Podocyte-Derived Extracellular Vesicles Induce Endothelial Dysfunction by Triggering ER Stress in Glomerular Disease

Area of Science:

• Nephrology
• Cell Biology
• Molecular Medicine

Background:

• Glomerular disease is characterized by podocyte injury and endothelial cell dysfunction, but the link between them is unclear.
• Extracellular vesicles (EVs) are increasingly recognized as mediators of intercellular communication.
• Understanding podocyte-endothelial crosstalk via EVs is crucial for deciphering glomerular disease pathogenesis.

Purpose of the Study:

• To investigate the role of podocyte-derived EVs in mediating communication with endothelial cells during glomerular disease.
• To identify specific molecular mechanisms involved in EV-mediated podocyte-endothelial interactions.
• To explore potential therapeutic strategies targeting EV pathways in glomerular disease.

Main Methods:

• Characterization of podocyte-derived EVs using nanoparticle tracking analysis and electron microscopy.
• Proteomic analysis to identify proteins within EVs, focusing on integrin αvβ1, focal adhesion kinase (FAK), and endoplasmic reticulum (ER) stress markers.
• In vitro and in vivo experiments using siRNA, neutralizing antibodies, and small molecule inhibitors to assess the functional impact of integrin αvβ1 and EV secretion.

Main Results:

• Podocyte injury increased the secretion of EVs enriched with integrin αvβ1.
• Podocyte EVs were taken up by endothelial cells, leading to integrin αvβ1 transfer, FAK activation, ER stress, and apoptosis.
• Inhibition of EV secretion or integrin β1 signaling ameliorated endothelial dysfunction and glomerulosclerosis in mouse models.

Conclusions:

• Podocyte injury induces endothelial dysfunction through the release of integrin αvβ1-enriched EVs.
• These EVs activate FAK-mediated ER stress and apoptosis in endothelial cells.
• Targeting EV secretion or integrin αvβ1 signaling represents a potential therapeutic approach for glomerular diseases.