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Villar-Delfino PH, Gomes NAO, Christo PP, Nogueira-Machado JA, Volpe CMO. Edaravone Inhibits the Production of Reactive Oxygen Species in Phagocytosis- and PKC-Stimulated Granulocytes from Multiple Sclerosis Patients Edaravone Modulate Oxidative Stress in Multiple Sclerosis. J Cent Nerv Syst Dis 2022; 14:11795735221092524. [PMID: 35599854 PMCID: PMC9121512 DOI: 10.1177/11795735221092524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Revised: 02/14/2022] [Accepted: 03/21/2022] [Indexed: 11/17/2022] Open
Abstract
Background Oxidative stress is associated with the pathogenesis of MS. Edaravone (EDV)
has been proposed as a therapeutic resource for central nervous system
diseases, and it was effective in reducing oxidative stress. However, the
antioxidant mechanisms of EDV are poorly studied. Objective This study aimed to evaluate the effects of EDV on resting, phagocytosis, and
PKC-activated granulocytes derived from MS patients and a healthy control
group. Methods The effects of EDV on ROS production in phagocytosis (ROS production in the
presence of opsonized particles) and PKC-stimulated granulocytes were
evaluated in a luminol-dependent chemiluminescence method. Calphostin C was
used in some experiments to compare with those of EDV. Results EDV inhibited ROS production in phagocytosis of opsonized particles and
PKC-stimulated granulocytes from MS patients and healthy control group. In
the presence of calphostin C, the inhibition of ROS production was similar
to that observed with EDV. Conclusion These findings suggest the involvement of EDV on the ROS-PKC-NOX signaling
pathways modulating oxidative stress in MS. EDV represents a promising
treatment option to control oxidative innate immune response for MS.
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Affiliation(s)
- Pedro Henrique Villar-Delfino
- Faculdade Santa Casa BH, Programa de Pós-Graduação Stricto Sensu em Medicina-Biomedicina, Santa Casa BH, Belo Horizonte, Minas Gerais, Brazil
| | - Nathália Augusta Oliveira Gomes
- Faculdade Santa Casa BH, Programa de Pós-Graduação Stricto Sensu em Medicina-Biomedicina, Santa Casa BH, Belo Horizonte, Minas Gerais, Brazil
| | - Paulo Pereira Christo
- Faculdade Santa Casa BH, Programa de Pós-Graduação Stricto Sensu em Medicina-Biomedicina, Santa Casa BH, Belo Horizonte, Minas Gerais, Brazil
| | - José Augusto Nogueira-Machado
- Faculdade Santa Casa BH, Programa de Pós-Graduação Stricto Sensu em Medicina-Biomedicina, Santa Casa BH, Belo Horizonte, Minas Gerais, Brazil
| | - Caroline Maria Oliveira Volpe
- Faculdade Santa Casa BH, Programa de Pós-Graduação Stricto Sensu em Medicina-Biomedicina, Santa Casa BH, Belo Horizonte, Minas Gerais, Brazil
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2
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Amirinejad R, Shirvani-Farsani Z, Naghavi Gargari B, Sahraian MA, Mohammad Soltani B, Behmanesh M. Vitamin D changes expression of DNA repair genes in the patients with multiple sclerosis. Gene 2021; 781:145488. [PMID: 33588040 DOI: 10.1016/j.gene.2021.145488] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 01/18/2021] [Accepted: 02/02/2021] [Indexed: 12/31/2022]
Abstract
Oxidative stress (OS) plays an essential role in demyelination and tissue injury related to pathogenesis of multiple sclerosis (MS). On the other hand, vitamin D (VD) as an antioxidant reduces oxidative stress and has been used as adjuvant therapy in autoimmune diseases. Although VD supplementation is suggested as a protective and immunomodulation factor for MS patients, the molecular mechanisms remain unclear. Given that VD may modulate the immune system of MS patients through the DNA repair pathway, we aimed to evaluate the effects of VD supplementation in DNA repair genes expression including OGG1, MYH, MTH1, and ITPA. Transcript levels were measured using the RT-qPCR method in peripheral blood mononuclear cells (PBMCs) of relapsing-remitting multiple sclerosis (RRMS) patients before and after two months of VD supplementation. Furthermore, in silico analysis and correlation gene expression analysis was performed to find the biological binding sites and the effect of NRF2 on the regulation of DNA repair genes. Our data revealed that in MS patients, 2-month VD treatment significantly altered the expression of MYH, OGG1, MTH1, and NRF2 genes. A significant correlation was observed between DNA repair genes and NRF2 expression, which was confirmed by the presence of antioxidant response element (ARE) binding sites in the promoter of OGG1, MYH, and MTH1 genes. This study demonstrated that the impact of VD on MS patients may be mediated through the improvement of DNA repair system efficiency. This finding brought some new evidence for the involvement of DNA repair genes in the physiopathology of MS patients.
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Affiliation(s)
- Roya Amirinejad
- Department of Genetics, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran
| | - Zeinab Shirvani-Farsani
- Department of Cell and Molecular Biology, Faculty of Biological Sciences and Technology, Shahid Beheshti University G.C., Tehran, Iran
| | - Bahar Naghavi Gargari
- Department of Basic Sciences, Faculty Nursing and Midwifery Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohhamad Ali Sahraian
- MS Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran
| | - Bahram Mohammad Soltani
- Department of Genetics, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran
| | - Mehrdad Behmanesh
- Department of Genetics, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran.
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3
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Wang S, Liu Y, Li G, Feng Q, Hou M, Peng J. Reduced intracellular antioxidant capacity in platelets contributes to primary immune thrombocytopenia via ROS-NLRP3-caspase-1 pathway. Thromb Res 2020; 199:1-9. [PMID: 33383234 DOI: 10.1016/j.thromres.2020.12.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Revised: 11/23/2020] [Accepted: 12/09/2020] [Indexed: 02/07/2023]
Abstract
Primary immune thrombocytopenia (ITP) is a common acquired autoimmune hemorrhagic disease characterized by a low platelet count and increased risk of bleeding. However, some patients do not respond well to current therapeutic approaches. Further studies on pathogenesis and pathophysiology of ITP are needed to discover new therapeutic targets. We explored the role of enhanced intracellular oxidative stress and NLRP3 inflammasome activation of platelets in ITP. The expression of NLRP3 inflammasome was assessed in platelets from active ITP patients and healthy donors. Both the mRNA and protein expression level of platelet NLRP3 inflammasome was upregulated in ITP patients compared with healthy donors. Besides, the elevated caspase-1 activity and increased co-localization of NLRP3 and its adaptor molecule ASC indicated activation of NLRP3 inflammasome in ITP platelets. Significantly decreased intracellular antioxidant capacity was observed in ITP platelets. H2O2 supplementation elevated the expression of NLRP3 inflammasome and increased IL-1β secretion in ITP platelets. Preincubating ITP platelets with NAC down-regulated the expression of NLRP3 inflammasome. Pretreating ITP platelets with NLRP3 inhibitor MCC950 or caspase-1 inhibitor Z-YVAD-FMK significantly reduced the proportion of pyroptotic cells in H2O2-treated ITP platelets and suppressed IL-1β secretion in supernatants. Hence, platelet NLRP3 inflammasome activation resulted from reduced intracellular antioxidant capacity plays a critical role in ITP and might have potential diagnostic or therapeutic implications.
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Affiliation(s)
- Shuang Wang
- Department of Hematology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China; Department of Medical Oncology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Yang Liu
- Department of Hematology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Guosheng Li
- Department of Hematology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Qi Feng
- Department of Hematology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Ming Hou
- Department of Hematology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China; Shandong Provincial Key Laboratory of Immunohematology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China; Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education and Chinese Ministry of Health, Jinan, China.
| | - Jun Peng
- Department of Hematology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China; Shandong Provincial Key Laboratory of Immunohematology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China.
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4
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Ng X, Sadeghian M, Heales S, Hargreaves IP. Assessment of Mitochondrial Dysfunction in Experimental Autoimmune Encephalomyelitis (EAE) Models of Multiple Sclerosis. Int J Mol Sci 2019; 20:ijms20204975. [PMID: 31600882 PMCID: PMC6829485 DOI: 10.3390/ijms20204975] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 10/03/2019] [Accepted: 10/07/2019] [Indexed: 01/03/2023] Open
Abstract
Multiple sclerosis (MS) is an inflammatory demyelinating disease of the central nervous system (CNS) that involves the autoreactive T-cell attack on axonal myelin sheath. Lesions or plaques formed as a result of repeated damage and repair mechanisms lead to impaired relay of electrical impulses along the nerve, manifesting as clinical symptoms of MS. Evidence from studies in experimental autoimmune encephalomyelitis (EAE) models of MS strongly suggests that mitochondrial dysfunction presents at the onset of disease and throughout the disease course. The aim of this study was to determine if mitochondrial dysfunction occurs before clinical symptoms arise, and whether this is confined to the CNS. EAE was induced in C57B/L6 mice, and citrate synthase and mitochondrial respiratory chain (MRC) complex I–IV activities were assayed at presymptomatic (3 or 10 days post first immunisation (3 or 10 DPI)) and asymptomatic (17 days post first immunisation (17 DPI) time-points in central nervous system (CNS; spinal cord) and peripheral (liver and jaw muscle) tissues. Samples from animals immunised with myelin oligodendrocyte glycoprotein (MOG) as EAE models were compared with control animals immunised with adjuvant (ADJ) only. Significant changes in MOG compared to control ADJ animals in MRC complex I activity occurred only at presymptomatic stages, with an increase in the spinal cord at 10 DPI (87.9%), an increase at 3 DPI (25.6%) and decrease at 10 DPI (22.3%) in the jaw muscle, and an increase in the liver at 10 DPI (71.5%). MRC complex II/III activity changes occurred at presymptomatic and the asymptomatic stages of the disease, with a decrease occurring in the spinal cord at 3 DPI (87.6%) and an increase at 17 DPI (36.7%), increase in the jaw muscle at 10 DPI (25.4%), and an increase at 3 DPI (75.2%) and decrease at 17 DPI (95.7%) in the liver. Citrate synthase activity was also significantly decreased at 10 DPI (27.3%) in the liver. No significant changes were observed in complex IV across all three tissues assayed. Our findings reveal evidence that mitochondrial dysfunction is present at the asymptomatic stages in the EAE model of MS, and that the changes in MRC enzyme activities are tissue-specific and are not confined to the CNS.
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Affiliation(s)
- Xiulin Ng
- UCL Institute of Neurology, Queen Square, University College London, London WC1N 3BG, UK.
- University Medical Center, 79106 Freiburg im Breisgau, Germany.
| | - Mona Sadeghian
- Department of Neuroinflammation, Queen Square Multiple Sclerosis Centre, UCL Institute of Neurology, London WC1N 3BG, UK.
- Global Clinical Development, Actelion, High Wycombe HP12 4DP, UK.
| | - Simon Heales
- Department of Molecular Neuroscience, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK.
- Neurometabolic Unit, National Hospital, London WC1N 3BG, UK.
| | - Iain P Hargreaves
- Department of Molecular Neuroscience, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK.
- Neurometabolic Unit, National Hospital, London WC1N 3BG, UK.
- School of Pharmacy and Biomolecular Sciences, Byrom Street, Liverpool John Moores University, Liverpool L3 3AF, UK.
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5
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Ganelin-Cohen E, Golderman S, Yeskaraev R, Rozenberg A, Livneh A, Kaplan B. Search for new biomarkers of pediatric multiple sclerosis: application of immunoglobulin free light chain analysis. Clin Chem Lab Med 2019; 56:1081-1089. [PMID: 29408796 DOI: 10.1515/cclm-2017-0911] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Accepted: 12/18/2017] [Indexed: 11/15/2022]
Abstract
BACKGROUND Identifying new biomarkers is needed to overcome the diagnostic difficulties of pediatric multiple sclerosis (MS). Recently, we developed a new technique including CSF analysis of free light chain (FLC) monomers and dimers, which can improve diagnosis of adult MS. The present study has been designed to evaluate the utility of our technique for MS diagnosis in children. METHODS Patients with MS (n=21) and non-MS demyelinating or inflammatory neurological disorders (n=35) participated in the study. MS diagnosis was based on clinical and magnetic resonance imaging (MRI) findings. Western blot analysis was applied to examine FLC in the patients' CSF and serum. FLC indices for FLC monomer and dimer levels and κ/λ ratios were estimated. The samples were also analyzed by oligoclonality test. RESULTS The study revealed abnormally elevated levels of κ-FLC monomers and dimers in the CSF of 10 MS patients ("κ-type MS"). Increased amounts of λ dimers were found in six MS cases ("λ-type MS"), while high levels of both κ and λ FLC ("mixed type MS") were documented in three MS cases. MRI and clinical assessment showed a more aggressive disease form for the "mixed" and "λ-type" cases. Our method demonstrated higher sensitivity (90.5%) and specificity (91.4%) for discrimination between MS and non-MS patients, as compared to oligoclonality test (81% and 65.7%, respectively). CONCLUSIONS The proposed method may significantly contribute to diagnosis and prognosis of pediatric MS.
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Affiliation(s)
- Esther Ganelin-Cohen
- Institute of Pediatric Neurology, Schneider Children's Medical Center, Petach Tikva 49202, Israel.,Sackler School of Medicine, Tel-Aviv University, Tel-Aviv, Israel
| | - Sizilia Golderman
- Heller Institute of Medical Research, Sheba Medical Center, Tel-Hashomer, Ramat Gan, Israel
| | - Regina Yeskaraev
- Department of Clinical Biochemistry, Sheba Medical Center, Tel-Hashomer, Ramat Gan, Israel
| | - Ayal Rozenberg
- Department of Neuroimmunology, Rambam Health Care Campus, Haifa, Israel
| | - Avi Livneh
- Sackler School of Medicine, Tel-Aviv University, Tel-Aviv, Israel.,Heller Institute of Medical Research, Sheba Medical Center, Tel-Hashomer, Ramat Gan, Israel
| | - Batia Kaplan
- Heller Institute of Medical Research, Sheba Medical Center, Tel-Hashomer, Ramat Gan, Israel
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6
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Karahalil B, Orhan G, Ak F. The impact of detoxifying and repair gene polymorphisms and the levels of serum ROS in the susceptibility to multiple sclerosis. Clin Neurol Neurosurg 2015; 139:288-94. [DOI: 10.1016/j.clineuro.2015.10.028] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Revised: 09/04/2015] [Accepted: 10/21/2015] [Indexed: 10/22/2022]
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7
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Allizond V, Scutera S, Rossi S, Musso T, Crocillà C, Cavalla P, Trebini C, Marra ES, Cuffini AM, Banche G. Polymorphonuclear Cell Functional Impairment in Relapsing Remitting Multiple Sclerosis Patients: Preliminary Data. PLoS One 2015; 10:e0131557. [PMID: 26121651 PMCID: PMC4488035 DOI: 10.1371/journal.pone.0131557] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Accepted: 06/03/2015] [Indexed: 12/17/2022] Open
Abstract
Multiple Sclerosis patients run an increased risk of microbial infections, which leads to high rates of hospitalization and infection-related mortality. Although immunotherapy may increase infection risk in some cases, data as to the relationship among microbial factors, immunotherapy and alterations in the innate immunity of these patients are still scanty. On these grounds, this interdisciplinary study aims at investigating the role the functional activity of polymorphonuclear cells (PMNs) play in relapsing remitting multiple sclerosis at different stages. The in vitro ability of PMNs from patients, either untreated or treated with immunosuppressant or immunomodulatory drugs to kill Klebsiella pneumonia or Candida albicans, were investigated and compared to PMNs from healthy subjects. The release of various cytokines was also assessed, as was the production of reactive oxygen species and their ability to regulate apoptosis after microbial stimulation. Our results indicate that although patients have a normal number of PMNs, they have a statistically significant (p<0.05) reduction in intracellular killing activity. Although variations are strongly related to the therapeutic management of patients, they are independent from their disease stage. As no statistically significant differences were observed between patients and controls in cytokine release values, reactive oxygen species production or apoptosis, we came to the conclusion that other factors may be involved. Supportive validation of these results from further studies might well help in identifying a subset of patients at high risk of infection who could benefit from a closer follow-up and/or antibiotic prophylaxis.
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Affiliation(s)
- Valeria Allizond
- Bacteriology and Mycology Laboratory, Department of Public Health and Pediatrics, University of Torino, Turin, Italy
| | - Sara Scutera
- Immunology Laboratory, Department of Public Health and Pediatrics, University of Torino, Turin, Italy
| | - Silvia Rossi
- Immunology Laboratory, Department of Public Health and Pediatrics, University of Torino, Turin, Italy
| | - Tiziana Musso
- Immunology Laboratory, Department of Public Health and Pediatrics, University of Torino, Turin, Italy
| | | | - Paola Cavalla
- Department of Neuroscience, University of Torino, Turin, Italy
| | - Claudia Trebini
- Department of Neuroscience, University of Torino, Turin, Italy
| | - Elisa Simona Marra
- Bacteriology and Mycology Laboratory, Department of Public Health and Pediatrics, University of Torino, Turin, Italy
| | - Anna Maria Cuffini
- Bacteriology and Mycology Laboratory, Department of Public Health and Pediatrics, University of Torino, Turin, Italy
| | - Giuliana Banche
- Bacteriology and Mycology Laboratory, Department of Public Health and Pediatrics, University of Torino, Turin, Italy
- * E-mail:
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8
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Peluso I, Manafikhi H, Reggi R, Palmery M. Interference of flavonoids with fluorescent intracellular probes: methodological implications in the evaluation of the oxidative burst by flow cytometry. Cytometry A 2014; 85:663-77. [PMID: 24889089 DOI: 10.1002/cyto.a.22490] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2013] [Revised: 03/10/2014] [Accepted: 05/12/2014] [Indexed: 12/12/2022]
Abstract
The evaluation of oxidative burst is particularly relevant in many pathological and subclinical conditions. Flow cytometry provides quick and accurate measures of the reactive oxygen species production by leukocytes in most situations. However, spurious results, related to probes' efflux may be observed in several instances. Many factors affect the evaluation of the oxidative burst with fluorescent probes that require intracellular deacetylation and could be substrate of the multidrug resistance proteins (MDR). After discussing the implications of the efflux of fluorophores in the normalization strategies in flow cytometry assays, we have pointed out the possible interference of flavonoids with fluorescet probes' staining and signal. We have also reviewed the results from human intervention studies regarding the evaluation of oxidative burst with these probes. In vitro, at concentrations close to post-ingestion circulating levels, some flavonoids and their metabolites could interfere with probes' staining and fluorescence signal through different mechanisms, such as the inhibition of esterases, the modulation of the MDR-mediate efflux of probe and the inhibition of the oxidation of probe. These effects may explain the contrasting results obtained by human intervention studies. Finally, also inflammatory state or the use of drugs substrate of MDR proteins could affect the evaluation of the oxidative burst with intracellular probes.
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Affiliation(s)
- Ilaria Peluso
- Department of Physiology and Pharmacology, "V. Erspamer," "Sapienza" University of Rome, Italy
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9
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Abstract
Histochemical and MRI studies have demonstrated that MS (multiple sclerosis) patients have abnormal deposition of iron in both gray and white matter structures. Data is emerging indicating that this iron could partake in pathogenesis by various mechanisms, e.g., promoting the production of reactive oxygen species and enhancing the production of proinflammatory cytokines. Iron chelation therapy could be a viable strategy to block iron-related pathological events or it can confer cellular protection by stabilizing hypoxia inducible factor 1α, a transcription factor that normally responds to hypoxic conditions. Iron chelation has been shown to protect against disease progression and/or limit iron accumulation in some neurological disorders or their experimental models. Data from studies that administered a chelator to animals with experimental autoimmune encephalomyelitis, a model of MS, support the rationale for examining this treatment approach in MS. Preliminary clinical studies have been performed in MS patients using deferoxamine. Although some side effects were observed, the large majority of patients were able to tolerate the arduous administration regimen, i.e., 6-8 h of subcutaneous infusion, and all side effects resolved upon discontinuation of treatment. Importantly, these preliminary studies did not identify a disqualifying event for this experimental approach. More recently developed chelators, deferasirox and deferiprone, are more desirable for possible use in MS given their oral administration, and importantly, deferiprone can cross the blood-brain barrier. However, experiences from other conditions indicate that the potential for adverse events during chelation therapy necessitates close patient monitoring and a carefully considered administration regimen.
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10
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Initial immunopathogenesis of multiple sclerosis: innate immune response. Clin Dev Immunol 2013; 2013:413465. [PMID: 24174969 PMCID: PMC3794540 DOI: 10.1155/2013/413465] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2013] [Revised: 07/01/2013] [Accepted: 08/09/2013] [Indexed: 12/13/2022]
Abstract
Multiple sclerosis (MS) is an inflammatory, demyelinating, and neurodegenerative disease of the central nervous system. The hallmark to MS is the demyelinated plaque, which consists of a well-demarcated hypocellular area characterized by the loss of myelin, the formation of astrocytic scars, and the mononuclear cell infiltrates concentrated in perivascular spaces composed of T cells, B lymphocytes, plasma cells, and macrophages. Activation of resident cells initiates an inflammatory cascade, leading to tissue destruction, demyelination, and neurological deficit. The immunological phenomena that lead to the activation of autoreactive T cells to myelin sheath components are the result of multiple and complex interactions between environment and genetic background conferring individual susceptibility. Within the CNS, an increase of TLR expression during MS is observed, even in the absence of any apparent microbial involvement. In the present review, we focus on the role of the innate immune system, the first line of defense of the organism, as promoter and mediator of cross reactions that generate molecular mimicry triggering the inflammatory response through an adaptive cytotoxic response in MS.
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11
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Polymorphisms of paraoxonase 1 and 2 genes and the risk of multiple sclerosis in the Polish population. Neurol Neurochir Pol 2013; 47:49-52. [PMID: 23487294 DOI: 10.5114/ninp.2013.32935] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BACKGROUND AND PURPOSE The aim of this study was to test the hypothesis that polymorphisms of the paraoxonase genes PON1 and PON2 may be associated with increased risk of developing multiple sclerosis (MS) in the Polish population. MATERIAL AND METHODS We studied the significance of the PON gene polymorphisms C311S, A162G, Q192R and L55M in 221 patients (including 145 women) with MS and in 661 healthy controls. In the MS population, mean Expanded Disability Status Scale score was 2.92, mean age was 36.8 years, and mean disease duration was 7.7 years. PON genotyping was determined using polymerase chain reaction and restriction enzyme digestion. RESULTS According to our results, the PON1 and PON2 genotypes distribution did not differ between the MS patients and the controls. CONCLUSIONS The polymorphisms of the PON genes studied are not related to increased risk of MS in the Polish population.
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12
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Kaplan B, Golderman S, Yahalom G, Yeskaraev R, Ziv T, Aizenbud BM, Sela BA, Livneh A. Free light chain monomer–dimer patterns in the diagnosis of multiple sclerosis. J Immunol Methods 2013; 390:74-80. [DOI: 10.1016/j.jim.2013.01.010] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2013] [Revised: 01/24/2013] [Accepted: 01/25/2013] [Indexed: 11/16/2022]
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13
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Naegele M, Tillack K, Reinhardt S, Schippling S, Martin R, Sospedra M. Neutrophils in multiple sclerosis are characterized by a primed phenotype. J Neuroimmunol 2011; 242:60-71. [PMID: 22169406 DOI: 10.1016/j.jneuroim.2011.11.009] [Citation(s) in RCA: 143] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2011] [Revised: 11/16/2011] [Accepted: 11/17/2011] [Indexed: 12/22/2022]
Abstract
Neutrophils are armed with proteases with indiscriminate histotoxic potential, and to minimize tissue injury, their activation involves priming with inflammatory mediators before cells are fully activated in a second step. Here, we show that neutrophils in multiple sclerosis patients are more numerous and exhibit a primed state based on reduced apoptosis, higher expression of TLR-2, fMLP receptor, IL-8 receptor and CD43, enhanced degranulation and oxidative burst as well as higher levels of neutrophil extracellular traps in serum. The chronic inflammatory environment in multiple sclerosis probably underlies this inappropriate neutrophil priming, which may result in enhanced neutrophil activation during infection.
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Affiliation(s)
- Matthias Naegele
- Institute for Neuroimmunology and Clinical MS Research (inims), Center for Molecular Neurobiology Hamburg (ZMNH), University Medical Center-Eppendorf, Falkenried 94, 20251 Hamburg (UKE), Germany
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14
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Williams R, Buchheit CL, Berman NEJ, LeVine SM. Pathogenic implications of iron accumulation in multiple sclerosis. J Neurochem 2011; 120:7-25. [PMID: 22004421 DOI: 10.1111/j.1471-4159.2011.07536.x] [Citation(s) in RCA: 112] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Iron, an essential element used for a multitude of biochemical reactions, abnormally accumulates in the CNS of patients with multiple sclerosis (MS). The mechanisms of abnormal iron deposition in MS are not fully understood, nor do we know whether these deposits have adverse consequences, that is, contribute to pathogenesis. With some exceptions, excess levels of iron are represented concomitantly in multiple deep gray matter structures often with bilateral representation, whereas in white matter, pathological iron deposits are usually located at sites of inflammation that are associated with veins. These distinct spatial patterns suggest disparate mechanisms of iron accumulation between these regions. Iron has been postulated to promote disease activity in MS by various means: (i) iron can amplify the activated state of microglia resulting in the increased production of proinflammatory mediators; (ii) excess intracellular iron deposits could promote mitochondria dysfunction; and (iii) improperly managed iron could catalyze the production of damaging reactive oxygen species (ROS). The pathological consequences of abnormal iron deposits may be dependent on the affected brain region and/or accumulation process. Here, we review putative mechanisms of enhanced iron uptake in MS and address the likely roles of iron in the pathogenesis of this disease.
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Affiliation(s)
- Rachel Williams
- Department of Molecular & Integrative Physiology, University of Kansas Medical Center, Kansas City, Kansas 66160, USA
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15
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Ferretti G, Bacchetti T. Peroxidation of lipoproteins in multiple sclerosis. J Neurol Sci 2011; 311:92-7. [PMID: 21967834 DOI: 10.1016/j.jns.2011.09.004] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2011] [Revised: 09/01/2011] [Accepted: 09/05/2011] [Indexed: 01/29/2023]
Abstract
Human plasma low density lipoproteins (LDL) and high density lipoproteins (HDL) are involved in the transport of lipids, modulate membrane lipid composition and regulate signal transduction. HDL-like lipoproteins have been shown also in human cerebrospinal fluid and it has been hypothesized that they could have a role in lipid transport in central nervous system. After synthesis, lipoproteins are susceptible to lipid peroxidation triggered by reactive oxygen species (ROS and RNS) produced by peripheral and brain cells. Aim of the paper has been to review the scientific literature on the role of lipid peroxidation of LDL and HDL in the molecular mechanisms of multiple sclerosis (MS). Several studies have demonstrated a significant increase in lipid peroxidation products in brain, plasma and cerebrospinal fluid of MS patients. The increase of antibodies against ox-LDL in plasma and the presence of ox-LDL in demyelinating plaques in MS brain suggests that the disease is associated with oxidative damage of lipoproteins. The impairment of antioxidant systems or an increase in the production of ROS and RNS could contribute to lipoprotein peroxidation in MS. Oxidized lipoproteins show several alterations of their functions, they are neurotoxic and have pro-inflammatory properties. Therefore lipoprotein lipid peroxidation products could be involved in demyelination and axonal injury in MS.
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Affiliation(s)
- Gianna Ferretti
- Dipartimento di Scienze Cliniche Sperimentali e Odontostomatologiche, Università Politecnica delle Marche, 60131 Ancona, Italy.
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Castegna A, Palmieri L, Spera I, Porcelli V, Palmieri F, Fabis-Pedrini MJ, Kean RB, Barkhouse DA, Curtis MT, Hooper DC. Oxidative stress and reduced glutamine synthetase activity in the absence of inflammation in the cortex of mice with experimental allergic encephalomyelitis. Neuroscience 2011; 185:97-105. [PMID: 21536110 DOI: 10.1016/j.neuroscience.2011.04.041] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2010] [Revised: 03/31/2011] [Accepted: 04/16/2011] [Indexed: 01/19/2023]
Abstract
Pathological changes occur in areas of CNS tissue remote from inflammatory lesions in multiple sclerosis (MS) and its animal model experimental allergic encephalomyelitis (EAE). To determine if oxidative stress is a significant contributor to this non-inflammatory pathology, cortex tissues from mice with clinical signs of EAE were examined for evidence of inflammation and oxidative stress. Histology and gene expression analysis showed little evidence of immune/inflammatory cell invasion but reductions in natural antioxidant levels and increased protein oxidation that paralleled disease severity. Two-dimensional oxyblots and mass-spectrometry-based protein fingerprinting identified glutamine synthetase (GS) as a particular target of oxidation. Oxidation of GS was associated with reductions in enzyme activity and increased glutamate/glutamine levels. The possibility that this may cause neurodegeneration through glutamate excitotoxicity is supported by evidence of increasing cortical Ca(2+) levels in cortex extracts from animals with greater disease severity. These findings indicate that oxidative stress occurs in brain areas that are not actively undergoing inflammation in EAE and that this can lead to a neurodegenerative process due to the susceptibility of GS to oxidative inactivation.
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MESH Headings
- Analysis of Variance
- Animals
- Calcium/metabolism
- Cerebral Cortex/enzymology
- Chromatography, High Pressure Liquid/methods
- Disease Models, Animal
- Electrophoresis, Gel, Two-Dimensional
- Encephalitis/pathology
- Encephalomyelitis, Autoimmune, Experimental/etiology
- Encephalomyelitis, Autoimmune, Experimental/pathology
- Encephalomyelitis, Autoimmune, Experimental/physiopathology
- Female
- Glutamate-Ammonia Ligase/analysis
- Glutamate-Ammonia Ligase/metabolism
- Glutamic Acid/metabolism
- Glutamine/metabolism
- Glutathione/metabolism
- Glutathione Disulfide/metabolism
- Guinea Pigs
- Mice
- Myelin Basic Protein/adverse effects
- Myelin Basic Protein/immunology
- NAD/metabolism
- NADP/metabolism
- Nitric Oxide Synthase Type II/metabolism
- Oxidative Stress/physiology
- Tandem Mass Spectrometry/methods
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Affiliation(s)
- A Castegna
- Department of Pharmaco-Biology, Laboratory of Biochemistry and Molecular Biology, University of Bari, Via Orabona 4, 70125 Bari, Italy
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Choi IY, Lee SP, Denney DR, Lynch SG. Lower levels of glutathione in the brains of secondary progressive multiple sclerosis patients measured by 1H magnetic resonance chemical shift imaging at 3 T. Mult Scler 2010; 17:289-96. [PMID: 20921235 DOI: 10.1177/1352458510384010] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
BACKGROUND Disability levels for patients with secondary progressive multiple sclerosis (SPMS) often worsen despite a stable MRI T(2) lesion burden. The presence of oxidative stress in the absence of measurable inflammation could help explain this phenomenon. In this study, the assessment of an in vivo marker of oxidative stress, cerebral glutathione (GSH), using magnetic resonance chemical shift imaging (CSI) is described, and GSH levels were compared in patients with SPMS and healthy controls. OBJECTIVE To assess whether GSH, a key antioxidant in the brain, is lower in the SPMS patients compared to matched controls. METHODS Seventeen patients with SPMS (Expanded Disability Status Scale=4.0-7.0; length of MS diagnosis=19.4 ± 7 years) and 17 age- and gender-matched healthy controls were studied. GSH levels were measured in the fronto-parietal regions of the brain using a specially designed magnetic resonance spectroscopy technique, CSI of GSH, at 3T. RESULTS The levels of GSH were lower for SPMS patients than for controls, the largest reduction (18.5%) being in the frontal region (p=0.001). CONCLUSION The lower GSH levels in these patients indicate the presence of oxidative stress in SPMS. This process could be at least partially responsible for ongoing functional decline in SPMS.
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Affiliation(s)
- I-Y Choi
- Hoglund Brain Imaging Center, Department of Neurology, University of Kansas Medical Center, Kansas City, KS 66160, USA.
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18
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Reactive oxygen intermediate-induced pathomechanisms contribute to immunosenescence, chronic inflammation and autoimmunity. Mech Ageing Dev 2009; 130:564-87. [PMID: 19632262 DOI: 10.1016/j.mad.2009.07.003] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2008] [Revised: 06/07/2009] [Accepted: 07/15/2009] [Indexed: 02/07/2023]
Abstract
Deregulation of reactive oxygen intermediates (ROI) resulting in either too high or too low concentrations are commonly recognized to be at least in part responsible for many changes associated with aging. This article reviews ROI-dependent mechanisms critically contributing to the decline of immune function during physiologic - or premature - aging. While ROI serve important effector functions in cellular metabolism, signalling and host defence, their fine-tuned generation declines over time, and ROI-mediated damage to several cellular components and/or signalling deviations become increasingly prevalent. Although distinct ROI-associated pathomechanisms contribute to immunosenescence of the innate and adaptive immune system, mutual amplification of dysfunctions may often result in hyporesponsiveness and immunodeficiency, or in chronic inflammation with hyperresponsiveness/deregulation, or both. In this context, we point out how imbalanced ROI contribute ambiguously to driving immunosenescence, chronic inflammation and autoimmunity. Although ROI may offer a distinct potential for therapeutic targeting along with the charming opportunity to rescue from deleterious processes of aging and chronic inflammatory diseases, such modifications, owing to the complexity of metabolic interactions, may carry a marked risk of unforeseen side effects.
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Greve B, Hoffmann P, Vonthein R, Kun J, Lell B, Mycko MP, Selmaj KW, Berger K, Weissert R, Kremsner PG. NCF1 gene and pseudogene pattern: association with parasitic infection and autoimmunity. Malar J 2008; 7:251. [PMID: 19077231 PMCID: PMC2635379 DOI: 10.1186/1475-2875-7-251] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2008] [Accepted: 12/11/2008] [Indexed: 11/10/2022] Open
Abstract
Background Neutrophil cytosolic factor 1, p47phox (NCF1) is a component of the leukocyte NADPH oxidase complex mediating formation of reactive oxygen intermediates (ROI) which play an important role in host defense and autoimmunity. An individual genomic pattern of ncf1 and its two types of pseudogenes (reflected by the ΔGT/GTGT ratio) may influence the individual capacity to produce ROI. Methods NCF1ΔGT/GTGT ratios were correlated with clinical parameters and ROI production during Plasmodium falciparum malaria and with susceptibility to the autoimmune disease multiple sclerosis (MS). Results Among Gabonese children with severe malaria, ROI production from peripheral blood tended to be higher in individuals with a ΔGT/GTGT ratio ≤ 1:1. ΔGT/GTGT ratios were not associated with susceptibility to MS, but to age-of-onset among MS patients. Conclusion The genomic pattern of NCF1 and its pseudogenes might influence ROI production but only marginally influence susceptibility to and outcome of malaria and MS.
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Affiliation(s)
- Bernhard Greve
- Hertie Institute for Clinical Brain Research, Department of General Neurology, University of Tübingen, Tübingen, Germany.
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20
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Gelderman KA, Hultqvist M, Olsson LM, Bauer K, Pizzolla A, Olofsson P, Holmdahl R. Rheumatoid arthritis: the role of reactive oxygen species in disease development and therapeutic strategies. Antioxid Redox Signal 2007; 9:1541-67. [PMID: 17678439 DOI: 10.1089/ars.2007.1569] [Citation(s) in RCA: 98] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Autoimmune diseases such as rheumatoid arthritis (RA) are chronic diseases that cannot be prevented or cured If the pathologic basis of such disease would be known, it might be easier to develop new drugs interfering with critical pathway. Genetic analysis of animal models for autoimmune diseases can result in discovery of proteins and pathways that play key function in pathogenesis, which may provide rationales for new therapeutic strategies. Currently, only the MHC class II is clearly associated with human RA and animal models for RA. However, recent data from rats and mice with a polymorphism in Ncf1, a member of the NADPH oxidase complex, indicate a role for oxidative burst in protection from arthritis. Oxidative burst-activating substances can treat and prevent arthritis in rats, as efficiently as clinically applied drugs, suggesting a novel pathway to a therapeutic target in human RA. Here, the authors discuss the role of oxygen radicals in regulating the immune system and autoimmune disease. It is proposed that reactive oxygen species set the threshold for T cell activation and thereby regulate chronic autoimmune inflammatory diseases like RA. In the light of this new hypothesis, new possibilities for preventive and therapeutic treatment of chronic inflammatory diseases are discussed.
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Affiliation(s)
- Kyra A Gelderman
- Unit for Medical Inflammation Research, Department of Experimental Medical Science, Lund University, Lund, Sweden
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Mattsson N, Haghighi S, Andersen O, Yao Y, Rosengren L, Blennow K, Praticò D, Zetterberg H. Elevated cerebrospinal fluid F2-isoprostane levels indicating oxidative stress in healthy siblings of multiple sclerosis patients. Neurosci Lett 2007; 414:233-6. [PMID: 17227694 DOI: 10.1016/j.neulet.2006.12.044] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2006] [Revised: 12/15/2006] [Accepted: 12/18/2006] [Indexed: 12/31/2022]
Abstract
Lipid peroxidation has been implicated in the pathogenesis of multiple sclerosis (MS). Isoprostanes, isomers of prostaglandins, are produced by free radical-mediated peroxidation of fatty acids in vivo and can be quantified in biological fluids. This study examines the levels of cerebrospinal fluid (CSF) F2-isoprostanes (F2-iPs) in MS patients (n=46), their healthy siblings (n=46) and unrelated controls (n=50). The median CSF F2-iP concentration (range) was significantly higher in siblings of MS patients, as compared to healthy controls (40.0 [7.1-68.7] and 29.1 [6.4-60.3] pg/mL, respectively, p=0.031). MS patients demonstrated F2-iP levels intermediate between siblings and controls. F2-iP levels in MS patients and siblings correlated significantly (R=0.360, p=0.012). These results suggest that siblings of MS patients have an increased oxidative stress response to environmental and/or genetic factors that may be involved in MS pathogenesis.
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Affiliation(s)
- Niklas Mattsson
- Clinical Neurochemistry Laboratory, Department of Neuroscience and Physiology, Sahlgren's University Hospital, S-431 80 Mölndal, Sweden
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22
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Yadav V, Bourdette D. Complementary and alternative medicine: is there a role in multiple sclerosis? Curr Neurol Neurosci Rep 2007; 6:259-67. [PMID: 16635436 DOI: 10.1007/s11910-006-0014-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Despite effective conventional therapies for multiple sclerosis (MS), many people with MS explore complementary and alternative medicine (CAM) therapies for their symptoms. Common CAM therapies that people use include dietary modification, nutritional and herbal supplementation, and mind-body therapies. There is a revival of interest among MS researchers about the therapeutic potential of low-fat diet and essential fatty acid supplementation in MS. The efficacy of specific vitamin supplementation remains unclear. Recently, cannabis and yoga have been studied in more controlled studies and have provided evidence that they may have some benefit. The research on CAM therapies in MS is still exploratory, but considering peoples' interest and common use of these therapies, further research in this area is clearly warranted.
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Affiliation(s)
- Vijayshree Yadav
- Department of Neurology L226, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA.
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Lev N, Ickowicz D, Barhum Y, Blondheim N, Melamed E, Offen D. Experimental encephalomyelitis induces changes in DJ-1: implications for oxidative stress in multiple sclerosis. Antioxid Redox Signal 2006; 8:1987-95. [PMID: 17034344 DOI: 10.1089/ars.2006.8.1987] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
DJ-1 plays an important role in oxidative stress, and is involved in various neurodegenerative diseases. Accumulating evidence suggests a central role for oxidative stress in multiple sclerosis (MS). The aim of this study was to examine whether changes occur in DJ-1 expression in an animal model of MS, experimental autoimmune encephalomyelitis (EAE). We found upregulation of DJ-1 mRNA and protein expression levels in EAE and a correlation between disease severity and increased DJ-1 levels. Although DJ-1 isoforms were more alkaline in controls, in EAE, a shift was noted toward acidic isoforms. ROS induced by SIN-I exposure led to an increase in DJ-1 mRNA and protein levels in human glioma U-87 cells. Immunocytochemical staining demonstrated that DJ-1 is present both in the cytoplasm and the nuclei of these cells. This is the first report of modulation of DJ-1 expression in EAE. Upregulation of DJ-1 was noted in EAE, and similar results were observed in glioma cells exposed to ROS. In view of the accumulating evidence on the central role of oxidative stress in MS, and the importance of DJ-1 in oxidative stress management by the CNS, we believe that DJ-1 will be found to have a central role in MS.
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Affiliation(s)
- Nirit Lev
- Laboratory of Neuroscience and department of Neurology, FMRC, Rabin Medical Center, Tel Aviv University, Petah-Tikva, Israel.
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Angelova P, Müller W. Oxidative modulation of the transient potassium current IAby intracellular arachidonic acid in rat CA1 pyramidal neurons. Eur J Neurosci 2006; 23:2375-84. [PMID: 16706845 DOI: 10.1111/j.1460-9568.2006.04767.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Oxidative stress affects cellular membrane lipids and proteins. Using whole-cell patch-clamp recording we demonstrate differential oxidative inhibition of voltage-gated transient (IA) and delayed rectifier [IK(V)] K+ currents by arachidonic acid (AA) and H2O2 in CA1 neurons in hippocampal slice. We show that intracellular application of 1 pm AA or its non-metabolizable analog eicosatetraynoic acid (100 pm) reduced IA by approximately 42% but did not affect IK(V). AA shifted the voltage dependence of steady-state inactivation of IA by 12 mV to more negative potentials whereas the rate of inactivation was unchanged. Surprisingly, intracellular glutathione (GSH, 20 mm) enhanced the effect of AA on maximal IA (-62%) and with AA slowed inactivation of IA. The combination of GSH and extracellular ascorbate (0.4 mm) prevented reduction of IA by AA. Intracellular Trolox (a vitamin E analog, 10 microm) reduced IA by 61%and IK(V) by 39%. Like AA, intracellular Trolox caused a 10-mV left shift of IA steady-state inactivation but Trolox and AA did not cause a shift when coapplied. Extracellular Trolox (100 microm) had no effects on IA. H2O2 (80 microm) reduced both IA and IK(V) in a GSH- and ascorbate-sensitive manner and slowed the rate of inactivation of IA by a factor of 2. Coapplication of H2O2 with GSH and extracellular ascorbate caused approximately 22 mV negative shifts of both steady-state inactivation and activation. We conclude that AA is extremely potent in affecting IA by oxidative modifications. Antioxidants can augment these effects, probably by catalysis of the underlying reactions between oxidants and IA channel proteins.
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Affiliation(s)
- Plamena Angelova
- Neuroscience Research Institute, Charité, Humboldt University, Berlin, Germany
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