肝素结构与抗人肾小球系膜细胞增殖活性的关系

目的：考察肝素结构中影响抗人系膜细胞增殖活性的因素．如不同位点的硫酸基团，整基、肝索的主链结构以及相对分子质量大小.方法：采用化学修饰的方法，分别制备2，3-O-脱硫酸化，6-O-脱硫酸化肝紊，N-脱硫酸化肝素．高碘酸钠氧化-硼氢化钠还原肝素、多硫酸化肝素，APTT比较肝表衍生物的抗凝活性，MTT法比较这些肝素衍生物对血清引起人肾小球系膜细胞增殖的抑制作用结果和结论：2，3-O-硫酸基团相对于6-O-硫酸基团、N-硫酸基团采说对抗血清引起的人肾小球系膜细胞增殖活性影响更大．硫酸基团的含量以及羧基影响抗增殖活性，但不是决定性的因素．肝素抗增殖活性同样不依赖于肝素主链结构的完整性、抗凝活性；当肝素相对分子质量大于4．5kD时，其杭增殖活性同样不依赖于其相对分子质量大小

Structural Determinants of the Antiproliferative Effect of Heparin Molecule on Human Mesangial Cell

AIM: To determine the structural determinants of the antiproliferative effect of heparin molecules on human mesangial cell. METHODS: Unfractionated heparin was separately desulfated, periodate-oxidized/borohydride-reduced, carboxyl-reduced and poly-sulfated by chemical modification. These heparin derivates were assayed for antiproliferative effects on cultured human mesangial cell compared with unfractionated heparin. RESULTS and CONCLUSION: 2, 3-O-desulfated heparin almost completely lost the antiproliferative activity at concentration between 0.01～1.5 mg·mL-1, 6-O-desulfated, N-desulfated and carboxyl-reduced heparin significantly lost some activities compared with heparin, but periodate-oxidized/borohydride-reduced, poly-sulfated heparin and enoxaparin exhibited comparable growth-inhibition effects on human mesangial cell. The anticoagulation activity of heparin derivates markedly decreased by APTT. These data suggest that 2-O- or 3-O-sulfation is much more important than 6-O- and N-sulfation to antiproliferative activity. Sulfate and carboxyl are factors but not essential reasons. Antiproliferative effect is also independent on heparin polysaccharide chain, anticoagulation activity and molecular size exceeding 4.5 kDa.