Hinokitiol, a Natural Tropolone Derivative, Inhibits TNF-α Production in LPS-Activated Macrophages via Suppression of NF-κB

Abstract

In this study, we examined the modulatory effect of hinokitiol (HK) on the production of tumor necrosis factor (TNF)-α, a critical factor involved in skin inflammation and hair follicle apoptosis. HK effectively suppressed TNF-α production in lipopolysaccharide (LPS)-activated, macrophage-like (RAW264.7) cells. This compound also diminished mRNA synthesis of TNF-α, indicating that HK-mediated inhibition may occur at the transcriptional level. Moreover, this compound down-regulated the phosphorylation of PDK1, Akt/PKB, and ERK, resulting in a loss of nuclear factor (NF)-κB activation, which is detectable by immunoblotting and reporter gene assays. Therefore, these results suggest that HK may cure hair loss by suppressing factors that promote follicular apoptosis, such as TNF-α, in addition to stimulating new hair growth.

Key words

hinokitiol - TNF-α - NF-κB - macrophages - intracellular signaling cascade

References

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