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Shin EJ, Jeong JH, Chung CK, Kim DJ, Wie MB, Park ES, Chung YH, Nam Y, Tran TV, Lee SY, Kim HJ, Ong WY, Kim HC. Ceruloplasmin is an endogenous protectant against kainate neurotoxicity. Free Radic Biol Med 2015; 84:355-372. [PMID: 25843655 DOI: 10.1016/j.freeradbiomed.2015.03.031] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2015] [Revised: 03/10/2015] [Accepted: 03/14/2015] [Indexed: 01/08/2023]
Abstract
To determine the role of ceruloplasmin (Cp) in epileptic seizures, we used a kainate (KA) seizure animal model and examined hippocampal samples from epileptic patients. Treatment with KA resulted in a time-dependent decrease in Cp protein expression in the hippocampus of rats. Cp-positive cells were colocalized with neurons or reactive astrocytes in KA-treated rats and epileptic patient samples. KA-induced seizures, initial oxidative stress (i.e., hydroxyl radical formation, lipid peroxidation, protein oxidation, and synaptosomal reactive oxygen species), altered iron status (increasing Fe(2+) accumulation and L-ferritin-positive reactive microglial cells and decreasing H-ferritin-positive neurons), and impaired glutathione homeostasis and neurodegeneration (i.e., Fluoro-Nissl and Fluoro-Jade B staining analyses) were more pronounced in Cp antisense oligonucleotide (ASO)- than in Cp sense oligonucleotide-treated rats. Consistently, Cp ASO facilitated KA-induced lactate dehydrogenase (LDH) release, Fe(2+) accumulation, and glutathione loss in neuron-rich and mixed cultures. However, Cp ASO did not alter KA-induced LDH release or Fe(2+) accumulation in the astroglial culture, but did facilitate impairment in glutathione homeostasis in the same culture. Importantly, treatment with human Cp protein resulted in a significant attenuation against these neurotoxicities induced by Cp ASO. Our results suggest that Cp-mediated neuroprotection occurs via the inhibition of seizure-associated oxidative damage (including impairment in glutathione homeostasis), Fe(2+) accumulation, and alterations in ferritin immunoreactivity. Moreover, interactive modulation between neurons and glia was found to be important for Cp upregulation in the attenuation of epileptic damage in both animals and humans.
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Affiliation(s)
- Eun-Joo Shin
- Neuropsychopharmacology and Toxicology Program, College of Pharmacy, Kangwon National University, Chunchon 200-701, South Korea
| | - Ji Hoon Jeong
- Department of Pharmacology, College of Medicine, Chung-Ang University, Seoul 156-756, South Korea
| | - Chun Kee Chung
- Department of Neurosurgery, Seoul National University College of Medicine, Seoul National University Hospital, Seoul 110-799, South Korea
| | - Dae-Joong Kim
- Department of Anatomy and Cell Biology, Medical School, Kangwon National University, Chunchon 200-701, South Korea
| | - Myung-Bok Wie
- Department of Veterinary Medicine, Kangwon National University, Chunchon 200-701, South Korea
| | - Eon Sub Park
- Department of Pathology, College of Medicine, Chung-Ang University, Seoul 156-756, South Korea
| | - Yoon Hee Chung
- Department of Anatomy, College of Medicine, Chung-Ang University, Seoul 156-756, South Korea
| | - Yunsung Nam
- Neuropsychopharmacology and Toxicology Program, College of Pharmacy, Kangwon National University, Chunchon 200-701, South Korea
| | - The-Vinh Tran
- Neuropsychopharmacology and Toxicology Program, College of Pharmacy, Kangwon National University, Chunchon 200-701, South Korea
| | - Sung Youl Lee
- Neuropsychopharmacology and Toxicology Program, College of Pharmacy, Kangwon National University, Chunchon 200-701, South Korea
| | - Hwa-Jung Kim
- College of Pharmacy, Ewha Women׳s University, Seoul 120-750, South Korea
| | - Wei-Yi Ong
- Department of Anatomy, National University of Singapore, Singapore 119260, Singapore
| | - Hyoung-Chun Kim
- Neuropsychopharmacology and Toxicology Program, College of Pharmacy, Kangwon National University, Chunchon 200-701, South Korea.
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Gao K, Wang CR, Jiang F, Wong AYK, Su N, Jiang JH, Chai RC, Vatcher G, Teng J, Chen J, Jiang YW, Yu ACH. Traumatic scratch injury in astrocytes triggers calcium influx to activate the JNK/c-Jun/AP-1 pathway and switch on GFAP expression. Glia 2013; 61:2063-77. [PMID: 24123203 DOI: 10.1002/glia.22577] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2013] [Revised: 08/11/2013] [Accepted: 08/21/2013] [Indexed: 01/25/2023]
Abstract
Astrocyte activation is a hallmark of central nervous system injuries resulting in glial scar formation (astrogliosis). The activation of astrocytes involves metabolic and morphological changes with complex underlying mechanisms, which should be defined to provide targets for astrogliosis intervention. Astrogliosis is usually accompanied by an upregulation of glial fibrillary acidic protein (GFAP). Using an in vitro scratch injury model, we scratched primary cultures of cerebral cortical astrocytes and observed an influx of calcium in the form of waves spreading away from the wound through gap junctions. Using the calcium blocker BAPTA-AM and the JNK inhibitor SP600125, we demonstrated that the calcium wave triggered the activation of JNK, which then phosphorylated the transcription factor c-Jun to facilitate the binding of AP-1 to the GFAP gene promoter to switch on GFAP upregulation. Blocking calcium mobilization with BAPTA-AM in an in vivo stab wound model reduced GFAP expression and glial scar formation, showing that the calcium signal, and the subsequent regulation of downstream signaling molecules, plays an essential role in brain injury response. Our findings demonstrated that traumatic scratch injury to astrocytes triggered a calcium influx from the extracellular compartment and activated the JNK/c-Jun/AP-1 pathway to switch on GFAP expression, identifying a previously unreported signaling cascade that is important in astrogliosis and the physiological response following brain injury.
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Affiliation(s)
- Kai Gao
- Neuroscience Research Institute, Key Laboratory for Neuroscience (Ministry of Education), Key Laboratory for Neuroscience (National Health and Family Planning Commission), Department of Neurobiology, School of Basic Medical Sciences, Health Science Center, Peking University, Beijing, China
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