Search results for "myelination"

2013

In the central nervous system (CNS) of most vertebrates, oligodendrocytes enwrap neuronal axons with extensions of their plasma membrane to form the myelin sheath. Several proteins are characteristically found in myelin of which Myelin Basic Protein (MBP) is the second most abundant one after Proteolipid Protein (PLP). The lack of functional MBP in rodents results in a severe hypomyelinated phenotype in the CNS demonstrating its importance for myelin synthesis. Mbp mRNA is transported from the nucleus to the plasma membrane and is translated locally at the axon-glial contact site. Axonal properties such as diameter or electrical activity influence the degree of myelination. As oligodendrocy…

Potential Biomarkers Associated with Multiple Sclerosis Pathology

2021

Multiple sclerosis (MS) is a complex disease of the central nervous system (CNS) that involves an intricate and aberrant interaction of immune cells leading to inflammation, demyelination, and neurodegeneration. Due to the heterogeneity of clinical subtypes, their diagnosis becomes challenging and the best treatment cannot be easily provided to patients. Biomarkers have been used to simplify the diagnosis and prognosis of MS, as well as to evaluate the results of clinical treatments. In recent years, research on biomarkers has advanced rapidly due to their ability to be easily and promptly measured, their specificity, and their reproducibility. Biomarkers are classified into several categor…

Axon-glia interaction and membrane traffic in myelin formation

2014

In vertebrate nervous systems myelination of neuronal axons has evolved to increase conduction velocity of electrical impulses with minimal space and energy requirements. Myelin is formed by specialized glial cells which ensheath axons with a lipid-rich insulating membrane. Myelination is a multi-step process initiated by axon-glia recognition triggering glial polarization followed by targeted myelin membrane expansion and compaction. Thereby, a myelin sheath of complex subdomain structure is established. Continuous communication between neurons and glial cells is essential for myelin maintenance and axonal integrity. A diverse group of diseases, from multiple sclerosis to schizophrenia, ha…

The experimental antiphospholipid syndrome: an invaluable tool to study autoimmunity-induced neurodegeneration

2014

cells and its activation inhibits their differentiation and remyelination. These suggest a possible role of CNS TLR2 in progressive autoimmune demyelination. Methods: We examined the effects of intra-cerebro-ventricular (ICV) injection of Zymozan, a TLR2 agonist, on the clinical and pathological course of EAE. The survival and clinical scores were monitored; demyelination and axonal loss were quantified by gold-black and Bielschowsky stains, and the nature of neuro-inflammatory response was characterized by TLR2, IBA-1 and CD3 stainings and PCR for immune cytokines. Immune cells were isolated from EAE brain tissue and their proliferative response to the autoantigen (PLP peptide) or Concaval…

Is Oxidative Stress the Link Between Cerebral Small Vessel Disease, Sleep Disruption, and Oligodendrocyte Dysfunction in the Onset of Alzheimer’s Dis…

2021

Oxidative stress is an early occurrence in the development of Alzheimer’s disease (AD) and one of its proposed etiologic hypotheses. There is sufficient experimental evidence supporting the theory that impaired antioxidant enzymatic activity and increased formation of reactive oxygen species (ROS) take place in this disease. However, the antioxidant treatments fail to stop its advancement. Its multifactorial condition and the diverse toxicological cascades that can be initiated by ROS could possibly explain this failure. Recently, it has been suggested that cerebral small vessel disease (CSVD) contributes to the onset of AD. Oxidative stress is a central hallmark of CSVD and is depicted as …

Heat Shock Proteins in Multiple Sclerosis Pathogenesis: Friend or Foe?

2015

Multiple Sclerosis is a complex chronic inflammatory, neurodegenerative disease conditioned by genetic, epigenetic and environmental factors. Main pathological features of MS include areas of focal demyelination of white matter characterized by gliosis, neuron and oligodendrocyte loss. Neurodegenerative as well as immune-mediated processes play a role in the pathogenesis of this disease. One of these immunogenic factors could be represented by the heat shock proteins. HSP exhibit cytoprotective and cytostimulatory effects due to their molecular chaperones role, in many brain model misfolding diseases such as Alzheimer’s and Parkinson’s diseases, whereas still no unambiguous results have bee…

Linking immune-mediated damage to neurodegeneration in multiple sclerosis: could network-based MRI help?

2021

Abstract Inflammatory demyelination characterizes the initial stages of multiple sclerosis, while progressive axonal and neuronal loss are coexisting and significantly contribute to the long-term physical and cognitive impairment. There is an unmet need for a conceptual shift from a dualistic view of multiple sclerosis pathology, involving either inflammatory demyelination or neurodegeneration, to integrative dynamic models of brain reorganization, where, glia-neuron interactions, synaptic alterations and grey matter pathology are longitudinally envisaged at the whole-brain level. Functional and structural MRI can delineate network hallmarks for relapses, remissions or disease progression, …

Development of Bioimage Analysis tools for the study of neurogenesis and neurodegeneration

2021

ANTECEDENTES La combinación sinérgica de métodos automatizados de captura y análisis de bioimagen está emergiendo como un enfoque de vanguardia para abordar muchas cuestiones biológicas. Sin embargo, hay muchos campos en los que estas técnicas aún no se implementan y, en cambio, todavía se basan en la inspección visual y el análisis manual, que inevitablemente limitan el rendimiento alcanzable y son más propensos a introducir el sesgo del investigador. Por lo tanto, aún queda un gran esfuerzo por hacer en la difusión del uso de tecnologías de bioimagen de vanguardia en los campos de las ciencias de la vida con una gran dependencia de métodos de microscopía. En la presente tesis, nuestro obj…