Cantharidin (CTD) is an effective antitumor agent. However, it exhibits significant hepatotoxicity, the mechanism of which remains unclear. In this study, biochemical and histopathological analyses complemented with ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS)-based targeted metabolomic analysis of bile acids (BAs) were employed to investigate CTD-induced hepatotoxicity in rats. Sixteen male and female Sprague-Dawley rats were randomly divided into two groups: control and CTD (1.0 mg/kg) groups. Serum and liver samples were collected after 28 days of intervention. Biochemical, histopathological, and BA metabolomic analyses were performed for all samples. Further, the key biomarkers of CTD-induced hepatotoxicity were identified via multivariate and metabolic pathway analyses. In addition, metabolite-gene-enzyme network and Kyoto Encyclopedia of Genes and Genomes pathway analyses were used to identify the signaling pathways related to CTD-induced hepatotoxicity. The results revealed significantly increased levels of biochemical indices (alanine aminotransferase, aspartate aminotransferase, and total bile acid). Histopathological analysis revealed that the hepatocytes were damaged. Further, 20 endogenous BAs were quantitated via UHPLC-MS/MS, and multivariate and metabolic pathway analyses of BAs revealed that hyocholic acid, cholic acid, and chenodeoxycholic acid were the key biomarkers of CTD-induced hepatotoxicity. Meanwhile, primary and secondary BA biosynthesis and taurine and hypotaurine metabolism were found to be associated with the mechanism by which CTD induced hepatotoxicity in rats. This study provides useful insights for research on the mechanism of CTD-induced hepatotoxicity.

With La, Ce, and Zr as doping additives, Ni-based catalysts were prepared using a plasma-induced micro-combustion method. X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, H 2 temperature-programmed reduction, H 2 temperature-programmed desorption, CO 2 temperature-programmed desorption, and diffuse reflectance infrared Fourier transform spectroscopy (DRIFTs) were used to characterize the as-synthesized catalysts. The results illustrated that the catalysts after doping exhibited higher reducibility and a stronger interaction between the metal and support compared with SiO 2 -supported Ni catalyst without additives. The additives increased the electron density around metal Ni and oxygen vacancies of the support, which promoted the CO 2 and hydrogen adsorption. The catalysts were used in CO 2 methanation, and the 10Ni-3La/SiO 2 catalyst exhibited the highest turnover frequency of 0.517 s −1 and especially the highest CH 4 selectivity of 85% at 280 °C under a high space velocity of 120 000 mL/(gcat•h). DRIFTs analysis confirmed adding additives, especially La and Ce, could accelerate the integration of CO 2 species with dissociated H to generate formate intermediate, which facilitated methane formation.

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