Overexpression of cytoglobin gene inhibits hypoxic injury to SH-SY5Y neuroblastoma cells

A plasmid for cytoglobin expression, pAcGFP1-C1-cytoglobin, was transfected into SH-SY5Y cel s. Cobalt chloride was used to establish a model of hypoxia. Western blotting indicated that cytoglobin was overexpressed and there was low expression of hypoxia-inducible factor-1αin SH-SY5Y cel s after transfection. Fol owing cobalt chloride-induced hypoxia, cytoglobin and hypoxia-inducible fac-tor-1αexpression gradual y increased in SH-SY5Y cel s. Flow cytometry showed that with increas-ing duration of hypoxia, the proportion of normal cel s significantly diminished in the transfected and non-transfected groups. The proportion of cel s in the early stages of apoptosis increased. However, the proportion of apoptotic cel s was significantly lower in the transfected group compared with the non-transfected group. These results demonstrate that cytoglobin and hypoxia-inducible factor-1αare strongly up-regulated by hypoxia, and that there is a strong relationship between hypox-ia-inducible factor-1αand cytoglobin during hypoxic injury.