甘草次酸修饰的人参皂苷Rh2脂质体的制备及其体外评价

Preparation and in vitro Evaluation of Ginsenoside Rh2 Liposomes Surface-modified with Glycyrrhetinic Acid

摘要:

目的: 制备由甘草次酸修饰的人参皂苷Rh₂脂质体,评价其体外理化性质和对人肝癌细胞SMMC-7721的生长抑制作用。方法: 采用薄膜分散法制备普通的人参皂苷Rh₂脂质体(Rh₂-L)和甘草次酸修饰的人参皂苷Rh₂脂质体(GA-Rh₂-L), 利用UPLC测定人参皂苷Rh₂的含量,流动相乙腈-水(28:72),流速0.3 mL·min^-1,检测波长203 nm。考察脂质体的包封率、粒径、体外释放率及Zeta电位,运用噻唑蓝(MTT)法评价人参皂苷Rh₂溶液,Rh₂-L和GA-Rh₂-L对SMMC-7721细胞体外增殖的 抑制作用。结果: 与Rh₂-L相比,GA-Rh₂-L的包封率、粒径、体外释放率及Zeta电位等理化性质均无显著性差异。Rh₂-L和GA-Rh₂-L的包封率分别为(91.67±1.05)%,(95.54±2.23)%,粒径(138.6±45.8),(146.5±48.9) nm,Zeta电位-(12.75± 0.34),-(14.79±0.67) mV,72 h的体外释放率(84.67±7.23)%,(89.03±8.61)%。人参皂苷Rh₂溶液在12 h内释药率达(91.23±5.17)%。细胞用药2 d后,GA-Rh₂-L对SMMC-7721的半抑制率(IC₅₀)分别为人参皂苷Rh₂和Rh₂-L的0.524,0.596倍,并呈浓度和时间以依赖关系。结论: 甘草次酸修饰不会影响人参皂苷Rh₂脂质体得理化性质,还可增加其对细胞的靶向性,增加了细胞毒性,为肝肿瘤的靶向治疗提供了新思路。

Abstract:

Objective: To encapsulate ginsenoside Rh₂ within glycyrrhetinic acid modified liposomes and investigate its physicochemical properties and in vitro inhibitory effect on SMMC-7721 cells. Method: Ginsenoside Rh₂ liposomes(Rh₂-L) and ginsenoside Rh₂ liposomes surface-modified with glycyrrhetinic acid(GA-Rh₂-L) were prepared by film dispersion method,UPLC was employed to determine the content of ginsenoside Rh₂ with mobile phase of acetonitrile-water(28: 72),flow rate of 0.3 mL·min^-1 and detection wavelength at 203 nm.Encapsulation efficiency(EE),particle size,Zeta potential and in vitro release were measured,MTT experiment was adopted to evaluate inhibitory effect of ginsenoside Rh₂ solution,Rh₂-L and GA-Rh₂-L on SMMC-7721 cells. Result: Modification of glycyrrhetinic acid showed no effect on physicochemical properties of Rh₂-L,such as EE,particle size,Zeta potential and in vitro release.EE of Rh₂-L and GA-Rh₂-L were (91.67±1.05)% and (95.54±2.23)%,average particle size of them were (138.6±45.8) nm and (146.5±48.9) nm,Zeta potential of them were -(12.75±0.34) mV and -(14.79±0.67) mV,respectively.In vitro release of ginsenoside Rh₂ from Rh₂-L and GA-Rh₂-L within 72 h were (84.67±7.23)% and (89.03±8.61)%,while ginsenoside Rh₂ solution released (91.23±5.17)% within 12 h.In vitro cytotoxicities(IC₅₀) of GA-Rh₂-L on SMMC-7721 cells was increased by 0.524 fold compared with ginsenoside Rh₂ solution and 0.596 fold compared with Rh₂-L.Ginsenoside Rh₂ solution,Rh₂-L and GA-Rh₂-L all inhibited proliferation of SMMC-7721 cells in dose-and-time-dependent manners. Conclusion: Glycyrrhetinic acid modification can not affect physicochemical properties of Rh₂-L,and it can increase targeting efficiency of liposomes on hepatocellular carcinoma,thus resulting in higher cytotoxicities in comparison with Rh₂-L.This study provides new ideas for targeted-therapy to hepatocellular carcinoma.