High-content analysis of in vitro hepatocyte injury induced by various hepatotoxicants.

In vitro prediction of hepatotoxicity can enhance the performance of non-clinical animal testing for identifying the hazards of chemicals. Here, we assessed high-content analysis (HCA) using multi-parameter cell-based assays as an in vitro hepatotoxicity testing model using various hepatotoxicants and human hepatocytes such as HepG2 cells and human primary hepatocytes (hPHs). Both types of hepatocyte were exposed to multiple doses of ten hepatotoxicants associated with liver injury whose mechanisms of action are known. HCA data were obtained using fluorescence probes for nuclear size (Hoechst), mitochondrial membrane potential (TMRM), cytosolic free calcium (Fluo-4AM), and lipid peroxidation (BODIPY). Cellular alterations were observed in response to all hepatotoxicants tested. The most sensitive parameter is alteration of TMRM, with high sensitivity at low dose, then BODIPY, followed by Fluo-4AM. HCA data from HepG2 cells and hPHs were generally concordant, although some inconsistencies were noted. Both types of hepatocyte showed mild or severe mitochondrial impairment and lipid peroxidation in response to several hepatotoxicants. These findings demonstrate that the application of HCA to in vitro hepatotoxicity testing enables more efficient hazard identification, and further suggests that certain parameters could serve as sensitive endpoints for predicting the hepatotoxic potential of chemical compounds.