Treating rheumatoid arthritis using fibroblast-activated protein-α-responsive micelles through a cascade control...

Area of Science:

• Biomedical Engineering
• Immunology
• Pharmacology

Background:

• Rheumatoid arthritis (RA) is a chronic autoimmune disease impacting joints, necessitating improved therapies beyond conventional glucocorticoids due to toxicity and limited efficacy.
• Dexamethasone (Dex) is a common glucocorticoid but causes systemic side effects and has variable efficacy in RA treatment.

Purpose of the Study:

• To develop and evaluate novel LMWH-Gly-Pro-ODA/Dex (LGPO/Dex) micelles for targeted and responsive rheumatoid arthritis treatment.
• To investigate the synergistic potential of low molecular weight heparin (LMWH) active targeting and fibroblast-activated protein-alpha (FAP-α)-responsive drug release for precise RA therapy.

Main Methods:

• Construction of LGPO/Dex micelles integrating LMWH for active targeting and Gly-Pro for FAP-α-responsive release of dexamethasone.
• Evaluation of the three-stage cascade mechanism: joint targeting, inflammation-responsive release, and monocyte recruitment suppression.
• Assessment of therapeutic efficacy in an adjuvant-induced arthritis (AIA) rat model, measuring joint swelling, serum TNF-α, and nitric oxide (NO) levels.

Main Results:

• LGPO/Dex micelles demonstrated significant therapeutic effects in the AIA model, normalizing joint swelling and inflammatory markers (TNF-α, NO) to levels comparable to healthy controls.
• Treatment with LGPO/Dex micelles showed marked improvement over dexamethasone monotherapy.
• The novel micelles significantly reduced dexamethasone-associated adverse effects.

Conclusions:

• Fibroblast-activated protein-alpha (FAP-α) is a feasible therapeutic target for rheumatoid arthritis.
• The developed LGPO/Dex micelle system offers a promising strategy for precise, disease-microenvironment-programmed RA therapeutics with reduced toxicity.