Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 9 de 9
Filter
Add more filters










Language
Publication year range
1.
Int J Mol Sci ; 24(17)2023 Sep 04.
Article in English | MEDLINE | ID: mdl-37686446

ABSTRACT

Tissue engineering for spinal cord injury (SCI) remains a complex and challenging task. Biomaterial scaffolds have been suggested as a potential solution for supporting cell survival and differentiation at the injury site. However, different biomaterials display multiple properties that significantly impact neural tissue at a cellular level. Here, we evaluated the behavior of different cell lines seeded on chitosan (CHI), poly (ε-caprolactone) (PCL), and poly (L-lactic acid) (PLLA) scaffolds. We demonstrated that the surface properties of a material play a crucial role in cell morphology and differentiation. While the direct contact of a polymer with the cells did not cause cytotoxicity or inhibit the spread of neural progenitor cells derived from neurospheres (NPCdn), neonatal rat spinal cord cells (SCC) and NPCdn only attached and matured on PCL and PLLA surfaces. Scanning electron microscopy and computational analysis suggested that cells attached to the material's surface emerged into distinct morphological populations. Flow cytometry revealed a higher differentiation of neural progenitor cells derived from human induced pluripotent stem cells (hiPSC-NPC) into glial cells on all biomaterials. Immunofluorescence assays demonstrated that PCL and PLLA guided neuronal differentiation and network development in SCC. Our data emphasize the importance of selecting appropriate biomaterials for tissue engineering in SCI treatment.


Subject(s)
Induced Pluripotent Stem Cells , Nerve Tissue , Spinal Cord Injuries , Spinal Cord Regeneration , Animals , Rats , Humans , Biocompatible Materials/pharmacology , Tissue Engineering , Spinal Cord Injuries/therapy
2.
Clinics (Sao Paulo) ; 77: 100006, 2022.
Article in English | MEDLINE | ID: mdl-35193085

ABSTRACT

OBJECTIVES: To evaluate the functional and immunohistochemical effects of ganglioside GM1 and erythropoietin following experimental spinal cord injury. METHODS: Thirty-two male BALB/c mice were subjected to experimental spinal cord injury using the NYU Impactor device and were randomly divided into the following groups: GM1 group, receiving standard ganglioside GM1 (30 mg/kg); erythropoietin group, receiving erythropoietin (1000 IU/kg); combination group, receiving both drugs; and control group, receiving saline (0.9%). Animals were evaluated according to the Basso Mouse Scale (BMS) and Hindlimb Mouse Function Score (MFS). After euthanasia, the immunohistochemistry of the medullary tissue of mice was analyzed. All animals received intraperitoneal treatment. RESULTS: The GM1 group had higher BMS and MFS scores at the end of the experiment when compared to all other groups. The combination group had higher BMS and MFS scores than the erythropoietin and control groups. The erythropoietin group had higher BMS and MFS scores than the control group. Immunohistochemical tissue analysis showed a significant difference among groups. There was a significant increase in myelinated axons and in the myelinated axon length in the erythropoietin group when compared to the other intervention groups (p < 0.01). CONCLUSIONS: Erythropoietin and GM1 have therapeutic effects on axonal regeneration in mice subjected to experimental spinal cord injury, and administration of GM1 alone had the highest scores on the BMS and MFS scales.


Subject(s)
Erythropoietin , Spinal Cord Injuries , Animals , Disease Models, Animal , Epoetin Alfa/therapeutic use , Erythropoietin/pharmacology , Erythropoietin/therapeutic use , G(M1) Ganglioside/pharmacology , G(M1) Ganglioside/therapeutic use , Injections, Intraperitoneal , Male , Mice , Spinal Cord
3.
Clinics ; 77: 100006, 2022. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1375180

ABSTRACT

ABSTRACT Objectives: To evaluate the functional and immunohistochemical effects of ganglioside GM1 and erythropoietin following experimental spinal cord injury. Methods: Thirty-two male BALB/c mice were subjected to experimental spinal cord injury using the NYU Impactor device and were randomly divided into the following groups: GM1 group, receiving standard ganglioside GM1 (30 mg/kg); erythropoietin group, receiving erythropoietin (1000 IU/kg); combination group, receiving both drugs; and control group, receiving saline (0.9%). Animals were evaluated according to the Basso Mouse Scale (BMS) and Hindlimb Mouse Function Score (MFS). After euthanasia, the immunohistochemistry of the medullary tissue of mice was analyzed. All animals received intraperitoneal treatment. Results: The GM1 group had higher BMS and MFS scores at the end of the experiment when compared to all other groups. The combination group had higher BMS and MFS scores than the erythropoietin and control groups. The erythropoietin group had higher BMS and MFS scores than the control group. Immunohistochemical tissue analysis showed a significant difference among groups. There was a significant increase in myelinated axons and in the myelinated axon length in the erythropoietin group when compared to the other intervention groups (p < 0.01). Conclusion: Erythropoietin and GM1 have therapeutic effects on axonal regeneration in mice subjected to experimental spinal cord injury, and administration of GM1 alone had the highest scores on the BMS and MFS scales.

4.
Mol Neurobiol ; 57(4): 2085-2100, 2020 Apr.
Article in English | MEDLINE | ID: mdl-31927725

ABSTRACT

Spinal cord injury (SCI) causes temporary disabilities or permanent effects including neuropathic pain and spastiscity. The damage often results from mechanical trauma, which in turn triggers the neuroinflammatory process. Neuroinflammation plays essential roles in the structural, biochemical, and cellular changes that take place in the spinal cord after the injury. Indeed, SCI activates many different signaling pathways that coordinate the resulting cellular responses. While neuroinflammation serves as a physiological reaction to harmful stimuli, it is clear that long-lasting inflammatory response leads to aggravation of the neurodegenerative processes, becoming detrimental to recovery post-injury. In this context, we present some possible therapeutic targets in these activated signaling pathways and provide new perspectives for SCI treatment based on recently developed technologies, including clustered regularly interspaced short palindromic repeats (CRISPR)-based methods (including prime editing), optogenetics, and designer receptor exclusively activated by designer drugs (DREADDs). We critically analyze the recent advances in the deployment of these methods focusing on the control of the initial neuroinflammatory response. We then propose alternatives and provide new avenues for SCI treatment based on these emerging technologies.


Subject(s)
CRISPR-Cas Systems/genetics , Designer Drugs/therapeutic use , Gene Editing , Optogenetics , Spinal Cord Injuries/therapy , Animals , Humans , Translational Research, Biomedical
5.
Sci Rep ; 9(1): 14063, 2019 Oct 01.
Article in English | MEDLINE | ID: mdl-31575916

ABSTRACT

During the progression of the neurodegenerative process, mitochondria participates in several intercellular signaling pathways. Voltage-dependent anion-selective channel 1 (VDAC1) is a mitochondrial porin involved in the cellular metabolism and apoptosis intrinsic pathway in many neuropathological processes. In spinal cord injury (SCI), after the primary cell death, a secondary response that comprises the release of pro-inflammatory molecules triggers apoptosis, inflammation, and demyelination, often leading to the loss of motor functions. Here, we investigated the functional role of VDAC1 in the neurodegeneration triggered by SCI. We first determined that in vitro targeted ablation of VDAC1 by specific morpholino antisense nucleotides (MOs) clearly promotes neurite retraction, whereas a pharmacological blocker of VDAC1 oligomerization (4, 4'-diisothiocyanatostilbene-2, 2'-disulfonic acid, DIDS), does not cause this effect. We next determined that, after SCI, VDAC1 undergoes conformational changes, including oligomerization and N-terminal exposition, which are important steps in the triggering of apoptotic signaling. Considering this, we investigated the effects of DIDS in vivo application after SCI. Interestingly, blockade of VDAC1 oligomerization decreases the number of apoptotic cells without interfering in the neuroinflammatory response. DIDS attenuates the massive oligodendrocyte cell death, subserving undisputable motor function recovery. Taken together, our results suggest that the prevention of VDAC1 oligomerization might be beneficial for the clinical treatment of SCI.


Subject(s)
Neurites/metabolism , Spinal Cord Injuries/physiopathology , Spinal Cord/metabolism , Voltage-Dependent Anion Channel 1/physiology , Animals , Blotting, Western , Cells, Cultured , Female , Fluorescent Antibody Technique , Male , Microscopy, Fluorescence , Rats , Rats, Wistar , Spinal Cord/physiopathology , Spinal Cord Injuries/metabolism , Voltage-Dependent Anion Channel 1/metabolism
6.
Mol Neurobiol ; 53(3): 2016-2028, 2016 Apr.
Article in English | MEDLINE | ID: mdl-25862375

ABSTRACT

Extracellular vesicles (EVs), including exosomes, microvesicles and apoptotic bodies, participate in intercellular communication, and particularly, in paracrine and endocrine signalling. The EVs and their specific contents have been considered hallmarks of different diseases. It has been recently discovered that EVs can co-transport nucleic acids such as DNAs, ribosomal RNAs, circular RNAs (circRNAs), long noncoding RNAs (lnRNAs) and microRNAs (miRNAs). miRNAs are important regulators of gene expression at the post-transcriptional level, although they may also play other roles. Recent evidence supports the hypothesis that miRNAs can activate Toll-like receptors (TLRs) under certain circumstances. TLRs belong to a multigene family of immune system receptors and have been recently described in the nervous system. In the immune system, TLRs are important for the recognition of the invading microorganisms, whereas in the nervous system, they recognise endogenous ligands released by undifferentiated or necrotic/injured cells. In the neuronal disease field, TLRs activity has been associated with amyotrophic lateral sclerosis (ALS), stroke, Alzheimer's and Parkinson's disease. Herein, we reviewed the current knowledge of the relationship between miRNA release by EVs and the inflammation signalling triggered by TLRs in neighbouring cells or during long-distance cell-to-cell communication. We highlight novel aspects of this communication mechanism, offering a valuable insight into such pathways in health and disease.


Subject(s)
Brain Diseases/metabolism , Exosomes/metabolism , MicroRNAs/metabolism , Toll-Like Receptors/metabolism , Animals , Extracellular Vesicles/metabolism , Humans , RNA Transport
7.
PLoS One ; 8(4): e60486, 2013.
Article in English | MEDLINE | ID: mdl-23585836

ABSTRACT

In this study, we describe a simple and reliable method to study neuroprotective effects in living and organized neural tissue. This method, which was based on retinal explants for in vivo focal lesions, was conceived as a collection of modular procedures, which can be customized for particular demands. With this model, it is possible to combine immunohistochemistry with image data analysis to track the two- or three-dimensional redistribution of proteins as a time/space function of primary cell loss. At the same time, it is possible to finely control the exposure of the tissue to specific drugs and molecules. In order to illustrate the use of the proposed method, we tested the effects of two different nanotube compounds on retinal explant viability. Transcriptome analyses can be separately performed in the lesion focus and penumbra with laser capture microdissection followed by polymerase chain reaction analyses. In addition, other common experimental drawbacks, such as high individual variance, are eliminated. With intraocular injections, treatments can be verified in vivo, with one eye serving as the experimental tissue and the other serving as the control tissue. In summary, we describe a flexible and easy method, which can be useful in combination with a broad variety of recently developed neuroprotective strategies, to study neurodegeneration.


Subject(s)
Eye Proteins/genetics , Neuroprotective Agents/pharmacology , Retina/cytology , Retinal Neurons/cytology , Tissue Culture Techniques , Animals , Aptamers, Nucleotide/pharmacology , Aptamers, Peptide/pharmacology , Chickens , Eye Proteins/antagonists & inhibitors , Eye Proteins/metabolism , Gene Expression , Gene Expression Profiling , Injections, Intraocular , Male , Molecular Imaging , Nanotubes , RNA, Small Interfering/genetics , Rats , Retina/drug effects , Retina/injuries , Retina/metabolism , Retinal Neurons/drug effects , Retinal Neurons/metabolism , Single-Cell Analysis
8.
PLoS One ; 7(9): e45449, 2012.
Article in English | MEDLINE | ID: mdl-23029016

ABSTRACT

Accruing evidence indicates that connexin (Cx) channels in the gap junctions (GJ) are involved in neurodegeneration after injury. However, studies using KO animal models endowed apparently contradictory results in relation to the role of coupling in neuroprotection. We analyzed the role of Cx-mediated communication in a focal lesion induced by mechanical trauma of the retina, a model that allows spatial and temporal definition of the lesion with high reproducibility, permitting visualization of the focus, penumbra and adjacent areas. Cx36 and Cx43 exhibited distinct gene expression and protein levels throughout the neurodegeneration progress. Cx36 was observed close to TUNEL-positive nuclei, revealing the presence of this protein surrounding apoptotic cells. The functional role of cell coupling was assessed employing GJ blockers and openers combined with lactate dehydrogenase (LDH) assay, a direct method for evaluating cell death/viability. Carbenoxolone (CBX), a broad-spectrum GJ blocker, reduced LDH release after 4 hours, whereas quinine, a Cx36-channel specific blocker, decreased LDH release as early as 1 hour after lesion. Furthermore, analysis of dying cell distribution confirmed that the use of GJ blockers reduced apoptosis spread. Accordingly, blockade of GJ communication during neurodegeneration with quinine, but not CBX, caused downregulation of initial and effector caspases. To summarize, we observed specific changes in Cx gene expression and protein distribution during the progress of retinal degeneration, indicating the participation of these elements in acute neurodegeneration processes. More importantly, our results revealed that direct control of GJ channels permeability may take part in reliable neuroprotection strategies aimed to rapid, fast treatment of mechanical trauma in the retina.


Subject(s)
Cell Communication/physiology , Connexins/metabolism , Neurodegenerative Diseases/etiology , Neurodegenerative Diseases/metabolism , Retina/metabolism , Retina/pathology , Wounds and Injuries/complications , Animals , Cell Communication/genetics , Chickens , Immunohistochemistry , In Situ Nick-End Labeling , Neurodegenerative Diseases/therapy , Polymerase Chain Reaction
9.
Int J Dev Neurosci ; 28(1): 39-52, 2010 Feb.
Article in English | MEDLINE | ID: mdl-19800961

ABSTRACT

Connexin (Cx) channels and hemichannels are involved in essential processes during nervous system development such as apoptosis, propagation of spontaneous activity and interkinetic nuclear movement. In the first part of this study, we extensively characterized Cx gene and protein expression during retinal histogenesis. We observed distinct spatio-temporal patterns among studied Cx and an overriding, ubiquitous presence of Cx45 in progenitor cells. The role of Cx-mediated communication was assessed by using broad-spectrum (carbenoxolone, CBX) and Cx36/Cx50 channel-specific (quinine) blockers. In vivo application of CBX, but not quinine, caused remarkable reduction in retinal thickness, suggesting changes in cell proliferation/apoptosis ratio. Indeed, we observed a decreased number of mitotic cells in CBX-injected retinas, with no significant changes in the expression of PCNA, a marker for cells in proliferative state. Taken together, our results pointed a pivotal role of Cx45 in the developing retina. Moreover, this study revealed that Cx-mediated communication is essential in retinal histogenesis, particularly in the control of cell proliferation.


Subject(s)
Cell Communication/physiology , Cell Proliferation , Connexins/metabolism , Retina/growth & development , Retina/physiology , Animals , Carbenoxolone/pharmacology , Cell Communication/drug effects , Cell Communication/genetics , Cell Proliferation/drug effects , Central Nervous System Agents/pharmacology , Connexins/antagonists & inhibitors , Connexins/genetics , Gene Expression Regulation, Developmental/drug effects , Neural Pathways/drug effects , Neural Pathways/growth & development , Neural Pathways/physiology , Neuroglia/drug effects , Neuroglia/physiology , Proliferating Cell Nuclear Antigen/metabolism , Quinine/pharmacology , Rats , Rats, Wistar , Retina/drug effects , Retinal Horizontal Cells/drug effects , Retinal Horizontal Cells/physiology , Stem Cells/drug effects , Stem Cells/physiology , Time Factors
SELECTION OF CITATIONS
SEARCH DETAIL
...