双响应性透明质酸碳量子点-明胶纳米递药系统的构建及抗肿瘤效果评价

Construction and Anti-tumor Effect Evaluation of a Dual-Responsive Hyaluronic Acid Carbon Quantum Dot-Gelatin Nano-Drug Delivery System

目的通过构建pH和基质金属蛋白酶(matrix metalloproteinase,MMP)双响应性粒径可变纳米递药系统,协同提高化疗药物在肿瘤组织的高效滞留和高效穿透,增强肿瘤治疗效果。方法构建了透明质酸(hyaluronic acid,HA)碳量子点(carbon quantum dots,CD)偶联明胶纳米粒(gelatin nanoparticle,GNP),通过pH敏感的亚胺连接化疗药物阿霉素(doxorubicin,DOX),得到GNP@HA-CD-DOX纳米粒并进行表征,考察粒径变化能力、释药行为、血液相容性、细胞摄取和肿瘤球深层穿透能力、体内肿瘤分布以及治疗效果。结果GNP@HA-CD-DOX纳米粒粒径为(162.93±2.55)nm,在MMP处理下可降解释放出粒径约40 nm的HA-CD-DOX。该纳米粒DOX载药量为(4.94±0.22)%,DOX可以在肿瘤微环境和溶酶体中响应低pH释放。GNP@HA-CD-DOX无明显溶血现象;与MMP-2共孵育后粒径减小,能够明显提高细胞摄取和肿瘤球中的深层穿透。GNP@HA-CD-DOX在荷瘤小鼠模型上表现出优于小粒径HA-CD-DOX的肿瘤分布和抗肿瘤能力,且安全性较好。结论该pH和MMP酶双响应粒径可变的纳米递药系统协同提高药物在肿瘤的滞留和深层穿透,提高了抗肿瘤效果,为肿瘤治疗提供了新的思路。

Objective To construct a pH and matrix metalloproteinase(MMP)dual-responsive nano drug delivery system with adjustable particle size so as to synergistically enhance the retention and penetration of chemotherapeutic drugs in tumor tissues and improve tumor treatment effect.Methods Hyaluronic acid(HA)carbon quantum dots(CD)coupled with gelatin nanoparticle(GNP)were constructed,and were connected with doxorubicin(DOX),a chemotherapeutic drug,through pH-sensitive imine to produce GNP@HA-CD-DOX nanoparticles.The changes of particle size,drug release behavior,hemocompatibility,cell uptake and deep penetration of tumor spheroids,in vivo tumor targeting and therapeutic effect were analyzed.Results GNP@HA-CD-DOX nanoparticles had a particle size of(162.93±2.55)nm,which could be degraded to release HA-CD-DOX with a particle size of about 40 nm under the treatment of MMP.The drug loading of DOX was(4.94±0.22)%.DOX was released in the tumor microenvironment and lysosomes in response to the low pH.No obvious hemolysis was observed in GNP@HA-CD-DOX.GNP@HA-CD-DOX showed a reduction in particle size after co-incubation with MMP-2.The MMP-sensitive GNP@HA-CD-DOX had significantly improved cell uptake and better deep penetration in tumor spheres.GNP@HA-CD-DOX displayed better distribution in tumor and anti-tumor ability in tumor-bearing mice compared with the small particle size HA-CD-DOX group.In addition,it has better safety.Conclusion The pH and MMP dual-sensitive nano-tech drug delivery system with adjustable particle sizes synergistically enhances the retention and deep penetration of drugs in tumors as well as the anti-tumor effect,suggesting new approaches to tumor treatment.