scholarly journals Cellular and molecular mechanisms of the demyelination in the central nervous system and cell therapy approaches

2017 ◽  
Vol 5 (1) ◽  
pp. 74-78
Author(s):  
V. Tsymbaliuk ◽  
V. Semenova ◽  
L. Pichkur ◽  
O. Velychko ◽  
D. Egorova

The review summarizes the current concepts of cell-tissue and molecular features of development of demyelinating processes in the central nervous system related to multiple sclerosis and its animal model – allergic encephalomyelitis. An analysis of recently published studies of this pathology, carried out with light and electron microscopy and immunohistochemical and molecular genetic methods, is given. New methodological approaches to the study of the pathomorhological aspects of demyelinating disorders allowed receiving in-depth understanding of the etiology and mechanisms of demyelination processes in the brain and spinal cord tissues at the cellular level and identifying the ways to develop effective modern methods of pathogenetic treatment of these diseases using cell therapy.

Neurosurgery ◽  
2015 ◽  
Vol 78 (3) ◽  
pp. 343-352 ◽  
Author(s):  
Arnault Tauziede-Espariat ◽  
Andre Maues de Paula ◽  
Melanie Pages ◽  
Annie Laquerriere ◽  
Emilie Caietta ◽  
...  

Abstract BACKGROUND: Primary leptomeningeal gliomatosis (PLG) is a poorly recognized tumor of the central nervous system. OBJECTIVE: To describe the histopathological, immunohistochemical, and molecular features of PLG. METHODS: Results of our multicentric retrospective study of 6 PLG cases (3 pediatric and 3 adult) were compared with literature data. RESULTS: The mean age was 54.7 years for adults and 8.7 years for children, with 3 males and 3 females. Clinical symptoms were nonspecific. Cerebrospinal fluid analyses showed a high protein level often associated with pleocytosis but without neoplastic cells. On neuroimaging, diffuse leptomeningeal enhancement and hydrocephalus were observed, except in 1 case. PLG was mostly misinterpreted as infectious or tumoral meningitis. The first biopsy was negative in 50% of cases. Histopathologically, PLG cases corresponded to 1 oligodendroglioma without 1p19q codeletion and 5 astrocytomas without expression of p53. No immunostaining for IDH1R132H and no mutations of IDH1/2 and H3F3A genes were found. Overall survival was highly variable (2-82 months) but seems to be increased in children treated with chemotherapy. CONCLUSION: This study shows the difficulties of PLG diagnosis. The challenge is to achieve an early biopsy to establish a diagnosis and to begin a treatment, but the prognosis remains poor. PLG seems to have a different molecular and immunohistochemical pattern compared with intraparenchymal malignant gliomas.


2021 ◽  
Vol 12 ◽  
Author(s):  
Mar Pacheco-Herrero ◽  
Luis O. Soto-Rojas ◽  
Charles R. Harrington ◽  
Yazmin M. Flores-Martinez ◽  
Marcos M. Villegas-Rojas ◽  
...  

The current pandemic caused by the new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become a public health emergency. To date, March 1, 2021, coronavirus disease 2019 (COVID-19) has caused about 114 million accumulated cases and 2.53 million deaths worldwide. Previous pieces of evidence suggest that SARS-CoV-2 may affect the central nervous system (CNS) and cause neurological symptoms in COVID-19 patients. It is also known that angiotensin-converting enzyme-2 (ACE2), the primary receptor for SARS-CoV-2 infection, is expressed in different brain areas and cell types. Thus, it is hypothesized that infection by this virus could generate or exacerbate neuropathological alterations. However, the molecular mechanisms that link COVID-19 disease and nerve damage are unclear. In this review, we describe the routes of SARS-CoV-2 invasion into the central nervous system. We also analyze the neuropathologic mechanisms underlying this viral infection, and their potential relationship with the neurological manifestations described in patients with COVID-19, and the appearance or exacerbation of some neurodegenerative diseases.


2021 ◽  
Vol 15 ◽  
Author(s):  
Davide Marangon ◽  
Nicolò Caporale ◽  
Marta Boccazzi ◽  
Maria P. Abbracchio ◽  
Giuseppe Testa ◽  
...  

Myelin is the lipidic insulating structure enwrapping axons and allowing fast saltatory nerve conduction. In the central nervous system, myelin sheath is the result of the complex packaging of multilamellar extensions of oligodendrocyte (OL) membranes. Before reaching myelinating capabilities, OLs undergo a very precise program of differentiation and maturation that starts from OL precursor cells (OPCs). In the last 20 years, the biology of OPCs and their behavior under pathological conditions have been studied through several experimental models. When co-cultured with neurons, OPCs undergo terminal maturation and produce myelin tracts around axons, allowing to investigate myelination in response to exogenous stimuli in a very simple in vitro system. On the other hand, in vivo models more closely reproducing some of the features of human pathophysiology enabled to assess the consequences of demyelination and the molecular mechanisms of remyelination, and they are often used to validate the effect of pharmacological agents. However, they are very complex, and not suitable for large scale drug discovery screening. Recent advances in cell reprogramming, biophysics and bioengineering have allowed impressive improvements in the methodological approaches to study brain physiology and myelination. Rat and mouse OPCs can be replaced by human OPCs obtained by induced pluripotent stem cells (iPSCs) derived from healthy or diseased individuals, thus offering unprecedented possibilities for personalized disease modeling and treatment. OPCs and neural cells can be also artificially assembled, using 3D-printed culture chambers and biomaterial scaffolds, which allow modeling cell-to-cell interactions in a highly controlled manner. Interestingly, scaffold stiffness can be adopted to reproduce the mechanosensory properties assumed by tissues in physiological or pathological conditions. Moreover, the recent development of iPSC-derived 3D brain cultures, called organoids, has made it possible to study key aspects of embryonic brain development, such as neuronal differentiation, maturation and network formation in temporal dynamics that are inaccessible to traditional in vitro cultures. Despite the huge potential of organoids, their application to myelination studies is still in its infancy. In this review, we shall summarize the novel most relevant experimental approaches and their implications for the identification of remyelinating agents for human diseases such as multiple sclerosis.


Psychiatry ◽  
2021 ◽  
Vol 19 (4) ◽  
pp. 125-134
Author(s):  
E. F. Vasilyeva ◽  
O. S. Brusov

Background: at present, the important role of the monocyte-macrophage link of immunity in the pathogenesis of mental diseases has been determined. In the first and second parts of our review, the cellular and molecular mechanisms of activation of monocytes/macrophages, which secreting proinflammatory CD16 receptors, cytokines, chemokines and receptors to them, in the development of systemic immune inflammation in the pathogenesis of somatic diseases and mental disorders, including schizophrenia, bipolar affective disorder (BAD) and depression were analyzed. The association of high levels of proinflammatory activity of monocytes/macrophages in patients with mental disorders with somatic comorbidity, including immune system diseases, is shown. It is known that proinflammatory monocytes of peripheral blood, as a result of violation of the integrity of the hematoencephalic barrier can migrate to the central nervous system and activate the resident brain cells — microglia, causing its activation. Activation of microglia can lead to the development of neuroinammation and neurodegenerative processes in the brain and, as a result, to cognitive disorders. The aim of review: to analyze the results of the main scientific studies concerning the role of cellular and molecular mechanisms of peripheral blood monocytes interaction with microglial cells and platelets in the development of neuroinflammation in the pathogenesis of mental disorders, including Alzheimer’s disease (AD). Material and methods: keywords “mental disorders, AD, proinflammatory monocytes, microglia, neuroinflammation, cytokines, chemokines, cell adhesion molecules, platelets, microvesicles” were used to search for articles of domestic and foreign authors published over the past 30 years in the databases PubMed, eLibrary, Science Direct and EMBASE. Conclusion: this review analyzes the results of studies which show that monocytes/macrophages and microglia have similar gene expression profiles in schizophrenia, BAD, depression, and AD and also perform similar functions: phagocytosis and inflammatory responses. Monocytes recruited to the central nervous system stimulate the increased production of proinflammatory cytokines IL-1, IL-6, tumor necrosis factor alpha (TNF-α), chemokines, for example, MCP-1 (Monocyte chemotactic protein-1) by microglial cells. This promotes the recruitment of microglial cells to the sites of neuronal damage, and also enhances the formation of the brain protein beta-amyloid (Aβ). The results of modern studies are presented, indicating that platelets are involved in systemic inflammatory reactions, where they interact with monocytes to form monocyte-platelet aggregates (MTA), which induce the activation of monocytes with a pro inflammatory phenotype. In the last decade, it has been established that activated platelets and other cells of the immune system, including monocytes, detached microvesicles (MV) from the membrane. It has been shown that MV are involved as messengers in the transport of biologically active lipids, cytokines, complement, and other molecules that can cause exacerbation of systemic inflammatory reactions. The presented review allows us to expand our knowledge about the cellular and molecular aspects of the interaction of monocytes/macrophages with microglial cells and platelets in the development of neuroinflammation and cognitive decline in the pathogenesis of mental diseases and in AD, and also helps in the search for specific biomarkers of the clinical severity of mental disorder in patients and the prospects for their response to treatment.


‘Neuroanatomy and neurophysiology’ covers the anatomy and organization of the central nervous system, including the skull and cervical vertebrae, the meninges, the blood and lymphatic vessels, muscles and nerves of the head and neck, and the structures of the eye, ear, and central nervous system. At a cellular level, the different cell types and the mechanism of transmission across synapses are considered, including excitatory and inhibitory synapses. This is followed by a review of the major control and sensory systems (including movement, information processing, locomotion, reflexes, and the main five senses of sight, hearing, touch, taste, and smell). The integration of these processes into higher functions (such as sleep, consciousness and coma, emotion, memory, and ageing) is discussed, along with the causes and treatments of disorders of diseases such as depression, schizophrenia, epilepsy, addiction, and degenerative diseases.


Author(s):  
Siddharthan Chandran ◽  
Alastair Compston

Clinicians suspect demyelination when episodes reflecting damage to white matter tracts within the central nervous system occur in young adults. The paucity of specific biological markers of discrete demyelinating syndromes places an emphasis on clinical phenotype—temporal and spatial patterns—when classifying demyelinating disorders. The diagnosis of multiple sclerosis, the most common demyelinating disorder, becomes probable when these symptoms and signs recur, involving different parts of the brain and spinal cord. Other important demyelinating diseases include post-infectious neurological disorders (acute disseminated encephalomyelitis), demyelination resulting from metabolic derangements (central pontine myelinosis), and inherited leucodystrophies that may present in children or in adults. Accepting differences in mechanism, presentation, and treatment, two observations can usefully be made when classifying demyelinating disorders. These are the presence or absence of inflammation, and the extent of focal vs. diffuse demyelination. Multiple sclerosis is prototypic for the former, whereas dysmyelinating disorders, such as leucodystrophies are representative of the latter....


2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Timothy M. OʼShea ◽  
Alexander L. Wollenberg ◽  
Jae H. Kim ◽  
Yan Ao ◽  
Timothy J. Deming ◽  
...  

AbstractBiomaterials hold promise for therapeutic applications in the central nervous system (CNS). Little is known about molecular factors that determine CNS foreign body responses (FBRs) in vivo, or about how such responses influence biomaterial function. Here, we probed these factors in mice using a platform of injectable hydrogels readily modified to present interfaces with different physiochemical properties to host cells. We found that biomaterial FBRs mimic specialized multicellular CNS wound responses not present in peripheral tissues, which serve to isolate damaged neural tissue and restore barrier functions. We show that the nature and intensity of CNS FBRs are determined by definable properties that significantly influence hydrogel functions, including resorption and molecular delivery when injected into healthy brain or stroke injuries. Cationic interfaces elicit stromal cell infiltration, peripherally derived inflammation, neural damage and amyloid production. Nonionic and anionic formulations show minimal levels of these responses, which contributes to superior bioactive molecular delivery. Our results identify specific molecular mechanisms that drive FBRs in the CNS and have important implications for developing effective biomaterials for CNS applications.


2020 ◽  
Vol 17 (3) ◽  
pp. 1142-1152 ◽  
Author(s):  
Karl E. Carlström ◽  
Praveen K. Chinthakindi ◽  
Belén Espinosa ◽  
Faiez Al Nimer ◽  
Elias S. J. Arnér ◽  
...  

Abstract The Nrf2 transcription factor is a key regulator of redox reactions and considered the main target for the multiple sclerosis (MS) drug dimethyl fumarate (DMF). However, exploration of additional Nrf2-activating compounds is motivated, since DMF displays significant off-target effects and has a relatively poor penetrance to the central nervous system (CNS). We de novo synthesized eight vinyl sulfone and sulfoximine compounds (CH-1–CH-8) and evaluated their capacity to activate the transcription factors Nrf2, NFκB, and HIF1 in comparison with DMF using the pTRAF platform. The novel sulfoximine CH-3 was the most promising candidate and selected for further comparison in vivo and later an experimental model for traumatic brain injury (TBI). CH-3 and DMF displayed comparable capacity to activate Nrf2 and downstream transcripts in vitro, but with less off-target effects on HIF1 from CH-3. This was verified in cultured microglia and oligodendrocytes (OLs) and subsequently in vivo in rats. Following TBI, DMF lowered the number of leukocytes in blood and also decreased axonal degeneration. CH-3 preserved or increased the number of pre-myelinating OL. While both CH-3 and DMF activated Nrf2, CH-3 showed less off-target effects and displayed more selective OL associated effects. Further studies with Nrf2-acting compounds are promising candidates to explore potential myelin protective or regenerative effects in demyelinating disorders.


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