An investigation into the efficacy and mechanism of Berchemia kulingensis leaves in suppressing synovial tissue inflammation in a rat model of gouty arthritis.

The pharmacological activities of Berchemia kulingensis (BK) leaves, traditionally used as a tea for joint discomfort relief in Chinese folk, remain unexplored. To explore the potential therapeutic effects of BK-leaves on gouty arthritis (GA), thus providing a scientific basis for their folk use and pharmaceutical development. The secondary metabolites of BK-leaves were analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) technology. Combined with activity prediction, the therapeutic potential and related mechanisms of action were further systematically explored through GA rat models and in vitro cell models. The prediction of the identified compounds' biological activity suggests BK leaves may have potential therapeutic effects on GA. Animal experiments show that extract of BK-leaves alleviated synovial inflammation in rats, reduced the concentrations of tumor necrosis factor (TNF)-α, interleukin-1β (IL-1β), IL-6, IL-8, cyclooxygenase (COX)-2, and matrix metalloproteinase (MMP)-9, inhibited protein expression of NLR family pyrin domain-containing protein 3 (NLRP3) and Toll-like receptor 4 (TLR4), as well as phosphorylation of proteins including p65 subunit of nuclear factor (NF)-κB, NF-κB inhibitor kinase (IKK) alpha/beta, and signal transducer and activator of transcription 3 (STAT3), while simultaneously upregulated protein expression of the nuclear factor κB inhibitor alpha (IκBα) (P < 0.05, P < 0.01, or P < 0.001). Additionally, BK-leaf extract inhibited xanthine oxidase (XO) activity in vitro (P < 0.05, 0.01, or 0.001). BK-leaf has potential therapeutic value for GA, and its mechanism may be related to regulating the TLR4-NF-κB signaling pathway and inhibiting XO activity.