毛细管区带电泳法考察牛凝血酶、核酸适配体与丹参活性分子间的相互作用

采用毛细管区带电泳法(CZE)研究牛凝血酶(B-Thr)、凝血酶核酸适配体(Apt29)与丹参中3种活性物质(丹参素钠(SAS)、原儿茶酸(PA)、阿魏酸(FA))间的相互作用。电泳条件为:毛细管长度40 cm,紫外检测波长214 nm,分离电压15 kV,压力进样3.45 kPa,进样时间5 s。分别固定3种活性药物分子的浓度,改变B-Thr或Apt29的浓度,采用Scatchard方程和非特异性结合方程计算结合常数(K_b),表征药物分子和B-Thr或Apt29的相互作用大小。结果表明,PA与B-Thr结合能力最强,K_b为3.39×104L/mol,FA与B-Thr的K_b为1.05×104L/mol,SAS与B-Thr未表现出结合能力;在与Apt29的相互作用的研究中显示,SAS基本未与Apt29结合,FA与Apt29结合能力强于PA与Apt29的结合能力,FA、PA与Apt29的K_b分别为1.48×104L/mol和1.32×104L/mol。该研究报道了丹参活性分子与B-Thr、Apt29的相互作用结果,可为核酸适配体(蛋白质)与中药分子相互作用的探索提供新方法,适配体与中药分子相互作用亦可为中药分子的靶点发现、靶向转运提供借鉴。

Investigation on interactions between bovine thrombin,aptamer and active components in Danshen by capillary zone electrophoresis

Investigation on interactions between bovine thrombin (B-Thr), aptamer29 (Apt29) and three active components (salvianic acid A sodium (SAS), protocatechuic acid (PA), ferulic acid (FA)) in Danshen was carried out by capillary zone electrophoresis (CZE). CZE conditions were as follows: capillary length of 40 cm, voltage of 15 kV, injection volume of 3.45 kPa, injection time of 5 s. By changing concentration of B-Thr or Apt29 with fixed levels of the three active components, binding constants (K_b) were calculated by Scatchard and non-specific binding equations to show interactions between B-Thr, Apt29 and the three active components. The results showed that PA had the strongest affinity to B-Thr with K_b 3.39×10⁴L/mol. K_b between FA and B-Thr was 1.05×10⁴ L/mol. SAS had no binding with B-Thr. FA showed stronger affinity with Apt29 than PA with K_b of 1.48×10⁴ L/mol and 1.32×10⁴ L/mol, respectively. The present study reported that interactions between the active constituents in Danshen and B-Thr/Apt29. New methods might be supplied for calculation of interactions between Apt (protein) and herbal drug molecules. And it could give insight for target discovery and delivery of herbal drug molecules.