Inhibition of pathological angiogenesis of Chinese medicine against liver fibrosis

Network Pharmacological Analysis and Experimental Validation of the Mechanisms of Action of Si-Ni-San Against Liver Fibrosis

Background: Si-Ni-San (SNS), a commonly used traditional Chinese medicine (TCM) formula, has potency against liver diseases, such as hepatitis and non-alcoholic fatty liver disease (NAFLD). However, the therapeutic efficacy and pharmacological mechanisms of action of SNS against liver fibrosis remain largely unclear. Methods: A carbon tetrachloride (CCl4)-induced liver fibrosis mouse model was adopted for the first time to investigate the beneficial effects of SNS on liver fibrosis. The potential mechanisms of action of SNS were explored using the network pharmacology-based strategy and validated with the aid of diverse assays. Results: SNS treatment reduced collagen and ECM deposition, downregulated fibrosis-related factor (hyaluronic acid and laminin) contents in serum, maintained the morphological structure of liver tissue, and improved liver function in the liver fibrosis model. Based on network pharmacology results, apoptosis, inflammation and angiogenesis, together with the associated pathways (including VEGF, TNF, caspase, PPAR-γ and NF-κB), were identified as the mechanisms underlying the effects of SNS on liver fibrosis. Further in vivo experiments validated the significant mitigatory effects of SNS on inflammatory infiltration and pro-inflammatory cytokine contents (IFNγ, IL-1β and TGF-β1) in liver tissues of mice with liver fibrosis. SNS suppressed pathologic neovascularization as well as levels of VEGFR1, VEGF and VEGFR2 in liver tissues. SNS treatment additionally inhibited hepatic parenchyma cell apoptosis in liver tissues of mice with liver fibrosis and regulated apoptin expression while protecting L02 cells against apoptosis induced by TNF-α and Act D in vitro. Activation of hepatic stellate cells was suppressed and the balance between MMP13 and TIMP1 maintained in vitro by SNS. These activities may be associated with SNS-induced NF-κB suppression and PPAR-γ activation. Conclusion: SNS effectively impedes liver fibrosis progression through alleviating inflammation, ECM accumulation, aberrant angiogenesis and apoptosis of hepatic parenchymal cells along with inhibiting activation of hepatic stellate cells through effects on multiple targets and may thus serve as a novel therapeutic regimen for this condition.

[Inhibitory effect of Xinhui citrus fermentation liquor on liver fibrosis in mice]

OBJECTIVE

To investigate the inhibitory effect of Xinhui citrus fermentation liquor on liver fibrosis in mice.

OBJECTIVE

Mouse models of liver fibrosis were established by intraperitoneal injection of CCl₄ in 105 male C57BL/6 mice, followed by gavage of 0.1 mL 40% CCl₄ olive oil 3 times a week (model group, n=49) or daily gavage of citrus liquor at the dose of 0.26 mL (citrus liquor group, n=56) for 8 weeks. Seven mice receiving only olive oil treatment (0.1 mL, 3 times a week) and another 7 treated with citrus liquor served as the control group. Liver tissues and serum samples were collected from 7 mice in the citrus liquor group and model group each week and from the mice in the two control groups at the 8th week for pathological examination of the liver tissues using HE staining and Sirius red staining and for determination of the biochemical indexes of liver function.

OBJECTIVE

The mice in the model group showed progressively worsened liver fibrosis with obvious hepatic steatosis, necrosis and inflammatory cell infiltration. These liver pathologies were much ameliorated in citrus liquor group, which showed significantly reduced vacuolation, inflammatory cell infiltration, collagen deposition and the Ishak score of the liver tissue (P < 0.05). Serum levels of cholyglycine, alanine aminotransferase, transglutaminase and alanine aminotransferase were all significantly lower in citrus liquor group than in the model group (P < 0.05).

OBJECTIVE

Xinhui citrus fermentation liquor has protective effect on the liver and can significantly ameliorate liver fibrosis in mice.

Systems Pharmacology Study of the Anti-Liver Injury Mechanism of Citri Reticulatae Pericarpium

Liver diseases are mostly triggered by oxidative stress and inflammation, leading to extracellular matrix overproduction and prone to develop into liver fibrosis, cirrhosis and hepatocellular carcinoma. Liver injury (LI) refers to various pathogenic factors leading to the destruction of stem cells that then affect the liver's normal function, causing a series of symptoms and abnormal liver function indicators. Citri Reticulatae Pericarpium (CRP) is one of the most commonly used traditional Chinese medicines; it contains flavonoids including hesperidin, nobiletin, and tangeretin. CRP has antibacterial, antioxidant, and antitumor effects that reduce cholesterol, prevent atherosclerosis and decrease LI. Here we analyzed the components of CRP and their targets of action in LI treatment and assessed the relationships between them using a systems pharmacology approach. Twenty-five active ingredients against LI were selected based on ultra-performance liquid chromatography-quadrupole/time-of-flight mass spectrometry results and databases. The drug targets and disease-related targets were predicted. The 117 common targets were used to construct a protein-protein interaction network. We identified 1719 gene ontology items in LI treatment, including 1,525 biological processes, 55 cellular components, and 139 molecular functions. These correlated with 49 Kyoto Encyclopedia of Genes and Genomes pathways. These findings suggest that CRP may counteract LI by affecting apoptotic, inflammatory, and energy metabolism modules. In vitro experiments suggested that the mechanism may involve hesperidin and naringenin acting on CASP3, BAX, and BCL2 to affect the apoptosis pathway, attenuating liver fibrosis. Naringenin significantly inhibited AKT1 phosphorylation, which in turn mediated activation of the phosphoinositide 3-kinase-Akt signaling pathways against LI. This study provides a reference for systematically exploring the mechanism of CRP's anti-LI action and is also expands of the application of systems pharmacology in the study of traditional Chinese medicine.

Anti-fibrotic Effects and Mechanism of Shengmai Injection () on Human Hepatic Stellate Cells LX-2

OBJECTIVE

To investigate the effects of Shengmai Injection (, SMI) on the proliferation, apoptosis and N-myc downstream-regulated gene 2 (NDRG2, a tumour suppressor gene) expression in varying densities of human hepatic stellate cells LX-2.

METHODS

LX-2 cells were cultured in vitro. Then, cells were plated in 96-well plates at an approximate density of 2.5×10⁴ cells/mL and cultured for 48, 72, 96 or 120 h followed by the application of different concentrations of SMI (0.6, 1.2, 2.4, 4.8 or 6 μL/mL). Cell proliferation was measured after an additional 24 or 48 h using the 3(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The effects of SMI on different cell growth states (cultured for 48, 72, 96, or 120 h) were observed by light microscopy at 24 h after treatment. When the cells reached 80% conflfluence, apoptosis was detected by flflow cytometry after 24 h. Lastly, LX-2 cells were treated with different concentrations of SMI and extracted with protein lysis buffer. The levels of NDRG2 were measured by Western blot.

RESULTS

When the LX-2 cells grew for 48, 72, 96 and 120 h, 4.8 and 6 μL/mL of SMI significantly inhibited cell proliferation at 24 and 48 h after treatment (P<0.05). And 2.4 μL/mL of SMI also inhibited cell proliferation at 24 h after treatment when cell growth for 48 h (P<0.05) and at 48 h after treatment when cell growth for 72, 96 and 120 h (P<0.05). The NDRG2 expression level in the LX-2 cell was significantly increased when treated with SMI at concentrations of 1.2, 2.4, 4.8 or 6 μL/mL (P<0.05).

CONCLUSION

The inhibitory effects of SMI on the proliferation of LX-2 cells were related to not only concentration dependent but also cell density. In addition, SMI (2.4, 4.8 and 6 μL/mL) could accelerate apoptosis in LX-2 cells, and the mechanism might be associated with NDRG2 over-expression.

Levistilide A inhibits angiogenesis in liver fibrosis via vascular endothelial growth factor signaling pathway

Levistilide A (C₂₄H₂₈O₄, molecular weight = 380.48) derived from Angelica sinensis (Danggui) has been reported to inhibit hepatic stellate cell proliferation. This study investigated the effects of levistilide A on liver fibrosis relating to angiogenesis, particularly on the characteristic change in liver sinusoidal endothelial cells. LX-2 cells were activated by TGF-β1, and the human hepatic sinusoidal endothelial cells (HHSECs) were induced by endothelial cell growth supplement. Cell viability was detected using a methylthiazoldiphenyl-tetrazolium bromide assay; F-actin was visualized through the fluorescence probe method; cell proliferation was examined using the EdU kit; antiangiogenesis activity was assessed using the tube formation assay and transgenic zebrafish model. To verify the results in vivo, rats were subcutaneously injected with CCl₄ twice a week for six weeks to duplicate the liver fibrosis model and then treated with 10 mL/kg of normal saline, 4 mg/kg of sorafenib, and 3 and 6 mg/kg of levistilide A for three weeks from the fourth week. Collagen deposition was detected through Sirius Red staining; liver microvasculature was examined through vWF labeling and X-ray 2D imaging; sinusoidal fenestrations were observed through scanning electron microscopy; collagen I, α-SMA, CD31, vascular endothelial growth factor (VEGF), and VEGF-R2 were detected through Western blotting. Our results indicated that levistilide A attenuated LX-2 cell activation and HHSEC proliferation. The ability of HHSECs to form tubelike structures in Matrigel was inhibited, and the number of functional vessels in transgenic zebrafish decreased. In in vivo experiments, levistilide A reduced collagen deposition and the number of new microvessels; ameliorated sinusoid capillarization; and downregulated the expression of CD31, VEGF, and VEGF-R2. These findings suggest that levistilide A can inhibit liver fibrosis through antiangiogenesis by alleviating sinusoid capillarization via the VEGF signaling pathway. Impact statement Levistilide A has been reported to inhibit hepatic stellate cell (HSC) proliferation. In this study, we further investigated the mechanisms of levistilide A on liver fibrosis relating to angiogenesis, particularly on the characteristic change in liver sinusoidal endothelial cells. The cell models of HSC and liver sinusoidal endothelial cell and CCl₄ induced liver fibrosis model were used. These results suggest that levistilide A can inhibit liver fibrosis through antiangiogenesis by alleviating sinusoid capillarization via the vascular endothelial growth factor signaling pathway. The effect of levistilide A on liver fibrosis was confirmed, and its detailed mechanism was also discussed. These findings suggest that levistilide A may be a great potential drug for treating liver fibrosis through antiangiogenesis, and this effect will be verified in other fibrotic animal model studies or by clinical trials.