Evidence suggests that rapid changes to supporting glia may predispose individuals with spinal cord injury(SCI) to such comorbidities. Here, we interrogated the expression of astrocyte-and microglial-specific markers ...Evidence suggests that rapid changes to supporting glia may predispose individuals with spinal cord injury(SCI) to such comorbidities. Here, we interrogated the expression of astrocyte-and microglial-specific markers glial fibrillary acidic protein(GFAP) and ionized calcium binding adaptor molecule 1(Iba1) in the rat brain in the first 24 hours following SCI. Female Sprague-Dawley rats underwent thoracic laminectomy;half of the rats received a mild contusion injury at the level of the T10 vertebral body(SCI group), the other half did not(Sham group). Twenty-four hours post-surgery the amygdala, periaqueductal grey, prefrontal cortex, hypothalamus, lateral thalamus, hippocampus(dorsal and ventral) in rats were collected. GFAP and Iba1 m RNA and protein levels were measured by real-time quantitative polymerase chain reaction and Western blot. In SCI rats, GFAP m RNA and protein expression increased in the amygdala and hypothalamus. In contrast, gene and protein expression decreased in the thalamus and dorsal hippocampus. Interestingly, Iba1 transcripts and proteins were significantly diminished only in the dorsal and ventral hippocampus, where gene expression diminished. These findings demonstrate that as early as 24 hours post-SCI there are region-specific disruptions of GFAP and Iba1 transcript and protein levels in higher brain regions. All procedures were approved by the University of Technology Sydney Institutional Animal Care and Ethics Committee(UTS ACEC13-0069).展开更多
The neuroprotective effect against spinal cord ischemia/reperfusion injury in rats exerted by delayed xenon post-conditioning is stronger than that produced by immediate xenon post-conditioning. However, the mechanism...The neuroprotective effect against spinal cord ischemia/reperfusion injury in rats exerted by delayed xenon post-conditioning is stronger than that produced by immediate xenon post-conditioning. However, the mechanisms underlying this process remain unclear. Activated microglia are the main inflammatory cell type in the nervous system. The release of pro-inflammatory factors following microglial activation can lead to spinal cord damage, and inhibition of microglial activation can relieve spinal cord ischemia/reperfusion injury. To investigate how xenon regulates microglial activation and the release of inflammatory factors, a rabbit model of spinal cord ischemia/reperfusion injury was induced by balloon occlusion of the infrarenal aorta. After establishment of the model, two interventions were given： （1） immediate xenon post-conditioning—after reperfusion, inhalation of 50% xenon for 1 hour, 50% N2/50%O2 for 2 hours; （2） delayed xenon post-conditioning—after reperfusion, inhalation of 50% N2/50%O2 for 2 hours, 50% xenon for 1 hour. At 4, 8, 24, 48 and 72 hours after reperfusion, hindlimb locomotor function was scored using the Jacobs locomotor scale. At 72 hours after reperfusion, interleukin 6 and interleukin 10 levels in the spinal cord of each group were measured using western blot assays. Iba1 levels were determined using immunohistochemistry and a western blot assay. The number of normal neurons at the injury site was quantified using hematoxylin-eosin staining. At 72 hours after reperfusion, delayed xenon post-conditioning remarkably enhanced hindlimb motor function, increased the number of normal neurons at the injury site, decreased Iba1 levels, and inhibited interleukin-6 and interleukin-10 levels in the spinal cord.Immediate xenon post-conditioning did not noticeably affect the above-mentioned indexes. These findings indicate that delayed xenon post-conditioning after spinal cord injury improves the recovery of neurological function by reducing microglial activation and the release of interleukin-6 and interleukin-10.展开更多
BACKGROUND Acute pancreatitis(AP)and recurring AP are serious health care problems causing excruciating pain and potentially lethal outcomes due to sepsis.The validated caerulein-(CAE)induced mouse model of acute/recu...BACKGROUND Acute pancreatitis(AP)and recurring AP are serious health care problems causing excruciating pain and potentially lethal outcomes due to sepsis.The validated caerulein-(CAE)induced mouse model of acute/recurring AP produces secondary persistent hypersensitivity and anxiety-like behavioral changes for study.AIM To determine efficacy of acetyl-L-carnitine(ALC)to reduce pain-related behaviors and brain microglial activation along the pain circuitry in CAE-pancreatitis.METHODS Pancreatitis was induced with 6 hly intraperitoneal(i.p.)injections of CAE(50μg/kg),3 d a week for 6 wk in male C57BL/6J mice.Starting in week 4,mice received either vehicle or ALC until experiment’s end.Mechanical hypersensitivity was assessed with von Frey filaments.Heat hypersensitivity was determined with the hotplate test.Anxiety-like behavior was tested in week 6 using elevated plus maze and open field tests.Microglial activation in brain was quantified histologically by immunostaining for ionized calcium-binding adaptor molecule 1(Iba1).RESULTS Mice with CAE-induced pancreatitis had significantly reduced mechanical withdrawal thresholds and heat response latencies,indicating ongoing pain.Treatment with ALC attenuated inflammation-induced hypersensitivity,but hypersensitivity due to abdominal wall injury caused by repeated intraperitoneal injections persisted.Animals with pancreatitis displayed spontaneous anxiety-like behavior in the elevated plus maze compared to controls.Treatment with ALC resulted in increased numbers of rearing activity events,but time spent in“safety”was not changed.After all the abdominal injections,pancreata were translucent if excised at experiment’s end and opaque if excised on the subsequent day,indicative of spontaneous healing.Post mortem histopathological analysis performed on pancreas sections stained with Sirius Red and Fast Green identified wide-spread fibrosis and acinar cell atrophy in sections from mice with CAE-induced pancreatitis that was not rescued by treatment with ALC.Microglial Iba1 immunostaining was significantly increased in hippocampus,thalamus(intralaminar nuclei),hypothalamus,and amygdala of mice with CAE-induced pancreatitis compared to naïve controls but unchanged in the primary somatosensory cortex compared to naïves.CONCLUSION CAE-induced pancreatitis caused increased pain-related behaviors,pancreatic fibrosis,and brain microglial changes.ALC alleviated CAE-induced mechanical and heat hypersensitivity but not abdominal wall injury-induced hypersensitivity caused by the repeated injections.展开更多
目的研究大麻二酚(CBD)及其纳米制剂对小鼠抑郁样行为的影响及机制。方法腹腔注射脂多糖(LPS)诱导急性焦虑抑郁小鼠模型。将55只小鼠随机分组:长期实验分为正常(Con)组、模型(LPS)组、大麻二酚(CBD)组、纳米大麻二酚(NCBD)组、舍曲林(S...目的研究大麻二酚(CBD)及其纳米制剂对小鼠抑郁样行为的影响及机制。方法腹腔注射脂多糖(LPS)诱导急性焦虑抑郁小鼠模型。将55只小鼠随机分组:长期实验分为正常(Con)组、模型(LPS)组、大麻二酚(CBD)组、纳米大麻二酚(NCBD)组、舍曲林(SER)组,每组7只;短期实验分为Con组、LPS组、CBD组、NCBD组,每组5只。除Con组和LPS组给予蒸馏水,其余组灌胃给予25、50 mg/kg CBD及其纳米制剂。采用旷场和强迫游泳实验检测小鼠焦虑及抑郁样行为,Luxol Fast Blue髓鞘染色检测前额皮层中髓鞘形态,免疫荧光染色检测前额皮层中沉默信息调节因子2(SIRT2)、离子钙结合衔接分子1(Iba-1)和白细胞介素-1β(IL-1β)蛋白表达。结果长期实验中与Con组比较,LPS组小鼠穿梭次数减少(P<0.05),不动时间百分比增加(P<0.01),髓鞘数量及长度减少(P<0.05);与LPS组相比,CBD组、NCBD组、SER组小鼠抑郁样行为减少(P<0.01),髓鞘数量及长度增加(P<0.05)。短期实验中与Con组比较,LPS组小鼠焦虑抑郁样行为增加(P<0.05),SIRT2表达降低(P<0.01),Iba-1、IL-1β表达增加(P<0.01);与LPS组相比,CBD组、NCBD组小鼠焦虑样行为减少(P<0.05),SIRT2表达增加(P<0.01),Iba-1、IL-1β表达降低(P<0.05)。结论CBD及其纳米制剂可缓解小鼠焦虑、抑郁样行为,作用机制可能与逆转前额皮层中SIRT2蛋白表达、脱髓鞘变化、小胶质细胞活化及炎症因子的水平相关。展开更多
基金The University of Technology Sydney(UTS)Start-up Research Grant 2018 funded this study(to AC)。
文摘Evidence suggests that rapid changes to supporting glia may predispose individuals with spinal cord injury(SCI) to such comorbidities. Here, we interrogated the expression of astrocyte-and microglial-specific markers glial fibrillary acidic protein(GFAP) and ionized calcium binding adaptor molecule 1(Iba1) in the rat brain in the first 24 hours following SCI. Female Sprague-Dawley rats underwent thoracic laminectomy;half of the rats received a mild contusion injury at the level of the T10 vertebral body(SCI group), the other half did not(Sham group). Twenty-four hours post-surgery the amygdala, periaqueductal grey, prefrontal cortex, hypothalamus, lateral thalamus, hippocampus(dorsal and ventral) in rats were collected. GFAP and Iba1 m RNA and protein levels were measured by real-time quantitative polymerase chain reaction and Western blot. In SCI rats, GFAP m RNA and protein expression increased in the amygdala and hypothalamus. In contrast, gene and protein expression decreased in the thalamus and dorsal hippocampus. Interestingly, Iba1 transcripts and proteins were significantly diminished only in the dorsal and ventral hippocampus, where gene expression diminished. These findings demonstrate that as early as 24 hours post-SCI there are region-specific disruptions of GFAP and Iba1 transcript and protein levels in higher brain regions. All procedures were approved by the University of Technology Sydney Institutional Animal Care and Ethics Committee(UTS ACEC13-0069).
基金supported by the National Natural Science Foundation of China,No.81271387the Research Special Fund of Public Welfare and Health Department of China,No.201402009a grant form the National Key Technology R&D Program in China,No.Z141107002514031
文摘The neuroprotective effect against spinal cord ischemia/reperfusion injury in rats exerted by delayed xenon post-conditioning is stronger than that produced by immediate xenon post-conditioning. However, the mechanisms underlying this process remain unclear. Activated microglia are the main inflammatory cell type in the nervous system. The release of pro-inflammatory factors following microglial activation can lead to spinal cord damage, and inhibition of microglial activation can relieve spinal cord ischemia/reperfusion injury. To investigate how xenon regulates microglial activation and the release of inflammatory factors, a rabbit model of spinal cord ischemia/reperfusion injury was induced by balloon occlusion of the infrarenal aorta. After establishment of the model, two interventions were given： （1） immediate xenon post-conditioning—after reperfusion, inhalation of 50% xenon for 1 hour, 50% N2/50%O2 for 2 hours; （2） delayed xenon post-conditioning—after reperfusion, inhalation of 50% N2/50%O2 for 2 hours, 50% xenon for 1 hour. At 4, 8, 24, 48 and 72 hours after reperfusion, hindlimb locomotor function was scored using the Jacobs locomotor scale. At 72 hours after reperfusion, interleukin 6 and interleukin 10 levels in the spinal cord of each group were measured using western blot assays. Iba1 levels were determined using immunohistochemistry and a western blot assay. The number of normal neurons at the injury site was quantified using hematoxylin-eosin staining. At 72 hours after reperfusion, delayed xenon post-conditioning remarkably enhanced hindlimb motor function, increased the number of normal neurons at the injury site, decreased Iba1 levels, and inhibited interleukin-6 and interleukin-10 levels in the spinal cord.Immediate xenon post-conditioning did not noticeably affect the above-mentioned indexes. These findings indicate that delayed xenon post-conditioning after spinal cord injury improves the recovery of neurological function by reducing microglial activation and the release of interleukin-6 and interleukin-10.
基金United States Department of Veterans Affairs,VA Merit Grant,No.BX002695United States National Institute of Health,No.R01AG055359,No.R01GM126181 and No.R01NS39041-15.
文摘BACKGROUND Acute pancreatitis(AP)and recurring AP are serious health care problems causing excruciating pain and potentially lethal outcomes due to sepsis.The validated caerulein-(CAE)induced mouse model of acute/recurring AP produces secondary persistent hypersensitivity and anxiety-like behavioral changes for study.AIM To determine efficacy of acetyl-L-carnitine(ALC)to reduce pain-related behaviors and brain microglial activation along the pain circuitry in CAE-pancreatitis.METHODS Pancreatitis was induced with 6 hly intraperitoneal(i.p.)injections of CAE(50μg/kg),3 d a week for 6 wk in male C57BL/6J mice.Starting in week 4,mice received either vehicle or ALC until experiment’s end.Mechanical hypersensitivity was assessed with von Frey filaments.Heat hypersensitivity was determined with the hotplate test.Anxiety-like behavior was tested in week 6 using elevated plus maze and open field tests.Microglial activation in brain was quantified histologically by immunostaining for ionized calcium-binding adaptor molecule 1(Iba1).RESULTS Mice with CAE-induced pancreatitis had significantly reduced mechanical withdrawal thresholds and heat response latencies,indicating ongoing pain.Treatment with ALC attenuated inflammation-induced hypersensitivity,but hypersensitivity due to abdominal wall injury caused by repeated intraperitoneal injections persisted.Animals with pancreatitis displayed spontaneous anxiety-like behavior in the elevated plus maze compared to controls.Treatment with ALC resulted in increased numbers of rearing activity events,but time spent in“safety”was not changed.After all the abdominal injections,pancreata were translucent if excised at experiment’s end and opaque if excised on the subsequent day,indicative of spontaneous healing.Post mortem histopathological analysis performed on pancreas sections stained with Sirius Red and Fast Green identified wide-spread fibrosis and acinar cell atrophy in sections from mice with CAE-induced pancreatitis that was not rescued by treatment with ALC.Microglial Iba1 immunostaining was significantly increased in hippocampus,thalamus(intralaminar nuclei),hypothalamus,and amygdala of mice with CAE-induced pancreatitis compared to naïve controls but unchanged in the primary somatosensory cortex compared to naïves.CONCLUSION CAE-induced pancreatitis caused increased pain-related behaviors,pancreatic fibrosis,and brain microglial changes.ALC alleviated CAE-induced mechanical and heat hypersensitivity but not abdominal wall injury-induced hypersensitivity caused by the repeated injections.
文摘目的研究大麻二酚(CBD)及其纳米制剂对小鼠抑郁样行为的影响及机制。方法腹腔注射脂多糖(LPS)诱导急性焦虑抑郁小鼠模型。将55只小鼠随机分组:长期实验分为正常(Con)组、模型(LPS)组、大麻二酚(CBD)组、纳米大麻二酚(NCBD)组、舍曲林(SER)组,每组7只;短期实验分为Con组、LPS组、CBD组、NCBD组,每组5只。除Con组和LPS组给予蒸馏水,其余组灌胃给予25、50 mg/kg CBD及其纳米制剂。采用旷场和强迫游泳实验检测小鼠焦虑及抑郁样行为,Luxol Fast Blue髓鞘染色检测前额皮层中髓鞘形态,免疫荧光染色检测前额皮层中沉默信息调节因子2(SIRT2)、离子钙结合衔接分子1(Iba-1)和白细胞介素-1β(IL-1β)蛋白表达。结果长期实验中与Con组比较,LPS组小鼠穿梭次数减少(P<0.05),不动时间百分比增加(P<0.01),髓鞘数量及长度减少(P<0.05);与LPS组相比,CBD组、NCBD组、SER组小鼠抑郁样行为减少(P<0.01),髓鞘数量及长度增加(P<0.05)。短期实验中与Con组比较,LPS组小鼠焦虑抑郁样行为增加(P<0.05),SIRT2表达降低(P<0.01),Iba-1、IL-1β表达增加(P<0.01);与LPS组相比,CBD组、NCBD组小鼠焦虑样行为减少(P<0.05),SIRT2表达增加(P<0.01),Iba-1、IL-1β表达降低(P<0.05)。结论CBD及其纳米制剂可缓解小鼠焦虑、抑郁样行为,作用机制可能与逆转前额皮层中SIRT2蛋白表达、脱髓鞘变化、小胶质细胞活化及炎症因子的水平相关。
