Laboratory of Ethnopharmacology, Regenerative Medicine Research Center, West China Hospital/West China Medical School, and Institute for Nanobiomedical Technology and Membrane Biology, Sichuan University, Chengdu 610041, China.
J Chromatogr B Analyt Technol Biomed Life Sci. 2013 Jul 15;931:1-5. doi: 10.1016/j.jchromb.2013.05.005. Epub 2013 May 14.
Deltonin is a naturally occurring spirostanol glycoside from Dioscorea zingiberensis C.H. Wright, which is used in traditional Chinese medicine. It exerts strong cytotoxic effect on C26 cells, inhibits C26 derived-tumor growth, and prolongs the survival of tumor-bearing mice after its oral administration, indicating its potential for use as an anti-tumor drug. To investigate the pharmacokinetic profiles of deltonin, a rapid, sensitive, and simplified high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) assay was developed and validated for the determination of deltonin in rat plasma. After acetonitrile-mediated plasma protein precipitation, chromatographic separation of deltonin was achieved using a reversed phase Hypersil Gold column (150mm×2.1mm, 5μm), with gradient elution using 0.1% formic acid and acetonitrile. Thereafter, deltonin was quantified using MS/MS with electrospray ionization (ESI) in positive multiple reaction monitoring (MRM) mode. The flow rate of the mobile phase was 200μL/min, and the retention time was 9.03min for deltonin and 6.31min for the internal standard (IS: 20(S)-ginsenoside Rb1). The linear range of the calibration curve was 2-5000ng/mL (r(2)>0.99), and the limit of detection (LOD) was 0.46ng/mL. The intra- and inter-day accuracies ranged from -2.8% to 11.1% and precisions (RSD) were within 13.1%. Deltonin was found to be stable under short-term temperature conditions, post-preparative temperature conditions, and after 3 freeze-thaw cycles conditions. The validated method was successfully applied to a pharmacokinetic study in rats after oral administration of deltonin (50 and 100mg/kg). The pharmacokinetics is characterized by high apparent clearance (CL/F) and apparent volume of distribution (Vd/F).
盾叶薯蓣中的天然甾体皂甙元糖苷 deltonin 可用于传统中药，对 C26 细胞具有很强的细胞毒性作用，抑制 C26 衍生肿瘤的生长，并延长荷瘤小鼠的存活时间，表明其具有作为抗肿瘤药物的潜力。为了研究 deltonin 的药代动力学特征，开发并验证了一种快速、灵敏、简化的高效液相色谱-串联质谱（HPLC-MS/MS）测定大鼠血浆中 deltonin 的方法。用乙腈介导的血浆蛋白沉淀后，采用反相 Hypersil Gold 柱（150mm×2.1mm，5μm）进行色谱分离，用 0.1%甲酸和乙腈进行梯度洗脱。然后，采用电喷雾电离（ESI）正多重反应监测（MRM）模式的 MS/MS 定量分析。流动相的流速为 200μL/min，deltonin 的保留时间为 9.03min，内标（IS：20(S)-ginsenoside Rb1）的保留时间为 6.31min。校准曲线的线性范围为 2-5000ng/mL（r(2)>0.99），检测限（LOD）为 0.46ng/mL。日内和日间准确度的范围为-2.8%至 11.1%，精密度（RSD）在 13.1%以内。在短期温度条件、制备后温度条件和 3 次冻融循环条件下，deltonin 均稳定。该验证方法成功应用于大鼠口服 50 和 100mg/kg deltonin 后的药代动力学研究。药代动力学的特点是高表观清除率（CL/F）和表观分布容积（Vd/F）。
