Gynostemma pentaphyllum Attenuates the Progression of Nonalcoholic Fatty Liver Disease in Mice: A Biomedical Investigation Integrated with In Silico Assay

Figure 1. Biochemical assays and physiological parameters results of GP treatment on nonalcoholic liver disease. Treatments with GP extracts have no obvious effects on the body weight in NAFLD mice; treatment with GP extracts 0.2 g/kg/day and 0.4 g/kg/day decreased both serum ALT and AST level; GP could increase SOD, GSH-Px level in haptic tissues. In addition, MDA levels in NAFLD liver tissue were significantly increased compared with the normal group; GP extracts can alleviate the rise of MDA in mice liver (p < 0.01). #Compared with normal group p < 0.05, ∗p < 0.05, ∗∗p < 0.01, compared with model group.

Figure 2. H&E staining results after GP extracts treatment in NAFLD (original magnification 100x). (a) The normal group had a clear structure of the hepatic lobule, and there were no visible lesions. (b) In the model group, typical pathological characteristics such as inflammatory infiltration (black arrow) and macrovacuolar degeneration can be observed. ((c)–(e)) Treatment with GP (0.093, 0.28, and 0.84 g/kg) for six weeks significantly attenuated the inflammation and macrovacuolar degeneration in the liver. (f) Scoring of liver histology of NAFLD mice with GP treatment (mean ± SD). #p < 0.05, compared with normal group, and ∗p < 0.05, compared with model group.

Figure 3. Oil Red O staining results after GP extracts treatment in NAFLD (original magnification 100x). (a) The normal group had no Oil Red staining. (b) In the model group, significant Oil Red stain which indicated steatosis can be observed. (e) Treatment with GP (0.4 g/kg/day) for six weeks significantly attenuated the steatosis in the liver. (f) Scoring of steatosis histology of NAFLD mice with GP treatment (mean ± SD). #p < 0.05, compared with normal group, and ∗p < 0.05, compared with model group.

Figure 4. Picrosirius red staining results after GP extracts treatment in NAFLD (original magnification 100x). (a) The normal group had no visible Picrosirius red staining. (b) In the model group, significant Picrosirius red stain which indicated collagen deposition can be observed. (e) Treatment with GP (0.4 g/kg/day) for six weeks significantly attenuated the collagen deposition in the liver. (f) Scoring of liver fibrosis histology of NAFLD mice with GP treatment (mean ± SD). #p < 0.05, compared with normal group, and ∗p < 0.05, compared with model group.

Figure 5. Compound-target networks and active compound structures in GP. The compound-target network related to NALFD was shown in (a). The yellow triangles are active compounds from GP and the blue rectangles represent potential NAFLD target genes; the gray line represents the compound-target interaction. (b) The corresponding chemical structures of the six potential anti-NAFLD ingredients from GP.

Figure 6. Gypenoside XL attenuated haptic injury in NAFLD mice. Treatments with GP extracts have no obvious effects on the body weight in NAFLD mice; treatment with Gypenoside XL 10, 20 mg/kg/day, decreased both serum ALT and AST level; Gypenoside XL could increase SOD, GSH-Px level in haptic tissues. MDA levels in NAFLD liver tissue were significantly decreased after Gypenoside XL treatment (p < 0.01) (a). The Oil Red O, H&E, and Picrosirius red staining results showed that Gypenoside XL 10 and 20 mg/kg/day could relieve haptic fat degeneration and fibrosis in NAFLD mice (b). #Compared with normal group p < 0.05, ∗p < 0.05, ∗∗p < 0.01 compared with model group.

Figure 7. Gypenoside XL regulated PPARα expression and downstream target genes related to liver lipid metabolism. In NAFLD mice, the haptic PPARα protein level was significantly decreased after alcohol consumption. For SOX9 and BRD4 protein, the expression level was significantly increased. Gypenoside XL 10 and 20 mg/kg/day treatment led to a significant increase in PPARα protein level compared with model group (p < 0.05). However, the expression of SOX9 and BRD4 protein was not affected by GP treatment (a). CDAA diet and CCl4 exposure can lead to downregulation of ACO and CPT-1 mRNA level as well as protein level in mice liver. Gypenoside XL 10 and 20 mg/kg/day treatment can upregulate mRNA and protein levels of ACO and CPT-1 in NAFLD mice ((b), (c)). #p < 0.05, compared with normal group and ∗p < 0.05, compared with model group.

Figure 8. A flowchart of network pharmacology study of GP on NAFLD. The flowchart showed the procedures of network pharmacology study in our research. First step is building the herbal ingredients database, and then we used ADME screening to choose candidate chemicals and fishing their intracellular targets. After further NAFLD related target fishing, the data was processed by Cytoscape 3.4.0 and a network plotting was finally constructed for further analysis.