Decabromodiphenyl ethane (DBDPE) has increasingly been used as an alternative to decabrominated diphenyl ether (BDE209) in consumer products such as plastics, textiles, furniture, and electric/electronic devices. The potential target tissues and toxic effects of DBDPE in aquatic organisms remain largely unknown at present, despite its widespread detection in various environments and biotic mediums.
A research group led by Prof. ZHOU Bingsheng from the Institute of Hydrobiology (IHB) of the Chinese Academy of Sciences has found that DBDPE accumulated mostly in the brain and primarily affected the biological processes associated with muscle contraction and estrogenic response in female zebrafish. Relevant results were published on Environmental Science & Technology.
In this study, the researchers first conducted chemical analyses on female zebrafish to determine where DBDPE accumulates in different tissues including brain, liver, and gonad. They found that DBDPE tended to accumulate in the brain other than the liver and gonad.
They then applied tandem mass tag (TMT)-based quantitative proteomics coupled with parallel reaction monitoring to screen the primary toxic effects of DBDPE in brain tissue. Bioinformatics analysis showed that DBDPE mainly affected the biological process related to muscle contraction and estrogenic response.
They further analyzed intracellular Ca2+ contents and locomotor behavior to confirm muscle contraction disruption. Results indicated that DBDPE exposure can affect the muscle contraction via muscular related proteins and intracellular Ca2+ homeostasis, and ultimately affect the locomotor activity in female zebrafish.
By measuring the transcription of the hypothalamic-pituitary-gonad-liver axis genes, sex hormone levels, and gonadal histopathology, the researchers confirmed that exposure to DBDPE can affect the reproductive endocrine system of female zebrafish.
In summary, using female adult zebrafish, the study characterized the brain for the first time as the primary target organ of DBDPE. It can provide important clues for further mechanism studies and risk assessment of DBDPE.
