ObjectiveTo investigate the mechanism of liver injury induced by tripterygium glycosides tablets （TG） and the molecular mechanism of compound glycyrrhizin tablets （CG） in alleviating the abnormalities of cholesterol metabolism caused by TG via cholesterol metabolism. MethodsAccording to the body weights， male Sprague-Dawley （SD） rats were randomly grouped as follows： control （pure water）， low-dose TG （TG-L， 189.0 mg·kg^-1·d^-1）， high-dose TG （TG-H， 472.5 mg·kg^-1·d^-1）， TG-L+CG （189.0 mg·kg^-1·d^-1 TG + 20.25 mg·kg^-1·d^-1 CG）， and TG-H+CG （472.5 mg·kg^-1·d^-1 TG + 20.25 mg·kg^-1·d^-1 CG）， with 6 rats in each group. Rats were administrated with corresponding drugs once daily for 3 weeks. At the end of the last administration， the mRNA and protein levels of liver X receptor-alpha （LXR-α）， low-density lipoprotein receptor （LDLR）， adenosine triphosphate-binding cassette transporter A1 （ABCA1）， adenosine triphosphate-binding cassette transporter G1 （ABCG1）， 3-hydroxy-3-methylglutaryl coenzyme A reductase （HMGCR）， cholesterol 7α-hydroxylase （CYP7A1）， cholesterol 12α-hydroxylase （CYP8B1）， and sterol 27-hydroxylase （CYP27A1） in the liver tissue were determined by Real-time PCR and Western blotting， respectively. The level of 3-hydroxy-3-methylglutaryl coenzyme A reductase （HMG-CoAR）， a regulatory enzyme of cholesterol synthesis， was measured by enzyme-linked immunosorbent assay （ELISA）. HepG2 cells were used to observe the effect of TG on the cell proliferation in vitro. Specifically， HepG2 cells were grouped as follows： Low-dose TG （TG-l， 15 mg·L^-1）， medium-dose TG （TG-m， 45 mg·L^-1）， high-dose TG （TG-h， 135 mg·L^-1）， fenofibrate （FB， 10 μmol·L^-1）， CG extract， TG-h+FB （135 mg·L^-1 TG + 10 μmol·L^-1 FB）， TG-m+FB （45 mg·L^-1 TG + 10 μmol·L^-1 FB）， TG-l+FB （15 mg·L^-1 TG + 10 μmol·L^-1 FB）， TG-h+CG （135 mg·L^-1 TG + 60 μmol·L^-1 CG）， TG-m+CG （45 mg·L^-1 TG + 60 μmol·L^-1 CG）， and TG-l+CG （15 mg·L^-1 TG + 60 μmol·L^-1 CG）. The mRNA and protein levels of LXR-α， ABCG1， LDLR， CYP7A1， CYP8B1， and CYP27A1 in HepG2 cells were determined by Real-time PCR and Western blotting， respectively. ResultsThe rat experiment showed that compared with the control group， the TG-H group showed down-regulated mRNA levels of CYP7A1， CYP8B1， and CYP27A1 in the liver tissue （P<0.05， P<0.01）， which were up-regulated by the application of CG （P<0.05， P<0.01）， and the TG-H+CG group showed up-regulated mRNA level of LDLR （P<0.01）. Compared with the control group， the TG-L and TG-H groups showed down-regulated protein levels of LDLR， CYP7A1， and CYP8B1 in the liver tissue （P<0.05， P<0.01）. In addition， the protein levels of ABCG1 and LXR-α were down-regulated in the TG-H and TG-L groups， respectively （P<0.05）. Compared with TG alone， TG+CG up-regulated the protein levels of ABCG1 and LDLR （P<0.05， P<0.01）， and the protein levels of CYP7A1 and CYP8B1 in the TG-H+CG group were up-regulated （P<0.05， P<0.01）. The cell experiment showed that compared with the control group， the TG-h group presented up-regulated mRNA level of LXR-α （P<0.01）， and the TG-m and TG-h groups showcased down-regulated mRNA levels of LDLR and CYP7A1 （P<0.01） and up-regulated mRNA level of CYP27A1 （P<0.01） in HepG2 cells. The combination of CG with TG restored the above changes （P<0.01）. Western blotting results showed that compared with the control group， the TG-m and TG-h groups showed down-regulated protein levels of LXR-α， ABCG1， LDLR， CYP7A1， CYP8B1， and CYP27A1 in HepG2 cells （P<0.01）. Compared with the TG-h group， the TG-h+CG group showed up-regulated protein level of LDLR （P<0.05）. Compared with the TG-m group， the TG-m+CG group showcased up-regulated protein levels of LDLR， ABCG1， CYP7A1， and CYP27A1 （P<0.05， P<0.01）. ConclusionThe administration of TG at 189.0， 472.5 mg·kg^-1 for 3 weeks could modulate the signaling pathways associated with cholesterol efflux， endocytosis， and cholesterol biotransformation in hepatocytes， leading to the accumulation of cholesterol and subsequent liver injury in rats. CG could ameliorate the liver injury induced by lipid metabolism disorders caused by TG by up-regulating the expression of LXR-α， LDLR， ABCG1， CYP7A1， CYP8B1， and CYP27A1 to promote cholesterol biotransformation.

Objective:To establish a quality standard system for Descurainiae Semen under the requirements of German Pharmaceutical Codex (DPC); To compare the similarities and differences between DPC and the Pharmacopoeia of the People's Republic of China regarding the establishment of a quality standard system for TCM medicinal materials. Methods:Based on the requirements of DPC, and referring to the relevant methods of Pharmacopoeia of the People's Republic of China, the quality of 30 batches of Descurainiae Semen samples were assessed by observing the appearance and microscopic characteristics and determining their loss on drying, total ash content, and ash insoluble in hydrochloric acid. A TLC identification method was established based on a silica gel G TLC plate, using a developing agent composed of ethyl acetate, formic acid, and water in the ratio of 7:1.5:2.5 ( V/ V/ V). The method utilized rutin and quercetin as indicators for the System Suitability Test (SST), and took quercetin-3-O-β-D-glucose-7-O-β-D-gentiobioside and isorhamnetin 3-O-β-D-glucose-7-O-β-D-gentiobioside as the index. Based on the content determination method for Descurainiae Semen in the Pharmacopoeia of the People's Republic of China, a content determination method was established with quercetin-3-O-β-D-glucose-7-O-β- D-gentiobioside as the index. Results:The loss on drying for the 30 batches of samples ranged from 6.15% to 12.0%, with the total ash content ranged from 3.17% to 9.44%, and the ash insoluble in hydrochloric acid content ranged from 0.14% to 4.82%. The resolution of rutin and quercetin met the DPC's requirements for the SST criteria in TLC identification, and all batches of samples showed good separation of the index components. This method could effectively distinguish Descurainiae Semen from Lepidii Semen. Using modern chromatographic and spectroscopic techniques, the structure of the chromatographic peak adjacent to the component of the index (quercetin-3-O-β- D-glucoside-7-O-β-D-gentiobioside) was identified as descuraic anhydride B. The resolution between the two components in all batches of samples was greater than 3.1, which met the DPC's requirements for the SST criteria in content determination. The results of the methodological investigations met the requirements for content determination. The content of quercetin-3-O-β- D-glucose-7-O-β-D-gentiobioside in 30 batches of samples ranged from 0.062%-0.125%.Conclusion:The established quality standard system for Descurainiae Semen in this article is comprehensive, and meets the requirements of the DPC, which can be used for the quality control of Descurainiae Semen.