epidermal-growth-factor and tanshinone

Natural products present in low quantity in herb medicines constitute an important source of chemical diversity. However, the isolation of sufficient amounts of these low abundant constituents for structural modification has been a challenge for several decades and subsequently halts research on the utilization of this important source of chemical entities for drug discovery and development. And, pro-angiogenic therapies are being explored as options to treat cardio-cerebral vascular diseases and wound healing recently. The present study investigates the pro-angiogenic potential of tanshinone derivatives produced by one-pot synthesis using zebrafish model.. In order to address the difficulty of chemical modification of low abundant constituents in herb medicines, a novel one-pot combinatorial modification was used to diversify a partially purified tanshinone mixture from Salvia miltiorrhiza. This led to the isolation of ten new imidazole-tanshinones (Compounds 1-10) and one oxazole-tanshinone (Compound 11), the structures of which were characterized by spectroscopic methods in combination with single-crystal X-ray crystallographic analysis. The angiogenesis activities of the new tanshinone derivatives were determined in an experimental model of chemical-induced blood vessels damage in zebrafish. Of all the tested new derivatives, compound 10 exhibited the most potent vascular protective and restorative activity with an EC50 value of 0.026 µM. Moreover, the mechanism underlying the pro-angiogenesis effect of 10 probably involved the VEGF/FGF-Src-MAPK and PI3K-P38 signalling pathways by gene expression analysis and a blocking assay with pathways-specific kinase inhibitors.. Taken together, our study demonstrated the more distinctive pro-angiogenic properties of 10 than other tanshinones and revealed 10 has potential for development as a pro-angiogenic agent for diseases associated with insufficient angiogenesis. Our results highlighted the great potential of adopting a newly modified one-pot approach to enhance the chemical diversity and biological activities of constituents from natural products regardless of their abundances.

Topics: Abietanes; Animals; Cell Proliferation; Embryo, Nonmammalian; Epidermal Growth Factor; Fibroblast Growth Factors; Humans; MCF-7 Cells; Models, Biological; Neovascularization, Physiologic; Plant Preparations; Salvia miltiorrhiza; Signal Transduction; Zebrafish

To observe the effect of Tanshinone II A on the expression of epidermal growth facter (EGF) and epidermal growth facter recepter (EGFR) in human hepatocellular carcinoma cell line SMMC-7721.. The human hepatocellular carcinoma SMMC-7721 cells cultured in vitro was treated with different concentrations of Tanshinone II A. The proliferation of the cells was measured by MTT assay, and the apoptosis of the cells was investigated by flow cytometry and cytochemical staining with Hoechst 33342. The expression of EGF and EGFR was detected by immunocytochemistry method. The levels of EGF in medium were measured by radioimmunoassay.. Tanshinone II A inhibited the growth of SMMC-7721 cells remarkably in a dose-dependent manner. The inhibitory rate reached the peak (72.5%) after 0.5 microg/ml Tanshinone II A was used for 48 h, which was significantly higher than that in the controls (P<0.05). FCM analysis showed that when SMMC-7721 cells were treated with 0.5 microg/ml Tanshinone II A, the apoptosis rates for 24 h, 48 h and 72 h were (4.06+/-0.27)%, (7.58+/-0.56)% and (5.23+/-0.13)%, respectively which were markedly higher than those in the controls (all P<0.01). SMMC-7721 cell apoptosis with cell shrinkage, nuclear chromatin concentration and fragmentation as well as the formation of apoptotic bodies were observed by cytochemical staining when treated with Tanshinone II A. The immunocytochemistry showed that the expressions of EGF and EGFR were down regulated while the concentration of Tanshinone II A was increasing. The high expression rates for EGF and EGFR were 10%, 20%, respectively, and the gray scale was 181.52+/-1.63, 179.37+/-1.59, which were markedly higher than those in the controls (all P<0.05). The levels of EGF in medium measured by radioimmunoassay were decreased significantly after Tanshinone II A treatment.. Tanshinone II A can inhibit cell proliferation and induce apoptosis in hepatocellular carcinoma cell line SMMC-7721, which may be related to the down-regulation of EGF and EGFR protein expression.

Topics: Abietanes; Antineoplastic Agents, Phytogenic; Apoptosis; Carcinoma, Hepatocellular; Cell Line, Tumor; Cell Proliferation; Down-Regulation; Epidermal Growth Factor; ErbB Receptors; Humans; Liver Neoplasms; Phenanthrenes