鲑鱼来源的聚脱氧核苷酸分子量分布对其生物学活性的影响

Effect of molecular weight distribution of polydeoxyribonucleotides derived from salmon on its biological activity

目的分析鲑鱼来源的聚脱氧核苷酸分子量分布对其生物学活性的影响。方法采用乙醇分级沉淀去纤苷类似物（defibrotide analogue,DFA）,收集三步分级沉淀样品,脱水烘干,即H、M、L组分,体积排阻高效液相色谱（HPLC）法测定其分子量分布,S-2251底物法检测各分级组分对纤溶酶活性的影响,经典魏氏法检测各分级组分对红细胞沉降率的影响。结果获得H、M、L组分分别为0.46、1.03和0.38 g,80%H、M及L组分聚脱氧核苷酸链长分布分别为60~100、30~50及小于25 nt。DFA及H、M组分均可提高纤溶酶活性,与各组分分子量、浓度呈正相关,但L组分促纤溶活性不明显。与对照组相比,DFA及各分级组分均可引起红细胞沉降率显著升高,并呈剂量-效应关系,差异有统计学意义（P〈0.05）。结论分子量分布是影响DFA活性的关键因素,为天然来源的聚脱氧核苷酸活性产物的筛选提供了参考。

Objective To analyze the effect of molecular weight distribution of polydeoxyribonucleotides derived from salmon on its biological activity. Methods Defibrotide analogue（DFA） was precipitated fractionally with ethanol. The samples of three fractions（H, M and L） were collected, dehydrated and dried, then determined for molecular weight distribution by size exclusion HPLC, for fibrinolysin activity by S-2251 chromogenic substrate method, and for erythrocyte sedimentation rate by Westergren method. Results Fractions H, M and L, with weights of 0. 46, 1. 03 and 0. 38 g respectively, were obtained, in 80% of which the lengths of polydeoxyribonucleotides were 60 ~ 100, 30 ~ 50 and less than 25 nt respectively. DFA as well as fractions H and M increased the fibrinolysin activity in molecular weight- and concentration-dependent patterns, while fraction L showed no significant promoting effect on the activity. DFA and its fractions increased the erythrocyte sedimentation rate in dose-dependent pattern as compared with those in control group（P 〈 0. 05）. Conclusion Molecular weight distribution is a key influencing factor of biological activity of DFA. This study provided a reference for screening of biologically active polydeoxyribonucleotides from natural origin.