Paeonol inhibited TNFα-induced GM-CSF expression in fibroblast-like synoviocytes

Area of Science:

• Immunology and Inflammation Research
• Molecular Biology and Signaling Pathways
• Rheumatology and Autoimmune Diseases

Background:

• Granulocyte macrophage colony-stimulating factor (GM-CSF) is a key chemokine in rheumatoid arthritis (RA).
• The precise regulatory mechanisms of GM-CSF in RA pathogenesis remain incompletely understood.
• Fibroblast-like synoviocytes (FLS) are critical cellular components in RA joint inflammation.

Purpose of the Study:

• To investigate the effect of paeonol on GM-CSF expression in FLS.
• To elucidate the molecular pathways involved in paeonol's regulation of GM-CSF.
• To assess paeonol's impact on TNF-α-induced FLS proliferation.

Main Methods:

• GM-CSF expression (protein and mRNA) was measured in FLS stimulated with TNF-α, with and without paeonol pre-treatment.
• Western blotting was used to detect phosphorylation of PI3K/Akt and expression of NF-κB and p-I-κB-α.
• Specific pathway inhibitors (LY294002, perifosine, BAY11-7082, SC-514) were employed to confirm mechanistic roles.

Main Results:

• TNF-α significantly upregulated GM-CSF in FLS in a dose- and time-dependent manner.
• Paeonol treatment markedly suppressed TNF-α-induced GM-CSF production.
• Paeonol inhibited TNF-α-mediated phosphorylation of PI3K/Akt and activation of the NF-κB pathway, confirming its mechanism of action.

Conclusions:

• Paeonol effectively inhibits TNF-α-induced GM-CSF production in FLS.
• The PI3K/Akt/NF-κB signaling pathway is crucial for GM-CSF regulation by paeonol.
• Paeonol demonstrates potential as a therapeutic agent for RA by modulating key inflammatory mediators.