冬凌草甲素固态类脂纳米粒在小鼠体内的组织分布及兔体内的药代动力学

目的考察冬凌草甲素固态类脂纳米粒在动物体内的组织分布及药代动力学特性。方法建立生物样品中冬凌草甲素的HPLC测定法，比较冬凌草甲素普通注射液和固态类脂纳米粒注射液的体内分布特点与药代动力学参数。结果冬凌草甲素固态类脂纳米粒在肝、脾、肺、心及肾中的相对摄取率分别为4.25%，3.44%，1.19%，0.52%和0.60%。静脉注射后的药-时曲线表明体内过程符合三室模型，其各相半衰期分别为T_1/2π=0.087 h，T_1/2α=1.65 h，T_1/2β=32.36 h，中心分布容积V_C=0.66 mL·kg^-1。结论冬凌草甲素固态类脂纳米粒能够增强药物的肝脾靶向性，提高药物生物利用度，并在一定程度上延长药物在动物体内的循环时间。固态类脂纳米粒可能成为冬凌草甲素的一种新型药物载体。     

肝靶向羟基喜树碱缓释毫微粒的研究

采用吸附—包裹法制备了聚乙烯吡啶烷酮包被的羟基喜树碱聚氰基丙烯酸正丁酯毫微粒。研究了该毫微粒的形态、粒径及粒径分布、载药量、体外释药特征、动物体内的分布与药代动力学参数。结果表明平均粒径dav=81.2nm,载药量为1.22%,体外释药速率符合Higuchi方程:Q=0.0615+0.0940t,静脉注射后15min,即有68.2%羟基喜树碱浓集于肝脏。血浆药浓—时间曲线符合二室开放药动学模型。主要药动学参数为:Vc=3.548L,T_1/2β=146.99h,CL=0.1788L·h^-1。说明该载药毫微粒具有明显的肝靶向和缓释作用。本文报道的吸附─包裹法对水、脂不溶性药物聚氰基丙烯酸酯毫微粒的制备具有一定参考价值。     

PEG-PLA-α-细辛脑纳米粒经鼻腔、静脉给药后的药动学研究

目的 采用与静脉注射对比的方式,研究聚乙二醇-聚乳酸-α-细辛脑纳米粒（PEG-PLA-α-细辛脑纳米粒）鼻腔给药后在大鼠体内的药物动力学。方法 以大鼠为动物模型,采用血药动力学、脑药动力学及荧光标记法对比研究PEG-PLA-α-细辛脑纳米粒经鼻腔给药与静脉注射后药物/纳米粒在大鼠体内的分布情况。结果 PEG-PLA-α-细辛脑纳米粒静脉注射及鼻腔给药后血浆中的AUC_（0-∞）分别为（11032.4±1 827.1）ng·mL^-1·min及（5 992.9±717.5）ng·mL^-1·min,C_max分别为（421.9±100.2）ng·mL^-1及（171.7±26.3）ng·mL^-1,PEG-PLA-α-细辛脑纳米粒鼻腔给药后的绝对生物利用度F为54.3%。PEG-PLA-α-细辛脑纳米粒静脉注射后α-细辛脑在脑组织中的C_max与鼻腔给药后α-细辛脑在脑组织中的浓度C_max分别为（217.9±29.9）ng·mL^-1及（334.2±62.7）ng·mL^-1,PEG-PLA-α-细辛脑纳米粒静脉注射与鼻腔给药后的AUC_brain/AUC_plasma值分别为1.37和2.85,且两者具有统计学意义。PEG-PLA-α-细辛脑纳米粒鼻腔给药后的药物脑靶向效率及鼻-脑传递百分比分别为208.03%及52.01%。荧光标记法结果显示,PEG-PLA-α-细辛脑纳米粒鼻腔给药后脑靶向性比静脉注射后更强。结论 PEG-PLA-α-细辛脑纳米粒适合于鼻腔给药治疗脑部疾病。     

肝靶向米托蒽醌白蛋白微球的研究

用乳化—热固化法制备了米托蒽醌白蛋白微球,并对其形态、大小及其分布、微粉学性质、载药性能、体外释药、稳定性和体内分布进行了研究。结果表明,该载药微球的平均算术径为0.99μm,平均表面径为1.24μm,平均容积径为1.44μm;表观载药量为2.558%±0.101%;有效载药量为1.503%±0.127%;包封率为92.82%±4.60%;体外释药符合双相动力学规律,释药方程为1-Q=0.6428e^-0.2132t+0.3988e^-000150t(γ₁=-0.9951,γ₂=-0.9982);T_1/2α=3.250h,T_1/2β=461.7h;室温放置3个月,微球形态、药物含量等均无明显变化。HPLC测定表明,小鼠尾iv该微球20min内即有77.6%±1.38%的药物浓集于肝脏,具有明显的肝靶向性。提示米托蒽醌白蛋白微球有可能提高米托蒽醌的抗肝癌效果和降低其全身毒副作用。     

盐酸阿霉素聚乳酸纳米粒的制备及大鼠体内药动学研究

目的 优化盐酸阿霉素聚乳酸纳米粒（DOX-PLA-NPs）的制备工艺,并对其理化性质、体外释放及大鼠体内药动学进行研究。方法 采用改良的复乳-溶剂挥发法制备DOX-PLA-NPs,正交设计优化其处方工艺,对其纳米粒形态、粒径、Zeta电位、包封率与载药量进行测定。以DOX原药为对照组,考察DOX-PLA-NPs的体外释药特性及大鼠尾静脉给药后的体内药动学参数。结果 DOX-PLA-NPs外观圆整,平均粒径为（125.67±3.80） nm、Zeta电位为（-35.97±1.58） mV、包封率和载药量分别为（81.23±1.46）%,（10.29±0.63）%。体外释放结果显示,DOX经纳米粒包裹后,具明显的缓释作用。DOX原药和纳米粒的体内药动学过程均符合开放式二室模型,t_1/2β分别为（1.15±0.175） h、（6.43±2.12） h,CL分别为（174.76±47.22） h·L^-1、（30.68±11.86） h·L^-1,AUC_0→t分别为（6.01±1.61）μg·h·L^-1、（36.04±13.72）μg·h·L^-1。结论 制备的盐酸阿霉素聚乳酸纳米粒粒径较小、包封率较高,具明显的缓释作用,并能提高药物的生物利用度。     

葫芦素B-聚乳酸-羟基乙酸共聚物载药纳米粒的构建与药效学评价

目的 以聚乳酸-羟基乙酸共聚物（PLGA）作为纳米制剂载体材料将葫芦素B制备成纳米粒,并考察其对HepG2肝癌细胞的抑制效果。方法 使用乳化溶剂蒸发法制备葫芦素B-PLGA载药纳米粒,以PLGA浓度（X₁）、PVA浓度（X₂）和药物浓度（X₃）作为考察因素,以载药纳米粒的粒径大小（Y₁）和包封率（Y₂）作为评价指标,应用中心复合设计-效应面法优化葫芦素B-PLGA载药纳米粒处方;测定了纳米粒的粒径分布和Zeta电位值,通过透射电镜观察其微观形态,并考察了葫芦素B-PLGA载药纳米粒的体外药物释放特性;比较了葫芦素B与葫芦素B-PLGA载药纳米粒对HepG2肝癌细胞的抑制效果。结果 葫芦素B-PLGA载药纳米粒的最优处方组成为：PLGA浓度为9.0%,PVA浓度为2.0%,药物浓度为4.5%,制备的纳米粒粒径为（145.4±15.8） nm,Zeta电位值为（-7.6±0.8） mV;透射电镜下可观察到纳米粒表面光滑,分布均匀;葫芦素B-PLGA载药纳米粒释药前期出现突释,后期平缓,48 h药物释放达到86%;葫芦素B-PLGA载药纳米粒对HepG2肝癌细胞的抑制作用显著高于葫芦素B。结论 葫芦素B-PLGA载药纳米粒可延缓药物释放,提高对HepG2肝癌细胞的抑制活性,为进一步临床研究奠定实验基础。     

汉黄芩素固体脂质纳米粒在大鼠体内的药动学及组织分布

摘 要 目的:研究汉黄芩素固体脂质纳米粒在大鼠体内的药动学及组织分布情况。方法: 大鼠随机分成汉黄芩素注射液组和汉黄芩素固体脂质纳米粒组,分别于给药后不同时间采血测定汉黄芩素含量,并测定两组大鼠心、肝、脾、肺、肾中汉黄芩素含量,计算靶向效率以评价其在大鼠体内的组织分布及靶向性。结果:汉黄芩素固体脂质纳米粒在大鼠体内的药动学模型符合二室模型,主要药动学参数为：t_1/2α=（0.551 0±0.124 7）h, t_1/2β=(14.589 1±1.563 8)h, CL=(0.006 4±0.001 4) ml·h·Kg^-1, AUC_0→∞=(125.76±9.5728) mg·h·L^-1,其在肝脏、脾脏、心脏、肺脏及肾脏的靶向效率分别为2.003、1.789、0.634、0.707、0.259。结论:与汉黄芩素溶液相比,汉黄芩素固体脂质纳米粒能提高对肝脏、脾脏的趋向性,有利于提高其治疗作用。     

肺靶向利福平聚乳酸微球的研究

在单因素考察的基础上进行正交试验设计,筛选出肺靶向利福平聚乳酸微球的最佳制备工艺条件;利用桨板法研究了微球的体外释药规律;考察了微球在不同温度下的稳定性;用新西兰兔为实验对象,研究了利福平聚乳酸微球的体内药动学及组织药物分布。结果制得的微球形态圆整,粒径在5～15μm范围内的占总体积的86.54%,微球平均粒径为9.00±4.08μm;包封率为31.9%;载药量为16.0%;体外释药方程为Q=20.77+10.12T_1/2(γ=0.9892);微球在冰箱4℃和室温(20～25℃)条件下性质稳定;体内实验表明微球具有长效和肺靶向双重作用。     

肺靶向卡铂明胶微球的研究

目的:为提高卡铂的疗效,降低毒副作用,制备了该药的明胶微球。方法:用乳化法制备卡铂明胶微球,紫外分光光度法测定药物的含量,二阶导数法测定体外释药情况;用静脉注射肿瘤细胞建立了肺肿瘤模型,计算瘤结节数来考察疗效。结果:卡铂明胶微球平均粒径为13-20 μm ,粒径范围5-0～28-6 μm 的微球数占总数的91-8% 。微球平均载药量为23-76%(n=3) 。冰箱、室温和37℃,RH75% 考察3个月,几乎无变化,体外释药符合一级动力学规律,释药T_1/2 比原药延长约10倍。药效学实验表明,卡铂明胶微球对小鼠肺部S180肿瘤生长有明显的抑制作用,抑瘤作用较原药卡铂大大提高。结论:卡铂明胶微球在体内有良好的肺靶向性,对提高药物的疗效,降低药物毒副作用等方面有重大意义。     

5-氟尿嘧啶聚乙二醇-聚十六烷基氰丙烯酸酯纳米粒的制备

目的:以聚乙二醇-聚十六烷基氰丙烯酸酯(PEG-PHDCA)聚合物制备5-氟尿嘧啶(5-Fu)纳米粒,并对其进行体外释药研究.方法:采用溶剂扩散法制备5-Fu PEG-PHDCA纳米粒,在单因素基础上采用正交设计法优化得到最佳处方,并对5-Fu聚合物纳米粒的粒径、Zeta电位、载药量、包封率和体外释放进行了研究.结果:制得的5-Fu聚合物纳米粒的平均粒径为132 nm,Zeta电位为-(12±2)V,载药量为12.3%,包封率为48.8%.体外释放研究发现,5-Fu PEG-PHDCA纳米粒释药近似符合Higuchi释药模型:Q=0.564 4+8.386t1/2(r=0.996 0).结论:采用溶剂扩散法制备5-Fu聚合物纳米粒方法简单,重现性好,其体外释放显示出明显缓释作用.     

Enhanced liver targeting by synthesis of<Emphasis Type="Italic">N</Emphasis><Subscript>1</Subscript>-stearyl-5-Fu and incorporation into solid lipid nanoparticles

To enhance the liver targeting and reduce the side effects of 5-fluorouracil (5-Fu), it was acylated by stearyl chloride to obtain N1-stearyl-5-Fu (5-FuS). The chemical structure of the prodrug was confirmed by Nuclear Magnetic Resonance and Infrared Spectrometry. 5-FuS was incorporated into solid lipid nanoparticles (SLN), which were prepared by the physical agglomeration method. The mean diameter of 5-FuS-SLN was 240.19 nm and the drug loading was 20.53%. The release characteristics in vitro of 5-FuS-SLN were fitted to the first-order pharmacokinetic model. Compared with 5-Fu injection, a study on the distribution of 5-FuS-SLN in mice showed that 5-FuS-SLN could double 5-Fu concentration in mice livers. The main pharmacokinetic parameters of 5-FuS-SLN in rabbits is shown as follows: Vd=0.04336 L/kg, T(1/2) beta=1.2834 h, CL=0.1632 L/h. In conclusion, 5-FuS-SLN has significant liver targeting properties. The employment of a prodrug to enhance drug liposoluble properties and the preparation method presented in this paper, seem to be an alternative strategy to the traditional colloidal delivery system.     

Lectin-mediated cytotoxicity and specificity of 5-fluorouracil conjugated with peanut agglutinin (5-Fu-PNA) in vitro

In order to take advantage of the biorecognition between lectin and carbohydrate for targeted drug delivery, the lectin of peanut (Arachis hypogaea) agglutinin (PNA) was coupled by fixing its amino groups to the carbodiimide-activated carboxylic groups of 5-fluorouracil (5-Fu) derivative (N₁-substituted 5-Fu acetate) to form 5-Fu-PNA conjugate. When the coupling reaction was carried out in the presence of _d-galactose (_d-gal, specific sugar for PNA), the affinity of PNA was maintained after its coupling to N₁-substituted 5-Fu acetate, which was confirmed by the result of the haemagglutination test. Otherwise, PNA would lose its affinity after the cross-linking reaction. The cytotoxicity, specificity and selectivity of 5-Fu-PNA were examined on the human colorectal cancer cell line LoVo and the human normal liver cell line Chang using MTT assay. Compared with free drug, the active conjugate, which maintained the affinity of lectin, had similar cytotoxic effect on LoVo cells with much lower cytotoxicity on Chang cells (p < 0.05). On the other hand, lower cytotoxic effects on LoVo cells were observed for the non-active conjugate even at higher drug concentrations. The cytotoxic effect of conjugate was specific because only the active conjugate could inhibit the growth of LoVo cells in a dose- and time-dependent manner as that of the free drug. The achieved results indicate the significance to maintain the affinity of lectin for lectin-mediated cytotoxicity. Still, the potential of 5-Fu-PNA conjugate as a targeting agent for colorectal cancer needs to be further investigated in vivo.     

In vitro and in vivo evaluation of macromolecular prodrug GC-FUA based nanoparticle for hepatocellular carcinoma chemotherapy

A novel type of macromolecular prodrug delivery system is reported in this research. The N-galactosylated-chitosan-5-fluorouracil acetic acid conjugate (GC-FUA) based nanoparticle delivery system was evaluated in vitro and in vivo. Biocompatibility of GC-FUA-NPs was screened by BSA adsorption test and hemolysis activity examination in vitro. Cytotoxicity and cellular uptake study in HepG2 and A549 cells demonstrated that compared to free 5-Fu, the GC-FUA-NPs play great function in killing cancer cells for the cell endocytosis mediated by asialoglycoprotein receptor (ASGPR), which overexpresses on the cell surface. Pharmacokinetics study further illustrated that the drug-loaded nanoparticles has a much longer half-time than free 5-Fu in blood circulation in Sprague–Dawley (SD) rats. Tissue distribution was investigated in Kunming mice, and the result showed that the GC-FUA-NPs have a long circulation effect. The obtained data suggested that GC-FUA-NP is a very promising drug delivery system for efficient treatment of hepatocellular carcinoma.     

Microwave irradiation synthesis of novel ramose chitosan-based-5-fluorouracil and research on its in vitro release

In order to construct a controlled release system of drugs and to reduce toxic side effects of 5-fluorouracil (5-FU), the novel ramose chitosan-based-5-fluorouracil (CSFU) was synthesized by a two-step method. First, ramose N,N-dicarboxyethyl chitosan (CECS) was efficiently synthesized from chitosan (CS) through microwave irradiation under mild alkaline media. Second, under the catalysis of EDC/NHS and using 5-Fu as a model drug, 1,3-bis(hydroxymethyl)-5-fluorouracil (HMFU) was successfully linked to the ramose CECS. CSFU was characterized by IR spectrum, Raman Spectrum, and UV spectrum. The influence of microwave irradiation time on degree of substitution (DS) of CECS was studied. The content of 5-FU in CSFU and its in vitro release capability in phosphate buffer solution (PBS) were determined by UV spectrum. Results showed the drug loading (DL) was 10.6% and its zero-order release time could sustain 42 h almost without burst release, which indicated its promising application as a potential prodrug in cancer treatment.     

吲哚美辛对5-氟尿嘧啶在大鼠体内药代动力学的影响

目的探讨吲哚美辛(Ind)增强5-氟尿嘧啶(5-Fu)的抗肿瘤作用是否与药代动力学的变化有关。方法采用反相高效液相色谱(HPLC)法测定大鼠血浆中5-Fu浓度,数据用“3p97”程序处理。结果单用和联用Ind后,5-Fu在大鼠体内的药代动力学均为一室模型,t1/2ka分别为(3.8±2.0)和(4.4±2.7)min,t1/2ke分别为(57±46)和(101±48)min,ke分别为(0.018±0.010)和(0.009±0.005)min-1,cmax分别为(7.0±1.8)和(19±8)mg.L-1,AUC分别为(0.7±0.5)和(3.5±2.4)g.min.L-1,Cl分别为(100±50)和(24±21)mg.kg-1.min-1。说明联用Ind后,5-Fu的作用时间延长,在大鼠体内的经时过程增长。结论Ind能延缓5-Fu在大鼠体内的消除,两者联用时应注意调整给药剂量和对5-Fu进行临床给药监测。     

包裹5-氟尿嘧啶的二氧化硅纳米颗粒的制备及细胞毒性研究

目的 制备包裹5-氟尿嘧啶的二氧化硅(5-Fu/SiO₂)纳米颗粒,并对其药剂学参数及体外细胞毒性进行研究。方法 利用反相微乳化法制备5-Fu/SiO₂纳米颗粒,对5-Fu投入量及反应时间等合成条件进行优化,考察纳米颗粒的稳定性及体外释药行为,并采用MTT法对其体外细胞毒性进行研究。结果 当5-Fu投入量为1.33 mg及反应时间为24 h时,5-Fu/SiO₂纳米的载药率及包封率达到最高,分别为1.03%及24.77%,同时该纳米在48 h内释放率达到41.31%,7 d内粒径无明显变化。细胞毒性实验表明,5-Fu/SiO₂纳米对人肝癌细胞具有明显的抑制效果,而空白SiO2纳米对细胞活性影响较小。结论 成功制备了稳定性好、缓释时间长的5-Fu/SiO₂纳米颗粒,为开发5-Fu缓释剂型提供了新的思路。     

缺失错配修复基因MLH1的结直肠癌HCT唱116细胞对氟尿嘧啶耐药机制的研究

目的 研究缺失错配修复基因MLH1（MutL homolog 1）的结直肠癌细胞HCT-116对氟尿嘧啶（5-Fu）耐药机制。方法 通过构建MLH1缺失的结直肠癌细胞HCT-116稳定表达MLH1细胞株,CCK-8试剂检测细胞恢复MLH1表达后对化疗药物5-Fu耐药性的影响,并通过流式细胞仪检测细胞表面干细胞标志CD133和分化标志CK20以及CK8的表达变化。结果 HCT-116稳定表达MLH1分子后,其对5-Fu作用的化疗耐受性降低,5-Fu处理后细胞的活率显著降低（P<0.01）;流式细胞仪检测结果显示CD133表达显著降低,并伴随细胞分化标志CK8和CK20表达上调。结论 结直肠癌细胞缺失错配修复基因MLH1引起5-Fu耐药性可能与其促进肿瘤干细胞样特性密切相关。     

Novel carbopol-based transfersomal gel of 5-fluorouracil for skin cancer treatment: in vitro characterization and in vivo study

Abstract

5-fluorouracil (5-Fu) is an antineoplastic drug, topically used for the treatment of actinic keratosis and nonmelanoma skin cancer. It shows poor percutaneous permeation through the conventionally applicable creams and thus inefficient for the treatment of deep-seated skin cancer. In the present article, transfersomal gel containing 5-Fu was investigated for the treatment of skin cancer. Different formulation of tranfersomes was prepared using Tween-80 and Span-80 as edge activators. The vesicles were characterized for particle size, shape, entrapment efficiency, deformability and in vitro skin permeation. Optimized formulation was incorporated into 1% carbopol 940 gel and evaluated for efficacy in the treatment of skin cancer. 5-Fu-loaded transfersomes (TT-2) has the size of 266.9?±?2.04?nm with 69.2?±?0.98% entrapment efficiency and highest deformability index of 27.8?±?1.08. Formulation TT-2 showed maximum skin deposition (81.3%) and comparable transdermal flux of 21.46?µg/cm²?h. The TT-2-loaded gel showed better skin penetration and skin deposition of the drug than the marketed formulation. Composition of the transfersomal gel has been proved nonirritant to the skin. We concluded that the developed 5-Fu-loaded transfersomal gel improves the skin absorption of 5-Fu and provide a better treatment for skin cancer.     

Preparation and evaluation of N(3)-O-toluyl-fluorouracil-loaded liposomes

This study was aimed at developing a liposome delivery system for a new and potential antitumor lipophilic prodrug of 5-fluorouracil (5-Fu)-N(3)-O-toluyl-fluorouracil (TFu), intended to improve the bioavailability and therapeutic efficacy of 5-Fu by oral and intravenous administration. TFu-loaded liposomes were prepared by a modified film dispersion-homogenization technique, the formulation and manufacture parameters were optimized concerning the drug encapsulation efficiency. TFu-loaded liposomes were characterized according to particle size, size distribution, zeta potential, drug entrapment efficiency, drug loading and physical stability, respectively. In vitro release characteristics, in vivo pharmacokinetic properties and bioavailabilities were also investigated. The formulated liposomes were found to be relatively uniform in size (400.5 +/- 9.6 nm) with a negative zeta potential (-6.4 +/- 0.8 mV). The drug entrapment efficiency and loading were (88.87 +/- 3.25%) and (8.89 +/- 0.19%), respectively. The physical stability experiments results indicated that lyophilized TFu-loaded liposomes were stable for at least 9 months at 4 degrees C. In vitro drug release profile of TFu-loaded liposomes followed the bi-exponential equation. The results of the pharmacokinetic studies in mice indicated that the bioavailability of TFu-loaded liposomes was higher than the suspension after oral administration, and was bioequivalent comparing with TFu 50% alcohol solution after intravenous (i.v.) administration. These results indicated that TFu-loaded liposomes were valued to develop as a practical preparation for oral or i.v. administration.     

氮烯乙茶在成年大鼠肝细胞中的生物转化

目的:建立成年大鼠肝细胞分离培养方法,探讨抗癌新药氮烯乙茶在肝细胞内生物转化。方法:用肝细胞活率、乳酸脱氢酶、能荷值变化观察肝细胞悬浮培养方法的稳定性,以高效液相色谱法测定肝细胞悬液中氮烯乙茶及其代谢产物的浓度。结果:氮烯乙茶在大鼠肝细胞内生成代谢产物7-乙基-8-氨基茶碱(7-ethyl-8-aminotheophylline,EAT) ,其最大反应速度Vm 为12-80 nmol·min^-1/106 cells,米氏常数Km 为640-9 μmol·L^-1 ,氮烯乙茶的固有清除率CLint为20-0 μL·min^-1/106 cells。结论:肝细胞培养的方法是考察药物生物转化的较好体外模型,同时氮烯乙茶具有降低肝细胞能荷值的作用。