We sought to measure the clinical benefits of adrenal venous sampling (AVS), a test recommended by guidelines for primary aldosteronism (PA) patients seeking surgical cure, in a large registry of PA patients submitted to AVS. Data of 1625 consecutive patients submitted to AVS in 19 tertiary referral centers located in Asia, Australia, Europe, and North America were collected in a large multicenter international registry. The primary end points were the rate of bilateral success, ascertained lateralization of PA, adrenalectomy, and of cured arterial hypertension among AVS-guided and non AVS-guided adrenalectomy patients. AVS was successful in 80.1% of all cases but allowed identification of unilateral PA in only 45.5% by the criteria in use at each center. Adrenalectomy was performed in 41.8% of all patients and cured arterial hypertension in 19.6% of the patients, 2-fold more frequently in women than men ( P <0.001). When AVS-guided, surgery provided a higher rate of cure of hypertension than when non-AVS-guided (40.0% versus 30.5%; P =0.027). Compared with surgical cases, patients treated medically needed more antihypertensive medications ( P <0.001) and exhibited a higher rate of persistent hypokalemia requiring potassium supplementation (4.9% versus 2.3%; P <0.01). The low rate of adrenalectomy and cure of hypertension in PA patients seeking surgical cure indicates suboptimal AVS use, possibly related to issues in patient selection, technical success, and AVS data interpretation. Given the better outcomes of AVS-guided adrenalectomy, these results call for actions to improve the diagnostic use of this test that is necessary for detection of surgical PA candidates. Clinical Trial Registration— URL: http://www.clinicaltrials.gov . Unique identifier: NCT01234220.

Context Accumulating evidence suggests a link between adrenocortical zona glomerulosa and parathyroid gland through mechanisms that remain unexplored. Objectives To test the hypothesis that in vivo angiotensin II blockade affects PTH secretion in patients with hypertension and that aldosterone and angiotensim II directly stimulate PTH secretion ex vivo. Design and Setting We investigated the changes of serum PTH levels induced by oral captopril (50 mg) administration in patients with primary essential hypertension (EH) and with primary aldosteronism (PA) caused by bilateral adrenal hyperplasia (BAH) or aldosterone-producing adenoma (APA), the latter before and after adrenalectomy. We also exposed primary cultures of human parathyroid cells from patients with primary hyperparathyroidism to angiotensin II (10−7 M) and/or aldosterone (10−7 M). Results Captopril lowered PTH levels (in nanograms per liter) both in patients with EH (n = 63; 25.9 ± 8.3 baseline vs 24.4 ± 8.0 postcaptopril, P < 0.0001) and in patients with APA after adrenalectomy (n = 27; 26.3 ± 11.6 vs 24.0 ± 9.7 P = 0.021). However, it was ineffective in patients with full-blown PA caused by APA and BAH. In primary culture of human parathyroid cells, both aldosterone (P < 0.001) and angiotensin II (P = 0.002) markedly increased PTH secretion from baseline, by acting through mineralocorticoid receptor and angiotensin type 1 receptor, as these effects were abolished by canrenone and irbesartan, respectively. Conclusion These results collectively suggest an implication of the renin-angiotensin-aldosterone system in PTH regulation in humans, at least in PTH-secreting cells obtained from parathyroid tumors. Moreover, they further support the concept that mild hyperparathyroidism is a feature of human PA that is correctable with adrenalectomy.

The angiotensin II (Ang II) type 2 receptor (AT2R) and the angiotensin-(1-7) (Ang-(1-7)) receptor (MasR) play a cardiovascular protective role by counter-regulating Ang II type 1 receptor (AT1R)-mediated effects, but whether this involves blunting of adrenocortical hormone secretion is unknown. We investigated the presence of AT1R, AT2R, and MasR in aldosterone-producing adenoma (APA), a condition featuring hyperaldosteronism, and in APA-adjacent tissue. The effect of Compound 21 (C21), an AT2R agonist, on CYP11B1 (cortisol synthase) and CYP11B2 (aldosterone synthase) gene expression in NCI-H295R and HAC15 cell lines, and in APA and APA-adjacent tissue, was also assessed using the AT1R antagonist irbesartan to ascertain the specificity of C21 effect. We found that the AT1R, AT2R, and MasR were expressed in APA and APA-adjacent tissue, albeit heterogeneously. The gene expression of AT1R and AT2R was lower, and that of the MasR higher in APAs than in APA-adjacent tissue. In steroid-producing NCI-H295R and HAC15 cell lines, and in APA and APA-adjacent tissue, C21 was ineffective at nanomolar concentrations, but increased CYP11B1 and CYP11B2 gene expression at micromolar concentrations through AT1R, as this effect was blunted by irbesartan. The scant expression of the AT2R, along with the lack of any effect of C21 at low concentrations on CYP11B2, do not support the contention that the protective arm of renin-angiotensin system (RAS) blunts aldosterone synthase in the normal adrenal cortex and primary aldosteronism.

Mutations within the glucocorticoid receptor (GR) gene locus lead to glucocorticoid resistance which is characterized by several clinical symptoms such as adrenal gland hyperplasia and salt-sensitive hypertension, although the underlying mechanisms are still unknown. We studied GR haploinsufficient (GR+/−) Sprague Dawley rats which, on a standard diet, showed significantly increased plasma aldosterone and corticosterone levels and an adrenocortex hyperplasia accompanied by a normal systolic blood pressure. Following a high salt diet, these rats developed salt-sensitive hypertension and maintained elevated enzyme-soluble epoxide hydrolase (sEH) in adrenal glands, while sEH was significantly decreased in wild-type rats. Furthermore, GR+/− rats showed dysregulation of the equilibrated linoleic and arachidonic acid pathways, with a significant increase of less active metabolites such as 8,9-DiHETrE. In Sprague Dawley rats, GR haploinsufficiency induced steroid disturbances, which provoked hypertension only in combination with high salt intake, which was accompanied by disturbances in sEH and fatty acid metabolism. Our results suggest that sEH inhibition could be a potential target to treat hypertension in patients with GR haploinsufficiency.

The branch of the renin-angiotensin system constituting angiotensin-(1-7) [Ang-(1-7)], the Ang II type 2 receptor, the Mas receptors and the Ang-(1-7)-forming enzyme ACE-2, by counteracting the Ang II type 1 receptor (AT1R)-mediated effects, are held to be cardiovascular protective in several conditions. However, whether Ang-(1-7) and ACE-2 are detectable in human adrenocortical tissues and whether they affect aldosterone and cortisol biosynthesis was unknown. Methods:We measured angiotensin peptides with liquid chromatography tandem-mass spectrometry and ACE-2 mRNA with digital droplet (dd)PCR in human aldosteroneproducing adenoma (APA) and APA-adjacent tissue obtained from patients with primary aldosteronism. We also investigated the effects of Ang-(1-7) and the ACE-2 activator diminazene aceturate (DIZE) on aldosterone synthase (CYP11B2) and 11b-hydroxylase (CYP11B1) gene expression, in the absence or presence of the AT1R antagonist irbesartan, or of the MasR antagonist A779.Results: APA and APA-adjacent adrenocortical tissues express ACE-2 mRNA and contain detectable amounts of Ang II and Ang-(2-8), but not of Ang I, Ang-(1-5), Ang (3-8) and Ang-(1-7). Under unstimulated and Ang IIstimulated conditions Ang-(1-7) did not blunt CYP11B1 and CYP11B2 mRNA. At supraphysiological concentrations (10 À4 mol/l), Ang-(1-7) stimulated both CYP11B1 and CYP11B2 mRNA via the AT1R. The ACE-2 activator DIZE increased by 1.5-fold ACE-2 mRNA but did not blunt Ang II-upregulated CYP11B1 and CYP11B2 expression. Conclusion:These results do not support the hypothesis that the ACE-2/Ang-(1-7)/MasR axis play a protective role by counteracting enhanced aldosterone secretion in humans.

Regular exercise confers multifaceted and well-established health benefits. Yet, transient and asymptomatic increases in markers of cardio-renal injury are commonly observed in ultra-endurance athletes during and after competition. This has raised concerns that chronic recurring insults could cause long-term cardiac and/or renal damage. Indeed, extreme endurance exercise (EEE) over decades has sometimes been linked with untoward cardiac effects, but a causal relation with acute injury markers has not yet been established. Here, we summarize the current knowledge on markers of cardiac and/or renal injury in EEE athletes, outline the possible interplay between cardiac and kidney damage, and explore the roles of various factors in the development of potential exercise-related cardiac damage, including underlying diseases, medication, sex, training, competition, regeneration, mitochondrial dysfunction, oxidative stress, and inflammation. In conclusion, despite the undisputed health benefits of regular exercise, we speculate, based on the intimate link between heart and kidney diseases, that in rare cases excessive endurance sport may induce adverse cardio-renal interactions that under specific, hitherto undefined conditions could result in persistent cardiac damage. We highlight future research priorities and provide decision support for athletes and clinical consultants who are seeking safe strategies for participation in EEE training and competition.

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Background: Guidelines recommend Adrenal vein sampling (AVS) for the subtyping of primary aldosteronism (PA), the most common curable cause of arterial hypertension. How this recommendation is implemented in practice remains uncertain. Hence, in 2011 upon completion of the AVIS-1 Study we launched the AVIS-2 Study to determine: 1) the success rate of the AVS studies performed in major referral centers worldwide; 2) the impact of AVS results on the clinical decision making and on outcome of the patients at follow-up. Methods: All the AVIS-1 Study centers were invited to join the AVIS-2 by entering the individual PA patients AVS and clinical data in an ad hoc predefined web-based database. Data were analyzed according to use of cosyntropin unstimulated or -stimulated protocols. Results and Conclusions: Sixteen centers in Europe, North America and Asia recruited a total of 1656 PA patients (age 50 years ± 10; 39.5% females). The AVS success rate was examined as a function of the Selectivity Index (SI) cutoffs. Among unstimulated AVS (n = 1307), the rate of bilaterally selective tests fell from 86% to 53% and 45% with cut off values of 1.10, 2.00 and 3.00, respectively; for adrenalectomized patients (49% of total), the decision was based on bilateral selective AVS in 71%, 56% and 43% of cases, respectively. Among cosyntropin-stimulated AVS, 85%, 80%, 76% and 72% were bilaterally selective, with a cut-off of 2.00, 3.00, 4.00, and 5.00, respectively; the rate of adrenalectomy based on AVS data fell from 47% with a cut-off = 2.00 to 40% with a cut-off = 5.00. The lateralization index value did not improve by comparing those with SI bilaterally > 2.0 (baseline) and > 5.0 after cosyntropin (3.8 [median, 1.6-12.7 IQR] vs 3.7 [1.5-14.0]). Conclusions: Only a minority of PA submitted to AVS have bilaterally selective studies if high cutoffs for the SI are used. Moreover, in even less patients AVS eventually led to adrenalectomy. These intriguing results from the largest dataset of AVS studies provide compelling evidence for the need of further prospective studies in this field.