Hepatoprotective effects of Cassiae Semen on mice with non-alcoholic fatty liver disease based on gut microbiota

Cassiae Semen (CS), the seeds of Cassia obtusifolia L. and C. tora L, have a long medicinal history in China, with suggestions for it to relieve constipation and exert hepatoprotective effects. However, the underlying mechanisms are still unclear. In this study, mice with high-fat diet (HFD)-induced non-alcoholic fatty liver disease (NAFLD) were used to study the hepatoprotective effects of CS. The relationship between gut microbiota and hepatoprotective effect mechanisms mediated by CS extracts, the total aglycone extracts of CS, rubrofusarin-6-β-gentiobioside, and aurantio-obtusin were examined. Our data indicate that CS extracts and components confer a protective effect by ameliorating lipid accumulation, intestinal barrier damage, liver damage, and inflammation on HFD-induced liver injury. Meanwhile, fecal microbe transplantation exerted the pharmacological effect of CS on HFD-fed mice; however, the efficacy of CS was inhibited or eliminated by antibiotic-induced dysbiosis. In conclusion, the therapeutic effects of CS on NAFLD were closely related to the gut microbiota, suggesting a role for TCM in treating disease.


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Animals were housed in a controlled environment (12 h/light-dark cycle at 20-22 ‫خ‬ and 45±5% humidity), with free access to food and water. The control group (10 mice) was fed a normal diet (12.0% energy from fat). In total, 150 mice were fed a high-fat diet (15% lard, 2.5% cholesterol, 0.5% bile salts, 15% dextrin, and 67% basal feed) for 17 weeks to generate an NAFLD model. From week 14, control and model group mice were supplemented daily with 300 µL sterile saline. The administration groups were given: JMZ (10 g/kg), TA (10 g/kg), RG (20 mg/kg), and AO (20 mg/kg) by intragastric gavage once a day. After three weeks (21 days) treatment, whole bloods were collected from the ophthalmic venous plexus, and serum was separated for serum marker quantification. Mice were sacrificed by cervical spondylolisthesis, with liver and ileum tissue extracted.
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