Effect of Indirubin on Morphology Changes and mRNA Expression of Cytokines in LPS-induced RAW264.7

This study was conducted to investigate the regulatory effect of Indirubin on LPS-induced inflammation in macrophage. The morphologic changes were shown as widened cytoplasm or biased nucleus from the center of the cell when LPS activated macrophage. The changes in inflammation activity were also estimated with mRNA levels of cytokines under time elapse at 2, 4, 8, 12, and 24 hours after the 10 ng/mL LPS treatment. By measuring those proinflammatory (TNF-α, IL-1β) and anti-inflammatory (IL-10) cytokines at each time set, the relationship between morphologic change and inflammation activity was compared. The highest pro-inflammatory mRNA expression was observed at 2 hours after the LPS treatment, and this was inhibited by those Indirubin standard (Indirubin) and Chungdae extract (CDEX). The mRNA expression level in LPS treated cell was markedly reduced at 8 hours as well as the other groups. However, IL-10, the anti-inflammatory cytokines was not affected by those treatments. The results suggested that the level of inflammation related changes as time elapsed. The current observation that both Indirubin and CDEX are able to inhibit LPS-induced inflammation by reducing the production of inflammatory cytokines. Moreover, the current observation suggested that estimating anti-inflammatory effects should include time-dependent measurements as biomarkers.