Schisandra chinensisand Its Main Constituent Schizandrin Attenuate Allergic Reactions by Down-Regulating Caspase-1 in Ovalbumin-Sensitized Mice

Schisandra chinensis (SC) and its main constituent, schizandrin (SCH) exhibit anti-inflammatory and anti-allergic activities. Allergic and inflammatory reactions are aggravated via caspase-1 signaling pathway. However, the regulatory effects of SC and SCH on caspase-1 activation have not been clarified yet. In this study, we aimed to clarify the anti-allergic effects of SC and SCH using an ovalbumin (OVA)-sensitized mice and anti-CD3 and anti-CD28 antibodies-stimulated splenocytes. SC or SCH significantly inhibited the levels of immunoglobulin (Ig)E, IgG1, or interleukin (IL)-4 in serum of OVA-sensitized mice. SC or SCH significantly inhibited the levels of IL-6, tumor necrosis factor (TNF)-[Formula: see text], and IL-1[Formula: see text] in spleen of the OVA-sensitized mice. SC or SCH significantly suppressed the expression of caspase-1 and receptor-interacting protein (RIP)-2 in spleen of the OVA-sensitized mice. In activated splenocytes, SC or SCH significantly decreased the expression of caspase-1 and RIP-2 as well as the production of IL-6 and TNF-[Formula: see text]. We suggest that SC and SCH exert an anti-allergic effect by down-regulating caspase-1 signaling.