Project description:Traumatic injury to the adult mammalian central nervous system (CNS) leads to complex cellular responses. Among them, the scar tissue formed is generally recognized as a major obstacle to CNS repair, both by the production of inhibitory molecules and by the physical impedance of axon regrowth. Therefore, scar-modulating treatments have become a leading therapeutic intervention for CNS injury. To date, a variety of biological and pharmaceutical treatments, targeting scar modulation, have been tested in animal models of CNS injury, and a few are likely to enter clinical trials. In this review, we summarize current knowledge of the scar-modulating treatments according to their specific aims: (1) inhibition of glial and fibrotic scar formation, and (2) blockade of the production of scar-associated inhibitory molecules. The removal of existing scar tissue is also discussed as a treatment of choice. It is believed that only a combinatorial strategy is likely to help eliminate the detrimental effects of scar tissue on CNS repair.
Project description:Acute inflammation is a self-limiting, complex biological response mounted to combat pathogen invasion, to protect against tissue damage, and to promote tissue repair should it occur. However, unabated inflammation can be deleterious and contribute to injury and pathology. Interleukin-1? (IL-1?), a prototypical "pro-inflammatory" cytokine, is essential to cellular defense and tissue repair in nearly all tissues. With respect to brain, however, studies suggest that IL-1? has pleiotrophic effects. It acts as a neuromodulator in the healthy central nervous system (CNS), has been implicated in the pathogenic processes associated with a number of CNS maladies, but may also provide protection to the injured CNS. Here, we will review the physiological and pathophysiological functions of IL-1? in the central nervous system with regard to synaptic plasticity. With respect to disease, emphasis will be placed on stroke, epilepsy, Parkinson's disease and Alzheimer's disease where the ultimate injurious or reparative effects of IL-1? appear to depend on time, concentration and environmental milieu.
Project description:Nervous system injury is a frequent result of cancer therapy involving cranial irradiation, leaving patients with marked memory and other neurobehavioral disabilities. Here, we report an unanticipated link between bone marrow and brain in the setting of radiation injury. Specifically, we demonstrate that bone marrow-derived monocytes and macrophages are essential for structural and functional repair mechanisms, including regeneration of cerebral white matter and improvement in neurocognitive function. Using a granulocyte-colony stimulating factor (G-CSF) receptor knockout mouse model in combination with bone marrow cell transplantation, MRI, and neurocognitive functional assessments, we demonstrate that bone marrow-derived G-CSF-responsive cells home to the injured brain and are critical for altering neural progenitor cells and brain repair. Additionally, compared with untreated animals, animals that received G-CSF following radiation injury exhibited enhanced functional brain repair. Together, these results demonstrate that, in addition to its known role in defense and debris removal, the hematopoietic system provides critical regenerative drive to the brain that can be modulated by clinically available agents.
Project description:Traumatic injuries to the central nervous system (CNS) affect millions of people worldwide yet lack an effective treatment. These injuries contain infiltrating immune cells that can promote tissue repair and could be exploited for therapeutic benefit. Here, using single-cell RNA-sequencing of T cells infiltrating the injured CNS we demonstrate their clonal expansion and antigen specificity towards CNS derived self-peptides. We confirm the beneficial effect of these injury-associated autoimmune CD4+ T cells in murine models of optic nerve and spinal cord injury. Subsequently, using mRNA-based transient T cell receptor (TCR) reconstitution, we demonstrate a therapeutic T cell strategy to alleviate CNS injury. Treatment of CNS-injured mice with this therapy improved locomotion and alleviated histological signs of damage, through regulation of myeloid cells, without detrimental autoimmune side effects. This strategy provides a means of developing custom-designed T cell therapies for CNS injury, and possibly for other neurodegenerative disorders.
Project description:The sulfonylurea receptor 1 (Sur1)-regulated NC(Ca-ATP) channel is a nonselective cation channel that is regulated by intracellular calcium and adenosine triphosphate. The channel is not constitutively expressed, but is transcriptionally upregulated de novo in all cells of the neurovascular unit, in many forms of central nervous system (CNS) injury, including cerebral ischemia, traumatic brain injury (TBI), spinal cord injury (SCI), and subarachnoid hemorrhage (SAH). The channel is linked to microvascular dysfunction that manifests as edema formation and delayed secondary hemorrhage. Also implicated in oncotic cell swelling and oncotic (necrotic) cell death, the channel is a major molecular mechanism of 'accidental necrotic cell death' in the CNS. In animal models of SCI, pharmacological inhibition of Sur1 by glibenclamide, as well as gene suppression of Abcc8, prevents delayed capillary fragmentation and tissue necrosis. In models of stroke and TBI, glibenclamide ameliorates edema, secondary hemorrhage, and tissue damage. In a model of SAH, glibenclamide attenuates the inflammatory response due to extravasated blood. Clinical trials of an intravenous formulation of glibenclamide in TBI and stroke underscore the importance of recent advances in understanding the role of the Sur1-regulated NC(Ca-ATP) channel in acute ischemic, traumatic, and inflammatory injury to the CNS.
Project description:Sulfonylurea receptor 1 (SUR1) is a member of the adenosine triphosphate (ATP)-binding cassette (ABC) protein superfamily, encoded by Abcc8, and is recognized as a key mediator of central nervous system (CNS) cellular swelling via the transient receptor potential melastatin 4 (TRPM4) channel. Discovered approximately 20 years ago, this channel is normally absent in the CNS but is transcriptionally upregulated after CNS injury. A comprehensive review on the pathophysiology and role of SUR1 in the CNS was published in 2012. Since then, the breadth and depth of understanding of the involvement of this channel in secondary injury has undergone exponential growth: SUR1-TRPM4 inhibition has been shown to decrease cerebral edema and hemorrhage progression in multiple preclinical models as well as in early clinical studies across a range of CNS diseases including ischemic stroke, traumatic brain injury, cardiac arrest, subarachnoid hemorrhage, spinal cord injury, intracerebral hemorrhage, multiple sclerosis, encephalitis, neuromalignancies, pain, liver failure, status epilepticus, retinopathies and HIV-associated neurocognitive disorder. Given these substantial developments, combined with the timeliness of ongoing clinical trials of SUR1 inhibition, now, another decade later, we review advances pertaining to SUR1-TRPM4 pathobiology in this spectrum of CNS disease-providing an overview of the journey from patch-clamp experiments to phase III trials.
Project description:The brown ghost knifefish (Apteronotus leptorhynchus) is a weakly electric teleost fish of particular interest as a model organism for a variety of research areas in neuroscience, including neurophysiology, neuroethology, and neurobiology. This versatile model system has been more recently used in the study of central nervous system development and regeneration during adulthood, as well as in the study of vertebrate aging and senescence. Despite substantial scientific interest in this species, no genomic resources are currently available. After evaluating several trimming and transcript reconstruction strategies, de novo assembly using Trinity uncovered at least 11,847 unique components (“genes”) containing full or near-full length protein sequences based on alignment to a reference set of known Actinopterygii protein sequences, with as many as 42,459 components containing at least a partial protein-coding sequence, providing broad coverage of the proteome. Shotgun proteomics confirmed translation of open reading frames from over 2,000 transcripts, including alternative splice variants. Assignment of tandem mass spectra obtained was shown to be greatly improved with the assembly compared with using databases of sequences from closely related organisms.
Project description:Traumatic injuries to the central nervous system (CNS) affect millions of people worldwide yet lack an effective treatment. These injuries contain infiltrating immune cells that can promote tissue repair and could be exploited for therapeutic benefit. Here, using single-cell RNA-sequencing of T cells infiltrating the injured CNS we demonstrate their clonal expansion and antigen specificity towards CNS derived self-peptides. We confirm the beneficial effect of these injury-associated autoimmune CD4+ T cells in murine models of optic nerve and spinal cord injury. Subsequently, using mRNA-based transient T cell receptor (TCR) reconstitution, we demonstrate a therapeutic T cell strategy to alleviate CNS injury. Treatment of CNS-injured mice with this therapy improved locomotion and alleviated histological signs of damage, through regulation of myeloid cells, without detrimental autoimmune side effects. This strategy provides a means of developing custom-designed T cell therapies for CNS injury, and possibly for other neurodegenerative disorders.
Project description:Traumatic injuries to the central nervous system (CNS) affect millions of people worldwide yet lack an effective treatment. These injuries contain infiltrating immune cells that can promote tissue repair and could be exploited for therapeutic benefit. Here, using single-cell RNA-sequencing of T cells infiltrating the injured CNS we demonstrate their clonal expansion and antigen specificity towards CNS derived self-peptides. We confirm the beneficial effect of these injury-associated autoimmune CD4+ T cells in murine models of optic nerve and spinal cord injury. Subsequently, using mRNA-based transient T cell receptor (TCR) reconstitution, we demonstrate a therapeutic T cell strategy to alleviate CNS injury. Treatment of CNS-injured mice with this therapy improved locomotion and alleviated histological signs of damage, through regulation of myeloid cells, without detrimental autoimmune side effects. This strategy provides a means of developing custom-designed T cell therapies for CNS injury, and possibly for other neurodegenerative disorders.