An excess of aldosterone results in cardiac remodelling and fibrosis. Interleukin-6 (IL-6) is a key mediator in the fibrotic process; however, the effect of aldosterone on the expression of IL-6 remains unclear. We investigated whether aldosterone induces the expression of IL-6 and thereby contributes to the fibrotic process. In this clinical study, we prospectively enrolled 25 patients with primary aldosteronism (PA) and 26 patients with essential hypertension (EH). The PA patients had higher plasma IL-6 levels, left ventricular mass index, degree of myocardial fibrosis, and more impaired diastolic function than the EH patients. In addition, plasma IL-6 levels were positively correlated with 24-h urinary aldosterone and echocardiographic parameters. In cell studies, we investigated the possible molecular mechanism how aldosterone-induced IL-6 secretion and the further effects of collagen production. Aldosterone significantly induced IL-6 protein and mRNA production in human umbilical vein endothelial cells. Intracellular signalling occurred through the mineralocorticoid receptor/PI3K/Akt/NF-kB pathway. In cardiac fibroblasts, IL-6 trans-signalling played a critical role in aldosterone-induced IL-6-enhanced fibrosis-related factor expression. To further investigate the role of IL-6 trans-signalling in aldosterone-induced cardiac fibrosis, we measured the severity of myocardial fibrosis in aldosterone infusion mice models including an IL-6 chemical inhibitor and Sgp130 Knockin Transgenic Mice. Mice receiving recombinant soluble gp130 and Sgp130 Knockin Transgenic Mice prevented myocardial fibrosis and cardiac hypertrophy by aldosterone infusion. IL-6 trans-signalling contributes to aldosterone-induced cardiac fibrosis.

Extra-corporeal membranous oxygenation (ECMO) has been applied in patients with cardiopulmonary failure. One critical drawback of peripheral ECMO is an increase in left ventricular (LV) afterload which could be counterbalanced by the combination of intra-aortic balloon counter-pulsation (IABP) therapy. We hypothesized that an add-on therapy with IABP could improve outcomes in patients receiving ECMO support. We included patients (>18 years old) from 2002 to 2013 requiring ECMO support due to cardiogenic shock in a medical center. A total of 529 patients (227 ECMO alone and 302 combined IABP plus ECMO) were included. The mortality rates at 2 weeks (48.5 vs. 47.7%) after ECMO implantation were not different between the two groups (ECMO vs. combined group). After adjustment for propensity score and potential confounders, the odds ratios of outcomes within 14 days (combined group vs. ECMO) for poor LV systolic function, high preload, multi-organ failure and mortality were not different. The results remained similar for subgroup analysis. Compared with ECMO alone, combined IABP and ECMO treatment did not improve outcomes in patients with circulatory failure.

Primary aldosteronism (PA) is characterized by excess production of aldosterone from the adrenal glands and is the most common and treatable cause of secondary hypertension. Aldosterone is a mineralocorticoid hormone that participates in the regulation of electrolyte balance, blood pressure, and tissue remodeling. The excess of aldosterone caused by PA results in an increase in cardiovascular and cerebrovascular complications, including coronary artery disease, myocardial infarction, stroke, transient ischemic attack, and even arrhythmia and heart failure. Endothelial dysfunction is a well-established fundamental cause of cardiovascular diseases and also a predictor of worse clinical outcomes. Accumulating evidence indicates that aldosterone plays an important role in the initiation and progression of endothelial dysfunction. Several mechanisms have been shown to contribute to aldosterone-induced endothelial dysfunction, including aldosterone-mediated vascular tone dysfunction, aldosterone- and endothelium-mediated vascular inflammation, aldosterone-related atherosclerosis, and vascular remodeling. These mechanisms are activated by aldosterone through genomic and nongenomic pathways in mineralocorticoid receptor-dependent and independent manners. In addition, other cells have also been shown to participate in these mechanisms. The complex interactions among endothelium, inflammatory cells, vascular smooth muscle cells and fibroblasts are crucial for aldosterone-mediated endothelial dysregulation. In this review, we discuss the association between aldosterone and endothelial function and the complex mechanisms from a molecular aspect. Furthermore, we also review current clinical research of endothelial dysfunction in patients with PA.

Primary aldosteronism is associated with a higher incidence of left ventricular (LV) hypertrophy and diastolic dysfunction than essential hypertension. However, systolic function via endocardial measurements is similar between patients with primary aldosteronism and essential hypertension. Speckle-tracking echocardiography is a sensitive tool which can detect subclinical impairments in systolic function. The aim of this study was to investigate aldosterone-induced subclinical impairments in systolic function. We prospectively enrolled patients with primary aldosteronism and essential hypertension and analyzed their clinical data, biochemical data, and echocardiographic parameters, including myocardial strain [global longitudinal strain (GLS)]. Thirty-six patients with primary aldosteronism and 31 patients with essential hypertension were enrolled for analysis. The patients with primary aldosteronism had significantly lower serum potassium levels, lower plasma renin activity, higher aldosterone-to-renin ratio (ARR), and higher 24-h urinary aldosterone levels than patients with essential hypertension. With regards to echocardiographic parameters, the patients with primary aldosteronism had a thicker ventricular wall and higher LV mass index than those with essential hypertension. Most importantly, we found significant degradation of GLS in the patients with primary aldosteronism compared with those with essential hypertension (−17.84 ± 2.36 vs. −20.13 ± 2.32, P < 0.001). In correlation analysis, GLS was significantly correlated with serum potassium level, LV mass index, log-transformed plasma renin activity, log-transformed ARR, and log-transformed 24-h urinary aldosterone levels (all P < 0.05). Multivariate linear regression analysis further identified log-transformed ARR (β = 0.771, 95% confidence interval: 0.011–1.530, P = 0.047), and log-transformed 24-h urinary aldosterone level (β = 1.765, 95% confidence interval: 0.01–3.529, P = 0.050) as independent factors correlated with GLS. Patients with primary aldosteronism have a lower magnitude of GLS than patients with essential hypertension, suggesting that aldosterone induces a subclinical decline in LV systolic function.

Aldosterone induces myocardial fibrosis. Tissue inhibitor of metalloproteinases-1 (TIMP-1) is a key factor of myocardial fibrosis. This study tested the hypothesis that aldosterone induces TIMP-1 expression and contributes to the fibrotic process. We prospectively enrolled 54 patients with primary aldosteronism, and measured plasma TIMP-1 and echocardiographic parameters. In the cell study, we investigated the possible molecular mechanism by which aldosterone induces TIMP-1 secretion and the effects on collagen accumulation. In the animal study, we measured serum TIMP-1 levels, cardiac TIMP-1 levels, and cardiac structure in an aldosterone infusion mouse model using implantation of aldosterone pellets. In patients with primary aldosteronism, plasma TIMP-1 was correlated with 24-hour urinary aldosterone, left ventricular mass, and impairment of left ventricular diastolic function. In human cardiac fibroblasts, TIMP-1 protein and mRNA expressions were significantly increased by aldosterone through the glucocorticoid receptor/PI3K/Akt/nuclear factor-κB pathway. TIMP-1 small-interfering RNA significantly reduced aldosterone-induced collagen accumulation, and aldosterone did not alter the levels of collagen1a1 or matrix metalloproteinase-1 mRNA. The aldosterone-induced TIMP-1 expression was inversely related to matrix metalloproteinase-1 activity. Furthermore, in the animal model, the serum and cardiac levels of TIMP-1 were significantly elevated in the mice that received aldosterone infusion. This elevation was blocked by RU-486 but not by eplerenone, suggesting that the effect was through glucocorticoid receptors. In a long-term aldosterone infusion model, serum TIMP-1 was associated with serum aldosterone level, cardiac structure, and fibrosis. In conclusion, aldosterone induced TIMP-1 expression in vivo and in vitro. This increased TIMP-1 expression resulted in enhanced collagen accumulation via the suppression of matrix metalloproteinase-1 activity.

Background: Primary aldosteronism is the most common cause of secondary hypertension and is associated with left ventricular hypertrophy. However, whether aldosterone excess is responsible for left ventricular (LV) diastolic dysfunction is unknown. Methods and Results: We prospectively enrolled 129 patients with aldosterone‐producing adenoma and 120 patients with essential hypertension, and analyzed their clinical, biochemical, and echocardiographic data, including tissue Doppler images. The patients with aldosterone‐producing adenoma were reevaluated 1 year after adrenalectomy. After propensity score matching, there were 105 patients in each group. The patients with aldosterone‐producing adenoma had worse diastolic function than the patients with essential hypertension, as reflected by lower e′ ( P <0.001) and higher E/e′ ( P =0.003). Multivariate analysis showed that LV diastolic function was significantly correlated with age ( P <0.001), sex ( P <0.001), body mass index ( P =0.002), systolic blood pressure ( P =0.004), creatinine ( P =0.008), and log‐transformed aldosterone‐renin ratio ( P =0.003). After adrenalectomy, the patients with aldosterone‐producing adenoma had significant improvements in LV diastolic function as reflected by an increase in e′ ( P =0.003) and decrease in E/e′ ( P =0.002). The change in E/e′ was independently correlated with baseline E/e′ ( P <0.001) and change in LV mass index ( P =0.006). Conclusions: The patients with primary aldosteronism had worse LV diastolic function than the patients with essential hypertension after propensity score matching, and this could be reversed after adrenalectomy, suggesting that aldosterone excess may induce LV diastolic dysfunction.