Long non-coding RNAs regulate brain microvascular endothelial cell death, the inflammatory response and angiogenesis during and after ischemia/reperfusion and oxygen-glucose deprivation/reoxygenation（OGD/R） insults....Long non-coding RNAs regulate brain microvascular endothelial cell death, the inflammatory response and angiogenesis during and after ischemia/reperfusion and oxygen-glucose deprivation/reoxygenation（OGD/R） insults. The long non-coding RNA, SNHG12, is upregulated after ischemia/reperfusion and OGD/R in microvascular endothelial cells of the mouse brain. However, its role in ischemic stroke has not been studied. We hypothesized that SNHG12 positively regulates ischemic stroke, and therefore we investigated its mechanism of action. We established an OGD/R mouse cell model to mimic ischemic stroke by exposing brain microvascular endothelial cells to OGD for 0, 2, 4, 8, 16 or 24 hours and reoxygenation for 4 hours. Quantitative real-time polymerase chain reaction showed that SNHG12 levels in brain microvascular endothelial cells increased with respect to OGD exposure time. Brain microvascular endothelial cells were transfected with pc DNA-control, pc DNA-SNHG12, si-control, or si-SNHG12. After exposure to OGD for 16 hours, these cells were then analyzed by 3-（4,5-dimethyl-2-thiazolyl）-2,5-diphenyl-2-H-tetrazolium bromide, trypan blue exclusion, western blot, and capillary-like tube formation assays. Overexpression of SNHG12 inhibited brain microvascular endothelial cell death and the inflammatory response but promoted angiogenesis after OGD/R, while SNHG12 knockdown had the opposite effects. miR-199a was identified as a target of SNHG12, and SNHG12 overexpression reversed the effect of miR-199a on brain microvascular endothelial cell death, the inflammatory response, and angiogenesis. These findings suggest that SNHG12 suppresses endothelial cell injury induced by OGD/R by targeting miR-199a.展开更多
AIM: Nuclear factor kappa B (NF-κB) regulates a large number of genes involved in the inflammatory response to critical illnesses, but it is not known if and how NF-KB is activated and intercellular adhesion molecule...AIM: Nuclear factor kappa B (NF-κB) regulates a large number of genes involved in the inflammatory response to critical illnesses, but it is not known if and how NF-KB is activated and intercellular adhesion molecule-1 (ICAM-1) expressed in the gut following traumatic brain injury (TBI). The aim of current study was to investigate the temporal pattern of intestinal NF-κB activation and ICAM-1 expression following TBI. METHODS: Male Wistar rats were randomly divided into six groups (6 rats in each group) including controls with sham operation and TBI groups at hours 3, 12, 24, and 72, and on d 7. Parietal brain contusion was adopted using weight-dropping method. All rats were decapitated at corresponding time point and mid-jejunum samples were taken. NF-KB binding activity in jejunal tissue was measured using EMSA. Immunohistochemistry was used for detection of ICAM-1 expression in jejunal samples. RESULTS: There was a very low NF-κB binding activity and little ICAM-1 expression in the gut of control rats after sham surgery. NF-KB binding activity in jejunum significantly increased by 160% at 3 h following TBI (P<0.05 vs control), peaked at 72 h (500% increase) and remained elevated on d 7 post-injury by 390% increase. Compared to controls, ICAM-1 was significantly up-regulated on the endothelia of microvessels in villous interstitium and lamina propria by 24 h following TBI and maximally expressed at 72 h post-injury (P<0.001). The endothelial ICAM-1 immunoreactivity in jejunal mucosa still remained strong on d 7 post-injury. The peak of NF-κB activation and endothelial ICAM-1 expression coincided in time with the period during which secondary mucosal injury of the gut was also at their culmination following TBI. CONCLUSION: TBI could induce an immediate and persistent up-regulation of NF-κB activity and subsequent up-regulation of ICAM-1 expression in the intestine. Inflammatory response mediated by increased NF-κB activation and ICAM-1 expression may play an important role in the pathogenesis of acute gut mucosal injury following TBI.展开更多
目的:探讨蛋白激酶RNA样ER激酶(protein kinase RNA-like ER kinase,PERK)信号通路介导的线粒体未折叠蛋白反应(mitochondrial unfolded protein response,mtUPR)在缺氧缺血性脑损伤(hypoxic-ischemic brain injury,HIBI)中的作用。方法...目的:探讨蛋白激酶RNA样ER激酶(protein kinase RNA-like ER kinase,PERK)信号通路介导的线粒体未折叠蛋白反应(mitochondrial unfolded protein response,mtUPR)在缺氧缺血性脑损伤(hypoxic-ischemic brain injury,HIBI)中的作用。方法:将大鼠随机分为假手术(Sham)组和5个HIBI亚组(HIBI后3、6、12、24、48 h)。用于蛋白质印迹检测PERK、转录激活因子4(activating transcription factor 4,ATF4)、热休克蛋白60(heat shock protein 60,HSP60)蛋白的时程表达。将大鼠随机分为Sham组、HIBI组、HIBI+PERK组和HIBI+载体(Vector)组,每组15只。HIBI+PERK组和HIBI+Vector组大鼠在HIBI手术前1 h,将基于腺病毒相关病毒(adeno-associated virus,AAV)的PERK过表达质粒或AAV载体注射到脑室内,用于特异性表达PERK。在HIBI后24 h进行FJC染色分析神经元变性和DHE染色、酶联免疫吸附试验分析氧化应激。将大鼠随机分为Sham组、HIBI组、HIBI+PERK激动剂(CCT020312)组,每组12只。在HIBI手术前1 h,向HIBI+CCT020312组大鼠脑室内注射CCT020312。在HIBI后3周进行开阔场地测试和莫里斯水迷宫测试。结果:与Sham组相比,PERK、ATF4、HSP60在HIBI后3 h开始明显升高,在12 h达到高峰,然后逐渐下降,直到48 h(F=60.23、56.72、74.31,均P<0.001)。与HIBI组相比,HIBI+PERK组神经元变性的数量(100.2±3.1 vs. 582.4±15.7,P<0.001)、活性氧(reactive oxygen species,ROS)(42.4±2.9 vs. 17.7±2.1,P<0.01)、丙二醛(Malondialdehyde,MDA)(0.81±0.06 vs. 0.54±0.04,P<0.001)水平显著降低,和谷胱甘肽过氧化物酶(glutathione peroxidase,GSHPx)(112.4±3.6 vs. 177.5±6.6,P<0.05)、超氧化物歧化酶(superoxide Dismutase,SOD)活性(46.3±1.9 vs. 64.2±2.3,P<0.05)活性明显增加。与Sham组相比,HIBI组大鼠海马组织中PERK(1.00±0.03 vs. 1.66±0.08,P<0.01)、ATF4(1.00±0.04 vs.1.53±0.06,P<0.05)、动力蛋白相关蛋白1(dynamin-related protein 1,Drp1)(1.00±0.02 vs. 1.98±0.07,P<0.01)、HSP60(1.00±0.03 vs. 1.37±0.04,P<0.05)蛋白表达均明显增加(P<0.05)。与HIBI组相比,HIBI+PERK组大鼠海马组织中PERK(1.66±0.08vs. 2.95±0.17,P<0.01)、ATF4(1.53±0.06 vs. 3.42±0.22,P<0.01)、HSP60(1.37±0.04 vs. 2.03±0.09,P<0.05)蛋白表达均明显增加(F=46.72、30.63、20.64,P<0.001),和Drp1(1.98±0.07 vs. 1.04±0.05,P<0.05)蛋白表达明显降低(F=35.72,P<0.001)。HIBI+CCT020312组的平均逃避潜伏期和平台穿越次数均较HIBI组明显增加(F=246.84、113.62,P<0.001)。结论:PERK减轻HIBI模型诱导的氧化应激和神经元凋亡,其机制可能涉及PERK/ATF4信号通路对mtUPR的调节。通过CCT020312给药具有神经保护作用。展开更多
基金supported by the Natural Science Foundation of Hainan Province of China,No.817334
文摘Long non-coding RNAs regulate brain microvascular endothelial cell death, the inflammatory response and angiogenesis during and after ischemia/reperfusion and oxygen-glucose deprivation/reoxygenation（OGD/R） insults. The long non-coding RNA, SNHG12, is upregulated after ischemia/reperfusion and OGD/R in microvascular endothelial cells of the mouse brain. However, its role in ischemic stroke has not been studied. We hypothesized that SNHG12 positively regulates ischemic stroke, and therefore we investigated its mechanism of action. We established an OGD/R mouse cell model to mimic ischemic stroke by exposing brain microvascular endothelial cells to OGD for 0, 2, 4, 8, 16 or 24 hours and reoxygenation for 4 hours. Quantitative real-time polymerase chain reaction showed that SNHG12 levels in brain microvascular endothelial cells increased with respect to OGD exposure time. Brain microvascular endothelial cells were transfected with pc DNA-control, pc DNA-SNHG12, si-control, or si-SNHG12. After exposure to OGD for 16 hours, these cells were then analyzed by 3-（4,5-dimethyl-2-thiazolyl）-2,5-diphenyl-2-H-tetrazolium bromide, trypan blue exclusion, western blot, and capillary-like tube formation assays. Overexpression of SNHG12 inhibited brain microvascular endothelial cell death and the inflammatory response but promoted angiogenesis after OGD/R, while SNHG12 knockdown had the opposite effects. miR-199a was identified as a target of SNHG12, and SNHG12 overexpression reversed the effect of miR-199a on brain microvascular endothelial cell death, the inflammatory response, and angiogenesis. These findings suggest that SNHG12 suppresses endothelial cell injury induced by OGD/R by targeting miR-199a.
基金Supported by Scientific Research Foundation of the Chinese PLA Key Medical Programs During the 10th Five-Year Plan Period, No. 01Z011
文摘AIM: Nuclear factor kappa B (NF-κB) regulates a large number of genes involved in the inflammatory response to critical illnesses, but it is not known if and how NF-KB is activated and intercellular adhesion molecule-1 (ICAM-1) expressed in the gut following traumatic brain injury (TBI). The aim of current study was to investigate the temporal pattern of intestinal NF-κB activation and ICAM-1 expression following TBI. METHODS: Male Wistar rats were randomly divided into six groups (6 rats in each group) including controls with sham operation and TBI groups at hours 3, 12, 24, and 72, and on d 7. Parietal brain contusion was adopted using weight-dropping method. All rats were decapitated at corresponding time point and mid-jejunum samples were taken. NF-KB binding activity in jejunal tissue was measured using EMSA. Immunohistochemistry was used for detection of ICAM-1 expression in jejunal samples. RESULTS: There was a very low NF-κB binding activity and little ICAM-1 expression in the gut of control rats after sham surgery. NF-KB binding activity in jejunum significantly increased by 160% at 3 h following TBI (P<0.05 vs control), peaked at 72 h (500% increase) and remained elevated on d 7 post-injury by 390% increase. Compared to controls, ICAM-1 was significantly up-regulated on the endothelia of microvessels in villous interstitium and lamina propria by 24 h following TBI and maximally expressed at 72 h post-injury (P<0.001). The endothelial ICAM-1 immunoreactivity in jejunal mucosa still remained strong on d 7 post-injury. The peak of NF-κB activation and endothelial ICAM-1 expression coincided in time with the period during which secondary mucosal injury of the gut was also at their culmination following TBI. CONCLUSION: TBI could induce an immediate and persistent up-regulation of NF-κB activity and subsequent up-regulation of ICAM-1 expression in the intestine. Inflammatory response mediated by increased NF-κB activation and ICAM-1 expression may play an important role in the pathogenesis of acute gut mucosal injury following TBI.
文摘目的:探讨蛋白激酶RNA样ER激酶(protein kinase RNA-like ER kinase,PERK)信号通路介导的线粒体未折叠蛋白反应(mitochondrial unfolded protein response,mtUPR)在缺氧缺血性脑损伤(hypoxic-ischemic brain injury,HIBI)中的作用。方法:将大鼠随机分为假手术(Sham)组和5个HIBI亚组(HIBI后3、6、12、24、48 h)。用于蛋白质印迹检测PERK、转录激活因子4(activating transcription factor 4,ATF4)、热休克蛋白60(heat shock protein 60,HSP60)蛋白的时程表达。将大鼠随机分为Sham组、HIBI组、HIBI+PERK组和HIBI+载体(Vector)组,每组15只。HIBI+PERK组和HIBI+Vector组大鼠在HIBI手术前1 h,将基于腺病毒相关病毒(adeno-associated virus,AAV)的PERK过表达质粒或AAV载体注射到脑室内,用于特异性表达PERK。在HIBI后24 h进行FJC染色分析神经元变性和DHE染色、酶联免疫吸附试验分析氧化应激。将大鼠随机分为Sham组、HIBI组、HIBI+PERK激动剂(CCT020312)组,每组12只。在HIBI手术前1 h,向HIBI+CCT020312组大鼠脑室内注射CCT020312。在HIBI后3周进行开阔场地测试和莫里斯水迷宫测试。结果:与Sham组相比,PERK、ATF4、HSP60在HIBI后3 h开始明显升高,在12 h达到高峰,然后逐渐下降,直到48 h(F=60.23、56.72、74.31,均P<0.001)。与HIBI组相比,HIBI+PERK组神经元变性的数量(100.2±3.1 vs. 582.4±15.7,P<0.001)、活性氧(reactive oxygen species,ROS)(42.4±2.9 vs. 17.7±2.1,P<0.01)、丙二醛(Malondialdehyde,MDA)(0.81±0.06 vs. 0.54±0.04,P<0.001)水平显著降低,和谷胱甘肽过氧化物酶(glutathione peroxidase,GSHPx)(112.4±3.6 vs. 177.5±6.6,P<0.05)、超氧化物歧化酶(superoxide Dismutase,SOD)活性(46.3±1.9 vs. 64.2±2.3,P<0.05)活性明显增加。与Sham组相比,HIBI组大鼠海马组织中PERK(1.00±0.03 vs. 1.66±0.08,P<0.01)、ATF4(1.00±0.04 vs.1.53±0.06,P<0.05)、动力蛋白相关蛋白1(dynamin-related protein 1,Drp1)(1.00±0.02 vs. 1.98±0.07,P<0.01)、HSP60(1.00±0.03 vs. 1.37±0.04,P<0.05)蛋白表达均明显增加(P<0.05)。与HIBI组相比,HIBI+PERK组大鼠海马组织中PERK(1.66±0.08vs. 2.95±0.17,P<0.01)、ATF4(1.53±0.06 vs. 3.42±0.22,P<0.01)、HSP60(1.37±0.04 vs. 2.03±0.09,P<0.05)蛋白表达均明显增加(F=46.72、30.63、20.64,P<0.001),和Drp1(1.98±0.07 vs. 1.04±0.05,P<0.05)蛋白表达明显降低(F=35.72,P<0.001)。HIBI+CCT020312组的平均逃避潜伏期和平台穿越次数均较HIBI组明显增加(F=246.84、113.62,P<0.001)。结论:PERK减轻HIBI模型诱导的氧化应激和神经元凋亡,其机制可能涉及PERK/ATF4信号通路对mtUPR的调节。通过CCT020312给药具有神经保护作用。
