OX26耦联载内吗啡肽的超支化聚甘油-聚乳酸-聚乙醇酸纳米粒细胞毒性及血液相容性的实验研究

Study on the cytotoxicity against brain microvessel endothelial cells and blood compatibility in rat of OX26 conjugated endomorphin loaded HBPG-PLGA nanoparticles

目的考察OX26耦联载内吗啡肽的超支化聚甘油-聚乳酸-聚乙醇酸（OX26-EM—HBPG—PLGA）纳米粒细胞毒性及血液相容性，为安全用于动物实验提供依据。方法将纳米粒分为B组（HBPG—PLGA纳米粒）、EP组（EM—HBPG—PLGA纳米粒）、OEP组（OX26-EM．HBPG—PLGA纳米粒）组，分别采用噻唑蓝比色法（MTT法）考察各组纳米粒对大鼠脑毛细血管内皮细胞（BMECs）的细胞毒性、兔血溶血率；通过正常大鼠静脉注射各组纳米粒考察其对血常规和凝血系统的影响。结果①不同类型纳米粒对BMECs的细胞毒性呈浓度依赖性；3组纳米粒对细胞都有一定毒性作用，在质量浓度为30～600μg／ml范围内，其细胞抑制情况较低且稳定，质量浓度为2700μg／ml时，细胞活力明显下降（P〈0．01）。②无论纳米粒浓度高低，兔血红细胞溶血率均低于5％，各组差异无统计学意义（P〉0．05），符合医用实验材料的溶血要求。③各组纳米粒对血常规均无影响（P〉0．05）。④3组纳米粒低剂量组与对照组比较，各凝血指标差异无统计学意义（P〉0．05）。与对照组相比，高剂量组凝血酶原时间（胛）、活化部分凝血活酶时间（APTT）明显延长，纤维蛋白原（Fbg）含量明显下降，差异有统计学意义（P〈0．05），而且与同组低剂量组比较，高剂量组PT、APTT明显延长，Fbg含量明显下降，差异有统计学意义（P〈0．05或P〈0．01）。结论较低浓度和合适剂量的OX26-EM—HBPG—PLGA纳米粒对BMECs毒性低微，溶血率低，对大鼠血常规凝血系统没有影响，具有良好的生物安全性。

Objective To study the cytotoxicity against brain microvessel endothelial cells and blood compatibility in rats of OX26 conjugated endomorphiu （EM） loaded hyperbranched polyglycerols-poly（lactie-co-glycolic aeid）（HBPG-PLGA） nauoparticles. Methods Prepared nauopartieles were divided into group B （HBPG-PLGA nanopartieles）, group EP （EM-HBPG-PLGA nanopartieles） and group OEP （OX26-EM-HBPG-PLGA nauoparticles）. The cytotoxicity against brain microvessel endothelial cells （BMECs） of nanoparticles of different groups were measured by MTT test, haemolysis test, normal haemotological parameter and several primary items of coagulation system were tested after uauoparticles of different groups and different dosages injection on rats. Results ①All the three groups of uanoparticles induced decreased cell viability in a dose dependent manner in MTT test, whereas all groups of nanoparticles showed low cytotoxicity against the BMECs during 30 to 600 μg/ml. ②There was no significant difference in haemolysis ratio （P〉0.05） and normal haemotologieal parameter （P〉0.05）.③There was no significant difference between the low dosage of all the three groups of nanoparticles and the control group on the function of coagulation system in rats （P〉0.05）. ④Compared with C group, high dose groups demonstrated longer prothrombin time （PT）, activeated partial thromboplasting time （APTT and lower fibrinogen （Fbg） （P〈0.05）. At the same time, compared with the low dose subgroups, PT and APTT were prolonged, Fbg significantly decreased in the high dose subgroups （P〈0.05 or P〈0.01）. Conclusion OX26 coupled with EM- HBPG-PLGA nanoparticles showed low cytotoxicity against BMECs and had no significant effect on the coagulation system in rats with low concentration and low dosage.