Integrated cell-mouse metabolomics reveals toxicity mechanisms and biomarkers of prothioconazole exposure

Prothioconazole (PTC) is one of the most widely used triazole fungicides worldwide, while its major metabolite, prothioconazole-desthio (dPTC), exhibits enhanced toxicological potential. However, the metabolic perturbations induced by chronic PTC exposure and sensitive biomarkers for exposure monitoring remain poorly understood. This study aimed to elucidate the metabolic toxicity mechanisms of PTC and identify reliable biomarkers using integrated in vitro and in vivo metabolomics.

Cytotoxicity assays demonstrated significant differences in the toxicity of eight representative pesticides toward L-02 hepatocytes, with half-maximal inhibitory concentration (IC₅₀) values of 102.8 and 167.3 μmol L^-1 for PTC and dPTC, respectively. Untargeted metabolomics revealed that PTC exposure significantly disturbed lipid metabolism, nicotinate metabolism, amino acid metabolism, and mitochondrial energy homeostasis. Corticosterone, equol, and uric acid exhibited excellent discriminatory performance (area under the curve (AUC) > 0.95) and were identified as potential cellular biomarkers of exposure. In C57BL/6J mice, chronic PTC exposure for 28 days induced systemic metabolic disturbances involving the tricarboxylic acid cycle, lysine degradation, and host-microbiota co-metabolism. Targeted metabolomics further validated significant increases in succinic acid, heptanedioic acid, and 2-oxohexanedioic acid, together with a marked decrease in indole-3-propionic acid, consistent with the untargeted metabolomics results. These metabolites demonstrated high sensitivity and specificity for discriminating PTC exposure.

This study demonstrates that chronic PTC exposure disrupts mitochondrial energy metabolism and multiple metabolic pathways, leading to systemic metabolic dysfunction. The identified metabolic biomarkers provide promising tools for pesticide biomonitoring and mechanistic toxicity assessment, improving exposure surveillance and health risk evaluation of triazole fungicides. © 2026 Society of Chemical Industry.