Hepatoprotective Effects of Ixeris chinensis on Nonalcoholic Fatty Liver Disease Induced by High-Fat Diet in Mice: An Integrated Gut Microbiota and Metabolomic Analysis.

Ixeris chinensis (Thunb.) Nakai (IC) is a folk medicinal herb used in Mongolian medical clinics for the treatment of hepatitis and fatty liver diseases even though its pharmacological mechanism has not been well characterized. This study investigated the hepatoprotective mechanism of IC on mice with nonalcoholic fatty liver disease (NAFLD) by integrating gut microbiota and metabolomic analysis. A high-fat diet (HFD) was used to develop nonalcoholic fatty liver disease, after which the mice were treated with oral IC (0.5, 1.5 and 3.0 g/kg) for 10 weeks. HFD induced NAFLD and the therapeutic effects were characterized by pathological and histological evaluations, and the serum indicators were analyzed by ELISA. The gut microbial and metabolite profiles were studied by 16S rRNA sequencing and untargeted metabolomic analysis, respectively. The results showed that the administration of IC resulted in significant decreases in body weight; liver index; serum biomarkers such as ALT, TG, and LDL-C; and the liver inflammatory factors IL-1ß, IL-6, and TNF-α. The 16S rRNA sequencing results showed that administration of IC extract altered both the composition and abundance of the gut microbiota. Untargeted metabolomic analysis of liver samples detected a total of 212 metabolites, of which 128 were differentially expressed between the HFD and IC group. IC was found to significantly alter the levels of metabolites such as L-glutamic acid, pyridoxal, ornithine, L-aspartic acid, D-proline, and N4-acetylaminobutanal, which are involved in the regulation of glutamine and glutamate, Vitamin B6 metabolism, and arginine and proline metabolic pathways. Correlation analysis indicated that the effects of the IC extract on metabolites were associated with alterations in the abundance of Akkermansiaceae, Lachnospiraceae, and Muribaculaceae. Our study revealed that IC has a potential hepatoprotective effect in NAFLD and that its function might be linked to improvements in the composition of gut microbiota and their metabolites.

[Fingerprinting and multi-indicator quantitative analysis of Mongolian drug Digeda-4 decoction].

To establish the high performance liquid chromatography (HPLC) fingerprint for Digeda-4 decoction (DGD-4D), determine the contents of aesculetin, geniposide, picroside Ⅰ, picroside Ⅱ and ellagicacid in DGD-4D, and provide the scientific foundation for quality control of DGD-4D. The analysis was performed on Diamonsil(2) C18 (4.6 mm×250 mm,5 µm) column, with methanol-0.1% phosphoric acid aqueous solution as mobile phase for gradient elution. The flow rate was 1.0 mL·min⁻¹; injection size was 10 µL; temperature was maintained at 30 °C, and the detection wavelength was set at 254 nm. The common mode of DGD-4D HPLC fingerprint was established, and the hidden information was analyzed by Chemometrics. Chromatographic peaks for DGD-4D were identified by HPLC and quantitative analysis was conducted for characteristic peaks. There were 17 common peaks in the fingerprints and the similarity of the fingerprints was over 0.9 in all 15 batches. The samples were broadly divided into four kinds by principal component analysis and clustering analysis. Four marker compounds were verified by partial least squares discriminant analysis, and No. 9, 12 and 14 peaks were identified as geniposide, picroside Ⅱ, and picroside Ⅰ respectively. The average recoveries were in the range of 95.91%-97.31%. The HPLC fingerprint method for content determination is reliable, accurate, rapid, simple, and reproducible, and can be used as one of the effective methods to control the quality of DGD-4D.