半乳糖基壳聚糖/5-氟尿嘧啶纳米粒抑制小鼠肝癌的实验研究

Experimental study of the inhibition of galactosylated chitosan/5-fluorouracil nanoparticles on liver cancer in mouse

目的制备半乳糖基壳聚糖(GC)/5-氟尿嘧啶(5-Fu)纳米粒,观察其缓释特性及对小鼠肝癌的抑制作用。方法通过GC和5-Fu合成纳米粒,通过体外释放实验观察其缓释作用和体外实验观察GC/5-Fu纳米粒对肿瘤细胞抑制率和半数抑制率浓度值(IC50)。结果 GC/5-Fu纳米粒成功合成,呈规则的球形,表面光滑,大小均匀,纳米粒间无粘连。0～12 h出现突然快速释放,其累计释放率为32.4%;1～8 d出现平稳的缓慢释放,其累计释放率为93.50%;8～10 d呈平台期缓慢释放,10 d时累计释放率达95.70%。5-Fu和GC/5-Fu纳米粒对人结肠癌细胞株(SW480)和人肝癌细胞株(SMMC-7721)杀伤具有药物浓度越大,杀伤作用也就越强的量效依赖关系。在24 h、48 h和72 h,肿瘤抑制率从GC/5-Fu-SMMC-7721,5-Fu-SW480,5-Fu-SMMC-7721和GC/5-Fu-SW480依次降低。5-Fu的时间依赖性杀伤效应主要在1～6 d,在此期间的各个时相点,其IC50从GC/5-Fu-SMMC-7721,5-Fu-SW480,5-Fu-SMMC-7721和GC/5-Fu-SW480依次升高,但7 d后,5-Fu-SW480和5-Fu-SMMC-7721的时间依赖性杀伤效应进入一个平台期;而GC/5-Fu-SMMC-7721和GC/5-Fu-SW480的时间依赖性杀伤效应则从1～10 d呈持续增加趋势,并且6 d后,GC/5-Fu-SW480的IC50值小于5-Fu-SW480和5-Fu-SMMC-7721。结论 GC/5-Fu纳米粒具有缓释作用,体外对肿瘤细胞的杀伤作用具有量效依赖性和时间依赖性,对小鼠原位肝癌具有明显抑制作用,较5-Fu明显增强。

Objective It is to prepare the galactosylated chitosan （GC）/5 - fluorouracil （5 - Fu） nanoparticles, to observe its release characteristics and its effect on the inhibition of liver cancer in mice. Methods GC/5 - Fu nanoparticles were synthesized by GC and 5 - Fu, the sustained release in vitro were performed, the inhibition rate of tumor cells with the GC/5 - Fu nanoparticles and half inhibition rate of concentration value （1Cso） were observed in vitro. Results 5 - Fu/GC nanoparticles were successfully synthesized, electron microscopy showed that the particles were regular spherical shapes, with a smooth surface, a uniform size, and no adhesion between nanoparticles. A rapid release was observed from time 0 h to 12 h, with a cumulative release percentage of 32.4% ; a smooth slow-release occurred between day 1 and day 8, with a cumulative release percentage of 93.50%. During days 8 to 10, the release reached a plateau, with a cumulative release percentage of 95.70% at day 10. 5 - Fu and GC/5 - Fu inhibited the growth of SW480 and SMMC - 7721 ceils in a dose - dependent manner. At the 24, 48 and 72 h time points, the tumor cell inhibitory rate showed a decreased tendency from GC/5 - Fu - SMMC - 7721 to 5 - Fu - SW480 to 5 - Fu - SMMC - 7721 to GC/5 - Fu - SW480. 5 - Fu the time-dependent killing effect in the l to 6 d, the points during the IC50 from GC/5 - Fu - SMMC -7721 5 - Fu - of SW480, 5 - Fu - in SMMC - the 7721 GC/5 - Fu - SW480 turn increased, 5 - Fu - SW480 and 5 - Fu - of SMMC -7721 time-dependent killing effects into a plateau after 7 d; and GC/5 - Fu - SMMC the -7721 and GC/5 - Fu - SW480 of time dependent killing effect from the 1 for 10 days showed in- creasing trend, and 6 d after GC/5 - Fu - SW480 the IC50 value of less than 5 - Fu - SW480 5 - Fu - SMMC -7721. Conclusion GC/5 -Fu nanoparticles has a sustained release effect, and its hepatic cell -targeting cytotoxicity is dose and time dependent, it has a obviously inhibition on hepatocellular carcinoma in mouse, which was more obviously than that of 5 -Fu.