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Dobrowolski C, McGinley J, Fazzari M, Su J, Bingham KS, Anderson N, Ruttan L, Beaton DE, Wither JE, Tartaglia MC, Kakvan M, Bonilla D, Choi MY, Fritzler MJ, Diaz Martinez JP, Katz P, Green R, Putterman C, Touma Z. Association of mycophenolate and azathioprine use with cognitive function in systemic lupus. Rheumatology (Oxford) 2023; 62:1860-1869. [PMID: 36135792 PMCID: PMC10152298 DOI: 10.1093/rheumatology/keac540] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 08/26/2022] [Accepted: 09/14/2022] [Indexed: 11/14/2022] Open
Abstract
OBJECTIVES Cognitive dysfunction (CD) is a common manifestation of SLE that can have detrimental consequences for those affected. To date, no treatments have been approved for SLE-CD. This study aims to assess the association of azathioprine (AZA) and mycophenolate (MMF) use with SLE-CD, given that these medications have demonstrated neuroprotective qualities in prior studies. METHODS Consecutive adult SLE patients presenting to a single healthcare center were considered for participation. The ACR neuropsychological battery for SLE was administered to consenting patients at 0, 6 and 12 months. Scores were compared with age- and sex-matched controls. Primary outcome was CD, defined as a z-score ≤-1.5 in two or more cognitive domains. Mixed-effects logistic regression models were constructed to estimate the odds of CD with respect to AZA and MMF use. RESULTS A total of 300 participants representing 676 patient visits completed the study; 114 (38%) met criteria for CD at baseline. The cumulative AZA dose (g/kg) was associated with reduced odds of CD [odds ratio (OR) 0.76 (95% CI 0.58, 0.98), P = 0.04]. Years of AZA treatment was also associated with reduced odds of CD [OR 0.72 (95% CI 0.54, 0.97), P = 0.03]. MMF use was not associated with CD. CONCLUSION AZA use was associated with significantly lower odds of SLE-CD, while MMF use was not. Additional studies are warranted to further investigate the relationship of AZA and SLE-CD.
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Affiliation(s)
- Chrisanna Dobrowolski
- Division of Rheumatology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - John McGinley
- Department of Neurology, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Melissa Fazzari
- Department of Epidemiology and Population Health and Department of Obstetrics and Gynecology and Women's Health, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Jiandong Su
- University of Toronto Lupus Clinic, Centre for Prognosis Studies in Rheumatic Diseases, Toronto Western Hospital, Toronto, ON, Canada
| | - Kathleen S Bingham
- Centre for Mental Health, University Health Network; Department of Psychiatry, University of Toronto, Toronto, ON, Canada
| | - Nicole Anderson
- University of Toronto Lupus Clinic, Centre for Prognosis Studies in Rheumatic Diseases, Toronto Western Hospital, Toronto, ON, Canada
| | - Lesley Ruttan
- University Health Network-Toronto Rehabilitation Institute, Toronto, ON, Canada
| | - Dorcas E Beaton
- Institute for Work and Health, University of Toronto, Toronto, ON, Canada
| | - Joan E Wither
- University of Toronto Lupus Clinic, Centre for Prognosis Studies in Rheumatic Diseases, Toronto Western Hospital, Toronto, ON, Canada
| | | | - Mahta Kakvan
- University of Toronto Lupus Clinic, Centre for Prognosis Studies in Rheumatic Diseases, Toronto Western Hospital, Toronto, ON, Canada
| | - Dennisse Bonilla
- University of Toronto Lupus Clinic, Centre for Prognosis Studies in Rheumatic Diseases, Toronto Western Hospital, Toronto, ON, Canada
| | - May Y Choi
- Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Marvin J Fritzler
- Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Juan Pablo Diaz Martinez
- University of Toronto Lupus Clinic, Centre for Prognosis Studies in Rheumatic Diseases, Toronto Western Hospital, Toronto, ON, Canada
| | - Patricia Katz
- University of California, San Francisco, Novato, CA, USA
| | - Robin Green
- University Health Network-Toronto Rehabilitation Institute, Toronto, ON, Canada
| | - Chaim Putterman
- Department of Microbiology and Immunology, Albert Einstein School of Medicine, Bronx, NY, USA
- Division of Rheumatology, Albert Einstein College of Medicine, Bronx, NY, USA
- Azrieli School of Medicine, Safed, Israel
- Galillee Medical Center, Nahariya, Israel
| | - Zahi Touma
- University of Toronto Lupus Clinic, Centre for Prognosis Studies in Rheumatic Diseases, Toronto Western Hospital, Toronto, ON, Canada
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Kleine J, Hohmann U, Hohmann T, Ghadban C, Schmidt M, Laabs S, Alessandri B, Dehghani F. Microglia-Dependent and Independent Brain Cytoprotective Effects of Mycophenolate Mofetil During Neuronal Damage. Front Aging Neurosci 2022; 14:863598. [PMID: 35572146 PMCID: PMC9100558 DOI: 10.3389/fnagi.2022.863598] [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: 01/27/2022] [Accepted: 04/11/2022] [Indexed: 11/13/2022] Open
Abstract
Acute lesions of the central nervous system often lead to permanent limiting deficits. In addition to the initial primary damage, accompanying neuroinflammation is responsible for progression of damage. Mycophenolate mofetil (MMF) as a selective inhibitor of inosine 5-monophosphate dehydrogenase (IMPDH) was shown to modulate the inflammatory response and promote neuronal survival when applied in specific time windows after neuronal injury. The application of brain cytoprotective therapeutics early after neuronal damage is a fundamental requirement for a successful immunomodulation approach. This study was designed to evaluate whether MMF can still mediate brain cytoprotection when applied in predefined short time intervals following CNS injury. Furthermore, the role of microglia and changes in IMPDH2 protein expression were assessed. Organotypic hippocampal slice cultures (OHSC) were used as an in vitro model and excitotoxically lesioned with N-methyl-aspartate (NMDA). Clodronate (Clo) was used to deplete microglia and analyze MMF mediated microglia independent effects. The temporal expression of IMPDH2 was studied in primary glial cell cultures treated with lipopolysaccharide (LPS). In excitotoxically lesioned OHSC a significant brain cytoprotective effect was observed between 8 and 36 h but not within 8 and 24 h after the NMDA damage. MMF mediated effects were mainly microglia dependent at 24, 36, 48 h after injury. However, further targets like astrocytes seem to be involved in protective effects 72 h post-injury. IMPDH2 expression was detected in primary microglia and astrocyte cell cultures. Our data indicate that MMF treatment in OHSC should still be started no later than 8–12 h after injury and should continue at least until 36 h post-injury. Microglia seem to be an essential mediator of the observed brain cytoprotective effects. However, a microglia-independent effect was also found, indicating involvement of astrocytes.
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Affiliation(s)
- Joshua Kleine
- Department of Anatomy and Cell Biology, Medical Faculty, Martin-Luther-University Halle-Wittenberg, Halle (Saale), Germany
| | - Urszula Hohmann
- Department of Anatomy and Cell Biology, Medical Faculty, Martin-Luther-University Halle-Wittenberg, Halle (Saale), Germany
| | - Tim Hohmann
- Department of Anatomy and Cell Biology, Medical Faculty, Martin-Luther-University Halle-Wittenberg, Halle (Saale), Germany
| | - Chalid Ghadban
- Department of Anatomy and Cell Biology, Medical Faculty, Martin-Luther-University Halle-Wittenberg, Halle (Saale), Germany
| | - Miriam Schmidt
- Department of Anatomy and Cell Biology, Medical Faculty, Martin-Luther-University Halle-Wittenberg, Halle (Saale), Germany
| | - Sebastian Laabs
- Department of Anatomy and Cell Biology, Medical Faculty, Martin-Luther-University Halle-Wittenberg, Halle (Saale), Germany
| | - Beat Alessandri
- Institute for Neurosurgical Pathophysiology, University Medical Center, Johannes Gutenberg University, Mainz, Germany
| | - Faramarz Dehghani
- Department of Anatomy and Cell Biology, Medical Faculty, Martin-Luther-University Halle-Wittenberg, Halle (Saale), Germany
- *Correspondence: Faramarz Dehghani,
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Yang P, Lockard R, Titus H, Hiblar J, Weller K, Wafai D, Weleber RG, Duvoisin RM, Morgans CW, Pennesi ME. Suppression of cGMP-Dependent Photoreceptor Cytotoxicity With Mycophenolate Is Neuroprotective in Murine Models of Retinitis Pigmentosa. Invest Ophthalmol Vis Sci 2021; 61:25. [PMID: 32785677 PMCID: PMC7441375 DOI: 10.1167/iovs.61.10.25] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Purpose To determine the effect of mycophenolate mofetil (MMF) on retinal degeneration on two mouse models of retinitis pigmentosa. Methods Intraperitoneal injections of MMF were administered daily in rd10 and c57 mice starting at postoperative day 12 (P12) and rd1 mice starting at P8. The effect of MMF was assessed with optical coherence tomography, immunohistochemistry, electroretinography, and OptoMotry. Whole retinal cyclic guanosine monophosphate (cGMP) and mycophenolic acid levels were quantified with mass spectrometry. Photoreceptor cGMP cytotoxicity was evaluated with cell counts of cGMP immunostaining. Results MMF treatment significantly delays the onset of retinal degeneration and cGMP-dependent photoreceptor cytotoxicity in rd10 and rd1 mice, albeit a more modest effect in the latter. In rd10 mice, treatment with MMF showed robust preservation of the photoreceptors up to P22 with associated suppression of cGMP immunostaining and microglial activation; The neuroprotective effect diminished after P22, but outer retinal thickness was still significantly thicker by P35 and OptoMotry response was significantly better up to P60. Whereas cGMP immunostaining of the photoreceptors were present in rd10 and rd1 mice, hyperphysiological whole retinal cGMP levels were observed only in rd1 mice. Conclusions Early treatment with MMF confers potent neuroprotection in two animal models of RP by suppressing the cGMP-dependent common pathway for photoreceptor cell death. The neuroprotective effect of MMF on cGMP-dependent cytotoxicity occurs independently of the presence of hyperphysiological whole retinal cGMP levels. Thus our data suggest that MMF may be an important new class of neuroprotective agent that could be useful in the treatment of patients with RP.
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Affiliation(s)
- Paul Yang
- Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, United States
| | - Rachel Lockard
- School of Medicine, Oregon Health & Science University, Portland, Oregon, United States
| | - Hope Titus
- Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, United States
| | - Jordan Hiblar
- Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, United States
| | - Kyle Weller
- Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, United States
| | - Dahlia Wafai
- Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, United States
| | - Richard G Weleber
- Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, United States
| | - Robert M Duvoisin
- Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, Oregon, United States
| | - Catherine W Morgans
- Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, Oregon, United States
| | - Mark E Pennesi
- Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, United States
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Hu Z, Gajavelli S, Spurlock MS, Mahavadi A, Quesada LS, Gajavelli GR, Andreoni CB, Di L, Janecki J, Lee SW, Rivera KN, Shear DA, Bullock RM. Human neural stem cell transplant location-dependent neuroprotection and motor deficit amelioration in rats with penetrating traumatic brain injury. J Trauma Acute Care Surg 2020; 88:477-485. [PMID: 31626023 PMCID: PMC7098436 DOI: 10.1097/ta.0000000000002510] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 08/30/2019] [Accepted: 09/17/2019] [Indexed: 11/26/2022]
Abstract
BACKGROUND Penetrating traumatic brain injury induces chronic inflammation that drives persistent tissue loss long after injury. Absence of endogenous reparative neurogenesis and effective neuroprotective therapies render injury-induced disability an unmet need. Cell replacement via neural stem cell transplantation could potentially rebuild the tissue and alleviate penetrating traumatic brain injury disability. The optimal transplant location remains to be determined. METHODS To test if subacute human neural stem cell (hNSC) transplant location influences engraftment, lesion expansion, and motor deficits, rats (n = 10/group) were randomized to the following four groups (uninjured and three injured): group 1 (Gr1), uninjured with cell transplants (sham+hNSCs), 1-week postunilateral penetrating traumatic brain injury, after establishing motor deficit; group 2 (Gr2), treated with vehicle (media, no cells); group 3 (Gr3), hNSCs transplanted into lesion core (intra); and group 4 (Gr4), hNSCs transplanted into tissue surrounding the lesion (peri). All animals were immunosuppressed for 12 weeks and euthanized following motor assessment. RESULTS In Gr2, penetrating traumatic brain injury effect manifests as porencephalic cyst, 22.53 ± 2.87 (% of intact hemisphere), with p value of <0.0001 compared with uninjured Gr1. Group 3 lesion volume at 17.44 ± 2.11 did not differ significantly from Gr2 (p = 0.36), while Gr4 value, 9.17 ± 1.53, differed significantly (p = 0.0001). Engraftment and neuronal differentiation were significantly lower in the uninjured Gr1 (p < 0.05), compared with injured groups. However, there were no differences between Gr3 and Gr4. Significant increase in cortical tissue sparing (p = 0.03), including motor cortex (p = 0.005) was observed in Gr4 but not Gr3. Presence of transplant within lesion or in penumbra attenuated motor deficit development (p < 0.05) compared with Gr2. CONCLUSION In aggregate, injury milieu supports transplanted cell proliferation and differentiation independent of location. Unexpectedly, cortical sparing is transplant location dependent. Thus, apart from cell replacement and transplant mediated deficit amelioration, transplant location-dependent neuroprotection may be key to delaying onset or preventing development of injury-induced disability. LEVEL OF EVIDENCE Preclinical study evaluation of therapeutic intervention, level VI.
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Affiliation(s)
- Zhen Hu
- From the Department of Neurosurgery (Z.H.), Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, Guangdong, China; Miami Project to Cure Paralysis (Z.H., S.G., M.S.S., A.M., L.S.Q., G.R.G., C.B.A., L.D., J.J., S.W.L., K.N.R., R.M.D.), University of Miami, Miami, Florida; and Branch of Brain Trauma Neuroprotection and Neurorestoration (D.A.S.), Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research, Silver Spring, Maryland
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Mazumder AG, Patial V, Singh D. Mycophenolate mofetil contributes to downregulation of the hippocampal interleukin type 2 and 1β mediated PI3K/AKT/mTOR pathway hyperactivation and attenuates neurobehavioral comorbidities in a rat model of temporal lobe epilepsy. Brain Behav Immun 2019; 75:84-93. [PMID: 30243822 DOI: 10.1016/j.bbi.2018.09.020] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/30/2017] [Revised: 08/13/2018] [Accepted: 09/19/2018] [Indexed: 12/24/2022] Open
Abstract
The role of neuroinflammatory mediators has been well established in the pathogenesis of temporal lobe epilepsy (TLE) and associated neurobehavioral comorbidities. Mycophenolate mofetil (MMF) is commonly used as an immunosuppressant in organ transplantations. Its neuroprotective effect is well explored in different preclinical and clinical studies. The present study was designed to investigate the effect of MMF in rat model of lithium pilocarpine (LiPc)-induced spontaneous recurrent seizures and its associated neurobehavioral comorbidities. MMF treatment showed a dose-dependent decrease in seizure severity and reduced aggression in epileptic rats. There was marked improvement in spatial and recognition memory functions, along with substantial decrease in depression-like behavior in MMF treated epileptic rats. There was considerable decrease in mossy fiber sprouting in the dentate gyrus and the cornu ammonis 3 regions of the hippocampus, along with reduction in neuronal death in the treated groups. Furthermore, the hippocampal mRNA level of IL-1β, IL-2, PI3K, AKT, HIF-1α, RAPTOR, mTOR, Rps6kb1 and Rps6 was found to be decreased in MMF treated animals. mTOR, S6, pS6 and GFAP protein expression was decreased, whereas NeuN was increased in the rat hippocampus of the treated animals. The results concluded that MMF suppress recurrent seizures, and improves its associated behavioral impairments and cognitive deficit in rat model of TLE. The observed effects of MMF be correlated with the inhibition of IL-2 and IL-1β linked PI3K/AKT/mTOR signaling pathway hyperactivation.
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Affiliation(s)
- Arindam Ghosh Mazumder
- Pharmacology and Toxicology Laboratory, CSIR-Institute of Himalayan Bioresource Technology, Palampur 176061, Himachal Pradesh, India; Academy of Scientific and Innovative Research (AcSIR), CSIR-Institute of Himalayan Bioresource Technology, Palampur 176061, Himachal Pradesh, India
| | - Vikram Patial
- Pharmacology and Toxicology Laboratory, CSIR-Institute of Himalayan Bioresource Technology, Palampur 176061, Himachal Pradesh, India; Academy of Scientific and Innovative Research (AcSIR), CSIR-Institute of Himalayan Bioresource Technology, Palampur 176061, Himachal Pradesh, India
| | - Damanpreet Singh
- Pharmacology and Toxicology Laboratory, CSIR-Institute of Himalayan Bioresource Technology, Palampur 176061, Himachal Pradesh, India; Academy of Scientific and Innovative Research (AcSIR), CSIR-Institute of Himalayan Bioresource Technology, Palampur 176061, Himachal Pradesh, India.
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Sandhu HS, Lambert J, Xu Y, Kaplan HJ. Systemic immunosuppression and risk of age-related macular degeneration. PLoS One 2018; 13:e0203492. [PMID: 30235234 PMCID: PMC6147423 DOI: 10.1371/journal.pone.0203492] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Accepted: 08/21/2018] [Indexed: 11/18/2022] Open
Abstract
A local immune response has been implicated in the pathogenesis of age-related macular degeneration (AMD), but it is unclear if systemic immunosuppressive/immunomodulatory therapy (IMT) protects against the onset and/or progression of AMD. We performed a retrospective cohort study using a Cox proportional hazards model of two cohorts. Cohort 1 included patients with stage V chronic kidney disease (CKD) status post kidney transplantation, on at least one IMT agent, and older than 50. Cohort 2 included patients with stage IV or V CKD who had not undergone kidney transplantation, were not on IMT, and were older than 50. The main outcomes were hazard ratios of a new diagnosis of dry AMD, wet AMD, or conversion from dry to wet. There were 10,813 patients in cohort 1, and 217,081 patients in cohort 2. After controlling for sex and age, there was no significant difference in the hazard of developing a new diagnosis of dry AMD (HR = 0.95, 95% CI 0.87–1.05, p = 0.32), developing a new diagnosis of wet AMD without any prior diagnosis of dry AMD (HR = 0.85, 95% CI 0.66–1.08, p = 0.18), or converting from dry to wet AMD (HR 1.24, 95% CI 0.94–1.62, p = 0.12). For patients over 70 on mycophenolate mofetil, there was a reduced hazard of converting from dry to wet AMD (HR = 0.92, 95% CI = 0.85–0.99, p = 0.02). In contrast, everolimus had an increased hazard of dry AMD (HR = 2.14, 95% CI 1.24–3.69, p < 0.01). Most systemic IMT does not affect the risk of onset or progression of AMD in patients with CKD. However, mycophenolate mofetil may confer some degree of protection against the conversion of dry AMD to wet AMD, suggesting that modulation of the immune response may prevent progression of the disease.
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Affiliation(s)
- Harpal S. Sandhu
- Department of Ophthalmology and Visual Sciences, University of Louisville, Louisville, KY, United States of America
- * E-mail:
| | - Joshua Lambert
- Applied Statistics Lab, University of Kentucky, Louisville, KY, United States of America
| | - Yan Xu
- Applied Statistics Lab, University of Kentucky, Louisville, KY, United States of America
| | - Henry J. Kaplan
- Department of Ophthalmology and Visual Sciences, University of Louisville, Louisville, KY, United States of America
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Pieroh P, Wagner DC, Ghadban C, Birkenmeier G, Dehghani F. Ethyl pyruvate does not require microglia for mediating neuroprotection after excitotoxic injury. CNS Neurosci Ther 2017; 23:798-807. [PMID: 28836378 DOI: 10.1111/cns.12725] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Revised: 07/24/2017] [Accepted: 07/25/2017] [Indexed: 01/11/2023] Open
Abstract
AIMS Ethyl pyruvate (EP) mediates protective effects after neuronal injury. Besides a direct conservation of damaged neurons, the modulation of indigenous glial cells has been suggested as one important mechanism for EP-related neuroprotection. However, the specific contribution of glial cells is still unknown. METHODS Organotypic hippocampal slice cultures (OHSC) were excitotoxically lesioned by 50 μmol/L N-methyl-D-aspartate (NMDA, for 4 hours) or left untreated. In an additional OHSC subset, microglia was depleted using the bisphosphonate clodronate (100 μg/mL) before lesion. After removal of NMDA, EP containing culture medium (0.84 μmol/L, 8.4 μmol/L, 42 μmol/L, 84 μmol/L, 168 μmol/L) was added and incubated for 72 hours. OHSC were stained with propidium iodide to visualize degenerating neurons and isolectin IB4 -FITC to identify microglia. Effects of EP at concentrations of 0.84, 8.4, and 84 μmol/L (0-48 hours) were analyzed in the astrocytic scratch wound assay. RESULTS EP significantly reduced neurodegeneration following induced excitotoxicity except for 168 μmol/L. For 84 μmol/L, a reduction in the microglia cells was observed. Microglia depletion did not affect neuronal survival after EP treatment. EP decelerated astrocytic wound closure at 48 hours after injury. CONCLUSION EP-mediated neuroprotection seems to be mediated by astrocytes and/or neurons.
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Affiliation(s)
- Philipp Pieroh
- Department of Anatomy and Cell Biology, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany.,Department of Orthopedics, Trauma and Plastic Surgery, University of Leipzig, Leipzig, Germany
| | | | - Chalid Ghadban
- Department of Anatomy and Cell Biology, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
| | - Gerd Birkenmeier
- Institute of Biochemistry, University of Leipzig, Leipzig, Germany
| | - Faramarz Dehghani
- Department of Anatomy and Cell Biology, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
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The temporal and spatial dynamics of glyoxalase I following excitoxicity and brain ischaemia. Biochem Soc Trans 2015; 42:534-7. [PMID: 24646274 DOI: 10.1042/bst20140022] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
MG (methylglyoxal) is an inevitable metabolite derived from glycolysis leading to protein modification, mitochondrial dysfunction and cell death. The ubiquitous glyoxalase system detoxifies MG under GSH consumption by mean of Glo1 (glyoxalase I) as the rate-limiting enzyme. Neurons are highly vulnerable to MG, whereas astrocytes seem less susceptible due to their highly expressed glyoxalases. In neurodegenerative diseases, MG and Glo1 were found to be pivotal players in chronic CNS (central nervous system) diseases. Comparable results obtained upon MG treatment and NMDA (N-methyl-D-aspartate) receptor activation provided evidence of a possible link. Additional evidence was presented by alterations in Glo1 expression upon stimulation of excitotoxicity as an event in the aftermath of brain ischaemia. Glo1 expression was remarkably changed following ischaemia, and beneficial effects were found after exogenous application of Tat (transactivator of transcription)-Glo1. In summary, there are strong indications that Glo1 seems to be a suitable target to modulate the consequences of acute neuronal injury.
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Song Y, Li S, Song B, Zhang Y, Gao W, Li N, Fan K, Ma J. The pathological changes in the spinal cord after dural tear with and without autologous fascia repair. EUROPEAN SPINE JOURNAL : OFFICIAL PUBLICATION OF THE EUROPEAN SPINE SOCIETY, THE EUROPEAN SPINAL DEFORMITY SOCIETY, AND THE EUROPEAN SECTION OF THE CERVICAL SPINE RESEARCH SOCIETY 2014; 23:1531-40. [PMID: 24801575 DOI: 10.1007/s00586-014-3326-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Revised: 04/17/2014] [Accepted: 04/18/2014] [Indexed: 10/25/2022]
Abstract
PURPOSE Dural tear is one of the common complications of spinal surgery leading to cerebrospinal fluid leakage followed by serial secondary symptoms. However, little is known about pathological changes of the spinal cord after dural tear. In the present study, we aimed to study the pathological changes in the spinal cord after dural tear with and without autologous fascia repair. METHODS Sixty Sprague-Dawley rats were used for dural tear and autologous fascia graft repair models. Three days and 1 week after surgery, the pathological changes in the spinal cord were analyzed by immunohistochemistry, Western blot, enzyme-linked immunosorbent assay and spinal somatosensory evoked potentials test. RESULTS Neuroinflammation was found in the parenchyma of the spinal cord characterized by gliosis, increased expression of inflammatory factors and infiltration of exogenesis immunocells in the rats without repair, which impaired the sensory conduction function of the spinal cord at the early stage of injury. Repairing with autologous fascia could attenuate neuroinflammation and help to maintain normal sensory conduction function of the spinal cord. CONCLUSION Dural tear could cause a series of inflammatory reactions in the spinal cord and further impair its sensory conduction function at the early stage of injury. Repairing with autologous fascia was a necessary and effective way to prevent the neuroinflammation and to maintain the normal function of the spinal cord.
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Affiliation(s)
- Yi Song
- Graduate School of Dalian Medical University, Dalian, 116044, Liaoning, China,
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Ebrahimi F, Koch M, Pieroh P, Ghadban C, Hobusch C, Bechmann I, Dehghani F. Time dependent neuroprotection of mycophenolate mofetil: effects on temporal dynamics in glial proliferation, apoptosis, and scar formation. J Neuroinflammation 2012; 9:89. [PMID: 22569136 PMCID: PMC3430572 DOI: 10.1186/1742-2094-9-89] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2012] [Accepted: 05/08/2012] [Indexed: 12/14/2022] Open
Abstract
Background Immunosuppressants such as mycophenolate mofetil (MMF) have the capacity to inhibit microglial and astrocytic activation and to reduce the extent of cell death after neuronal injury. This study was designed to determine the effective neuroprotective time frame in which MMF elicits its beneficial effects, by analyzing glial cell proliferation, migration, and apoptosis. Methods Using organotypic hippocampal slice cultures (OHSCs), temporal dynamics of proliferation and apoptosis after N-methyl-D-aspartate (NMDA)-mediated excitotoxicity were analyzed by quantitative morphometry of Ki-67 or cleaved caspase-3 immunoreactive glial cells. Treatment on NMDA-lesioned OHSCs with mycophenolate mofetil (MMF)100 μg/mL was started at different time points after injury or performed within specific time frames, and the numbers of propidium iodide (PI)+ degenerating neurons and isolectin (I)B4+ microglial cells were determined. Pre-treatment with guanosine 100 μmol/l was performed to counteract MMF-induced effects. The effects of MMF on reactive astrocytic scar formation were investigated in the scratch-wound model of astrocyte monolayers. Results Excitotoxic lesion induction led to significant increases in glial proliferation rates between 12 and 36 hours after injury and to increased levels of apoptotic cells between 24 and 72 hours after injury. MMF treatment significantly reduced glial proliferation rates without affecting apoptosis. Continuous MMF treatment potently reduced the extent of neuronal cell demise when started within the first 12 hours after injury. A crucial time-frame of significant neuroprotection was identified between 12 and 36 hours after injury. Pre-treatment with the neuroprotective nucleoside guanosine reversed MMF-induced antiproliferative effects on glial cells. In the scratch-wound model, gap closure was reached within 48 hours in controls, and was potently inhibited by MMF. Conclusions Our data indicate that immunosuppression by MMF significantly attenuates the extent of neuronal cell death when administered within a crucial time frame after injury. Moreover, long-lasting immunosuppression, as required after solid-organ transplantation, does not seem to be necessary. Targeting inosine 5-monophosphate dehydrogenase, the rate-limiting enzyme of purine synthesis, is an effective strategy to modulate the temporal dynamics of proliferation and migration of microglia and astrocytes, and thus to reduce the extent of secondary neuronal damage and scar formation.
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Affiliation(s)
- Fahim Ebrahimi
- Institute of Anatomy, Leipzig University, Leipzig, Germany
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