Effect of thalidomide on the expression of vascular endothelial growth factor in a rat model of liver regeneration

Angelica sinensis Polysaccharide and Astragalus membranaceus Polysaccharide Accelerate Liver Regeneration by Enhanced Glycolysis via Activation of JAK2/STAT3/HK2 Pathway

The promotion of liver regeneration is crucial to avoid liver failure after hepatectomy. Angelica sinensis polysaccharide (ASP) and Astragalus membranaceus polysaccharide (AMP) have been identified as being associated with hepatoprotective effects. However, their roles and specific mechanisms in liver regeneration remain to be elucidated. In the present study, it suggested that the respective use of ASP or AMP strikingly promoted hepatocyte proliferation in vitro with a wide range of concentrations (from 12.5 μg/mL to 3200 μg/mL), and a stronger promoting effect was observed in combined interventions. A significantly enhanced liver/body weight ratio (4.20%) on day 7 and reduced serum transaminase (ALT 243.53 IU/L and AST 423.74 IU/L) and total bilirubin (52.61 IU/L) levels on day 3 were achieved by means of ASP-AMP administration after partial hepatectomy in mice. Metabonomics showed that differential metabolites were enriched in glycolysis with high expression of beta-d-fructose 6-phosphate and lactate, followed by significantly strengthened lactate secretion in the supernatant (0.54) and serum (0.43) normalized to control. Upon ASP-AMP treatment, the knockdown of hexokinase 2 (HK2) or inhibited glycolysis caused by 2-deoxy-d-glucose decreased hepatocyte proliferation in vitro and in vivo. Furthermore, pathway analysis predicted the role of JAK2/STAT3 pathway in ASP-AMP-regulated liver regeneration, and phosphorylation of JAK2 and STAT3 was proven to be elevated in this promoting process. Finally, downregulated expression of HK2, an attenuated level of lactate secretion, and reduced hepatocyte proliferation were displayed when STAT3 was knocked out in vitro. Therefore, it can be concluded that ASP-AMP accelerated liver regeneration and exerted a hepatoprotective effect after hepatectomy, in which the JAK2/STAT3/HK2 pathway was actively involved in activating glycolysis.

Thalidomide Accelerates the Degradation of Extracellular Matrix in Rat Hepatic Cirrhosis via Down-Regulation of Transforming Growth Factor-β1

PURPOSE

The degradation of the extracellular matrix has been shown to play an important role in the treatment of hepatic cirrhosis. In this study, the effect of thalidomide on the degradation of extracellular matrix was evaluated in a rat model of hepatic cirrhosis.

MATERIALS AND METHODS

Cirrhosis was induced in Wistar rats by intraperitoneal injection of carbon tetrachloride (CCl₄) three times weekly for 8 weeks. Then CCl₄ was discontinued and thalidomide (100 mg/kg) or its vehicle was administered daily by gavage for 6 weeks. Serum hyaluronic acid, laminin, procollagen type III, and collagen type IV were examined by using a radioimmunoassay. Matrix metalloproteinase-13 (MMP-13), tissue inhibitor of metalloproteinase-1 (TIMP-1), and α-smooth muscle actin (α-SMA) protein in the liver, transforming growth factor β1 (TGF-β1) protein in cytoplasm by using immunohistochemistry and Western blot analysis, and MMP-13, TIMP-1, and TGF-β1 mRNA levels in the liver were studied using reverse transcriptase polymerase chain reaction.

RESULTS

Liver histopathology was significantly better in rats given thalidomide than in the untreated model group. The levels of TIMP-1 and TGF-β1 mRNA and protein expressions were decreased significantly and MMP-13 mRNA and protein in the liver were significantly elevated in the thalidomide-treated group.

CONCLUSION

Thalidomide may exert its effects on the regulation of MMP-13 and TIMP-1 via inhibition of the TGF-β1 signaling pathway, which enhances the degradation of extracellular matrix and accelerates the regression of hepatic cirrhosis in rats.

Extracts of endophytic fungus xkc-s03 from Prunella vulgaris L. spica inhibit gastric cancer in vitro and in vivo

Prunella vulgaris L. belongs to the Prunella genus and has been proven effective in the treatment of gastric cancer, however, the therapeutic activity of the endophytic fungi is not yet well understood. The results of the present study suggest that the ethyl acetate extract (S03-EA) of the endophytic fungus XKC-S03, isolated from Prunella vulgaris L. spica, is a potent anticancer agent with the potential to treat gastric cancer. In the present study, the effects of S03-EA on gastric cancer in vitro and in vivo were determined using the 1-(4,5-dimethylthiazol-2-yl)-3,5-diphenylformazan assay and the human gastric cancer SGC 7901 cell xenograft model. The tumor tissue was fixed with 10% formaldehyde solution and the levels of the apoptotic proteins, B-cell lymphoma protein-2 (Bcl-2), Bcl-2-associated X protein (Bax) and pro-angiogenic vascular endothelial growth factor (VEGF), were measured by immunohistochemistry. The results indicated that treating SGC 7901 cells with petroleum ether (S03-PE), ethyl acetate (S03-EA) or dichloromethane (S03-DM) extracts from the XKC-S03 fermentation broth inhibited cell proliferation. S03-EA demonstrated the best activity, with a half maximal inhibitory concentration of 25.89 μg/ml and dose-dependent suppression of the SGC 7901 tumor cells in vivo, without any evident adverse effects. In addition, the 100-mg/kg/day S03-EA-treated tumor tissue revealed a downregulation of Bcl-2 and VEGF expression and an upregulation of Bax expression. In conclusion, the S03-EA extract of XKC-S03, isolated from Prunella vulgaris L. spica, exhibits a growth-suppressive activity on gastric cancer in vitro and in vivo.