Objective: To investigate the mechanism of Radix Kansui (RK) stir-fried with vinegar (VRK) decreased hepatotoxicity in mice.
Methods: According to a random number table, 40 mice were randomly divided into negative control group (0.5% carboxymethylcellulose sodium, 20 mL/kg), positive control group (0.1% mixture of carbon tetrachloride in soybean oil, 20 mL/kg), RK group (the ethyl acetate extracts of RK, 250 g crude drug/kg) and VRK group (the ethyl acetate extracts of VRK, 250 g crude drug/kg) with 10 mice per group. All mice were administered orally by gavage daily for 7 continuous days. The morphology of liver tissues was examined to assess the liver injury by a transmission electron microscope. Hepatocyte apoptosis in vivo was determined by terminal deoxynucleotidyltransferase-mediated dUTP-biotin nickend labeling (TUNEL) assay. Immunohistochemical technique was adopted to detect the expression of particular antiapoptotic and proapoptotic proteins in the mitochondrial pathways, including B-cell lymphoma (Bcl-2) and caspase-3, as well as the expression of inflammatory mediators, including nuclear factor kappa B (NF- κ B) and intercellular adhesion molecule-1 (ICAM-1).
Results: Liver injury and hepatocyte apoptosis were observed in RK mice, and the liver injury were significantly reduced in VRK-treated mice. In immunohistochemistry study, compared with the negative control group, RK inhibited dramatically the Bcl-2 protein expression and significantly increased the expression of caspase-3, NF- κ B and ICAM-1 (all P<0.01). Compared with the RK group, VRK group induced significant increase on Bcl-2 protein expression, and decreased the caspase-3, NF- κ B and ICAM-1 protein expression (P<0.05 or P<0.01).
Conclusion: The mechanism of reduced hepatotoxicity of VRK may be associated with the reduced inflammation, regulation of antiapoptotic and proapoptotic mediators in the mitochondrial pathway.
Keywords: Chinese medicine; Radix Kansui; apoptosis; hepatotoxicity; inflammation; mitochondrial pathway.