The DPA-derivative 11S, 17S-dihydroxy 7,9,13,15,19 (Z,E,Z,E,Z)-docosapentaenoic acid inhibits IL-6 production by inhibiting ROS production and ERK/NF-κB pathway in keratinocytes HaCaT stimulated with a fine dust PM.

11 S, 17S-dihydroxy 7,9,13,15,19 (Z,E,Z,E,Z)-docosapentaenoic acid (DoPE) is a derivative of docosapentaenoic acid, a specialized pro-resolving mediator of inflammation such as lipoxins, resolvins, maresins, and protectins. PM is a fine dust particle that induces oxidative stress, DNA damage, inflammation, aging, and cancer. The anti-inflammatory mechanism of DoPE, however, has not yet been elucidated. In these studies, we investigated whether DoPE has anti-inflammatory effects in human keratinocyte HaCaT cells. We demonstrated that DoPE suppressed PM-induced expressions of IL-6 mRNA and protein in human HaCaT keratinocytes. We also investigated the modulating effects of DoPE on reactive oxygen species (ROS) and mitogen-activated protein kinase (MAPK). ROS production, extracellular signal regulated kinase (ERK) phosphorylation, and translocation of nuclear factor-kappa B (NF-kB) p65 and NF-kB activity were suppressed by DoPE in PM-stimulated HaCaT cells. Collectively, our results demonstrated that DoPE inhibited IL-6 expression by reducing ROS generation, suppressing ERK phosphorylation, and inhibiting translocation of NF-kB p65 and NF-kB activity in PM-stimulated HaCaT cells, suggesting that DoPE can be useful for the resolution of the inflammation caused by IL-6.