Evaluation of angiogenic activities of hyaluronan oligosaccharides of defined minimum size

AimsOligosaccharides of hyaluronan (o-HAs) were proved to have pro-angiogenic activities. The aim of this study was to obtain four hyaluronan oligosaccharides (o-HAs) of defined molecular weight including 4 saccharide residues (o-HA4), 6 saccharide residues (o-HA6), 8 saccharide residues (o-HA8), and 10 saccharide residues (o-HA10) under optimum conditions, and compare their angiogenic activities.Main methodsThe four o-HAs were prepared by digesting the native high molecular weight HA with hyaluronidase under optimum conditions. The effects of the four o-HAs on human umbilical vein endothelial cell (HUVEC) proliferation were measured using 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenil tetrazolium bromide (MTT) assay. Angiogenic effects of the four o-HAs were evaluated using chicken chorioallantoic membrane (CAM) assay. The effects of the four o-HAs on the vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) messenger ribonucleic acid (mRNA) expressions were detected by semi-quantitative polymerase chain reaction (PCR).Key findingsO-HA6, o-HA8 and o-HA10 could effectively promote the proliferation of HUVEC, induce angiogenesis in the CAM assay and increase VEGF mRNA levels in HUVEC. No significant effects were found with o-HA4.SignificanceThese results suggested that o-HA6, o-HA8, and o-HA10, but not o-HA4 were effective angiogenic factors.