Toxicological Assessment of Microcystin-LR to Zebrafish (Danio rerio) Using Metabolomics

Microcystins are one of the most frequently found hepatotoxic cyclic peptides in fresh- and brackish-water. Zebrafish (Danio rerio) were exposed to 20 ppb of microcystin-LR (MCLR) for 72 h in order to investigate the metabolic responses. Proton nuclear magnetic resonance (H-1-NMR) spectroscopy was used to analyze the metabolic profiles. As a result, male and female zebrafish showed different patterns of metabolic perturbation in relation to their detoxification profiles. Glutathione was reduced for the MCLR excretion, and fumarate and creatine were increased for the energy demands required for detoxification in the male zebrafish. The correlation of metabolites in the metabolic pathway network was changed due to MCLR exposure. The correlations connected with myo-inositol, betaine, and NADPH considerably altered in the MCLR-exposed group.