The Effect Of Transient Cerebral Ischemia On Hippocampal Neurogenesis And The Expression Of Cystatin C In Mice

Objective To investigate the transient cerebral effect of ischemia on hippocampal neurogenesis and the expression of Cysatin C by an established ischemic mouse model.Methods Twenty-five male C57BL/6 mice(6~8 weeks)were randomly divided into cerebral ischemia group(n = 20)and sham operation group(n = 5).The ischemic model was set up by bilateral carotid arteries occlusion.At 3 d,1 week,2and 4 weeks after ischemia,the hippocampal morphological change was observed by HE staining;the proteins expression of caspase 3,nestin,GFAP and oligodendrocyte specific protein(OSP)were examined by immunohistofluorescence staining;the activation of hippocampal neurogenesis was observed by EdU staining.At 3 d,1week and 2 weeks after ischemia,the protein expression of Cystatin C in different cell types was examined by immunohistofluorescence staining.Results The number of neurons was decreased in hippocampal CA1 region at 1week after ischemia,also the caspase 3 positive cells number was increased at the same time.The EdU positive cells number were increased at 3 d and peaked at 1 week in DG region after ischemia,it increased at 1 week in CA1 region.The nestin,GFAP and OSP positive cells number was increased at 3 d,peaked at 1 week and decreased at 2 weeks in DG region after ischemia.The GFAP and OSP positive cells number were increased at 3 d,peaked at 1 week and decreased at 2 weeks in CA1 region(P<0.05).The Cystatin C positive cells number was increased at 3 d,peaked at 1 week and decreased at 2 weeks in DG region after ischemia.The Cystatin C positive cells number were increased at 3 d,peaked at 1 week and decreased at 2 weeks in CA1region(P <0.05).Conlusion Cerebral ischemia actives the hippocampal DG neurogenesis and promote neural stem cells differentiate into neurons,astrocytes,oligodendrocytes.Cerebral ischemia actives the expression of Cystatin C in the hippocampal DG and CA1.