Low concentrations of dibromoacetic acid and N-nitrosodimethylamine induce several stimulatory effects in the invertebrate model Caenorhabditis elegans

• Published in: Chemosphere (Oxford) 2015-04, Vol.124, p.122-128
• Main Authors: Baberschke, Nora, Steinberg, Christian E.W., Saul, Nadine
• Format: Article
• Language: English
• Subjects: Acetates - toxicity; Animals; Body Size - drug effects; Caenorhabditis elegans - drug effects; Caenorhabditis elegans - physiology; Dibromoacetic acid; Dimethylnitrosamine - toxicity; Dose-Response Relationship, Drug; Down-regulation; Energy conservation; Energy Metabolism - drug effects; Environmental Pollutants - toxicity; Gene transcription; Genes; Invertebrates; Life history traits; Life span; Longevity - drug effects; Low concentrations; N-nitrosodimethylamine; Stimulatory effects; Stress concentration; Stresses; Toxic; Toxicology
• ISSN: 0045-6535; 1879-1298
• DOI: 10.1016/j.chemosphere.2014.12.002

•Dibromoacetic acid and N-nitrosodimethylamine are ubiquitously distributed.•Both are considered toxic and carcinogenic at high concentrations.•Stimulatory effects on C. elegans were detected at relatively low concentrations.•DBAA and NDMA have life-extending effects and increase body length.•The down-regulation of most stress-related genes may indicate an energy saving mode. Dibromoacetic acid (DBAA) and N-nitrosodimethylamine (NDMA) have natural and anthropogenic sources and are ubiquitously distributed in the environment. They are classified as toxic and carcinogenetic and various studies have addressed their effects on vertebrates. Furthermore, there is no information about the whole-organism effects at low concentrations or about their impact on invertebrates. Therefore, these compounds were studied with the model invertebrate Caenorhabditis elegans (C. elegans) at relatively low concentrations. Biological tests (life span, reproduction, body size, thermal stress resistance) as well as biochemical (pro- and antioxidative capacity and lipid peroxidation) and biomolecular assays (transcription of stress genes) were performed. None of the applied concentrations showed a toxic potential. Instead, they extended life span and increased the body length. Both xenobiotics did not cause oxidative stress or DNA damages, or acted as endocrine disruptors. The stimulatory effects on C. elegans were most likely not a result of an induced protective stress response. Instead, an ‘energy saving mode’, indicated by the reduced transcription of many stress response genes, could have provided additional resources for longevity and growth. Although both substances are potentially toxic at higher doses, the present study underlines the importance of testing lower concentrations and their impact on invertebrates.