ANTI-INFLAMMATORY EFFECTS OF THE BARK OF PHELLODENDRON AMURENSE RUPR. IN EXPERIMENTAL MODELS

Tóm tắt

The objective of this study was to investigate the anti-inflammatory properties of n-hexane, ethyl acetate (EtOAc), dichloromethane (CH₂Cl₂), and aqueous extracts of Phellodendron amurense. The activity was evaluated in vitro by nitric oxide (NO) and prostaglandin E2 (PGE2) inhibition assays, and in vivo using carrageenan-induced paw edema and lipopolysaccharide (LPS)-induced endotoxemia models in rats. In vitro anti-inflammatory activity was assessed by measuring the inhibition of NO and PGE2 production using RAW 264.7 macrophage cells. Among the tested extracts, the CH₂Cl₂ extract exhibited the most potent activity, with IC₅₀ values of 10.88 ± 2.88 µg/mL for NO inhibition and 10.82 ± 1.22 µg/mL for PGE2 inhibition, followed by the aqueous extract, which also inhibited NO and PGE2 production without causing cytotoxicity. The CH₂Cl₂ extract of P. amurense (CPA) was orally administered to rats in both LPS-induced endotoxemia and carrageenan-induced hind paw edema models. In the endotoxemia model, CPA significantly improved survival and markedly reduced serum IL-6 and IL-1β levels, as well as white blood cell counts. Consistently, in the carrageenan-induced paw edema model, CPA significantly suppressed edema formation, reducing paw-volume increase by 36%, 48%, and 55% at 2, 3, and 4 h, respectively, compared with the carrageenan control group (p < 0.05).