Objective:To observe the effects of hyperbaric oxygen (HBO) at different courses of treatment on the proliferation of endogenous neural stem cells(NSCs) in cerebral ventricular subventricular zone (SVZ) and hippocampal dentate gyrus (DG) in rats with focal cerebral ischemia at different periods.Methods:The model of focal cerebral ischemia-reperfusion was performed by middle cerebral artery occlusion (MCAO). A total of 105 rats were divided by lottery into pseudo-surgery group(SS), ischemia-reperfusion group (IR group), HBO at 1 st day after ischemia-reperfusion group (IR1d+ HBO group), HBO at 7 th day after ischemia-reperfusion group (IR7d+ HBO group), HBO at 14 th day after ischemia-reperfusion group (IR14d+ HBO group), and HBO at 28 th day after ischemia-reperfusion group (IR28d+ HBO). The SVZ and DG-derived NSCs were detected by immunofluorescence BrdU/Nestin double labeling at the 2 nd, 4 th, 6 th, and 8 th week after modeling. Results:At the 2 nd week after modeling, the number of DG BrdU/Nestin positive cells was 21.20±2.58 in the SS group, 56.40±4.51 in the IR group, 82.80±7.19 in the IR1d+ HBO group, and 70.00±5.09 in the IR7d+ HBO group. At the 4 th week, it was 21.00±2.92 in the SS group, 37.20±3.27 in the IR group, 70.60±5.12 in the IR1d+ HBO group, 57.20±3.56 in the IR7d+ HBO group, 45.80±4.32 in the IR14d+ HBO group. At the 6 th week, it was 20.20±1.92 in the SS group, 26.40±2.74 in the IR group, 48.00±3.16 in the IR1d+ HBO group, 40.60±3.36 in the IR7d+ HBO group, 31.60±2.41 in the IR14d+ HBO group, 26.60±2.30 in the IR28d+ HBO group. The number of DG BrdU/Nestin positive cells was statistically significant among all subgroups during the same period ( P<0.01) except for that at the 8 th week. The pairwise comparison showed the numbers of DG BrdU/Nestin positive cells in the IR group at all time points were all higher than those in the SS group at the same time point ( P<0.05). Except for that at the 8 th week, all the numbers of DG BrdU/Nestin positive cells in the IR1d+ HBO group, the IR7d+ HBO group, and the IR14d+ HBO group at each time point were higher than those in the IR group ( P<0.05). In all the subgroups, the number of DG BrdU/Nestin positive cells reached the highest point at the 2 nd week/the initial measurement point ( P<0.05). At the 2 nd week after modeling, the number of SVZ BrdU/Nestin positive cells was 25.20±2.86 in the SS group, 66.40±2.96 in the IR group, 90.40±6.50 in the IR1d+ HBO group, 75.00±4.58 in the IR7d+ HBO group. At the 4 th week, it was 24.20±1.48 in the SS group, 49.80±4.32 in the IR group, 72.40±4.92 in the IR1d+ HBO group, 57.80±6.46 in the IR7d+ HBO group, 43.80±3.56 in the IR14d+ HBO group. At the 6 th week, it was 24.40±2.41 in the SS group, 28.80±2.77 in the IR group, 51.00±4.30 in the IR1d+ HBO group, 42.00±3.39 in the IR7d+ HBO group, 34.80±2.58 in the IR14d+ HBO group, 31.30±3.41 in the IR28d+ HBO group. The number of SVZ BrdU/Nestin positive cells was statistically significant among all subgroups during the same period ( P<0.05). The pairwise comparison showed the numbers of SVZ BrdU/Nestin positive cells in the IR group at all time points were all higher than those in the SS group at the same time point ( P<0.05) except for the 8 th week. The numbers of SVZ BrdU/Nestin positive cells in the IR1d+ HBO group at each time point were higher than that in the IR group( P<0.05). The numbers of SVZ BrdU/Nestin positive cells in the IR7d+ HBO group, the IR14d+ HBO group, and the IR28d+ HBO group at the 2 nd, 4 th, and 6 th week were higher than those in the IR group at the same time point ( P<0.05). In all the subgroups, the number of SVZ BrdU/Nestin positive cells reached the highest point at the 2 nd week/the initial measurement point ( P<0.05). Conclusion:The earlier HBO treatment on cerebral infarction starts, the better promotion of the proliferation of SVZ and DG-derived NSCs achieves. HBO treatment has almost no effect on the proliferation of endogenous NSCs at late cerebral infarction.

Objective:To observe the differentiation of endogenous neural stem cells (NSCs) in the ischemic brain of rats with focal cerebral ischemia at different stages with various treatments.Methods:The model of focal cerebral ischemia was established by middle cerebral artery occlusion (MCAO). A total of 105 rats were randomly divided into sham-surgery group (SS), ischemia-reperfusion group (IR), receiving hyperbaric oxygen (HBO) 1 day after modeling group (IR1d+ HBO), receiving HBO 7 days after modeling group (IR7d+ HBO group), receiving HBO 14 days after modeling group (IR14d+ HBO group), and receiving HBO 28 days after modeling group (IR28d+ HBO group). At the 2nd, 4th, 6th and 8th week after modeling, the cells of newly generated neurons and astrocyte in the ischemic area were positive in both immunofluorescence BrdU/β-tubulin and BrdU/glial fibrillary acidic protein (GFAP) test were detected.Results:Two weeks after modeling, the expressions of BrdU/β-tubulin were 11.40±1.52 in the SS group, 36.60±2.51 in the IR group, 48.60±3.21 in the IR1d+ HBO group, and 42.60±2.30 in the IR7d+ HBO group; four weeks after modeling, it was 12.20±1.92 in the SS group, 26.20±2.28 in the IR group, 39.80±2.17 in the IR1d+ HBO group, 33.20±1.92 in the IR7d+ HBO group, 29.20±1.48 in the IR14d+ HBO group. Six weeks after modeling, it was 12.40±1.67 in the SS group, 18.60±1.82 in the IR group, 30.20±2.49 in the IR1d+ HBO Group, 25.40±2.79 in the IR7d+ HBO group, 21.40±2.50 in the IR14d+ HBO group, 19.60±1.67 in the IR28d+ HBO group. Eight weeks after modeling, it was 11.80±1.64 in the SS group, 16.40±2.07 in the IR group, 24.40±1.95 in the IR1d+ HBO group, 21.20±1.48 in the IR7d+ HBO group, 18.40±1.67 in the IR14d+ HBO group, and 15.60±1.82 in the IR28d+ HBO group. The differences in the expressions of BrdU/β-tubulin between these groups were statistically significant ( P<0.01). Compared with the SS group, the expression of BrdU/β-tubulin increased in the IR group at each time point ( P<0.05). The expressions of BrdU/β-tubulin in the IR1d+ HBO and the IR7d+ HBO were higher than those in the IR group at each time point; while there were statistical differences comparing those in the IR14d+ HBO group and the IR28d+ HBO group with those in the IR group at each time point ( P>0.05). The expressions of BrdU/β-tubulin were at the highest level at the second week in all the groups except the SS group ( P<0.05). (2) Two weeks after modeling, the expression of BrdU/GFAP was 22.60±1.82 in the SS group, 59.00±3.67 in the IR group, 50.60±2.51 in the IR1d+ HBO group, and 55.20±2.58 in the IR7d+ HBO group. Four weeks after modeling, it was 22.20±1.48 in the SS group, 45.00±2.24 in the IR group, 35.80±1.64 in the IR1d+ HBO group, 40.20±2.16 in the IR7d+ HBO group, and 44.60±2.51 in the IR14d+ HBO group. Six weeks after modeling, it was 22.80±1.64 in the SS group, 26.68±1.78 in the IR group, 27.40±1.67 in the IR1d+ HBO group, 28.40±1.51 in the IR7d+ HBO group, 26.20±1.78 in the IR14d+ HBO group, and 26.20±1.48 in the IR28d+ HBO group. Eight weeks after modeling, it was 21.60±1.81 in the SS group, 21.40±1.14 in the IR group, 24.00±1.58 in the IR1d+ HBO group, 24.80±1.92 in the IR7d+ HBO group, 23.40±1.67 in the IR14d+ HBO group, and 22.20±1.30 in the IR28d+ HBO group. At each time point, the differences of BrdU/GFAP expression between each group were statistically significant ( P<0.05). Furthermore, the BrdU/GFAP expression in the IR group was higher than that in the SS group at each time point except the 8th week. The expressions of BrdU/GFAP in the IR1d+ HBO group and the IR7d+ HBO group were higher than those in the IR group at the 2nd and the 4th weeks ( P<0.05). There was no statistically significant difference in the expressions of BrdU/GFAP between the IR1d+ HBO group and the IR7d+ HBO group at the 6th and the 8th week( P>0.05). There was no statistically significance comparing the expressions of BrdU/GFAP in the IR14d+ HBO and the IR 28d+ HBO group respectively with those in the SS group( P>0.05) at each time point. All the expressions of BrdU/GFAP in each group reached the highest level at the 2nd week ( P<0.05). Conclusion:In the early and the recovery period, HBO can promote the differentiation of NSCs in the ischemic areas into neurons and inhibit its differentiation into astrocytes. An early long-term treatment of HBO can maintain NSCs differentiation in the ischemic area into neurons for a long time.

Objective:To observe the differentiation of endogenous neural stem cells (NSCs) in the ischemic brain of rats with focal cerebral ischemia at different stages with various treatments.Methods:The model of focal cerebral ischemia was established by middle cerebral artery occlusion (MCAO). A total of 105 rats were randomly divided into sham-surgery group (SS), ischemia-reperfusion group (IR), receiving hyperbaric oxygen (HBO) 1 day after modeling group (IR1d+ HBO), receiving HBO 7 days after modeling group (IR7d+ HBO group), receiving HBO 14 days after modeling group (IR14d+ HBO group), and receiving HBO 28 days after modeling group (IR28d+ HBO group). At the 2nd, 4th, 6th and 8th week after modeling, the cells of newly generated neurons and astrocyte in the ischemic area were positive in both immunofluorescence BrdU/β-tubulin and BrdU/glial fibrillary acidic protein (GFAP) test were detected.Results:Two weeks after modeling, the expressions of BrdU/β-tubulin were 11.40±1.52 in the SS group, 36.60±2.51 in the IR group, 48.60±3.21 in the IR1d+ HBO group, and 42.60±2.30 in the IR7d+ HBO group; four weeks after modeling, it was 12.20±1.92 in the SS group, 26.20±2.28 in the IR group, 39.80±2.17 in the IR1d+ HBO group, 33.20±1.92 in the IR7d+ HBO group, 29.20±1.48 in the IR14d+ HBO group. Six weeks after modeling, it was 12.40±1.67 in the SS group, 18.60±1.82 in the IR group, 30.20±2.49 in the IR1d+ HBO Group, 25.40±2.79 in the IR7d+ HBO group, 21.40±2.50 in the IR14d+ HBO group, 19.60±1.67 in the IR28d+ HBO group. Eight weeks after modeling, it was 11.80±1.64 in the SS group, 16.40±2.07 in the IR group, 24.40±1.95 in the IR1d+ HBO group, 21.20±1.48 in the IR7d+ HBO group, 18.40±1.67 in the IR14d+ HBO group, and 15.60±1.82 in the IR28d+ HBO group. The differences in the expressions of BrdU/β-tubulin between these groups were statistically significant ( P<0.01). Compared with the SS group, the expression of BrdU/β-tubulin increased in the IR group at each time point ( P<0.05). The expressions of BrdU/β-tubulin in the IR1d+ HBO and the IR7d+ HBO were higher than those in the IR group at each time point; while there were statistical differences comparing those in the IR14d+ HBO group and the IR28d+ HBO group with those in the IR group at each time point ( P>0.05). The expressions of BrdU/β-tubulin were at the highest level at the second week in all the groups except the SS group ( P<0.05). (2) Two weeks after modeling, the expression of BrdU/GFAP was 22.60±1.82 in the SS group, 59.00±3.67 in the IR group, 50.60±2.51 in the IR1d+ HBO group, and 55.20±2.58 in the IR7d+ HBO group. Four weeks after modeling, it was 22.20±1.48 in the SS group, 45.00±2.24 in the IR group, 35.80±1.64 in the IR1d+ HBO group, 40.20±2.16 in the IR7d+ HBO group, and 44.60±2.51 in the IR14d+ HBO group. Six weeks after modeling, it was 22.80±1.64 in the SS group, 26.68±1.78 in the IR group, 27.40±1.67 in the IR1d+ HBO group, 28.40±1.51 in the IR7d+ HBO group, 26.20±1.78 in the IR14d+ HBO group, and 26.20±1.48 in the IR28d+ HBO group. Eight weeks after modeling, it was 21.60±1.81 in the SS group, 21.40±1.14 in the IR group, 24.00±1.58 in the IR1d+ HBO group, 24.80±1.92 in the IR7d+ HBO group, 23.40±1.67 in the IR14d+ HBO group, and 22.20±1.30 in the IR28d+ HBO group. At each time point, the differences of BrdU/GFAP expression between each group were statistically significant ( P<0.05). Furthermore, the BrdU/GFAP expression in the IR group was higher than that in the SS group at each time point except the 8th week. The expressions of BrdU/GFAP in the IR1d+ HBO group and the IR7d+ HBO group were higher than those in the IR group at the 2nd and the 4th weeks ( P<0.05). There was no statistically significant difference in the expressions of BrdU/GFAP between the IR1d+ HBO group and the IR7d+ HBO group at the 6th and the 8th week( P>0.05). There was no statistically significance comparing the expressions of BrdU/GFAP in the IR14d+ HBO and the IR 28d+ HBO group respectively with those in the SS group( P>0.05) at each time point. All the expressions of BrdU/GFAP in each group reached the highest level at the 2nd week ( P<0.05). Conclusion:In the early and the recovery period, HBO can promote the differentiation of NSCs in the ischemic areas into neurons and inhibit its differentiation into astrocytes. An early long-term treatment of HBO can maintain NSCs differentiation in the ischemic area into neurons for a long time.

Objective:To observe the effects of hyperbaric oxygen (HBO) at different courses of treatment on the proliferation of endogenous neural stem cells(NSCs) in cerebral ventricular subventricular zone (SVZ) and hippocampal dentate gyrus (DG) in rats with focal cerebral ischemia at different periods.Methods:The model of focal cerebral ischemia-reperfusion was performed by middle cerebral artery occlusion (MCAO). A total of 105 rats were divided by lottery into pseudo-surgery group(SS), ischemia-reperfusion group (IR group), HBO at 1 st day after ischemia-reperfusion group (IR1d+ HBO group), HBO at 7 th day after ischemia-reperfusion group (IR7d+ HBO group), HBO at 14 th day after ischemia-reperfusion group (IR14d+ HBO group), and HBO at 28 th day after ischemia-reperfusion group (IR28d+ HBO). The SVZ and DG-derived NSCs were detected by immunofluorescence BrdU/Nestin double labeling at the 2 nd, 4 th, 6 th, and 8 th week after modeling. Results:At the 2 nd week after modeling, the number of DG BrdU/Nestin positive cells was 21.20±2.58 in the SS group, 56.40±4.51 in the IR group, 82.80±7.19 in the IR1d+ HBO group, and 70.00±5.09 in the IR7d+ HBO group. At the 4 th week, it was 21.00±2.92 in the SS group, 37.20±3.27 in the IR group, 70.60±5.12 in the IR1d+ HBO group, 57.20±3.56 in the IR7d+ HBO group, 45.80±4.32 in the IR14d+ HBO group. At the 6 th week, it was 20.20±1.92 in the SS group, 26.40±2.74 in the IR group, 48.00±3.16 in the IR1d+ HBO group, 40.60±3.36 in the IR7d+ HBO group, 31.60±2.41 in the IR14d+ HBO group, 26.60±2.30 in the IR28d+ HBO group. The number of DG BrdU/Nestin positive cells was statistically significant among all subgroups during the same period ( P<0.01) except for that at the 8 th week. The pairwise comparison showed the numbers of DG BrdU/Nestin positive cells in the IR group at all time points were all higher than those in the SS group at the same time point ( P<0.05). Except for that at the 8 th week, all the numbers of DG BrdU/Nestin positive cells in the IR1d+ HBO group, the IR7d+ HBO group, and the IR14d+ HBO group at each time point were higher than those in the IR group ( P<0.05). In all the subgroups, the number of DG BrdU/Nestin positive cells reached the highest point at the 2 nd week/the initial measurement point ( P<0.05). At the 2 nd week after modeling, the number of SVZ BrdU/Nestin positive cells was 25.20±2.86 in the SS group, 66.40±2.96 in the IR group, 90.40±6.50 in the IR1d+ HBO group, 75.00±4.58 in the IR7d+ HBO group. At the 4 th week, it was 24.20±1.48 in the SS group, 49.80±4.32 in the IR group, 72.40±4.92 in the IR1d+ HBO group, 57.80±6.46 in the IR7d+ HBO group, 43.80±3.56 in the IR14d+ HBO group. At the 6 th week, it was 24.40±2.41 in the SS group, 28.80±2.77 in the IR group, 51.00±4.30 in the IR1d+ HBO group, 42.00±3.39 in the IR7d+ HBO group, 34.80±2.58 in the IR14d+ HBO group, 31.30±3.41 in the IR28d+ HBO group. The number of SVZ BrdU/Nestin positive cells was statistically significant among all subgroups during the same period ( P<0.05). The pairwise comparison showed the numbers of SVZ BrdU/Nestin positive cells in the IR group at all time points were all higher than those in the SS group at the same time point ( P<0.05) except for the 8 th week. The numbers of SVZ BrdU/Nestin positive cells in the IR1d+ HBO group at each time point were higher than that in the IR group( P<0.05). The numbers of SVZ BrdU/Nestin positive cells in the IR7d+ HBO group, the IR14d+ HBO group, and the IR28d+ HBO group at the 2 nd, 4 th, and 6 th week were higher than those in the IR group at the same time point ( P<0.05). In all the subgroups, the number of SVZ BrdU/Nestin positive cells reached the highest point at the 2 nd week/the initial measurement point ( P<0.05). Conclusion:The earlier HBO treatment on cerebral infarction starts, the better promotion of the proliferation of SVZ and DG-derived NSCs achieves. HBO treatment has almost no effect on the proliferation of endogenous NSCs at late cerebral infarction.