Abstract: Objective To investigate the effect and mechanism of different concentrations of glucose on apoptosis of mouse hippocampal neuron cell line HT-22. Methods The mouse hippocampal neuron HT-22 cells were cultured in vitro.The cells were treated with different concentrations of sugar medium (25, 35, 45, 55, 65 and 75 mmol/L) for 24 h, 48 h and 72 h, respectively. The reference concentration of 25 mmol/L was used as the control group, and the other groups were the experimental groups. The cell activity was measured by cell counting kit (CCK)-8, and the optimal action time was screened.After HT-22 cells were treated with different sugar concentrations for 48 h, the release rate of lactate dehydrogenase (LDH)in cell culture supernatant was detected by microplate assay. The cell morphology was observed by optical microscope, and the apoptosis rate was determined by flow cytometry. The protein expressions of Bcl-2 and Bax were detected by Western blot assay. Results The results of CCK8 assay showed that high glucose can inhibit the viability of HT-22 cells in a doseand time -dependent manner. When the high glucose action time was 48 h, the cell viability≥80%, which can meet the requirements of subsequent experiments. With the increase of glucose concentration, the number of cells decreased, the cell body became larger, part of the nucleus dissolved and synapse rupture, and the release rate of LDH and apoptosis rate were also increased significantly (P＜0.05). Western blot analysis showed that the expression of apoptosis protein of Bcl-2 decreased (P＜0.05), and the expression of Bax increased gradually (P＜0.05). Conclusion High glucose can significantly inhibit the growth and viability of HT-22 cells and induce apoptosis, which may be related to the expressions of Bcl-2 and Bax.

Key words: glucose, apoptosis, HT-22 cell