Mitochondria play an important role in neuronal apoptosis caused by cerebral ischemia, and the role is mediated by the expression of mitochondrial proteins. This study investigated the involvement of mitochondrial pro...Mitochondria play an important role in neuronal apoptosis caused by cerebral ischemia, and the role is mediated by the expression of mitochondrial proteins. This study investigated the involvement of mitochondrial proteins in hippocampal cell apoptosis after transient cerebral ischemia-reperfusion injury in aged rats using a comparative proteomics strategy. Our exper-imental results show that the aged rat brain is sensitive to ischemia-reperfusion injury and that transient ischemia led to cell apoptosis in the hippocampus and changes in memory and cognition of aged rats. Differential proteomics analysis suggested that this phenomenon may be mediated by mitochondrial proteins associated with energy metabolism and apoptosis in aged rats. This study provides potential drug targets for the treatment of transient cerebral isch-emia-reperfusion injury.展开更多
BACKGROUND: Previous studies of cerebral ischemia have used young animals, with an ischemic time greater than 5 minutes (safe time limit). Despite an increased understanding of neuronal apoptosis, it remains uncert...BACKGROUND: Previous studies of cerebral ischemia have used young animals, with an ischemic time greater than 5 minutes (safe time limit). Despite an increased understanding of neuronal apoptosis, it remains uncertain whether brief cerebral ischemic events of 5 minutes or less damage brain tissue in elderly rodents. OBJECTIVE: To investigate the effects of transient cerebral ischemia (5 minutes)/reperfusion injury on brain cortical and hippocampal edema, aquaporin-4 (AQP-4) expression, and neuronal apoptosis in aged rats, and to compare ischemic sensitivity between cortex and hippocampus. DESIGN, TIME AND SETTING: A randomized, controlled, animal experiment was performed at the Institute of Cerebrovascular Disease, Qingdao University Medical School from April 2008 to March 2009. MATERIALS: Rabbit anti-AQP-4 polyclonal antibody, TUNEL kit, and SABC immunohistochemistry kit were purchased from Wuhan Boster Bioengineering, China. METHODS: A total of 160 healthy, male, aged 19-21 months, Wistar rats were randomly assigned to 4 groups: sham-surgery, and ischemia 1-, 3-, and 5-minute groups, with 40 rats in each group. The global cerebral ischemia model was established using the Pusinelli four-vessel occlusion, and the three cerebral ischemia groups were subdivided into reperfusion 12-hour, 1-, 2-, 3-, and 7-day subgroups, with 8 rats in each subgroup. The sham-surgery group was subjected to exposure of the first cervical bilateral alar foramina and bilateral common carotid arteries. MAIN OUTCOME MEASURES: The dry-wet weight assay was used to measure brain water content and histopathology of the cortex and hippocampus was observed following hematoxylin-eosin staining. In addition, cortical and hippocampal AQP-4 expression was detected by streptavidin-biotin complex immunohistochemistry, and neuronal apoptosis was detected by the TUNEL method. RESULTS: There was no significant difference in brain water content or AQP-4 expression in the cortex and hippocampus between ischemia 1- and 3-minute groups and the sham-surgery group or brain water content or AQP-4 expression in the cortex between ischemia 5-minute group and sham-surgery group (P 〉 0.05). However, brain water content and AQP-4 expression in the hippocampus after 5 minutes of cerebral ischemia were significantly increased compared with the sham-surgery group (P 〈 0.05 or P 〈 0.01). Several TUNEL-positive cells were observed in the cortex and hippocampus of the sham-surgery group and ischemia 1-minute group, as well as in the cortex of the ischemia 3-minute group. In addition, the number of apoptotic neurons in the hippocampus of ischemia 3-minute group and in the cortex and hippocampus of ischemia 5-minute group was significantly increased (P 〈 0.05 or P 〈 0.01 ). Neuronal apoptosis was increased after 12 hours of ischemia/reperfusion, and it reached a peak by 2 days (P 〈 0.01). CONCLUSION: Transient cerebral ischemia (5 minutes) resulted in increased hippocampal edema, AQP-4 expression, and neuronal apoptosis. Moreover, cerebral ischemia had a greater effect on neuronal apoptosis than brain edema or AQP-4 expression, and the hippocampus was more sensitive than the cortex.展开更多
BACKGROUND: It has been demonstrated that adenosine can induce glial cell to release cytochrome C, enhance expression of apoptotic gene bax, inhibit anti-apoptotic gene bcl-2, and activate caspase-3 to apoptosis; Wher...BACKGROUND: It has been demonstrated that adenosine can induce glial cell to release cytochrome C, enhance expression of apoptotic gene bax, inhibit anti-apoptotic gene bcl-2, and activate caspase-3 to apoptosis; Whereas inosine can inhibit neuronal apoptosis which is similar to bcl-2. OBJECTIVE: To observe the effects of inosine on neuronal apoptosis and expression of cytochrome C mRNA in rats after focal cerebral ischemia/reperfusion, and analyze the pathway of its neuroprotective effect. DESIGN: A randomised controlled animal trial. SETTINGS: Department of Neurology, Rongcheng Second People's Hospital; Department of Neurology, Affiliated Union Hospital, Tongji Medical College, Huazhong University of Science and Technology. MATERIALS: Sixty-eight rats, weighing 230-280 g and clean grade, were used. TdT-mediated dUTP-biotin nick end labeling (TUNEL) and cytochrome C mRNA in situ hybridization kits and DAB staining kit were purchased from Wuhan Boster Biological Co., Ltd.; Inosine injection [200 mg (2 mL) each] from Qingdao First Pharmaceutical Factory. METHODS: The experiment was accomplished in the animal experimental center in Tongji Medical College of Huazhong University of Science and Technology from December 2003 to June 2005. ① Sixty-four rats were made into focal ischemia by middle cerebral artery occlusion (MCAO) with a nylon monofilament suture. The successfully induced rats were assigned to inosine group (n =32) and model group (n =32) at random. Rats in the inosine group were intraperitoneally administrated with inosine in dose of 100 mg/kg preoperatively, twice a day, 7 days in all. The rats in the control group were injected with the same dose of saline solution by the similar way preoperatively. Each group was randomized into ischemia /reperfusion 2, 6, 12, 24 hours, 2, 3, 7 and 14 days subgroups consisted of 4 rats. The other 4 rats were taken as the sham-operated group, the rats were given the same treatment except for not introduced the filament into the external carotid artery stump, and brain tissue was removed at 2 hours of reperfusion. ② In situ hybridization was performed to examine the expression of cytochrome C mRNA while TUNEL staining was made to characterize apoptosis. ③ The t test was used to compare the difference of measurement data. MAIN OUTCOME MEASURES: ① Neuronal apoptosis in the different regions of the ischemic brain tissue; ② Expression of cytochrome C mRNA in the different regions at different time points after MCAO. RESULTS: All the 68 rats were involved in the analysis of results. ① Neuronal apoptosis: A small number of TUNEL-positive cells were detected in the sham-operated brain and non-ischemic brain. The number of apoptotic cells in the ischemic cortex peaked at 24 hours of reperfusion [(72.00±1.98) cells] and that in the striatum peaked at 2 days [(94.75±3.57) cells], then decreased to the level of sham-operated group at 14 days. Inosine could reduce apoptotic cells from 12 hours to 7 days of reperfusion as compared with the model group (t =6.19-26.67, P < 0.01). ② Cytochrome C mRNA expression: There was weak expression of cytochrome C mRNA in both sham-operated brain and contralateral brain. Cytochrome C was detected at 2 hours of reperfusion in ischemic brain [(25.75±3.50), (39.75±2.49) cells], and strongly increased to a peak at 12 hours and 24 hours of reperfusion in cortex and striatum [(122.50±6.69), (119.25±5.12) cells], respectively. Furthermore, inosine could significantly decrease cytochrome C expression in cortex at 12 hours to 14 days of reperfusion after ischemic reperfusion and that in striatum at 12 hours to 3 days (t =8.67-43.26, P < 0.01). CONCLUSION: Inosine can exert a neuroprotective effect by inhibiting apoptosis and cytochrome C mRNA expression.展开更多
Studies have shown that Picroside Ⅱ attenuates inflammatory reactions following brain ischemia through the inhibition of the TLR-4-NF-KB signal transduction pathway, and ameliorates cerebral edema through the reducti...Studies have shown that Picroside Ⅱ attenuates inflammatory reactions following brain ischemia through the inhibition of the TLR-4-NF-KB signal transduction pathway, and ameliorates cerebral edema through the reduction of aquaporin-4 expression. Matrix metalloproteinase-9 (MMP-9), located downstream of the TLR-4-NF-KB signal transduction pathway, can degrade the neurovascular matrix, damage the blood-brain barrier to induce cerebral edema, and directly result in neuronal apoptosis and brain injury, Therefore, the present study further observed MMP-9 expression in the brain tissues of rats with cerebral ischemia/reperfusion injury following Picroside Ⅱ treatment. Results demonstrated that Picroside Ⅱ significantly reduced MMP-9 expression in ischemic brain tissues, as well as neuronal apoptosis and brain infarct volume, suggesting Picroside Ⅱ exhibits neuroprotection by down-regulating MMP-9 expression and inhibiting cell apoptosis.展开更多
Genistein is one of several isoflavones that has a structure similar to 17β-estradiol, has a strong antioxidant effect, and a high affinity to estrogen receptors. At 15 weeks after ovariectomy, the expression of Bcl-...Genistein is one of several isoflavones that has a structure similar to 17β-estradiol, has a strong antioxidant effect, and a high affinity to estrogen receptors. At 15 weeks after ovariectomy, the expression of Bcl-2 in the hippocampus of rats decreased and Bax expression increased, with an obvious upregulation of apoptosis. However, intraperitoneal injection of genistein or 17β-estradiol for 15 consecutive weeks from the second day after operation upregulated Bcl-2 protein expression downregulated Bax protein expression, and attenuated hippocampal neuron apoptosis. Our experimental findings indicate that long-term intervention with genistein can lead to a decrease in apoptosis in hippocampal neurons following ovadectomy, upregulate the expression of Bcl-2, and downregulate the expression of Bax. In addition, genistein and 17β-estradiol play equal anti-apoptotic and neuroprotective roles.展开更多
Objective:To investigate the synergistic effect of Naoxintong Capsule(NXTC,脑心通胶囊)and Guhong Injection(GHI,谷红注射液)on cerebral ischemia-reperfusion(丨/R)injury.Methods:Forty-eight Sprague-Dawley rats were divid...Objective:To investigate the synergistic effect of Naoxintong Capsule(NXTC,脑心通胶囊)and Guhong Injection(GHI,谷红注射液)on cerebral ischemia-reperfusion(丨/R)injury.Methods:Forty-eight Sprague-Dawley rats were divided into 6 groups:control group,oxygen and glucose deprivation(OGD)group,nimodipine group(9.375 mg/kg),NXTC group(0.5 g/kg),GHI group(5 mL/kg)and NXTC+GHI group(0.5 g/kg NXTC+5 mL/kg GHI),after the onset of reperfusion and once per day for the following 7 days.Blood was collected 1 h after final administration,and the sera were collected.Cultured primary rat brain microvascular endothelial cells(rBMECs)were subjected to OGD to establish a cell injury model.Untreated rBMECs were used as blank control.The cell counting kit-8 assay was used to assess cell viability using the sera.Malondialdehyde(MDA)and superoxide dismutase(SOD)levels were assessed using an enzyme-linked immunosorbent assay.Apoptosis was evaluated after Hoechst33342 staining using fluorescence microscopy and flow cytometry.JC-1 staining was performed to assess changes in mitochondrial membrane potential.Results:Statistical analysis indicated that more than 95%of the cells were rBMECs.Compared with the OGD group,the cellular morphology of the all drug delivery groups improved.In particular,the combined drug group had the most significant effect.Compared with the OGD group,all drug intervention groups induced a decrease in the apoptotic rate of rBMECs,increased the SOD levels,and decreased the MDA levels(all P<0.01).Compared with the mono-therapy groups,the NXTC+GHI group exhibited a significant improvement in the number of apoptotic rBMECs(P<0.01).All drug intervention groups showed different degrees of increase in membrane potential,and the NXTC+GHI group was higher than the NXTC or GHI group(P<0.01).Conclusion:The combinationa application of NXTC and GHI on cerebral l/R injury clearly resulted in protective benefits.展开更多
基金supported by a grant from Ministry of Science and Technology of Qingdao City,No.10-3-4-7-8-JCH
文摘Mitochondria play an important role in neuronal apoptosis caused by cerebral ischemia, and the role is mediated by the expression of mitochondrial proteins. This study investigated the involvement of mitochondrial proteins in hippocampal cell apoptosis after transient cerebral ischemia-reperfusion injury in aged rats using a comparative proteomics strategy. Our exper-imental results show that the aged rat brain is sensitive to ischemia-reperfusion injury and that transient ischemia led to cell apoptosis in the hippocampus and changes in memory and cognition of aged rats. Differential proteomics analysis suggested that this phenomenon may be mediated by mitochondrial proteins associated with energy metabolism and apoptosis in aged rats. This study provides potential drug targets for the treatment of transient cerebral isch-emia-reperfusion injury.
基金Supported by: the Foundation Program of Shandong Heatth Department, No. 2001CAICKAF
文摘BACKGROUND: Previous studies of cerebral ischemia have used young animals, with an ischemic time greater than 5 minutes (safe time limit). Despite an increased understanding of neuronal apoptosis, it remains uncertain whether brief cerebral ischemic events of 5 minutes or less damage brain tissue in elderly rodents. OBJECTIVE: To investigate the effects of transient cerebral ischemia (5 minutes)/reperfusion injury on brain cortical and hippocampal edema, aquaporin-4 (AQP-4) expression, and neuronal apoptosis in aged rats, and to compare ischemic sensitivity between cortex and hippocampus. DESIGN, TIME AND SETTING: A randomized, controlled, animal experiment was performed at the Institute of Cerebrovascular Disease, Qingdao University Medical School from April 2008 to March 2009. MATERIALS: Rabbit anti-AQP-4 polyclonal antibody, TUNEL kit, and SABC immunohistochemistry kit were purchased from Wuhan Boster Bioengineering, China. METHODS: A total of 160 healthy, male, aged 19-21 months, Wistar rats were randomly assigned to 4 groups: sham-surgery, and ischemia 1-, 3-, and 5-minute groups, with 40 rats in each group. The global cerebral ischemia model was established using the Pusinelli four-vessel occlusion, and the three cerebral ischemia groups were subdivided into reperfusion 12-hour, 1-, 2-, 3-, and 7-day subgroups, with 8 rats in each subgroup. The sham-surgery group was subjected to exposure of the first cervical bilateral alar foramina and bilateral common carotid arteries. MAIN OUTCOME MEASURES: The dry-wet weight assay was used to measure brain water content and histopathology of the cortex and hippocampus was observed following hematoxylin-eosin staining. In addition, cortical and hippocampal AQP-4 expression was detected by streptavidin-biotin complex immunohistochemistry, and neuronal apoptosis was detected by the TUNEL method. RESULTS: There was no significant difference in brain water content or AQP-4 expression in the cortex and hippocampus between ischemia 1- and 3-minute groups and the sham-surgery group or brain water content or AQP-4 expression in the cortex between ischemia 5-minute group and sham-surgery group (P 〉 0.05). However, brain water content and AQP-4 expression in the hippocampus after 5 minutes of cerebral ischemia were significantly increased compared with the sham-surgery group (P 〈 0.05 or P 〈 0.01). Several TUNEL-positive cells were observed in the cortex and hippocampus of the sham-surgery group and ischemia 1-minute group, as well as in the cortex of the ischemia 3-minute group. In addition, the number of apoptotic neurons in the hippocampus of ischemia 3-minute group and in the cortex and hippocampus of ischemia 5-minute group was significantly increased (P 〈 0.05 or P 〈 0.01 ). Neuronal apoptosis was increased after 12 hours of ischemia/reperfusion, and it reached a peak by 2 days (P 〈 0.01). CONCLUSION: Transient cerebral ischemia (5 minutes) resulted in increased hippocampal edema, AQP-4 expression, and neuronal apoptosis. Moreover, cerebral ischemia had a greater effect on neuronal apoptosis than brain edema or AQP-4 expression, and the hippocampus was more sensitive than the cortex.
基金the Natural Science Fund of Shandong Province, No.Y2001C04
文摘BACKGROUND: It has been demonstrated that adenosine can induce glial cell to release cytochrome C, enhance expression of apoptotic gene bax, inhibit anti-apoptotic gene bcl-2, and activate caspase-3 to apoptosis; Whereas inosine can inhibit neuronal apoptosis which is similar to bcl-2. OBJECTIVE: To observe the effects of inosine on neuronal apoptosis and expression of cytochrome C mRNA in rats after focal cerebral ischemia/reperfusion, and analyze the pathway of its neuroprotective effect. DESIGN: A randomised controlled animal trial. SETTINGS: Department of Neurology, Rongcheng Second People's Hospital; Department of Neurology, Affiliated Union Hospital, Tongji Medical College, Huazhong University of Science and Technology. MATERIALS: Sixty-eight rats, weighing 230-280 g and clean grade, were used. TdT-mediated dUTP-biotin nick end labeling (TUNEL) and cytochrome C mRNA in situ hybridization kits and DAB staining kit were purchased from Wuhan Boster Biological Co., Ltd.; Inosine injection [200 mg (2 mL) each] from Qingdao First Pharmaceutical Factory. METHODS: The experiment was accomplished in the animal experimental center in Tongji Medical College of Huazhong University of Science and Technology from December 2003 to June 2005. ① Sixty-four rats were made into focal ischemia by middle cerebral artery occlusion (MCAO) with a nylon monofilament suture. The successfully induced rats were assigned to inosine group (n =32) and model group (n =32) at random. Rats in the inosine group were intraperitoneally administrated with inosine in dose of 100 mg/kg preoperatively, twice a day, 7 days in all. The rats in the control group were injected with the same dose of saline solution by the similar way preoperatively. Each group was randomized into ischemia /reperfusion 2, 6, 12, 24 hours, 2, 3, 7 and 14 days subgroups consisted of 4 rats. The other 4 rats were taken as the sham-operated group, the rats were given the same treatment except for not introduced the filament into the external carotid artery stump, and brain tissue was removed at 2 hours of reperfusion. ② In situ hybridization was performed to examine the expression of cytochrome C mRNA while TUNEL staining was made to characterize apoptosis. ③ The t test was used to compare the difference of measurement data. MAIN OUTCOME MEASURES: ① Neuronal apoptosis in the different regions of the ischemic brain tissue; ② Expression of cytochrome C mRNA in the different regions at different time points after MCAO. RESULTS: All the 68 rats were involved in the analysis of results. ① Neuronal apoptosis: A small number of TUNEL-positive cells were detected in the sham-operated brain and non-ischemic brain. The number of apoptotic cells in the ischemic cortex peaked at 24 hours of reperfusion [(72.00±1.98) cells] and that in the striatum peaked at 2 days [(94.75±3.57) cells], then decreased to the level of sham-operated group at 14 days. Inosine could reduce apoptotic cells from 12 hours to 7 days of reperfusion as compared with the model group (t =6.19-26.67, P < 0.01). ② Cytochrome C mRNA expression: There was weak expression of cytochrome C mRNA in both sham-operated brain and contralateral brain. Cytochrome C was detected at 2 hours of reperfusion in ischemic brain [(25.75±3.50), (39.75±2.49) cells], and strongly increased to a peak at 12 hours and 24 hours of reperfusion in cortex and striatum [(122.50±6.69), (119.25±5.12) cells], respectively. Furthermore, inosine could significantly decrease cytochrome C expression in cortex at 12 hours to 14 days of reperfusion after ischemic reperfusion and that in striatum at 12 hours to 3 days (t =8.67-43.26, P < 0.01). CONCLUSION: Inosine can exert a neuroprotective effect by inhibiting apoptosis and cytochrome C mRNA expression.
基金the National Natural Science Foundation of China,No.30873391
文摘Studies have shown that Picroside Ⅱ attenuates inflammatory reactions following brain ischemia through the inhibition of the TLR-4-NF-KB signal transduction pathway, and ameliorates cerebral edema through the reduction of aquaporin-4 expression. Matrix metalloproteinase-9 (MMP-9), located downstream of the TLR-4-NF-KB signal transduction pathway, can degrade the neurovascular matrix, damage the blood-brain barrier to induce cerebral edema, and directly result in neuronal apoptosis and brain injury, Therefore, the present study further observed MMP-9 expression in the brain tissues of rats with cerebral ischemia/reperfusion injury following Picroside Ⅱ treatment. Results demonstrated that Picroside Ⅱ significantly reduced MMP-9 expression in ischemic brain tissues, as well as neuronal apoptosis and brain infarct volume, suggesting Picroside Ⅱ exhibits neuroprotection by down-regulating MMP-9 expression and inhibiting cell apoptosis.
基金supported by Hunan Provincial Traditional Medicine Administration Bureau,No.2010044
文摘Genistein is one of several isoflavones that has a structure similar to 17β-estradiol, has a strong antioxidant effect, and a high affinity to estrogen receptors. At 15 weeks after ovariectomy, the expression of Bcl-2 in the hippocampus of rats decreased and Bax expression increased, with an obvious upregulation of apoptosis. However, intraperitoneal injection of genistein or 17β-estradiol for 15 consecutive weeks from the second day after operation upregulated Bcl-2 protein expression downregulated Bax protein expression, and attenuated hippocampal neuron apoptosis. Our experimental findings indicate that long-term intervention with genistein can lead to a decrease in apoptosis in hippocampal neurons following ovadectomy, upregulate the expression of Bcl-2, and downregulate the expression of Bax. In addition, genistein and 17β-estradiol play equal anti-apoptotic and neuroprotective roles.
基金the National Natural Science Foundation of China(No.81630105,81973560)Zhejiang Provincial Natural Science Foundation of China(Nos.LZ17H270001,LZ18H270001)Zhejiang Provincial Program for the Cultivation of High-level Innovative Health Talents。
文摘Objective:To investigate the synergistic effect of Naoxintong Capsule(NXTC,脑心通胶囊)and Guhong Injection(GHI,谷红注射液)on cerebral ischemia-reperfusion(丨/R)injury.Methods:Forty-eight Sprague-Dawley rats were divided into 6 groups:control group,oxygen and glucose deprivation(OGD)group,nimodipine group(9.375 mg/kg),NXTC group(0.5 g/kg),GHI group(5 mL/kg)and NXTC+GHI group(0.5 g/kg NXTC+5 mL/kg GHI),after the onset of reperfusion and once per day for the following 7 days.Blood was collected 1 h after final administration,and the sera were collected.Cultured primary rat brain microvascular endothelial cells(rBMECs)were subjected to OGD to establish a cell injury model.Untreated rBMECs were used as blank control.The cell counting kit-8 assay was used to assess cell viability using the sera.Malondialdehyde(MDA)and superoxide dismutase(SOD)levels were assessed using an enzyme-linked immunosorbent assay.Apoptosis was evaluated after Hoechst33342 staining using fluorescence microscopy and flow cytometry.JC-1 staining was performed to assess changes in mitochondrial membrane potential.Results:Statistical analysis indicated that more than 95%of the cells were rBMECs.Compared with the OGD group,the cellular morphology of the all drug delivery groups improved.In particular,the combined drug group had the most significant effect.Compared with the OGD group,all drug intervention groups induced a decrease in the apoptotic rate of rBMECs,increased the SOD levels,and decreased the MDA levels(all P<0.01).Compared with the mono-therapy groups,the NXTC+GHI group exhibited a significant improvement in the number of apoptotic rBMECs(P<0.01).All drug intervention groups showed different degrees of increase in membrane potential,and the NXTC+GHI group was higher than the NXTC or GHI group(P<0.01).Conclusion:The combinationa application of NXTC and GHI on cerebral l/R injury clearly resulted in protective benefits.