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
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.