GENETICALLY-MODIFIED MACROPHAGES ACCELERATE MYELIN REPAIR
Ontology highlight
ABSTRACT:
SUBMITTER: Ms. Marie-Stephane Aigrot
PROVIDER: S-SCDT-EMM-2021-14759 | biostudies-other |
REPOSITORIES: biostudies-other
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Project description:The leukodystrophies are rare and serious genetic disorders of the central nervous system that primarily affect children who frequently die early in life or have significantly delayed motor and mental milestones that result in long-term disability. Although with some of these disorders, early intervention with bone marrow or cord blood transplantation has been proven useful, it has not yet been determined that such therapies promote myelin repair of the central nervous system. Research on experimental therapies aimed at myelin repair is aided by the ability to test cell replacement strategies in genetic models in which the mutations and neuropathology match the human disorder. Thus, models exist of Pelizaeus-Merzbacher disease and the lysosomal storage disorder, Krabbe disease, which reflect the clinical and pathological course of the human disorders. Collectively, animals with mutations in myelin genes are called the myelin mutants, and they include rodent models such as the shiverer mouse that have been extensively used to study myelination by exogenous cell transplantation. These studies have encompassed many permutations of the age of the recipient, type of transplanted cell, site of engraftment, and so forth, and they offer hope that the scaling up of myelin produced by transplanted cells will have clinical significance in treating patients. Here we review these models and discuss their relative importance and use in such translational approaches. We discuss how grafts are identified and functional outcomes are measured. Finally, we briefly discuss the cells that have been successfully transplanted, which may be used in future clinical trials.
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Project description:Glutamate signaling may orchestrate oligodendrocyte precursor cell (OPC)development and myelin regeneration through the activation of glutamate receptors at OPC-neuron-synapses.D-Aspartate is a D-aminoacid exerting modulatory actions at glutamatergic synapses. Chronic administration of D-Aspartate has been proposed as therapeutic treatment in diseases related to myelin dysfunction and NMDA receptors hypofunction, including schizophrenia and cognitive deficits.Here we show, by using an in vivo remyelination model, that administration of D-Aspartate during remyelination improved motor coordination, accelerated myelin recovery and significantly increased the number of small-diameter myelinated axons.Chronically administered during demyelination, D-Aspartate also attenuated myelin loss and inflammation. Interestingly, D-Aspartate exposure stimulated OPC maturation and accelerated developmental myelination in organotypic cerebellar slices. D-Aspartate promoting effects on OPC maturation involved the activation of glutamate transporters, AMPA and NMDA receptors and the Na+/Ca2+ exchanger NCX3. While blocking NMDA or NCX3 significantly prevented D-Aspartate induced [Ca2+]i oscillations, blocking AMPA and glutamate transporters prevented both the initial and oscillatory [Ca2+]i response as well as D-Aspartate-induced inward currents in OPC. Our findings reveal that D-Aspartate treatment may represent a novel strategy for promoting myelin recovery.
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