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Zhou C, Satpute V, Yip KL, Anderson LL, Hawkins N, Kearney J, Arnold JC. A high seizure burden increases several prostaglandin species in the hippocampus of a Scn1a +/- mouse model of Dravet syndrome. Prostaglandins Other Lipid Mediat 2024; 172:106836. [PMID: 38599513 DOI: 10.1016/j.prostaglandins.2024.106836] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Revised: 04/02/2024] [Accepted: 04/05/2024] [Indexed: 04/12/2024]
Abstract
Dravet syndrome is an intractable epilepsy with a high seizure burden that is resistant to current anti-seizure medications. There is evidence that neuroinflammation plays a role in epilepsy and seizures, however few studies have specifically examined neuroinflammation in Dravet syndrome under conditions of a higher seizure burden. Here we used an established genetic mouse model of Dravet syndrome (Scn1a+/- mice), to examine whether a higher seizure burden impacts the number and morphology of microglia in the hippocampus. Moreover, we examined whether a high seizure burden influences classical inflammatory mediators in this brain region. Scn1a+/- mice with a high seizure burden induced by thermal priming displayed a localised reduction in microglial cell density in the granule cell layer and subgranular zone of the dentate gyrus, regions important to postnatal neurogenesis. However, microglial cell number and morphology remained unchanged in other hippocampal subfields. The high seizure burden in Scn1a+/- mice did not affect hippocampal mRNA expression of classical inflammatory mediators such as interleukin 1β and tumour necrosis factor α, but increased cyclooxygenase 2 (COX-2) expression. We then quantified hippocampal levels of prostanoids that arise from COX-2 mediated metabolism of fatty acids and found that Scn1a+/- mice with a high seizure burden displayed increased hippocampal concentrations of numerous prostaglandins, notably PGF2α, PGE2, PGD2, and 6-K-PGF1A, compared to Scn1a+/- mice with a low seizure burden. In conclusion, a high seizure burden increased hippocampal concentrations of various prostaglandin mediators in a mouse model of Dravet syndrome. Future studies could interrogate the prostaglandin pathways to further better understand their role in the pathophysiology of Dravet syndrome.
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Affiliation(s)
- Cilla Zhou
- Lambert Initiative for Cannabinoid Therapeutics, The University of Sydney, Sydney, NSW 2050, Australia; Discipline of Pharmacology, School of Pharmacy, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW 2006, Australia; Brain and Mind Centre, The University of Sydney, Sydney, NSW 2050, Australia; Department of Pharmacology, Feinberg School of Medicine, Northwestern University, IL 60611, USA
| | - Vaishali Satpute
- Lambert Initiative for Cannabinoid Therapeutics, The University of Sydney, Sydney, NSW 2050, Australia; Discipline of Pharmacology, School of Pharmacy, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW 2006, Australia; Brain and Mind Centre, The University of Sydney, Sydney, NSW 2050, Australia
| | - Ka Lai Yip
- Lambert Initiative for Cannabinoid Therapeutics, The University of Sydney, Sydney, NSW 2050, Australia; Discipline of Pharmacology, School of Pharmacy, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW 2006, Australia; Brain and Mind Centre, The University of Sydney, Sydney, NSW 2050, Australia
| | - Lyndsey L Anderson
- Lambert Initiative for Cannabinoid Therapeutics, The University of Sydney, Sydney, NSW 2050, Australia; Discipline of Pharmacology, School of Pharmacy, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW 2006, Australia; Brain and Mind Centre, The University of Sydney, Sydney, NSW 2050, Australia
| | - Nicole Hawkins
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, IL 60611, USA
| | - Jennifer Kearney
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, IL 60611, USA
| | - Jonathon C Arnold
- Lambert Initiative for Cannabinoid Therapeutics, The University of Sydney, Sydney, NSW 2050, Australia; Discipline of Pharmacology, School of Pharmacy, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW 2006, Australia; Brain and Mind Centre, The University of Sydney, Sydney, NSW 2050, Australia.
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Araki T, Hiragi T, Kuga N, Luo C, Andoh M, Sugao K, Nagata H, Sasaki T, Ikegaya Y, Koyama R. Microglia induce auditory dysfunction after status epilepticus in mice. Glia 2024; 72:274-288. [PMID: 37746760 DOI: 10.1002/glia.24472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Revised: 09/08/2023] [Accepted: 09/14/2023] [Indexed: 09/26/2023]
Abstract
Auditory dysfunction and increased neuronal activity in the auditory pathways have been reported in patients with temporal lobe epilepsy, but the cellular mechanisms involved are unknown. Here, we report that microglia play a role in the disinhibition of auditory pathways after status epilepticus in mice. We found that neuronal activity in the auditory pathways, including the primary auditory cortex and the medial geniculate body (MGB), was increased and auditory discrimination was impaired after status epilepticus. We further demonstrated that microglia reduced inhibitory synapses on MGB relay neurons over an 8-week period after status epilepticus, resulting in auditory pathway hyperactivity. In addition, we found that local removal of microglia from the MGB attenuated the increase in c-Fos+ relay neurons and improved auditory discrimination. These findings reveal that thalamic microglia are involved in auditory dysfunction in epilepsy.
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Affiliation(s)
- Tasuku Araki
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
| | - Toshimitsu Hiragi
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
| | - Nahoko Kuga
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan
| | - Cong Luo
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
| | - Megumi Andoh
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
| | | | | | - Takuya Sasaki
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan
| | - Yuji Ikegaya
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
- Institute for AI and Beyond, The University of Tokyo, Tokyo, Japan
- Center for Information and Neural Networks, National Institute of Information and Communications Technology, Osaka, Japan
| | - Ryuta Koyama
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
- Institute for AI and Beyond, The University of Tokyo, Tokyo, Japan
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3
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Lai AY, Almanza DLV, Ribeiro JA, Hill ME, Mandrozos M, Koletar MM, Stefanovic B, McLaurin J. Obesity Facilitates Sex-Specific Improvement In Cognition And Neuronal Function In A Rat Model Of Alzheimer's Disease. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.11.575200. [PMID: 38328066 PMCID: PMC10849478 DOI: 10.1101/2024.01.11.575200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2024]
Abstract
Obesity reduces or increases the risk of developing Alzheimer's disease (AD) depending on whether it is assessed in mid-life or late-life. There is currently no consensus on the relationship between obesity and AD or the mechanism or their interaction. Here, we aim to differentiate the cause-and-effect relationship between obesity and AD in a controlled rat model of AD. We induced obesity in 9-month-old TgF344-AD rats, that is pathology-load wise similar to early symptomatic phase of human AD. To more accurately model human obesity, we fed both TgF344-AD and non-transgenic littermates a varied high-carbohydrate-high-fat diet consisting of human food for 3 months. Obesity increased overall glucose metabolism and slowed cognitive decline in TgF344-AD rats, specifically executive function, without affecting non-transgenic rats. Pathological analyses of prefrontal cortex and hippocampus showed that obesity in TgF344-AD rats produced varied effects, with increased density of myelin and oligodendrocytes, lowered density and activation of microglia that we propose contributes to the cognitive improvement. However, obesity also decreased neuronal density, and promoted deposition of amyloid-beta plaques and tau inclusions. After 6 months on the high-carbohydrate-high-fat diet, detrimental effects on density of neurons, amyloid-beta plaques, and tau inclusions persisted while the beneficial effects on myelin, microglia, and cognitive functions remained albeit with a lower effect size. By examining the effect of sex, we found that both beneficial and detrimental effects of obesity were stronger in female TgF344-AD rats indicating that obesity during early symptomatic phase of AD is protective in females.
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Nguyen DA, Stone MF, Schultz CR, de Araujo Furtado M, Niquet J, Wasterlain CG, Lumley LA. Evaluation of Midazolam-Ketamine-Allopregnanolone Combination Therapy against Cholinergic-Induced Status Epilepticus in Rats. J Pharmacol Exp Ther 2024; 388:376-385. [PMID: 37770198 PMCID: PMC10801769 DOI: 10.1124/jpet.123.001784] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 09/01/2023] [Accepted: 09/06/2023] [Indexed: 10/03/2023] Open
Abstract
Status epilepticus (SE) is a life-threatening development of self-sustaining seizures that becomes resistant to benzodiazepines when treatment is delayed. Benzodiazepine pharmacoresistance is thought in part to result from internalization of synaptic GABAA receptors, which are the main target of the drug. The naturally occurring neurosteroid allopregnanolone is a therapy of interest against SE for its ability to modulate all isoforms of GABAA receptors. Ketamine, an N-methyl-D-aspartate (NMDA) receptor antagonist, has been partially effective in combination with benzodiazepines in mitigating SE-associated neurotoxicity. In this study, allopregnanolone as an adjunct to midazolam or midazolam-ketamine combination therapy was evaluated for efficacy against cholinergic-induced SE. Adult male rats implanted with electroencephalographic (EEG) telemetry devices were exposed to the organophosphorus chemical (OP) soman (GD) and treated with an admix of atropine sulfate and HI-6 at 1 minute after exposure followed by midazolam, midazolam-allopregnanolone, or midazolam-ketamine-allopregnanolone 40 minutes after seizure onset. Neurodegeneration, neuronal loss, and neuroinflammation were assessed 2 weeks after GD exposure. Seizure activity, EEG power integral, and epileptogenesis were also compared among groups. Overall, midazolam-ketamine-allopregnanolone combination therapy was effective in reducing cholinergic-induced toxic signs and neuropathology, particularly in the thalamus and hippocampus. Higher dosage of allopregnanolone administered in combination with midazolam and ketamine was also effective in reducing EEG power integral and epileptogenesis. The current study reports that there is a promising potential of neurosteroids in combination with benzodiazepine and ketamine treatments in a GD model of SE. SIGNIFICANCE STATEMENT: Allopregnanolone, a naturally occurring neurosteroid, reduced pathologies associated with soman (GD) exposure such as epileptogenesis, neurodegeneration, and neuroinflammation, and suppressed GD-induced toxic signs when used as an adjunct to midazolam and ketamine in a delayed treatment model of soman-induced status epilepticus (SE) in rats. However, protection was incomplete, suggesting that further studies are needed to identify optimal combinations of antiseizure medications and routes of administration for maximal efficacy against cholinergic-induced SE.
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Affiliation(s)
- Donna A Nguyen
- Neuroscience Department, US Army Medical Research Institute of Chemical Defense (USAMRICD), Aberdeen Proving Ground, Maryland (D.A.N., M.F.S., C.R.S., L.A.L.); BioSEaD, LLC, Rockville, Maryland (M.D.A.F.); Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, California (J.N., C.G.W.); and Epilepsy Research Laboratory (151), Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, California (J.N., C.G.W.)
| | - Michael F Stone
- Neuroscience Department, US Army Medical Research Institute of Chemical Defense (USAMRICD), Aberdeen Proving Ground, Maryland (D.A.N., M.F.S., C.R.S., L.A.L.); BioSEaD, LLC, Rockville, Maryland (M.D.A.F.); Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, California (J.N., C.G.W.); and Epilepsy Research Laboratory (151), Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, California (J.N., C.G.W.)
| | - Caroline R Schultz
- Neuroscience Department, US Army Medical Research Institute of Chemical Defense (USAMRICD), Aberdeen Proving Ground, Maryland (D.A.N., M.F.S., C.R.S., L.A.L.); BioSEaD, LLC, Rockville, Maryland (M.D.A.F.); Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, California (J.N., C.G.W.); and Epilepsy Research Laboratory (151), Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, California (J.N., C.G.W.)
| | - Marcio de Araujo Furtado
- Neuroscience Department, US Army Medical Research Institute of Chemical Defense (USAMRICD), Aberdeen Proving Ground, Maryland (D.A.N., M.F.S., C.R.S., L.A.L.); BioSEaD, LLC, Rockville, Maryland (M.D.A.F.); Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, California (J.N., C.G.W.); and Epilepsy Research Laboratory (151), Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, California (J.N., C.G.W.)
| | - Jerome Niquet
- Neuroscience Department, US Army Medical Research Institute of Chemical Defense (USAMRICD), Aberdeen Proving Ground, Maryland (D.A.N., M.F.S., C.R.S., L.A.L.); BioSEaD, LLC, Rockville, Maryland (M.D.A.F.); Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, California (J.N., C.G.W.); and Epilepsy Research Laboratory (151), Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, California (J.N., C.G.W.)
| | - Claude G Wasterlain
- Neuroscience Department, US Army Medical Research Institute of Chemical Defense (USAMRICD), Aberdeen Proving Ground, Maryland (D.A.N., M.F.S., C.R.S., L.A.L.); BioSEaD, LLC, Rockville, Maryland (M.D.A.F.); Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, California (J.N., C.G.W.); and Epilepsy Research Laboratory (151), Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, California (J.N., C.G.W.)
| | - Lucille A Lumley
- Neuroscience Department, US Army Medical Research Institute of Chemical Defense (USAMRICD), Aberdeen Proving Ground, Maryland (D.A.N., M.F.S., C.R.S., L.A.L.); BioSEaD, LLC, Rockville, Maryland (M.D.A.F.); Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, California (J.N., C.G.W.); and Epilepsy Research Laboratory (151), Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, California (J.N., C.G.W.)
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Kim SH, Ju IG, Kim JH, Eo H, Son SR, Jang DS, Oh MS. Linderae Radix Ameliorates Cognitive Dysfunction by Inhibiting Neuroinflammation and Synaptic Damage in Alzheimer's Disease Models. Mol Neurobiol 2023; 60:7196-7207. [PMID: 37542650 DOI: 10.1007/s12035-023-03544-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Accepted: 07/27/2023] [Indexed: 08/07/2023]
Abstract
Neuroinflammation and synaptic damage are important etiologies associated with the progression of Alzheimer's disease (AD). Linderae Radix (LR) has antioxidant and anti-inflammatory properties. This study investigated whether LR attenuates microglia activation-mediated neuroinflammation and synaptic degeneration and improves AD pathological phenotypes induced by amyloid beta oligomers (AβO) or lipopolysaccharide (LPS) toxicity. For in vitro studies, we treated LR to AβO-stimulated HT22 cells or LR LPS-stimulated BV2 cells. For in vivo studies, we administered LR to mice and AβO was injected by stereotaxic to induce cognitive impairment, neuroinflammation, and synaptic loss. We found that LR increased the cell viability reduced by AβO. Moreover, LR inhibited pro-inflammatory mediators such as nitric oxide (NO), inducible NO synthase (iNOS), and cyclooxygenase-2 (COX-2), and downregulated p38 mitogen-activated protein kinase (MAPK) signaling in BV2 cells. Behavioral assessments demonstrated that LR administration significantly improved cognitive decline induced by AβO-injection. Furthermore, we found that microglia activation increased, and the expression of synaptic proteins decreased in the hippocampus of the AβO-injected group, which was alleviated in the LR-treated group. These findings suggest that LR may be a potential candidate for protection against neuroinflammation and synaptic loss, and may prevent or delay AD progression.
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Affiliation(s)
- Seong Hye Kim
- Department of Biomedical and Pharmaceutical Sciences, Graduate School, Kyung Hee University, 26, Kyungheedae-Ro, Dongdaemun-Gu, Seoul, 02447, Republic of Korea
| | - In Gyoung Ju
- Department of Oriental Pharmaceutical Science and Kyung Hee East-West Pharmaceutical Research Institute, College of Pharmacy, Kyung Hee University, 26, Kyungheedae-Ro, Dongdaemun-Gu, Seoul, 02447, Republic of Korea
| | - Jin Hee Kim
- Department of Biomedical and Pharmaceutical Sciences, Graduate School, Kyung Hee University, 26, Kyungheedae-Ro, Dongdaemun-Gu, Seoul, 02447, Republic of Korea
| | - Hyeyoon Eo
- Department of Biomedical and Pharmaceutical Sciences, Graduate School, Kyung Hee University, 26, Kyungheedae-Ro, Dongdaemun-Gu, Seoul, 02447, Republic of Korea
| | - So-Ri Son
- Department of Biomedical and Pharmaceutical Sciences, Graduate School, Kyung Hee University, 26, Kyungheedae-Ro, Dongdaemun-Gu, Seoul, 02447, Republic of Korea
| | - Dae Sik Jang
- Department of Biomedical and Pharmaceutical Sciences, Graduate School, Kyung Hee University, 26, Kyungheedae-Ro, Dongdaemun-Gu, Seoul, 02447, Republic of Korea
| | - Myung Sook Oh
- Department of Biomedical and Pharmaceutical Sciences, Graduate School, Kyung Hee University, 26, Kyungheedae-Ro, Dongdaemun-Gu, Seoul, 02447, Republic of Korea.
- Department of Oriental Pharmaceutical Science and Kyung Hee East-West Pharmaceutical Research Institute, College of Pharmacy, Kyung Hee University, 26, Kyungheedae-Ro, Dongdaemun-Gu, Seoul, 02447, Republic of Korea.
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Rao NS, Putra M, Meyer C, Almanza A, Thippeswamy T. The effects of Src tyrosine kinase inhibitor, saracatinib, on the markers of epileptogenesis in a mixed-sex cohort of adult rats in the kainic acid model of epilepsy. Front Mol Neurosci 2023; 16:1294514. [PMID: 38025259 PMCID: PMC10665569 DOI: 10.3389/fnmol.2023.1294514] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Accepted: 10/25/2023] [Indexed: 12/01/2023] Open
Abstract
Neurodegeneration and neuroinflammation are key processes of epileptogenesis in temporal lobe epilepsy (TLE). A considerable number (∼30%) of patients with epilepsy are resistant to currently available antiseizure drugs and thus there is a need to develop adjunct therapies to modify disease progression. A vast majority of interventional strategies to treat TLE have utilized males which limits the translational nature of the studies. In this study, we investigated the effects of repeated low-dose kainic acid (KA) injection on the initial status epilepticus (SE) and the effects of Src kinase inhibitor, saracatinib (SAR/AZD0530; 20 mg/kg, oral, daily for 7 days), in a mixed-sex cohort of adult Sprague Dawley rats during early epileptogenesis. There were no sex differences in response to KA-induced SE, and neither did the stage of estrus influence SE severity. KA-induced SE caused significant astrogliosis and microgliosis across the hippocampus, piriform cortex, and amygdala. SAR treatment resulted in a significant reduction of microgliosis across brain regions. Microglial morphometrics such as branch length and the endpoints strongly correlated with CD68 expression in the vehicle-treated group but not in the SAR-treated group, indicating mitigation by SAR. KA-induced SE caused significant neuronal loss, including parvalbumin-positive inhibitory neurons, in both vehicle (VEH) and SAR-treated groups. SAR treatment significantly mitigated FJB-positive neuronal counts as compared to the VEH group. There was an increase in C3-positive reactive astrocytes in the VEH-treated group, and SAR treatment significantly reduced the increase in the piriform cortex. C3-positive astrogliosis significantly correlated with CD68 expression in the amygdala (AMY) of VEH-treated rats, and SAR treatment mitigated this relationship. There was a significant increase of pSrc(Y419)-positive microglia in both KA-treated groups with a statistically insignificant reduction by SAR. KA-induced SE caused the development of classical glial scars in the piriform cortex (PIR) in both KA-treated groups, while SAR treatment led to a 42.17% reduction in the size of glial scars. We did not observe sex differences in any of the parameters in this study. SAR, at the dose tested in the rat kainate model for a week in this study mitigated some of the markers of epileptogenesis in both sexes.
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Affiliation(s)
| | | | | | | | - Thimmasettappa Thippeswamy
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, IA, United States
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Que Z, Olivero-Acosta MI, Chen I, Zhang J, Wettschurack K, Wu J, Xiao T, Otterbacher CM, Wang M, Harlow H, Cui N, Chen X, Deming B, Halurkar M, Zhao Y, Rochet JC, Xu R, Brewster AL, Wu LJ, Yuan C, Skarnes WC, Yang Y. Human iPSC-derived microglia sense and dampen hyperexcitability of cortical neurons carrying the epilepsy-associated SCN2A-L1342P mutation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.26.563426. [PMID: 37961213 PMCID: PMC10634902 DOI: 10.1101/2023.10.26.563426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
Neuronal hyperexcitability is a hallmark of seizures. It has been recently shown in rodent models of seizures that microglia, the brain's resident immune cells, can respond to and modulate neuronal excitability. However, how human microglia interacts with human neurons to regulate hyperexcitability mediated by epilepsy-causing genetic mutation found in human patients remains unknown. The SCN2A genetic locus is responsible for encoding the voltage-gated sodium channel Nav1.2, recognized as one of the leading contributors to monogenic epilepsies. Previously, we demonstrated that the recurring Nav1.2-L1342P mutation identified in patients with epilepsy leads to hyperexcitability in a hiPSC-derived cortical neuron model from a male donor. While microglia play an important role in the brain, these cells originate from a different lineage (yolk sac) and thus are not naturally present in hiPSCs-derived neuronal culture. To study how microglia respond to diseased neurons and influence neuronal excitability, we established a co-culture model comprising hiPSC-derived neurons and microglia. We found that microglia display altered morphology with increased branch length and enhanced calcium signal when co-cultured with neurons carrying the Nav1.2-L1342P mutation. Moreover, the presence of microglia significantly lowers the action potential firing of neurons carrying the mutation. Interestingly, we further demonstrated that the current density of sodium channels in neurons carrying the epilepsy-associated mutation was reduced in the presence of microglia. Taken together, our work reveals a critical role of human iPSCs-derived microglia in sensing and dampening hyperexcitability mediated by an epilepsy-causing mutation present in human neurons, highlighting the importance of neuron-microglia interactions in human pathophysiology.
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Affiliation(s)
- Zhefu Que
- Borch Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN 47907
- Purdue Institute for Integrative Neuroscience (PIIN), Purdue University, West Lafayette, IN 47907
| | - Maria I. Olivero-Acosta
- Borch Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN 47907
- Purdue Institute for Integrative Neuroscience (PIIN), Purdue University, West Lafayette, IN 47907
| | - Ian Chen
- Borch Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN 47907
- Purdue Institute for Integrative Neuroscience (PIIN), Purdue University, West Lafayette, IN 47907
| | - Jingliang Zhang
- Borch Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN 47907
- Purdue Institute for Integrative Neuroscience (PIIN), Purdue University, West Lafayette, IN 47907
| | - Kyle Wettschurack
- Borch Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN 47907
- Purdue Institute for Integrative Neuroscience (PIIN), Purdue University, West Lafayette, IN 47907
| | - Jiaxiang Wu
- Borch Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN 47907
- Purdue Institute for Integrative Neuroscience (PIIN), Purdue University, West Lafayette, IN 47907
| | - Tiange Xiao
- Borch Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN 47907
- Purdue Institute for Integrative Neuroscience (PIIN), Purdue University, West Lafayette, IN 47907
| | - C. Max Otterbacher
- Borch Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN 47907
- Purdue Institute for Integrative Neuroscience (PIIN), Purdue University, West Lafayette, IN 47907
| | - Muhan Wang
- Borch Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN 47907
- Purdue Institute for Integrative Neuroscience (PIIN), Purdue University, West Lafayette, IN 47907
| | - Hope Harlow
- Borch Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN 47907
- Purdue Institute for Integrative Neuroscience (PIIN), Purdue University, West Lafayette, IN 47907
| | - Ningren Cui
- Borch Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN 47907
- Purdue Institute for Integrative Neuroscience (PIIN), Purdue University, West Lafayette, IN 47907
| | - Xiaoling Chen
- Borch Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN 47907
- Purdue Institute for Integrative Neuroscience (PIIN), Purdue University, West Lafayette, IN 47907
| | - Brody Deming
- Borch Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN 47907
- Purdue Institute for Integrative Neuroscience (PIIN), Purdue University, West Lafayette, IN 47907
| | - Manasi Halurkar
- Borch Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN 47907
- Purdue Institute for Integrative Neuroscience (PIIN), Purdue University, West Lafayette, IN 47907
| | - Yuanrui Zhao
- Borch Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN 47907
- Purdue Institute for Integrative Neuroscience (PIIN), Purdue University, West Lafayette, IN 47907
| | - Jean-Christophe Rochet
- Borch Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN 47907
- Purdue Institute for Integrative Neuroscience (PIIN), Purdue University, West Lafayette, IN 47907
| | - Ranjie Xu
- Purdue University College of Veterinary Medicine, West Lafayette, IN 47907
| | - Amy L. Brewster
- Department of Biological Sciences, Southern Methodist University, Dallas TX 75205
| | - Long-jun Wu
- Department of Neurology at Mayo Clinic, Rochester MN 55905
| | - Chongli Yuan
- Department of Chemical Engineering, Purdue University, West Lafayette, IN 47907
| | | | - Yang Yang
- Borch Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN 47907
- Purdue Institute for Integrative Neuroscience (PIIN), Purdue University, West Lafayette, IN 47907
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8
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Martins TG, Soliman R, Cordero-Maldonado ML, Donato C, Ameli C, Mombaerts L, Skupin A, Peri F, Crawford AD. Seizure-induced increase in microglial cell population in the developing zebrafish brain. Epilepsy Res 2023; 195:107203. [PMID: 37572541 DOI: 10.1016/j.eplepsyres.2023.107203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 06/21/2023] [Accepted: 07/31/2023] [Indexed: 08/14/2023]
Abstract
Epilepsy is a chronic brain disorder characterized by unprovoked and recurrent seizures, of which 60% are of unknown etiology. Recent studies implicate microglia in the pathophysiology of epilepsy. However, their role in this process, in particular following early-life seizures, remains poorly understood due in part to the lack of suitable experimental models allowing the in vivo imaging of microglial activity. Given the advantage of zebrafish larvae for minimally-invasive imaging approaches, we sought for the first time to describe the microglial responses after acute seizures in two different zebrafish larval models: a chemically-induced epileptic model by the systemic injection of kainate at 3 days post-fertilization, and the didys552 genetic epilepsy model, which carries a mutation in scn1lab that leads to spontaneous epileptiform discharges. Kainate-treated larvae exhibited transient brain damage as shown by increased numbers of apoptotic nuclei as early as one day post-injection, which was followed by an increase in the number of microglia in the brain. A similar microglial phenotype was also observed in didys552-/- mutants, suggesting that microglia numbers change in response to seizure-like activity in the brain. Interestingly, kainate-treated larvae also displayed a decreased seizure threshold towards subsequent pentylenetetrazole-induced seizures, as shown by higher locomotor and encephalographic activity in comparison with vehicle-injected larvae. These results are comparable to kainate-induced rodent seizure models and suggest the suitability of these zebrafish seizure models for future studies, in particular to elucidate the links between epileptogenesis and microglial dynamic changes after seizure induction in the developing brain, and to understand how these modulate seizure susceptibility.
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Affiliation(s)
- Teresa G Martins
- Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, Esch-sur-Alzette, Luxembourg.
| | - Remon Soliman
- Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | | | - Cristina Donato
- Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Corrado Ameli
- Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Laurent Mombaerts
- Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Alexander Skupin
- Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, Esch-sur-Alzette, Luxembourg; University of California, San Diego (UCSD), La Jolla, CA, United States
| | - Francesca Peri
- Developmental Biology Group, European Molecular Biology Laboratory (EMBL), Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Alexander D Crawford
- Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, Esch-sur-Alzette, Luxembourg; Institute for Orphan Drug Discovery, Bremerhaven, Germany.
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9
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Mate De Gerando A, Welikovitch LA, Khasnavis A, Commins C, Glynn C, Chun JE, Perbet R, Hyman BT. Tau seeding and spreading in vivo is supported by both AD-derived fibrillar and oligomeric tau. Acta Neuropathol 2023; 146:191-210. [PMID: 37341831 PMCID: PMC10329061 DOI: 10.1007/s00401-023-02600-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 06/12/2023] [Accepted: 06/13/2023] [Indexed: 06/22/2023]
Abstract
Insoluble fibrillar tau, the primary constituent of neurofibrillary tangles, has traditionally been thought to be the biologically active, toxic form of tau mediating neurodegeneration in Alzheimer's disease. More recent studies have implicated soluble oligomeric tau species, referred to as high molecular weight (HMW), due to their properties on size-exclusion chromatography, in tau propagation across neural systems. These two forms of tau have never been directly compared. We prepared sarkosyl-insoluble and HMW tau from the frontal cortex of Alzheimer patients and compared their properties using a variety of biophysical and bioactivity assays. Sarkosyl-insoluble fibrillar tau comprises abundant paired-helical filaments (PHF) as quantified by electron microscopy (EM) and is more resistant to proteinase K, compared to HMW tau, which is mostly in an oligomeric form. Sarkosyl-insoluble and HMW tau are nearly equivalent in potency in HEK cell bioactivity assay for seeding aggregates, and their injection reveals similar local uptake into hippocampal neurons in PS19 Tau transgenic mice. However, the HMW preparation appears to be far more potent in inducing a glial response including Clec7a-positive rod microglia in the absence of neurodegeneration or synapse loss and promotes more rapid propagation of misfolded tau to distal, anatomically connected regions, such as entorhinal and perirhinal cortices. These data suggest that soluble HMW tau has similar properties to fibrillar sarkosyl-insoluble tau with regard to tau seeding potential, but may be equal or even more bioactive with respect to propagation across neural systems and activation of glial responses, both relevant to tau-related Alzheimer phenotypes.
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Affiliation(s)
- Anastasie Mate De Gerando
- Department of Neurology, Massachusetts General Hospital, Boston, MA, USA
- Harvard Medical School, Cambridge, MA, USA
| | - Lindsay A Welikovitch
- Department of Neurology, Massachusetts General Hospital, Boston, MA, USA
- Harvard Medical School, Cambridge, MA, USA
| | - Anita Khasnavis
- Department of Neurology, Massachusetts General Hospital, Boston, MA, USA
- Harvard Medical School, Cambridge, MA, USA
| | - Caitlin Commins
- Department of Neurology, Massachusetts General Hospital, Boston, MA, USA
- Harvard Medical School, Cambridge, MA, USA
| | - Calina Glynn
- Department of Neurology, Massachusetts General Hospital, Boston, MA, USA
- Harvard Medical School, Cambridge, MA, USA
| | - Joshua E Chun
- Department of Neurology, Massachusetts General Hospital, Boston, MA, USA
- Harvard Medical School, Cambridge, MA, USA
| | - Romain Perbet
- Department of Neurology, Massachusetts General Hospital, Boston, MA, USA
- Harvard Medical School, Cambridge, MA, USA
| | - Bradley T Hyman
- Department of Neurology, Massachusetts General Hospital, Boston, MA, USA.
- Harvard Medical School, Cambridge, MA, USA.
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10
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Vasanthi SS, Rao NS, Samidurai M, Massey N, Meyer C, Gage M, Kharate M, Almanza A, Wachter L, Mafuta C, Trevino L, Carlo AM, Bryant E, Corson BE, Wohlgemuth M, Ostrander M, Showman L, Wang C, Thippeswamy T. Disease-modifying effects of a glial-targeted inducible nitric oxide synthase inhibitor (1400W) in mixed-sex cohorts of a rat soman (GD) model of epilepsy. J Neuroinflammation 2023; 20:163. [PMID: 37438764 PMCID: PMC10337207 DOI: 10.1186/s12974-023-02847-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Accepted: 07/05/2023] [Indexed: 07/14/2023] Open
Abstract
BACKGROUND Acute exposure to seizurogenic organophosphate (OP) nerve agents (OPNA) such as diisopropylfluorophosphate (DFP) or soman (GD), at high concentrations, induce immediate status epilepticus (SE), reactive gliosis, neurodegeneration, and epileptogenesis as a consequence. Medical countermeasures (MCMs-atropine, oximes, benzodiazepines), if administered in < 20 min of OPNA exposure, can control acute symptoms and mortality. However, MCMs alone are inadequate to prevent OPNA-induced brain injury and behavioral dysfunction in survivors. We have previously shown that OPNA exposure-induced SE increases the production of inducible nitric oxide synthase (iNOS) in glial cells in both short- and long- terms. Treating with a water soluble and highly selective iNOS inhibitor, 1400W, for 3 days significantly reduced OPNA-induced brain changes in those animals that had mild-moderate SE in the rat DFP model. However, such mitigating effects and the mechanisms of 1400W are unknown in a highly volatile nerve agent GD exposure. METHODS Mixed-sex cohort of adult Sprague Dawley rats were exposed to GD (132 μg/kg, s.c.) and immediately treated with atropine (2 mg/kg, i.m) and HI-6 (125 mg/kg, i.m.). Severity of seizures were quantified for an hour and treated with midazolam (3 mg/kg, i.m.). An hour post-midazolam, 1400W (20 mg/kg, i.m.) or vehicle was administered daily for 2 weeks. After behavioral testing and EEG acquisition, animals were euthanized at 3.5 months post-GD. Brains were processed for neuroinflammatory and neurodegeneration markers. Serum and CSF were used for nitrooxidative and proinflammatory cytokines assays. RESULTS We demonstrate a significant long-term (3.5 months post-soman) disease-modifying effect of 1400W in animals that had severe SE for > 20 min of continuous convulsive seizures. 1400W significantly reduced GD-induced motor and cognitive dysfunction; nitrooxidative stress (nitrite, ROS; increased GSH: GSSG); proinflammatory cytokines in the serum and some in the cerebrospinal fluid (CSF); epileptiform spikes and spontaneously recurring seizures (SRS) in males; reactive gliosis (GFAP + C3 and IBA1 + CD68-positive glia) as a measure of neuroinflammation, and neurodegeneration (especially parvalbumin-positive neurons) in some brain regions. CONCLUSION These findings demonstrate the long-term disease-modifying effects of a glial-targeted iNOS inhibitor, 1400W, in a rat GD model by modulating reactive gliosis, neurodegeneration (parvalbumin-positive neurons), and neuronal hyperexcitability.
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Affiliation(s)
- Suraj S. Vasanthi
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, 50011 USA
| | - Nikhil S. Rao
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, 50011 USA
| | - Manikandan Samidurai
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, 50011 USA
| | - Nyzil Massey
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, 50011 USA
| | - Christina Meyer
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, 50011 USA
| | - Meghan Gage
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, 50011 USA
| | - Mihir Kharate
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, 50011 USA
| | - Aida Almanza
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, 50011 USA
| | - Logan Wachter
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, 50011 USA
| | - Candide Mafuta
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, 50011 USA
| | - Lily Trevino
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, 50011 USA
| | - Adriana M. Carlo
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, 50011 USA
| | - Elijah Bryant
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, 50011 USA
| | - Brooke E. Corson
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, 50011 USA
| | - Morgan Wohlgemuth
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, 50011 USA
| | - Morgan Ostrander
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, 50011 USA
| | - Lucas Showman
- W.M. Keck Metabolomics Research Laboratory, College of Veterinary Medicine, Iowa State University, Ames, 50011 USA
| | - Chong Wang
- Department of Veterinary Diagnostic and Production Animal Medicine and Statistics, College of Veterinary Medicine, Iowa State University, Ames, 50011 USA
| | - Thimmasettappa Thippeswamy
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, 50011 USA
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11
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Beesley S, Kumar SS. The t-N-methyl-d-aspartate receptor: Making the case for d-Serine to be considered its inverse co-agonist. Neuropharmacology 2023:109654. [PMID: 37437688 DOI: 10.1016/j.neuropharm.2023.109654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 06/22/2023] [Accepted: 07/06/2023] [Indexed: 07/14/2023]
Abstract
The N-methyl-d-aspartate receptor (NMDAR) is an enigmatic macromolecule that has garnered a good deal of attention on account of its involvement in the cellular processes that underlie learning and memory, following its discovery in the mid twentieth century (Baudry and Davis, 1991). Yet, despite advances in knowledge about its function, there remains much more to be uncovered regarding the receptor's biophysical properties, subunit composition, and role in CNS physiology and pathophysiology. The motivation for this review stems from the need for synthesizing new information gathered about these receptors that sheds light on their role in synaptic plasticity and their dichotomous relationship with the amino acid d-serine through which they influence the pathogenesis of neurodegenerative diseases like temporal lobe epilepsy (TLE), the most common type of adult epilepsies (Beesley et al., 2020a). This review will outline pertinent ideas relating structure and function of t-NMDARs (GluN3 subunit-containing triheteromeric NMDARs) for which d-serine might serve as an inverse co-agonist. We will explore how tracing d-serine's origins blends glutamate-receptor biology with glial biology to help provide fresh perspectives on how neurodegeneration might interlink with neuroinflammation to initiate and perpetuate the disease state. Taken together, we envisage the review to deepen our understanding of endogenous d-serine's new role in the brain while also recognizing its therapeutic potential in the treatment of TLE that is oftentimes refractory to medications.
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Affiliation(s)
- Stephen Beesley
- Department of Biomedical Sciences, College of Medicine & Program in Neuroscience Florida State University, 1115 W. Call Street, Tallahassee, FL, 32306-4300, USA
| | - Sanjay S Kumar
- Department of Biomedical Sciences, College of Medicine & Program in Neuroscience Florida State University, 1115 W. Call Street, Tallahassee, FL, 32306-4300, USA.
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12
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Mate de Gerando A, Welikovitch LA, Khasnavis A, Commins C, Glynn C, Chun JE, Perbet R, Hyman BT. Tau seeding and spreading in vivo is supported by both AD-derived fibrillar and oligomeric tau. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.28.534418. [PMID: 37034629 PMCID: PMC10081282 DOI: 10.1101/2023.03.28.534418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Insoluble fibrillar tau, the primary constituent of neurofibrillary tangles, has traditionally been thought to be the biologically active, toxic form of tau mediating neurodegeneration in Alzheimer's disease. More recent studies have implicated soluble oligomeric tau species, referred to as high molecular weight (HMW) due to its properties on size exclusion chromatography, in tau propagation across neural systems. These two forms of tau have never been directly compared. We prepared sarkosyl insoluble and HMW tau from the frontal cortex of Alzheimer patients and compared their properties using a variety of biophysical and bioactivity assays. Sarkosyl insoluble fibrillar tau is comprised of abundant paired helical filaments (PHF) as quantified by electron microscopy (EM), and is more resistant to proteinase K, compared to HMW tau which is mostly in an oligomeric form. Sarkosyl insoluble and HMW tau are nearly equivalent in potency in a HEK cell bioactivity assay for seeding aggregates and their injection reveals similar local uptake into hippocampal neurons in PS19 Tau transgenic mice. However, the HMW preparation appears to be far more potent in inducing a glial response including Clec7a-positive rod-microglia in the absence of neurodegeneration or synapse loss and promotes more rapid propagation of misfolded tau to distal, anatomically connected regions, such as entorhinal and perirhinal cortices. These data suggest that soluble HMW tau has similar properties to fibrillar sarkosyl insoluble tau with regard to tau seeding potential but may be equal or even more bioactive with respect to propagation across neural systems and activation of glial responses, both relevant tau-related Alzheimer phenotypes.
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13
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Vasanthi SS, Rao NS, Samidurai M, Massey N, Meyer C, Gage M, Kharate M, Almanza A, Wachter L, Mafuta C, Trevino L, Carlo AM, Bryant E, Corson BE, Wohlgemuth M, Ostrander M, Wang C, Thippeswamy T. Disease-Modifying Effects of a Glial-targeted Inducible Nitric Oxide Synthase Inhibitor (1400W) in Mixed-sex Cohorts of a Rat Soman (GD) Model of Epilepsy. RESEARCH SQUARE 2023:rs.3.rs-2883247. [PMID: 37214912 PMCID: PMC10197763 DOI: 10.21203/rs.3.rs-2883247/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Background Acute exposure to seizurogenic organophosphate (OP) nerve agents (OPNA) such as diisopropylfluorophosphate (DFP) or soman (GD), at high concentrations, induce immediate status epilepticus (SE), reactive gliosis, neurodegeneration, and epileptogenesis as a consequence. Medical countermeasures (MCMs- atropine, oximes, benzodiazepines), if administered in < 20 minutes of OPNA exposure, can control acute symptoms and mortality. However, MCMs alone are inadequate to prevent OPNA-induced brain injury and behavioral dysfunction in survivors. We have previously shown that OPNA exposure-induced SE increases the production of inducible nitric oxide synthase (iNOS) in glial cells in both short- and long- terms. Treating with a water soluble and highly selective iNOS inhibitor, 1400W, for three days significantly reduced OPNA-induced brain changes in those animals that had mild-moderate SE in the rat DFP model. However, such mitigating effects and the mechanisms of 1400W are unknown in a highly volatile nerve agent GD exposure. Methods Mixed-sex cohort of adult Sprague Dawley rats were exposed to GD (132µg/kg, s.c.) and immediately treated with atropine (2mg/kg, i.m) and HI-6 (125mg/kg, i.m.). Severity of seizures were quantified for an hour and treated with midazolam (3mg/kg, i.m.). An hour post-midazolam, 1400W (20mg/kg, i.m.) or vehicle was administered daily for two weeks. After behavioral testing and EEG acquisition, animals were euthanized at 3.5 months post-GD. Brains were processed for neuroinflammatory and neurodegeneration markers. Serum and CSF were used for nitrooxidative and proinflammatory cytokines assays. Results We demonstrate a significant long-term (3.5 months post-soman) disease-modifying effect of 1400W in animals that had severe SE for > 20min of continuous convulsive seizures. 1400W significantly reduced GD-induced motor and cognitive dysfunction; nitrooxidative stress (nitrite, ROS; increased GSH: GSSG); proinflammatory cytokines in the serum and some in the cerebrospinal fluid (CSF); epileptiform spikes and spontaneously recurring seizures (SRS) in males; reactive gliosis (GFAP + C3 and IBA1 + CD68 positive glia) as a measure of neuroinflammation, and neurodegeneration (including parvalbumin positive neurons) in some brain regions. Conclusion These findings demonstrate the long-term disease-modifying effects of a glial-targeted iNOS inhibitor, 1400W, in a rat GD model by modulating reactive gliosis, neurodegeneration, and neuronal hyperexcitability.
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14
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Surina NM, Fedotova IB, Nikolaev GM, Grechenko VV, Gankovskaya LV, Ogurtsova AD, Poletaeva II. Neuroinflammation in Pathogenesis of Audiogenic Epilepsy: Altered Proinflammatory Cytokine Levels in the Rats of Krushinsky-Molodkina Seizure-Prone Strain. BIOCHEMISTRY. BIOKHIMIIA 2023; 88:481-490. [PMID: 37080934 DOI: 10.1134/s0006297923040041] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/22/2023]
Abstract
Neuroinflammation plays an important role in epileptogenesis, however, most studies are performed using pharmacological models of epilepsy, while there are only few data available for non-invasive, including genetic, models. The levels of a number of pro-inflammatory cytokines were examined in the Krushinsky-Molodkina (KM) rat strain with high audiogenic epilepsy (AE) proneness (intense tonic seizure fit in response to loud sound) and in the control strain "0" (not predisposed to AE) using multiplex immunofluorescence magnetic assay (MILLIPLEX map Kit). Cytokine levels were determined in the dorsal striatum tissue and in the brain stem. Background levels of IL-1β, IL-6, and TNF-α in the dorsal striatum of the KM rats were significantly lower than in the rats "0" (by 32.31, 27.84, and 38.87%, respectively, p < 0.05, 0.05, and 0.01), whereas no inter-strain differences in the levels of these metabolites were detected in the brain stem in the "background" state. Four hours after sound exposure, the TNF-α level in the dorsal striatum of the KM rats was significantly lower (by 38.34%, p < 0.01) than in the "0" rats. In the KM rats, the dorsal striatal levels of IL-1β and IL-6 were significantly higher after the sound exposure and subsequent seizure fit, compared to the background (35.29 and 50.21% increase, p < 0.05, 0.01, respectively). In the background state the IL-2 level in the KM rats was not detected, whereas after audiogenic seizures its level was 14.01 pg/ml (significant difference, p < 0.01). In the KM rats the brain stem levels of IL-1β and TNF-α after audiogenic seizures were significantly lower than in the background (13.23 and 23.44% decrease, respectively, p < 0.05). In the rats of the "0" strain, the levels of cytokines in the dorsal striatum after the action of sound (which did not induce AE seizures) were not different from those of the background, while in the brain stem of the "0" strain the levels of IL-1β were lower than in the background (40.28%, p < 0.01). Thus, the differences between the background levels of cytokines and those after the action of sound were different in the rats with different proneness to AE. These data suggest involvement of the analyzed cytokines in pathophysiology of the seizure state, namely in AE seizures.
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Affiliation(s)
- Natalia M Surina
- Faculty of Biology, Lomonosov Moscow State University, Moscow, 119234, Russia.
| | - Irina B Fedotova
- Faculty of Biology, Lomonosov Moscow State University, Moscow, 119234, Russia
| | - Georgy M Nikolaev
- Faculty of Biology, Lomonosov Moscow State University, Moscow, 119234, Russia
| | | | | | | | - Inga I Poletaeva
- Faculty of Biology, Lomonosov Moscow State University, Moscow, 119234, Russia.
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15
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Wyatt-Johnson SK, Kersey HN, Codocedo JF, Newell KL, Landreth GE, Lamb BT, Oblak AL, Brutkiewicz RR. Control of the temporal development of Alzheimer's disease pathology by the MR1/MAIT cell axis. J Neuroinflammation 2023; 20:78. [PMID: 36944969 PMCID: PMC10029194 DOI: 10.1186/s12974-023-02761-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Accepted: 03/10/2023] [Indexed: 03/23/2023] Open
Abstract
BACKGROUND Neuroinflammation is an important feature of Alzheimer's disease (AD). Understanding which aspects of the immune system are important in AD may lead to new therapeutic approaches. We study the major histocompatibility complex class I-related immune molecule, MR1, which is recognized by an innate-like T cell population called mucosal-associated invariant T (MAIT) cells. METHODS Having found that MR1 gene expression is elevated in the brain tissue of AD patients by mining the Agora database, we sought to examine the role of the MR1/MAIT cell axis in AD pathology. Brain tissue from AD patients and the 5XFAD mouse model of AD were used to analyze MR1 expression through qPCR, immunofluorescence, and flow cytometry. Furthermore, mice deficient in MR1 and MAIT cells were crossed with the 5XFAD mice to produce a model to study how the loss of this innate immune axis alters AD progression. Moreover, 5XFAD mice were also used to study brain-resident MAIT cells over time. RESULTS In tissue samples from AD patients and 5XFAD mice, MR1 expression was substantially elevated in the microglia surrounding plaques vs. those that are further away (human AD: P < 0.05; 5XFAD: P < 0.001). In 5XFAD mice lacking the MR1/MAIT cell axis, the development of amyloid-beta plaque pathology occurred at a significantly slower rate than in those mice with MR1 and MAIT cells. Furthermore, in brain tissue from 5XFAD mice, there was a temporal increase in MAIT cell numbers (P < 0.01) and their activation state, the latter determined by detecting an upregulation of both CD69 (P < 0.05) and the interleukin-2 receptor alpha chain (P < 0.05) via flow cytometry. CONCLUSIONS Together, these data reveal a previously unknown role for the MR1/MAIT cell innate immune axis in AD pathology and its potential utility as a novel therapeutic target.
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Affiliation(s)
- Season K Wyatt-Johnson
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, IN, 46202, USA
- Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN, 46202, USA
| | - Holly N Kersey
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, IN, 46202, USA
| | - Juan F Codocedo
- Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN, 46202, USA
- Department of Anatomy, Cell Biology and Physiology, Indiana University School of Medicine, Indianapolis, IN, 46202, USA
| | - Kathy L Newell
- Department of Pathology and Laboratory Medicine, Indiana University School of Medicine, Indianapolis, IN, 46202, USA
- Department of Neurology, Indiana University School of Medicine, Indianapolis, IN, 46202, USA
| | - Gary E Landreth
- Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN, 46202, USA
- Department of Anatomy, Cell Biology and Physiology, Indiana University School of Medicine, Indianapolis, IN, 46202, USA
| | - Bruce T Lamb
- Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN, 46202, USA
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN, 46202, USA
| | - Adrian L Oblak
- Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN, 46202, USA
- Department of Radiology and Imaging Sciences, Indiana University School of Medicine, Indianapolis, IN, 46202, USA
| | - Randy R Brutkiewicz
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, IN, 46202, USA.
- Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN, 46202, USA.
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16
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Basurco L, Abellanas MA, Ayerra L, Conde E, Vinueza-Gavilanes R, Luquin E, Vales A, Vilas A, Martin-Uriz PS, Tamayo I, Alonso MM, Hernaez M, Gonzalez-Aseguinolaza G, Clavero P, Mengual E, Arrasate M, Hervás-Stubbs S, Aymerich MS. Microglia and astrocyte activation is region-dependent in the α-synuclein mouse model of Parkinson's disease. Glia 2023; 71:571-587. [PMID: 36353934 PMCID: PMC10100513 DOI: 10.1002/glia.24295] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 10/16/2022] [Accepted: 10/21/2022] [Indexed: 11/11/2022]
Abstract
Inflammation is a common feature in neurodegenerative diseases that contributes to neuronal loss. Previously, we demonstrated that the basal inflammatory tone differed between brain regions and, consequently, the reaction generated to a pro-inflammatory stimulus was different. In this study, we assessed the innate immune reaction in the midbrain and in the striatum using an experimental model of Parkinson's disease. An adeno-associated virus serotype 9 expressing the α-synuclein and mCherry genes or the mCherry gene was administered into the substantia nigra. Myeloid cells (CD11b+ ) and astrocytes (ACSA2+ ) were purified from the midbrain and striatum for bulk RNA sequencing. In the parkinsonian midbrain, CD11b+ cells presented a unique anti-inflammatory transcriptomic profile that differed from degenerative microglia signatures described in experimental models for other neurodegenerative conditions. By contrast, striatal CD11b+ cells showed a pro-inflammatory state and were similar to disease-associated microglia. In the midbrain, a prominent increase of infiltrated monocytes/macrophages was observed and, together with microglia, participated actively in the phagocytosis of dopaminergic neuronal bodies. Although striatal microglia presented a phagocytic transcriptomic profile, morphology and cell density was preserved and no active phagocytosis was detected. Interestingly, astrocytes presented a pro-inflammatory fingerprint in the midbrain and a low number of differentially displayed transcripts in the striatum. During α-synuclein-dependent degeneration, microglia and astrocytes experience context-dependent activation states with a different contribution to the inflammatory reaction. Our results point towards the relevance of selecting appropriate cell targets to design neuroprotective strategies aimed to modulate the innate immune system during the active phase of dopaminergic degeneration.
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Affiliation(s)
- Leyre Basurco
- Departamentode Bioquímica y Genética, Facultad de Ciencias, Universidad de Navarra, Pamplona, Spain.,Programa de Neurociencias, CIMA-Universidad de Navarra, Pamplona, Spain
| | - Miguel Angel Abellanas
- Departamentode Bioquímica y Genética, Facultad de Ciencias, Universidad de Navarra, Pamplona, Spain.,Programa de Neurociencias, CIMA-Universidad de Navarra, Pamplona, Spain
| | - Leyre Ayerra
- Departamentode Bioquímica y Genética, Facultad de Ciencias, Universidad de Navarra, Pamplona, Spain.,Programa de Neurociencias, CIMA-Universidad de Navarra, Pamplona, Spain
| | - Enrique Conde
- Programa de Inmunología, CIMA-Universidad de Navarra, Pamplona, Spain
| | | | - Esther Luquin
- Departamento de Patología, Anatomía y Fisiología, Facultad de Medicina, Universidad de Navarra, Pamplona, Spain
| | - Africa Vales
- Programa de Terapia Génica, CIMA-Universidad de Navarra, Pamplona, Spain
| | - Amaya Vilas
- Programa de Oncohematología, CIMA-Universidad de Navarra, Pamplona, Spain
| | | | - Ibon Tamayo
- Programa de Biología Computacional, CIMA-Universidad de Navarra, Pamplona, Spain
| | - Marta M Alonso
- Programa de Tumores Sólidos, CIMA-Universidad de Navarra, Pamplona, Spain.,Neurociencias y Salud Mental, Instituto de Investigación Sanitaria de Navarra (IdiSNA), Spain
| | - Mikel Hernaez
- Programa de Biología Computacional, CIMA-Universidad de Navarra, Pamplona, Spain
| | - Gloria Gonzalez-Aseguinolaza
- Programa de Terapia Génica, CIMA-Universidad de Navarra, Pamplona, Spain.,Neurociencias y Salud Mental, Instituto de Investigación Sanitaria de Navarra (IdiSNA), Spain
| | - Pedro Clavero
- Servicio de Neurología, Complejo Hospitalario de Navarra, Pamplona, Spain
| | - Elisa Mengual
- Departamento de Patología, Anatomía y Fisiología, Facultad de Medicina, Universidad de Navarra, Pamplona, Spain
| | - Montserrat Arrasate
- Programa de Neurociencias, CIMA-Universidad de Navarra, Pamplona, Spain.,Neurociencias y Salud Mental, Instituto de Investigación Sanitaria de Navarra (IdiSNA), Spain
| | - Sandra Hervás-Stubbs
- Programa de Inmunología, CIMA-Universidad de Navarra, Pamplona, Spain.,Neurociencias y Salud Mental, Instituto de Investigación Sanitaria de Navarra (IdiSNA), Spain
| | - Maria S Aymerich
- Departamentode Bioquímica y Genética, Facultad de Ciencias, Universidad de Navarra, Pamplona, Spain.,Programa de Neurociencias, CIMA-Universidad de Navarra, Pamplona, Spain.,Programa de Tumores Sólidos, CIMA-Universidad de Navarra, Pamplona, Spain.,Neurociencias y Salud Mental, Instituto de Investigación Sanitaria de Navarra (IdiSNA), Spain
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17
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Jia X, Wang Q, Ji J, Lu W, Liu Z, Tian H, Guo L, Wang Y. Mitochondrial transplantation ameliorates hippocampal damage following status epilepticus. Animal Model Exp Med 2023; 6:41-50. [PMID: 36734302 PMCID: PMC9986225 DOI: 10.1002/ame2.12310] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Accepted: 12/30/2022] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND Hippocampal damage caused by status epilepticus (SE) can bring about cognitive decline and emotional disorders, which are common clinical comorbidities in patients with epilepsy. It is therefore imperative to develop a novel therapeutic strategy for protecting hippocampal damage after SE. Mitochondrial dysfunction is one of contributing factors in epilepsy. Given the therapeutic benefits of mitochondrial replenishment by exogenous mitochondria, we hypothesized that transplantation of mitochondria would be capable of ameliorating hippocampal damage following SE. METHODS Pilocarpine was used to induced SE in mice. SE-generated cognitive decline and emotional disorders were determined using novel object recognition, the tail suspension test, and the open field test. SE-induced hippocampal pathology was assessed by quantifying loss of neurons and activation of microglia and astrocytes. The metabolites underlying mitochondrial transplantation were determined using metabonomics. RESULTS The results showed that peripheral administration of isolated mitochondria could improve cognitive deficits and depressive and anxiety-like behaviors. Exogenous mitochondria blunted the production of reactive oxygen species, proliferation of microglia and astrocytes, and loss of neurons in the hippocampus. The metabonomic profiles showed that mitochondrial transplantation altered multiple metabolic pathways such as sphingolipid signaling pathway and carbon metabolism. Among potential affected metabolites, mitochondrial transplantation decreased levels of sphingolipid (d18:1/18:0) and methylmalonic acid, and elevated levels of D-fructose-1,6-bisphosphate. CONCLUSION To the best of our knowledge, these findings provide the first direct experimental evidence that artificial mitochondrial transplantation is capable of ameliorating hippocampal damage following SE. These new findings support mitochondrial transplantation as a promising therapeutic strategy for epilepsy-associated psychiatric and cognitive disorders.
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Affiliation(s)
- Xiaoxia Jia
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical University, Xuzhou, China
| | - Qinghua Wang
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical University, Xuzhou, China
| | - Jianlun Ji
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical University, Xuzhou, China
| | - Wenchun Lu
- Psychology Laboratory, School of Management, Xuzhou Medical University, Xuzhou, China
| | - Zhidong Liu
- Department of Pharmacy, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
| | - Hao Tian
- Agro-Products Processing Research Institute, Yunnan Academy of Agricultural Sciences, Kunming, China
| | - Lin Guo
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical University, Xuzhou, China.,Department of Pharmacy, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
| | - Yun Wang
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical University, Xuzhou, China
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18
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Henning L, Antony H, Breuer A, Müller J, Seifert G, Audinat E, Singh P, Brosseron F, Heneka MT, Steinhäuser C, Bedner P. Reactive microglia are the major source of tumor necrosis factor alpha and contribute to astrocyte dysfunction and acute seizures in experimental temporal lobe epilepsy. Glia 2023; 71:168-186. [PMID: 36373840 DOI: 10.1002/glia.24265] [Citation(s) in RCA: 19] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 08/12/2022] [Accepted: 08/17/2022] [Indexed: 11/09/2022]
Abstract
Extensive microglia reactivity has been well described in human and experimental temporal lobe epilepsy (TLE). To date, however, it is not clear whether and based on which molecular mechanisms microglia contribute to the development and progression of focal epilepsy. Astroglial gap junction coupled networks play an important role in regulating neuronal activity and loss of interastrocytic coupling causally contributes to TLE. Here, we show in the unilateral intracortical kainate (KA) mouse model of TLE that reactive microglia are primary producers of tumor necrosis factor (TNF)α and contribute to astrocyte dysfunction and severity of status epilepticus (SE). Immunohistochemical analyses revealed pronounced and persistent microglia reactivity, which already started 4 h after KA-induced SE. Partial depletion of microglia using a colony stimulating factor 1 receptor inhibitor prevented early astrocyte uncoupling and attenuated the severity of SE, but increased the mortality of epileptic mice following surgery. Using microglia-specific inducible TNFα knockout mice we identified microglia as the major source of TNFα during early epileptogenesis. Importantly, microglia-specific TNFα knockout prevented SE-induced gap junction uncoupling in astrocytes. Continuous telemetric EEG recordings revealed that during the first 4 weeks after SE induction, microglial TNFα did not significantly contribute to spontaneous generalized seizure activity. Moreover, the absence of microglial TNFα did not affect the development of hippocampal sclerosis but attenuated gliosis. Taken together, these data implicate reactive microglia in astrocyte dysfunction and network hyperexcitability after an epileptogenic insult.
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Affiliation(s)
- Lukas Henning
- Institute of Cellular Neurosciences, Medical Faculty, University of Bonn, Bonn, Germany
| | - Henrike Antony
- Institute of Cellular Neurosciences, Medical Faculty, University of Bonn, Bonn, Germany
| | - Annika Breuer
- Institute of Cellular Neurosciences, Medical Faculty, University of Bonn, Bonn, Germany
| | - Julia Müller
- Institute of Cellular Neurosciences, Medical Faculty, University of Bonn, Bonn, Germany
| | - Gerald Seifert
- Institute of Cellular Neurosciences, Medical Faculty, University of Bonn, Bonn, Germany
| | - Etienne Audinat
- Institute of Functional Genomics, University of Montpellier, CNRS, INSERM, Montpellier, France
| | | | | | | | - Christian Steinhäuser
- Institute of Cellular Neurosciences, Medical Faculty, University of Bonn, Bonn, Germany
| | - Peter Bedner
- Institute of Cellular Neurosciences, Medical Faculty, University of Bonn, Bonn, Germany
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19
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Challa SR, Nalamolu KR, Fornal CA, Mohandass A, Mussman JP, Schaibley C, Kashyap A, Sama V, Wang BC, Klopfenstein JD, Pinson DM, Kunamneni A, Veeravalli KK. The interplay between MMP-12 and t-PA in the brain after ischemic stroke. Neurochem Int 2022; 161:105436. [PMID: 36283468 PMCID: PMC9898869 DOI: 10.1016/j.neuint.2022.105436] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 10/17/2022] [Accepted: 10/18/2022] [Indexed: 11/05/2022]
Abstract
Tissue-type plasminogen activator (t-PA) expression is known to increase following transient focal cerebral ischemia and reperfusion. Previously, we reported downregulation of t-PA upon suppression of matrix metalloproteinase-12 (MMP-12), following transient focal cerebral ischemia and reperfusion. We now present data on the temporal expression of t-PA in the brain after transient ischemia, as well as the interaction between MMP-12 and t-PA, two proteases associated with the breakdown of the blood-brain barrier (BBB) and ischemic brain damage. We hypothesized that there might be reciprocal interactions between MMP-12 and t-PA in the brain after ischemic stroke. This hypothesis was tested using shRNA-mediated gene silencing and computational modeling. Suppression of t-PA following transient ischemia and reperfusion in rats attenuated MMP-12 expression in the brain. The overall effect of t-PA shRNA administration was to attenuate the degradation of BBB tight junction protein claudin-5, diminish BBB disruption, and reduce neuroinflammation by decreasing the expression of the microglia/macrophage pro-inflammatory M1 phenotype (CD68, iNOS, IL-1β, and TNFα). Reduced BBB disruption and subsequent lack of infiltration of macrophages (the main source of MMP-12 in the ischemic brain) could account for the decrease in MMP-12 expression after t-PA suppression. Computational modeling of in silico protein-protein interactions indicated that MMP-12 and t-PA may interact physically. Overall, our findings demonstrate that MMP-12 and t-PA interact directly or indirectly at multiple levels in the brain following an ischemic stroke. The present findings could be useful in the development of new pharmacotherapies for the treatment of stroke.
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Affiliation(s)
- Siva Reddy Challa
- Department of Cancer Biology and Pharmacology, University of Illinois College of Medicine at Peoria, Peoria, IL, USA; Department of Pharmacology, KVSR Siddhartha College of Pharmaceutical Sciences, Vijayawada, Andhra Pradesh, India
| | - Koteswara Rao Nalamolu
- Department of Cancer Biology and Pharmacology, University of Illinois College of Medicine at Peoria, Peoria, IL, USA
| | - Casimir A Fornal
- Department of Cancer Biology and Pharmacology, University of Illinois College of Medicine at Peoria, Peoria, IL, USA
| | - Adithya Mohandass
- Department of Cancer Biology and Pharmacology, University of Illinois College of Medicine at Peoria, Peoria, IL, USA
| | - Justin P Mussman
- Department of Cancer Biology and Pharmacology, University of Illinois College of Medicine at Peoria, Peoria, IL, USA
| | - Claire Schaibley
- Department of Cancer Biology and Pharmacology, University of Illinois College of Medicine at Peoria, Peoria, IL, USA
| | - Aanan Kashyap
- Department of Cancer Biology and Pharmacology, University of Illinois College of Medicine at Peoria, Peoria, IL, USA
| | - Vinay Sama
- Department of Cancer Biology and Pharmacology, University of Illinois College of Medicine at Peoria, Peoria, IL, USA
| | - Billy C Wang
- Department of Cancer Biology and Pharmacology, University of Illinois College of Medicine at Peoria, Peoria, IL, USA; Department of Pediatrics, University of Illinois College of Medicine at Peoria, Peoria, IL, USA; Children's Hospital of Illinois, OSF HealthCare Saint Francis Medical Center, Peoria, IL, USA
| | - Jeffrey D Klopfenstein
- Department of Cancer Biology and Pharmacology, University of Illinois College of Medicine at Peoria, Peoria, IL, USA; Department of Neurosurgery, University of Illinois College of Medicine at Peoria, Peoria, IL, USA; Illinois Neurological Institute, OSF HealthCare Saint Francis Medical Center, Peoria, IL, USA
| | - David M Pinson
- Department of Health Sciences Education and Pathology, University of Illinois College of Medicine at Peoria, Peoria, IL, USA
| | | | - Krishna Kumar Veeravalli
- Department of Cancer Biology and Pharmacology, University of Illinois College of Medicine at Peoria, Peoria, IL, USA; Department of Pediatrics, University of Illinois College of Medicine at Peoria, Peoria, IL, USA; Department of Neurosurgery, University of Illinois College of Medicine at Peoria, Peoria, IL, USA; Department of Neurology, University of Illinois College of Medicine at Peoria, Peoria, IL, USA.
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20
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Xie R, Zhao W, Lowe S, Bentley R, Hu G, Mei H, Jiang X, Sun C, Wu Y, Yueying Liu. Quercetin alleviates kainic acid-induced seizure by inhibiting the Nrf2-mediated ferroptosis pathway. Free Radic Biol Med 2022; 191:212-226. [PMID: 36087883 DOI: 10.1016/j.freeradbiomed.2022.09.001] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/11/2022] [Revised: 08/28/2022] [Accepted: 09/03/2022] [Indexed: 02/07/2023]
Abstract
BACKGROUND Epilepsy is one of the most common neurological disorders in childhood. However, classical antiepileptic drugs are linked with drug toxicity and cognitive function impairment in children. Hence, it is essential to develop a novel therapy to solve this problem. Currently, studies indicate regulating the nuclear factor-erythroid 2-related factor 2 (Nrf2)-mediated ferroptosis pathway represents a potential advanced therapy for seizures. Hence, the present study aimed to explore whether quercetin, a natural polyphenol, could alleviate seizure-induced neuron death and preserve cognitive function by inhibiting Nrf2-mediated ferroptosis. METHODS Kainic acid-induced epileptic mice model, morris water maze (MWM) test, cell counting kit-8 (CCK-8) assays, western blotting analysis, enzyme-linked immunosorbent assay, flow cytometry, quantitative real-time reverse transcription PCR (qRT-PCR), immunofluorescence staining, and RNA sequencing analysis were employed to explore the potential mechanisms by which quercetin exerts protective effects on seizure-induced neuron death in kainic acid-induced epileptic mice model and glutamate-induced HT22 neuronal cell death. RESULTS Our findings suggested the association between the Nrf2-mediated ferroptosis pathway and seizures in a clinical setting. Quercetin pretreatment alleviates seizure-like behaviors and cognitive impairment in KA-induced epileptic mice. Additionally, in vitro, co-treatment with quercetin effectively exerts neuroprotective effects in glutamate-induced HT22 neuronal cell death. These protective effects were also closely linked to regulating the Nrf2-mediated ferroptosis pathway. Furthermore, bioinformatic profiling revealed that the SIRT1/Nrf2/SLC7A11/GPX4 pathway plays a crucial role in the Glu-induced HT22 cell death pretreated with quercetin. CONCLUSIONS These findings indicated that quercetin effectively protects against seizure-induced neuron death in vivo and in vitro and alleviates cognitive function impairment via the SIRT1/Nrf2/SLC7A11/GPX4 pathway.
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Affiliation(s)
- Ruijin Xie
- Jiangnan University, School of Medicine, Wuxi, China; Affiliated Hospital of Jiangnan University, Department of Pediatrics, Wuxi, China
| | - Wenjing Zhao
- Jiangnan University, School of Medicine, Wuxi, China; Affiliated Northern Jiangsu People's Hospital of Yangzhou University, Yangzhou, China
| | - Scott Lowe
- Kansas City University, College of Osteopathic Medicine, Kansas City, USA
| | - Rachel Bentley
- Kansas City University, College of Osteopathic Medicine, Kansas City, USA
| | - Guoqin Hu
- Jiangnan University, School of Medicine, Wuxi, China; Affiliated Hospital of Jiangnan University, Department of Pediatrics, Wuxi, China
| | - Huiya Mei
- Jiangnan University, School of Medicine, Wuxi, China; Affiliated Hospital of Jiangnan University, Department of Pediatrics, Wuxi, China
| | - Xiaofan Jiang
- Jiangnan University, School of Medicine, Wuxi, China; Affiliated Hospital of Jiangnan University, Department of Pediatrics, Wuxi, China
| | - Chenyu Sun
- AMITA Health Saint Joseph Hospital, Chicago, USA.
| | - Yu Wu
- Jiangnan University, School of Medicine, Wuxi, China.
| | - Yueying Liu
- Jiangnan University, School of Medicine, Wuxi, China; Affiliated Hospital of Jiangnan University, Department of Pediatrics, Wuxi, China.
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21
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Mo Y, Xu W, Fu K, Chen H, Wen J, Huang Q, Guo F, Mo L, Yan J. The dual function of microglial polarization and its treatment targets in ischemic stroke. Front Neurol 2022; 13:921705. [PMID: 36212660 PMCID: PMC9538667 DOI: 10.3389/fneur.2022.921705] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2022] [Accepted: 07/14/2022] [Indexed: 11/23/2022] Open
Abstract
Stroke is the leading cause of disability and death worldwide, with ischemic stroke occurring in ~5% of the global population every year. Recently, many studies have been conducted on the inflammatory response after stroke. Microglial/macrophage polarization has a dual function and is critical to the pathology of ischemic stroke. Microglial/macrophage activation is important in reducing neuronal apoptosis, enhancing neurogenesis, and promoting functional recovery after ischemic stroke. In this review, we investigate the physiological characteristics and functions of microglia in the brain, the activation and phenotypic polarization of microglia and macrophages after stroke, the signaling mechanisms of polarization states, and the contribution of microglia to brain pathology and repair. We summarize recent advances in stroke-related microglia research, highlighting breakthroughs in therapeutic strategies for microglial responses after stroke, thereby providing new ideas for the treatment of ischemic stroke.
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Affiliation(s)
- Yong Mo
- Department of Neurosurgery, Guangxi Medical University Cancer Hospital, Nanning, China
| | - Weilin Xu
- Department of Neurosurgery, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Kaijing Fu
- Department of Neurosurgery, Guangxi Medical University Cancer Hospital, Nanning, China
| | - Hainan Chen
- Department of Neurosurgery, Guangxi Medical University Cancer Hospital, Nanning, China
| | - Jing Wen
- Department of Rheumatism, First Affiliated Hospital of Guangxi Medical University, Nanning, China
| | - Qianrong Huang
- Department of Neurosurgery, Guangxi Medical University Cancer Hospital, Nanning, China
| | - Fangzhou Guo
- Department of Neurosurgery, Guangxi Medical University Cancer Hospital, Nanning, China
| | - Ligen Mo
- Department of Neurosurgery, Guangxi Medical University Cancer Hospital, Nanning, China
- Ligen Mo
| | - Jun Yan
- Department of Neurosurgery, Guangxi Medical University Cancer Hospital, Nanning, China
- *Correspondence: Jun Yan
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22
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Characterisation of NLRP3 pathway-related neuroinflammation in temporal lobe epilepsy. PLoS One 2022; 17:e0271995. [PMID: 35972937 PMCID: PMC9380933 DOI: 10.1371/journal.pone.0271995] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Accepted: 07/11/2022] [Indexed: 11/24/2022] Open
Abstract
Objective Inflammation of brain structures, in particular the hippocampal formation, can induce neuronal degeneration and be associated with increased excitability manifesting as propensity for repetitive seizures. An increase in the abundance of individual proinflammatory molecules including interleukin 1 beta has been observed in brain tissue samples of patients with pharmacoresistant temporal lobe epilepsy (TLE) and corresponding animal models. The NLRP3-inflammasome, a cytosolic protein complex, acts as a key regulator in proinflammatory innate immune signalling. Upon activation, it leads to the release of interleukin 1 beta and inflammation-mediated neurodegeneration. Transient brain insults, like status epilepticus (SE), can render hippocampi chronically hyperexcitable and induce segmental neurodegeneration. The underlying mechanisms are referred to as epileptogenesis. Here, we have tested the hypothesis that distinct NLRP3-dependent transcript and protein signalling dynamics are induced by SE and whether they differ between two classical SE models. We further correlated the association of NLRP3-related transcript abundance with convulsive activity in human TLE hippocampi of patients with and without associated neurodegenerative damage. Methods Hippocampal mRNA- and protein-expression of NLRP3 and associated signalling molecules were analysed longitudinally in pilocarpine- and kainic acid-induced SE TLE mouse models. Complementarily, we studied NLRP3 inflammasome-associated transcript patterns in epileptogenic hippocampi with different damage patterns of pharmacoresistant TLE patients that had undergone epilepsy surgery for seizure relief. Results Pilocarpine- and kainic acid-induced SE elicit distinct hippocampal Nlrp3-associated molecular signalling. Transcriptional activation of NLRP3 pathway elements is associated with seizure activity but independent of the particular neuronal damage phenotype in KA-induced and in human TLE hippocampi. Significance These data suggest highly dynamic inflammasome signalling in SE-induced TLE and highlight a vicious cycle associated with seizure activity. Our results provide promising perspectives for the inflammasome signalling pathway as a target for anti-epileptogenic and -convulsive therapeutic strategies. The latter may even applicable to a particularly broad spectrum of TLE patients with currently pharmacoresistant disease.
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23
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Narvaiz DA, Sullens DG, Santana-Coelho D, Lugo JN. Neuronal subset-specific phosphatase and tensin homolog knockout mice exhibit age and brain region-associated alterations in microglia/macrophage activation. Neuroreport 2022; 33:476-480. [PMID: 35775322 PMCID: PMC9479702 DOI: 10.1097/wnr.0000000000001808] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Seizures induce brain region-dependent enhancements in microglia/macrophage activation. Neuronal subset-specific phosphatase and tensin homolog (PTEN) knockout (KO) mice display hyperactive mammalian target of rapamycin (mTOR) signaling in the hippocampus, cerebellum, and cortex followed by seizures that increase in severity with age. To determine if KO mice also exhibit alterations in the spatiotemporal activation pattern of microglia, we used flow cytometry to compare the percentage of major histocompatibility complex-II activated microglia/macrophages between KO and wildtype (WT) mice at 5, 10, and 15 weeks of age. At 5 weeks, microglia/macrophage activation was greater in the cortex, P < 0.001, cerebellum, P < 0.001, and hippocampus, P < 0.001, of KO compared to WT mice. At 10 weeks, activation was greatest in the cortex of KO mice, P < 0.001, in the cerebellum of WT mice, P < 0.001, but similar in the hippocampus, P > 0.05. By 15 weeks, activation in the hippocampus was more than 25 times greater in KO mice compared to WT mice, P < 0.001. We show that hyperactive mTOR signaling is associated with an altered spatiotemporal pattern of microglia/macrophage activation in the brain and induces an enhanced neuroimmune response in the hippocampus.
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Affiliation(s)
- David A. Narvaiz
- Department of Psychology and Neuroscience, Baylor University, Waco, TX, 76798 USA
| | - D. Gregory Sullens
- Department of Psychology and Neuroscience, Baylor University, Waco, TX, 76798 USA
| | | | - Joaquin N. Lugo
- Department of Psychology and Neuroscience, Baylor University, Waco, TX, 76798 USA
- Department of Biology, Baylor University, Waco, TX, 76798 USA
- Institute of Biomedical Studies, Baylor University, Waco, TX, 76798 USA
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24
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Herr SA, Gardeen SS, Low PS, Shi R. Targeted delivery of acrolein scavenger hydralazine in spinal cord injury using folate-linker-drug conjugation. Free Radic Biol Med 2022; 184:66-73. [PMID: 35398493 DOI: 10.1016/j.freeradbiomed.2022.04.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 03/30/2022] [Accepted: 04/03/2022] [Indexed: 11/26/2022]
Abstract
Oxidative stress has been shown to play a critical pathogenic role in functional loss after spinal cord injury (SCI). As a direct result of oxidative stress, lipid peroxidation-derived aldehydes have emerged as key culprits that sustain secondary injury and contribute significantly to pathological outcomes. Acrolein, a neurotoxin, has been shown to be elevated in SCI and can result in post-SCI neurological deficits. Reducing acrolein has therefore emerged as a novel and effective therapeutic strategy in SCI. Previous studies have revealed that hydralazine, an FDA approved blood pressure lowering medication, when administered after SCI shows strong acrolein scavenging capabilities and significantly improves cellular and behavioral outcomes. However, while effective at scavenging acrolein, hydralazine's blood pressure lowering activity can have a detrimental impact on neurotrauma patients. Here, our goal was to preserve the acrolein scavenging capability while mitigating the effect of hydralazine on blood pressure. We accomplished this using a folate-targeted delivery system to deploy hydralazine to the folate receptor positive inflammatory site of the cord injury. Using a model of rat SCI, we found that this system is effective for targeting the injury site, and that folate targeted hydralazine can scavenge acrolein without significantly impacting blood pressure.
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Affiliation(s)
- Seth A Herr
- Center for Paralysis Research & Department of Basic Medical Sciences, College of Veterinary Medicine, Purdue University. Lynn Hall, 625 N Harrison St. West Lafayette, IN, 47907, USA.
| | - Spencer S Gardeen
- Department of Chemistry, College of Science, Purdue University. Drug Discovery Building, 720 Clinic Dr. West Lafayette, IN, 47907, USA.
| | - Philip S Low
- Department of Chemistry, College of Science, Purdue University. Drug Discovery Building, 720 Clinic Dr. West Lafayette, IN, 47907, USA.
| | - Riyi Shi
- Center for Paralysis Research & Department of Basic Medical Sciences, College of Veterinary Medicine, Purdue University. Lynn Hall, 625 N Harrison St. West Lafayette, IN, 47907, USA.
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25
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Wu Q, Wang H, Liu X, Zhao Y, Zhang J. The Role of the Negative Regulation of Microglia-Mediated Neuroinflammation in Improving Emotional Behavior After Epileptic Seizures. Front Neurol 2022; 13:823908. [PMID: 35493845 PMCID: PMC9046666 DOI: 10.3389/fneur.2022.823908] [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: 12/24/2021] [Accepted: 03/16/2022] [Indexed: 11/13/2022] Open
Abstract
ObjectiveStudies have long shown that uncontrolled inflammatory responses in the brain play a key role in epilepsy pathogenesis. Microglias play an important role in epileptic-induced neuroinflammation, but their role after epileptic seizures is still poorly understood. Alleviating epilepsy and its comorbidities has become a key area of interest for pediatricians.MethodsA pilocarpine-induced rat model of epilepsy was established. The rats were randomly divided into four groups: a control group, epilepsy group, TLR4 inhibitor group (epilepsy+TAK-242), and NF-κB antagonist group (epilepsy+BAY11–7082).Results1. The results of TUNEL staining showed that the expression in rats in the epilepsy group was the most obvious and was significantly different from that in rats in the control, EP+BAY and EP+TAK groups. 2. The expression of TLR4 and NF-κB was highest in rats in the epilepsy group and was significantly different from that in rats in the control, EP+BAY and EP+TAK groups. 3. The fluorescence intensity and number of IBA-1-positive cells in rats in the epilepsy group were highest and significantly different from those in rats in the control, EP+BAY and EP+TAK groups. Western blot analysis of IBA-1 showed that the expression in rats in the epilepsy group was the highest and was statistically significant. 4. CD68 was the highest in rats in the epilepsy group and was statistically significant. 5. In the open-field experiment, the central region residence time of rats in the EP group was delayed, the central region movement distance traveled was prolonged, the total distance traveled was prolonged, and the average speed was increased. Compared with rats in the EP group, rats in the EP+BAY and EP+ TAK groups exhibited improvements to different degrees.ConclusionAt the tissue level, downregulation of the TLR4/NF-κB inflammatory pathway in epilepsy could inhibit microglial activation and the expression of the inflammatory factor CD68, could inhibit hyperphagocytosis, and inhibit the occurrence and exacerbation of epilepsy, thus improving cognitive and emotional disorders after epileptic seizures.
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García-Martínez M, Cortez LM, Otero A, Betancor M, Serrano-Pérez B, Bolea R, Badiola JJ, Garza MC. Distinctive Toll-like Receptors Gene Expression and Glial Response in Different Brain Regions of Natural Scrapie. Int J Mol Sci 2022; 23:ijms23073579. [PMID: 35408945 PMCID: PMC8998348 DOI: 10.3390/ijms23073579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Revised: 03/22/2022] [Accepted: 03/23/2022] [Indexed: 11/16/2022] Open
Abstract
Prion diseases are chronic and fatal neurodegenerative diseases characterized by the accumulation of disease-specific prion protein (PrPSc), spongiform changes, neuronal loss, and gliosis. Growing evidence shows that the neuroinflammatory response is a key component of prion diseases and contributes to neurodegeneration. Toll-like receptors (TLRs) have been proposed as important mediators of innate immune responses triggered in the central nervous system in other human neurodegenerative diseases, including Alzheimer’s disease, Parkinson’s disease, and amyotrophic lateral sclerosis. However, little is known about the role of TLRs in prion diseases, and their involvement in the neuropathology of natural scrapie has not been studied. We assessed the gene expression of ovine TLRs in four anatomically distinct brain regions in natural scrapie-infected sheep and evaluated the possible correlations between gene expression and the pathological hallmarks of prion disease. We observed significant changes in TLR expression in scrapie-infected sheep that correlate with the degree of spongiosis, PrPSc deposition, and gliosis in each of the regions studied. Remarkably, TLR4 was the only gene upregulated in all regions, regardless of the severity of neuropathology. In the hippocampus, we observed milder neuropathology associated with a distinct TLR gene expression profile and the presence of a peculiar microglial morphology, called rod microglia, described here for the first time in the brain of scrapie-infected sheep. The concurrence of these features suggests partial neuroprotection of the hippocampus. Finally, a comparison of the findings in naturallyinfected sheep versus an ovinized mouse model (tg338 mice) revealed distinct patterns of TLRgene expression.
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Affiliation(s)
- Mirta García-Martínez
- Centro de Encefalopatías y Enfermedades Transmisibles Emergentes, IA2, IIS Aragón, Universidad de Zaragoza, 50013 Zaragoza, Spain; (M.G.-M.); (M.B.); (R.B.); (J.J.B.)
| | - Leonardo M. Cortez
- Department of Medicine and Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, AB T6G 2G3, Canada
- Correspondence: (L.M.C.); (A.O.)
| | - Alicia Otero
- Centro de Encefalopatías y Enfermedades Transmisibles Emergentes, IA2, IIS Aragón, Universidad de Zaragoza, 50013 Zaragoza, Spain; (M.G.-M.); (M.B.); (R.B.); (J.J.B.)
- Correspondence: (L.M.C.); (A.O.)
| | - Marina Betancor
- Centro de Encefalopatías y Enfermedades Transmisibles Emergentes, IA2, IIS Aragón, Universidad de Zaragoza, 50013 Zaragoza, Spain; (M.G.-M.); (M.B.); (R.B.); (J.J.B.)
| | - Beatriz Serrano-Pérez
- Agrotecnio-CERCA Center, Department of Animal Science, University of Lleida, 25198 Lleida, Spain;
| | - Rosa Bolea
- Centro de Encefalopatías y Enfermedades Transmisibles Emergentes, IA2, IIS Aragón, Universidad de Zaragoza, 50013 Zaragoza, Spain; (M.G.-M.); (M.B.); (R.B.); (J.J.B.)
| | - Juan J. Badiola
- Centro de Encefalopatías y Enfermedades Transmisibles Emergentes, IA2, IIS Aragón, Universidad de Zaragoza, 50013 Zaragoza, Spain; (M.G.-M.); (M.B.); (R.B.); (J.J.B.)
| | - María Carmen Garza
- Departamento de Anatomía e Histología Humanas, IIS Aragón, Universidad de Zaragoza, 50009 Zaragoza, Spain;
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Eo H, Lee S, Kim SH, Ju IG, Huh E, Lim J, Park S, Oh MS. Petasites japonicus leaf extract inhibits Alzheimer's-like pathology through suppression of neuroinflammation. Food Funct 2022; 13:10811-10822. [DOI: 10.1039/d2fo01989b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Neuroinflammation is a crucial step involved in development and progression of Alzheimer's disease. The current study found that Petasites japonicus leaf extract inhibits neuroinflammation induced by lipopolysaccharides and amyloid beta oligomers.
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Affiliation(s)
- Hyeyoon Eo
- Department of Biomedical and Pharmaceutical Sciences, Graduate School, Kyung Hee University, Seoul 02447, Republic of Korea
| | - Seungmin Lee
- Department of Biomedical and Pharmaceutical Sciences, Graduate School, Kyung Hee University, Seoul 02447, Republic of Korea
| | - Seong Hye Kim
- Department of Biomedical and Pharmaceutical Sciences, Graduate School, Kyung Hee University, Seoul 02447, Republic of Korea
| | - In Gyoung Ju
- Department of Oriental Pharmaceutical Science and Kyung Hee East-West Pharmaceutical Research Institute, College of Pharmacy, Kyung Hee University, Seoul 02447, Republic of Korea
| | - Eugene Huh
- Department of Oriental Pharmaceutical Science and Kyung Hee East-West Pharmaceutical Research Institute, College of Pharmacy, Kyung Hee University, Seoul 02447, Republic of Korea
| | - Jeongin Lim
- NATUREBIO Co., Ltd., Seoul Biohub Industry-Academic Cooperation Center, Seoul 02447, Republic of Korea
| | - Sangsu Park
- NATUREBIO Co., Ltd., Seoul Biohub Industry-Academic Cooperation Center, Seoul 02447, Republic of Korea
| | - Myung Sook Oh
- Department of Biomedical and Pharmaceutical Sciences, Graduate School, Kyung Hee University, Seoul 02447, Republic of Korea
- Department of Oriental Pharmaceutical Science and Kyung Hee East-West Pharmaceutical Research Institute, College of Pharmacy, Kyung Hee University, Seoul 02447, Republic of Korea
- Department of Integrated Drug Development and Natural Products, Graduate School, Kyung Hee University, Seoul 02447, Republic of Korea
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Tsai CM, Chang SF, Li CC, Chang H. Transcranial photobiomodulation (808 nm) attenuates pentylenetetrazole-induced seizures by suppressing hippocampal neuroinflammation, astrogliosis, and microgliosis in peripubertal rats. NEUROPHOTONICS 2022; 9:015006. [PMID: 35345494 PMCID: PMC8955735 DOI: 10.1117/1.nph.9.1.015006] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2021] [Accepted: 01/19/2022] [Indexed: 06/14/2023]
Abstract
Significance: Transcranial photobiomodulation (tPBM) at 808 nm attenuates pentylenetetrazole (PTZ)-induced seizures and convulsive status epilepticus (CSE) in peripubertal rats by protecting neurons from injury and parvalbumin-positive interneurons from apoptosis, and preserving the integrity of perisomatic inhibitory networks. However, the effects of tPBM on neuroinflammation, astrogliosis, and microgliosis in epileptic rat brains are unknown. Thus, further study to unveil these aspects is needed for understanding the phenomena of tPBM on pediatric CSE prevention. Aim: To evaluate the effects of tPBM on neuroinflammation, astrogliosis, and microgliosis in peripubertal rat hippocampus with PTZ-induced seizures and SE. Approach: An 808-nm diode laser was applied transcranially to peripubertal rats prior to PTZ injection. Immunofluorescence staining of neuron-specific enolase (NSE) was used as a marker of neuroinflammation, glial fibrillary acid protein (GFAP) for astrogliosis, ionized calcium-binding adapter molecule 1 (Iba-1) for microgliosis, and mitochondrial cytochrome c oxidase subunit 1 (MT-CO1) for confirming the involvement of cytochrome c oxidase (CCO). Results: tPBM significantly reduced NSE immunoreactivity in CA3 in PTZ-treated rats, GFAP immunoreactivity in CA1, and Iba-1 immunoreactivity in CA3. Enhancement of hippocampal MT-CO1 reflected that tPBM acted in CCO-dependent manner. Conclusions: tPBM (808) attenuated PTZ-induced seizures and SE by suppressing neuroinflammation, astrogliosis, and microgliosis in peripubertal rats.
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Affiliation(s)
- Chung-Min Tsai
- Taipei Medical University, Graduate Institute of Medical Sciences, College of Medicine, Taipei, Taiwan
- MacKay Children’s Hospital, Department of Pediatrics, Taipei, Taiwan
| | - Shwu-Fen Chang
- Taipei Medical University, Graduate Institute of Medical Sciences, College of Medicine, Taipei, Taiwan
| | - Chih-Chuan Li
- Taipei Medical University Hospital, Department of Pediatrics, Taipei, Taiwan
| | - Hsi Chang
- Taipei Medical University Hospital, Department of Pediatrics, Taipei, Taiwan
- Taipei Medical University, College of Medicine, School of Medicine, Department of Pediatrics, Taipei, Taiwan
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29
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Bonilla-Jaime H, Zeleke H, Rojas A, Espinosa-Garcia C. Sleep Disruption Worsens Seizures: Neuroinflammation as a Potential Mechanistic Link. Int J Mol Sci 2021; 22:12531. [PMID: 34830412 PMCID: PMC8617844 DOI: 10.3390/ijms222212531] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2021] [Revised: 11/16/2021] [Accepted: 11/18/2021] [Indexed: 12/13/2022] Open
Abstract
Sleep disturbances, such as insomnia, obstructive sleep apnea, and daytime sleepiness, are common in people diagnosed with epilepsy. These disturbances can be attributed to nocturnal seizures, psychosocial factors, and/or the use of anti-epileptic drugs with sleep-modifying side effects. Epilepsy patients with poor sleep quality have intensified seizure frequency and disease progression compared to their well-rested counterparts. A better understanding of the complex relationship between sleep and epilepsy is needed, since approximately 20% of seizures and more than 90% of sudden unexpected deaths in epilepsy occur during sleep. Emerging studies suggest that neuroinflammation, (e.g., the CNS immune response characterized by the change in expression of inflammatory mediators and glial activation) may be a potential link between sleep deprivation and seizures. Here, we review the mechanisms by which sleep deprivation induces neuroinflammation and propose that neuroinflammation synergizes with seizure activity to worsen neurodegeneration in the epileptic brain. Additionally, we highlight the relevance of sleep interventions, often overlooked by physicians, to manage seizures, prevent epilepsy-related mortality, and improve quality of life.
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Affiliation(s)
- Herlinda Bonilla-Jaime
- Departamento de Biología de la Reproducción, Área de Biología Conductual y Reproductiva, Universidad Autónoma Metropolitana-Iztapalapa, Ciudad de Mexico CP 09340, Mexico;
| | - Helena Zeleke
- Neuroscience and Behavioral Biology Program, College of Arts and Sciences, Emory University, Atlanta, GA 30322, USA;
| | - Asheebo Rojas
- Department of Pharmacology and Chemical Biology, School of Medicine, Emory University, Atlanta, GA 30322, USA
| | - Claudia Espinosa-Garcia
- Department of Pharmacology and Chemical Biology, School of Medicine, Emory University, Atlanta, GA 30322, USA
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Peterson AR, Garcia TA, Ford BD, Binder DK. Regulation of NRG-1-ErbB4 signaling and neuroprotection by exogenous neuregulin-1 in a mouse model of epilepsy. Neurobiol Dis 2021; 161:105545. [PMID: 34742879 DOI: 10.1016/j.nbd.2021.105545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 10/28/2021] [Accepted: 11/02/2021] [Indexed: 11/27/2022] Open
Abstract
Temporal lobe epilepsy (TLE) is the most common form of focal epilepsy. Dysregulation of glutamate transporters has been a common finding across animal models of epilepsy and in patients with TLE. In this study, we investigate NRG-1/ErbB4 signaling in epileptogenesis and the neuroprotective effects of NRG-1 treatment in a mouse model of temporal lobe epilepsy. Using immunohistochemistry, we report the first evidence for NRG-1/ErbB4-dependent selective upregulation of glutamate transporter EAAC1 and bihemispheric neuroprotection by exogeneous NRG-1 in the intrahippocampal kainic acid (IHKA) model of TLE. Our findings provide evidence that dysregulation of glutamate transporter EAAC1 contributes to the development of epilepsy and can be therapeutically targeted to reduce neuronal death following IHKA-induced status epilepticus (SE).
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Affiliation(s)
- Allison R Peterson
- Division of Biomedical Sciences, School of Medicine, Center for Glial-Neuronal Interactions, University of California, Riverside, CA, USA
| | - Terese A Garcia
- Division of Biomedical Sciences, School of Medicine, Center for Glial-Neuronal Interactions, University of California, Riverside, CA, USA
| | - Byron D Ford
- Division of Biomedical Sciences, School of Medicine, Center for Glial-Neuronal Interactions, University of California, Riverside, CA, USA
| | - Devin K Binder
- Division of Biomedical Sciences, School of Medicine, Center for Glial-Neuronal Interactions, University of California, Riverside, CA, USA.
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Yamamoto H, Yamamura K, Nagasaki H, Suzuki T, Ninomiya F, Matsubara K, Harada N, Ohkubo S. Genome editing of Nf1, Pten, and Trp53 in neonatal mice induces glioblastomas positive for oligodendrocyte lineage transcription factor 2. J Toxicol Pathol 2021; 34:359-365. [PMID: 34629735 PMCID: PMC8484922 DOI: 10.1293/tox.2021-0029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Accepted: 07/05/2021] [Indexed: 12/21/2022] Open
Abstract
To generate a mouse glioblastoma model by genome editing, we introduced Cas9 protein and
guide RNAs specific for Nf1, Pten, and
Trp53 into the neonatal mouse forebrain by electroporation. We found a
high incidence (approximately 90%) of glial tumor development, including glioblastomas, 15
weeks later. The histological features of the tumors were similar to those of diffuse
gliomas and, in some cases, similar to human glioblastomas, with microvascular
proliferation (glomeruloid structure). In addition, unlike glial fibrillary acidic protein
(GFAP)-positive glioblastomas generated using a similar method in a previous model, the
majority of tumor cells were positive for oligodendrocyte lineage transcription factor 2,
but negative for GFAP and neurofilaments. One base pair insertions identical to those seen
in a previous model were found around the target sequences in Nf1,
Pten, and Trp53, and additional deletions were found
only in Pten. Considering that the histological characteristics were
different from those seen in the previous model, our new model provides an additional
research tool to investigate the early stages of glioblastoma development.
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Affiliation(s)
- Hiromi Yamamoto
- Discovery and Preclinical Research Division, Taiho Pharmaceutical Co., Ltd., 3 Okubo, Tsukuba, Ibaraki 300-2611, Japan
| | - Keisuke Yamamura
- Discovery and Preclinical Research Division, Taiho Pharmaceutical Co., Ltd., 3 Okubo, Tsukuba, Ibaraki 300-2611, Japan
| | - Haruka Nagasaki
- Discovery and Preclinical Research Division, Taiho Pharmaceutical Co., Ltd., 3 Okubo, Tsukuba, Ibaraki 300-2611, Japan
| | - Takamasa Suzuki
- Discovery and Preclinical Research Division, Taiho Pharmaceutical Co., Ltd., 3 Okubo, Tsukuba, Ibaraki 300-2611, Japan
| | - Fumiko Ninomiya
- Discovery and Preclinical Research Division, Taiho Pharmaceutical Co., Ltd., 3 Okubo, Tsukuba, Ibaraki 300-2611, Japan
| | - Kenji Matsubara
- Discovery and Preclinical Research Division, Taiho Pharmaceutical Co., Ltd., 3 Okubo, Tsukuba, Ibaraki 300-2611, Japan
| | - Naomoto Harada
- Discovery and Preclinical Research Division, Taiho Pharmaceutical Co., Ltd., 3 Okubo, Tsukuba, Ibaraki 300-2611, Japan
| | - Shuichi Ohkubo
- Discovery and Preclinical Research Division, Taiho Pharmaceutical Co., Ltd., 3 Okubo, Tsukuba, Ibaraki 300-2611, Japan
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Leite JP, Peixoto-Santos JE. Glia and extracellular matrix molecules: What are their importance for the electrographic and MRI changes in the epileptogenic zone? Epilepsy Behav 2021; 121:106542. [PMID: 31884121 DOI: 10.1016/j.yebeh.2019.106542] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Revised: 09/02/2019] [Accepted: 09/04/2019] [Indexed: 12/22/2022]
Abstract
Glial cells and extracellular matrix (ECM) molecules are crucial for the maintenance of brain homeostasis. Especially because of their actions regarding neurotransmitter and ionic control, and synaptic function, these cells can potentially contribute to the hyperexcitability seen in the epileptogenic, while ECM changes are linked to synaptic reorganization. The present review will explore glial and ECM homeostatic roles and their potential contribution to tissue plasticity. Finally, we will address how glial, and ECM changes in the epileptogenic zone can be seen in magnetic resonance imaging (MRI), pointing out their importance as markers for the extension of the epileptogenic area. This article is part of the Special Issue "NEWroscience 2018".
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Affiliation(s)
- Joao Pereira Leite
- Neurosciences and Behavioral Sciences, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto, Brazil.
| | - Jose Eduardo Peixoto-Santos
- Neurosciences and Behavioral Sciences, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto, Brazil; Department of Neurology and Neurosurgery, Paulista School of Medicine, UNIFESP, Sao Paulo, Brazil
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Wyatt-Johnson SK, Sommer AL, Shim KY, Brewster AL. Suppression of Microgliosis With the Colony-Stimulating Factor 1 Receptor Inhibitor PLX3397 Does Not Attenuate Memory Defects During Epileptogenesis in the Rat. Front Neurol 2021; 12:651096. [PMID: 34149593 PMCID: PMC8209304 DOI: 10.3389/fneur.2021.651096] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Accepted: 05/11/2021] [Indexed: 12/03/2022] Open
Abstract
Events of status epilepticus (SE) trigger the development of temporal lobe epilepsy (TLE), a type of focal epilepsy that is commonly drug-resistant and is highly comorbid with cognitive deficits. While SE-induced hippocampal injury, accompanied by gliosis and neuronal loss, typically disrupts cognitive functions resulting in memory defects, it is not definitively known how. Our previous studies revealed extensive hippocampal microgliosis that peaked between 2 and 3 weeks after SE and paralleled the development of cognitive impairments, suggesting a role for reactive microglia in this pathophysiology. Microglial survival and proliferation are regulated by the colony-stimulating factor 1 receptor (CSF1R). The CSF1R inhibitor PLX3397 has been shown to reduce/deplete microglial populations and improve cognitive performance in models of neurodegenerative disorders. Therefore, we hypothesized that suppression of microgliosis with PLX3397 during epileptogenesis may attenuate the hippocampal-dependent spatial learning and memory deficits in the rat pilocarpine model of SE and acquired TLE. Different groups of control and SE rats were fed standard chow (SC) or chow with PLX3397 starting immediately after SE and for 3 weeks. Novel object recognition (NOR) and Barnes maze (BM) were performed to determine memory function between 2 and 3 weeks after SE. Then microglial populations were assessed using immunohistochemistry. Control rats fed with either SC or PLX3397 performed similarly in both NOR and BM tests, differentiating novel vs. familiar objects in NOR, and rapidly learning the location of the hidden platform in BM. In contrast, both SE groups (SC and PLX3397) showed significant deficits in both NOR and BM tests compared to controls. Both PLX3397-treated control and SE groups had significantly decreased numbers of microglia in the hippocampus (60%) compared to those in SC. In parallel, we found that PLX3397 treatment also reduced SE-induced hippocampal astrogliosis. Thus, despite drastic reductions in microglial cells, memory was unaffected in the PLX3397-treated groups compared to those in SC, suggesting that remaining microglia may be sufficient to help maintain hippocampal functions. In sum, PLX3397 did not improve or worsen the memory deficits in rats that sustained pilocarpine-induced SE. Further research is required to determine whether microglia play a role in cognitive decline during epileptogenesis.
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Affiliation(s)
- Season K Wyatt-Johnson
- Department of Psychological Sciences, Purdue University, West Lafayette, IN, United States
| | - Alexandra L Sommer
- Department of Psychological Sciences, Purdue University, West Lafayette, IN, United States
| | - Kevin Y Shim
- Department of Psychological Sciences, Purdue University, West Lafayette, IN, United States
| | - Amy L Brewster
- Department of Psychological Sciences, Purdue University, West Lafayette, IN, United States.,Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, United States
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Zheng Z, Liang P, Hou B, Lu X, Ma Q, Yu X, Han S, Peng B, Chen T, Liu W, Yin J, He X. The effect of dipeptidyl peptidase IV on disease-associated microglia phenotypic transformation in epilepsy. J Neuroinflammation 2021; 18:112. [PMID: 33975617 PMCID: PMC8114532 DOI: 10.1186/s12974-021-02133-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Accepted: 03/18/2021] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Accumulating evidence suggests that disease-associated microglia (DAM), a recently discovered subset of microglia, plays a protective role in neurological diseases. Targeting DAM phenotypic transformation may provide new therapeutic options. However, the relationship between DAM and epilepsy remains unknown. METHODS Analysis of public RNA-sequencing data revealed predisposing factors (such as dipeptidyl peptidase IV; DPP4) for epilepsy related to DAM conversion. Anti-epileptic effect was assessed by electroencephalogram recordings and immunohistochemistry in a kainic acid (KA)-induced mouse model of epilepsy. The phenotype, morphology and function of microglia were assessed by qPCR, western blotting and microscopic imaging. RESULTS Our results demonstrated that DPP4 participated in DAM conversion and epilepsy. The treatment of sitagliptin (a DPP4 inhibitor) attenuated KA-induced epilepsy and promoted the expression of DAM markers (Itgax and Axl) in both mouse epilepsy model in vivo and microglial inflammatory model in vitro. With sitagliptin treatment, microglial cells did not display an inflammatory activation state (enlarged cell bodies). Furthermore, these microglia exhibited complicated intersections, longer processes and wider coverage of parenchyma. In addition, sitagliptin reduced the activation of NF-κB signaling pathway and inhibited the expression of iNOS, IL-1β, IL-6 and the proinflammatory DAM subset gene CD44. CONCLUSION The present results highlight that the DPP4 inhibitor sitagliptin can attenuate epilepsy and promote DAM phenotypic transformation. These DAM exhibit unique morphological features, greater migration ability and better surveillance capability. The possible underlying mechanism is that sitagliptin can reduce the activation of NF-κB signaling pathway and suppress the inflammatory response mediated by microglia. Thus, we propose DPP4 may act as an attractive direction for DAM research and a potential therapeutic target for epilepsy.
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Affiliation(s)
- Zhicheng Zheng
- Department of Pathophysiology, School of Basic Medical Sciences, Wuhan University, Donghu Road No. 185, Wuchang, Wuhan, 430071, China
| | - Peiyu Liang
- Department of Pathophysiology, School of Basic Medical Sciences, Wuhan University, Donghu Road No. 185, Wuchang, Wuhan, 430071, China
| | - Baohua Hou
- Medical College, Henan Polytechnic University, Jiaozuo, China
| | - Xin Lu
- Department of Pathophysiology, School of Basic Medical Sciences, Wuhan University, Donghu Road No. 185, Wuchang, Wuhan, 430071, China
| | - Qianwen Ma
- Department of Pathophysiology, School of Basic Medical Sciences, Wuhan University, Donghu Road No. 185, Wuchang, Wuhan, 430071, China
| | - Xiaomin Yu
- Department of Pathophysiology, School of Basic Medical Sciences, Wuhan University, Donghu Road No. 185, Wuchang, Wuhan, 430071, China
| | - Song Han
- Department of Pathophysiology, School of Basic Medical Sciences, Wuhan University, Donghu Road No. 185, Wuchang, Wuhan, 430071, China
| | - Biwen Peng
- Hubei Provincial Key Laboratory of Developmentally Originated Disease, School of Basic Medical Sciences, Wuhan University, Wuhan, China
| | - Taoxiang Chen
- Hubei Provincial Key Laboratory of Developmentally Originated Disease, School of Basic Medical Sciences, Wuhan University, Wuhan, China
| | - Wanhong Liu
- Hubei Province Key Laboratory of Allergy and Immunology, School of Basic Medical Sciences, Wuhan University, Wuhan, China
| | - Jun Yin
- Department of Pathophysiology, School of Basic Medical Sciences, Wuhan University, Donghu Road No. 185, Wuchang, Wuhan, 430071, China.
| | - Xiaohua He
- Department of Pathophysiology, School of Basic Medical Sciences, Wuhan University, Donghu Road No. 185, Wuchang, Wuhan, 430071, China.
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35
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Wu Z, Deshpande T, Henning L, Bedner P, Seifert G, Steinhäuser C. Cell death of hippocampal CA1 astrocytes during early epileptogenesis. Epilepsia 2021; 62:1569-1583. [PMID: 33955001 DOI: 10.1111/epi.16910] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 04/06/2021] [Accepted: 04/06/2021] [Indexed: 12/15/2022]
Abstract
OBJECTIVE Growing evidence suggests that dysfunctional astrocytes are crucial players in the development of mesial temporal lobe epilepsy (MTLE). Using a mouse model closely recapitulating key alterations of chronic human MTLE with hippocampal sclerosis, here we asked whether death of astrocytes contributes to the initiation of the disease and investigated potential underlying molecular mechanisms. METHODS Antibody staining was combined with confocal imaging and semiquantitative real-time polymerase chain reaction analysis to identify markers of different cellular death mechanisms between 4 h and 3 days after epilepsy induction. RESULTS Four hours after kainate-mediated induction of status epilepticus (SE), we found a significant reduction in the density of astrocytes in the CA1 stratum radiatum (SR) of the ipsilateral hippocampus. This reduction was transient, as within the next 3 days, astrocyte cell numbers recovered to the initial values, which was accompanied by enhanced proliferation. Four hours after SE induction, a small proportion of astrocytes in the ipsilateral CA1 SR expressed autophagy-related genes and proteins, whereas we did not find astrocytes positive for cleaved caspase 3 or terminal deoxynucleotide transferase-mediated deoxyuridine triphosphate nick-end labeling, ruling out apoptosis-related astrocytic death. Importantly, at the same early time point post-SE, many astrocytes in the ipsilateral CA1 SR showed strong expression of genes encoding pro-necroptosis factors, including receptor-interacting protein kinase 3 (RIPK3) and mixed lineage kinase domain-like protein (MLKL). Phosphorylation of MLKL (pMLKL), formation of necrosome complexes composed of RIPK3 and pMLKL, and translocation of pMLKL to the nucleus and to the plasma membrane were often observed in astrocytes of the ipsilateral hippocampus 4 h post-SE. SIGNIFICANCE The present study revealed that astrocytes die shortly after induction of SE. Our expression data and immunohistochemistry suggest that necroptosis and autophagy contribute to astrocytic death. These findings help to better understand how dysfunctional and pathological remodeling of astrocytes contributes to the initiation of temporal lobe epilepsy.
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Affiliation(s)
- Zhou Wu
- Institute of Cellular Neurosciences, Medical Faculty, University of Bonn, Bonn, Germany
| | - Tushar Deshpande
- Institute of Cellular Neurosciences, Medical Faculty, University of Bonn, Bonn, Germany.,Institute of Physiological Chemistry and Pathobiochemistry, University of Münster, Münster, Germany
| | - Lukas Henning
- Institute of Cellular Neurosciences, Medical Faculty, University of Bonn, Bonn, Germany
| | - Peter Bedner
- Institute of Cellular Neurosciences, Medical Faculty, University of Bonn, Bonn, Germany
| | - Gerald Seifert
- Institute of Cellular Neurosciences, Medical Faculty, University of Bonn, Bonn, Germany
| | - Christian Steinhäuser
- Institute of Cellular Neurosciences, Medical Faculty, University of Bonn, Bonn, Germany
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36
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Deficiency of Microglial Autophagy Increases the Density of Oligodendrocytes and Susceptibility to Severe Forms of Seizures. eNeuro 2021; 8:ENEURO.0183-20.2021. [PMID: 33472865 PMCID: PMC7890520 DOI: 10.1523/eneuro.0183-20.2021] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 12/11/2020] [Accepted: 01/02/2021] [Indexed: 12/14/2022] Open
Abstract
Excessive activation of mTOR in microglia impairs CNS homeostasis and causes severe epilepsy. Autophagy constitutes an important part of mTOR signaling. The contribution of microglial autophagy to CNS homeostasis and epilepsy remains to be determined. Here, we report that ATG7KO mice deficient for autophagy in microglia display a marked increase of myelination markers, a higher density of mature oligodendrocytes (ODCs), and altered lengths of the nodes of Ranvier. Moreover, we found that deficiency of microglial autophagy (ATG7KO) leads to increased seizure susceptibility in three seizure models (pilocarpine, kainic acid, and amygdala kindling). We demonstrated that ATG7KO mice develop severe generalized seizures and display nearly 100% mortality to convulsions induced by pilocarpine and kainic acid. In the amygdala kindling model, we observed significant facilitation of contralateral propagation of seizures, a process underlying the development of generalized seizures. Taken together, our results reveal impaired microglial autophagy as a novel mechanism underlying altered homeostasis of ODCs and increased susceptibility to severe and fatal generalized seizures.
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Vila Verde D, de Curtis M, Librizzi L. Seizure-Induced Acute Glial Activation in the in vitro Isolated Guinea Pig Brain. Front Neurol 2021; 12:607603. [PMID: 33574794 PMCID: PMC7870799 DOI: 10.3389/fneur.2021.607603] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 01/04/2021] [Indexed: 12/02/2022] Open
Abstract
Introduction: It has been proposed that seizures induce IL-1β biosynthesis in astrocytes and increase blood brain barrier (BBB) permeability, even without the presence of blood borne inflammatory molecules and leukocytes. In the present study we investigate if seizures induce morphological changes typically observed in activated glial cells. Moreover, we will test if serum albumin extravasation into the brain parenchyma exacerbates neuronal hyperexcitability by inducing astrocytic and microglial activation. Methods: Epileptiform seizure-like events (SLEs) were induced in limbic regions by arterial perfusion of bicuculline methiodide (BMI; 50 μM) in the in vitro isolated guinea pig brain preparation. Field potentials were recorded in both the hippocampal CA1 region and the medial entorhinal cortex. BBB permeability changes were assessed by analyzing extravasation of arterially perfused fluorescein isothiocyanate (FITC)–albumin. Morphological changes in astrocytes and microglia were evaluated with tridimensional reconstruction and Sholl analysis in the ventral CA1 area of the hippocampus following application of BMI with or without co-perfusion of human serum albumin. Results: BMI-induced SLE promoted morphological changes of both astrocytes and microglia cells into an activated phenotype, confirmed by the quantification of the number and length of their processes. Human-recombinant albumin extravasation, due to SLE-induced BBB impairment, worsened both SLE duration and the activated glia phenotype. Discussion: Our study provides the first direct evidence that SLE activity per se is able to promote the activation of astro- and microglial cells, as observed by their changes in phenotype, in brain regions involved in seizure generation; we also hypothesize that gliosis, significantly intensified by h-recombinant albumin extravasation from the bloodstream to the brain parenchyma due to SLE-induced BBB disruption, is responsible for seizure activity reinforcement.
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Affiliation(s)
- Diogo Vila Verde
- Epilepsy Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano, Italy
| | - Marco de Curtis
- Epilepsy Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano, Italy
| | - Laura Librizzi
- Epilepsy Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano, Italy
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Beesley S, Sullenberger T, Ailani R, D'Orio C, Crockett MS, Kumar SS. d-Serine Intervention In The Medial Entorhinal Area Alters TLE-Related Pathology In CA1 Hippocampus Via The Temporoammonic Pathway. Neuroscience 2021; 453:168-186. [PMID: 33197499 PMCID: PMC7796904 DOI: 10.1016/j.neuroscience.2020.10.025] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 10/20/2020] [Accepted: 10/22/2020] [Indexed: 01/15/2023]
Abstract
Entrainment of the hippocampus by the medial entorhinal area (MEA) in Temporal Lobe Epilepsy (TLE), the most common type of drug-resistant epilepsy in adults, is believed to be mediated primarily through the perforant pathway (PP), which connects stellate cells in layer (L) II of the MEA with granule cells of the dentate gyrus (DG) to drive the hippocampal tri-synaptic circuit. Using immunohistochemistry, high-resolution confocal microscopy and the rat pilocarpine model of TLE, we show here that the lesser known temporoammonic pathway (TAP) plays a significant role in transferring MEA pathology to the CA1 region of the hippocampus independently of the PP. The pathology observed was region-specific and restricted primarily to the CA1c subfield of the hippocampus. As shown previously, daily intracranial infusion of d-serine (100 μm), an antagonist of GluN3-containing triheteromeric N-Methyl d-aspartate receptors (t-NMDARs), into the MEA prevented loss of LIII neurons and epileptogenesis. This intervention in the MEA led to the rescue of hippocampal CA1 neurons that would have otherwise perished in the epileptic animals, and down regulation of the expression of astrocytes and microglia thereby mitigating the effects of neuroinflammation. Interestingly, these changes were not observed to a similar extent in other regions of vulnerability like the hilus, DG or CA3, suggesting that the pathology manifest in CA1 is driven predominantly through the TAP. This work highlights TAP's role in the entrainment of the hippocampus and identifies specific areas for therapeutic intervention in dealing with TLE.
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Affiliation(s)
- Stephen Beesley
- Department of Biomedical Sciences, College of Medicine & Program in Neuroscience, Florida State University, 1115 W. Call Street, Tallahassee, FL 32306-4300, United States
| | - Thomas Sullenberger
- Department of Biomedical Sciences, College of Medicine & Program in Neuroscience, Florida State University, 1115 W. Call Street, Tallahassee, FL 32306-4300, United States
| | - Roshan Ailani
- Department of Biomedical Sciences, College of Medicine & Program in Neuroscience, Florida State University, 1115 W. Call Street, Tallahassee, FL 32306-4300, United States
| | - Cameron D'Orio
- Department of Biomedical Sciences, College of Medicine & Program in Neuroscience, Florida State University, 1115 W. Call Street, Tallahassee, FL 32306-4300, United States
| | - Mathew S Crockett
- Department of Biomedical Sciences, College of Medicine & Program in Neuroscience, Florida State University, 1115 W. Call Street, Tallahassee, FL 32306-4300, United States
| | - Sanjay S Kumar
- Department of Biomedical Sciences, College of Medicine & Program in Neuroscience, Florida State University, 1115 W. Call Street, Tallahassee, FL 32306-4300, United States.
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Nalamolu KR, Challa SR, Fornal CA, Grudzien NA, Jorgenson LC, Choudry MM, Smith NJ, Palmer CJ, Pinson DM, Klopfenstein JD, Veeravalli KK. Attenuation of the Induction of TLRs 2 and 4 Mitigates Inflammation and Promotes Neurological Recovery After Focal Cerebral Ischemia. Transl Stroke Res 2021; 12:923-936. [PMID: 33426628 DOI: 10.1007/s12975-020-00884-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 10/16/2020] [Accepted: 12/22/2020] [Indexed: 12/17/2022]
Abstract
The intense inflammatory response triggered in the brain after focal cerebral ischemia is detrimental. Recently, we showed that the suppression of toll-like receptors (TLRs) 2 and 4 attenuates infarct size and reduces the expression of pro-inflammatory cytokines in the ischemic brain. In this study, we further examined the effect of unsuppressed induction of TLRs 2 and 4 on the expression of its downstream signaling molecules and pro-inflammatory cytokines 1 week after reperfusion. The primary purpose of this study was to investigate the effect of simultaneous knockdown of TLRs 2 and 4 on M1/M2 microglial polarization dynamics and post-stroke neurological deficits and the recovery. Transient focal cerebral ischemia was induced in young adult male Sprague-Dawley rats by the middle cerebral artery occlusion (MCAO) procedure using a monofilament suture. Appropriate cohorts of rats were treated with a nanoparticle formulation of TLR2shRNA and TLR4shRNA (T2sh+T4sh) expressing plasmids (1 mg/kg each of T2sh and T4sh) or scrambled sequence inserted vector (vehicle control) expressing plasmids (2 mg/kg) intravenously via tail vein immediately after reperfusion. Animals from various cohorts were euthanized during reperfusion, and the ischemic brain tissue was isolated and utilized for PCR followed by agarose gel electrophoresis, real-time PCR, immunoblot, and immunofluorescence analysis. Appropriate groups were subjected to a battery of standard neurological tests at regular intervals until 14 days after reperfusion. The increased expression of both TLRs 2 and 4 and their downstream signaling molecules including the pro-inflammatory cytokines was observed even at 1-week after reperfusion. T2sh+T4sh treatment immediately after reperfusion attenuated the post-ischemic inflammation, preserved the motor function, and promoted recovery of the sensory and motor functions. We conclude that the post-ischemic induction of TLRs 2 and 4 persists for at least 7 days after reperfusion, contributes to the severity of acute inflammation, and impedes neurological recovery. Unlike previous studies in TLRs 2 or 4 knockout models, results of this study in a pharmacologically relevant preclinical rodent stroke model have translational significance.
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Affiliation(s)
- Koteswara Rao Nalamolu
- Department of Cancer Biology and Pharmacology, University of Illinois College of Medicine at Peoria, 1 Illini Dr, Peoria, IL, 61605, USA
- Department of Pharmaceutical and Biomedical Sciences, California Health Sciences University, Clovis, CA, USA
| | - Siva Reddy Challa
- Department of Cancer Biology and Pharmacology, University of Illinois College of Medicine at Peoria, 1 Illini Dr, Peoria, IL, 61605, USA
| | - Casimir A Fornal
- Department of Cancer Biology and Pharmacology, University of Illinois College of Medicine at Peoria, 1 Illini Dr, Peoria, IL, 61605, USA
| | - Natalia A Grudzien
- Department of Cancer Biology and Pharmacology, University of Illinois College of Medicine at Peoria, 1 Illini Dr, Peoria, IL, 61605, USA
| | - Laura C Jorgenson
- Department of Cancer Biology and Pharmacology, University of Illinois College of Medicine at Peoria, 1 Illini Dr, Peoria, IL, 61605, USA
| | - Mouneeb M Choudry
- Department of Cancer Biology and Pharmacology, University of Illinois College of Medicine at Peoria, 1 Illini Dr, Peoria, IL, 61605, USA
| | - Nathan J Smith
- Department of Surgery, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Cassandra J Palmer
- Department of Cancer Biology and Pharmacology, University of Illinois College of Medicine at Peoria, 1 Illini Dr, Peoria, IL, 61605, USA
| | - David M Pinson
- Department of Health Sciences Education, University of Illinois College of Medicine at Peoria, Peoria, IL, USA
| | - Jeffrey D Klopfenstein
- Department of Cancer Biology and Pharmacology, University of Illinois College of Medicine at Peoria, 1 Illini Dr, Peoria, IL, 61605, USA
- Department of Neurosurgery, University of Illinois College of Medicine at Peoria, Peoria, IL, USA
| | - Krishna Kumar Veeravalli
- Department of Cancer Biology and Pharmacology, University of Illinois College of Medicine at Peoria, 1 Illini Dr, Peoria, IL, 61605, USA.
- Department of Neurosurgery, University of Illinois College of Medicine at Peoria, Peoria, IL, USA.
- Department of Neurology, University of Illinois College of Medicine at Peoria, Peoria, IL, USA.
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Uzunalli G, Herr S, Dieterly AM, Shi R, Lyle LT. Structural disruption of the blood-brain barrier in repetitive primary blast injury. Fluids Barriers CNS 2021; 18:2. [PMID: 33413513 PMCID: PMC7789532 DOI: 10.1186/s12987-020-00231-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Accepted: 11/07/2020] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND Blast-induced traumatic brain injury (bTBI) is a growing health concern due to the increased use of low-cost improvised explosive devices in modern warfare. Mild blast exposures are common amongst military personnel; however, these women and men typically do not have adequate recovery time from their injuries due to the transient nature of behavioral symptoms. bTBI has been linked to heterogeneous neuropathology, including brain edema, neuronal degeneration and cognitive abnormalities depending on the intensity of blast overpressure and frequency. Recent studies have reported heterogeneity in blood-brain barrier (BBB) permeability following blast injury. There still remains a limited understanding of the pathologic changes in the BBB following primary blast injuries. In this study, our goal was to elucidate the pathologic pattern of BBB damage through structural analysis following single and repetitive blast injury using a clinically relevant rat model of bTBI. METHODS A validated, open-ended shock tube model was used to deliver single or repetitive primary blast waves. The pathology of the BBB was assessed using immunofluorescence and immunohistochemistry assays. All data were analyzed using the one-way ANOVA test. RESULTS We have demonstrated that exposure to repetitive blast injury affects the desmin-positive and CD13-positive subpopulations of pericytes in the BBB. Changes in astrocytes and microglia were also detected. CONCLUSION This study provides analysis of the BBB components after repetitive blast injury. These results will be critical as preventative and therapeutic strategies are established for veterans recovering from blast-induced traumatic brain injury.
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Affiliation(s)
- Gozde Uzunalli
- Department of Comparative Pathobiology, Purdue University College of Veterinary Medicine, West Lafayette, IN, USA
| | - Seth Herr
- Department of Basic Medical Sciences, Purdue University College of Veterinary Medicine, West Lafayette, IN, USA
| | - Alexandra M Dieterly
- Department of Comparative Pathobiology, Purdue University College of Veterinary Medicine, West Lafayette, IN, USA
| | - Riyi Shi
- Department of Basic Medical Sciences, Purdue University College of Veterinary Medicine, West Lafayette, IN, USA
- Purdue University Weldon School of Biomedical Engineering, West Lafayette, IN, USA
| | - L Tiffany Lyle
- Department of Comparative Pathobiology, Purdue University College of Veterinary Medicine, West Lafayette, IN, USA.
- Center for Cancer Research, Purdue University, West Lafayette, IN, USA.
- Center for Comparative Translational Research, Purdue University, West Lafayette, IN, USA.
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Giordano KR, Denman CR, Dubisch PS, Akhter M, Lifshitz J. An update on the rod microglia variant in experimental and clinical brain injury and disease. Brain Commun 2021; 3:fcaa227. [PMID: 33501429 PMCID: PMC7811762 DOI: 10.1093/braincomms/fcaa227] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 11/12/2020] [Accepted: 11/17/2020] [Indexed: 12/15/2022] Open
Abstract
Contemporary microglia morphologies include ramified, activated and amoeboid, with the morphology of microglia considered highly coupled to the cellular function. Rod microglia are an additional activated microglia variant observed in the ageing, injured and diseased brain. Rod microglia were reported frequently in the early 1900s by neuropathologists in post-mortem cases of general paresis, Alzheimer's disease and encephalitis, and then remained largely ignored for almost 100 years. Recent reports have renewed interest in rod microglia, most notably after experimental traumatic brain injury. Rod microglia are formed by the narrowing of the soma and retraction of planar processes, which results in the appearance of an elongated, rod-shaped cell. Rod microglia are most commonly observed in the cortex, aligned perpendicular to the dural surface and adjacent to neuronal processes; in the hippocampus, they are aligned perpendicular to hippocampal layers. Furthermore, rod microglia form trains with one another, apical end to basal end. By replicating the process of sketching microscopic observation, rod microglia are re-defined by circumnutation around the long axis. In this update, we summarize the rod microglia variant in clinical and experimental literature and advocate for investigation into mechanisms of rod microglia origin and function.
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Affiliation(s)
- Katherine R Giordano
- BARROW Neurological Institute at Phoenix Children's Hospital, Phoenix, AZ, USA.,Department of Child Health, University of Arizona College of Medicine-Phoenix, Phoenix, AZ, USA
| | - Charlotte R Denman
- Department of Child Health, University of Arizona College of Medicine-Phoenix, Phoenix, AZ, USA.,Department of Biology and Biochemistry, University of Bath, Bath, UK
| | | | - Murtaza Akhter
- BARROW Neurological Institute at Phoenix Children's Hospital, Phoenix, AZ, USA.,Department of Child Health, University of Arizona College of Medicine-Phoenix, Phoenix, AZ, USA.,Department of Emergency Medicine, University of Arizona College of Medicine-Phoenix, Phoenix, AZ, USA.,Maricopa Integrated Healthcare System, Phoenix, AZ, USA
| | - Jonathan Lifshitz
- BARROW Neurological Institute at Phoenix Children's Hospital, Phoenix, AZ, USA.,Department of Child Health, University of Arizona College of Medicine-Phoenix, Phoenix, AZ, USA.,Phoenix VA Health Care System, Phoenix, AZ, USA
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Chen QL, Xia L, Zhong SP, Wang Q, Ding J, Wang X. Bioinformatic analysis identifies key transcriptome signatures in temporal lobe epilepsy. CNS Neurosci Ther 2020; 26:1266-1277. [PMID: 33225612 PMCID: PMC7702228 DOI: 10.1111/cns.13470] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 09/26/2020] [Accepted: 09/26/2020] [Indexed: 12/18/2022] Open
Abstract
Aims To identify transcriptome signatures underlying epileptogenesis in temporal lobe epilepsy (TLE). Methods Robust rank aggregation analysis was used to integrate multiple microarrays in rodent models of TLE and determine differentially expressed genes (DEGs) in acute, latent, and chronic stages. Functional annotation and protein‐protein interaction analysis were performed to explore the potential functions of the DEGs and identify hub genes with the highest intramodular connectivity. The association between hub genes and hippocampal sclerosis/seizure frequency was analyzed using publicly available RNA‐sequencing datasets from TLE patients. We subsequently established a pilocarpine‐induced status epilepticus (SE) model in rats and validated mRNA expression of hub genes by quantitative reverse transcription PCR (qRT‐PCR). Results The DEGs in the acute, latent, and chronic phases of TLE in animal models were prominently enriched in inflammatory response. Hub genes identified in the acute phase mainly participated in biological processes including inflammation, blood‐brain barrier damage, and cell adhesion. The hub genes in the latent phase were related to microglia/macrophage activation (Emr1 and Aif1) and phagocytosis (Cd68, Tyrobp, and Lyz). In the chronic phase, the hub genes were associated with activation of complements and microglia/macrophages. We further found that some hub genes identified in human TLE, such as Tlr2, Lgals3, and Stat3, were positively correlated with seizure frequency. Other hub genes, including Lgals3 and Serpine1, were associated with hippocampus sclerosis. qRT‐PCR analysis confirmed that the mRNA levels of hub genes in rat hippocampus were significantly up‐regulated after SE induction. Conclusions Our integrated analysis identified hub genes in different stages of epilepsy. The functional annotations suggest that the activation and phagocytic activities of microglia/macrophages may play critical roles in epileptogenesis of TLE.
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Affiliation(s)
- Qing-Lan Chen
- Department of Neurology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Lu Xia
- Department of Neurology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Shao-Ping Zhong
- Department of Neurology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Qiang Wang
- Department of Neurology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Jing Ding
- Department of Neurology, Zhongshan Hospital, Fudan University, Shanghai, China.,CAS Center for Excellence in Brain Science and Intelligence Technology, Shanghai, China
| | - Xin Wang
- Department of Neurology, Zhongshan Hospital, Fudan University, Shanghai, China.,Department of The State Key Laboratory of Medical Neurobiology, The Institutes of Brain Science and the Collaborative Innovation Center for Brain Science, Fudan University, Shanghai, China
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Carrillo GL, Ballard VA, Glausen T, Boone Z, Teamer J, Hinkson CL, Wohlfert EA, Blader IJ, Fox MA. Toxoplasma infection induces microglia-neuron contact and the loss of perisomatic inhibitory synapses. Glia 2020; 68:1968-1986. [PMID: 32157745 PMCID: PMC7423646 DOI: 10.1002/glia.23816] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 02/25/2020] [Accepted: 02/26/2020] [Indexed: 12/17/2022]
Abstract
Infection and inflammation within the brain induces changes in neuronal connectivity and function. The intracellular protozoan parasite, Toxoplasma gondii, is one pathogen that infects the brain and can cause encephalitis and seizures. Persistent infection by this parasite is also associated with behavioral alterations and an increased risk for developing psychiatric illness, including schizophrenia. Current evidence from studies in humans and mouse models suggest that both seizures and schizophrenia result from a loss or dysfunction of inhibitory synapses. In line with this, we recently reported that persistent T. gondii infection alters the distribution of glutamic acid decarboxylase 67 (GAD67), an enzyme that catalyzes GABA synthesis in inhibitory synapses. These changes could reflect a redistribution of presynaptic machinery in inhibitory neurons or a loss of inhibitory nerve terminals. To directly assess the latter possibility, we employed serial block face scanning electron microscopy (SBFSEM) and quantified inhibitory perisomatic synapses in neocortex and hippocampus following parasitic infection. Not only did persistent infection lead to a significant loss of perisomatic synapses, it induced the ensheathment of neuronal somata by myeloid-derived cells. Immunohistochemical, genetic, and ultrastructural analyses revealed that these myeloid-derived cells included activated microglia. Finally, ultrastructural analysis identified myeloid-derived cells enveloping perisomatic nerve terminals, suggesting they may actively displace or phagocytose synaptic elements. Thus, these results suggest that activated microglia contribute to perisomatic inhibitory synapse loss following parasitic infection and offer a novel mechanism as to how persistent T. gondii infection may contribute to both seizures and psychiatric illness.
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Affiliation(s)
- Gabriela L. Carrillo
- Center for Neurobiology Research, Fralin Biomedical Research Institute at Virginia Tech Carilion, 2 Riverside Circle, Roanoke, VA 24016
- Graduate Program in Translational Biology, Medicine, and Health, Virginia Tech, Blacksburg, VA 24061
| | - Valerie A. Ballard
- Center for Neurobiology Research, Fralin Biomedical Research Institute at Virginia Tech Carilion, 2 Riverside Circle, Roanoke, VA 24016
- Roanoke Valley Governor’s School, Roanoke VA 24015
| | - Taylor Glausen
- Department of Microbiology and Immunology, University at Buffalo, Buffalo NY 14260
| | - Zack Boone
- Center for Neurobiology Research, Fralin Biomedical Research Institute at Virginia Tech Carilion, 2 Riverside Circle, Roanoke, VA 24016
- School of Neuroscience, Virginia Tech, Blacksburg, VA 24061
| | - Joseph Teamer
- Center for Neurobiology Research, Fralin Biomedical Research Institute at Virginia Tech Carilion, 2 Riverside Circle, Roanoke, VA 24016
- FBRI neuroSURF Program, Roanoke, VA 24016
| | - Cyrus L. Hinkson
- Center for Neurobiology Research, Fralin Biomedical Research Institute at Virginia Tech Carilion, 2 Riverside Circle, Roanoke, VA 24016
- Virginia Tech Carilion School of Medicine, Roanoke, VA 24016
| | | | - Ira J. Blader
- Department of Microbiology and Immunology, University at Buffalo, Buffalo NY 14260
| | - Michael A. Fox
- Center for Neurobiology Research, Fralin Biomedical Research Institute at Virginia Tech Carilion, 2 Riverside Circle, Roanoke, VA 24016
- School of Neuroscience, Virginia Tech, Blacksburg, VA 24061
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA 24061
- Department of Pediatrics, Virginia Tech Carilion School of Medicine, Roanoke, VA 24016
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Victor TR, Tsirka SE. Microglial contributions to aberrant neurogenesis and pathophysiology of epilepsy. NEUROIMMUNOLOGY AND NEUROINFLAMMATION 2020; 7:234-247. [PMID: 33154976 PMCID: PMC7641338 DOI: 10.20517/2347-8659.2020.02] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Microglia are dynamic cells that constitute the brain's innate immune system. Recently, research has demonstrated microglial roles beyond immunity, which include homeostatic roles in the central nervous system. The function of microglia is an active area of study, with insights into changes in neurogenesis and synaptic pruning being discovered in both health and disease. In epilepsy, activated microglia contribute to several changes that occur during epileptogenesis. In this review, we focus on the effects of microglia on neurogenesis and synaptic pruning, and discuss the current state of anti-seizure drugs and how they affect microglia during these processes. Our understanding of the role of microglia post-seizure is still limited and may be pivotal in recognizing new therapeutic targets for seizure intervention.
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Affiliation(s)
- Tanya R Victor
- Department of Pharmacological Sciences, Stony Brook University, Stony Brook, NY 11794, USA
| | - Stella E Tsirka
- Department of Pharmacological Sciences, Stony Brook University, Stony Brook, NY 11794, USA
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Ohgomori T, Jinno S. Modulation of neuropathology and cognitive deficits by lipopolysaccharide preconditioning in a mouse pilocarpine model of status epilepticus. Neuropharmacology 2020; 176:108227. [PMID: 32634527 DOI: 10.1016/j.neuropharm.2020.108227] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 06/15/2020] [Accepted: 06/29/2020] [Indexed: 02/06/2023]
Abstract
Recent studies indicate that microglia may play a critical role in epileptogenesis during the early post-status epilepticus (SE) period. In this study, we aimed to elucidate the effects of preconditioning of microglia with lipopolysaccharide (LPS) on neuropathology and cognitive deficits in a mouse pilocarpine model of SE. Mice were treated with an intraperitoneal injection of LPS 24 h before SE induction. The open field test at 13 days after SE showed that LPS preconditioning suppressed SE-induced hyperactivity. The Y-maze test at 14 days after SE showed that LPS preconditioning ameliorated SE-induced working memory impairment. The extent of neuronal damage was decreased by LPS preconditioning in the hippocampus of mice euthanized at 15 days after SE. Gene profile analysis of hippocampal microglia at 15 days after SE showed that the expression level of interleukin-1β was increased by SE induction but decreased by LPS preconditioning. By contrast, SE induction increased the expression levels of phagocytosis-related genes, and LPS preconditioning further enhanced their expression. Interestingly, LPS preconditioning increased the numerical density of hippocampal microglia expressing the 5D4 keratan sulfate epitope, a population of cells known to be involved in phagocytosis. The voxel density of glutamatergic synapses was increased by SE induction but decreased by LPS preconditioning, while GABAergic synapses were not affected by these procedures. Our findings indicate that LPS preconditioning may in part alleviate SE-related abnormal synaptogenesis and cognitive deficits, and also suggest that modulation of microglial activation during the early post-SE period may be a novel strategy for epilepsy treatment.
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Affiliation(s)
- Tomohiro Ohgomori
- Department of Anatomy and Neuroscience, Graduate School of Medical Sciences, Kyushu University, Fukuoka, 812-8582, Japan; Department of Rehabilitation, Faculty of Rehabilitation, Osaka Kawasaki Rehabilitation University, Kaizuka, 597-0104, Japan
| | - Shozo Jinno
- Department of Anatomy and Neuroscience, Graduate School of Medical Sciences, Kyushu University, Fukuoka, 812-8582, Japan.
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Boni JL, Kahanovitch U, Nwaobi SE, Floyd CL, Olsen ML. DNA methylation: A mechanism for sustained alteration of KIR4.1 expression following central nervous system insult. Glia 2020; 68:1495-1512. [PMID: 32068308 PMCID: PMC8665281 DOI: 10.1002/glia.23797] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Revised: 01/29/2020] [Accepted: 01/31/2020] [Indexed: 12/22/2022]
Abstract
Kir4.1, a glial-specific inwardly rectifying potassium channel, is implicated in astrocytic maintenance of K+ homeostasis. Underscoring the role of Kir4.1 in central nervous system (CNS) functioning, genetic mutations in KCNJ10, the gene which encodes Kir4.1, causes seizures, ataxia and developmental disability in humans. Kir4.1 protein and mRNA loss are consistently observed in CNS injury and neurological diseases linked to hyperexcitability and neuronal dysfunction, leading to the notion that Kir4.1 represents an attractive therapeutic target. Despite this, little is understood regarding the mechanisms that underpin this downregulation. Previous work by our lab revealed that DNA hypomethylation of the Kcnj10 gene functions to regulate mRNA levels during astrocyte maturation whereas hypermethylation in vitro led to decreased promoter activity. In the present study, we utilized two vastly different injury models with known acute and chronic loss of Kir4.1 protein and mRNA to evaluate the methylation status of Kcnj10 as a candidate molecular mechanism for reduced transcription and subsequent protein loss. Examining whole hippocampal tissue and isolated astrocytes, in a lithium-pilocarpine model of epilepsy, we consistently identified hypermethylation of CpG island two, which resides in the large intronic region spanning the Kcnj10 gene. Strikingly similar results were observed using the second injury paradigm, a fifth cervical (C5) vertebral hemi-contusion model of spinal cord injury. Our previous work indicates the same gene region is significantly hypomethylated when transcription increases during astrocyte maturation. Our results suggest that DNA methylation can bidirectionally modulate Kcnj10 transcription and may represent a targetable molecular mechanism for the restoring astroglial Kir4.1 expression following CNS insult.
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Affiliation(s)
- Jessica L Boni
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama
- School of Neuroscience, Virginia Polytechnic and State University, Blacksburg, Virginia
| | - Uri Kahanovitch
- School of Neuroscience, Virginia Polytechnic and State University, Blacksburg, Virginia
| | - Sinifunanya E Nwaobi
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama
- Division of Pediatric Neurology, UCLA Mattel Children's Hospital, University of California Los Angeles, Los Angeles, California
| | - Candace L Floyd
- Department of Physical Medicine and Rehabilitation, University of Alabama at Birmingham, Birmingham, Alabama
- Department of Physical Medicine and Rehabilitation, University of Utah Health, Salt Lake City, Utah
| | - Michelle L Olsen
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama
- School of Neuroscience, Virginia Polytechnic and State University, Blacksburg, Virginia
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47
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de Aquino PEA, Rabelo Bezerra J, de Souza Nascimento T, Tavares J, Rosal Lustosa Í, Chaves Filho AJM, Mottin M, Macêdo Gaspar D, de Andrade GM, Tavares Neves KR, Biagini G, Silveira ER, de Barros Viana GS. A Proline Derivative-Enriched Fraction from Sideroxylon obtusifolium Protects the Hippocampus from Intracerebroventricular Pilocarpine-Induced Injury Associated with Status Epilepticus in Mice. Int J Mol Sci 2020; 21:E4188. [PMID: 32545390 PMCID: PMC7312019 DOI: 10.3390/ijms21114188] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Revised: 06/08/2020] [Accepted: 06/08/2020] [Indexed: 02/07/2023] Open
Abstract
The N-methyl-(2S,4R)-trans-4-hydroxy-l-proline-enriched fraction (NMP) from Sideroxylon obtusifolium was evaluated as a neuroprotective agent in the intracerebroventricular (icv) pilocarpine (Pilo) model. To this aim, male mice were subdivided into sham (SO, vehicle), Pilo (300 µg/1 µL icv, followed by the vehicle per os, po) and NMP-treated groups (Pilo 300 µg/1 µL icv, followed by 100 or 200 mg/kg po). The treatments started one day after the Pilo injection and continued for 15 days. The effects of NMP were assessed by characterizing the preservation of cognitive function in both the Y-maze and object recognition tests. The hippocampal cell viability was evaluated by Nissl staining. Additional markers of damage were studied-the glial fibrillary acidic protein (GFAP) and the ionized calcium-binding adaptor molecule 1 (Iba-1) expression using, respectively, immunofluorescence and western blot analyses. We also performed molecular docking experiments revealing that NMP binds to the γ-aminobutyric acid (GABA) transporter 1 (GAT1). GAT1 expression in the hippocampus was also characterized. Pilo induced cognitive deficits, cell damage, increased GFAP, Iba-1, and GAT1 expression in the hippocampus. These alterations were prevented, especially by the higher NMP dose. These data highlight NMP as a promising candidate for the protection of the hippocampus, as shown by the icv Pilo model.
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Affiliation(s)
- Pedro Everson Alexandre de Aquino
- Department of Physiology and Pharmacology, Federal University of Ceará, Fortaleza 60430-270, Brazil; (P.E.A.d.A.); (J.R.B.); (T.d.S.N.); (J.T.); (A.J.M.C.F.); (D.M.G.); (G.M.d.A.); (K.R.T.N.)
| | - Jéssica Rabelo Bezerra
- Department of Physiology and Pharmacology, Federal University of Ceará, Fortaleza 60430-270, Brazil; (P.E.A.d.A.); (J.R.B.); (T.d.S.N.); (J.T.); (A.J.M.C.F.); (D.M.G.); (G.M.d.A.); (K.R.T.N.)
| | - Tyciane de Souza Nascimento
- Department of Physiology and Pharmacology, Federal University of Ceará, Fortaleza 60430-270, Brazil; (P.E.A.d.A.); (J.R.B.); (T.d.S.N.); (J.T.); (A.J.M.C.F.); (D.M.G.); (G.M.d.A.); (K.R.T.N.)
| | - Juliete Tavares
- Department of Physiology and Pharmacology, Federal University of Ceará, Fortaleza 60430-270, Brazil; (P.E.A.d.A.); (J.R.B.); (T.d.S.N.); (J.T.); (A.J.M.C.F.); (D.M.G.); (G.M.d.A.); (K.R.T.N.)
| | - Ítalo Rosal Lustosa
- PhD Program in Clinical and Experimental Medicine, University of Modena and Reggio Emilia, 41121 Modena, Italy;
| | - Adriano José Maia Chaves Filho
- Department of Physiology and Pharmacology, Federal University of Ceará, Fortaleza 60430-270, Brazil; (P.E.A.d.A.); (J.R.B.); (T.d.S.N.); (J.T.); (A.J.M.C.F.); (D.M.G.); (G.M.d.A.); (K.R.T.N.)
| | - Melina Mottin
- Laboratory of Molecular Modeling and Drug Design, LabMol, Faculty of Pharmacy, Federal University of Goiás, Goiás 74605-050, Brazil;
| | - Danielle Macêdo Gaspar
- Department of Physiology and Pharmacology, Federal University of Ceará, Fortaleza 60430-270, Brazil; (P.E.A.d.A.); (J.R.B.); (T.d.S.N.); (J.T.); (A.J.M.C.F.); (D.M.G.); (G.M.d.A.); (K.R.T.N.)
| | - Geanne Matos de Andrade
- Department of Physiology and Pharmacology, Federal University of Ceará, Fortaleza 60430-270, Brazil; (P.E.A.d.A.); (J.R.B.); (T.d.S.N.); (J.T.); (A.J.M.C.F.); (D.M.G.); (G.M.d.A.); (K.R.T.N.)
| | - Kelly Rose Tavares Neves
- Department of Physiology and Pharmacology, Federal University of Ceará, Fortaleza 60430-270, Brazil; (P.E.A.d.A.); (J.R.B.); (T.d.S.N.); (J.T.); (A.J.M.C.F.); (D.M.G.); (G.M.d.A.); (K.R.T.N.)
| | - Giuseppe Biagini
- Laboratory of Experimental Epileptology, Department of Biomedical Metabolic and Neural Sciences, University of Modena and Reggio Emilia, 41121 Modena, Italy
- Center for Neuroscience and Neurotechnology, University of Modena and Reggio Emilia, 41121 Modena, Italy
| | - Edilberto Rocha Silveira
- Department of Organic and Inorganic Chemistry, Federal University of Ceará, Fortaleza 60455-970, Brazil;
| | - Glauce Socorro de Barros Viana
- Department of Physiology and Pharmacology, Federal University of Ceará, Fortaleza 60430-270, Brazil; (P.E.A.d.A.); (J.R.B.); (T.d.S.N.); (J.T.); (A.J.M.C.F.); (D.M.G.); (G.M.d.A.); (K.R.T.N.)
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48
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Sanz P, Garcia-Gimeno MA. Reactive Glia Inflammatory Signaling Pathways and Epilepsy. Int J Mol Sci 2020; 21:ijms21114096. [PMID: 32521797 PMCID: PMC7312833 DOI: 10.3390/ijms21114096] [Citation(s) in RCA: 75] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 06/04/2020] [Accepted: 06/06/2020] [Indexed: 02/06/2023] Open
Abstract
Neuroinflammation and epilepsy are interconnected. Brain inflammation promotes neuronal hyper-excitability and seizures, and dysregulation in the glia immune-inflammatory function is a common factor that predisposes or contributes to the generation of seizures. At the same time, acute seizures upregulate the production of pro-inflammatory cytokines in microglia and astrocytes, triggering a downstream cascade of inflammatory mediators. Therefore, epileptic seizures and inflammatory mediators form a vicious positive feedback loop, reinforcing each other. In this work, we have reviewed the main glial signaling pathways involved in neuroinflammation, how they are affected in epileptic conditions, and the therapeutic opportunities they offer to prevent these disorders.
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Affiliation(s)
- Pascual Sanz
- Instituto de Biomedicina de Valencia (CSIC) and Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Jaime Roig 11, 46010 Valencia, Spain
- Correspondence: ; Tel.: +34-963391779; Fax: +34-963690800
| | - Maria Adelaida Garcia-Gimeno
- Department of Biotechnology, Escuela Técnica Superior de Ingeniería Agronómica y del Medio Natural (ETSIAMN), Universitat Politècnica de València, 46022 Valencia, Spain;
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49
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Dexamethasone after early-life seizures attenuates increased susceptibility to seizures, seizure-induced microglia activation and neuronal injury later in life. Neurosci Lett 2020; 728:134953. [DOI: 10.1016/j.neulet.2020.134953] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 03/26/2020] [Accepted: 03/31/2020] [Indexed: 12/29/2022]
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50
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Tomita N, Nakamura T, Sunden Y, Miyata H, Morita T. Temporal analysis of histopathology and cytokine expression in the rat cerebral cortex after insulin-induced hypoglycemia. Neuropathology 2020; 40:240-250. [PMID: 32080930 DOI: 10.1111/neup.12643] [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: 10/30/2019] [Revised: 12/24/2019] [Accepted: 12/25/2019] [Indexed: 11/30/2022]
Abstract
Hypoglycemic coma causes neuronal death in the cerebral neocortex; however, its unclear pathogenesis prevents the establishment of preventive measures. Inflammation plays a pivotal role in neuronal damage in the hypoglycemic state; however, the dynamics of glial cell activation or cytokine expression remain unknown. Here, we aimed to elucidate the spatiotemporal morphological changes of microglia and time-course cytokine expression profiles in the rat cerebral cortex after hypoglycemic coma. We performed histopathological and immunohistochemical (Iba1, neuronal nuclei, glial fibrillary acidic protein) analyses in the cingulate cortex and four areas of the neocortex: hindlimb area (HL), parietal cortex area 1 (Par1), parietal cortex area 2 (Par2), and perirhinal cortex (PRh). We measured tumor necrosis factor alpha (TNFα) and interleukin-6 messenger RNA (mRNA) expression by real-time reverse transcriptase-polymerase chain reaction. Necrotic neurons appeared in the neocortex as early as 3 h after hypoglycemic coma, while they were absent in the cingulate cortex. Neuronal nuclei-immunopositive neurons in the HL, Par2, and PRh were significantly less abundant than in the control at day 1. In Iba1 immunostaining, large rod-shaped cells were detected at 3-6 h after hypoglycemia, and commonly observed in the HL, Par2, and PRh. After 6 h, rod-shaped cells were rarely observed; instead, there was a prominent infiltration of hypertrophic and ameboid-shaped cells until day 7. The mRNA expression of TNFα was significantly higher than the control at 3-6 h after hypoglycemia in the neocortex, while it was significantly higher only at 3 h in the cingulate cortex. Our results indicate that early and transient appearance of rod-shaped microglia and persisting high TNFα expression levels characterize inflammatory responses to hypoglycemic neuronal damage in the cerebral neocortex, which might contribute to neuronal necrosis in response to transient hypoglycemic coma.
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Affiliation(s)
- Nagi Tomita
- Laboratory of Veterinary Pathology, Tottori University, Tottori, Japan.,The United Graduate School of Veterinary Science, Yamaguchi University, Yamaguchi, Japan
| | - Tomoki Nakamura
- Laboratory of Veterinary Pathology, Tottori University, Tottori, Japan
| | - Yuji Sunden
- Laboratory of Veterinary Pathology, Tottori University, Tottori, Japan
| | - Hajime Miyata
- Department of Neuropathology, Research Institute for Brain and Blood Vessels, Akita Cerebrospinal and Cardiovascular Center, Akita, Japan
| | - Takehito Morita
- Laboratory of Veterinary Pathology, Tottori University, Tottori, Japan
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