Protective Effects of NRF2 Activator Sulforaphane in Polyinosinic:Polycytidylic Acid-Induced In Vitro and In Vivo Model

NRF2 is a nuclear transcription factor involved in the cellular protection against oxidative stress and inflammatory signaling. Sulforaphane is a known NRF2 activator used for its strong antioxidant and anti-inflammatory activity through regulation of Keap-1-HO-1 pathway. However, there is a limited exploration about the role of NRF2 activator, sulforaphane in regulation of poly(I:C)-induced oxidative stress, inflammation and injury in lung. Therefore, we aimed to evaluate the therapeutic effect of sulforaphane in poly(I:C)-induced responses using in vitro as well as in vivo model. We evaluated oxidative stress and inflammatory cytokines in poly(I:C)-induced RAW264.7 cells. We also employed in vivo animal study to evaluate tissue oxidative-antioxidative balance along with expression of NRF2, Keap-1, histopathological assessment by hematoxylin-eosin staining and picrosirius red staining to explore the protective mechanisms of sulforaphane in poly(I:C)-induced mouse model. Our results indicated that sulforaphane increased the expression of NRF2 and its downstream proteins. In addition, sulforaphane alleviated poly(I:C)-induced activation of the oxidative and pro-inflammatory pathways, histopathological changes, depleted expression of GSH and superoxide dismutase in lung tissue. This study suggested that sulforaphane may be one of the useful therapeutic alternatives for poly(I:C) induced lung injury and inflammation.