12557 Extracellular Vesicles From Patients With Familial Hyperaldosteronism Type-I Modified The Gene Expression Markers Of Endothelial Dysfunction And Inflammation In Human Endothelial Cells: A Preliminary Ex-Vivo Assay

Abstract Disclosure: J.A. Pérez: None. A. Tapia-Castillo: None. A. Martinez: None. P. Carrion: None. M. Hernandez: None. R. Pinilla: None. C.E. Fardella: None. C.A. Carvajal: None. Primary aldosteronism (PA) is caused by aldosterone producing adenoma, bilateral adrenal hyperplasia and genetic forms, including familial hyperaldosteronism type I (FH-I). Patients with FH-I exhibit high levels of aldosterone leading to several arterial hypertension (AHT), left ventricular hypertrophy (LVH) and other cardiovascular manifestations such as endothelial dysfunction, arterial stiffness and inflammation. Aldosterone also has been shown to stimulate the release of extracellular vesicles (EVs). In this regard EVs could act as mediators of the cardiovascular damage observed in FH-I patients. Objective: To evaluate the role ex vivo of circulating EVs from FH-I patients on the gene expression markers of endothelial dysfunction and inflammation in human endothelial cells. Methods: Three patients with FH-I were identified by their clinic, biochemistry and genetic criteria (a positive CYP11B1/CYP11B2 chimeric gene). Circulating EVs from FH-I (FH-I-EVs) were isolated from plasma using ultracentrifugation and further characterized by Nanotraking Analysis (NTA), electron microscopy and western-blot of CD9 and TSG101 proteins. EAhy926 human endothelial cells were incubated with pooled FH-I-EVs (800 EVs/cell) for 24 hours. Subsequently, cells were stimulated with vehicle or 100 nM Aldosterone during the final 6 hours of the incubation with FH-I-EVs. The gene expression of endothelial dysfunction markers such as Endothelin-1 (EDN-1), Intercellular Adhesion Molecule 1 (ICAM-1), Endothelial Nitric Oxide Synthase (NOS3), and inflammation marker Interleukin-1β (IL-1B), were evaluated by RT-qPCR. Statistical analysis was performed by 1-way ANOVA and Tukey post-hoc test using GraphPad Prism v10. Results: FH-I-EVs exhibit a donut shape morphology and the presence of the EVs markers CD9, TSG101 in accordance to the MISEV2023 guidelines. We observed a mean concentration of 2.0 x 109 ± 5.4 x 108 particles/mL and mode size of 105.9 ± 14.2 nm in FH-I-EVs. We observed that pooled FH-I-EVs incubation followed by aldosterone stimulation upregulated the IL-1B (p=0.03), EDN-1 (p=0.02) and ICAM (p<0.001) expression and decreased NOS3 expression (p=0.01) in comparison to aldosterone control in human endothelial cells. Conclusion: Circulating EVs from FH-I patients in presence of aldosterone, modify the expression of endothelial disfunction markers (EDN-1, ICAM and NOS3) and upregulate the expression of the inflammation marker IL-1B in human endothelial cells. These findings suggest that in FH-I patients, their circulating EVs and high aldosterone concentrations, have a synergistic effect on endothelial function and inflammatory status of endothelial cells. Acknowledgment: SOCHED, CETREN UC, ANID-FONDECYT 1212006 AND 3200646, CONICYT-FONDEQUIP EQM150023. Presentation: 6/3/2024