Shanghai Municipality Key Laboratory of Veterinary Biotechnology, School of Agriculture and Biology, Shanghai Jiao Tong University, NO.800, Dongchuan Road, Shanghai, 200240, China; Laboratory of Regeneromics, School of Pharmacy, Shanghai Jiao Tong University, NO.800, Dongchuan Road, Shanghai, 200240, China.
Shanghai Municipality Key Laboratory of Veterinary Biotechnology, School of Agriculture and Biology, Shanghai Jiao Tong University, NO.800, Dongchuan Road, Shanghai, 200240, China.
Eur J Pharm Sci. 2020 Apr 30;147:105301. doi: 10.1016/j.ejps.2020.105301. Epub 2020 Mar 9.
Midkine (MK) is a heparin-binding growth factor that functions in multiple physiological processes, making it a promising drug target for treating various diseases including osteoarthritis (OA). However, the lack of pharmacokinetic studies on MK limits further clinical research. As the N-domain of MK protein appears to be more important for its stability, this study aimed to investigate the pharmacokinetic profiles of recombinant human (rh)MK with different structures at the N-terminus via different administration routes in rats and guinea pigs. A single intramuscular (IM) injection of 1 mg/kg rhMK with or without extended sequences at the N-terminus expressed by E. coli or Pichia was administered to six male SD rats. rhMK concentrations in sequential tail blood samples were measured by ELISA. rhMK without extended N-terminal sequences expressed by Pichia had a greater area under the curve (AUC), slower clearance, and longer half-life in rats following a single IM injection than those of the other rhMK proteins. The AUC values for rhMK after IM and intra-articular (IA) administration were 1523.3 ± 35.2 h × ng/mL and 872.0 ± 36.1 h × ng/mL, whereas the apparent volumes of distribution (Vd/f) were 0.184 ± 0.067 L/kg and 11.6 ± 0.8 L/kg, respectively, suggesting that rhMK was distributed more locally after IA injection than after IM injection as Vd/f magnitude gives a general idea of extent distribution in the body and higher Vd/f represents more locally distribution. rhMK concentration in the articular cartilage was markedly higher than that in serum and reached the highest level at 3 days after a single IA injection in Hartley guinea pigs. As the dose increased from 10 to 50 mg/kg, the AUC increased in a greater-than-dose-proportional manner, suggesting that rhMK exhibits non-linear pharmacokinetics in rats after a single IM injection in this dose range. These results indicated that the N-terminal structure and administration route have substantial effects on the pharmacokinetics of rhMK in rats. Furthermore, rhMK was maintained in articular cartilage with minimal diffusion into the blood following IA injection in Hartley guinea pigs, providing a foundation for clinical research on the use of rhMK for OA treatment via IA delivery.
中期因子 (MK) 是一种肝素结合生长因子，在多种生理过程中发挥作用，使其成为治疗包括骨关节炎 (OA) 在内的各种疾病的有前途的药物靶点。然而，MK 的药代动力学研究的缺乏限制了进一步的临床研究。由于 MK 蛋白的 N 结构域似乎对其稳定性更为重要，因此本研究旨在通过不同的给药途径在大鼠和豚鼠中研究具有不同 N 末端结构的重组人 (rh)MK 的药代动力学特征。 向六只雄性 SD 大鼠单次肌内 (IM) 注射 1mg/kg 的 rhMK，或在大肠杆菌或毕赤酵母中表达的具有 N 末端延长序列的 rhMK。 通过 ELISA 测量连续尾血样本中的 rhMK 浓度。与其他 rhMK 蛋白相比，毕赤酵母表达的无 N 末端延长序列的 rhMK 在大鼠单次 IM 注射后具有更大的 AUC、更慢的清除率和更长的半衰期。IM 和关节内 (IA) 给药后 rhMK 的 AUC 值分别为 1523.3 ± 35.2 h×ng/mL 和 872.0 ± 36.1 h×ng/mL，而表观分布体积 (Vd/f) 分别为 0.184 ± 0.067 L/kg 和 11.6 ± 0.8 L/kg，这表明 rhMK 在 IA 注射后比 IM 注射后更局部分布，因为 Vd/f 幅度给出了体内广泛分布的概念，而更高的 Vd/f 表示更局部的分布。在单次 IA 注射后 3 天，Hartley 豚鼠关节软骨中的 rhMK 浓度明显高于血清中的浓度，并达到最高水平。随着剂量从 10 增加到 50mg/kg，AUC 以大于剂量比例的方式增加，表明在该剂量范围内，rhMK 在大鼠单次 IM 注射后表现出非线性药代动力学。这些结果表明，N 末端结构和给药途径对大鼠 rhMK 的药代动力学有显著影响。此外，rhMK 在 Hartley 豚鼠中通过 IA 注射后在关节软骨中保持，很少扩散到血液中，为 rhMK 通过 IA 给药治疗 OA 的临床研究提供了基础。
