The limited regenerative capacity of neurons in the central nervous system and the formation of an inhibitory environment at the site of injury represent a major challenge for regeneration and repair of injuries to the spinal cord. In this sense, the influence of mesenchymal stem cells (MSC) in the spinal Cord microenvironment, glial scar formation and its effects on inflammation, control of reactive gliosis, neuronal survival and synaptic plasticity in injured motoneurons, becomes an important object of study. Additionally, the use of fibrin sealant as a substrate for the MSC may contribuit positively to the successful regeneration in the CNS. MSC modify the inflammatory environment in the acute phase and reduce inhibitory effects of glial scar in the subacute and chronic phase, providing a permissive environment for axonal extension. It can also provide growth factors that promote survival and axonal elongation through injury to the spinal cord. To evaluate the neuroprotective, regenerative, modulatory of inflammation and glial scar, the treatment with fibrin sealant and / or therapy with MSC after a central lesion, Will be performed a perforating injury in the region of the right anterior funiculus in spinal levels L4 and L5 ( n = 5 per experimental group). After survival rate 7 days after the lesion will be performed (1) RT-PCR in real time to VEGF, IL4, IL3, TNF, IL6, arginase-1, iNOS, and TGF² and (2) with double labeling immunohistochemistry for IBA1 (marker of microglia and macrophages) and Arginase-1 (macrophage marker M2) in situ to demonstrate the presence / reactivity of such cells. After 14 days survival will be performed (1) by counting neuronal Nissl staining, and (2) immunohistochemistry for synaptophysin (a marker of synapses). With survival of 8 weeks, will be held (1) behavioral test for gait analysis of animals (Catwalk), (2) analysis of the glial scar by FISH (fluorescence in situ hybridization) and IH. In this procedure will be doubly labeled GFAP (a marker for astrocytes - IH) and chondroitin sulfate (FISH), (3) analysis of neuronal regeneration by glial scar by FISH and IH. In this procedure will be doubly labeled neurofilaments (IH) and GAP-43 (marker of neuron regeneration - FISH) and (4) qualitative analysis of the production of collagen and laminin by MSC through IH.
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