目的 鉴于胆固醇潜在的健康危害，探索利用甘草酸替代胆固醇，制备用以替代胆固醇脂质纳米粒（cholesterol lipid nanoparticles，CLN）的甘草酸脂质纳米粒（glycyrrhizic acid lipid nanoparticles，GLN），通过包载抗肿瘤药物雷公藤甲素（triptolide，Tr）制备载雷公藤甲素的甘草酸脂质纳米粒（GLN loaded with triptolide，Tr@GLN），探讨甘草酸替代胆固醇制备抗肿瘤纳米载体的适宜性。方法 采用乙醇注入法分别制备Tr@GLN和载雷公藤甲素的胆固醇脂质纳米粒（CLN loaded with triptolide，Tr@CLN），分别测定两者粒径、多分散指数（polydispersity index，PDI）、ζ电位、药物包封率和载药量；透射电子显微镜（transmission electron microscope，TEM）拍摄其形态；共聚焦显微镜拍摄人肝癌HepG2细胞对两者摄取情况；建立皮下荷瘤肝癌小鼠模型，对比研究Tr@GLN与Tr@CLN的体内抗肿瘤效果。结果 与Tr@CLN相比，Tr@GLN在粒径、PDI、ζ电位、包封率和载药量等理化性质均无显著性差异。Tr@GLN和Tr@CLN的平均粒径分别为（115.59±1.23）、（97.28±0.95）nm；ζ电位分别为（−19.63±3.14）、（−7.77±0.12）mV；Tr包封率分别为（89.70±0.39）%、（87.39±0.37）%；Tr载药量分别为（2.25±0.01）%、（2.31±0.01）%；甘草酸包封率为（87.46±0.65）%；甘草酸载药量为（13.41±0.09）%。TEM观察到，相比Tr@CLN，Tr@GLN呈更加均匀圆整的球状。GLN增加了HepG2细胞对药物的摄取。给药12 d后，Tr@GLN对荷瘤小鼠肿瘤体积抑制率达到78.9%，显著高于Tr@CLN组抑制率（42.4%）和Tr组抑制率（18.3%）（P＜0.05），Tr@GLN治疗后肿瘤中重组Ki-67蛋白（recombinant Ki-67 protein，Ki-67）表达减少，血管内皮生长因子（vascular endothelial growth factor，VEGF）表达减少，并将肿瘤相关的巨噬细胞从肿瘤M2表型重新诱导为M1表型。结论 制备的Tr@GLN与Tr@CLN具有相似理化性质，但GLN包载更有利于增加肿瘤细胞的摄取，Tr@GLN表现出更强的抗肿瘤作用，其抗肿瘤作用可能与抑制肿瘤细胞分化、减少肿瘤新血管生成、促进肿瘤相关巨噬细胞的极化调节相关，说明所构建的GLN适宜于作为纳米载体，为抗肿瘤药物的高效传递提供新思路。

Objective In view of the potential health hazards of cholesterol, glycyrrhizic acid was explored to replace cholesterol to prepare glycyrrhizic acid lipid nanoparticles (GLN) for replacing cholesterol lipid nanoparticles (CLN). GLN loaded with triptolide (Tr@GLN) were prepared by encapsulating the anti-tumor drug triptolide (Tr), to explore the suitability of glycyrrhizic acid replacing cholesterol in the preparation of anti-tumor nanocarriers. Methods Tr@GLN and CLN loaded with triptolide (Tr@CLN) were prepared by ethanol injection method, and the particle size, PDI, ζ potential, drug entrapment efficiency and drug loading efficiency of Tr@GLN and Tr@CLN were measured respectively. The morphology of Tr@GLN and Tr@CLN was photographed by transmission electron microscope (TEM). The cell uptake of the both in HepG2 hepatocellular carcinoma cells was measured by confocal microscopy. The subcutaneous tumor-bearing liver cancer mouse model was established, and the in vivo antitumor effects of Tr@GLN and Tr@CLN were compared. Results Compared with Tr@CLN, the physicochemical properties of Tr@GLN, such as particle size, PDI, ζ potential, entrapment efficiency and drug loading efficiency, were not significantly different. The particle sizes of Tr@GLN and Tr@CLN were (115.59 ±1.23), (97.28 ±0.95) nm; ζ Potential were (−19.63 ±3.14), (−7.77 ±0.12) mV; The entrapment efficiency of Tr were (89.70 ±0.39)%, (87.39 ±0.37%)%; The drug loading efficiency of Tr were (2.25 ±0.01)%, (2.31 ±0.01)%; The entrapment efficiency of GL was (87.46 ±0.65)%; The drug loading efficiency of GL was (13.41 ±0.09)%. Compared with Tr@CLN, Tr@GLN showed a more uniform spherical shape by TEM. GLN increased drug uptake by HepG2 hepatoma cells. After 12 d of administration, the tumor volume inhibition rate of Tr@GLN on tumor-bearing mice reached 78.9%, which was significantly higher than that of Tr@CLN group (42.4%) and Tr group (18.3%) (P < 0.05). The expression of recombinant Ki-67 protein (Ki-67) and vascular endothelial growth factor (VEGF) in tumors decreased after Tr@GLN treatment, and tumor-associated macrophages were reinduced from the tumor M2 phenotype to the M1 phenotype. Conclusion The Tr@GLN prepared in this study has similar physicochemical properties to Tr@CLN, and the encapsulation of GLN is more beneficial to increase the uptake of tumor cells. Tr@GLN showed stronger anti-tumor effect, and its anti-tumor effect may be related to inhibiting tumor cell differentiation, reducing tumor neo-vascularization, and promoting the polarization adjustment of tumor-associated macrophages, indicating that the constructed GLN is suitable as a nanocarrier, and provides a new idea for the efficient delivery of anti-tumor drugs.

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国家自然科学基金面上项目（81973662）；国家中医药管理局中医药创新团队及人才支持计划项目（ZYYCXTD-D-202209）