Selective Azapeptide CD36 Ligand MPE-298 Regulates oxLDL-LOX-1-Mediated Inflammation and Mitochondrial Oxidative...

Area of Science:

• Immunology
• Cell Biology
• Biochemistry

Background:

• Macrophage mitochondrial dysfunction, driven by oxidative stress, is key in chronic inflammatory diseases like atherosclerosis.
• Scavenger receptors CD36 and LOX-1 mediate oxidized low-density lipoprotein (oxLDL) uptake, leading to mitochondrial dysfunction via mtROS production and membrane depolarization.

Purpose of the Study:

• To elucidate the antioxidant mechanisms of the synthetic CD36 ligand MPE-298.
• To investigate MPE-298's effects on oxLDL-induced oxidative stress and inflammation in macrophages.

Main Methods:

• Investigated MPE-298's interaction with CD36 and its internalization via Lyn and Syk tyrosine kinases.
• Assessed MPE-298's impact on oxLDL/LOX-1-induced CCL2 secretion, mtROS production, and mitochondrial membrane potential.
• Examined the inhibition of NADPH oxidase 2 (NOX2) and the recruitment of p47phox and Rac 1/2/3.

Main Results:

• MPE-298 binding induced CD36 endocytosis, inhibiting CCL2 secretion.
• MPE-298 abolished mtROS production and prevented mitochondrial membrane depolarization.
• MPE-298 inhibited oxLDL-activated LOX-1-mediated NOX2 activity by reducing p47phox and Rac recruitment.

Conclusions:

• MPE-298 acts as a CD36 ligand to mitigate oxLDL-induced mitochondrial dysfunction and oxidative stress in macrophages.
• This study reveals a novel mechanism for MPE-298 in combating inflammation via CD36 signaling.
• MPE-298 presents a potential therapeutic agent for inflammatory diseases characterized by macrophage oxidative stress.