Study On Antitumor Pharmacodynamics And Targeting Of Genistein-loaded MePEG-PLGA Namo-micelle In Vivo And In Vitro

[Objective]Genistein has a wide range of anti-tumor effects,low toxicity and low side effects,whereas genistein is almost insoluble in water.In this experiment,genistein was prepared as a GEN-loaded MePEG-PLGA nanomicelles,which improved the bioavailability of the drug and increased its targeting.The distribution of the drug was observed through the in vivo distribution of the mice;The effects of GEN micelles on the cytotoxicity,apoptosis and cell cycle of hepatocarcinoma SMMC-7721 cells was investigated;The GEN micelles were used to investigate the tumor inhibition of SMMC-7721 tumor-bearing nude mice;The in vivo imaging technique of small animals was used to observe the targeting characteristics of micelles,and the tissue distribution of GEN micelles in nude mice bearing hepatocellular carcinoma was evaluated.This study provides a certain experimental basis for the development and application of new anti-tumor traditional Chinese medicine formulations in clinical practice.[Method]GEN-loaded MePEG-PLGA nanomicelles were prepared by the modified spontaneous emulsification solvent diffusion method.The distribution of GEN and GEN micelles in mice was investigated by mouse in vivo experiments.MTT assay was used to investigate the toxicity of GEN,GEN micelles,and blank micelles on hepatoma SMMC-7721 cells.The effects of GEN and GEN micelles on the apoptosis and morphology of SMMC-7721 cells were investigated by Annexin V-FITC/PI double staining and Hoechst 33342 staining.The effects of GEN micelles on the cell cycle of SMMC-7721 cells were investigated by PI staining.The in vivo antitumor effect of genistein was investigated in nude mice bearing hepatocellular carcinoma SMMC-7721 tumor in vivo.The distribution of GEN micelles was qualitatively investigated by the in vivo imaging technique of small animals and distributed in mice.Through the in vivo distribution experiment of mice,the distribution of GEN micelles in nude mice was quantitatively examined to observe its targeting.[Results]Through the in vivo distribution of mice,it is known that GEN micelles significantly increase the retention time of drugs in plasma compared to GEN-Emulsions.The RUE and Ce values of plasma and lungs are all greater than 1.The degree of drug accumulation in the heart,liver,spleen,and kidney decreased to a lesser extent,but there was no significant change in the brain,and the drug concentration in the liver and blood was higher;At the same time(24h,48h,72h)and the same concentration(1.25,2.5,5,10,20,30,40,and 50μg/ml),the inhibitory rate of GEN micelles in SMMC-7721 cells were higher than GEN and the highest inhibition rates were 83.26%and 78.25%,respectively;When the GEN and GEN micelles with the concentration of 5μg/ml,10μg/ml,and 20μg/ml were applied to SMMC-7721 cells for 48 h,the results of flow cytometry showed that the GEN micelles group could increase the ability of GEN to induce apoptosis of SMMC-7721 cells and presented a concentration-dependent manner.Apoptosis was observed by Hoechst33342 staining.After staining,the cells became bright and the nucleus was pyknosis.The results were consistent with flow cytometry;When the concentration of 5μg/ml,10μg/ml,20μg/ml GEN and GEN micelles groups acted on SMMC-7721 cells for 48h,the GEN micelles could significantly enhance the the ability of arrest cell in G2/M phase for GEN,and showing a concentration-dependent manner;In vivo anti-solid tumor experimental results showed that the blank micelles had almost no effect on the inhibition of tumor growth,and the other experimental groups had inhibitory effects on tumor growth.The same concentration of GEN micelles group had significantly better antitumor effect than GEN-Emulsion,and in a concentration-dependent manner,the highest tumor inhibition rate was 55.41%;The in vivo imaging of small animals showed that the GEN micelles can effectively target the drug to tumor.The in vivo distribution of tumor-bearing nude mice further demonstrated that GEN micelles can significantly increase the accumulation of drugs in tumor and enhance the concentration in the blood,while reduce the toxicity to the heart,liver,spleen,and kidneys.[Conclusion]The GEN-loaded MePEG-PLGA nanomicelles can improve the distribution of drugs in mice,greatly increase the residence time of drugs in the blood,significantly enhance the anti-tumor effect of drugs in vivo and in vitro,and have certain passive targets.This study provides methods and support for in vivo and in vitro antitumor studies of poorly soluble drugs.