Aldosterone excess plays a major role in the progression of cardiac dysfunction and remodeling in clinical diseases such as primary aldosteronism and heart failure. However, the effect of aldosterone excess on cardiac mitochondria is unclear. In this study, we investigated the effect of aldosterone excess on cardiac mitochondrial dysfunction and its mechanisms in vitro and in vivo. We used H9c2 cardiomyocytes to investigate the effect and mechanism of aldosterone excess on cardiac mitochondria, and further investigated them in an aldosterone-infused ICR mice model. The results of the cell study showed that aldosterone excess decreased mitochondrial DNA, COX IV and SOD2 protein expressions, and mitochondria ATP production. These effects were abolished or attenuated by treatment with a mineralocorticoid receptor (MR) antagonist and antioxidant. With regard to the signal transduction pathway, aldosterone suppressed cardiac mitochondria through an MR/MAPK/p38/reactive oxygen species pathway. In the mouse model, aldosterone infusion decreased the amount of cardiac mitochondrial DNA and COX IV protein, and the effects were also attenuated by treatment with an MR antagonist and antioxidant. In conclusion, aldosterone excess induced a decrease in mitochondria and mitochondrial dysfunction via MRs and oxidative stress in vitro and in vivo.
Excessive aldosterone secretion causes endothelial dysfunction, vascular inflammation, and vascular fibrosis in patients with primary aldosteronism (PA). Endothelial function is closely related to endothelial mitochondria. However, the effects of elevated aldosterone levels on endothelial mitochondria remain unclear. In this study, we used primary cultured human umbilical vein endothelial cells (HUVECs) to investigate the effects of aldosterone on endothelial mitochondria. Mineralocorticoid receptor (MR) small interfering (si)RNA or glucocorticoid receptor (GR) siRNA were used to confirm the pathway by which aldosterone exerts its effects on the mitochondria of HUVECs. The results showed that excess aldosterone suppressed mitochondrial DNA copy numbers, anti-mitochondrial protein, and SOD2 protein expression in a dose- and time-dependent manner. These effects were attenuated by treatment with MR siRNA, but not with GR siRNA. Furthermore, it was attenuated by treatment with a mitochondria-targeted antioxidant (Mito-TEMPO, associated with mitochondrial reactive oxygen species (ROS) production), but not N-acetyl-L-cysteine (associated with cytosolic ROS production), which suggests that the process was through the mitochondrial ROS pathway, but not the cytosolic ROS pathway. In conclusion, aldosterone excess suppressed endothelial mitochondria through the MR/mitochondrial ROS pathway.
Background: Mesenchymal stem cells (MSCs) hold promise for cell-based therapy, yet the sourcing, quality, and invasive methods of MSCs impede their mass production and quality control. Induced pluripotent stem cell (iPSC)-derived MSCs (iMSCs) can be infinitely expanded, providing advantages over conventional MSCs in terms of meeting unmet clinical demands. Methods: The potential of MSC therapy for Leber’s hereditary optic neuropathy (LHON) remains uncertain. In this study, we used HLA-homozygous induced pluripotent stem cells to generate iMSCs using a defined protocol, and we examined their therapeutic potential in rotenone-induced LHON-like models in vitro and in vivo. Results: The iMSCs did not cause any tumorigenic incidence or inflammation-related lesions after intravitreal transplantation, and they remained viable for at least nine days in the mouse recipient’s eyes. In addition, iMSCs exhibited significant efficacy in safeguarding retinal ganglion cells (RGCs) from rotenone-induced cytotoxicity in vitro, and they ameliorated CGL+IPL layer thinning and RGC loss in vivo. Optical coherence tomography (OCT) and an electroretinogram demonstrated that iMSCs not only prevented RGC loss and impairments to the retinal architecture, but they also improved retinal electrophysiology performance. Conclusion: The generation of iMSCs via the HLA homozygosity of iPSCs offers a compelling avenue for overcoming the current limitations of MSC-based therapies. The results underscore the potential of iMSCs when addressing retinal disorders, and they highlight their clinical significance, offering renewed hope for individuals affected by LHON and other inherited retinal conditions.
Primary aldosteronism is the most common form of secondary hypertension and induces various cardiovascular injuries. In aldosterone-producing adenoma (APA), the impact of KCNJ5 somatic mutations on arterial stiffness excluding the influence of confounding factors is uncertain. We enrolled 213 APA patients who were scheduled to undergo adrenalectomy. KCNJ5 gene sequencing of APA was performed. After propensity score matching (PSM) for age, sex, body mass index, blood pressure, number of hypertensive medications, and hypertension duration, there were 66 patients in each group with and without KCNJ5 mutations. The mutation carriers had a higher aldosterone level and lower log transformed brachial–ankle pulse wave velocity (baPWV) than the non-carriers before PSM, but no difference in log baPWV after PSM. One year after adrenalectomy, the mutation carriers had greater decreases in log plasma aldosterone concentration, log aldosterone–renin activity ratio, and log baPWV than the non-carriers after PSM. Only the mutation carriers had a significant decrease in log baPWV after surgery both before and after PSM. KCNJ5 mutations were not correlated with baseline baPWV after PSM but were significantly correlated with ∆baPWV after surgery both before and after PSM. Conclusively, APA patients with KCNJ5 mutations had a greater regression in arterial stiffness after adrenalectomy than those without mutations.
About Me
National Taiwan University
No. 1, Sec. 4, Roosevelt Rd., Taipei 10617, Taiwan (R.O.C.)
National Taiwan University
No. 1, Sec. 4, Roosevelt Rd., Taipei 10617, Taiwan (R.O.C.)