Excessive release of proinflammatory cytokines mediates the toxic effect of superantigenic staphylococcal exotoxins (SE). Baicalin, a flavone isolated from the Chinese herb Scutellaria baicalensis Georgi and used in China to treat infectious diseases, inhibited SE-stimulated T-cell proliferation (by 98%) and production of interleukin 1β, interleukin 6, tumor necrosis factor, interferon γ, monocyte chemotactic protein 1, macrophage inflammatory protein (MIP)-1α, and MIP-1β mRNA and protein by human peripheral blood mononuclear cells. These data suggest that baicalin may be therapeutically useful for mitigating the pathogenic effects of SE by inhibiting the signaling pathways activated by superantigens.
