CASP1 and serum lipopolysaccharide activity: Similar to shikonin9, repetitive administration of C16 at −0.5, +12 and +24 h following the onset of endotoxemia (5 mg kg−1 LPS, i.p.)conferred significant protection against lethality (Fig. 6c) and reduced EIF2AK2 phosphorylation (Fig. 6a), and caspase-1 activity (Fig. 6b) in PMs.