Boosting The Liver-targeting Effect Of Curcumin And DiR-PLGA-NPs Via The Meridian Drug Bupleurum

Objective:By combining the theory of guiding meridians with the study of targeting drug delivery system?TDDS?,the liver-targeting effect of curcumin and a new drug delivery system nanoparticles could be promoted by bupleurum,providing a new idea and method for liver targeted TDDSMethods:1.Taking the content of saikosaponin a and d as the evaluation index,the effects of material liquid ratio,extraction time and extraction times on the content of saikosaponin a and d in the water extraction process were investigated by single factor test,and the water extraction process of bupleurum was optimized by response surface method.2.To establish an HPLC method for the analysis of curcumin in rat plasma samples,we determined the curcumin?500 mg/kg?in blood at different times after intragastric administration of curcumin?500 mg/kg?alone and combined administration of bupleurum in low,medium and high doses?0.50 g/kg,1.00 g/kg,2.00 g/kg?.According to the results,we drawed the concentration-time curve and calculated the pharmacokinetic parameters.3.Establish an HPLC analysis method for curcumin in rat liver,heart,spleen,lung and kidney tissue samples,measure the curcumin concentration in liver,heart,spleen,lung and kidney tissue at different time points after rats are fed with curcumin?500 mg/kg?and combined with low,medium and high doses?0.50 g/kg,1.00 g/kg,2.00 g/kg?of Bupleurum,evaluate the tissue distribution characteristics,and evaluate curcumin after combined administration with peak concentration ratio?Ce?,total targeting coefficient?Te?,drug distribution efficiency?Rte?and relative uptake rate?Re?4.PLGA nanoparticles with dir were prepared by self emulsifying solvent diffusion method.Based on the single factor test,the formulation was optimized by orthogonal test,and the quality of the nanoparticles was evaluated.The mice were given dir nanoparticles by injection and gavage.At the same time,the bupleurum extract was given by gavage.At different times,the small animals were used in vivo fluorescence imaging technology The abdomen of mice was photographed and the image information was collected to investigate the effect of Bupleurum chinense on the liver targeting of nanoparticles.Results:1.The best water extraction process of Bupleurum chinense was as follows:the ratio of material to liquid was 1:10?g/ml?,the extraction time was 30 minutes,and the extraction times were 3 times.The optimized extraction technology of Bupleurum chinense is stable and feasible.2.The pharmacokinetic process of curcumin by intragastric administration in rats conforms to a two-compartment model,with double peaks in the drug-time curve.Compared with curcumin alone group,curcumin+low and medium dose Bupleurum group is close to its peak concentration with C_maxax of 0.27 0.04,0.23 0.02 and 0.250.03?g/ml respectively.The half-lives t_1/2/2 were 20.84 4.43,18.62 2.66 and 23.79 4.98h,respectively.The half-lives t_1/2/2 of curcumin combined with medium dose Bupleurum group were prolonged.The average residence time MRT_0-12-12 was not significantly different,being 5.69 0.09,5.74 0.05 and 5.75 0.11 h respectively.The above data of curcumin+high dose Bupleurum group decreased3.After intragastric administration of curcumin,the rats were distributed in liver,heart,spleen,lung and kidney,and more in liver.Compared with other tissues,the distribution of curcumin in liver at each time point was higher than that of other organs.The curcumin content was the highest at 15 minutes,reaching 330.04±3.74ng/g.When curcumin is combined with Bupleurum,it can affect the distribution of curcumin in rats.Different doses of Bupleurum have different effects on the distribution of curcumin in vivo.After the combination of curcumin and low-dose Bupleurum,the maximum content of the drug in the liver was increased by about 2times,and the drug concentration in the heart,spleen,lung,and kidney were increased.,With significant differences.After curcumin combined with middle-dose Bupleurum,the liver had the highest drug content at 5 minutes,and the drug concentrations in the heart,liver,spleen,lung,and kidney all increased.Statistical analysis of the two groups of data showed that the distribution of curcumin in each tissue was significantly different;the statistical analysis of the Bupleurum middle-dose group and the low-dose group also showed significant differences in each organ.The combination of high-dose Bupleurum and curcumin reduced the distribution of drugs in all organs except the spleen.Taking peak concentration ratio,total targeting coefficient and drug distribution as evaluation indexes,curcumin's liver targeting effect is best in Bupleurum low dose group,and spleen targeting effect is also best in Bupleurum low dose group.4.The optimal prescription for the preparation of the selected DiR-PLGA-NPs is:PLGA75/25COOR as carrier material,concentration 0.2%,volume ratio of organic phase to water phase 3:25,PVA concentration 2%,the average particle size of the prepared DiR-PLGA-NPs is?540.38±1.98?nm,Zeta potential?--20.30±1.10?mV,and encapsulation efficiency is?92.90 0.11?%.DiR-PLGA-NPs is difficult to be absorbed in gastrointestinal tract of mice after intragastric administration.It has no liver targeting property and has no significant difference when combined with Bupleurum root.After the tail vein injection of DiR-PLGA-NPs,the fluorescence signal intensity of the tail vein injection of DiR nanoparticles gradually increased and showed signs of weakening after 8 h.Judging from the location of the fluorescence signal emitted by the mouse,the main liver,spleen and lung were enriched.After 8h dissection,it was confirmed that the fluorescence signal was mainly located in liver,spleen and lung,and liver had the strongest fluorescence signal.The combination of Bupleurum chinense and nanoparticles has certain effect on liver targeting of mice,and is dose-related.Low dose Bupleurum chinense synergetic nanoparticles have enhanced liver targeting effect in the early stage of administration,medium dose Bupleurum chinense can prolong the time of liver targeting effect,and has enhanced liver targeting effect in the late stage of administration.High dose Bupleurum chinense synergetic nanoparticles have certain effect in the middle stage of administration.Conclusion:1.The pharmacokinetic process of curcumin and curcumin combined with low,medium and high doses of Bupleurum chinense DC by intragastric administration in rats is in accordance with a two-compartment model.Compared with curcumin group alone,curcumin combined with low and medium dose Bupleurum has no significant difference in pharmacokinetics in vivo and has significant influence on tissue distribution.Bupleurum has the effect of introducing curcumin into liver meridian in rats.The pharmacokinetics and tissue distribution of curcumin in vivo decreased after combined with high dose Bupleurum chinense.It is presumed that the high dose of Bupleurum chinense is too high in concentration and viscosity,and the absorption of gastrointestinal tract of rats is affected by intragastric administration,which leads to the reduction of pharmacokinetics and tissue distribution of curcumin in vivo.2.DiR-PLGA-NPs can be successfully prepared by self-emulsifying solvent diffusion method,and the encapsulation efficiency is high,and the particle size and appearance also meet the requirements.The combination of Bupleurum chinense and nanoparticles has certain effect on liver targeting of mice,and is dose-related.Low dose Bupleurum chinense synergetic nanoparticles have enhanced liver targeting effect in the early stage of administration,medium dose Bupleurum chinense can prolong the time of liver targeting effect,and has enhanced liver targeting effect in the late stage of administration.High dose Bupleurum chinense synergetic nanoparticles have certain effect in the middle stage of administration.