Herbal extracts that induce type I interferons through Toll-like receptor 4 signaling

Background: A mixture of five herbal extracts called internatural (INT), which is prepared from pumpkin seeds, purple turmeric, pearl barley, corn pistil, and cinnamon, is widely used by people in Japan and elsewhere for its immunity-enhancing effects and general health. Although anecdotal evidence indicates its efficacy, the mechanisms by which INT boosts immunity have remained unknown. Objective: The aim of this study was to investigate whether INT induces type I interferons (IFNs) in murine...