Folic acid derived-P5779 mimetics regulate DAMP-mediated inflammation through disruption of HMGB1:TLR4:MD-2 axes

Area of Science:

• Immunology
• Molecular Biology
• Pharmacology

Background:

• High mobility group box 1 (HMGB1) is a key mediator of inflammatory responses, acting as a damage-associated molecular pattern (DAMP).
• A previously identified peptide inhibitor, P5779, blocks HMGB1's inflammatory activity by disrupting its binding to MD-2.

Purpose of the Study:

• To identify novel inhibitors of HMGB1/MD-2 binding.
• To investigate folic acid-derived drugs as potential P5779 mimetopes for anti-inflammatory therapy.

Main Methods:

• Computational methods including fingerprint similarity search and molecular docking studies.
• Molecular dynamic (MD) simulations to analyze binding interactions.
• Surface plasmon resonance (SPR) assays to confirm direct binding.
• In vitro assays using human macrophages to assess inhibition of HMGB1-induced TNF release.

Main Results:

• Folic acid-derived drugs were identified as potential P5779 mimetopes.
• MD simulations confirmed folic acid mimics P5779 binding at the TLR4/MD-2 interface.
• SPR studies showed direct binding of these drugs to TLR4/MD-2, but not HMGB1.
• These mimetopes effectively inhibited HMGB1/MD-2 binding and suppressed HMGB1-induced TNF release in human macrophages at nanomolar concentrations.

Conclusions:

• Folic acid-derived drugs act as functional mimetopes of the HMGB1 inhibitor P5779.
• These compounds exert anti-inflammatory effects by inhibiting HMGB1 binding to TLR4/MD-2.
• The findings suggest a potential therapeutic strategy targeting TLR4-dependent signaling pathways for inflammatory conditions.