ABSTRACT
ObjectiveTo investigate the principle and scientific connotation of Euodiae Fructus（EF） processed with Glycyrrhizae Radix et Rhizoma（Gly） by comparing the effects of unprocessed products of EF（UEF） and processed products of EF with the different proportions of Gly（GEFs） at toxic doses on oxidative stress and autophagy in the liver of mice. MethodSeventy mice were randomly divided into 7 groups， namely the control group， the UEF group， the group of the processed products of EF without Gly（PEF） and 4 groups of GEFs（the mass ratios of EF to Gly were 100∶3， 100∶6， 100∶12 and 100∶24， respectively， hereinafter referred to as the processed products of EF with the mass ratios of 100∶3， 100∶6， 100∶12 and 100∶24 of Gly）. The mice were given purified water， the decoction of UEF， PEF and GEFs by gavage at a dose of 30 g·kg-1. PEF and GEFs were prepared according to the method under EF in the 2020 edition of Chinese Pharmacopoeia. Levels of alanine aminotransferase（ALT） and aspartate aminotransferase（AST） were determined by ultraviolet-visible spectrophotometry， hematoxylin-eosin（HE） staining was used to evaluate the pathological changes of liver tissue， the level of reactive oxygen species（ROS） was detected by fluorescence method， the mRNA expression of heme oxygenase-1（HO-1）， quinone oxidoreductase-1（NQO1）， glutathione-S-transferase 1（GSTA1）， Kelch-like epichlorohydrin-associated protein 1（Keap1） and p62 were measured by Real-time fluorescence quantitative polymerase chain reaction（Real-time PCR）， western blot was used to detect the protein expression of phosphorylated mammal target of rapamycin（p-mTOR）， phosphorylated ribosomal p70 S6 protein kinase（p-p70S6K）， p62， microtubule-associated protein 1 light chain 3Ⅰ（LC3Ⅰ） and LC3Ⅱ. ResultCompared with the control group， after 7 d of administration， the increase in body mass of mice in the UEF group began to slow down and the difference gradually increased， and the liver body index significantly increased（P<0.01）， pathomorphological observation showed that the structure of hepatic lobules was disordered， and local hepatic sinuses were narrowed or disappeared， and there were inflammatory infiltration and local bleeding， the levels of ALT and AST in serum and ROS in liver tissue were significantly increased（P<0.01）， and the expressions of Keap1， HO-1， NQO1， GSTA1， p62 mRNA and p-mTOR， p-p70S6K， p62 protein in liver tissue were significantly decreased（P<0.01）， and LC3Ⅱ/LC3Ⅰ was significantly increased（P<0.01）. Compared with the UEF group， the body mass of mice increased， and the liver body index， the levels of ALT and AST in serum， and the level of ROS in liver tissue all decreased in the groups of PEF and GEFs. Among these groups， only the liver lobules in GEF（100∶6） group were intact， and the size of liver sinuses was close to that in the control group. The mRNA expressions of Keap1， HO-1， NQO1， GSTA1 and p62 in liver tissue showed an overall upward trend in the groups of PEF and GEFs. Among these groups， only the ones of the above mRNA in the GEF（100∶6） group had a significant increase（P<0.05， P<0.01）. The protein expressions of p-mTOR， p-p70S6K， p62 and LC3Ⅱ/LC3Ⅰ had a callback in the groups of PEF and GEFs， of which the protein expressions of p-mTOR， p-p70S6K and LC3Ⅱ/LC3Ⅰ in the GEF（100∶6） group and the expression of p62 protein in the GEF（100∶24） group had the largest callback. Except for p-mTOR protein， other protein expressions were statistically significant（P<0.05， P<0.01）. ConclusionThe hepatotoxicity of EF is closely related to its ability to induce oxidative stress， which leads to pathological autophagy and hepatocyte damage. This ability can be reduced by the processing with different proportions of Gly， especially the ratio of 100∶6.