Suppression of thymus- and activation-regulated chemokine (TARC/CCL17) production by 3-O-β-D-glucopyanosylspinasterol via blocking NF-κB and STAT1 signaling pathways in TNF-α and IFN-γ-induced HaCaT keratinocytes.

A phytosterol derivative, 3-O-β-D-glucopyanosylspinasterol (spinasterol-Glc) isolated from leaves of Stewartia koreana was reported to inhibit LPS-induced cytokine production in macrophage cells. Thymus and activation regulated chemokine (TARC/CCL17) is produced in response to pro-inflammatory cytokines in keratinocytes, which is implicated in the development of inflammatory skin diseases. In present study, we investigated the effect of spinasterol-Glc on production of TARC/CCL17 induced by TNF-α and IFN-γ in human HaCaT keratinocytes. Spinasterol-Glc inhibited the mRNA and protein expression of TARC/CCL17 induced by TNF-α/IFN-γ in a dose-dependent manner. Inhibitors of c-Raf-1, p38 MAPK, and JAK2, suppressed the TNF-α/IFN-γ-induced production of TARC/CCL17, and phosphorylation of these signaling molecules were attenuated by spinasterol-Glc. The compound also inhibited phosphorylation of IKKα/β and IκB-α, and reduced translocation of NF-κB to the nucleus. We demonstrated that spinasterol-Glc suppressed the NF-κB-driven and the GAS-driven expression of luciferase reporter gene induced by TNF-α and IFN-γ. In addition, spinasterol-Glc inhibited the DNA binding of NF-κB and STAT1 to its cognate binding site. These results suggest that spinasterol-Glc has effective inhibitory effects on production of TARC/CCL17 in keratinocytes via inhibition of NF-κB as well as STAT activation, and could be utilized for development of a potential therapeutic agent against skin inflammatory diseases.

Jung MR ，Lee TH ，Bang MH ，Kim H ，Son Y ，Chung DK ，Kim J ... -  《-》

Casuarinin suppresses TARC/CCL17 and MDC/CCL22 production via blockade of NF-κB and STAT1 activation in HaCaT cells.

Casuarinin is a naturally occurring tannin that is isolated from the leaves of Hippophae rhamnoides. It has been shown to have anti-oxidant, anti-cancer, anti-viral, and anti-inflammatory activities. The aim of this study was to investigate the possible mechanism by which casuarinin inhibits TNF-α/IFN-γ-induced Th2 chemokines expression in the human keratinocytes cell line HaCaT. We found that casuarinin suppressed TNF-α/IFN-γ-induced expression of TARC and MDC mRNA and protein in HaCaT cells. Casuarinin significantly inhibited TNF-α/IFN-γ-induced activation of NF-κB, STAT1, and p38 MAPK. Furthermore, we observed that p38 MAPK contributes to inhibition of TNF-α/IFN-γ-induced TARC and MDC production by blocking NF-κB and STAT1 activation in HaCaT cells. Taken together, these results suggest that casuarinin may exert anti-inflammatory responses by suppressing TNF-α/IFN-γ-induced expression of TARC and MDC via blockage of p38 MAPK activation and subsequent activation of NF-κB and STAT1. We propose that it could therefore be used as a therapeutic agent against inflammatory skin diseases.

Kwon DJ ，Bae YS ，Ju SM ，Goh AR ，Youn GS ，Choi SY ，Park J ... -  《-》

Ginsenoside Rg5:Rk1 attenuates TNF-α/IFN-γ-induced production of thymus- and activation-regulated chemokine (TARC/CCL17) and LPS-induced NO production via downregulation of NF-κB/p38 MAPK/STAT1 signaling in human keratinocytes and macrophages.

Ahn S ，Siddiqi MH ，Aceituno VC ，Simu SY ，Zhang J ，Jimenez Perez ZE ，Kim YJ ，Yang DC ... -  《-》

(+)-Nootkatone inhibits tumor necrosis factor α/interferon γ-induced production of chemokines in HaCaT cells.

Chemokines are important mediators of cell migration, and thymus and activation-regulated chemokine (TARC/CCL17) and macrophage-derived chemokine (MDC/CCL22) are well-known typical inflammatory chemokines involved in atopic dermatitis (AD). (+)-Nootkatone is the major component of Cyperus rotundus. (+)-Nootkatone has antiallergic, anti-inflammatory, and antiplatelet activities. The purpose of this study was to investigate the effect of (+)-nootkatone on tumor necrosis factor α (TNF-α)/interferon γ (IFN-γ)-induced expression of Th2 chemokines in HaCaT cells. We found that (+)-nootkatone inhibited the TNF-α/IFN-γ-induced expression of TARC/CCL17 and MDC/CCL22 mRNA in HaCaT cells. It also significantly inhibited TNF-α/IFN-γ-induced activation of nuclear factor kappa B (NF-κB), p38 mitogen-activated protein kinase (MAPK), and protein kinase Cζ (PKCζ). Furthermore, we showed that PKCζ and p38 MAPK contributed to the inhibition of TNF-α/IFN-γ-induced TARC/CCL17 and MDC/CCL22 expression by blocking IκBα degradation in HaCaT cells. Taken together, these results suggest that (+)-nootkatone may suppress TNF-α/IFN-γ-induced TARC/CCL17 and MDC/CCL22 expression in HaCaT cells by inhibiting of PKCζ and p38 MAPK signaling pathways that lead to activation of NF-κB. We propose that (+)-nootkatone may be a useful therapeutic candidate for inflammatory skin diseases such as AD.

Choi HJ ，Lee JH ，Jung YS 《-》

Inhibitory effect of 5,6-dihydroergosteol-glucoside on atopic dermatitis-like skin lesions via suppression of NF-κB and STAT activation.

Atopic dermatitis (AD) is a Th2-type disease. Keratinocytes, a major type in the skin, produce Th2 chemokines such as thymus and activation-regulated chemokine (TARC)/CCL17 and macrophage-derived chemokine (MDC)/CCL22, which play pivotal roles in the development of Th2-dominant inflammatory skin diseases. Recently, it was reported that 5,6-dihydroergosterol-glucoside (DHE-Glc) was synthesized and exhibited strong anti-inflammatory activity. We aimed to investigate the effects of DHE-Glc, a synthetic molecule derived from ergosterol, on AD-like skin lesions induced by 2,4-dinitrochlorobenzene (DNCB) in mice and to elucidate the effects of DHE-Glc on TNF-α/IFN-γ-induced production of CCL17 and CCL22 in human keratinocytes (HaCaTs) and DNCB induced skin inflammation mice model. Mice were sensitized and challenged on the skin of their backs with DNCB. At 30-60 days after sensitization, mice were treated with cutaneous administration of DHE-Glc by skin smear. HaCaT cells were used to evaluate the effects of DHE-Glc on production of CCL17 and CCL22 and investigate mechanisms of action by RT-PCR, ELISA, Western blot, and reporter assays. Topical administration of DHE-Glc attenuated AD-like skin inflammatory symptoms. DHE-Glc decreased infiltration of epidermal eosinophils and mast cells, and reduced levels of IgE, histamine, and mRNA expression and protein levels of CCL17/CCL22 in the plasma of DNCB-treated animals. In addition, DHE-Glc suppressed TNF-α/IFN-γ-induced expression of the Th2 chemokines CCL17 and CCL22 by inhibiting NF-κB and STAT activation in TNF-α/IFN-γ-induced HaCaT cells. DHE-Glc improved AD-like skin inflammatory symptoms on the backs of DNCB-induced mice, partly by suppressing production of Th2 chemokines, CCL17 and CCL22 in inflamed skin. Therefore, DHE-Glc is a potential therapeutic agent for skin inflammatory diseases such as AD.

Jung M ，Lee TH ，Oh HJ ，Kim H ，Son Y ，Lee EH ，Kim J ... -  《-》