Protective Effects Of Polysaccharides Of Dendrobium Candidum On High Glucose-induced Oxidative Damage In Cultured Human Umbilical Vein Endothelial Cells

OBJECTIVE:To observe the protective effects of polysaccharides of dendrobium candidum(PDC) on high glucose-induced oxidative stress damage in cultured humanumbilical vein endothelial cells (HUVECs).METHODS:The cultured HUVECs were used to investigate the protective effects ofpolysaccharides of dendrobium candidum on high glucose-induced damage.HUVECs were treated with high glucose (33.3mmol/L) for48h to induce the injury.Meanwhile, HUVECs were treated with PDC (100,200and400μg/mL) for48h.The cells were divided into the control group, high glucose group, differentconcentration PDC (100,200and400μg/mL) group and high glucose+differentconcentration PDC (100,200and400μg/mL) group. The cell viability was detectedby MTT assay. The cell culture medium was collected, and the content of nitrogenmonoxidum (NO) and the activity of superoxide dismutase (SOD) in culturemedium were detected. The mitochondrial membrane potential (MMP), level ofintracellular Ca2+and reactive oxygen species (ROS) were measured byfluorescence flow cytometry.RESULTS:(1) Compared with the control group, the cell viability was significantlydecreased (P<0.05), MMP was significantly decreased (P<0.01), level ofintracellular Ca2+was significantly increased (P<0.01), level of intracellular ROSwas significantly increased (P<0.05), the activity of SOD was significantlydecreased (P<0.05), the content of nitrogen NO was significantly decreased (P<0.05)in high glucose group.(2) Compared with the control group, PDC (50,100,200,400and800μg/mL) did not affect the cell viability and apoptosis of HUVECs (all P＞0.05).(3) Compared with the high glucose group, the cell viability was significantlyincreased in concentration dependent manner (all P<0.05), MMP was significantlyincreased in concentration dependent manner (all P<0.05), level of intracellular Ca2+was significantly decreased in concentration dependent manner (all P<0.05), level ofintracellular ROS was significantly decreased (P<0.05), the activity of SOD wassignificantly increased (P<0.05), the content of nitrogen NO was significantlyincreased in concentration dependent manner (all P<0.05) in high glucose+differentconcentration PDC (100,200and400μg/mL) group.CONCLUSIONS:Polysaccharides of dendrobium candidum inhibits the oxidative stress inducedby high glucose in cultured human umbilical vein endothelial cells.