A Comparison of Mesenchymal Stem Cell-derived Hepatocyte-like Cells and HepG2 Cells for Use in Drug-Induced Liver Injury Studies

Abstract

Liver cell lines obtained from hepatomas, for example, HepG2 cells, are commonly used in drug toxicity studies. However, functional hepatocyte-like cells derived from mesenchymal stem cells (MSCs) could be a better option for use in the study of drug metabolism and toxicity. Overdose of acetaminophen (APAP) and excess alcohol consumption are common causes of liver damage. The objective of the present study was to investigate the use of MSC-derived hepatocyte-like cells (MSCdH) in the assessment of drug-induced liver injury (by using APAP and ethanol), and to compare the toxic effects observed in the MSCdH with those exhibited by HepG2 cells. MSCs were isolated from umbilical cord and their functionality confirmed by their ability to differentiate into adipocytes, osteocytes and hepatocyte-like cells. It was shown that the MSCs successfully differentiated into hepatocyte-like cells, and these cells were further characterised by using various enzyme assays and by assessing albumin secretion and urea synthesis. Cytotoxicity was evaluated in the HepG2 and MSCdH after exposure to ethanol and APAP, with cell viability being determined by using the MTT assay. After exposure to ethanol and to APAP, cell viability decreased in a concentration-dependent manner for both types of hepatocytes. The respective EC₅₀ values of ethanol-induced toxicity for HepG2 and MSCdH cells were 2.5% and 1.3% v/v (p < 0.001); for APAP-induced toxicity they were 19.1 mM and 12.6 mM (p < 0.001). These findings show that there is a distinct difference between the two types of hepatocytes in terms of APAP-induced and ethanol-induced liver injury.