Epigenetic alterations of 11beta-hydroxysteroid dehydrogenase 1 gene in the adipose tissue of patients with primary aldosteronism.

11Beta-hydroxysteroid dehydrogenase 1 (11ß-HSD1) is a key enzyme involved in metabolic syndrome. Transcript-specific epigenetic regulation of the gene encoding 11ß-HSD1 (HSD11B1) has been reported. We examined the mRNA level and methylation status of the HSD11B1 promoter region in the adipose tissue of patients with primary aldosteronism (PA). We compared 10 tissue specimens from patients with PA caused by aldosterone-producing adenoma (APA) with 8 adipose tissue specimens from patients with subclinical Cushing's syndrome (SCS) caused by cortisol-producing adenomas, 4 tissue specimens from patients with Cushing's adenoma (Cu), or 7 tissue specimens from patients with non-functioning adrenal adenoma (NFA). PA, SCS, and Cu were diagnosed according to the guideline of the Japan Endocrine Society. The mRNA level of HSD11B1 was quantified using real-time PCR. Isolated DNA was treated with bisulfite and amplified using primers specific to the human HSD11B1 promoter region. The glycohemoglobin level was significantly higher in patients with APA, SCS, or Cu than in those with NFA (p < 0.05). Blood pressure was significantly higher in patients with APA than in those with SCS, Cu, or NFA (p < 0.01). The HSD11B1 mRNA level was significantly increased in the adipose tissues of APA or SCS patients compared with Cu or NFA patients (p < 0.05). The methylation ratio was significantly lower in SCS patients than in APA, Cu, or NFA patients (p < 0.05). HSD11B1 expression is partly controlled by an epigenetic mechanism in human tissues. The pathophysiological role of epigenetic regulation of HSD11B1 expression in adipose tissue requires further study.

Molecular and Epigenetic Control of Aldosterone Synthase, CYP11B2 and 11-Hydroxylase, CYP11B1.

Aldosterone and cortisol serve important roles in the pathogenesis of cardiovascular diseases and metabolic disorders. Epigenetics is a mechanism to control enzyme expression by genes without changing the gene sequence. Steroid hormone synthase gene expression is regulated by transcription factors specific to each gene, and methylation has been reported to be involved in steroid hormone production and disease. Angiotensin II or potassium regulates the aldosterone synthase gene, CYP11B2. The adrenocorticotropic hormone controls the 11b-hydroxylase, CYP11B1. DNA methylation negatively controls the CYP11B2 and CYP11B1 expression and dynamically changes the expression responsive to continuous stimulation of the promoter gene. Hypomethylation status of the CYP11B2 promoter region is seen in aldosterone-producing adenomas. Methylation of recognition sites of transcription factors, including cyclic AMP responsive element binding protein 1 or nerve growth factor-induced clone B, diminish their DNA-binding activity. A methyl-CpG-binding protein 2 cooperates directly with the methylated CpG dinucleotides of CYP11B2. A low-salt diet, treatment with angiotensin II, and potassium increase the CYP11B2 mRNA levels and induce DNA hypomethylation in the adrenal gland. A close association between a low DNA methylation ratio and an increased CYP11B1 expression is seen in Cushing's adenoma and aldosterone-producing adenoma with autonomous cortisol secretion. Epigenetic control of CYP11B2 or CYP11B1 plays an important role in autonomic aldosterone or cortisol synthesis.

Impact of Conducting Adrenal Venous Sampling in the Morning Versus Afternoon in Primary Aldosteronism.

Context: Adrenal venous sampling (AVS) is the gold standard technique for subtype differentiation of primary aldosteronism (PA) and to obtain aldosterone and cortisol measurements; however, their secretion patterns show fluctuations during the day. Objective: We aimed to examine the effects of AVS timing on AVS results. Methods: This multicenter, retrospective, observational study included a total of 753 patients who were diagnosed with PA and underwent AVS in 4 centers in Japan. Among them, 504 and 249 patients underwent AVS in the morning (AM-AVS) and in the afternoon (PM-AVS), respectively. The outcome measures were the impact of AVS timing and hormone fluctuations in a day on AVS results. Results: There were no differences in the success rate of AVS, diagnostic rate of disease type, or frequency of discrepancy in PA subtypes between the AM-AVS and PM-AVS groups. Regarding patients with unilateral PA, aldosterone concentrations in adrenal venous blood did not differ between the 2 groups on the dominant or nondominant side. Conversely, regarding patients with bilateral PA, aldosterone concentrations in adrenal venous blood were significantly higher in the AM-AVS than in the PM-AVS group. Conclusions: The timing of AVS did not seem to have a significant impact on subtype diagnosis. The aldosterone levels in adrenal venous blood were significantly higher in patients with bilateral PA in the AM-AVS group, but there was no such difference between patients with unilateral PA in the AM-AVS and PM-AVS groups. Each subtype may have a different hormone secretion pattern in a day.

Penile and scrotal oedema along with urinary retention after insulin therapy.

Insulin oedema is a rare complication of insulin treatment characterised by an absence of heart, liver and renal involvement. Insulin oedema typically develops in the lower extremities or, less frequently, as generalised oedema after initiation of insulin therapy. We report a 59-year-old man with poorly controlled type 2 diabetes who developed oedema in his penis and scrotum accompanied by weight gain following intensive insulin therapy. His oedema improved after reduction of the daily insulin injection dose and treatment for urinary retention. Penile and scrotal oedema is a rare physical finding for the patient with diabetes. Therefore, in patients with poorly controlled diabetes who have started insulin therapy, physicians should pay attention to urinary retention and do not miss changes in weight gain or oedema in the lower body, including the perineal region.

DNA Methylation of the Angiotensinogen Gene, AGT, and the Aldosterone Synthase Gene, CYP11B2 in Cardiovascular Diseases.

Angiotensinogen (AGT) and aldosterone play key roles in the regulation of blood pressure and are implicated in the pathogenesis of cardiovascular diseases. DNA methylation typically acts to repress gene transcription. The aldosterone synthase gene CYP11B2 is regulated by angiotensin II and potassium. DNA methylation negatively regulates AGT and CYP11B2 expression and dynamically changes in response to continuous promoter stimulation of each gene. High salt intake and excess circulating aldosterone cause DNA demethylation around the CCAAT-enhancer-binding-protein (CEBP) sites of the CYP11B2 promoter region, thereby converting the phenotype of AGT expression from an inactive to an active state in visceral adipose tissue and heart. A close association exists between low DNA methylation at CEBP-binding sites and increased AGT expression in salt-sensitive hypertensive rats. Salt-dependent hypertension may be partially affected by increased cardiac AGT expression. CpG dinucleotides in the CYP11B2 promoter are hypomethylated in aldosterone-producing adenomas. Methylation of recognition sequences of transcription factors, including CREB1, NGFIB (NR4A1), and NURR1 (NR4A2) diminish their DNA-binding activity. The methylated CpG-binding protein MECP2 interacts directly with the methylated CYP11B2 promoter. Low salt intake and angiotensin II infusion lead to upregulation of CYP11B2 expression and DNA hypomethylation in the adrenal gland. Treatment with the angiotensin II type 1 receptor antagonist decreases CYP11B2 expression and leads to DNA hypermethylation. A close association between low DNA methylation and increased CYP11B2 expression are seen in the hearts of patients with hypertrophic cardiomyopathy. These results indicate that epigenetic regulation of both AGT and CYP11B2 contribute to the pathogenesis of cardiovascular diseases.

Primary Aldosteronism with Parathyroid Hormone Elevation: A Single-center Retrospective Study.

Objective Primary aldosteronism (PA) is a major cause of secondary hypertension. The association between PA and other hormone disorders is unclear. The present study aimed to evaluate whether the parathyroid hormone (PTH) value is associated with PA subtypes or specific treatments. Methods We enrolled 135 patients with PA who had their PTH value measured before undergoing a specific treatment. We evaluated whether PTH value is associated with PA subtypes or with specific treatments. The present study is a single-center retrospective study (2011-2018). Results Our study showed that, among the patients with PA, the proportion of those with PTH elevation was >30%. The PTH value was significantly correlated with both the basal plasma aldosterone concentration (PAC) and PAC after a captopril challenge test. However, the PTH value was not significantly different between the patients with unilateral and bilateral PA. We observed that the serum PTH value decreased after treatment of PA with unilateral adrenalectomy or mineralocorticoid receptor antagonists. Conclusion Our findings suggest that the PTH value in PA patients might be associated with the autonomous production of aldosterone. However, there was no correlation between the PTH value and PA subtypes in our study. Additionally, our study showed that targeted treatment for PA may lead to a decrease in the serum PTH levels. Hence, the PTH value could potentially be used as an index for measuring the suitability for PA treatment.

Effect of potassium on DNA methylation of aldosterone synthase gene.

BACKGROUND: Aldosterone synthase gene, CYP11B2 is regulated by potassium and angiotensin II (Ang II). We have reported that Ang II could change the DNA methylation status around transcription factor-binding sites and a transcription start site (TSS) and activate expression of CYP11B2. Similar to Ang II, small increases in extracellular potassium levels also increase CYP11B2 mRNA levels. METHODS AND RESULTS: Adrenocortical H295R cells were treated with different doses of potassium. Methylation analysis of CYP11B2 promoter region was done by bisulfite sequencing. CYP11B2 mRNA and protein levels, chromatin accessibility, methylation and demethylation activity were estimated. The transcriptional ability of CYP11B2 promoter with or without methylation was assessed. Potassium stimulation caused DNA demethylation around cyclic AMP responsive element binding protein 1 (CREB1) and nuclear receptor subfamily 4 group A (NR4A) family-binding sites and a TSS; demethylation was accompanied by recruitment of CREB1 and NR4A1 and increased chromatin accessibility of the CYP11B2 promoter. DNA methylation activity decreased in the nucleus. DNA demethylation at CpG1 (Ad1), CpG2 (Ad5) and CpG3 were detected within 2 to 4 days after potassium (16 mmol/l) stimulation. The changes reached a maximum level by day 7. DNA at CpG2 (Ad5) and CpG3 was re-methylated to levels that were similar to those of nontreated cells at day 9. Potassium treatment significantly reduced DNA methylation activity at days 7 and 9. DNA demethylation activity was not changed by potassium. CONCLUSION: : Potassium induced reversibly DNA demethylation, which switches the phenotype of CYP11B2 expression from an inactive to an active state.

Impact of mineralocorticoid receptor blockade with direct renin inhibition in angiotensin II-dependent hypertensive mice.

It has been suggested that aldosterone breakthrough during treatment with a type 1 angiotensin II receptor (AT1R) blocker (ARB) may be an important risk factor for the progression of renal and cardiovascular disease. We examined whether the direct renin inhibitor, aliskiren caused aldosterone breakthrough in angiotensin II (Ang II)-dependent hypertensive mice. The effect of combination therapy with aliskiren and eplerenone was compared with that of therapy using renin-angiotensin system (RAS) blockade. Tsukuba hypertensive mice were treated for 12 weeks with aliskiren (30 mg/kg/day, i.p), candesartan (5 mg/kg/day, p.o), eplerenone (100 mg/kg/day, p.o) aliskiren and candesartan, aliskiren and eplerenone or candesartan and eplerenone. Blood pressure, urinary aldosterone and angiotensinogen (AGTN) excretion; plasma endothelin-1 concentration; kidney weight; urinary albumin excretion (UAE); glomerular injury; and renal messenger RNA (mRNA) levels for transforming growth factor (TGF)-ß1, plasminogen activator inhibitor (PAI)-1, angiotensin-converting enzyme (ACE) and AT1R were measured. Combination therapy with aliskiren and candesartan caused a further decrease in blood pressure (p < 0.05) compared with either agent alone. Urinary aldosterone excretion was decreased significantly by 4 weeks of treatment with aliskiren or candesartan (p < 0.05). However, it was increased again by treatment with candesartan or aliskiren for 12 weeks. Combination therapy with aliskiren and eplerenone significantly decreased UAE, the glomerulosclerosis index, and PAI-1 and TGF-ß1 mRNA levels compared with all other therapies (p < 0.05). Treatment with aliskiren decreased urinary aldosterone excretion at 4 weeks and increased it at 12 weeks. Combination therapy with a direct renin inhibitor and a mineralocorticoid receptor blocker may be effective for the prevention of renal injury in Ang II-dependent hypertension.

Pheochromocytoma crisis with cyclic fluctuation in blood pressure mimics acute coronary syndrome.

SUMMARY: Pheochromocytoma crisis results from the sudden release of large quantities of catecholamines and leads to progressive multiple organ dysfunction. Here we report a case of pheochromocytoma crisis with symptoms associated with acute coronary syndrome (ACS) and severe fluctuations in blood pressure (BP). A 43-year-old Japanese man with hypertension (240/120 mmHg) visited a general hospital for chest pain. Echocardiogram showed ST segment depression and blood test demonstrated elevated troponin T. However, emergent coronary angiography revealed normal findings. CT showed a large adrenal mass on the left side, which was suspected as the cause of chest pain and BP elevation. After the patient was transported to our hospital, his BP was found to oscillate between 70 and 240 mmHg, and level of consciousness was decreased. After hospitalization, he had a further decrease in consciousness, a rise in body temperature, and a gradual increase in the interval between the upper and lower systolic BP. His systolic BP varied between 30 mmHg and 300 mmHg at the intervals of 20-30 min. After a multimodality therapy, including α-blocker and high dose fluid replacement, the fluctuation in his BP was gradually decreased and got stabilized after approximately 24 h. Approximately 3 weeks later, he underwent left adrenalectomy. This case showed that pheochromocytoma with internal necrosis might be misdiagnosed as ACS. Furthermore, in cases with a large adrenal tumor and severe elevation or fluctuations of BP, pheochromocytoma should be suspected and treated with α-blockers and fluid replacements as soon as possible prior to surgery. LEARNING POINTS: High catecholamine levels due to pheochromocytoma crisis might cause symptoms associated with acute coronary syndrome. Adrenal tumor with internal necrosis and the elevation or fluctuations of blood pressure should be suspected to be pheochromocytoma. If pheochromocytoma crisis is suspected, the specialist, such as an endocrinologist or a urologist, should intervene, and an α-blocker treatment with adequate fluid replacement therapy should be initiated as soon as possible. Pheochromocytoma multisystem crisis (PMC) is a fatal condition characterized by multiple organ failure, severe blood pressure variability, high fever, and encephalopathy. This is an extremely rare subtype of a very rare disease such as pheochromocytoma. However, because the fatality rate of PMC is high, clinicians should be aware of the symptoms that mark its onset.

Impact of adrenocorticotropic hormone stimulation during adrenal venous sampling on outcomes of primary aldosteronism.

BACKGROUND: Adrenal venous sampling (AVS) is essential for identifying a surgically curable form of primary aldosteronism. Adrenocorticotropic hormone (ACTH) infusion or bolus has been reported to improve the success rate of AVS, although the effects on lateralization and its outcomes in unilateral primary aldosteronism are unclear. METHODS: The success rate and lateralization indices were examined in a cohort of 2197 Japanese patients with primary aldosteronism from 28 centres who underwent AVS. Outcomes were analysed in 267 patients with aldosterone-producing adenomas (APAs). RESULTS: ACTH loading during AVS improved the success rate from 67 to 89%, while lateralization indices decreased from 62 to 28%. Bolus, bolus along with continuous infusion or continuous infusion of ACTH did not affect both indices. The absence of clinical success (i.e. unchanged or increased blood pressure) was 33% and absence of biochemical success (persistent hypokalaemia or persistently raised aldosterone-to-renin ratio, or both) was 15%. The clinical and biochemical success rates did not differ between the three groups [lateralization index >2 in basal condition (LIb) and lateralization index >4 after ACTH loading (lateralization indices), and LIb >2 + lateralization indices<4, LIb<2+lateralization indices>4]. The three groups (LIb>4+lateralization indices>4, LIb>4+lateralization indices<4 and LIb<4+lateralization indices>4) did not show any significant differences of clinical and biochemical outcome. CONCLUSION: ACTH loading during AVS improved the success rate but decreased laterality. ACTH did not affect the clinical and biochemical outcomes in APA patients. These data showed that the use of ACTH during AVS was helpful for improving the success rate, but did not contribute to better outcomes.

Spontaneous Isolated Superior Mesenteric Artery Dissection Requiring Emergent Surgery.

A 52-year-old man with a history of hypertension was referred to our hospital due to persistent abdominal pain. Abdominal palpation revealed remarkable rigidity and rebound tenderness all over the abdomen. Enhanced computed tomography demonstrated the superior mesenteric artery (SMA) dissection with a complete obstruction at the middle part of the SMA. Intraoperative findings showed significant necrosis in the most small intestine and surgical resection was performed. Emergent operation is warranted once abdominal pain becomes uncontrollable or intestinal necrosis is suspected. Physicians should pay careful attention to patients' symptoms and repeatedly perfume physical examinations.

Epigenetic Regulation of Aldosterone Synthase Gene by Sodium and Angiotensin II.

BACKGROUND: DNA methylation is believed to be maintained in adult somatic cells. Recent findings, however, suggest that all methylation patterns are not stable. We demonstrate that stimulatory signals can change the DNA methylation status around transcription factor binding sites and a transcription start site and activate expression of the aldosterone synthase gene (CYP11B2). METHODS AND RESULTS: DNA methylation of CYP11B2 was analyzed in aldosterone-producing adenomas, nonfunctioning adrenal adenomas, and adrenal glands and compared with the gene expression levels. CpG dinucleotides in the CYP11B2 promoter were found to be hypormethylated in tissues with high expression, but not in those with low expression, of CYP11B2. Methylation of the CYP11B2 promoter fused to a reporter gene decreased transcriptional activity. Methylation of recognition sequences of transcription factors, including CREB1, NGFIB (NR4A1), and NURR1 (NR4A2) diminished their DNA-binding activity. A methylated-CpG-binding protein MECP2 interacted directly with the methylated CYP11B2 promoter. In rats, low salt intake led to upregulation of CYP11B2 expression and DNA hypomethylation in the adrenal gland. Treatment with angiotensin II type 1 receptor antagonist decreased CYP11B2 expression and led to DNA hypermethylation. CONCLUSIONS: DNA demethylation may switch the phenotype of CYP11B2 expression from an inactive to an active state and regulate aldosterone biosynthesis.

Insulin Secretion and Risk for Future Diabetes in Subjects with a Nonpositive Insulinogenic Index.

AIM: To characterize subjects with a nonpositive insulinogenic index and longitudinally observe changes in their glucose tolerance. SUBJECTS AND METHODS: A historical cohort study was conducted using data from the medical checkups of public school workers. Indices of insulin secretion and insulin sensitivity derived from oral glucose tolerance test (OGTT) and the incidences of diabetes and impaired glucose tolerance (IGT) were compared among subgroups of subjects with different insulinogenic index (change in insulin/change in glucose over the first 30 min on the OGTT). RESULTS: Of the 1464 nondiabetic subjects at baseline, 72 (4.9%) subjects had a nonpositive insulinogenic index: 42 of those subjects had a nonpositive glucose response (ΔGlu0-30 ≤ 0) and 30 had a nonpositive insulin response (ΔIns0-30 ≤ 0). Compared with subjects who had normal glucose tolerance (NGT) with insulinogenic index ≥ 0.4, subjects with a nonpositive glucose response had a higher first-phase Stumvoll and lower incidences of diabetes and IGT based on a log-rank test (p < 0.05), whereas subjects with a nonpositive insulin response had lower indices of insulin secretion and a higher incidence of diabetes (p < 0.05). CONCLUSIONS: These results demonstrate that in the first 30 min on the OGTT, subjects with a nonpositive insulinogenic index due to a nonpositive glucose response (ΔGlu0-30 ≤ 0) had a lower risk for future diabetes and that subjects with nonpositive insulin response (ΔIns0-30 ≤ 0) had a higher risk for future one.

Effect of sodium glucose cotransporter 2 inhibitors on obstructive sleep apnea in patients with type 2 diabetes.

Obstructive sleep apnea syndrome (OSAS) is often associated with metabolic disorders such as obesity and type 2 diabetes and may contribute to cardiovascular events. A novel class of antidiabetic drugs, the sodium glucose cotransporter 2 inhibitors (SGLT2i) reduce body weight (BW), although there is limited data on their impact on OSAS. We therefore evaluated the effect of SGLT2i on OSAS in patients with type 2 diabetes. The presented study was a retrospective design in 18 patients with type 2 diabetes with OSAS (4 males, age range 39-81 yr) administrated a SGLT2i. HbA1c, BW, body mass index (BMI), blood pressure (BP) and apnea hypopnea index (AHI) were evaluated before and after SGLT2i administration. The relationships between the reduction in AHI and the other variables were examined using Pearson correlation analysis. We have got result that SGLT2i reduced AHI from 31.9 ± 18.0 to 18.8 ± 11.5 events per hr (p = 0.003). HbA1c, BW and BMI decreased significantly, whereas BP did not. The Pearson correlation analysis showed a significant relationship between the reduction in AHI and pre-administration of AHI. In conclusion, SGLT2i reduced not only HbA1c, BW and BMI but also AHI significantly and therefore has potential as an effective treatment of OSAS.

Impact of New Quick Gold Nanoparticle-Based Cortisol Assay During Adrenal Vein Sampling for Primary Aldosteronism.

CONTEXT: Adrenal vein sampling (AVS) is essential for identifying a surgically curable form of primary aldosteronism (PA), but accurate placement of the sampling catheter is technically challenging. Intraprocedural cortisol measurement can confirm the catheter's position, thereby increasing the AVS success rate. OBJECTIVE AND METHODS: We developed a quick cortisol assay (QCA) that uses immunochromatography and gold nanoparticles and can be performed either semiquantitatively or quantitatively. The assay was evaluated in two studies. In a single-center study, PA patients were assigned to undergo AVS incorporating the semiquantitative QCA (n = 30), the quantitative QCA (n = 30), or without the QCA (n = 30), and the rates of successful AVS were determined. In a prospective multicenter randomized, controlled study, the success rates of AVS performed with (n = 148) or without (n = 145) the semiquantitative QCA were determined. RESULTS: Cortisol concentrations were measured during AVS in 6 minutes or less in the radiology suite, without additional technical assistance, and significantly correlated with a conventional reference assay (R(2) = 0.994; P < .001). In the single-center study, the differences in the AVS success rates associated with semiquantitative and quantitative QCAs were not significant (both 93%); however, the success rates were significantly higher than the rate of successful AVS performed without using the QCA (63%; P < .001). The success rate of AVS performed in the multicenter study was 94% for the semiquantitative QCA, which was significantly higher than the rate for the patients without QCA (60%; P < .001). CONCLUSIONS: Our novel QCA was rapidly and easily performed at the point of care and improved the rate of successful AVS.