Preliminary Study On The Anti-breast Cancer Activity Of Sodium Bunkanka Saponins E And Its Toxicity

Objective:Bunkanka saponin E?hereinafter referred to as“BE”?is a kind of barringenol-like triterpenoids saponins with remarkable biological activity,which is abundant in the carapax and carpopodium of Xanthoceras sorbifolia Bunge.It was found that it has strong anti-tumor activity.In this study,a structural modification was carried out to solve the problem of poor water solubility of BE and to ensure that its anti-tumor activity was not affected.The pharmacodynamics of BE-Na against breast cancer were verified in vivo and in vitro.In terms of drug safety,the acute toxicity experiment and hemolysis of BE were studied.The purpose of these studies are to provide reference for the study on the drug use of BE.Method:Sodium bunkanka saponins E?hereinafter referred to as“BE-Na”?was obtained by chemical reaction of BE with equal mole NaOH.The IC₅₀ of BE and BE-Na on 4T1were determined.The antitumor activity of BE-Na was verified by comparison.4T1 and Balb/c mice were used to construct a 4T1 tumor-bearing mouse model.To evaluate the effect of inhibitory proliferation activity of BE-Na by comparing the weight and volume of tumors in 4T1 tumor-bearing mice.They were randomly assigned to the model group?normal saline?,the positive drug group(adriamycin hydrochloride group:5mg·kg^-1),the low-dose BE-Na group(0.5mg·kg^-1)and the high-dose BE-Na group(1.0mg·kg^-1).Each group was given the drug every 2 days for 5 times continuously.24 hours after the last administration,the mice in each group were sacrificed by cervical dislocation,and the subcutaneous tumor tissue was taken,the tumor mass was weighed,and the tumor inhibition rate and tumor volume were calculated to evaluate the tumor inhibitory activity.MCF-7 was introduced as the subject of cell experiment,cytotoxicity was determined by CCK-8,and the effect of different concentrations of BE-Na on the expression of MCF-7protein was detected by Western blot.Female mice were selected to conduct the up and down procedure and Bliss method to determine LD₅₀.1 mg·kg^-1 as the starting dose for the up and down procedure and the adjacent dose ratio as 1:0.7.The drug administration was i.v.and the test was conducted in accordance with the technical guidelines for acute toxicity test of chemical drugs.Bliss method were randomly divided into seven groups,including six dose groups(4.08,5.83,8.33,11.90,17.00,24.28 mg·kg^-1)and the control group.After intravenous injection,every group were continuous observation for 14 days,record the cumulative survival,food consumptions,weight,using the Bliss method to calculate LD₅₀.After observation,pathological of organs and the expression of GOT,GPT and Cr would be tested.Female rabbits were used to the hemolysis experiment.All procedures were under the guidance of the rule for“hemolysis and coagulation test”in Chinese Pharmacopoeia,2015 edition.Result:The structural modification site of saponins was active hydrogen on the carboxyl group of glucuronic acid and it doesn't change its functional groups very much.It was found that there was no significant difference in their activities by comparing the IC₅₀ of BE and BE-Na.The experimental results of BE-Na on 4T1 mouse model showed that in terms of both weight and volume,the drug delivery group and the positive drug group were significantly lower than the control group.BE-Na has obvious growth inhibition activity on tumors of 4T1 tumor-bearing mice.In the MCF-7 cell assay,the IC₅₀ was5.33?M.The expression level of BAD was decreased?P<0.05?,while the expression level of caspase-3 was increased?P<0.05?.Meanwhile,the ratio of Bax to bcl-2 was on the rise.The LD₅₀ of BE-Na was 8.35 mg·kg^-1.The results of Elisa and H&E staining test were showed the toxicity of liver and kidney respectively.BE-Na has shown strong hemolytic activity at 0.63?g·ml^-1 and its safe dosage should be less than 0.31?g·ml^-1.Conclusion:The modification of BE had no obvious effect on inhibiting the activity of tumor cells while solving the problem of poor water solubility of BE.Therefore,we preliminarily believe that BE-Na can replace BE in the study of its anti-tumor activity and its mechanism.Pharmacodynamics of BE-Na in vitro and in vivo show that it had significant anti-breast cancer activity.BE-Na has low safety dosage threshold,strong hemolytic activity and toxicity of liver and kidney.It is speculated that the hemolysis of BE might be one of factors leading the toxicity,and this property for BE should be adjusted for its developing as a new medicine.The above provide references for the subsequent studies on BE as a drug.