Natural Deep Eutectic Solvents for the Extraction of Bioactive Steroidal Saponins from Dioscoreae Nipponicae Rhizoma.

In the present study, a simple and environmentally friendly extraction method based on natural deep eutectic solvents (NADESs) was established to extract four bioactive steroidal saponins from Dioscoreae Nipponicae Rhizoma (DNR). A total of twenty-one types of choline chloride, betaine, and L-proline based NADESs were tailored, and the NADES composed of 1:1 molar ratio of choline chloride and malonic acid showed the best extraction efficiency for the four steroidal saponins compared with other NADESs. Then, the extraction parameters for extraction of steroidal saponins by selected tailor-made NADES were optimized using response surface methodology and the optimal extraction conditions are extraction time, 23.5 min; liquid-solid ratio, 57.5 mL/g; and water content, 54%. The microstructure of the DNR powder before and after ultrasonic extraction by conventional solvents (water and methanol) and the selected NADES were observed using field emission scanning electron microscope. In addition, the four steroidal saponins were recovered from NADESs by D101 macroporous resin with a satisfactory recovery yield between 67.27% and 79.90%. The present research demonstrates that NADESs are a suitable green media for the extraction of the bioactive steroidal saponins from DNR, and have a great potential as possible alternatives to organic solvents for efficiently extracting bioactive compounds from natural products.

The aqueous extract of Gentianella acuta improves isoproterenol­induced myocardial fibrosis via inhibition of the TGF­ß1/Smads signaling pathway.

Gentianella acuta (G. acuta) is one of the most commonly used herbs in Chinese Mongolian medicine for the treatment of heart disease. Previously, it was found that G. acuta ameliorated cardiac function and inhibited isoproterenol (ISO)­induced myocardial fibrosis in rats. In this study, the underlying anti­fibrotic mechanism of G. acuta was further elucidated. Histopathological changes in the heart were observed by hematoxylin­eosin, Masson trichrome and wheat germ agglutinin staining. Relevant molecular events were investigated using immunohistochemistry and western blotting. The results revealed that G. acuta caused improvements in myocardial injury and fibrosis. G. acuta also inhibited collagens I and III and α­smooth muscle actin production in heart tissue. G. acuta downregulated the expression of transforming growth factor ß1 (TGF­ß1) and notably inhibited the levels of phosphorylation of TGF­ß receptors I and II. Furthermore, G. acuta caused downregulation of the intracellular mothers against decapentaplegic homolog (Smads)2 and 4 expression and inhibited Smads2 and 3 phosphorylation. The results further demonstrated that the mechanism underlying anti­myocardial fibrosis effects of G. acuta was based upon the suppression of the TGF­ß1/Smads signaling pathway. Therefore, G. acuta may be a potential therapeutic agent for ameliorating myocardial fibrosis.

Chelidonine enhances the antitumor effect of lenvatinib on hepatocellular carcinoma cells.

BACKGROUND: Lenvatinib is a newly approved molecular targeted drug for the treatment of advanced hepatocellular carcinoma (HCC). However, the high cost associated with this treatment poses a huge financial burden on patients and the entire public health system. Therefore, there is an urgent need to develop novel strategies that enhance the antitumor effect of lenvatinib. METHODS: The antitumor effects of chelidonine or/and lenvatinib on HCC cell lines MHCC97-H and LM-3 were examined using the 3-[4,5-dimethyl-2-thiazolyl]-2,5-diphenyl-2- H-tetrazolium bromide (MTT) assay. For the in-vivo investigation, the effect on subcutaneous or intrahepatic tumor growth in nude mice was also determined. The mRNA levels of epithelial mesenchymal transition (EMT)-related factors were examined through quantitative polymerase chain reaction or Western blot. RESULTS: In the present study, we found that treatment with chelidonine enhanced the apoptotic effect of lenvatinib on HCC cells and the in-vivo growth of HCC tumors in nude mice. Mechanistically, treatment with chelidonine increased the expression of epithelial indicator E-cadherin, whereas it decreased the expression of mesenchymal indicators N-cadherin and Vimentin. These findings suggest that chelidonine restricted the EMT in HCC cells. CONCLUSION: Chelidonine inhibits the process of EMT and enhances the antitumor effect of lenvatinib on HCC cells.

Roscovitine attenuates intimal hyperplasia via inhibiting NF-κB and STAT3 activation induced by TNF-α in vascular smooth muscle cells.

Roscovitine is a selective CDK inhibitor originally designed as anti-cancer agent, which has also been shown to inhibit proliferation in vascular smooth muscle cells (VSMCs). However, its effect on vascular remodeling and its mechanism of action remain unknown. In our study, we created a new intimal hyperplasia model in male Sprague-Dawley rats by trypsin digestion method, which cause to vascular injury as well as the model of rat carotid balloon angioplasty. Roscovitine administration led to a significant reduction in neointimal formation and VSMCs proliferation after injury in rats. Western blot analysis revealed that, in response to vascular injury, TNF-α stimulation induced p65 and STAT3 phosphorylation and promoted translocation of these molecules into the nucleus. p65 can physically associate with STAT3 and bind to TNF-α-regulated target promoters, such as MCP-1 and ICAM-1, to initiate gene transcription. Roscovitine can interrupt activation of NF-κB and reduce expression of TNF-α-induced proinflammatory gene, thus inhibiting intimal hyperplasia. These findings provide a novel mechanism to explain the roscovitine-mediated inhibition of intimal hyperplasia induced by proinflammatory pathways.