especially to detect long-term hormonal sequelae.
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COVID-19/metabolismo , Glándulas Endocrinas/metabolismo , Enfermedades del Sistema Endocrino/metabolismo , Coronavirus del Síndrome Respiratorio de Oriente Medio/metabolismo , SARS-CoV-2/metabolismo , Enzima Convertidora de Angiotensina 2/inmunología , Enzima Convertidora de Angiotensina 2/metabolismo , Animales , COVID-19/epidemiología , COVID-19/inmunología , Glándulas Endocrinas/inmunología , Sistema Endocrino/inmunología , Sistema Endocrino/metabolismo , Enfermedades del Sistema Endocrino/epidemiología , Enfermedades del Sistema Endocrino/inmunología , Humanos , Coronavirus del Síndrome Respiratorio de Oriente Medio/inmunología , SARS-CoV-2/inmunologíaAsunto(s)
Neoplasias de las Glándulas Suprarrenales/genética , Neoplasia Endocrina Múltiple Tipo 2a/genética , Feocromocitoma/genética , Proteínas Proto-Oncogénicas c-ret/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Exones , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mutación , Penetrancia , Adulto JovenRESUMEN
The precise diagnosis of thyroid neoplasias will guide surgical management. Primary thyroid paraganglioma has been rarely reported. Data on prevalence, immunohistochemistry (IHC), and molecular genetics in a systematic series of such patients are pending. We performed a multinational population-based study on thyroid paraganglioma and analyzed prevalence, IHC, and molecular genetics. Patients with thyroid paraganglioma were recruited from the European-American-Head-and-Neck-Paraganglioma-Registry. Demographic and clinical data were registered. Histopathology and IHC were re-investigated. All patients with thyroid paraganglioma underwent molecular genetic analyses of the SDHA, SDHB, SDHC, SDHD, SDHAF2, VHL, RET, TMEM127, and MAX genes. Analyses included Sanger sequencing and multiplex ligation-dependent probe amplification (MLPA) for detection of large rearrangements. Of 947 registrants, eight candidates were initially identified. After immunohistochemical analyses of these eight subjects, 5 (0.5%) were confirmed to have thyroid paraganglioma. IHC was positive for chromogranin, synaptophysin, and S-100 and negative for calcitonin in all five thyroid paragangliomas, whereas the three excluded candidate tumors stained positive for pan-cytokeratin, a marker excluding endocrine tumors. Germline variants, probably representing mutations, were found in four of the five confirmed thyroid paraganglioma cases, two each in SDHA and SDHB, whereas the excluded cases had no mutations in the tested genes. Thyroid paraganglioma is a finite entity, which must be differentiated from medullary thyroid carcinoma, because medical, surgical, and genetic management for each is different. Notably, approximately 80% of thyroid paragangliomas are associated with germline variants, with implications for additional tumors and a potential risk for the family. As opposed to sporadic tumors, surgical management and extent of resection are different for heritable tumors, each guided by the precise gene involved.
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Paraganglioma , Neoplasias de la Tiroides , Adulto , Anciano , Calcitonina/metabolismo , Cromogranina A/metabolismo , Proteínas de Unión al ADN/metabolismo , Complejo II de Transporte de Electrones/genética , Femenino , Alemania/epidemiología , Humanos , Queratinas/metabolismo , Masculino , Persona de Mediana Edad , Mutación , Paraganglioma/epidemiología , Paraganglioma/genética , Paraganglioma/patología , Prevalencia , Sistema de Registros , Proteínas S100/metabolismo , Succinato Deshidrogenasa/genética , Sinaptofisina/metabolismo , Neoplasias de la Tiroides/epidemiología , Neoplasias de la Tiroides/genética , Neoplasias de la Tiroides/patología , Factores de TranscripciónRESUMEN
BACKGROUND: The prevention of medullary thyroid cancer in patients with multiple endocrine neoplasia type 2 syndrome has demonstrated the ability of molecular diagnosis and prophylactic surgery to improve patient outcomes. However, the other major neoplasia associated with multiple endocrine neoplasia type 2, phaeochromocytoma, is not as well characterised in terms of occurrence and treatment outcomes. In this study, we aimed to systematically characterise the outcomes of management of phaeochromocytoma associated with multiple endocrine neoplasia type 2. METHODS: This multinational observational retrospective population-based study compiled data on patients with multiple endocrine neoplasia type 2 from 30 academic medical centres across Europe, the Americas, and Asia. Patients were included if they were carriers of germline pathogenic mutations of the RET gene, or were first-degree relatives with histologically proven medullary thyroid cancer and phaeochromocytoma. We gathered clinical information about patients'RET genotype, type of treatment for phaeochromocytoma (ie, unilateral or bilateral operations as adrenalectomy or adrenal-sparing surgery, and as open or endoscopic operations), and postoperative outcomes (adrenal function, malignancy, and death). The type of surgery was decided by each investigator and the timing of surgery was patient driven. The primary aim of our analysis was to compare disease-free survival after either adrenal-sparing surgery or adrenalectomy. FINDINGS: 1210 patients with multiple endocrine neoplasia type 2 were included in our database, 563 of whom had phaeochromocytoma. Treatment was adrenalectomy in 438 (79%) of 552 operated patients, and adrenal-sparing surgery in 114 (21%). Phaeochromocytoma recurrence occurred in four (3%) of 153 of the operated glands after adrenal-sparing surgery after 6-13 years, compared with 11 (2%) of 717 glands operated by adrenalectomy (p=0.57). Postoperative adrenal insufficiency or steroid dependency developed in 292 (86%) of 339 patients with bilateral phaeochromocytoma who underwent surgery. However, 47 (57%) of 82 patients with bilateral phaeochromocytoma who underwent adrenal-sparing surgery did not become steroid dependent. INTERPRETATION: The treatment of multiple endocrine neoplasia type 2-related phaeochromocytoma continues to rely on adrenalectomies with their associated Addisonian-like complications and consequent lifelong dependency on steroids. Adrenal-sparing surgery, a highly successful treatment option in experienced centres, should be the surgical approach of choice to reduce these complications.
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Neoplasias de las Glándulas Suprarrenales/cirugía , Neoplasia Endocrina Múltiple Tipo 2a/complicaciones , Neoplasia Endocrina Múltiple Tipo 2a/cirugía , Feocromocitoma/cirugía , Adolescente , Neoplasias de las Glándulas Suprarrenales/etiología , Neoplasias de las Glándulas Suprarrenales/mortalidad , Adrenalectomía/mortalidad , Adulto , Anciano , Anciano de 80 o más Años , Niño , Supervivencia sin Enfermedad , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Neoplasia Endocrina Múltiple Tipo 2a/mortalidad , Feocromocitoma/etiología , Feocromocitoma/mortalidad , Estudios Retrospectivos , Resultado del Tratamiento , Adulto JovenRESUMEN
Medullary thyroid carcinoma currently accounts for 5-8% of all thyroid cancers. The clinical course of this disease varies from extremely indolent tumors that can go unchanged for years to an extremely aggressive variant that is associated with a high mortality rate. As many as 75% of all medullary thyroid carcinomas are sporadic, with an average age at presentation reported as 60 years, and the remaining 25% are hereditary with an earlier age of presentation, ranging from 20 to 40 years. Germline RET proto-oncogene mutations are the genetic causes of multiple endocrine neoplasia type 2 and a strong genotype-phenotype correlation exists, particularly between a specific RET codon mutation and the (a) age-related onset and (b) thyroid tumor progression, from C-cell hyperplasia to medullary thyroid carcinoma and, ultimately, to nodal metastases. RET mutations predispose an individual to the development of medullary thyroid carcinomas and can also influence the individual response to RET protein receptor-targeted therapies. RET codon 609 point mutations are rare genetic events belonging to the intermediate risk category for the onset of medullary thyroid carcinoma. A large genealogy resulting in a less aggressive form of medullary thyroid carcinoma is associated with the high penetrance of pheochromocytoma and has been reported in the literature. In this short review article, we comment on our previous report of a large multiple endocrine neoplasia type 2A kindred with the same Cys609Ser germline RET mutation in which, conversely, the syndrome was characterized by a slightly aggressive, highly penetrant form of medullary thyroid carcinoma that was associated with low penetrance of pheochromocytoma and primary hyperparathyroidism.
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Carcinoma Medular/genética , Codón/genética , Mutación de Línea Germinal/genética , Neoplasia Endocrina Múltiple Tipo 2a/genética , Proteínas Proto-Oncogénicas c-ret/genética , Neoplasias de la Tiroides/genética , Carcinoma Neuroendocrino , Cisteína/genética , Estudios de Asociación Genética , Humanos , Hiperparatiroidismo/genética , Italia , Linaje , Proto-Oncogenes Mas , Serina/genéticaRESUMEN
Medullary thyroid carcinoma currently accounts for 5-8% of all thyroid cancers. The clinical course of this disease varies from extremely indolent tumors that can go unchanged for years to an extremely aggressive variant that is associated with a high mortality rate. As many as 75% of all medullary thyroid carcinomas are sporadic, with an average age at presentation reported as 60 years, and the remaining 25% are hereditary with an earlier age of presentation, ranging from 20 to 40 years. Germline RET proto-oncogene mutations are the genetic causes of multiple endocrine neoplasia type 2 and a strong genotype-phenotype correlation exists, particularly between a specific RET codon mutation and the (a) age-related onset and (b) thyroid tumor progression, from C-cell hyperplasia to medullary thyroid carcinoma and, ultimately, to nodal metastases. RET mutations predispose an individual to the development of medullary thyroid carcinomas and can also influence the individual response to RET protein receptor-targeted therapies. RET codon 609point mutations are rare genetic events belonging to the intermediate risk category for the onset of medullary thyroid carcinoma. A large genealogy resulting in a less aggressive form of medullary thyroid carcinoma is associated with the high penetrance of pheochromocytoma and has been reported in the literature. In this short review article, we comment on our previous report of a large multiple endocrine neoplasia type 2A kindred with the same Cys609Ser germline RET mutation in which, conversely, the syndrome was characterized by a slightly aggressive, highly penetrant form of medullary thyroid carcinoma that was associated with low penetrance of pheochromocytoma and primary hyperparathyroidism.
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Humanos , Carcinoma Medular/genética , Codón/genética , Mutación de Línea Germinal/genética , /genética , Proteínas Proto-Oncogénicas c-ret/genética , Neoplasias de la Tiroides/genética , Cisteína/genética , Estudios de Asociación Genética , Hiperparatiroidismo/genética , Italia , Linaje , Serina/genéticaRESUMEN
The mineralocorticoid receptor (MR) is essential in the regulation of volemia and blood pressure. Rare mutations in the MR gene cause type 1 pseudohypoaldosteronism and hypertension. In this study we characterized the common MR polymorphism c.-2G>C (rs2070951) in vitro and tested its influence on parameters related to blood pressure regulation and the renin-angiotensin system. In vitro studies showed that the G allele was associated with decreased MR protein levels and reduced transcriptional activation compared with the C allele. Association studies were performed with several outcome variables in 3 independent cohorts: a mild hypertensive group subjected to a salt-sensitivity test, a healthy normotensive group included in a crossover study to receive both a high and low Na/K diet, and a large cohort (The Netherlands Study of Depression and Anxiety), in which blood pressure was measured. Subjects with the GG genotype had significantly higher plasma renin levels both in the mild hypertensive group and in normal volunteers compared with homozygous C carriers. The GG genotype was also correlated with higher plasma aldosterone levels in healthy subjects. In both the mild hypertensive group and The Netherlands Study of Depression and Anxiety cohort the genotype GG was associated with higher systolic blood pressure in males. In conclusion, the G allele of the common functional genetic polymorphism c.-2G>C in the MR gene associates with increased activation of the renin-angiotensin-aldosterone axis and with increased blood pressure, probably related to decreased MR expression.
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Aldosterona/sangre , Presión Sanguínea/genética , Receptores de Mineralocorticoides/genética , Sistema Renina-Angiotensina/genética , Renina/sangre , Adolescente , Adulto , Anciano , Aldosterona/genética , Alelos , Estudios Cruzados , Femenino , Estudios de Asociación Genética , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Renina/genética , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
Primary aldosteronism (PA) is the most common cause of mineralocorticoid hypertension. Different studies using the plasma aldosterone concentration (PAC)-plasma renin activity ratio (ARR ratio) for the screening of patients with hypertension, have shown a marked increase in the detection rate of PA. PA is commonly caused by an adrenal adenoma (APA) or idiopathic bilateral adrenal hyperplasia of the adrenal zona glomerulosa (IHA) and, in rare cases, by the inherited condition of glucocorticoid-remediable aldosteronism (GRA). The early diagnosis of PA is important, not only because the forms caused by adrenal adenoma are surgically curable, but also because correlation between the duration of PA and the development of cardiovascular complications has been reported. Patients with resistant and/or severe hypertension, patients with hypokalemia, those with a family history of hypertension and stroke at an early age, or patients with an adrenal incidentaloma should be screened for PA using the ARR ratio. Suspicion of PA owing to a pathological ratio requires confirmatory testing, including fludrocortisone suppression test, saline infusion and captopril challenge. Adrenal gland imaging is important in subtype differentiation (APA vs IHA), but adrenal venous sampling is the gold standard and should be used when other tests prove inconclusive. Genetic testing has facilitated detection of GRA.
RESUMEN
Endocrine hypertension is a term used for states in which hormone derangements result in clinically significant hypertension. The adrenal glands are the most likely culprits, due either to an excessive production of mineralocorticoids, catecholamines or glucocorticoids. The term 'adrenal incidentaloma' indicates an adrenal mass discovered accidentally during testing or treatment for other clinical conditions unrelated to any suspicion of adrenal disease. In particular, when an adrenal mass is discovered in a hypertensive subject, physicians must check whether the patient has pheochromocytoma, glucocorticoid excess or primary aldosteronism. Although most adrenal masses are non-hypersecretory adenomas, hormone screening can reveal a significant number of cases of clinically unsuspected hormone-secreting adrenal tumors. If the clinical history or physical examination of a patient with unilateral incidentaloma shows signs and symptoms suggestive of glucocorticoid, mineralocorticoid, adrenal sex hormone or catecholamine excess, which is confirmed biochemically, the treatment of choice is often adrenalectomy. In cases where surgery is contraindicated or the lesions are unresectable, medical treatment may be an option.
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Neoplasias de las Glándulas Suprarrenales/diagnóstico , Hipertensión/etiología , Adenoma/complicaciones , Adenoma/diagnóstico , Adenoma/metabolismo , Neoplasias de las Glándulas Suprarrenales/complicaciones , Neoplasias de las Glándulas Suprarrenales/cirugía , Aldosterona/metabolismo , Síndrome de Cushing/complicaciones , Síndrome de Cushing/diagnóstico , Diagnóstico por Imagen , Humanos , Hallazgos Incidentales , Metástasis de la Neoplasia/diagnóstico , Feocromocitoma/complicaciones , Feocromocitoma/diagnósticoRESUMEN
UNLABELLED: Licorice has been considered a medicinal plant for thousands of years. Its most common side effect is hypokalemic hypertension, which is secondary to a block of 11beta-hydroxysteroid dehydrogenase type 2 at the level of the kidney, leading to an enhanced mineralocorticoid effect of cortisol. This effect is due to glycyrrhetinic acid, which is the main constituent of the root, but other components are also present, including isoflavans, which have estrogen-like activity, and are thus involved in the modulation of bone metabolism. We investigated nine healthy women 22-26 years old, in the luteal phase of the cycle. They were given 3.5 g of a commercial preparation of licorice (containing 7.6%, w/w of glycyrrhizic acid) daily for 2 months. Plasma renin activity (PRA), aldosterone, cortisol, serum parathyroid hormone (PTH), 1,25-dihydroxy Vitamin D (1,25OHD), 25-hydroxycholecalciferol (25OHD), estradiol, FHS, LH, alkaline phosphatase (ALP), calcium, phosphate and creatinine, urinary calcium and phosphate and mineralometry were measured. PTH, 25OHD and urinary calcium increased significantly from baseline values after 2 months of therapy, while 1,25OHD and ALP did not change during treatment. All these parameters returned to pretreatment levels 1 month after discontinuation of licorice. PRA and aldosterone were depressed during therapy, while blood pressure and plasma cortisol remained unchanged. CONCLUSIONS: licorice can increase serum PTH and urinary calcium levels from baseline value in healthy women after only 2 months of treatment. The effect of licorice on calcium metabolism is probably influenced by several components of the root, which show aldosterone-like, estrogen-like and antiandrogen activity.
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Glycyrrhiza , Ácido Glicirrínico/farmacología , Hormona Paratiroidea/sangre , Preparaciones de Plantas/farmacología , Adulto , Aldosterona/sangre , Fosfatasa Alcalina/sangre , Antiinflamatorios/análisis , Antiinflamatorios/farmacología , Calcifediol/sangre , Calcitriol/sangre , Calcio/sangre , Calcio/orina , Creatinina/sangre , Estradiol/sangre , Femenino , Glycyrrhiza/química , Ácido Glicirrínico/análisis , Gonadotropinas Hipofisarias/sangre , Humanos , Hidrocortisona/sangre , Fosfatos/sangre , Fosfatos/orina , Preparaciones de Plantas/química , Valores de Referencia , Renina/sangreRESUMEN
To explore the relationship between variation in AGT M235T gene and the development of the polycystic ovary syndrome (PCOS) and its sequelae, in the present study we evaluated AGT polymorphism M235T in women with PCOS and in a control group. Moreover, to detect any relationship between AGT M235T variation and intermediate and quantitative traits relevant to the pathogenesis of cardiovascular disease and PCOS, we looked for genotype-dependent differences within the subjects with PCOS.
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Angiotensinógeno/genética , Síndrome del Ovario Poliquístico/genética , Polimorfismo Genético/genética , Anciano , Anciano de 80 o más Años , Sustitución de Aminoácidos/genética , Distribución de Chi-Cuadrado , Femenino , Genotipo , Humanos , Metionina/genética , Persona de Mediana Edad , Treonina/genéticaRESUMEN
UNLABELLED: Licorice has been considered a medicinal plant for thousands of years. The most common side effect is hypokalemic hypertension, which is secondary to a block of 11beta-hydroxysteroid dehydrogenase type 2 at the level of the kidney, leading to an enhanced mineralocorticoid effect of cortisol. We have investigated the effect of licorice on androgen metabolism in nine healthy women 22-26 years old, in the luteal phase of the cycle. They were given 3.5 g of a commercial preparation of licorice (containing 7.6% W.W. of glycyrrhizic acid) daily for two cycles. They were not on any other treatment. Plasma renin activity, serum adrenal and gonadal androgens, aldosterone, and cortisol were measured by radioimmunoassay. Total serum testosterone decreased from 27.8+/-8.2 to 19.0+/-9.4 in the first month and to 17.5+/-6.4 ng/dL in the second month of therapy (p<0.05). It returned to pre-treatment levels after discontinuation. Androstenedione, 17OH-progesterone, and LH levels did not change significantly during treatment. Plasma renin activity and aldosterone were depressed during therapy, while blood pressure and cortisol remained unchanged. CONCLUSIONS: Licorice can reduce serum testosterone probably due to the block of 17-hydroxysteroid dehydrogenase and 17-20 lyase. Licorice could be considered an adjuvant therapy of hirsutism and polycystic ovary syndrome.
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Glycyrrhiza/metabolismo , Extractos Vegetales/farmacología , Testosterona/antagonistas & inhibidores , Testosterona/sangre , Glándulas Suprarrenales/metabolismo , Adulto , Aldosterona/sangre , Aldosterona/metabolismo , Andrógenos/sangre , Androstenodiona/metabolismo , Femenino , Ácido Glicirrínico/química , Humanos , Hidrocortisona/sangre , Fase Luteínica , Síndrome del Ovario Poliquístico/terapia , Progesterona/metabolismo , Radioinmunoensayo , Renina/sangre , Factores de TiempoRESUMEN
We have investigated the functional consequences of three naturally occurring amino acid substitutions of the human mineralocorticoid receptor (hMR). These mutations are located in the DNA-binding domain and the ligand-binding domain (LBD) and are associated with autosomal dominant or sporadic type I pseudohypoaldosteronism. All mutant receptors bound specifically to glucocorticoid-responsive elements but presented modified transcriptional properties. The DNA-binding domain mutant G633R, which possesses a normal affinity for a glucocorticoid-responsive element, displayed altered interaction with, and a reduced dissociation rate from, DNA. Its intracellular localization in the absence of hormone was predominantly nuclear in comparison with predominant cytoplasmic location of hMR. Hormone-dependent nuclear cluster formation was comparable to wild-type hMR. These results and the three-dimensional modeling of the interaction of R633 with DNA suggest that altered interaction dynamics with DNA as well as modified intracellular localization may be responsible for submaximal transcriptional potency of hMR. Two LBD mutations, Q776R and L979P, were also investigated. Our data confirm the fundamental role of amino acid Q776 for anchoring the C3 ketone group of steroids in the ligand-binding pocket. Analysis of LBD conformation of mutant P979 demonstrates the relevance of hydrophobic interactions in the extreme C-terminal tail of the hMR for the correct ligand-binding competent state of the receptor. Our data underline the importance of studying naturally occurring mutants to identify crucial residues involved in hMR function.
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Mutación Missense/genética , Seudohipoaldosteronismo/genética , Receptores de Mineralocorticoides/genética , Receptores de Mineralocorticoides/metabolismo , Activación Transcripcional/genética , Aldosterona/farmacología , Secuencia de Aminoácidos , Sustitución de Aminoácidos/genética , Animales , Núcleo Celular/química , Núcleo Celular/metabolismo , Células Cultivadas , ADN/metabolismo , Humanos , Espacio Intracelular/química , Espacio Intracelular/metabolismo , Túbulos Renales Colectores/citología , Túbulos Renales Colectores/fisiología , Ligandos , Datos de Secuencia Molecular , Conformación Proteica , Transporte de Proteínas/efectos de los fármacos , Transporte de Proteínas/genética , Conejos , Receptores de Mineralocorticoides/químicaRESUMEN
Aldosterone excess can produce heart and kidney fibrosis, which seem to be related to a direct effect of aldosterone at the level of specific receptors. We report a direct, mineralocorticoid-mediated effect on the protein expression of two markers of oxidative stress after incubation of mononuclear leukocytes with 1 x 10(-8) M aldosterone (p22(phox)/beta-actin = 1.38 +/- 0.05 and PAI-1/beta-actin = 1.80 +/- 0.05). The same effect was also found with 3 x 10(-5) M glycyrrhetinic acid, the principal constituent of licorice root (p22(phox)/beta-actin = 1.37 +/- 0.97 and PAI-1/beta-actin = 1.80 +/- 0.04). The effect of both aldosterone and glycyrrhetinic acid is blocked by incubation with added 1 x 10(-6) M of receptor-antagonist canrenone. Canrenone alone did not show any effect. PAI-1 related protein was also found using 4 x 10(-9) M aldosterone. Incubations with 1 x 10(-9) M for 3 hours as well as 1 x 10(-8) M aldosterone for 5, 10, and 20 minutes were ineffective for both proteins. These data support the previous finding of an involvement of mononuclear leukocytes in the pathogenesis of the oxidative stress induced by hyperaldosteronism. In addition, the results confirm our previous data on a direct effect of glycyrrhetinic acid at the level of mineralocorticoid receptors.
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Aldosterona/farmacología , Ácido Glicirretínico/farmacología , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/metabolismo , Proteínas de Transporte de Membrana/sangre , NADPH Deshidrogenasa/sangre , Fosfoproteínas/sangre , Inhibidor 1 de Activador Plasminogénico/sangre , Adulto , Aldosterona/administración & dosificación , Canrenona/farmacología , Relación Dosis-Respuesta a Droga , Sinergismo Farmacológico , Femenino , Humanos , Masculino , Antagonistas de Receptores de Mineralocorticoides/farmacología , NADPH OxidasasRESUMEN
Alzheimer's disease is often characterized by an increase in plasma cortisol without clinical evidence of hypercorticism. Twenty-three consecutive patients with Alzheimer's disease and 23 age- and sex-matched healthy controls were studied by measuring plasma cortisol and dehydroepiandrosterone sulfate (DHEAS) (by enzyme immunoassay), the number of type I and type II corticosteroid receptors in mononuclear leukocytes (by radio-receptor-assay), and the lymphocyte subpopulations (by cytofluorimetry). Results are expressed in terms of median and range. In Alzheimer's disease, plasma cortisol was higher than in controls (median 0.74, range 0.47-1.21 vs 0.47, 0.36-0.77 mmol/L; p < 0.001). Plasma DHEAS, the DHEAS/cortisol ratio, and the number of type II corticosteroid receptors were significantly lower in AD than in controls (DHEAS: median 1.81, range 0.21-3.69 vs 3.51, 1.35-9.07 micromol/L; DHEAS/ cortisol: 2.04, range 0.3-5.8 vs 6.8, range 2.7-24 and type II receptors: 1219, 1000-2700 vs 1950, 1035- 2750 receptors per cell; p < 0.001). No correlation was found between the hormonal parameters, age, and mini-mental test score. These data support the hypothesis of a dysregulation of the adrenal pituitary axis in Alzheimer's disease, which is probably the consequence of damage to target tissues by corticosteroids.
Asunto(s)
Enfermedad de Alzheimer/sangre , Deshidroepiandrosterona/sangre , Hidrocortisona/sangre , Linfocitos/metabolismo , Receptores de Esteroides/metabolismo , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/fisiopatología , Estudios de Casos y Controles , Femenino , Citometría de Flujo , Humanos , Inmunoensayo , Masculino , Persona de Mediana Edad , Ensayo de Unión RadioliganteRESUMEN
We have analyzed the human mineralocorticoid receptor (hMR) gene in 14 families with autosomal dominant or sporadic pseudohypoaldosteronism (PHA1), a rare form of mineralocorticoid resistance characterized by neonatal renal salt wasting and failure to thrive. Six heterozygous mutations were detected. Two frameshift mutations in exon 2 (insT1354, del8bp537) and one nonsense mutation in exon 4 (C2157A, Cys645stop) generate truncated proteins due to premature stop codons. Three missense mutations (G633R, Q776R, L979P) differently affect hMR function. The DNA binding domain mutant R633 exhibits reduced maximal transactivation, although its binding characteristics and ED(50) of transactivation are comparable with wild-type hMR. Ligand binding domain mutants R776 and P979 present reduced or absent aldosterone binding, respectively, which is associated with reduced or absent ligand-dependent transactivation capacity. Finally, P979 possesses a transdominant negative effect on wild-type hMR activity, whereas mutations G633R and Q776R probably result in haploinsufficiency in PHA1 patients. We conclude that hMR mutations are a common feature of autosomal dominant PHA1, being found in 70% of our familial cases. Their absence in some families underscores the importance of an extensive investigation of the hMR gene and the role of precise diagnostic procedures to allow for identification of other genes potentially involved in the disease.