Antioxidative and inflammatory responses in spleen and head kidney of yellow catfish (Pelteobagrus fulvidraco) induced by waterborne cadmium exposure

Abstract

Cadmium (Cd) is an environmental contaminant that presents significant threat to aquatic organisms. This study was conducted to examine histological structure as well as antioxidative and inflammatory responses in spleen and head kidney of yellow catfish after 8 weeks of exposure to 50 and 200 μg/L Cd2+ It showed that Cd2+ exposure induced Cd accumulation and impaired histological structure in the spleen and head kidney. For antioxidative response: In the spleen, sod1 expression was significantly up-regulated by 50 and 200 μg/L Cd2+ while cat, gpx1, gstω1 and nrf2 expressions were up-regulated by 50 μg/L Cd2+ but not by 200 μg/L Cd2+ in the head kidney, these genes were down-regulated by Cd2+ exposure. For inflammatory response: In the spleen, the expression of il-8, tnf-α and il-10 were up-regulated by 50 μg/L Cd2+ but not by 200 μg/L Cd2+ while the expression of tor and tgf-β were significantly up-regulated only by 200 μg/L Cd2+ in the head kidney, Cd2+ exposure down-regulated the expression of il-1β, il-8, tor, tnf-α, il-10 and tgf-β. Therefore, this study suggested that Cd2+ exposure could cause Cd accumulation in the spleen and head kidney, and induced histological lesions, antioxidative and inflammatory responses in both tissues.