scholarly journals Regulation of Oligodendrocyte Functions: Targeting Lipid Metabolism and Extracellular Matrix for Myelin Repair

2020 ◽  
Vol 9 (2) ◽  
pp. 470 ◽  
Author(s):  
Davide Marangon ◽  
Marta Boccazzi ◽  
Davide Lecca ◽  
Marta Fumagalli

Myelin is an essential structure that protects axons, provides metabolic support to neurons and allows fast nerve transmission. Several neurological diseases, such as multiple sclerosis, are characterized by myelin damage, which is responsible of severe functional impairment. Myelin repair requires the timely recruitment of adult oligodendrocyte precursor cells (OPCs) at the lesion sites, their differentiation and maturation into myelinating oligodendrocytes. As a consequence, OPCs undergo profound changes in their morphology, functions, and interactions with other cells and extracellular environment, thus requiring the reorganization of both their lipid metabolism and their membrane composition, which is substantially different compared to other plasma membranes. Despite the growing knowledge in oligodendroglia biology and in the mechanisms involved in OPC-mediated regeneration, the identification of strategies to promote remyelination still remains a challenge. Here, we describe how altered lipid metabolism in oligodendrocytes influences the pathogenesis of demyelination, and we show that several FDA-approved drugs with a previously unknown remyelination potential do act on cholesterol and lipid biosynthetic pathways. Since the interplay between myelin lipids and axons is strictly coordinated by the extracellular matrix (ECM), we also discuss the role of different ECM components, and report the last findings on new ECM-modifiers able to foster endogenous remyelination.

2021 ◽  
Vol 12 ◽  
Author(s):  
Carlos Noe Farfan-Morales ◽  
Carlos Daniel Cordero-Rivera ◽  
José Manuel Reyes-Ruiz ◽  
Arianna M. Hurtado-Monzón ◽  
Juan Fidel Osuna-Ramos ◽  
...  

Although Flaviviruses such as dengue (DENV) and zika (ZIKV) virus are important human pathogens, an effective vaccine or antiviral treatment against them is not available. Hence, the search for new strategies to control flavivirus infections is essential. Several studies have shown that the host lipid metabolism could be an antiviral target because cholesterol and other lipids are required during the replicative cycle of different Flaviviridae family members. FDA-approved drugs with hypolipidemic effects could be an alternative for treating flavivirus infections. However, a better understanding of the regulation between host lipid metabolism and signaling pathways triggered during these infections is required. The metabolic pathways related to lipid metabolism modified during DENV and ZIKV infection are analyzed in this review. Additionally, the role of lipid-lowering drugs as safe host-targeted antivirals is discussed.


4open ◽  
2019 ◽  
Vol 2 ◽  
pp. 11 ◽  
Author(s):  
Björn L.D.M. Brücher ◽  
Ijaz S. Jamall

Fibroblasts are actively involved in the creation of the stroma and the extracellular matrix which are important for cell adhesion, cell–cell communication, and tissue metabolism. The role of fibrosis in carcinogenesis can be examined by analogy to tissues of various cancers. The orchestration of letters in the interplay of manifold components with signaling and crosstalk is incompletely understood but available evidence suggests a hitherto underappreciated role for fibrosis in carcinogenesis. Complex signaling and crosstalk by pathogenic stimuli evoke persistent subclinical inflammation, which in turn, results in a cascade of different cell types, ubiquitous proteins and their corresponding enzymes, cytokine releases, and multiple signaling pathways promoting the onset of fibrosis. There is considerable evidence that the body's attempt to resolve such a modified extracellular environment leads to further disruption of homeostasis and the genesis of the precancerous niche as part of the six-step process that describes carcinogenesis. The precancerous niche is formed and can be understood to develop as a result of (1) pathogenic stimulus, (2) chronic inflammation, and (3) fibrosis with alterations of the extracellular matrix, stromal rigidity, and mechano-transduction. This is why carcinogenesis is not just a process of aberrant cell growth with damaged genetic material but the role of the PCN in its entirety reveals how carcinogenesis can occur without invoking the need for somatic mutations.


2021 ◽  
Vol 2 ◽  
Author(s):  
Vui King Vincent-Chong ◽  
Mukund Seshadri

Head and neck squamous cell carcinomas (HNSCC) are loco-regionally aggressive tumors that often lead to debilitating changes in appearance, speech, swallowing and respiratory function in patients. It is therefore critical to develop novel targeted treatment strategies that can effectively target multiple components within the tumor microenvironment. In this regard, there has been an increased recognition of the role of neural signaling networks as mediators of disease progression in HNSCC. Here, we summarize the current knowledge on the mechanisms of adrenergic signaling in HNSCC specifically focusing on neurovascular crosstalk and the potential of targeting the adrenergic-angiogenic axis through repurposing of FDA-approved drugs against HNSCC.


Neurosurgery ◽  
2017 ◽  
Vol 64 (CN_suppl_1) ◽  
pp. 242-242 ◽  
Author(s):  
Jason K Karimy ◽  
Jinwei Zhang ◽  
David B Kurland ◽  
Brianna Carusillo Theriault ◽  
Daniel Duran ◽  
...  

Abstract INTRODUCTION Intraventricular hemorrhage (IVH) frequently causes post-hemorrhagic hydrocephalus (PHH) as a result of impaired cerebrospinal fluid (CSF) homeostasis. The most common treatment for PHH is surgical CSF shunting, a procedure fraught with complications. Historically, it is thought that PHH results from impaired reabsorption of CSF, however, little consideration has been given to the role of CSF hypersecretion. Recently, toll-like receptor-4 (TLR-4) has been implicated in the CNS by detecting “alarmins”, including IVH-derived metabolites, via recognition of damage-associated molecular patterns. We speculate that IVH triggers TLR-4-dependent inflammation at the choroid plexus epithelia (CPE), leading to CSF hypersecretion contributing to the development of PHH. METHODS In an established rat model of IVH, we assessed the rate of CSF secretion, CPE inflammation and the effect of genetic and pharmacological intervention on the development of PHH. We developed and implemented a novel surgical method in rats to measure the rate of CSF secretion. TLR-4 knockout rats, antisense oligodeoxynucleotide-mediated gene knockdown, and intracerebroventricular delivery of FDA-approved drugs were used to assess the role of specific inflammatory and ion transport targets on CSF secretion rate and ventriculomegaly following IVH. Immunoblot and immunohistochemistry were used to detect and quantify inflammatory markers. RESULTS >We show IVH triggers TLR4-NFkB-mediated inflammation at the CPE that is associated with a striking ∼3-fold increase in CSF secretion sufficient to cause PHH. CSF hypersecretion is dependent on the NFkB-regulated kinase SPAK, which interacts with and phosphorylates the bumetanide-sensitive NKCC1 at the CPE apical membrane. Genetic ablation of TLR-4 or SPAK, and pharmacology antagonizing TLR-4-NFkB signaling or the SPAK-NKCC1 complex normalizes CSF secretion rates and ventriculomegaly after IVH. CONCLUSION These data uncover a previously unrecognized role for CSF hypersecretion in the pathogenesis of PHH, and reveal a novel TLR-4-dependent regulatory pathway of CSF secretion that can be targeted with repurposed, FDA-approved drugs for the non-surgical treatment of PHH.


Biomedicines ◽  
2021 ◽  
Vol 9 (11) ◽  
pp. 1667
Author(s):  
Mansoureh Barzegar ◽  
Karen Y. Stokes ◽  
Oleg Chernyshev ◽  
Roger E. Kelley ◽  
Jonathan S. Alexander

Ischemic stroke remains the leading cause of neurologically based morbidity and mortality. Current stroke treatment is limited to two classes of FDA-approved drugs: thrombolytic agents (tissue plasminogen activator (tPA)) and antithrombotic agents (aspirin and heparin), which have a narrow time-window (<4.5 h) for administration after onset of stroke symptoms. While thrombolytic agents restore perfusion, they carry serious risks for hemorrhage, and do not influence damage responses during reperfusion. Consequently, stroke therapies that can suppress deleterious effects of ischemic injury are desperately needed. Angiotensin converting enzyme-2 (ACE2) has been recently suggested to beneficially influence experimental stroke outcomes by converting the vasoconstrictor Ang II into the vasodilator Ang 1–7. In this review, we extensively discuss the protective functions of ACE2-Ang (1–7)-MasR axis of renin angiotensin system (RAS) in ischemic stroke.


2014 ◽  
Vol 58 (11) ◽  
pp. 6508-6517 ◽  
Author(s):  
Uyen T. Nguyen ◽  
Hanjeong Harvey ◽  
Andrew J. Hogan ◽  
Alexandria C. F. Afonso ◽  
Gerard D. Wright ◽  
...  

ABSTRACTDisinfectant-tolerantListeria monocytogenesbiofilms can colonize surfaces that come into contact with food, leading to contamination and, potentially, food-borne illnesses. To better understand the process ofL. monocytogenesbiofilm formation and dispersal, we screened 1,120 off-patent FDA-approved drugs and identified several that modulateListeriabiofilm development. Among the hits were more than 30 β-lactam antibiotics, with effects ranging from inhibiting (≤50%) to stimulating (≥200%) biofilm formation compared to control. Most β-lactams also dispersed a substantial proportion of established biofilms. This phenotype did not necessarily involve killing, as >50% dispersal could be achieved with concentrations as low as 1/20 of the MIC of some cephalosporins. Penicillin-binding protein (PBP) profiling using a fluorescent penicillin analogue showed similar inhibition patterns for most β-lactams, except that biofilm-stimulatory drugs did not bind PBPD1, a low-molecular-weightd,d-carboxypeptidase. Compared to the wild type, apbpD1mutant had an attenuated biofilm response to stimulatory β-lactams. The cephalosporin-responsive CesRK two-component regulatory system, whose regulon includes PBPs, was not required for the response. The requirement for PBPD1 activity for β-lactam stimulation ofL. monocytogenesbiofilms shows that the specific set of PBPs that are inactivated by a particular drug dictates whether a protective biofilm response is provoked.


Author(s):  
Lenin Andres Gonzalez Paz ◽  
Carla A. Lossada ◽  
Luis S. Moncayo ◽  
Freddy Romero ◽  
J. L. Paz ◽  
...  

The global pandemic caused by the new SARS-COV-2 coronavirus makes it necessary to search for drugs for its control. Within of this research it has been known that the ivermectin drug, a FDA-approved drugs which is formulated as an 80:20 mixture of ivermectin B1a and B1b and used commonly for parasitic infections, has an inhibitory effect on viruses, includes SARS-COV-2 at in vitro level. In the particular case of SARS-COV-2 its mechanism of action remains elusive and controversial. Interestingly, the energy of interaction of ivermectin with any of the proteins the SARS-CoV-2 and the possible structural alterations at the protein level that this drug can cause have not been reported. In this sense, we carried out a bioinformatics study with docking strategies and molecular dynamics to predict the binding and disturbance induced by ivermectin in proteins associated with SARS-CoV-2. We use DockThor and Molegro docking scores. The DockThor server and myPresto software were used to build complexes and dynamics studies, respectively. The results obtained suggested that ivermectin is capable of docking with the 3CL protease and the HR2 domain, and may promote structural changes in these proteins by inducing unfolding/folding. Specifically, ivermectin brings protease to a significantly more deployed conformational state and the HR2 domain to a more compact state compared to the native state. Finally, it is shown that B1a and B1b macrocyclic lactones have a behavior different from to each target protein. These results suggest a possible inhibitory effect against SARS-CoV-2 due to a synergistic role of this drug to spontaneously bind to two important proteins involve in the proliferation of this virus. However, more studies are required on this possible mechanism of action.


2020 ◽  
Author(s):  
Cassandra Batzlaff Braun ◽  
Megan Girtman ◽  
Paige Jenson ◽  
Michael H Bourne ◽  
JuneMee Chae ◽  
...  

AbstractAimsSuccessful management of IPF will likely require multi-drug therapy as its pathogenesis is thought to be both driven by both pro-inflammatory and pro-fibrotic pathways. We hypothesized that the available anti-fibrotic agents, pirfenidone and nintedanib, may exhibit synergy in suppressing lung fibroblast extracellular matrix protein generation when administered in combination with other orally active agents.Materials and MethodsA fibroblastic cell line (AKR-2B) was stimulated with TGF-β1 and used to screen a library of over 1500 FDA approved drugs. Extracellular matrix protein generation was assessed via fibronectin ELISA assay and maintenance of cell viability confirmed with XTT assay.ResultsThe screening revealed sixty-two drugs from the repurposed drug-screening library that were shown to significantly suppress fibronectin expression and not result in cell death. Specifically drugs within the category of NSAIDs, steroids, azole antifungal agents, and antipyrine were associated with significant suppression of fibronectin on ELISA analysis. Surprisingly, we observed anti-fibrotic activity across a number of the azole antifungal compounds. We next assessed whether combination of azoles would exhibit synergy when combined with current anti-fibrotic therapies in the stimulated fibroblasts. As proof of concept, we demonstrated in vitro synergy between oxiconazole and nintedanib in suppressing fibroblast generation of extracellular matrix fibronectin.ConclusionsThese results suggest an approach to identify potential combinations of therapy that may improve patient outcomes by reducing cost and potential toxicities during treatment.


Cancers ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 615 ◽  
Author(s):  
Rafael Peláez ◽  
Ana Pariente ◽  
Álvaro Pérez-Sala ◽  
Ignacio M. Larrayoz

Invadopodia are actin-rich protrusions developed by transformed cells in 2D/3D environments that are implicated in extracellular matrix (ECM) remodeling and degradation. These structures have an undoubted association with cancer invasion and metastasis because invadopodium formation in vivo is a key step for intra/extravasation of tumor cells. Invadopodia are closely related to other actin-rich structures known as podosomes, which are typical structures of normal cells necessary for different physiological processes during development and organogenesis. Invadopodia and podosomes are included in the general term ‘invadosomes,’ as they both appear as actin puncta on plasma membranes next to extracellular matrix metalloproteinases, although organization, regulation, and function are slightly different. Integrins are transmembrane proteins implicated in cell–cell and cell–matrix interactions and other important processes such as molecular signaling, mechano-transduction, and cell functions, e.g., adhesion, migration, or invasion. It is noteworthy that integrin expression is altered in many tumors, and other pathologies such as cardiovascular or immune dysfunctions. Over the last few years, growing evidence has suggested a role of integrins in the formation of invadopodia. However, their implication in invadopodia formation and adhesion to the ECM is still not well known. This review focuses on the role of integrins in invadopodium formation and provides a general overview of the involvement of these proteins in the mechanisms of metastasis, taking into account classic research through to the latest and most advanced work in the field.


2019 ◽  
Vol 47 (5) ◽  
pp. 1543-1555 ◽  
Author(s):  
Maurizio Mongiat ◽  
Simone Buraschi ◽  
Eva Andreuzzi ◽  
Thomas Neill ◽  
Renato V. Iozzo

Abstract The extracellular matrix is a network of secreted macromolecules that provides a harmonious meshwork for the growth and homeostatic development of organisms. It conveys multiple signaling cascades affecting specific surface receptors that impact cell behavior. During cancer growth, this bioactive meshwork is remodeled and enriched in newly formed blood vessels, which provide nutrients and oxygen to the growing tumor cells. Remodeling of the tumor microenvironment leads to the formation of bioactive fragments that may have a distinct function from their parent molecules, and the balance among these factors directly influence cell viability and metastatic progression. Indeed, the matrix acts as a gatekeeper by regulating the access of cancer cells to nutrients. Here, we will critically evaluate the role of selected matrix constituents in regulating tumor angiogenesis and provide up-to-date information concerning their primary mechanisms of action.


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