alpha-chaconine and Inflammation

In this study, we investigated the molecular mechanisms underlying the anti-inflammatory effects of α-chaconine in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages and in LPS-induced septic mice. α-Chaconine inhibited the expressions of cyclooxygenase-2 (COX-2), interleukin-1β (IL-1β), IL-6, and tumor necrosis factor-α (TNF-α) at the transcriptional level, and attenuated the transcriptional activity of activator protein-1 (AP-1) by reducing the translocation and phosphorylation of c-Jun. α-Chaconine also suppressed the phosphorylation of TGF-β-activated kinase-1 (TAK1), which lies upstream of mitogen-activated protein kinase kinase 7 (MKK7)/Jun N-terminal kinase (JNK) signaling. JNK knockdown using siRNA prevented the α-chaconine-mediated inhibition of pro-inflammatory mediators. In a sepsis model, pretreatment with α-chaconine reduced the LPS-induced lethality and the mRNA and production levels of pro-inflammatory mediators by inhibiting c-Jun activation. These results suggest that the anti-inflammatory effects of α-chaconine are associated with the suppression of AP-1, and support its possible therapeutic role for the treatment of sepsis.

Topics: Animals; Cell Line; Cyclooxygenase 2; Endotoxins; Inflammation; Interleukin-1beta; Interleukin-6; Lipopolysaccharides; Macrophages; Male; MAP Kinase Kinase 4; MAP Kinase Kinase 7; Mice; Mice, Inbred C57BL; Phosphorylation; Solanine; Solanum tuberosum; Transcription Factor AP-1; Transforming Growth Factor beta; Tumor Necrosis Factor-alpha