Study On Antineoplastic Activity And Mechanism Of Alkaloids From Artemisia Annua

Objective:By detecting the antitumor activity and their target proteins of alkaloids isolated from Lam.Incarvillea sinensis.It was proved that the alkaloids could be used as natural anti-tumor drugs.Methods:（1）The total extract was obtained by ethanol reflux extraction and then the total alkaloid fraction was obtained by acid-base extraction method.（2）The alkaloid monomers were isolated by gel column（Sephadex LH-20）and liquid chromatography.（3）The activity of alkaloid monomers on gastric cancer cells BGC-823 were detected by MTT.（4）Flow cytometry was used to detect the effects of alkaloid monomer on apoptosis and cycle of tumor cells.（7）The effect of alkaloid monomer on cytoskeleton was observed by fluorescence confocal microscope.（8）The level of active Rac1 was detected by G-LISA^TM assay.Results:（1）60 monomers were obtained by subdivision of chloroform site.（2）The MTT assay showed that the monomers with good tumor inhibitory activity on gastric cancer cell line BGC-823 were JH-B22,JH-26,JH-27 and JH-44.The inhibitory activity of JH-B22,JH-26,JH-27 was time-and dose-dependent.Its IC50 were13.48μmol/L,9.153μmol/L and 8.601μmol/L,respectively.The inhibitory rate of JH-44 on BGC-823 cells was 40%at the concentration of 10,15,20μmol/L.（3）Four monomers were found to increase the late apoptosis rate of gastric cancer cell line BGC-823 by flow cytometry analysis（4）In the study of the effect of active components on the cell cycle of BGC-823,it was found that the other three monomers,except JH-44,could increase the percentage of G0/G1 phase cells.（5）By fluorescence confocal microscopy,it was found that compound JH-B22,JH-27significantly reduced the formation of Lamellar pseudopodia in tumor cells,while JH-44,JH-26 had no obvious effect on cytoskeleton.（6）The inhibitory rate of JH-B22,JH-27 on active Rac1 was 66.5%and 71.4%respectively at the concentration of 50μmol/L.Conclusion:（1）Some of the isolated alkaloids of Lam.Incarvillea sinensis have inhibitory activity on gastric cancer cell line BGC-823,among which the monomer with the best inhibitory activity has IC50<10μmol/L.（2）The alkaloid monomer of Artemisia annua not only inhibited the BGC-823 of gastric cancer cells,but also affected the apoptosis and cell cycle of tumor cells.（3）Some alkaloids could obviously change the reorganization of cytoskeleton of BGC-823 cells and decrease the formation of Lamellar pseudopodia.（4）Alkaloids have the activity of inhibiting Rac1.