Anti-inflammatory activities of Muntingia calabura L. in monosodium urate-induced acute gout arthritis: regulation of NLRP3 and IL-1β

Background: Acute gout arthritis, which is caused by hyperuricemia, is a common inflammatory joint disease, leading to monosodium urate (MSU) crystal deposition. These crystals trigger inflammation, causing pain and significantly impairing the patient’s quality of life. Colchicine is commonly used to treat and prevent acute gout arthritis, but it has several side effects. Cherry tree (Muntingia calabura L.) leaves, which possess anti-inflammatory properties, show promise as an alternative treatment. The potential benefit of the leaves may be due to the flavonoid content. Objectives: This study aimed to assess the anti-inflammatory activities of cherry tree leaves in an MSU-induced acute gout arthritis animal model and to determine the amount of flavonoids. Methods: Cherry tree leaf ethanolic extract (CTLEE) was obtained through maceration using 70% ethanol. Knee circumference, erythema, and levels of NOD-like receptor pyrin domain containing 3 (NLRP3) and interleukin-1 beta (IL-1β) were examined in five animal groups (negative control, positive control, and treatment groups receiving CTLEE at doses of 50, 100, and 200 mg/kg body weight [BW]). The flavonoid content was determined using a colorimetric and gas chromatography-mass spectrometry methods. Results: The groups receiving CTLEE experienced knee circumference recovery and a reduced number of rats with erythema over time. All CTLEE doses significantly reduced NLRP3 and IL-1β levels compared to the negative control at 48- and 72-h post-inductions (P < 0.05). Furthermore, only CTLEE at 50 mg/kg BW could reduce the inflammatory marker levels to the same level of significance as colchicine (P < 0.0001). Conclusion: This is the first report documenting the anti-inflammatory activities of CTLEE in MSU-induced acute gout arthritis animal model, possibly associated with reduced NLRP3 and IL-1ß levels.