Reactive oxygen species are involved in the IFN‐γ‐stimulated production of Th2 chemokines in HaCaT keratinocytes

Abstract

The increased generation of reactive oxygen species (ROS) induces inflammation in different cell types. However, it is unclear whether ROS play an essential role in the production of thymus and activation-regulated chemokine (TARC/CCL17) and macrophage-derived chemokine (MDC/CCL22) in keratinocytes. Here, we investigated the function of ROS in the production of these two Th2 chemokines in interferon-gamma (IFN-γ)-treated HaCaT keratinocytes. We found that IFN-γ-induced production of both chemokines in parallel with the increased generation of intracellular ROS. A ROS scavenger, N-acetyl cysteine (NAC), significantly inhibited the IFN-γ-induced production of chemokines as well as the activation of I kappa-B (IκB)-nuclear factor-kappa B (NF-κB). Inhibitors of Janus family kinases (JAKs), p38 mitogen-activated kinase (MAPK), and NF-κB suppressed IFN-γ-induced production of TARC and MDC. NF-κB activation was inhibited by both inhibitors of JAKs and p38 MAPK. Importantly, IFN-γ-stimulated phosphorylation of p38 MAPK was significantly suppressed by JAKs inhibitors, but not significantly affected by NAC or L-buthionine sulfoximine (L-BSO). However, IFN-γ-stimulated activation of IκB and NF-κB was suppressed by NAC but enhanced by BSO. Furthermore, inhibition of p38 MAPK and JAKs did not affect ROS generation in IFN-γ-stimulated HaCaT cells. These results indicate that intracellular ROS and JAKs/p38 MAPK both contribute independently to IFN-γ-stimulated production of TARC and MDC in HaCaT keratinocytes, by increasing NF-κB activation.

Metabolic Alterations Contribute to Enhanced Inflammatory Cytokine Production in Irgm1-deficient Macrophages

“…Our results are consistent with a previously published study showing that the effect of LC-AC in increasing inflammatory cytokine production is dependent on the ROS tone of the cells (79). They are also consistent with many studies showing that ROS drive chemokine expression, including that in IFN-␥-stimulated cells (80). However, interpretation of our results is tempered by the fact that we did not find an elevation of ROS levels in IFN-␥-primed Irgm1-deficient BMM compared with primed WT BMM.…”

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

“…Our results showed that DHE-Glc inhibited TNF-a/IFNg-induced phosphorylation of JAK2 and p38 MAP kinases and did not inhibit activation of ERK and JNK. Previous studies [24,39,40] and our results showed that p38 MAP kinase and JAK2, but not ERK and JNK kinases, are involved in TNF-a/IFN-g-induced expression of CCL17 and CCL22 in HaCaT cells. These results indicated that DHE-Glc suppressed production of CCL17 in TNF-a/IFN-g-stimulated cells by inhibition of p38 MAPK and JAK2 pathways activated by TNF-a and IFN-g. IFN-g induces expression of responsive genes by activating JAK and STAT1 transcription factor [32].…”

Xanthii fructus extract inhibits TNF-α/IFN-γ-induced Th2-chemokines production via blockade of NF-κB, STAT1 and p38-MAPK activation in human epidermal keratinocytes

“…NF-κB and JAK/STAT signaling pathways contribute to the production of TARC/CCL17 and MDC/CCL22 in TNF-α/IFN-γ-stimulated HaCaT cells (Qi et al, 2011). Therefore, we examined whether adding EXF to TNF-α/IFN-γ-stimulated HaCaT cells has an effect on the activation of the NF-κB and JAK/STAT signaling pathway.…”