Viability and function of mouse pancreatic cell line. Viability and function of mouse pancreatic cell line. MIN6 cells were cultured to reach 80% confluence, then incubated with different concentrations of streptozotocin (STZ; 0, 1, or 5 mmol/L) with conditioned medium from human exfoliated deciduous teeth (SHED-CM), Dulbecco's modified Eagle's medium (DMEM), exendin-4 (Ex-4; 10 nmol/L), or bone marrow-derived mesenchymal stem cells (BM-CM) for 6 h. Cell damage were examined by nuclear DAPI staining (A) and using the lactate dehydrogenase (LDH) assay (B). The ratio of the total cells to cells with a swollen nucleus was analyzed using the BZ-9000 (A). The results of the LDH assay are expressed as a percentage of LDH release (B). The MTT (3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide) assay was conducted to examine cell survival (C). The MIN6 cells were preincubated with 2.8 mmol/l KRB buffer for 30 min, then stimulated with 2.8 mmol/L (low glucose) or 16.7 mmol/L (high glucose) for 30 min for glucose-stimulated insulin secretion (D). The data are presented as a mean±SEM value. *p<0.05 versus control; †p<0.05 versus Ex-4; §p<0.05 versus BM-CM. Takako Izumoto-Akita et al. BMJ Open Diab Res Care 2015;3:e000128 ©2015 by American Diabetes Association