Phellodendrine chloride alleviates gouty arthritis through IL-6/STAT3 signaling pathway

Phellodendrine, a primary bioactive constituent of Phellodendron chinense Schneid (PCS), is crucial in its pharmacological profile. Phellodendrine exhibits potent anti-nephritic properties and demonstrates a marked inhibitory effect on the cellular immune response. However, the effects of phellodendrine on proteoglycan depletion and cartilage degeneration in gouty arthritis remain insufficiently understood. Therefore, the objective of this study is to elucidate the therapeutic potential and underlying mechanisms of phellodendrine chloride (PC) in the treatment of gouty arthritis.

A monosodium urate (MSU)-induced arthritis model in rats, along with a peritonitis model in mice, was developed, in combination with a chondrocyte model. Neutrophil proportions were quantified using flow cytometry. The expression levels of MMP-3, STAT3, and phosphorylated STAT3 (p-STAT3) in chondrocytes were determined by Western blot analysis. Proteoglycan levels in chondrocytes were assessed using toluidine blue staining and quantitative reverse transcription PCR (qRT-PCR). Joint swelling rates were monitored at 0-24 h in rats, and histopathological changes in joint tissues were subsequently analyzed.

Phellodendrine chloride mitigated the rise in neutrophil proportions within MSU-induced peritoneal lavage fluid in mice and decreased inflammatory cell infiltration in rat ankle tissues. Treatment with phellodendrine chloride led to a downregulation of MMP-3 protein levels and inhibited IL-1β-induced proteoglycan degradation in chondrocytes. Additionally, results from experiments combining IL-1β with AG490 or IL-6 demonstrated that phellodendrine chloride attenuated IL-1β-induced MMP-3 expression and proteoglycan degradation.

Our findings suggest that phellodendrine chloride mitigates gouty arthritis (GA) by modulating the IL-6/STAT3 signaling pathway.