Ginsenoside Rgl is the major pharmacologically active component of ginseng, and is reported to have various therapeutic actions. To determine whether it induces the differentiation of neural stem cells, and whether ne...Ginsenoside Rgl is the major pharmacologically active component of ginseng, and is reported to have various therapeutic actions. To determine whether it induces the differentiation of neural stem cells, and whether neural stem cell transplantation after induction has therapeutic effects on hypoxic-ischemic encephalopathy, we cultured neural stem cells in 10-80 ~tM ginsenoside Rgl. Immunohistochemistry revealed that of the concentrations tested, 20 mM ginsenoside Rgl had the greatest differentiation-inducing effect and was the concentration used for subsequent exper- iments. Whole-cell patch clamp showed that neural stem cells induced by 20 jaM ginsenoside Rgl were more mature than non-induced cells. We then established neonatal rat models of hypox- ic-ischemic encephalopathy using the suture method, and ginsenoside Rgl-induced neural stem cells were transplanted via intracerebroventricular injection. These tests confirmed that neural stem cells induced by ginsenoside had fewer pathological lesions and had a significantly better behavioral capacity than model rats that received saline. Transplanted neural stem cells expressed neuron-specific enolase, and were mainly distributed in the hippocampus and cerebral cortex. The present data suggest that ginsenoside Rgl-induced neural stem cells can promote the partial recovery of complicated brain functions in models of hypoxic-ischemic encephalopathy.展开更多
Secondary brain damage caused by hyperactivation of autophagy and inflammatory responses in neurons plays an important role in hypoxic-ischemic brain damage(HIBD).Although previous studies have implicated Toll-like re...Secondary brain damage caused by hyperactivation of autophagy and inflammatory responses in neurons plays an important role in hypoxic-ischemic brain damage(HIBD).Although previous studies have implicated Toll-like receptor 4(TLR4)and nuclear factor kappa-B(NF-κB)in the neuroinflammatory response elicited by brain injury,the role and mechanisms of the TLR4-mediated autophagy signaling pathway in neonatal HIBD are still unclear.We hypothesized that this pathway can regulate brain damage by modulating neuron autophagy and neuroinflammation in neonatal rats with HIBD.Hence,we established a neonatal HIBD rat model using the Rice-Vannucci method,and injected 0.75,1.5,or 3 mg/kg of the TLR4 inhibitor resatorvid(TAK-242)30 minutes after hypoxic ischemia.Our results indicate that administering TAK-242 to neonatal rats after HIBD could significantly reduce the infarct volume and the extent of cerebral edema,alleviate neuronal damage and neurobehavioral impairment,and decrease the expression levels of TLR4,phospho-NF-κB p65,Beclin-1,microtubule-associated protein l light chain 3,tumor necrosis factor-α,and interleukin-1βin the hippocampus.Thus,TAK-242 appears to exert a neuroprotective effect after HIBD by inhibiting activation of autophagy and the release of inflammatory cytokines via inhibition of the TLR4/NF-κB signaling pathway.This study was approved by the Laboratory Animal Ethics Committee of Affiliated Hospital of Yangzhou University,China(approval No.20180114-15)on January 14,2018.展开更多
Hyperbaric oxygen therapy for the treatment of neonatal hypoxic-ischemic brain damage has been used clinically for many years, but its effectiveness remains controversial. In addition, the mechanism of this potential ...Hyperbaric oxygen therapy for the treatment of neonatal hypoxic-ischemic brain damage has been used clinically for many years, but its effectiveness remains controversial. In addition, the mechanism of this potential neuroprotective effect remains unclear. This study aimed to investigate the influence of hyperbaric oxygen on the proliferation of neural stem cells in the subventricular zone of neonatal Sprague-Dawley rats （7 days old） subjected to hypoxic-ischemic brain damage. Six hours after modeling, rats were treated with hyperbaric oxygen once daily for 7 days. Immunohistochemistry revealed that the number of 5-bromo-2＇-deoxyuridine positive and nestin positive cells in the subventricular zone of neonatal rats increased at day 3 after hypoxic-ischemic brain damage and peaked at day 5. After hyperbaric oxygen treatment, the number of 5-bromo-2＇- deoxyuddine positive and nestin positive cells began to increase at day 1, and was significantly higher than that in normal rats and model rats until day 21. Hematoxylin-eosin staining showed that hyperbaric oxygen treatment could attenuate pathological changes to brain tissue in neonatal rats, and reduce the number of degenerating and necrotic nerve cells. Our experimental findings indicate that hyperbaric oxygen treatment enhances the proliferation of neural stem cells in the subventricular zone of neonatal rats with hypoxic-ischemic brain damage, and has therapeutic potential for promoting neurological recovery following brain injury.展开更多
目的探讨丰富环境（EE）对缺氧缺血性脑损伤（HIBD）新生大鼠学习记忆能力及海马区脑源性神经生长因子（BDNF）和突触素蛋白表达的影响。方法将40只7日龄Wistar雄性大鼠随机分为6 h EE干预（6 h EE）组、12 h EE干预（12 h EE）组、模...目的探讨丰富环境（EE）对缺氧缺血性脑损伤（HIBD）新生大鼠学习记忆能力及海马区脑源性神经生长因子（BDNF）和突触素蛋白表达的影响。方法将40只7日龄Wistar雄性大鼠随机分为6 h EE干预（6 h EE）组、12 h EE干预（12 h EE）组、模型组和假手术组，每组10只。干预组和模型组均运用Rice法（1981）制备大鼠HIBD模型。干预组分别进行14 d的6 h和12 h的EE干预。运用Morris水迷宫行为学实验检测大鼠的学习记忆能力。Western blot法检测大鼠海马区BDNF、突触素蛋白的表达。结果4组大鼠训练期间的逃避潜伏期随着训练天数的增加逐渐降低，但4组大鼠之间的逃避潜伏期比较差异无统计学意义（F＝0.237，P〉0.05）。6 h EE组、12 h EE组和模型组新生大鼠在目标象限寻找平台的时间均短于假手术组，海马区BDNF和突触素蛋白（6 h EE组：0.529±0.038、0.889±0.027，12 h EE组：0.660±0.034、1.114±0.037，模型组：0.225±0.015、0.672±0.057）的表达相比于假手术组（0.803±0.026、1.347±0.092）也有所下降。与模型组相比，6 h EE组和12 h EE组新生大鼠在目标象限寻找平台的时间更长，并且海马区BDNF和突触素蛋白的表达显著上升。12 h EE组在目标象限寻找平台的时间以及海马区BDNF与突触素蛋白的表达情况都优于6 h EE组。结论EE能够改善HIBD幼鼠的学习记忆能力，保护神经元细胞，其机制可能与上调海马区BDNF和突触素蛋白表达有关。展开更多
Autophagy has been suggested to participate in the pathology of hypoxic-ischemic brain damage（HIBD）.However,its regulatory role in HIBD remains unclear and was thus examined here using a rat model.To induce HIBD,the...Autophagy has been suggested to participate in the pathology of hypoxic-ischemic brain damage（HIBD）.However,its regulatory role in HIBD remains unclear and was thus examined here using a rat model.To induce HIBD,the left common carotid artery was ligated in neonatal rats,and the rats were subjected to hypoxia for 2 hours.Some of these rats were intraperitoneally pretreated with the autophagy inhibitor 3-methyladenine（10 m M in 10 μL） or the autophagy stimulator rapamycin（1 g/kg） 1 hour before artery ligation.Our findings demonstrated that hypoxia-ischemia-induced hippocampal injury in neonatal rats was accompanied by increased expression levels of the autophagy-related proteins light chain 3 and Beclin-1 as well as of the AMPA receptor subunit GluR 1,but by reduced expression of GluR 2.Pretreatment with the autophagy inhibitor 3-methyladenine blocked hypoxia-ischemia-induced hippocampal injury,whereas pretreatment with the autophagy stimulator rapamycin significantly augmented hippocampal injury.Additionally,3-methyladenine pretreatment blocked the hypoxia-ischemia-induced upregulation of Glu R1 and downregulation of GluR2 in the hippocampus.By contrast,rapamycin further elevated hippocampal Glu R1 levels and exacerbated decreased GluR2 expression levels in neonates with HIBD.Our results indicate that autophagy inhibition favors the prevention of HIBD in neonatal rats,at least in part,through normalizing Glu R1 and GluR2 expression.展开更多
基金supported by the Natural Science Foundation of Chongqing in China,No.CSTC2011jj A0013
文摘Ginsenoside Rgl is the major pharmacologically active component of ginseng, and is reported to have various therapeutic actions. To determine whether it induces the differentiation of neural stem cells, and whether neural stem cell transplantation after induction has therapeutic effects on hypoxic-ischemic encephalopathy, we cultured neural stem cells in 10-80 ~tM ginsenoside Rgl. Immunohistochemistry revealed that of the concentrations tested, 20 mM ginsenoside Rgl had the greatest differentiation-inducing effect and was the concentration used for subsequent exper- iments. Whole-cell patch clamp showed that neural stem cells induced by 20 jaM ginsenoside Rgl were more mature than non-induced cells. We then established neonatal rat models of hypox- ic-ischemic encephalopathy using the suture method, and ginsenoside Rgl-induced neural stem cells were transplanted via intracerebroventricular injection. These tests confirmed that neural stem cells induced by ginsenoside had fewer pathological lesions and had a significantly better behavioral capacity than model rats that received saline. Transplanted neural stem cells expressed neuron-specific enolase, and were mainly distributed in the hippocampus and cerebral cortex. The present data suggest that ginsenoside Rgl-induced neural stem cells can promote the partial recovery of complicated brain functions in models of hypoxic-ischemic encephalopathy.
基金financially supported by the National Natural Science Foundation of China,No.81771625(to XF)the Jiangsu Provincial Key Medical Discipline of China,No.ZDXKA2016013(to XF)the Pediatric Clinical Center of Suzhou City of China,No.Szzx201504(to XF)
文摘Secondary brain damage caused by hyperactivation of autophagy and inflammatory responses in neurons plays an important role in hypoxic-ischemic brain damage(HIBD).Although previous studies have implicated Toll-like receptor 4(TLR4)and nuclear factor kappa-B(NF-κB)in the neuroinflammatory response elicited by brain injury,the role and mechanisms of the TLR4-mediated autophagy signaling pathway in neonatal HIBD are still unclear.We hypothesized that this pathway can regulate brain damage by modulating neuron autophagy and neuroinflammation in neonatal rats with HIBD.Hence,we established a neonatal HIBD rat model using the Rice-Vannucci method,and injected 0.75,1.5,or 3 mg/kg of the TLR4 inhibitor resatorvid(TAK-242)30 minutes after hypoxic ischemia.Our results indicate that administering TAK-242 to neonatal rats after HIBD could significantly reduce the infarct volume and the extent of cerebral edema,alleviate neuronal damage and neurobehavioral impairment,and decrease the expression levels of TLR4,phospho-NF-κB p65,Beclin-1,microtubule-associated protein l light chain 3,tumor necrosis factor-α,and interleukin-1βin the hippocampus.Thus,TAK-242 appears to exert a neuroprotective effect after HIBD by inhibiting activation of autophagy and the release of inflammatory cytokines via inhibition of the TLR4/NF-κB signaling pathway.This study was approved by the Laboratory Animal Ethics Committee of Affiliated Hospital of Yangzhou University,China(approval No.20180114-15)on January 14,2018.
基金supported by Guangdong Province Science Research Project,No.B30502
文摘Hyperbaric oxygen therapy for the treatment of neonatal hypoxic-ischemic brain damage has been used clinically for many years, but its effectiveness remains controversial. In addition, the mechanism of this potential neuroprotective effect remains unclear. This study aimed to investigate the influence of hyperbaric oxygen on the proliferation of neural stem cells in the subventricular zone of neonatal Sprague-Dawley rats （7 days old） subjected to hypoxic-ischemic brain damage. Six hours after modeling, rats were treated with hyperbaric oxygen once daily for 7 days. Immunohistochemistry revealed that the number of 5-bromo-2＇-deoxyuridine positive and nestin positive cells in the subventricular zone of neonatal rats increased at day 3 after hypoxic-ischemic brain damage and peaked at day 5. After hyperbaric oxygen treatment, the number of 5-bromo-2＇- deoxyuddine positive and nestin positive cells began to increase at day 1, and was significantly higher than that in normal rats and model rats until day 21. Hematoxylin-eosin staining showed that hyperbaric oxygen treatment could attenuate pathological changes to brain tissue in neonatal rats, and reduce the number of degenerating and necrotic nerve cells. Our experimental findings indicate that hyperbaric oxygen treatment enhances the proliferation of neural stem cells in the subventricular zone of neonatal rats with hypoxic-ischemic brain damage, and has therapeutic potential for promoting neurological recovery following brain injury.
文摘目的探讨丰富环境（EE）对缺氧缺血性脑损伤（HIBD）新生大鼠学习记忆能力及海马区脑源性神经生长因子（BDNF）和突触素蛋白表达的影响。方法将40只7日龄Wistar雄性大鼠随机分为6 h EE干预（6 h EE）组、12 h EE干预（12 h EE）组、模型组和假手术组，每组10只。干预组和模型组均运用Rice法（1981）制备大鼠HIBD模型。干预组分别进行14 d的6 h和12 h的EE干预。运用Morris水迷宫行为学实验检测大鼠的学习记忆能力。Western blot法检测大鼠海马区BDNF、突触素蛋白的表达。结果4组大鼠训练期间的逃避潜伏期随着训练天数的增加逐渐降低，但4组大鼠之间的逃避潜伏期比较差异无统计学意义（F＝0.237，P〉0.05）。6 h EE组、12 h EE组和模型组新生大鼠在目标象限寻找平台的时间均短于假手术组，海马区BDNF和突触素蛋白（6 h EE组：0.529±0.038、0.889±0.027，12 h EE组：0.660±0.034、1.114±0.037，模型组：0.225±0.015、0.672±0.057）的表达相比于假手术组（0.803±0.026、1.347±0.092）也有所下降。与模型组相比，6 h EE组和12 h EE组新生大鼠在目标象限寻找平台的时间更长，并且海马区BDNF和突触素蛋白的表达显著上升。12 h EE组在目标象限寻找平台的时间以及海马区BDNF与突触素蛋白的表达情况都优于6 h EE组。结论EE能够改善HIBD幼鼠的学习记忆能力，保护神经元细胞，其机制可能与上调海马区BDNF和突触素蛋白表达有关。
基金supported by the National Natural Science Foundation of China,No.81471488,81271378,81502157,and 81501291the Key Medical Subjects of Jiangsu Province of China,No.XK201120+3 种基金the Jiangsu Province Key Research and Development of Special Funds in China,No.BE2015644the Science and Technology Project of Suzhou City of China,No.SYSD2013105,SYS201446,SYS201441the Public Health Technology Project of Suzhou City of China,No.SS201536the Department of Pediatrics Clinical Center of Suzhou City of China,No.Szzx201504
文摘Autophagy has been suggested to participate in the pathology of hypoxic-ischemic brain damage（HIBD）.However,its regulatory role in HIBD remains unclear and was thus examined here using a rat model.To induce HIBD,the left common carotid artery was ligated in neonatal rats,and the rats were subjected to hypoxia for 2 hours.Some of these rats were intraperitoneally pretreated with the autophagy inhibitor 3-methyladenine（10 m M in 10 μL） or the autophagy stimulator rapamycin（1 g/kg） 1 hour before artery ligation.Our findings demonstrated that hypoxia-ischemia-induced hippocampal injury in neonatal rats was accompanied by increased expression levels of the autophagy-related proteins light chain 3 and Beclin-1 as well as of the AMPA receptor subunit GluR 1,but by reduced expression of GluR 2.Pretreatment with the autophagy inhibitor 3-methyladenine blocked hypoxia-ischemia-induced hippocampal injury,whereas pretreatment with the autophagy stimulator rapamycin significantly augmented hippocampal injury.Additionally,3-methyladenine pretreatment blocked the hypoxia-ischemia-induced upregulation of Glu R1 and downregulation of GluR2 in the hippocampus.By contrast,rapamycin further elevated hippocampal Glu R1 levels and exacerbated decreased GluR2 expression levels in neonates with HIBD.Our results indicate that autophagy inhibition favors the prevention of HIBD in neonatal rats,at least in part,through normalizing Glu R1 and GluR2 expression.
