果胶多柔比星纳米混悬剂的制备及初步药效评价

Preparation and evaluation of pharmacodynamic of the pectin-doxorubicin conjugate nanosuspensions

运用高压均质技术制备果胶多柔比星轭合物(pectin-doxorubicin conjugate,PDC)纳米混悬液,评价其理化性质、体外释放、体内释放及抗肿瘤活性。以纳米粒平均粒径及多分散指数(polydispersity index,PI)为指标,研究各影响因素如压力、循环次数和稳定剂种类对PDC纳米混悬剂的影响。考察PDC纳米混悬液在p H为5.1或7.4的磷酸盐缓冲液(phosphate buffer saline,PBS)中的累积释放率。腹腔注射多柔比星(doxorubicin,DOX)当量为10 mg·kg^(-1)的PDC纳米混悬液或10 mg·kg^(-1) DOX,测定家兔血浆中DOX浓度。构建SKOV3细胞裸鼠模型,腹腔注射DOX当量为10、5、2.5 mg·kg^(-1)的PDC纳米混悬液,观察裸鼠生长状态。结果表明:PDC纳米混悬剂的平均粒径为118.8±6.93 nm,PI为0.14±0.03,zeta电位为-27.2±0.36 m V。PDC纳米混悬液在p H 7.4的PBS中基本不释放,在p H 5.1时,30 h内累积释放率约40%。腹腔给药后,PDC组家兔血浆中DOX浓度低于DOX组,呈现先升高后降低的趋势,最终维持在60 ng·m L-1左右。此外,PDC纳米混悬液能有效抑制SKOV3细胞裸鼠移植瘤的生长,高剂量组裸鼠腹水瘤及瘤结节重量比阴性对照组显著减少。综上,PDC有望开发成一种高效低毒的靶向治疗癌性腹水的新型药物。

This study was conducted to produce pectin-doxorubicin conjugate （PDC） nanosuspensions by high-pressure homogenization, and investigating the physico-chemical properties, the cumulative release rate in vitro and in vivo, and the anti-tumor activity. The major production parameters such as pressure, cycle numbers and types of stabilizers on the mean particle size and polydispersity index （PI） of PDC nanosuspensions were investigated. The cumulative release rate in phosphate buffer saline （PBS） at pH 5.1 or 7.0 were studied. The concentration of doxorubicin （DOX） in plasma of rabbit were recorded after intraperitoneal injection of PDC nanosuspensions （DOX was equivalent to 10 mg ·kg-1） or DOX （10 mg·kg-l）. We established an animal model of the nude mice with SKOV3 cell, and injected the PDC nanosuspensions （DOX was equivalent to 10, 5, 2.5 mg·kg-1 in the first day, and observed the growth state of nude mice. The particle size of PDC nanosuspensions was 118.8±6.93 nm, PI was 0.14±0.03, as well as the zeta potential was -27.2±0.36 inV. It shows that no drug release was found in PBS at pH 7.4. About 40% cumulative release was determinedin PBS at 5.1 after 30 h. The concentration of DOX in plasma of PDC group was 60 mg ·kg-1, and was lower than that of DOX group. Compared with control group, high-dose-group decreased the weight of nude mice＇s ascites tumor and burrknot. PDC nanosuspensions can inhibit the growth of SKOV3 cell line in nude mice. In summary, PDC nanosuspensions are target-specific drugs with high efficiency and low toxicity in the ascites cancer model.