Methanol extract of Cordyceps pruinosa inhibits in vitro and in vivo inflammatory mediators by suppressing NF-κB activation

Cordyceps pruinosa has been used in traditional folk medicine to treat numerous diseases. The molecular mechanism of C. pruinosa pharmacological and biochemical actions of macrophages in inflammation has not been clearly elucidated. We examined how the methanol extract of C. pruinosa regulates production of IL-1β, TNF-α, nitric oxide (NO), and prostaglandin E₂ (PGE₂) in vitro and in vivo. The extract inhibits these inflammatory mediators in LPS-stimulated murine macrophage cell line RAW264.7 and primary macrophages, by suppressing gene expression of IL-1β, TNF-α, inducible nitric oxide synthase, and cyclooxygenase-2. Moreover, the extract suppresses the nuclear transcription factor NF-κB activation in LPS-stimulated RAW264.7 cells. Administration of the extract significantly decreases the plasma levels of these inflammatory mediators in LPS-injected mice. These results suggest that the C. pruinosa methanol extract suppresses inflammation through suppression of NF-κB-dependent inflammatory gene expression, suggesting that the C. pruinosa extract may be beneficial for treatment of endotoxin shock or sepsis.