Corticotropin-Releasing Hormone Inhibits Nuclear Factor-κB Pathway in Human HaCaT Keratinocytes

Abstract

Treatment of human HaCaT keratinocytes with corticotropin-releasing hormone modulates cell proliferation and expression of inflammation markers. In this study we report that corticotropin-releasing hormone also inhibits nuclear factor-κB binding and transcriptional activity. Incubating cells in the absence of growth factors increased nuclear factor-κB activity; this effect was significantly attenuated by corticotropin-releasing hormone. Specifically, corticotropin-releasing hormone downregulated p50/p50 and p50/p65 dimers of nuclear factor-κB, diminished κB-driven CAT reporter gene activity and inhibited IκB-β degradation. Moreover, corticotropin-releasing hormone inhibited the transcription of the nuclear factor-κB responsive genes, interleukin-2 and heat shock protein 90.