Protective Effect of Dandelion Jujube Juice on D-galactose-induced Liver Injury in Rats

Objective: To evaluate the protective effect and possible mechanism of dandelion jujube juice on D-galactose-induced liver injury in Sprague Dawley (SD) rats. Methods: D-galactose was intraperitoneally injected into the rats at a dose of 500 mg/kg for six weeks to establish a chronic liver injury model. These rats treated with D-galactose were then randomly divided into model group and dandelion jujube juice group (treated with 10 mL/kg·d of dandelion jujube juice by intragastric administration for 28 d). The liver index was calculated, and the pathological changes in liver tissue were observed using HE staining and oil red O staining. Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels in serum, malondialdehyde (MDA) content and catalase (CAT) activity in liver tissue were determined by corresponding assay kit. Western blot analysis was used to detect the protein expression, including Kelch like epichlorohydrin associated protein 1 (Keap1), nuclear factor E2 related factor 2 (Nrf2), heme oxygenase-1 (HO-1), BCL2 associated X (Bax), and B-cell lysoma-2 (Bcl-2) proteins in liver tissue. Results: Compared with the blank group, the liver index and liver lipid deposition area were increased in the model group. In addition, the model group showed a significant increase in the levels of serum ALT (P<0.05), AST (P<0.01), liver tissue MDA (P<0.01), Keap1 (P<0.01), Bax (P<0.01) protein expression, as well as a significant decrease in liver tissue CAT activity (P<0.01), Nrf2 (P<0.01), HO-1 (P<0.05), and Bcl-2 (P<0.01) protein expression levels, these indicate liver damage. Furthermore, in comparison with the model group, dandelion jujube juice could significantly reduce liver index (P<0.05), the levels of serum ALT (P<0.05) and AST (P<0.05), liver tissue MDA (P<0.05), Keap1 (P<0.01) protein expression, while CAT activity (P<0.05), Nrf2 (P<0.05), HO-1 (P<0.05) and Bcl-2 (P<0.01) expression in liver tissue were significantly increased. Dandelion jujube juice also significantly improved the morphology of liver tissue and reduced the number of liver cell apoptosis and the area of liver lipid deposition. Conclusion: Dandelion jujube juice may have a certain protective effect against D-galactose-induced liver injury, which may be related to activating the Keap1/Nrf2/HO-1 signaling pathway, improving liver antioxidant capacity, and inhibiting liver cell apoptosis.