Diterpenoids of Tripterygium wilfordii decrease inflammatory response of macrophage by inhibiting multiple signaling pathways / 中国药理学通报

ABSTRACT

Aim To study the anti-inflammatory activ¬ity of diterpenes from Tripterygium wilfordii on lipopo- lysaccharide ( LPS)-induced macrophage and its mech¬anism. Methods MTT assay was used to detect the cytotoxicity of compounds. The Griess method was used to detect the NO on LPS-induced RAW264. 7 cells. ELISA was applied to determine the contents of inter- leukin 6 (IL-6) , tumor necrosis factor a ( TNF-a ) , interleukin lp (IL-lfj) and interleukin 18 (IL-18) in cell culture supernatant. Western blot was used to de¬tect IkBcx, .INK, ERK, p38, STAT3 and their phos-phorylation in LPS-induced RAW264.7, as well as the effect on COX-2, iNOS, NLRP3, caspase-1 , cleaved- caspase-1. Flow cytometry was employed to detect the effects of compounds on the phagocytosis of RAW 264. 7 cells. Results Hypoglicin II (1) and ent-pimara-8 (14) , 15-diene-19-ol (6) , two diterpenoid compounds from Tripterygium wilfordii could effectively inhibit the expression of inflammatory mediators ( COX-2 and iN- OS) and inflammatory cytokines (IL-6, IL-lp, IL- 18) in LPS-induced RAW264. 7 cells. Further re¬search found that the phosphorylation of IkBcx , JNK, ERK, P38, STAT3 and NLRP3 was all inhibited; however, there was no significant effect on the expres¬sion of IkBcx, JNK, ERK, P38 and STAT3. At the same time, they also inhibited the phagocytosis of mac-rophages. Conclusions The anti-inflammatory mecha¬nism of Tripterygium wilfordii diterpenoids 1 and 6 might be through inhibiting the production of NLRP3 inflammatory bodies, inflammatory mediators (COX-2 and iNOS) and inflammatory cytokines (IL-6, IL-lp and IL-18) , which is closely related to inhibiting the activation of MAPK, NF-kB and STAT3 pathway.