AhR-mediated lipid peroxidation contributes to TCDD-induced cardiac injury in zebrafish

2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is a persistent environmental contaminant. Previous reports revealed TCDD activating aryl hydrocarbon receptor (AhR) pathway and causing cardiac damage. However, the mechanism of AhR-induced cardiac defect in response to TCDD exposure remains unclear. In this study, we characterized the impacts of TCDD exposure on heart morphology and cardiac function in zebrafish. To investigate the differentially expressed genes under TCDD exposure, we collected the zebrafish larave heart from the control and TCDD treatment groups. We then performed gene expression profiling analysis using data obtained from RNA-seq. Transcriptomic profiling showed that, along with an upregulation of the AhR signaling pathway by TCDD, the expression of pro-ferroptosis genes was upregulated, while genes implicated in glutathione metabolism were downregulated. Consistently, lipid peroxidation, as indicated by malonaldehyde (MDA) production, increased in TCDD-exposed cardiac tissue. Accordingly, inhibiting lipid peroxidation with Liproxstatin-1 reversed the adverse cardiac effects under TCDD treatment. Together, our findings demonstrate that AhR-mediated lipid peroxidation contributes to the cardiac developmental defects of TCDD during zebrafish early development. Comparative gene expression profiling analysis of RNA-seq data for the zebrafish heart of the control and TCDD treatment groups.