Original Article
Damage effect of intermittent high glucose on rat islet cell tumor cell line Ins-1 and its impacts on the expression of phosphatase and tensin homologue deleted on chromosome 10 in those cells
Chen Shao, Xiaoli Wang, Difei Wang, Guojiao Li, Yan Guo, Yumei Dong
Published 2015-11-27
Cite as Chin J Diabetes Mellitus, 2015, 07(11): 689-693. DOI: 10.3760/cma.j.issn.1674-5809.2015.11.007
Abstract
ObjectiveTo study the effect of intermittent hyperglycemia on rat insulinoma cell line Ins-1 apoptosis and the expression of phosphatase and tensin homologue-deleted chromosome ten gene (PTEN) in those cells.
MethodsIns-1 cells were divided into three groups: control group (CG, cultured in 11.1 mmol/L glucose), sustained high glucose group (SHG, cultured in 33.3 mmol/L glucose) and intermittent high glucose group (IHG, cultured in 33.3 or 11.1 mmol/L glucose each for 12 h) respectively. After three days of incubation, cell viability was determined by Owen's reagent(MTS), apoptosis rate was detected by flow cytometry after staining with Annexin V/PI, insulin secretion was measured but radioimmunoassay, intracellular reactive oxygen species(ROS) was detected by DCFH-DA fluorescence probe, the morphology of cells of the three groups were observed under inverted phase contrast microscope. The data was compared with one-way ANOVA analysis.
ResultsCompared with CG group, the cellular apoptosis rate, intracellular ROS levels, calcium levels, and the expressions of PTEN protein in cells of SHG group were all significantly increased (t=8.310, 10.261, 17.890, 5.123, all P<0.05), while cell viability and insulin secretion decreased significantly(t=-19.630, -2.053, both P<0.05). However, compared to both of the CG group and the SHG group, the cellular apoptosis rate, intracellular ROS levels, intracellular calcium levels, and the expression of PTEN protein in cells of IHG group increased significantly(t=6.20-18.227, all P<0.05), while cell viability and insulin secretion decreased significantly(t=-27.800, -2.79, -8.167, -1.503, all P<0.05). Compared to CG group and the SHG group, the pleomorphism of the cells, the reduction in cell number and the disarrangement of cells in the IHG group were all the most significant.
ConclusionsOxidative stress may play an important role in the apoptosis of Ins-1 cells under high glucose environment and it may be related to the high expressions of PTEN. The adverse effect of intermittent high glucose on the Ins-1 cell-line may be greater than that of sustained high glucose.
Key words:
Intermittent hyperglycemia; Rat islet cell tumor cell line Ins-1; Phosphatase and tensin homologue-deleted chromosome ten gene
Contributor Information
Chen Shao
Department of Endocrinology and Metabolism, the First Affiliated Hospital of China Medical University, Shenyang 110001, China
Xiaoli Wang
Difei Wang
Guojiao Li
Yan Guo
Yumei Dong
