GENETIC AND PHARMACOLOGIC ACTIVATION OF BECLIN1 PREVENTS ALDOSTERONE-INDUCED CARDIOVASCULAR DAMAGE

Rafael M Costa1,2, Ariane Bruder1, Juliano V Alves2

  • 1Department of Physiology and Cell Biology, University of South Alabama, Mobile, AL, United State of America.

Insights

Aldosterone impairs vascular function by disrupting autophagy. Enhancing autophagy through Beclin1 (BCN1) activation protects against aldosterone-induced endothelial dysfunction and cardiovascular injury.

Area of Science:

  • Cardiovascular Biology
  • Cellular Biology
  • Molecular Medicine

Background:

  • Aldosterone promotes cardiovascular injury via mineralocorticoid receptor (MR) activation.
  • Autophagy is crucial for endothelial homeostasis, but its role in aldosterone-induced vascular dysfunction is unknown.
  • This study investigates aldosterone's effect on autophagic flux and the protective potential of Beclin1 (BCN1) activation.

Purpose of the Study:

  • To determine if aldosterone impairs autophagic flux.
  • To investigate if restoring autophagy via Beclin1 (BCN1) activation protects vascular and cardiac function.
  • To explore therapeutic strategies for cardiovascular diseases linked to mineralocorticoid excess.

Main Methods:

  • Assessed endothelial and vascular responses in wild-type, BCN1 gain-of-function mice, and mice treated with spermidine or a BCN1-activating TB-peptide.
  • Evaluated vascular function, nitric oxide (NO)/reactive oxygen species (ROS) production, autophagy markers, endothelial migration, and cardiac fibrosis.
  • Utilized wire myography, fluorescence assays, Western blotting, confocal microscopy, migration assays, and histology.

Main Results:

  • Aldosterone impaired endothelium-dependent relaxation, decreased NO, increased ROS, and disrupted autophagic flux in an MR-dependent manner.
  • Spermidine and BCN1 gain-of-function restored endothelial function and normalized NO/ROS levels.
  • BCN1 activation protected against aldosterone-induced endothelial dysfunction, reduced cardiac fibrosis, and rescued endothelial migration.

Conclusions:

  • Aldosterone induces endothelial dysfunction by suppressing autophagic flux via MR activation.
  • Enhancing BCN1-dependent autophagy restores endothelial homeostasis and prevents cardiovascular injury.
  • Autophagy activation is a potential therapeutic target for mineralocorticoid excess-related cardiovascular diseases.
Abstract

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