Efficacy and tolerability of folate-aminopterin therapy in a rat focal model of multiple sclerosis

Abstract Background Activated macrophages in the experimental model of multiple sclerosis (MS) express folate receptor-β (FR-β), representing a promising target for the treatment of MS. Here, we both evaluated the efficacy of a novel folate-aminopterin construct (EC2319) in a rat focal model of multiple sclerosis (MS) and investigated the utility of 68Ga-labeled 1,4,7-triazacyclononane-1,4,7-triacetic acid-conjugated folate (68Ga-FOL) for assessing inflammatory lesions. In addition, we investigated whether FR-β is expressed in the brain of patients with MS. Methods Focal delayed-type hypersensitivity experimental autoimmune encephalomyelitis (fDTH-EAE) was induced in 40 Lewis rats; 20 healthy Lewis rats were used as controls. Rats were divided into six groups according to the duration of disease (control, acute, or chronic) and intervention (vehicle versus EC2319). 68Ga-FOL analyses, histology, and immunofluorescence of the brain were performed to evaluate the efficacy of subcutaneously administered EC2319 on lesion development. Immunofluorescence was used to assess FR-β expression in postmortem brain samples from 5 patients with MS and 5 healthy controls. Results Immunofluorescence and histological analyses revealed significant reductions in FR-β expression (P < 0.05) and lesion size (P < 0.01), as well as improved inducible nitric oxide synthase/mannose receptor C type 1 ratios (P < 0.01) in macrophages and microglia during the chronic but not acute phase of fDTH-EAE in EC2319-treated rats. The uptake of IV-injected 68Ga-FOL in the brain was low and did not differ between the groups, but the in vitro binding of 68Ga-FOL was significantly lower in EC2319-treated rats (P < 0.01). FR-β positivity was observed in chronically active lesions and in normal-appearing white matter in MS brain samples. Conclusions EC2319 was well tolerated and attenuated inflammation and lesion development in a rat model of a chronic progressive form of MS. Human MS patients have FR-β-positive cells in chronically active plaques, which suggests that these results may have translational relevance.

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TBK1 interacts with tau and enhances neurodegeneration in tauopathy

10.1101/2020.06.17.157552 ◽

2020 ◽

Author(s):

Measho H. Abreha ◽

Shamsideen Ojelade ◽

Eric B. Dammer ◽

Zachary T. McEachin ◽

Duc M. Duong ◽

...

Keyword(s):

Neuronal Loss ◽

Postmortem Brain ◽

Chromosome 17 ◽

Phosphorylation Sites ◽

Tau Hyperphosphorylation ◽

Reciprocal Effect ◽

Full Complement ◽

The Brain ◽

Brain Tissues

ABSTRACTOne of the defining pathological features of Alzheimer’s Disease (AD) is the deposition of neurofibrillary tangles (NFTs) composed of hyperphosphorylated tau in the brain. Aberrant activation of kinases in AD has been suggested to enhance phosphorylation and toxicity of tau, making the responsible tau-directed kinases attractive therapeutic targets. The full complement of tau interacting kinases in AD brain and their activity in disease remains incompletely defined. Here, immunoaffinity enrichment coupled with mass spectrometry (MS) identified TANK-binding kinase 1 (TBK1) as a tau-interacting partner in human AD cortical brain tissues. We validated this interaction in both human AD and familial frontotemporal dementia and parkinsonism linked to chromosome 17 (FTDP-17) caused by mutations in MAPT (R406W) postmortem brain tissues as well as human cell lines. Further, we document increased TBK1 activity in both AD and FTDP-17 and map the predominant TBK1 phosphorylation sites on tau based on in vitro kinase assays coupled to MS. Lastly, in a Drosophila tauopathy model, activating expression of a conserved TBK1 ortholog triggers tau hyperphosphorylation and enhanced neurodegeneration, whereas knockdown had the reciprocal effect, suppressing tau toxicity. Collectively, our findings suggest that increased TBK1 activity may promote tau hyperphosphorylation and neuronal loss in AD and related tauopathies.

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An argument for broad use of high efficacy treatments in early multiple sclerosis

Neurology Neuroimmunology & Neuroinflammation ◽

10.1212/nxi.0000000000000636 ◽

2019 ◽

Vol 7 (1) ◽

pp. e636 ◽

Cited By ~ 6

Author(s):

James M. Stankiewicz ◽

Howard L. Weiner

Keyword(s):

Multiple Sclerosis ◽

Treatment Approach ◽

Disease Course ◽

Long Term Outcomes ◽

The Past ◽

Recent Developments ◽

The Brain

Two different treatment paradigms are most often used in multiple sclerosis (MS). An escalation or induction approach is considered when treating a patient early in the disease course. An escalator prioritizes safety, whereas an inducer would favor efficacy. Our understanding of MS pathophysiology has evolved with novel in vivo and in vitro observations. The treatment landscape has also shifted significantly with the approval of over 10 new medications over the past decade alone. Here, we re-examine the treatment approach in light of these recent developments. We believe that recent work suggests that early prediction of the disease course is fraught, the amount of damage to the brain that MS causes is underappreciated, and its impact on patient function oftentimes is underestimated. These concerns, coupled with the recent availability of agents that allow a better therapeutic effect without compromising safety, lead us to believe that initiating higher efficacy treatments early is the best way to achieve the best possible long-term outcomes for people with MS.

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Splenic autonomic denervation increases inflammatory status but does not aggravate atherosclerotic lesion development

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00787.2014 ◽

2015 ◽

Vol 309 (4) ◽

pp. H646-H654 ◽

Cited By ~ 15

Author(s):

Sander Kooijman ◽

Illiana Meurs ◽

Lianne van Beek ◽

P. Padmini S. J. Khedoe ◽

Annabel Giezekamp ◽

...

Keyword(s):

Proinflammatory Cytokines ◽

Atherosclerotic Lesion ◽

Lesion Size ◽

Lesion Development ◽

Inflammatory Status ◽

Sham Surgery ◽

Peritoneal Leukocytes ◽

Leukocyte Counts ◽

The Brain ◽

Atherosclerotic Lesion Development

The brain plays a prominent role in the regulation of inflammation. Immune cells are under control of the so-called cholinergic anti-inflammatory reflex, mainly acting via autonomic innervation of the spleen. Activation of this reflex inhibits the secretion of proinflammatory cytokines and may reduce the development of atherosclerosis. Therefore, the aim of this study was to evaluate the effects of selective parasympathetic (Px) and sympathetic (Sx) denervation of the spleen on inflammatory status and atherosclerotic lesion development. Female APOE*3-Leiden.CETP mice, a well-established model for human-like lipid metabolism and atherosclerosis, were fed a cholesterol-containing Western-type diet for 4 wk after which they were subdivided into three groups receiving either splenic Px, splenic Sx, or sham surgery. The mice were subsequently challenged with the same diet for an additional 15 wk. Selective Px increased leukocyte counts (i.e., dendritic cells, B cells, and T cells) in the spleen and increased gene expression of proinflammatory cytokines in the liver and peritoneal leukocytes compared with Sx and sham surgery. Both Px and Sx increased circulating proinflammatory cytokines IL-1β and IL-6. However, the increased proinflammatory status in denervated mice did not affect atherosclerotic lesion size or lesion composition. Conclusion: Predominantly selective Px of the spleen enhances the inflammatory status, which, however, does not aggravate diet-induced atherosclerotic lesion development.

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Multiple Sclerosis CD49d+CD154+ As Myelin-Specific Lymphocytes Induced During Remyelination

Cells ◽

10.3390/cells9010015 ◽

2019 ◽

Vol 9 (1) ◽

pp. 15

Author(s):

Paweł Piatek ◽

Magdalena Namiecinska ◽

Małgorzata Domowicz ◽

Marek Wieczorek ◽

Sylwia Michlewska ◽

...

Keyword(s):

Multiple Sclerosis ◽

Cumulative Effect ◽

Autoimmune Encephalomyelitis ◽

The Central Nervous System ◽

Cns Demyelination ◽

The Brain ◽

Experimental Autoimmune

Multiple sclerosis (MS) is a demyelinating autoimmune disease of the central nervous system (CNS) mediated by autoreactive lymphocytes. The role of autoreactive lymphocytes in the CNS demyelination is well described, whereas very little is known about their role in remyelination during MS remission. In this study, we identified a new subpopulation of myelin-specific CD49d+CD154+ lymphocytes presented in the peripheral blood of MS patients during remission, that proliferated in vitro in response to myelin peptides. These lymphocytes possessed the unique ability to migrate towards maturing oligodendrocyte precursor cells (OPCs) and synthetize proinflammatory chemokines/cytokines. The co-culture of maturing OPCs with myelin-specific CD49d+CD154+ lymphocytes was characterized by the increase in proinflammatory chemokine/cytokine secretion that was not only a result of their cumulative effect of what OPCs and CD49d+CD154+ lymphocytes produced alone. Moreover, maturing OPCs exposed to exogenous myelin peptides managed to induce CD40-CD154-dependent CD49d+CD154+ lymphocyte proliferation. We confirmed, in vivo, the presence of CD49d+CD154+ cells close to maturating OPCs and remyelinating plaque during disease remission in the MS mouse model (C57Bl/6 mice immunized with MOG35-55) by immunohistochemistry. Three weeks after an acute phase of experimental autoimmune encephalomyelitis, CD49d+/CD154+ cells were found to be co-localized with O4+ cells (oligodendrocyte progenitors) in the areas of remyelination identified by myelin basic protein (MBP) labelling. These data suggested that myelin-specific CD49d+CD154+ lymphocytes present in the brain can interfere with remyelination mediated by oligodendrocytes probably as a result of establishing proinflammatory environment.

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Differential expression of multiple kallikreins in a viral model of multiple sclerosis points to unique roles in the innate and adaptive immune response

Biological Chemistry ◽

10.1515/hsz-2014-0141 ◽

2014 ◽

Vol 395 (9) ◽

pp. 1063-1073 ◽

Cited By ~ 13

Author(s):

Michael Panos ◽

George P. Christophi ◽

Moses Rodriguez ◽

Isobel A. Scarisbrick

Keyword(s):

Multiple Sclerosis ◽

Spinal Cord ◽

Immune Response ◽

Demyelinating Disease ◽

Adaptive Immune Response ◽

Innate Immune ◽

Axon Degeneration ◽

Functional Link ◽

The Brain

Abstract Recent studies provide a functional link between kallikrein 6 (Klk6) and the development and progression of disease in patients with multiple sclerosis (MS) and in its murine models. To evaluate the involvement of additional kallikrein family members, we compared Klk6 expression with four other kallikreins (Klk1, Klk7, Klk8, and Klk10) in the brain and spinal cord of mice infected with Theiler’s murine encephalomyelitis virus, an experimental model of progressive MS. The robust upregulation of Klk6 and Klk8 in the brain during the acute phase of viral encephalitis and in the spinal cord during disease development and progression points to their participation in inflammation, demyelination, and progressive axon degeneration. More limited changes in Klk1, Klk7, and Klk10 were also observed. In addition, Klk1, Klk6, and Klk10 were dynamically regulated in T cells in vitro as a recall response to viral antigen and in activated monocytes, pointing to their activities in the development of adaptive and innate immune function. Together, these results point to overlapping and unique roles for multiple kallikreins in the development and progression of virus-mediated central nervous system inflammatory demyelinating disease, including activities in the development of the adaptive and innate immune response, in demyelination, and in progressive axon degeneration.

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Influence of Metal Ions on Microtubules as a Possible Mechanism of Pathogenesis of Alzheimer′s Disease

Biomedical Chemistry Research and Methods ◽

10.18097/bmcrm00050 ◽

2018 ◽

Vol 1 (3) ◽

pp. e00050

Author(s):

P.N. Shevtsov ◽

E.F. Shevtsova ◽

S.O. Bachurin

Keyword(s):

Metal Ions ◽

Inferior Olive ◽

Postmortem Brain ◽

Control Group ◽

Destructive Effect ◽

Aluminum Ions ◽

Associated Proteins ◽

The Brain

The article provides an overview of our own results of comparative study of influence of ions of iron, zinc and aluminium on the structure of microtubules from tubulin and microtubules associated proteins of rat brain with data on the structure of microtubules from tubulin and microtubules associated proteins from the brain of patients with Alzheimer′s disease (AD). A significant decrease in the amount of soluble tubulin was found in the postmortem brain of AD patients in comparison with the control group in the hippocampus, frontal cortex and substantia nigra, but not in the inferior olive. In vitro polymerization of tubulin and microtubules associated proteins from the brain of AD patients and electron micrographs of microtubules were obtained. The assembly of microtubules from brains of AD patients is disrupted, resulting in defective structures. On the other hand, the study of the influence of Al3+, Fe3+, Zn2+ on the microtubules from rat brains tubulin and microtubules associated proteins assembly and structure has shown that all studied metals are able to reduce the amount of microtubules and induce the assembly of anomal structures. According to the degree of the destructive effect on the microtubules and, accordingly, the possible significance in the pathogenesis of Alzheimer disease, metal ions can be arranged in the following sequence Al3+ > Zn2+ > Fe3+. Moreover, phosphorylation of tubulin and microtubules associated proteins in the presence of aluminum ions to the greatest extent reflects the phosphorylation of these proteins at AD. Comparison of data on the structure of microtubules after their assembly from brains of AD patients tubulin and microtubules associated proteins from brains of AD patients, and from the brain of rats, but in the presence of metal ions, confirm the conclusion about the possible role of the metals in the AD etiopathogenesis.

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Drug Abuse-Related Neuroinflammation in Human Postmortem Brains: An Immunohistochemical Approach

Journal of Neuropathology & Experimental Neurology ◽

10.1093/jnen/nlz084 ◽

2019 ◽

Vol 78 (11) ◽

pp. 1059-1065 ◽

Cited By ~ 1

Author(s):

Matteo Moretti ◽

Giacomo Belli ◽

Luca Morini ◽

Maria Cristina Monti ◽

Antonio Marco Maria Osculati ◽

...

Keyword(s):

Adhesion Molecule ◽

Postmortem Brain ◽

Drug Abusers ◽

Immunohistochemical Markers ◽

Intracellular Adhesion Molecule ◽

Heroin Abusers ◽

Postmortem Brains ◽

And Control ◽

The Brain

Abstract The aim of the study was to investigate blood-brain barrier alterations, neuroinflammation, and glial responses in drug abusers. Five immunohistochemical markers (CD3, zonula occludens-1 [ZO-1], intracellular adhesion molecule 1 [ICAM-1], vascular cell adhesion molecule [VCAM-1], and glial fibrillary acidic protein [GFAP]) were assessed on postmortem brain samples collected from drug abusers who died from acute intoxication of cocaine, heroin, or a combination of both, compared with controls. CD3 and ICAM-1 immunopositivity were significantly stronger in drug abusers than in controls. VCAM-1 immunopositivity was similar across drug abuser and control groups. In heroin abusers, significantly lower ZO-1 immunopositivity was observed relative to controls. GFAP positivity did not show significant differences between groups, but its distribution within the brain did differ. Both cocaine and heroin abuse promoted neuroinflammation, increasing expression of ICAM-1 and recruiting CD3+ lymphocytes. Heroin affected the molecular integrity of tight junctions, as reflected by reduced ZO-1 expression. The outcomes of the present study are, overall, consistent with prior available evidence, which is almost exclusively from studies conducted in vitro or in animal models. These findings provide important information about the downstream consequences of neuroinflammation in drug abusers and may help to inform the development of potential therapeutic targets.

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Effect of pH and inhibitors on beta-amyloid fibril assembly

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100166221 ◽

1996 ◽

Vol 54 ◽

pp. 752-753

Author(s):

Beverly E. Maleeff ◽

Timothy K. Hart ◽

Stephen J. Wood ◽

Ronald Wetzel

Keyword(s):

Amyloid Fibril ◽

Peptide Fragment ◽

Hydrophobic Peptides ◽

Amyloid Fibril Formation ◽

Effects Of Ph ◽

Severity Of The Disease ◽

Kinetics Of ◽

The Brain

Alzheimer's disease is characterized post-mortem in part by abnormal extracellular neuritic plaques found in brain tissue. There appears to be a correlation between the severity of Alzheimer's dementia in vivo and the number of plaques found in particular areas of the brain. These plaques are known to be the deposition sites of fibrils of the protein β-amyloid. It is thought that if the assembly of these plaques could be inhibited, the severity of the disease would be decreased. The peptide fragment Aβ, a precursor of the p-amyloid protein, has a 40 amino acid sequence, and has been shown to be toxic to neuronal cells in culture after an aging process of several days. This toxicity corresponds to the kinetics of in vitro amyloid fibril formation. In this study, we report the biochemical and ultrastructural effects of pH and the inhibitory agent hexadecyl-N-methylpiperidinium (HMP) bromide, one of a class of ionic micellar detergents known to be capable of solubilizing hydrophobic peptides, on the in vitro assembly of the peptide fragment Aβ.

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