D-Saccharic acid 1,4-lactone (DSL) is a derivative of D-glucaric acid. It is a beta-glucuronidase inhibitor and possesses anticarcinogenic, detoxifying, and antioxidant properties. In the present study, the protective effects of DSL were investigated against tertiary butyl hydroperoxide (TBHP) induced cytotoxicity and cell death in vitro using murine hepatocytes. Exposure of TBHP caused a reduction in cell viability, enhanced the membrane leakage, and disturbed the intracellular antioxidant machineries in murine hepatocytes. Investigating the signaling mechanism of TBHP-induced cellular pathophysiology and protective action of DSL, we found that TBHP exposure disrupted mitochondrial membrane potential, facilitated cytochrome c release in the cytosol, and led to apoptotic cell death via mitochondria-dependent pathways. DSL counteracted these changes and maintained normalcy in hepatocytes. Combining, results suggest that DSL possesses the ability to ameliorate TBHP-induced oxidative insult, cytotoxicity, and apoptotic cell death probably due to its antioxidant activity and functioning via mitochondria-dependent pathways. (c) 2011 Wiley Periodicals, Inc. J Biochem Mol Toxicol 25:341354 2011; View this article online at . DOI 10.1002/jbt.20393