Targeted inhibition of M2 macrophages polarization via a PDC attenuates chronic pancreatitis through the PPARα...

Area of Science:

• Immunology
• Gastroenterology
• Pharmacology

Background:

• M2-type macrophages play a key role in chronic pancreatitis (CP) pathogenesis.
• Targeted intervention for M2 macrophages in CP faces significant challenges.
• Developing effective immunomodulatory therapies for CP is crucial.

Purpose of the Study:

• To investigate the role of M2 macrophages in CP.
• To develop and evaluate a novel peptide-drug conjugate (PDC) for targeted M2 macrophage intervention.
• To elucidate the mechanism of action of the PDC in CP models.

Main Methods:

• Development of a PDC by conjugating the S100A9 inhibitor Tasquinimod to an M2 macrophage-targeting peptide.
• Evaluation of the PDC's efficacy in experimental CP models.
• Assessment of pancreatic injury, inflammation, fibrotic progression, and organ toxicity.
• Mechanistic studies involving the peroxisome proliferator-activated receptor α (PPARα) and NF-κB signaling pathways.

Main Results:

• The developed PDC significantly alleviated pancreatic injury, inflammation, and fibrosis in experimental models.
• The PDC exhibited enhanced M2 macrophage targeting, superior efficacy, and a reduced toxicity profile compared to the free drug.
• Mechanistic analysis revealed that the PDC activates PPARα signaling, suppressing NF-κB and c-Jun phosphorylation, thereby inhibiting M2 macrophage polarization.

Conclusions:

• The study successfully developed a targeted PDC for M2 macrophages, demonstrating significant therapeutic potential in CP.
• The PDC's mechanism involves the PPARα pathway, offering a novel immunomodulatory approach for CP treatment.
• These findings provide a strong foundation for developing targeted immunotherapies against chronic pancreatitis.