RGD肽类似物的合成及活性测定

Synthesis and Activities of RGD Peptide Analog

目的合成RGD(精氨酸-甘氨酸-天门冬氨酸)肽类似物-AoGDw(ω-氨基辛酸-甘氨酸-天门冬氨酸-色氨酸),研究其结构对血小板聚集功能的影响。方法采用固相法合成AoGDW,经Sephadex G-10纯化,RP-HPLC(反相高效液相色谱法)、质谱和氨基酸组成分析对其进行鉴定,并采用比浊法测定其抗血小板聚集的活性及稳定性。结果获得了纯度为98.3%的目的肽、质谱和氨基酸组成分析结果均与理论值一致。AoGDW及对照组抑制血小板聚集的IC_(50)分别为(4.7l±2.51)和(61.82±8.08)μmol·L^(-1)在血浆中孵育3 h,仍保持100%的活性。结论AoGDW具有更强的抗血小板聚集的活性及稳定性,说明与RGD序列紧邻的氨基酸残基对其功能有重要的影响。

OBJECTIVE To synthesize RGD （arginine-glycine-aspartic acid-tryptophan） peptide analog-AoGDW （to-aminooctanoic acid-glycine-aspartic acid-tryptophan） and investigate its effect on inhibiting platelet aggregation. METHODS AoGDW was synthesized by solid phase method and purified on Sephadex G- 10. The synlhesized peptide was identified by RP-HPLC （reversedphase high performance liquid chromatography）. The structure of peptide was confirmed by MS （mass spectrograph） and amino acid analysis. The activity and stability of antiplatelet aggregation of AoGDW were studied using aggregolneter and expressed as percentage change in light transmiuance. RESULTS The purity of purified peptide was 98.3%. Peptide structure verified through MS and amino acid analysis was consistent with theory, IC50 ,values of inhibiting platelet aggregation of AoGDW and control group were （4.71 ± 2. 51 ） and （61.82 ± 8.08） μmol · L^-1. AoGDW was achieved with improved plasma stability （ 100% activity after 3 h）. CONCLUSION AoGDW was highly active, highly steady inhibitor of platelet aggregation, which suggests the side chains and backbone elements of residues flanking the RGI） sequepce may play very important effects on its function.