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Phaeochromocytomas and paragangliomas (PPGLs) are tumours of the adrenal medulla and extra-adrenal sympathetic nervous system which often secrete catecholamines. Variants of the SDHX (SDHA, -AF2, -B, -C, -D) genes are a frequent cause of familial PPGLs. In this study from a single tertiary centre, we aimed to characterise the genotype–phenotype associations in patients diagnosed with germline variants in SDHX genes. We also assessed whether systematic screening of family members resulted in earlier detection of tumours. The study cohort comprised all individuals (n = 59) diagnosed with a rare variant in SDHX during a 13-year period. Patient- and pathology records were checked for clinical characteristics and histopathological findings. We found distinct differences in the clinical and histopathological characteristics between genetic variants in SDHB. We identified two SDHB variants with distinct phenotypical patterns. Family screening for SDHB variants resulted in earlier detection of tumours in two families. Patients with SDHA, SDHC and SDHD variants also had malignant phenotypes, underlining the necessity for a broad genetic screening of the proband. Our study corroborates previous findings of poor prognostic markers and found that the genetic variants and clinical phenotype are linked and, therefore, useful in the decision of clinical follow-up. Regular tumour screening of carriers of pathogenic variants may lead to an earlier diagnosis and expected better prognosis. The development of a combined algorithm with clinical, genetic, morphological, and biochemical factors may be the future for improved clinical risk stratification, forming a basis for larger multi-centre follow up studies.

The overproduction of adrenocorticotropic hormone (ACTH), in conditions such as Cushing’s disease and congenital adrenal hyperplasia (CAH), leads to significant morbidity. Current treatment with glucocorticoids does not adequately suppress plasma ACTH, resulting in excess adrenal androgen production. At present, there is no effective medical treatment in clinical use that would directly block the action of ACTH. Such a therapy would be of great clinical value. ACTH acts via a highly selective receptor, the melanocortin-2 receptor (MC2R) associated with its accessory protein MRAP. ACTH is the only known naturally occurring agonist for this receptor. This lack of redundancy and the high degree of ligand specificity suggest that antagonism of this receptor could provide a useful therapeutic strategy in the treatment of conditions of ACTH excess. To this end, we screened an extensive library of low-molecular-weight drug-like compounds for MC2R antagonist activity using a high-throughput homogeneous time-resolved fluorescence cAMP assay in Chinese hamster ovary cells stably co-expressing human MC2R and MRAP. Hits that demonstrated MC2R antagonist properties were counter-screened against the β2 adrenergic receptor and dose–response analysis undertaken. This led to the identification of a highly specific MC2R antagonist capable of antagonising ACTH-induced progesterone release in murine Y-1 adrenal cells and having selectivity for MC2R amongst the human melanocortin receptors. This work provides a foundation for the clinical investigation of small-molecule ACTH antagonists as therapeutic agents and proof of concept for the screening and discovery of such compounds.

Primary aldosteronism is a natural model for chronic aldosterone excess in humans and associated with symptoms of anxiety and depression. Cognitive deficits are inherent to the symptomatology of depression and anxiety disorders. Mineralocorticoid receptors and aldosterone appear to play a role in memory. Aldosterone was additionally supposed to be a risk factor for cognitive decline in patients with essential hypertension. The objective of this study was to investigate possible effects of chronically high aldosterone concentrations on cognitive function. A range of cognitive dimensions were assessed in 19 patients (9 males, 10 females); mean age 47.1 (12.5) under standardized treatment and several rating scales for anxiety, depression, quality of life and sleep were administered. Cognitive parameters were compared to standard norms from a large, healthy standardization sample. Patients showed increased levels of anxiety and depression without meeting diagnostic criteria for a disorder. Besides a numerically lower attention score, patients did not show any significant differences in the cognitive dimensions. Anxiety and depression were negatively correlated with quantitative performance in males. In females, a negative correlation between sleep disturbances and abstract reasoning and a positive correlation with quantitative performance were found. Our data showed no specific effect of chronic aldosterone in the tested cognitive parameters overall at least in younger patients, but they indicate sexually dimorphic regulation processes.

Pheochromocytoma and paragangliomas (PCC/PGL) are neuroendocrine tumors that arise from chromaffin cells of the adrenal medulla and sympathetic/parasympathetic ganglia, respectively. Of clinical relevance regarding diagnosis is the highly variable presentation of symptoms in PCC/PGL patients. To date, the clear-cut correlations between the genotypes and phenotypes of PCC/PGL have not been entirely established. In this study, we reviewed the medical records of PCC/PGL patients with pertinent clinical, laboratory and genetic information. Next-generation sequencing (NGS) performed on patient samples revealed specific germline mutations in the SDHB (succinate dehydrogenase complex iron-sulfur subunit B) and SDHD (succinate dehydrogenase complex subunit D) genes and these mutations were validated by Sanger sequencing. Of the 119 patients, two were identified with SDHB mutation and one with SDHD mutation. Immunohistochemical (IHC) staining was used to analyze the expression of these mutated genes. The germline mutations identified in the SDH genes were c343C>T and c.541-542A>G in the SDHB gene and c.334-337delACTG in the SDHD gene. IHC staining of tumors from the c.343C>T and c.541-2A>G carriers showed positive expression of SDHB. Tumors from the c.334-337delACTG carrier showed no expression of SDHD and a weak diffused staining pattern for SDHB. We strongly recommend genetic testing for suspected PCC/PGL patients with a positive family history, early onset of age, erratic hypertension, recurrence or multiple tumor sites and loss of SDHB and/or SDHD expression. Tailored personal management should be conducted once a patient is confirmed as an SDHB and/or SDHD mutation carrier or diagnosed with PCC/PGL.

In the brain, angiotensinergic pathways play a major role in chronic regulation of cardiovascular and electrolyte homeostasis. Increases in plasma angiotensin II (Ang II), aldosterone, [Na⁺] and cytokines can directly activate these pathways. Chronically, these stimuli also activate a slow neuromodulatory pathway involving local aldosterone, mineralocorticoid receptors (MRs), epithelial sodium channels and endogenous ouabain (EO). This pathway increases AT₁R and NADPH oxidase subunits and maintains/further increases the activity of angiotensinergic pathways. These brain pathways not only increase the setpoint of sympathetic activity per se, but also enhance its effectiveness by increasing plasma EO and EO-dependent reprogramming of arterial and cardiac function. Blockade of any step in this slow pathway or of AT₁R prevents Ang II-, aldosterone- or salt and renal injury-induced forms of hypertension. MR/AT₁R activation in the CNS also contributes to the activation of sympathetic activity, the circulatory and cardiac RAAS and increase in circulating cytokines in HF post MI. Chronic central infusion of an aldosterone synthase inhibitor, MR blocker or AT₁R blocker prevents a major part of the structural remodeling of the heart and the decrease in LV function post MI, indicating that MR activation in the CNS post MI depends on aldosterone, locally produced in the CNS. Thus, Ang II, aldosterone and EO are not simply circulating hormones that act on the CNS but rather they are also paracrine neurohormones, locally produced in the CNS, that exert powerful effects in key CNS pathways involved in the long-term control of sympathetic and neuro-endocrine function and cardiovascular homeostasis.