Study On Anti-angiogenesis Effects Of Albizia Different Extraction Fractions

Angiogenesis provides nutrition and mean for tumor growth and metastasis,therefore, inhibition of tumor angiogenesis is an important method of treatment of cancer. At present, domestic and foreign drugs(Avastin,Endostar) have been listed for tumor blood vessels,but these drugs are expensive and injection, therefore,the drug development of low dosage and oral of anti-angiogenesis is the target of cancer treatment.Endothelial cells are the most important cells involved angiogenesis. Therefore,the inhibition of the growth of endothelial cells can block angiogenesis and inhibit the tumor. In this paper,we used human microvascular endothelial cells (HMEC) as a drug screening model to screen different extraction components of Albizia,look for the active component and low toxicity,and discuss the effective components in vivo toxicology, drug pharmacodynamics effects in vivo and in vitro through the active component of the dry matter yield,ease of process route and the toxicity of endothelial cells as the evaluation index.We used three methods to extract effective components. One was the solution of freeze-dried powder of raw materials,Extracted with petroleum and n-butanol to obtain n-butanol phase. The next one was the solution of freeze-dried powder with water saturated butanol after ethanol solution to obtain n-butanol phase. The last one was the solution of part of freeze-dried powder of the alcohol extraction and extracted with n-butanol to obtain n-butanol phase. These methods were simple, components were high yield of dry matter, good activity and low toxicity.We found a significant inhibition of vascular endothelial cell proliferation through the pharmacodynamic study of the three extracts. And the three extracts inhibited the migration of vascular endothelial cell. The components 23 also inhibited angiogenesis significantly.Through the toxicology study of three extracts, we found the main toxic manifestations were:extended blood clotting time; reduced frequency of spontaneous activity in mice;the heart,liver,lung,kidney and brain's damages were significantly; decrease of SOD activity and increase of MDA content in the brain,lung,kidney,heart and liver tissue; increased serum the concentration of BUN, GOT and GPT. Toxicity of three effective components by a further comparison, components 23 was the least toxic,and considered as the ideal component, so to further explore the in vivo efficacy.The vivo pharmacodynamic study of components 23 demonstrated that after giving components 23,could improve the appetite and quality of life in mice, inhibit tumor growth, nuclear pyknosis,necrosis and infiltration of inflammatory,and have dose-related.This study established the extraction processes of component extraction of Albizia through the extraction rate,biological activity and toxicity of the extraction, got the extracts with the effect of inhibiting the endothelial cells. This extracts could declare the fifth new drug of traditional Chinese medicine as an effective part of Albizia julibrissin, and further developed into a new anti-tumor angiogenesis.