Fig. 2: miR-422a inhibition attenuates OGD/R-induced neuronal cell death and apoptosis.

SH-SY5Y cells were infected with pre-miR-422a anti-sense lentivirus (“lv-antagomiR-422a”) or non-sense miR inhibitor control lentivirus (“lv-antagomiR-C”) for 24 h, followed by puromycin selection (4–5 passages) to establish stable cells. Cells were maintained under oxygen glucose deprivation (OGD) for 4 h, followed by re-oxygenation (“OGD/R”) for the applied time; miR-422a expression (a), cell viability (b), cell death (c), cleaved-/or total-caspase-3/-PARP expression (d) and cell apoptosis (e) were tested by the assays mentioned in the text, with mitochondrial depolarization examined by JC-1 staining assay (f). The primary murine neurons were transfected with non-sense miR inhibitor control (“antagomiR-C”, 100 pmol × two rounds) or miR-422a inhibitor oligonucleotides (“antagomiR-422a”, 100 pmol × two rounds), followed by the same OGD/R procedure for applied time; miR-422a expression (g) and cell death (medium LDH release, h) were tested; Cell apoptosis and mitochondrial depolarization were tested by TUNEL staining (i) and JC-1 assay (j), respectively. Data indicate standard deviation (SD, n = 5). *p < 0.05 vs. “Mock” cells. ^#p < 0.05 vs. OGD/R-treated “lv-antagomiR-C”/“antagomiR-C” neuronal cells. Each experiment was repeated three times and similar results were obtained. Bar = 100 μm (f, i and j).