Effects of triclosan on the RedoximiRs/Sirtuin/Nrf2/ARE signaling pathway in mosquitofish (Gambusia affinis)

• Published in: Aquatic toxicology Vol. 230; p. 105679
• Main Authors: Bao, Shuang, He, Cuiping, Ku, Peijia, Xie, Meinan, Lin, Jiawei, Lu, Songhui, Nie, Xiangping
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.01.2021
• Subjects: Animals; Antioxidants - metabolism; Cyprinodontiformes - genetics; Cyprinodontiformes - metabolism; Gene Expression Regulation; MicroRNAs - genetics; MicroRNAs - metabolism; Mosquitofish; NF-E2-Related Factor 2 - genetics; NF-E2-Related Factor 2 - metabolism; Nrf2; Oxidation-Reduction; Oxidative Stress - drug effects; Oxidative Stress - genetics; RedoximiRs; Signal Transduction; Sirtuin; Sirtuins - genetics; Sirtuins - metabolism; Triclosan; Triclosan - toxicity; Water Pollutants, Chemical - toxicity; RedoximiRs; Triclosan; Nrf2; Sirtuin; Mosquitofish
• ISSN: 0166-445X; 1879-1514
• DOI: 10.1016/j.aquatox.2020.105679

•Environmentally relevant concentrations of triclosan caused oxidative stress in mosquitofish and induced the Nrf2/ARE signaling pathway.•The up-regulations Sirt1 and Sirt2 in Sirtuin family could activate the Nrf2/ARE signaling pathway in mosquitofish exposed to triclosan.•The down-regulations of miR-34b and the up-regulations of miR-34a, miR-144 and miR153a-5p modulated the Nrf2/ARE signaling pathway in mosquitofish exposed to triclosan. Triclosan (TCS) has been widely used in daily life for its broad-spectrum antibacterial property and subsequently detected frequently in aquatic waterborne. Environmental relevant concentrations of TCS in water (ng-μg/L) may pose potential unexpected impact on non-target aquatic organisms. In the present work, we investigated the transcriptional responses of Nrf2 as well as its downstream genes, sirtuins and redox-sensitive microRNAs (RedoximiRs) in livers of the small freshwater fish mosquitofish (Gambusia affinis) which were exposed to environmental relevant concentrations of TCS (0.05 μg/L, 0.5 μg/L and 5 μg/L for 24 h and 168 h). Results showed there were similar up-regulations in Nrf2 and its target genes (e. g. NQO1, CAT and SOD) at transcriptional, enzymatic and protein levels, reflecting oxidative stress of TCS to mosquitofish. Meanwhile, up-regulations of Sirt1, Sirt2 and down-regulations of miR-34b, miR-200b-5p and miR-21 could modulate antioxidant system via the Nrf2/ARE signaling pathway by the post-transcriptional regulations. Some oxidative stress-related biomarkers displayed in concentration-dependent manners (e. g. NQO1 mRNA, CAT mRNA) and/or time-dependent manners (e. g. GSH contents). This study indicated that the RedoximiRs/Sirtuin/Nrf2/ARE signaling pathway played a crucial role in mosquitofish exposed to TCS, and there might be potentially profound effects for TCS on the aquatic ecological safety.