Publications by authors named "Marracci G"

Triggering receptor expressed on myeloid cells-2 (TREM2) is a cell surface receptor on macrophages and microglia that senses and responds to disease-associated signals to regulate the phenotype of these innate immune cells. The TREM2 signaling pathway has been implicated in a variety of diseases ranging from neurodegeneration in the central nervous system to metabolic disease in the periphery. Here, we report that TREM2 is a thyroid hormone-regulated gene and its expression in macrophages and microglia is stimulated by thyroid hormone and synthetic thyroid hormone agonists (thyromimetics).

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Triggering receptor expressed on myeloid cells-2 (TREM2) is a cell surface receptor on macrophages and microglia that senses and responds to disease associated signals to regulate the phenotype of these innate immune cells. The TREM2 signaling pathway has been implicated in a variety of diseases ranging from neurodegeneration in the central nervous system to metabolic disease in the periphery. We report here that is a thyroid hormone regulated gene and its expression in macrophages and microglia is stimulated by thyroid hormone.

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We have previously demonstrated that thyromimetics stimulate oligodendrocyte precursor cell differentiation and promote remyelination in murine demyelination models. We investigated whether a thyroid receptor-beta selective thyromimetic, sobetirome (Sob), and its CNS-targeted prodrug, Sob-AM2, could prevent myelin and axonal degeneration in experimental autoimmune encephalomyelitis (EAE). Compared to controls, EAE mice receiving triiodothyronine (T3, 0.

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Background: Fast, effective, and rapid processing of central nervous system (CNS) tissue with good preservation of myelin, especially in tissue from diseased mice, is important to many laboratories studying neurosciences.

New Method: In this paper, we describe a new method to process and embed CNS tissue from mice. Spinal cords and optic nerves from naive C57BL/6 mice were used to standardize the microwave protocol following perfusion with fixative.

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Background: Lipoic acid, an antioxidant, has beneficial effects in experimental acute optic neuritis and autoimmune encephalomyelitis. Optical coherence tomography can detect retinal nerve fiber layer thinning, representing axonal degeneration, approximately 3-6 months after acute optic neuritis.

Objective: To determine whether lipoic acid is neuroprotective in acute optic neuritis.

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The anti-oxidant lipoic acid (LA) is beneficial in murine models of multiple sclerosis (MS) and has recently been shown to slow brain atrophy in secondary progressive MS. The mechanism of these effects by LA is incompletely understood but may involve effects on microglia. The objective of this study is to understand how LA affects microglial cells.

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Oligodendrocyte processes wrap axons to form neuroprotective myelin sheaths, and damage to myelin in disorders, such as multiple sclerosis (MS), leads to neurodegeneration and disability. There are currently no approved treatments for MS that stimulate myelin repair. During development, thyroid hormone (TH) promotes myelination through enhancing oligodendrocyte differentiation; however, TH itself is unsuitable as a remyelination therapy due to adverse systemic effects.

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Background: The role that dietary interventions can play in multiple sclerosis (MS) management is of huge interest amongst patients and researchers but data evaluating this is limited. Possible effects of a very-low-fat, plant-based dietary intervention on MS related progression and disease activity as measured by brain imaging and MS related symptoms have not been evaluated in a randomized-controlled trial. Despite use of disease modifying therapies (DMT), poor quality of life (QOL) in MS patients can be a significant problem with fatigue being one of the common disabling symptoms.

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Unlabelled: Multiple sclerosis is the most common chronic disabling disease in the central nervous system in young to middle aged adults. Depression is common in multiple sclerosis (MS) affecting between 50–60% of patients. Pilot studies in unipolar depression report an improvement in depression when omega-3 fatty acids are given with antidepressants.

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Cortical lesions are a crucial part of MS pathology and it is critical to determine that new MS therapies have the ability to alter cortical inflammatory lesions given the differences between white and gray matter lesions. We tested lipoic acid (LA) in a mouse focal cortical EAE model. Brain sections were stained with antibodies against CD4, CD11b and galectin-3.

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Although multiple sclerosis (MS) has traditionally been considered to be an inflammatory disease, recent evidence has brought neurodegeneration into the spotlight, suggesting that accumulated damage and loss of axons is critical to disease progression and the associated irreversible disability. Proposed mechanisms of axonal degeneration in MS posit cytosolic and subsequent mitochondrial Ca(2+) overload, accumulation of pathologic reactive oxygen species (ROS), and mitochondrial dysfunction leading to cell death. In this context, the role of the p66 isoform of ShcA protein (p66) may be significant.

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In multiple sclerosis (MS), compromised blood-brain barrier (BBB) integrity contributes to inflammatory T cell migration into the central nervous system. Matrix metalloproteinase-9 (MMP-9) is associated with BBB disruption and subsequent T cell migration into the CNS. The aim of this paper was to evaluate the effects of omega-3 fatty acids on MMP-9 levels and T cell migration.

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Objective: To describe Japanese macaque encephalomyelitis (JME), a spontaneous inflammatory demyelinating disease occurring in the Oregon National Primate Research Center's (ONPRC) colony of Japanese macaques (JMs, Macaca fuscata).

Methods: JMs with neurologic impairment were removed from the colony, evaluated, and treated with supportive care. Animals were humanely euthanized and their central nervous systems (CNSs) were examined.

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Lipoic acid (LA) is an antioxidant that is effective in treating experimental autoimmune encephalomyelitis (EAE), a model for multiple sclerosis (MS). C57BL/6 mice with EAE develop experimental autoimmune optic neuritis (EAON), which models acute optic neuritis in humans. Here we determined whether LA is therapeutically effective in EAON.

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Lipoic acid is a natural antioxidant available as an oral supplement from a number of different manufacturers. Lipoic acid administered subcutaneously is an effective therapy for murine experimental autoimmune encephalomyelitis, a model of multiple sclerosis. The aim of this study was to compare serum lipoic acid levels with oral dosing in patients with multiple sclerosis with serum levels in mice receiving subcutaneous doses of lipoic acid.

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Objectives: The primary objective was to evaluate the effect of omega-3 fatty acids (omega-3 FA) on matrix metalloproteinase-9 (MMP-9) production by immune cells in multiple sclerosis (MS). Quality of life, fatty acid levels, and safety were also evaluated.

Materials And Methods: Ten participants with relapsing-remitting MS (RRMS) received omega-3 FA supplementation (9.

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The antioxidant lipoic acid (LA) treats and prevents the animal model of multiple sclerosis (MS), experimental autoimmune encephalomyelitis (EAE). In an effort to understand the therapeutic potential of LA in MS, we sought to define the cellular mechanisms that mediate the effects of LA on human natural killer (NK) cells, which are important in innate immunity as the first line of defense against invading pathogens and tumor cells. We discovered that LA stimulates cAMP production in NK cells in a dose-dependent manner.

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Multiple sclerosis (MS) is the leading cause of neurological disability in young adults, affecting some two million people worldwide. Traditionally, MS has been considered a chronic, inflammatory disorder of the central white matter in which ensuing demyelination results in physical disability [Frohman EM, Racke MK, Raine CS (2006) N Engl J Med 354:942-955]. More recently, MS has become increasingly viewed as a neurodegenerative disorder in which neuronal loss, axonal injury, and atrophy of the CNS lead to permanent neurological and clinical disability.

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The anti-oxidant lipoic acid (LA) potently suppresses clinical and pathologic disease in the animal model of multiple sclerosis, experimental autoimmune encephalomyelitis, by inhibiting the migration of pathogenic T cells to the spinal cord. The mechanism by which this occurs is largely unknown. In this report we demonstrate that LA induces increases in cyclic AMP, a known immunosuppressant, in human T cells.

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Lipoic acid (LA) suppresses and treats murine experimental autoimmune encephalomyelitis (EAE), which models multiple sclerosis. However, the mechanisms by which LA mediates its effects in EAE are only partially known. In the present study, LA (25, 50 and 100 microg/ml) inhibited upregulation of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in tumor necrosis factor-alpha (TNF-alpha) stimulated cultured brain endothelial cells.

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Lipoic acid is an antioxidant that suppresses and treats a model of multiple sclerosis, experimental autoimmune encephalomyelitis. We now demonstrate that treatment of human PBMC and T cell lines with LA downmodulated CD4 expression in a concentration-dependent manner. LA treatment of Con A stimulated PBMC specifically removed CD4 from the T-cell surface, but not CD3.

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Lipoic acid (LA) is an antioxidant that suppresses and treats an animal model of multiple sclerosis (MS), experimental autoimmune encephalomyelitis. The purpose of this study was to determine the pharmacokinetics (PK), tolerability and effects on matrix metalloproteinase-9 (MMP-9) and soluble intercellular adhesion molecule-1 (sICAMP-1) of oral LA in patients with MS. Thirty-seven MS subjects were randomly assigned to one of four groups: placebo, LA 600 mg twice a day, LA 1200 mg once a day and LA 1200 mg twice a day.

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We have demonstrated previously the ability of the antioxidant alpha lipoic acid (ALA) to suppress and treat a model of multiple sclerosis (MS), relapsing experimental autoimmune encephalomyelitis (EAE). We describe the effects of ALA and its reduced form, dihydrolipoic acid (DHLA), on the transmigration of human Jurkat T cells across a fibronectin barrier in a transwell system. ALA and DHLA inhibited migration of Jurkat cells in a dose-dependent fashion by 16-75%.

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Oxidative injury may be important to the pathogenesis of multiple sclerosis (MS). We tested the antioxidant alpha lipoic acid (ALA) in an experimental murine model of MS, experimental autoimmune encephalomyelitis (EAE). ALA was administered to SJL mice 7 days after immunization with proteolipid protein (PLP) 139-151 peptide.

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The simian retrovirus (SRV) genome contains a constitutive transport element (CTE) within its 3' intergenic region (IR) that mediates the nuclear export of unspliced SRV RNA. The serogroup 2 SRV CTE is predicted to form a stable stem-loop structure containing two major internal loops exhibiting 180 degrees inverse symmetry, with loop face sequences A, A', B, and B' and additional minor internal and terminal loops. To begin the identification of potential CTE-interacting proteins and to assess structural requirements for protein interaction, we conducted RNA mobility shift assays using IR fragments that obliterated this region's known stable stem-loop structure.

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