Dynamic signal pathway changes of signal transducer and activator of transcription factor-3 in hippocampal neurons induced by oxygen and glucose deprivation in vitro

Abstract

Objective To observe the phosphorylation level and nuclear translocation of signal transducer and activator of transcription factor-3 (STAT3) in hippocampal neurons induced by oxygen and glucose deprivation in vitro and discuss the dynamic changes of STAT3 signal pathway in an in vitro cell model of brain hypoxia and ischemia.Methods Hippocampal neurons from newly born SD rats (within 24 hours from birth) were cultured with DMEM/F12 for nine days,and then were transferred to oxygen and glucose deprivation environment for four hours to establish experimental cell models.The distribution of phosphorylated STAT3 (p-STAT3) in the hippocampal neurons in different groups was observed under laser scanning confocal microscope after immunofluorescence staining.Expression intensity of p-STAT3 at different time points after oxygen and glucose deprivation in the hippocampal neurons was detected by Western blotting.Results Expression of p-STAT3 was unobvious in the nucleus of the control group,but it was observed in the nucleus of the model group one hour after modeling,and peaked at three hour.Expression levels of p-STAT3 in the hippocampal neurons at each time point between the two groups showed significant difference (P ＜ 0.05).Conclusion Oxygen and glucose deprivation induces noticeable up-regulation of p-STAT3 in the hippocampal neuronal nucleus,which indicates the overactivation of signal transduction pathway of STAT3. Key words: Hippocampus ; Neurons ; STAT transcription factors ; Oxygen and glucose deprivation injury