[Discussion on hepatic damage mechanism of Asari Radix et Rhizoma based on network pharmacology and untargeted metabolomics].

Asari Radix et Rhizoma is a common drug for relieving exterior syndrome in clinics, but its toxicity limits its use. In this study, the mechanism of hepatic damage of Asari Radix et Rhizoma was studied by network pharmacology and metabolomics. The hepatic damage-related dataset, namely GSE54257 was downloaded from the GEO database. The Limma package was used to analyze the differentially expressed genes in the dataset GSE54257. Toxic components and target genes of Asari Radix et Rhizoma were screened by TCMSP, ECTM, and TOXNET. The hepatic damage target genes of Asari Radix et Rhizoma were obtained by mapping with the differentially expressed gene of GSE54257, and a PPI network was constructed. GO and KEGG enrichment analysis of target genes were performed, and a "miRNA-target gene-signal pathway" network was drawn with upstream miRNA information. Thirty rats were divided into a blank group, a high-dose Asari Radix et Rhizoma group, and a low-dose Asari Radix et Rhizoma group, which were administered once a day. After continuous administration for 28 days, liver function indexes and liver pathological changes were detected. Five liver tissue samples were randomly collected from the blank group and high-dose Asari Radix et Rhizoma group, and small molecule metabolites were analyzed by ultra-high performance liquid chromatography-mass spectrometry(UHPLC-MS). The orthogonal partial least squares-discriminant analysis(OPLS-DA) method was used to screen differential metabolites, and enrichment analysis, correlation analysis, and cluster analysis were conducted for differential metabolites. Finally, the MetaboAnalyst platform was used to conduct pathway enrichment analysis for differential metabolites. It was found that there were 14 toxic components in Asari Radix et Rhizoma, corresponding to 37 target genes, and 12 genes related to liver toxicity of Asari Radix et Rhizoma were obtained by mapping to differentially expressed genes of GSE54257. The animal test results showed that Asari Radix et Rhizoma could significantly increase the liver function index, reduce the activity of the free radical scavenging enzyme, change the liver oxidative stress level, and induce lipid peroxidation damage in rats. The results of untargeted metabolomics analysis showed that compared with the blank group, nine metabolites were up-regulated, and 16 metabolites were down-regulated in the liver tissue of the Asari Radix et Rhizoma group. These 25 metabolites had strong correlations and good clustering. Pathway enrichment analysis showed that these differential metabolites and the 12 hepatotoxic target genes of Asari Radix et Rhizoma were mainly involved in purine metabolism, as well as the biosynthesis and metabolism of valine, leucine, glycine, serine, and threonine. The study confirmed that the hepatica damage effect of Asari Radix et Rhizoma was the result of multi-component, multi-target, and multi-signaling pathways, and its mechanism may be related to inhibiting nucleotide synthesis and affecting protein metabolism.