The Beneficial Effect of Melatonin in Brain Endothelial Cells against Oxygen-Glucose Deprivation Followed by Reperfusion-Induced Injury
Figure 1
The measurement of brain endothelial cell viability after OGD/R-induced injury. (a) A 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay shows that bEND.3 cells in the OGD/R injury exposed group exhibited decreased viability compared to cells in the normal control group. Cell viability of bEND.3 cells in 1 nM and 5 nM melatonin pretreatment groups was not largely different form OGD/R injury exposed group. bEND.3 cells in 10 nM, 50 nM, and especially 100 nM melatonin pretreatment groups exhibited increased cell viability compared to OGD/R injury exposed group. Data are expressed as mean ± S.E.M. (#, *, and **). (b) Cytotoxicity (%) was measured using an LDH assay. Cytotoxicity increased in OGD/R injury exposed group compared to the normal control group. Melatonin treatment (especially 100 nM melatonin pretreatment) reduced cytotoxicity after OGD/R injury. Data are expressed as mean ± S.E.M. (#, *, and **). (c) Dead and live cells were measured by Hoechst/PI staining. PI-positive cells (red) are regarded as the dead cells. PI-positive cells were higher in OGD/R injury exposed group than in the normal control group. Melatonin treatment groups (both in 10 nM and in 100 nM melatonin groups) exhibited reduced PI-positive cells compared to the OGD/R injury exposed group. Hoechst: Hoechst 33342 (blue color) and PI: propidium iodide (red color). Scale bar = 400 µm.
