SA4503 Mitigates Adriamycin-Induced Nephropathy via Sigma-1 Receptor in Animal and Cell-Based Models

Area of Science:

• Nephrology
• Molecular Biology
• Pharmacology

Background:

• The Sigma-1 receptor (Sigmar1) is an intracellular chaperone protein with an unclear role in kidney function.
• Adriamycin (ADR) is known to induce renal glomerular injury.

Purpose of the Study:

• To investigate the protective effects of SA4503, a selective Sigmar1 agonist, on Adriamycin (ADR)-induced renal glomerular injury.
• To elucidate the molecular mechanisms underlying SA4503's protective actions.

Main Methods:

• Utilized in vitro and in vivo models to assess ADR-induced podocyte injury.
• Evaluated podocyte survival, albumin permeability, and urinary albumin levels.
• Investigated Sigmar1-nephrin interactions and used a Sigmar1 antagonist (NE-100) to confirm specificity.

Main Results:

• Sigmar1 is highly expressed in podocytes and kidney tissues.
• SA4503 significantly reduced ADR-induced podocyte injury and urinary albumin leakage in mice.
• SA4503 preserved Sigmar1-nephrin interactions, and this effect was blocked by NE-100.

Conclusions:

• Activation of Sigmar1 by SA4503 protects against ADR-induced podocyte injury and glomerular damage.
• Stabilization of Sigmar1-nephrin interactions is a key mechanism of SA4503's protective effect.
• Sigmar1 is a promising therapeutic target for glomerular diseases, including nephrotic syndrome.