Jun Chul Parka, 1, Jeonghoon Hana, 1, Min-Chul Leea, Hye-Min Kanga, Chang-Bum Jeonga, Dae-Sik Hwanga, Minghua Wangb, Jae-Seong Leea,*
a Department of Biological Science, College of Science, Sungkyunkwan University, Suwon 16419, South Korea
b Center for Marine Environmental Chemistry and Toxicology, College of the Environment & Ecology, Xiamen University, Xiamen 361102, China
1These authors contributed equally to this work.
2,2’,4,4’-tetrabromodiphenyl ether (BDE-47) is widely dispersed endocrine disrupting chemicals (EDCs) in the aquatic ecosystem. Due to its devastating effect on marine organisms and insufficient database on toxicology, we investigated the adverse effects of BDE-47 on life parameters and antioxidant defense system following the reactive oxygen species (ROS) production in the monogonont rotifer Brachionus koreanus. In B. koreanus, the reduction in life cycle, fecundity, and population growth were observed in response to BDE-47. 50 μg/L BDE-47 significantly reduced (P<0.05) life expectancy and net reproductive rate. In response to 10 to 50 μg/L BDE-47 exposure, the oxidative stress was elicited via the generation of ROS, while the antioxidant related enzymes (e.g. glutathione S-transferase [GST] and glutathione reductase [GR]) have demonstrated significant activity levels (P < 0.05) to further alleviate the oxidative stress in a concentration dependent manner. Furthermore, transcript profiles of antioxidant function (GST-A, -O, and -S1-S8)-related genes have shown the significant increase over 24 h in response to BDE-47 (0, 10, 25, and 50 μg/L). As for MAPK signaling pathway analysis, up-regulation of their activities was observed at 25 μg/L BDE-47 but their activities have reduced at adult NOEC concentration of 50 μg/L. This study provides a better understanding of the effects of BDE-47 on life parameters, molecular defense system, and activation of MAPK signaling pathway against generated oxidants in the rotifer.
Keywords : Rotifer; Brachionus koreanus; BDE-47; Antioxidant system; Life parameters; MAPK signaling pathway