Resolvin-D1 inhibits interleukin-8 and hydrogen peroxide production induced by cigarette smoke extract in 16HBE cells via attenuating NF-κB activation

Abstract

Background Cigarette smoke induced airway inflammation plays a role in pathogenesis of airway inflammation. Resolvin-D1 derived from omega-3 polyunsaturated fatty acids is an endogenous anti-inflammatory and proresolving lipid mediator. Resolvin-D1 ameliorated inflammatory responses in lung injury, asthma, peritonitis and atherosclerosis. We investigated whether resolvin-D1 suppressed the productions of chemokines and oxidative stress induced by cigarette smoke extract (CSE) in vitro and its possible mechanism. Methods We examined the proinflammatory chemokine interleukin-8 and hydrogen peroxide (H2O2) productions induced by CSE in 16 human bronchial epithelial (16HBE) cells after resolvin-D1 treatment and their mechanisms. 16HBE cells were treated with resolvin-D1 at up to 10 nmol/L, for 30 minutes before CSE up to 16% (v/v) exposure. Release of interlukin-8 proteins was assessed by enzyme linked immunosort assay (ELISA) and its mRNA level by RT-PCR. We evaluated extracellular H2O2 expression in the supernatant. Phosphorylation of NF-κB/p65 and degradation of I-κB in 16HBE cells were determined by Western blotting analysis and NF-κB DNA binding activity by electrophoretic mobility shift assay (EMSA). Results 16HBE cells treated with 8% CSE showed significantly higher interlukin-8 production. Resolvin-D1 pretreatment inhibited CSE induced interlukin-8 production (mRNA and protein) in a dose and time dependent manner. Extracellular H2O2 level decreased after resolvin-D1 treatment. Resolvin-D1 attenuated CSE triggered I-κB degradation and NF-κB/p65 activation dose dependently and inhibited NF-κB DNA binding activity. Conclusion Resolvin-D1 inhibits CSE induced interlukin-8 and H2O2 production in 16HBE cells by modulating NF-κB activation and has therapeutic potential for pulmonary inflammation.