Abstract：
The intrinsic tenase complex (iXase) is an attractive antithrombotic target to treat or prevent pathological thrombosis with negligible bleeding risk. Fucosylated glycosaminoglycan (FG) is a promising anticoagulant by inhibiting iXase. A depolymerized FG (dHG-5) as an anticoagulant has been approved for clinical trials. Given that dHG-5 is a multi-component drug candidate consisting of a homologous series of oligosaccharides, it is difficult to predict a clear pharmacokinetics. Here, as a major oligosaccharide component, the tetradecasaccharide (oHG-14) was purified from dHG-5 and its structure was defined as L-Fuc3S4S-α(1,3)-L-Δ4,5GlcA-α(1,3)-{D-GalNAc4S6S-β(1,4)-[L-Fuc3S4S-α(1,]3)-D-GlcA-β(1,3)-}3-D-GalNAc4S6S-β(1,4)-[L-Fuc3S4S-α(1,]3)-D-GlcA-ol. oHG-14 showed potent iXase inhibitory activity in vitro and antithrombotic effect in vivo comparable to dHG-5. After single subcutaneous administration of oHG-14 at 8, 14.4 and 32.4 mg/kg to rats, the absolute bioavailability was 71.6 %-80.9 % determined by the validated bioanalytical methods. The maximum concentration (Cmax) was 3.73, 8.07, and 11.95 μg/mL, respectively, and the time reaching Cmax (Tmax) was about 1 h. oHG-14 was mainly excreted by kidney as the parent compound with the elimination kinetics of first-order linear model. Anticoagulant activity of oHG-14 was positively correlated with its concentration in rat plasma. The pharmacokinetics/pharmacodynamics (PK/PD) of oHG-14 is similar to that of dHG-5. This study could provide supportive data for the clinical trial of dHG-5 and further development of pure oligosaccharide as an antithrombotic drug candidate.
摘要：
内在tenase复合物（iXase）是治疗或预防病理性血栓形成的有吸引力的抗血栓形成靶标，出血风险可忽略不计。岩藻糖基化糖胺聚糖（FG）通过抑制iXase是一种有前途的抗凝剂。解聚的FG(dHG-5)作为抗凝剂已被批准用于临床试验。鉴于DHG-5是由同源系列寡糖组成的多组分候选药物，很难预测明确的药代动力学。这里,作为主要的寡糖成分，从dHG-5中纯化出十四糖（oHG-14），其结构定义为L-Fuc3S4S-α（1,3）-L-Δ4,5GlcA-α（1,3）-{D-GalNAc4S6S-β（1,4）-[L-Fuc3S4S-α（1，]3）-D-GlcA-S-4-oHG-14在体外显示出有效的iXase抑制活性，在体内显示出与dHG-5相当的抗血栓形成作用。在对大鼠单次皮下施用8、14.4和32.4mg/kg的oHG-14后，通过经过验证的生物分析方法确定的绝对生物利用度为71.6%-80.9%.最大浓度（Cmax）为3.73、8.07和11.95μg/mL，分别,达到Cmax（Tmax）的时间约为1h。oHG-14主要由肾脏作为母体化合物排泄，消除动力学为一阶线性模型。oHG-14的抗凝活性与其在大鼠血浆中的浓度呈正相关。oHG-14的药代动力学/药效学(PK/PD)与dHG-5相似。本研究可为dHG-5的临床试验和进一步开发纯寡糖作为抗血栓候选药物提供支持数据。
