[Attenuation and mechanism of endoplasmic reticulum stress-mediated hepatocyte apoptosis in rats with alcohol-induced liver injury by qinggan huoxue recipe and its disassembled formulas]

Abstract

Objective: To explore attenuation and mechanism of endoplasmic reticulum stress (ERS)-mediated hepatocyte apoptosis in rats with alcohol-induced liver injury by Qinggan Huoxue Recipe (QGHXR) and its disassembled formulas (Qinggan Recipe and Huoxue Recipe respectively).

Methods: A rat model of chronic alcoholic liver injury was successfully established using a compound reagent of alcohol, corn oil, and pyrazol. The modeled rats were randomly divided into the model group, the QGHXR group, the Qinggan Recipe (QGR) group, and the Huoxue Recipe group (HXR). The CCl4 control group and the normal control group were also set up. There were ten rats in each group. All rats of modeled groups were gastrogavaged with alcohol compound reagent every morning. Rats in the QGHXR group (at the daily dose of 9. 5 g/kg, QGR group (at the daily dose of 3.0 g/kg), and HXR group (at the daily dose of 6.5 g/kg) were administered with corresponding medicines by gastrogavage every afternoon. Equal volume of normal saline was given to rats of the model group by gastrogavage. CCl4 was intraperitoneally injected at the dose of 0.3 mL/kg to rats in the CCl4 control group, once per week. Normal saline was given to rats in the normal control group by gastrogavage. The treatment was lasted for two weeks. Pathological changes of the liver were observed by histopathology. Serum total homocysteine (tHCY) level was detected by ELISA. The hepatocyte apoptosis rate was detected using flow cytometry. The gene and protein expressions of eukaryotic translation initiation factor 2 alpha (elF-2alpha), phosphorylation elF-2alpha (pelF-2alpha), glucose-regulated protein 78 (GRP78), and Caspase-3 in the liver were examined using Real-time PCR and Westen blot respectively.

Results: Compared with the normal control group, typical pathological changes of chronic alcoholic liver injury such as steatosis, inflammation, and even fibrosis occurred in model rats. The hepatocyte apoptosis obviously increased, with the apoptosis rate reaching the five-fold of that in normal rats. Besides, early apoptosis dominated. The serum tHCY level significantly increased. The expressions of p-elF-2alpha, GRP78, and Caspase-3 protein obviously increased (P < 0.01). Expressions of GRP78 and Caspase-3 mRNA significantly increased (P < 0.05, P < 0.01). Compared with the model group, the degrees of the liver injury and the hepatocyte apoptosis in the QGHXR group, the QGR group, and the HXR group were significantly alleviated. The serum tHCY level was significantly lowered. The protein expressions of p-elF-2a, GRP78, and Caspase-3 obviously decreased (P < 0.01). mRNA expressions of GRP78 and Caspase-3 obviously decreased in the QGHXR group (P < 0.05, P < 0.01). Only GRP78 mRNA expression obviously decreased in the QGR group (P < 0.05).

Conclusion: QGHXR and its disassembled formulas could attenuate ERS-mediated hepatocyte apoptosis in alcohol-induced liver injury rats by lowering the serum tHCY level and expressions of ERS apoptosis correlated factors.