S100A8 and psoriasis: Similarly, qPCR analysis showed that RNA expression of psoriasis-related cytokines (Tnfα and Il1β) and psoriasis-related antibacterial peptides (Defb4, S100a7, S100a8, and S100a9) in IL-17-stimulated HaCaT cells was significantly suppressed by limonin in the siControl group, but this suppression was not observed in the siAMPK group (Figure 6e).