Elucidating the mechanism of hepatotoxicity in Euodia rutaecarpa: insights from QSAR toxicity prediction and metabolomics

Objective: Euodia rutaecarpa, (Wu Zhu Yu) a Chinese medicine clinically used to treat gastrointestinal disorders, has been widely employed. However, Euodia rutaecarpa is regarded as a small toxic traditional Chinese medicine in the Chinese Pharmacopoeia and other herbal works. Using toxicity predictions combined with in vitro and in vivo studies, this study aimed to identify the toxic components and toxic target organs of Euodia rutaecarpa, and explore its toxic mechanism from a metabolic perspective. Methods: The toxic target organs of Euodia rutaecarpa were identified through in vitro and in vivo studies. In vitro toxicity screening was performed by alkaloid enrichment and isolation. The potential toxicity of compounds was predicted by Absorption, Distribution, Metabolism, Excretion, and Toxicity Predictor (ADMET Predictor) based on Quantitative Structure–Activity Relationship (QSAR) construction. In addition, the study integrated the serum metabolomic analysis after the administration of potentially toxic components to clarify the effect of potentially toxic substances on metabolism in mice. Results: Comparing the acute toxicity in mice of different extraction methods and before and after processing, it was evident that Euodia rutaecarpa alcoholic extract had the highest toxicity, and the target organ of Euodia rutaecarpa toxicity was the liver. The alkaloid fraction of alcoholic extract of Euodia showed strong cytotoxicity. The potential toxicity of Euodia rutaecarpa was calculated and predicted by ADMET Predictor, and alkaloids are suspected to be responsible for the toxicity of Euodia rutaecarpa. Evodiamine significantly reduced the number of cells and increased the mitochondrial membrane potential in vitro . Different metabolites were significantly identified by serum metabolomics, of which bile acid metabolism and steroid hormone biosynthesis are the key pathways of hepatotoxicity. Conclusions: Clarify the scientific significance of clinical use of processed products by comparing the acute toxicity of different extraction methods before and after processing. Combining the toxicity prediction based on QSAR with the toxicity screening in vitro and in vivo , the potential toxic target organs and toxic components of Euodia rutaecarpa can be identified. Through metabolomics, we preliminarily revealed that the hepatotoxicity of Euodia rutaecarpa may be related to bile acid metabolism and steroid hormone biosynthesis. This study lays the foundation for elucidating the mechanism of Euodia rutaecarpa and evaluating its safety and quality.