Abstract:

BACKGROUND: In the aging process, the changes of environment in the brain can cause changes in proliferation ability of brain neural stem cells. The neural stem cells are closely associated with senescence and neurodegenerative diseases. Proliferation ability is negatively correlated with age. However, no reports have addressed that senescence-accelerated mice served as senescence models.
OBJECTIVE: To investigate the differences of neural stem cells proliferation between normal senescence and senescence-accelerated mouse in hippocampus, olfactory bulb and cortex.
METHODS: The hippocampus, olfactory bulb and cortex were obtained from 6 senescence-accelerated mice (senescence-accelerated mouse prone 8) and 6 normal senescence mice (senescence-accelerated mouse/resistance 1). Following frozen section, Ki-67/Nestin immunofluorescence double labeling methods were used to detect the proliferation of neural stem cells in hippocampus, olfactory bulb and cortex. Pictures of immunofluorescence double labeling were taken through Leica Qwin v3 under a fluorescence microscope. Using 40× object lens and 10× eyelens, five consecutive visual fields were selected from each section, and image analysis was conducted using Image-pro-Plus software.
RESULTS AND CONCLUSION: The proliferation of neural stem cells could be found both in normal senescence and senescence-accelerated mice, but there were differences, mainly in the hippocampus and olfactory bulb (P < 0.05). Results indicated that senescence-accelerated might result in low ability of neural stem cells proliferation in hippocampus and olfactory bulb.