Research About Constituent From Peucedanum Praeruptorum Induces Cancer Cell Apotosis Through RXR? Receptor

In rencent years,malignat tumor has become the second deadly diseases due to the rising incidence rates.Searching for the effective antitumor drugs have become the top priority.Retinoic acid receptor X(RXRa)is an ideal drug target for the treatment of cancer.Previous research found that coumarins could induce cancer cell apoptosis via RXRa signaling pathway.Owing to the limited types of obtained coumarins,structure activity relationship and mechanism of action are still unclear.Peucedanum praeruptorum is a rich sources of coumarins,meanwhile,some fractions of P.praeruptorum could inhibit the transcriptional activity of RXRa.Therefore,P.praeruptorum was chosen as the research object of our study.The chemical constisutes and RXRa transcriptional inhibitory activities of coumarins in the active fractions of P.praeruptorum will be studied.Besides,the structure activity relationship and mechanism of action will try to discuss.In our study,various chromotograhic techniques(silica gel column chromatography,macroporous gel column chromatography,ODS column chromatography,sephadex LH-20 chromatography,thin layer chromatography(TLC),recrystallization,preparative HPLC,etc)were used to investigate the the 80%ethanol extract of P.praeruptorum.38 compounds were isolated and their structures and were identified on the basis of the datas from NMR,MS spectra,physical properties and chemical properties.Among the 38 compounds,37 of them are coumarins.Compound 24 was isolated as a new compound;compound 3,35 were isolated from the plants of Peucedanum genus for the first time;compound 9,13,14,30,33,36 were separated from P.praeruptorum for the first time.The mass fragmention pathway and NMR characteristic of the isolated coumarins would be discussed.The methods of nuclear receptor RXRa dual luciferase report gene assay,biacore and western bloting were used to investigate the activities of the isolated compounds.The results suggested that coumpounds 6,8,20,29 showed obvious RXRa transcriptional inhibitory activities in a concentration-dependent manner.Besides,compounds 6,8,20,29 could also induce the cutting of PARP protein meaning that coumarins could induce cancaer apoptosis.In addition,the biacore assay showed that compound 6,8,20,29 could bind RXRa-LBD proteins in a fast up and fast down form with Kd=39.48 ?M,Kd=12.73 ?M,respectively.The above results suggested that coumarins may induced cancer cells apoptosis via the regulation of the RXRa relevant signaling pathways.The preliminary structure-activity relationships were discussed.