Kattel Krishna, Mondal Goutam, Lin Feng, Kumar Virender, Mahato Ram I
Department of Pharmaceutical Sciences, University of Nebraska Medical Center , Omaha, Nebraska 68198, United States.
Mol Pharm. 2017 May 1;14(5):1365-1372. doi: 10.1021/acs.molpharmaceut.6b00929. Epub 2016 Nov 7.
Therapeutic efficacy of gemcitabine (GEM) is severely limited due to its rapid metabolism by enzymatic deamination in vivo. We recently determined its therapeutic efficacy before (F-GEM) and after conjugation to poly(ethylene glycol)-block-poly(2-methyl-2-carboxyl-propylene carbonate) (mPEG-b-PCC-g-GEM-g-DC, abbreviated as P-GEM) in subcutaneous and orthotopic pancreatic tumor bearing mice. In this study, pharmacokinetic (PK) parameters and biodistribution profiles of F-GEM and P-GEM were determined after intravenous injection into orthotopic pancreatic tumor bearing NSG mice. To assess the short-term toxicity, the levels of hematological, hepatic, and renal injury markers were measured after 24 h postadministration into these mice. P-GEM was distributed to all the major organs, with higher accumulation in the liver, spleen, and tumor compared to F-GEM. Area under the curve (AUC), elimination half-life (t), and mean residence time (MRT) of P-GEM treated group were significantly higher compared to those of F-GEM treated group: 246,425 ± 1605 vs 83,591 ± 1844 ng/mL × h as AUC, 5.77 ± 2.02 vs 1.99 ± 0.09 h as t, and 4.45 ± 0.15 vs 1.12 ± 0.13 h as MRT. Further, P-GEM exhibited negligible systemic toxicity as evidenced by almost similar alanine aminotransferase (ALT) and aspartate aminotransferase (AST) values for both P-GEM and F-GEM. These results suggest that P-GEM protects GEM from degradation and provides sustained drug release, resulting in enhanced GEM delivery to the tumor by more than 2.5-fold compared to F-GEM. Hence, P-GEM is a promising gemcitabine conjugated polymeric micelle for treating pancreatic cancer.
吉西他滨(GEM)的治疗效果在体内因酶促脱氨作用导致的快速代谢而受到严重限制。我们最近在皮下和原位胰腺癌荷瘤小鼠中测定了其在与聚(乙二醇)-嵌段-聚(2-甲基-2-羧基-碳酸丙烯酯)(mPEG-b-PCC-g-GEM-g-DC,简称为P-GEM)偶联之前(F-GEM)和之后的治疗效果。在本研究中,将F-GEM和P-GEM静脉注射到原位胰腺癌荷瘤NSG小鼠体内后,测定了它们的药代动力学(PK)参数和生物分布情况。为了评估短期毒性,在给这些小鼠给药24小时后测量血液学、肝脏和肾脏损伤标志物的水平。P-GEM分布到所有主要器官,与F-GEM相比,在肝脏、脾脏和肿瘤中的积累更高。P-GEM治疗组的曲线下面积(AUC)、消除半衰期(t)和平均驻留时间(MRT)显著高于F-GEM治疗组:AUC分别为246,425±1605 vs 83,591±1844 ng/mL×h,t分别为5.77±2.02 vs 1.99±0.09 h,MRT分别为4.45±0.15 vs 1.12±0.13 h。此外,P-GEM表现出可忽略不计的全身毒性,P-GEM和F-GEM的丙氨酸转氨酶(ALT)和天冬氨酸转氨酶(AST)值几乎相似证明了这一点。这些结果表明,P-GEM可保护GEM不被降解并提供持续的药物释放,导致与F-GEM相比,GEM向肿瘤的递送增强了2.5倍以上。因此,P-GEM是一种用于治疗胰腺癌的有前景的吉西他滨偶联聚合物胶束。