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Protective effects of baicalein on tert-butyl hydroperoxide-induced hepatic toxicity in rat hepatocytes

Institute of Medicine, Medical College, Chung Shan Medical University, Taichung, 402, Taiwan.
Journal of Biomedical Science (Impact Factor: 2.74). 02/2005; 12(2):389-97. DOI: 10.1007/s11373-005-1572-8
Source: PubMed

ABSTRACT Baicalein (BAL), a main flavonoid constituent of Scutellaria radix, was studied for its inhibitory effects on tert-butyl hydroperoxide (t-BHP)-induced hepatotoxicity and oxidative damage in primary cultures of rat hepatocytes. In a preliminary study, baicalein revealed effective antioxidant properties in a test of its capacity to quench the 1,1-diphenyl-2-picrylhydrazyl radical (DPPH). Further investigations showed that baicalein, at the concentrations of 1, 5, and 10 microM, decreased the leakage of lactate dehydrogenase (LDH) and alanine aminotransferase (ALT) and the formation of malondialdehyde (MDA) induced by 30 min of pretreatment with t-BHP (1.5 mM) in primary cultures of rat hepatocytes. Baicalein also attenuated t-BHP-induced mitochondrial depolarization as determined by a retention test of rhodamine 123 and DNA repair synthesis as evidenced by unscheduled DNA synthesis (UDS). In addition, baicalein decreased the 8-hydroxy-2'-deoxyguanosine (8-OH-dG) content which acts as a DNA damage marker. The sum of the results suggests that the protective effect of baicalein against the cytotoxicity and genotoxicity of hepatocytes induced by t-BHP is due to its ability to quench free radicals.

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    • "Recent studies have shown that baicalein has beneficial effects in the liver. Baicalein attenuates tert-butyl hydroperoxide-induced hepatic toxicity in rat hepatocytes (Hwang et al., 2005). Baicalein inhibits hepatocellular carcinoma cells invasion and metastasis by reducing cell motility and migration (Chen et al., 2013). "
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    • "The hepatocellular carcinoma cell lines HepG2 and SK-Hep1 were obtained from the American Tissue Culture Collection (ATCC, USA) and grown to confluence in Dulbecco's minimum essential medium (Gibco, USA) supplemented with 10% fetal bovine serum (Gibco, USA), 2 mM Glutamine, 1% non essential amino acids (NEAA) and a 1% antibiotic mixture (50 mg/mL of penicillin, 50 mg/ mL of streptomycin, and 10 mg/mL of neomycin/mL) at 37 C in a humidified atmosphere of 5% CO 2 . The primary rat hepatocytes were isolated from Wistar rats as previously described [14]. The isolated hepatocytes (viability > 90%) were prepared by liver perfusion with collagenase IV (Sigma) and separated by density centrifugation in Percoll solution (GE Healthcare Bio-Sciences AB). "
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