Abstract: Abstract:　Objective　To investigate the effect of high glucose on the proliferation and oxidative stress of human dental pulp cells(HDPCs), and to explore the influencing mechanism of high glucose environment on dental pulp. Methods　Dental pulp cells were isolated and cultured, and the source of tissue was identified. The experiment was divided into four groups:low-glucose group(glucose 5.5 mmol/L), normal group(25 mmol/L), high-glucose group(50 mmol/L), and hyperosmolar group(osmotic pressure was equal to that of the 50mmol/L group and glucose concentration was equal to that of the 5.5 mmol/L group). CCK-8 kits were used to detect the proliferation level of HDPCs after 1 day, 3, and 5 days. DCFH-DA was used to detect intracellular ROS level after treatment with high glucose, the content of malondialdehyde(MDA) was measured by enzyme labeling method, and the activity of superoxide dismutase(SOD) was measured by Water-soluble tetrazolium method. Flow cytometry was used to analyze mitochondrial membrane potential in each group. Results　①Compared with the normal group, high glucose had significant inhibitory effect on the proliferation of HDPCs(P<0.05). ②The levels of reactive oxygen species(ROS) and malondialdehyde(MDA) increased significantly after exposure to 50 mM glucose for 72 h, and activity of superoxide dismutase(SOD) decreased. Compared with the normal group, there was a statistical difference(P<0.05).③ Flow cytometry detection of mitochondrial membrane potential showed that the fluorescence value of high glucose group was higher than that of normal group(P<0.05). Conclusion　High glucose can inhibit the proliferation of pulp cells, and lead to the decrease in mitochondrial membrane potential of HDPCs, induce oxidative stress, indicating that the high-glycemic environment reduces the vitality of dental pulp cells, which may also be a potential factor for the change of dental pulp tissues in diabetic patients.

Key words: high glucose, human dental pulp cell, oxidative stress, mitochondrial membrane potential