Water extract isolated from Chelidonium majus enhances nitric oxide and tumour necrosis factor-α production via nuclear factor-κB activation in mouse peritoneal macrophages

Chelidonium majus is used to treat several inflammatory diseases and tumours. We have examined the effect of C. majus on nitric oxide (NO) production using mouse peritoneal macrophages. When C majus was used in combination with recombinant interferon-γ (rIFN-γ, 10 U mL^-1), there was a marked cooperative induction of NO production. Treatment of rIFN-γ plus C. majus (1 mg mL^-1) in macrophages caused a significant increase in tumour necrosis factor-α (TNF-α) production. The increased production of NO and TNF-α from rIFN-γ plus C. majus-stimulated cells was almost completely inhibited by nuclear factor-κB (NF-κB) inhibitor, pyrrolidine dithiocarbamate (100 μM). These findings demonstrated that C. majus increased the production of NO and TNF-α by rIFN-γ-primed macrophages and suggested that NF-κB played a critical role in mediating the effects of C. majus.