Popis: |
Background: Triptonide (TPN) is a major component of Tripterygium wilfordii Hook.f., and reportedly has anti-inflammatory and neuroprotective effects. Recent studies have demonstrated that the phosphatidylinositol 3-kinase (PI3K)/AKT pathway plays an important role in the pathogenesis of inflammatory pain. Here we investigated the anti-nociceptive effect of systemic treatment with TPN on mouse models of chronic inflammatory pain and explored possible mechanisms. Results: Unilateral hind paw injection of complete Freund’s adjuvant (CFA) induced paw edema and persistent pain hypersensitivity. Intravenous treatment with TPN attenuated CFA-induced paw edema, mechanical allodynia, and thermal hyperalgesia. Western blotting and immunofluorescence results showed that CFA induced AKT activation in the dorsal root ganglion (DRG) neurons, which was inhibited by TPN treatment. Furthermore, TPN treatment inhibited mRNA increase of proinflammatory cytokines [tumor necrosis factor-α (TNF-α), interleukin 1 beta (IL-1β), and Interleukin 6 (IL-6)] induced by CFA. Finally, pretreatment with AKT inhibitor, AKT inhibitor Ⅳ, attenuated CFA-induced mechanical allodynia and thermal hyperalgesia, and decreased the mRNA expression of pro-inflammatory cytokines. Conclusions: These data indicate that TPN attenuates CFA-induced pain potentially via inhibiting AKT-mediated pro-inflammatory cytokines production in DRG. TPN may be used for the treatment of chronic inflammatory pain. |