Objective To explore the hepatotoxicity of Dioscoreae Bulbiferae Rhizoma and its molecular mechanism using transcriptomics.Methods Totally 40 SPF-grade male Kunming mice were randomly divided into the normal control group and Dioscoreae Bulbiferae Rhizoma low-,medium-and high-dosage groups,and were orally administered with the decoction of Dioscoreae Bulbiferae Rhizoma for 14 days.Serum alanine aminotransferase(ALT)and aspartate aminotransferase(AST)contents were detected,HE staining was used for morphology examination of the liver and scoring,transcriptomic analysis was conducted to detect the gene expression of liver tissue,differentially expressed genes were subjected to GO and KEGG pathway enrichment analysis,serum alkaline phosphatase(ALP)and total bile acid(TBA)content in liver tissue were detected,Western blot was used to validate key targets.Results Compared with the normal control group,Dioscoreae Bulbiferae Rhizoma high-dosage group showed an increase in serum ALT and AST contents(P<0.05),with hepatic cell edema,increased volume,dilated hepatic sinusoids,necrosis in some areas,and elevated pathological score(P<0.05).Transcriptomic analysis revealed that after intervention with Dioscoreae Bulbiferae Rhizoma,differentially expressed genes in liver tissue were mainly enriched in cholesterol metabolism process,steroid metabolism process,cholesterol biosynthesis process,and signaling pathways such as steroid biosynthesis,cholesterol metabolism,bile secretion and primary bile acid biosynthesis.The experimental verification results showed that serum ALP and liver tissue TBA content in Dioscoreae Bulbiferae Rhizoma high-dosage group increased(P<0.05),as well as HMGCS1 and CYP51A1,the expressions of CYP27A1 and CYP7A1,which promoted cholesterol conversion to bile acids in liver tissue increased(P<0.05,P<0.01),while the expression of multidrug resistance protein 4(MRP4),which promoted bile acid excretion decreased(P<0.05).Conclusion Dioscoreae Bulbiferae Rhizoma inducing liver toxicity is related to promoting cholesterol synthesis and conversion into bile acids,while inhibiting bile acid excretion.

Objective To explore the hepatotoxicity of Dioscoreae Bulbiferae Rhizoma and its molecular mechanism using transcriptomics.Methods Totally 40 SPF-grade male Kunming mice were randomly divided into the normal control group and Dioscoreae Bulbiferae Rhizoma low-,medium-and high-dosage groups,and were orally administered with the decoction of Dioscoreae Bulbiferae Rhizoma for 14 days.Serum alanine aminotransferase(ALT)and aspartate aminotransferase(AST)contents were detected,HE staining was used for morphology examination of the liver and scoring,transcriptomic analysis was conducted to detect the gene expression of liver tissue,differentially expressed genes were subjected to GO and KEGG pathway enrichment analysis,serum alkaline phosphatase(ALP)and total bile acid(TBA)content in liver tissue were detected,Western blot was used to validate key targets.Results Compared with the normal control group,Dioscoreae Bulbiferae Rhizoma high-dosage group showed an increase in serum ALT and AST contents(P<0.05),with hepatic cell edema,increased volume,dilated hepatic sinusoids,necrosis in some areas,and elevated pathological score(P<0.05).Transcriptomic analysis revealed that after intervention with Dioscoreae Bulbiferae Rhizoma,differentially expressed genes in liver tissue were mainly enriched in cholesterol metabolism process,steroid metabolism process,cholesterol biosynthesis process,and signaling pathways such as steroid biosynthesis,cholesterol metabolism,bile secretion and primary bile acid biosynthesis.The experimental verification results showed that serum ALP and liver tissue TBA content in Dioscoreae Bulbiferae Rhizoma high-dosage group increased(P<0.05),as well as HMGCS1 and CYP51A1,the expressions of CYP27A1 and CYP7A1,which promoted cholesterol conversion to bile acids in liver tissue increased(P<0.05,P<0.01),while the expression of multidrug resistance protein 4(MRP4),which promoted bile acid excretion decreased(P<0.05).Conclusion Dioscoreae Bulbiferae Rhizoma inducing liver toxicity is related to promoting cholesterol synthesis and conversion into bile acids,while inhibiting bile acid excretion.

OBJECTIVES: Liver disease is the most common extra-intestinal manifestation of ulcerative colitis (UC), but the underlying pathogenesis is still not clarified. It is well accepted that the occurrence of UC-related liver disease has close correlation with immune activation, intestinal bacterial liver translocation, inflammatory cytokine storm, and the disturbance of bile acid circulation. The occurrence of UC-related liver disease makes the therapy difficult, therefor study on the pathogenesis of UC-related liver injury is of great significance for its prevention and treatment. Glutathione (GSH) shows multiple physiological activities, such as free radical scavenging, detoxification metabolism and immune defense. The synthesis and the oxidation-reduction all contribute to GSH antioxidant function. It is reported that the deficiency in hepatic GSH antioxidant function participates in multiple liver diseases, but whether it participates in the pathogenesis of UC-related liver injury is still not clear. This study aims to investigate the feature and underlying mechanism of GSH synthesis and oxidation-reduction function during the development of UC, which will provide useful information for the pathogenesis study on UC-related liver injury. METHODS: UC model was induced by 2,4,6-trinitrobenzenesulfonic acid (TNBS)-ethanol solution (5 mg/0.8 mL per rat, 50% ethanol) via intra-colonic administration in rats, and the samples of serum, liver, and colon tissue of rats were collected at the 3rd, 5th, and 7th days post TNBS. The severity degree of colitis was evaluated by measuring the disease activity index, colonic myeloperoxidase activity, and histopathological score, and the degree of liver injury was evaluated by histopathological score and the serum content of alanine aminotransferase. Spearman correlation analysis was also conducted between the degree of colonic lesions and index of hepatic histopathological score as well as serum aspartate aminotransferase level to clarify the correlation between liver injury and colitis. To evaluate the hepatic antioxidant function of GSH in UC rats, hepatic GSH content, enzyme activity of GSH peroxidase (GSH-Px), and GSH reductase (GR) were determined in rats at the 3rd, 5th, and 7th days post TNBS, and the protein expressions of glutamine cysteine ligase (GCL), GSH synthase, GSH-Px, and GR in the liver of UC rats were also examined by Western blotting. RESULTS: Compared with the control, the disease activity index, colonic myeloperoxidase activity, and histopathological score were all significantly increased at the 3rd, 5th, and 7th days post TNBS (all P<0.01), the serum aspartate aminotransferase level and hepatic histopathologic score were also obviously elevated at the 7th day post TNBS (all P<0.05). There was a significant positive correlation between the degree of liver injury and the severity of colonic lesions (P=0.000 1). Moreover, compared with the control, hepatic GSH content and the activity of GSH-Px and GR were all significantly decreased at the 3rd and 5th days post TNBS (P<0.05 or P<0.01), and the protein expressions of GCL, GSH-Px, and GR were all obviously down-regulated at the 3rd, 5th, and 7th days post TNBS (P<0.05 or P<0.01). CONCLUSIONS There is a significant positive correlation between the degree of liver injury and the severity of colonic lesions, and the occurrence of reduced hepatic GSH synthesis and decreased GSH reduction function is obviously earlier than that of the liver injury in UC rats. The reduced hepatic expression of enzymes that responsible for GSH synthesis and reduction may contribute to the deficiency of GSH synthesis and oxidation-reduction function, indicating that the deficiency in GSH antioxidant function may participate in the pathogenesis of UC related liver injury.
Animals ; Antioxidants ; Aspartate Aminotransferases ; Colitis/chemically induced* ; Colitis, Ulcerative/metabolism* ; Colon/pathology* ; Glutathione/biosynthesis* ; Liver/metabolism* ; Peroxidase/metabolism* ; Rats ; Trinitrobenzenesulfonic Acid