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Lietzau G, Sienkiewicz W, Karwacki Z, Dziewiątkowski J, Kaleczyc J, Kowiański P. The Effect of Simvastatin on the Dynamics of NF-κB-Regulated Neurodegenerative and Neuroprotective Processes in the Acute Phase of Ischemic Stroke. Mol Neurobiol 2023; 60:4935-4951. [PMID: 37204689 PMCID: PMC10415422 DOI: 10.1007/s12035-023-03371-2] [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: 02/02/2023] [Accepted: 04/27/2023] [Indexed: 05/20/2023]
Abstract
Statins are lipid-lowering drugs that act by inhibiting 3-hydroxy-3-methylglutaryl coenzyme A reductase, a rate-limiting enzyme in cholesterol biosynthesis. Animal studies have shown neuroprotective effects of statins in cerebral stroke. However, the underlying mechanisms are not fully understood. The nuclear factor-kappa B (NF-κB) transcription factor is involved in the regulation of apoptosis in stroke. Different dimers of NF-κB regulate the gene expression of proteins involved in both neurodegeneration and neuroprotection. We aimed to determine whether simvastatin improves stroke outcome via inhibition of the RelA/p65-containing subunit and downregulation of stroke-induced pro-apoptotic genes or via activation of NF-κB dimers containing the c-Rel subunit and upregulation of anti-apoptotic genes during the acute stroke phase. Eighteen-month-old Wistar rats, subjected to permanent MCAO or sham surgery, were administered simvastatin (20 mg/kg b.w.) or saline for 5 days before the procedure. Stroke outcome was determined by measuring cerebral infarct and assessing motor functions. The expression of NF-κB subunits in various cell populations was investigated using immunofluorescence/confocal microscopy. RelA and c-Rel were detected by WB. The NF-κB-DNA binding activity was investigated using EMSA, and expression of Noxa, Puma, Bcl-2, and Bcl-x genes was analyzed by qRT-PCR. Results showed a 50% infarct size reduction and significant motor function improvement in the simvastatin-treated animals which correlated with a decrease in RelA and a transient increase in the c-Rel level in the nucleus, normalization of the NF-κB-DNA binding activity, and downregulation of the NF-κB-regulated genes. Our results provide new insights into the statin-mediated neuroprotective action against stroke based on NF-κB pathway inhibition.
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Affiliation(s)
- Grazyna Lietzau
- Division of Anatomy and Neurobiology, Faculty of Medicine, Medical University of Gdańsk, Dębinki 1, 80-211 Gdańsk, Poland
| | - Waldemar Sienkiewicz
- Department of Animal Anatomy, Faculty of Veterinary Medicine, University of Warmia and Mazury, Oczapowskiego 13, 10-719 Olsztyn, Poland
| | - Zbigniew Karwacki
- Department of Neuroanaesthesiology, Faculty of Medicine, Medical University of Gdańsk, Dębinki 7, 80-211 Gdańsk, Poland
| | - Jerzy Dziewiątkowski
- Division of Anatomy and Neurobiology, Faculty of Medicine, Medical University of Gdańsk, Dębinki 1, 80-211 Gdańsk, Poland
| | - Jerzy Kaleczyc
- Department of Animal Anatomy, Faculty of Veterinary Medicine, University of Warmia and Mazury, Oczapowskiego 13, 10-719 Olsztyn, Poland
| | - Przemysław Kowiański
- Division of Anatomy and Neurobiology, Faculty of Medicine, Medical University of Gdańsk, Dębinki 1, 80-211 Gdańsk, Poland
- Institute of Health Sciences, Pomeranian University in Słupsk, Bohaterów Westerplatte 64, 76-200 Słupsk, Poland
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Hernandez VG, Lechtenberg KJ, Peterson TC, Zhu L, Lucas TA, Owah JO, Dorsey AI, Gentles AJ, Buckwalter MS. Translatome analysis reveals microglia and astrocytes to be distinct regulators of inflammation in the hyperacute and acute phases after stroke. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.14.520351. [PMID: 36824949 PMCID: PMC9949064 DOI: 10.1101/2023.02.14.520351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
Neuroinflammation is a hallmark of ischemic stroke, which is a leading cause of death and long-term disability. Understanding the exact cellular signaling pathways that initiate and propagate neuroinflammation after stroke will be critical for developing immunomodulatory stroke therapies. In particular, the precise mechanisms of inflammatory signaling in the clinically relevant hyperacute period, hours after stroke, have not been elucidated. We used the RiboTag technique to obtain astrocyte and microglia-derived mRNA transcripts in a hyperacute (4 hours) and acute (3 days) period after stroke, as these two cell types are key modulators of acute neuroinflammation. Microglia initiated a rapid response to stroke at 4 hours by adopting an inflammatory profile associated with the recruitment of immune cells. The hyperacute astrocyte profile was marked by stress response genes and transcription factors, such as Fos and Jun , involved in pro-inflammatory pathways such as TNF-α. By 3 days, microglia shift to a proliferative state and astrocytes strengthen their inflammatory response. The astrocyte pro-inflammatory response at 3 days is partially driven by the upregulation of the transcription factors C/EBPβ, Spi1 , and Rel , which comprise 25% of upregulated transcription factor-target interactions. Surprisingly, few sex differences across all groups were observed. Expression and log 2 fold data for all sequenced genes are available on a user-friendly website for researchers to examine gene changes and generate hypotheses for stroke targets. Taken together our data comprehensively describe the astrocyte and microglia-specific translatome response in the hyperacute and acute period after stroke and identify pathways critical for initiating neuroinflammation.
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Li Y, Lv X, Jiang M, Jin Z. Sitagliptin ameliorates hypoxia-induced damages in endometrial stromal cells: an implication in endometriosis. Bioengineered 2021; 13:800-809. [PMID: 34964708 PMCID: PMC8805946 DOI: 10.1080/21655979.2021.2012950] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Hypoxia-induced damage in endometrial stromal cells (ESCs) is an important event in the pathological progression of Endometriosis. It is reported that significant inflammation is induced by hypoxia in ESCs, mediated by serval inflammatory progressions, pathways, or factors. Sitagliptin, an important member of the dipeptidyl peptidase-4 (DPP-4) inhibitors family and has been widely used for the management of type 2 diabetes. It has been recently reported to exert significant anti-inflammatory effects. Here, we aim to assess whether Sitagliptin possesses a protective effect against hypoxia-induced damages in ESCs. Our findings indicate that exposure to hypoxia significantly increased oxidative stress in ESCs by increasing the production of reactive oxygen species (ROS) and decreasing the levels of reduced glutathione (GSH), which was ameliorated by Sitagliptin. Additionally, the excessively produced inflammatory mediators, including tumor necrosis factor (TNF)-α, interleukin (IL)-6, monocyte chemoattractant protein-1 (MCP-1), cyclooxygenase-2 (COX-2), prostaglandin E2 (PGE2), and high mobility group box (HMGB)-1, in hypoxia-treated HESCs were pronouncedly repressed by Sitagliptin. The activated p38 mitogen-activated protein kinases (MAPK) pathway was observed in hypoxia-stimulated HESCs, then greatly inhibited by the introduction of Sitagliptin. Lastly, hypoxia-induced phosphorylation and degradation of IκBα, as well as the upregulation of nuclear factor kappa-B (NF-κB) p65 and increased transcriptional activity of NF-κB, were dramatically abolished by Sitagliptin. Collectively, Sitagliptin ameliorated hypoxia-induced damages in ESCs by suppressing the inflammation.
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Affiliation(s)
- Ying Li
- Department of Outpatient, The First Affiliated Hospital of Jinzhou Medical University, Jinzhou City, Liaoning Province, China
| | - Xiaolin Lv
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Jinzhou Medical University, Jinzhou City, Liaoning Province, China
| | - Mei Jiang
- Department of Outpatient, The First Affiliated Hospital of Jinzhou Medical University, Jinzhou City, Liaoning Province, China
| | - Zhili Jin
- Department of Rheumatology, The First Affiliated Hospital of Jinzhou Medical University, Jinzhou City, Liaoning Province, China
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4
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Meng Q, Lu Q, Zhang Z, Liu J, Lou Y, Wang Y, Liu J. Nesfatin-1 inhibits free fatty acids (FFAs)-induced endothelial inflammation via Gfi1/NF-κB signaling. Biosci Biotechnol Biochem 2021; 86:47-55. [PMID: 34724039 DOI: 10.1093/bbb/zbab186] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Accepted: 10/02/2021] [Indexed: 11/14/2022]
Abstract
Nesfatin-1 is a neuropeptide produced in the hypothalamus. It is known that Nesfatin-1 is involved in food uptake, fat storage, and other metabolic regulation. We hypothesized that Nesfatin-1 may play a role in cardiovascular tissue. Free fatty acids (FFAs) are known to be the risk factor for cardiovascular diseases. FFAs mediated endothelial dysfunction is the critical mechanism of many cardiovascular disorders. The present study explores the protective effects of Nesfatin-1 on FFAs-induced endothelial inflammation and the underlying mechanism. We found that significantly increased lactate dehydrogenase (LDH) release and production of inflammatory factors were observed in FFAs treated human aortic endothelial cells (HAECs), accompanied by the enhanced attachment of U937 monocytes to HAECs and upregulated cell adhesion molecule vascular cell adhesion molecule-1 (VCAM-1), which were dramatically reversed by the treatment with Nesfatin-1. In addition, the promoted level of nuclear regulator NF-κB p65 and transcriptional function of NF-κB in FFAs treated HAECs were greatly suppressed by HAECs. Growth Factor Independent 1 Transcriptional Repressor 1 (Gfi1), an important negative regulator of NF-κB activity, was significantly downregulated in HAECs by FFAs and was upregulated by Nesfatin-1. Lastly, the inhibitory effects of Nesfatin-1 against FFAs-induced NF-κB activation and adhesion of U937 monocytes to HAECs were abolished by the knockdown of Gfi1. In conclusion, our data reveal that Nesfatin-1 inhibited FFAs-induced endothelial inflammation mediated by the Gfi1/NF-κB signaling pathway.
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Affiliation(s)
- Qingtao Meng
- Department of Cardiovascular Surgery, Affiliated Zhongshan Hospital of Dalian University, Dalian, Liaoning, 116001, China
| | - Qin Lu
- Department of Cardiology, the Second Affiliated Hospital of Dalian Medical University, Dalian, Liaoning, 116021, China
| | - Zhipeng Zhang
- Department of Cardiology, Affiliated Zhongshan Hospital of Dalian University, Dalian, Liaoning, 116001, China
| | - Jiyi Liu
- Department of Cardiology, Affiliated Zhongshan Hospital of Dalian University, Dalian, Liaoning, 116001, China
| | - Yu Lou
- Department of Cardiology, the Second Affiliated Hospital of Dalian Medical University, Dalian, Liaoning, 116021, China
| | - Yuwei Wang
- Department of Cardiovascular Surgery, Affiliated Zhongshan Hospital of Dalian University, Dalian, Liaoning, 116001, China
| | - Jihong Liu
- Department of Cardiovascular Surgery, Affiliated Zhongshan Hospital of Dalian University, Dalian, Liaoning, 116001, China
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Ma D, Zheng B, Du H, Han X, Zhang X, Zhang J, Gao Y, Sun S, Chu L. The Mechanism Underlying the Protective Effects of Tannic Acid Against Isoproterenol-Induced Myocardial Fibrosis in Mice. Front Pharmacol 2020; 11:716. [PMID: 32499705 PMCID: PMC7242737 DOI: 10.3389/fphar.2020.00716] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2019] [Accepted: 04/30/2020] [Indexed: 12/15/2022] Open
Abstract
Tannic acid (TA) belongs to a class of complex water-soluble polyphenolic derivatives that show anticarcinogenic, antiinflammatory, antioxidant, and scavenging activities. Here, we investigate the protective effects of TA against isoproterenol (ISO)-induced myocardial fibrosis (MF) in mice. Mice received TA and ISO dosing and were sacrificed 48 h later. The activities of creatine kinase (CK), creatine kinase-MB (CK-MB), lactate dehydrogenase (LDH), and mitochondria enzymes were measured. Cardiac histopathology was done using H&E, Sirius red, and Masson’s Trichrome staining. Immunohistochemical staining was applied to indicate changes in B-cell lymphoma-2 (Bcl-2), Bcl-2-associated X protein (Bax), and basic fibroblast growth factor (bFGF) protein expressions in cardiac tissue. RT-PCR was used to measure the expression of atrial and brain natriuretic peptides (ANP and BNP, respectively), c-fos, and c-jun. Western blotting was used to measure the expression of nuclear factor-κB (NF-κB) p65, phosphorylated NF-κB p65), toll-like receptor 4 (TLR4), p38, phosphorylated p38, Bax, Bcl-2, and caspase-3. Compared to the ISO group, the TA group had reduced levels of TLR4, p38, p-p38, NF-κB (p65), p-NF-κB (p-p65), caspase-3, Bax, and Bcl-2, as well as CK, CK-MB, and LDH. These results indicate that TA protects against ISO-induced MF, possibly through its ability to suppress the TLR4-mediated NF-κB signaling pathway.
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Affiliation(s)
- Donglai Ma
- School of Pharmacy, Hebei University of Chinese Medicine, Shijiazhuang, China.,Collaborative Innovation Center of Integrative Reproductive Disorders, Hebei University of Chinese Medicine, Shijiazhuang, China.,Hebei Key Laboratory of Integrative Medicine on Liver-Kidney Patterns Hebei University of Chinese Medicine, Shijiazhuang, China
| | - Bin Zheng
- School of Pharmacy, Hebei University of Chinese Medicine, Shijiazhuang, China
| | - Huiru Du
- Department of Pharmaceutical Engineering, Hebei Chemical and Pharmaceutical College, Shijiazhuang, China
| | - Xue Han
- School of Pharmacy, Hebei University of Chinese Medicine, Shijiazhuang, China
| | - Xuan Zhang
- School of Basic Medicine, Hebei University of Chinese Medicine, Shijiazhuang, China
| | - Jianping Zhang
- School of Basic Medicine, Hebei University of Chinese Medicine, Shijiazhuang, China
| | - Yonggang Gao
- School of Basic Medicine, Hebei University of Chinese Medicine, Shijiazhuang, China
| | - Shijiang Sun
- Hebei Province Hospital of Chinese Medicine, Affiliated Hospital, Hebei University of Chinese Medicine, Shijiazhuang, China
| | - Li Chu
- School of Pharmacy, Hebei University of Chinese Medicine, Shijiazhuang, China.,Hebei Key Laboratory of Integrative Medicine on Liver-Kidney Patterns Hebei University of Chinese Medicine, Shijiazhuang, China
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6
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Chen H, Lin W, Lin P, Zheng M, Lai Y, Chen M, Zhang Y, Chen J, Lin X, Lin L, Lan Q, Yuan Q, Chen R, Jiang X, Xiao Y, Liu N. IL-10 produces a dual effect on OGD-induced neuronal apoptosis of cultured cortical neurons via the NF-κB pathway. Aging (Albany NY) 2019; 11:10796-10813. [PMID: 31801113 PMCID: PMC6932931 DOI: 10.18632/aging.102411] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Accepted: 11/19/2019] [Indexed: 12/15/2022]
Abstract
As a classic immunoregulatory cytokine, interleukin-10 (IL-10) can provide in vivo and in vitro neuroprotection respectively during cerebral ischemia and after the oxygen-glucose deprivation (OGD)-induced injury. However, its role in cortical neuronal survival at different post-ischemic phases remains unclear. The current study found that IL-10 had distinct effects on the neuronal apoptosis at different OGD stages: at an early stage after OGD, IL-10 promoted the OGD-induced neuronal apoptosis in the cultured primary cortical neurons by activating p65 subunit, which up-regulated Bax expression and down-regulated Bcl-xL expression; at a late OGD stage, however, it attenuated the OGD-induced neuronal apoptosis by activating c-Rel, which up-regulated Bcl-xL expression and down-regulated Bax expression. The early-stage pro-apoptosis and late-stage anti-apoptosis were both partly abolished by PDTC, an NF-κB inhibitor, and promoted by PMA, an NF-κB activator. The optimal anti-apoptotic effect appeared when the cultured neurons were treated with IL-10 at 9-24 h after OGD. Taken together, our findings suggest that IL-10 exerts a dual effect on the survival of the cultured neurons by activating the NF-κB pathway at different stages after OGD injury and that PMA treatment at a late stage can facilitate the IL-10-conferred neuroprotection against OGD-induced neuronal injury.
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Affiliation(s)
- Hongbin Chen
- Department of Neurology, Fujian Medical University Union Hospital, Fuzhou, China.,Institute of Cerebral Vascular Diseases of Fujian Province, Fuzhou, China.,Key Laboratory of Brain Aging and Neurodegenerative Diseases, Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, China
| | - Wei Lin
- Department of Neurology, Fujian Medical University Union Hospital, Fuzhou, China.,Institute of Cerebral Vascular Diseases of Fujian Province, Fuzhou, China.,Key Laboratory of Brain Aging and Neurodegenerative Diseases, Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, China
| | - Peiqiang Lin
- Department of Neurology, Fujian Medical University Union Hospital, Fuzhou, China.,Institute of Cerebral Vascular Diseases of Fujian Province, Fuzhou, China.,Key Laboratory of Brain Aging and Neurodegenerative Diseases, Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, China
| | - Mouwei Zheng
- Department of Neurology, Fujian Medical University Union Hospital, Fuzhou, China.,Institute of Cerebral Vascular Diseases of Fujian Province, Fuzhou, China.,Key Laboratory of Brain Aging and Neurodegenerative Diseases, Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, China
| | - Yongxing Lai
- Department of Neurology, Fujian Medical University Union Hospital, Fuzhou, China.,Institute of Cerebral Vascular Diseases of Fujian Province, Fuzhou, China.,Key Laboratory of Brain Aging and Neurodegenerative Diseases, Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, China
| | - Manli Chen
- Department of Neurology, Fujian Medical University Union Hospital, Fuzhou, China.,Institute of Cerebral Vascular Diseases of Fujian Province, Fuzhou, China.,Key Laboratory of Brain Aging and Neurodegenerative Diseases, Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, China
| | - Yixian Zhang
- Department of Rehabilitation, Fujian Medical University Union Hospital, Fuzhou, China.,Institute of Cerebral Vascular Diseases of Fujian Province, Fuzhou, China.,Key Laboratory of Brain Aging and Neurodegenerative Diseases, Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, China
| | - Jianhao Chen
- Department of Neurology, Fujian Medical University Union Hospital, Fuzhou, China.,Institute of Cerebral Vascular Diseases of Fujian Province, Fuzhou, China.,Key Laboratory of Brain Aging and Neurodegenerative Diseases, Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, China
| | - Xiaohui Lin
- Department of Neurology, Fujian Medical University Union Hospital, Fuzhou, China.,Institute of Cerebral Vascular Diseases of Fujian Province, Fuzhou, China.,Key Laboratory of Brain Aging and Neurodegenerative Diseases, Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, China
| | - Longzai Lin
- Department of Neurology, Fujian Medical University Union Hospital, Fuzhou, China.,Institute of Cerebral Vascular Diseases of Fujian Province, Fuzhou, China.,Key Laboratory of Brain Aging and Neurodegenerative Diseases, Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, China
| | - Quan Lan
- Department of Neurology, Fujian Medical University Union Hospital, Fuzhou, China.,Institute of Cerebral Vascular Diseases of Fujian Province, Fuzhou, China.,Key Laboratory of Brain Aging and Neurodegenerative Diseases, Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, China.,Department of Neurology, The First Affiliated Hospital of Xiamen University, Xiamen, China
| | - Qilin Yuan
- Department of Neurology, Fujian Medical University Union Hospital, Fuzhou, China.,Institute of Cerebral Vascular Diseases of Fujian Province, Fuzhou, China.,Key Laboratory of Brain Aging and Neurodegenerative Diseases, Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, China
| | - Ronghua Chen
- Department of Neurology, Fujian Medical University Union Hospital, Fuzhou, China.,Institute of Cerebral Vascular Diseases of Fujian Province, Fuzhou, China.,Key Laboratory of Brain Aging and Neurodegenerative Diseases, Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, China
| | - Xinhong Jiang
- Department of Rehabilitation, Fujian Medical University Union Hospital, Fuzhou, China.,Institute of Cerebral Vascular Diseases of Fujian Province, Fuzhou, China.,Key Laboratory of Brain Aging and Neurodegenerative Diseases, Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, China
| | - Yingchun Xiao
- Department of Neurology, Fujian Medical University Union Hospital, Fuzhou, China.,Institute of Cerebral Vascular Diseases of Fujian Province, Fuzhou, China.,Key Laboratory of Brain Aging and Neurodegenerative Diseases, Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, China
| | - Nan Liu
- Department of Neurology, Fujian Medical University Union Hospital, Fuzhou, China.,Department of Rehabilitation, Fujian Medical University Union Hospital, Fuzhou, China.,Institute of Cerebral Vascular Diseases of Fujian Province, Fuzhou, China.,Key Laboratory of Brain Aging and Neurodegenerative Diseases, Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, China
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Zou YY, Kan EM, Cao Q, Lu J, Ling EA. Combustion smoke-induced inflammation in the cerebellum and hippocampus of adult rats. Neuropathol Appl Neurobiol 2014; 39:531-52. [PMID: 23106634 DOI: 10.1111/nan.12001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2012] [Accepted: 10/23/2012] [Indexed: 12/12/2022]
Abstract
AIMS The effect of combustion smoke inhalation on the respiratory system is widely reported but its effects on the central nervous system remain unclear. Here, we aimed to determine the effects of smoke inhalation on the cerebellum and hippocampus which are areas vulnerable to hypoxia injury. METHODS Adult male Sprague-Dawley rats were subjected to combustion smoke inhalation and sacrificed at 0.5, 3, 24 and 72 h after exposure. The cerebellum and hippocampus were subjected to Western analysis for VEGF, iNOS, eNOS, nNOS and AQP4 expression; ELISA analysis for cytokine and chemokine levels; and immunohistochemistry for GFAP/AQP4, RECA-1/RITC and TUNEL. Aminoguanidine (AG) was administered to determine the effects of iNOS after smoke inhalation. RESULTS Both the cerebellum and hippocampus showed a significant increase in VEGF, iNOS, eNOS, nNOS and AQP4 expression with corresponding increases in inflammatory cytokines and chemokines and increased AQP4 expression and RITC permeability after smoke exposure. AG was able to decrease the expression of iNOS, followed by VEGF, eNOS, nNOS, RITC and AQP4 after smoke exposure. There was also a significant increase in TUNEL+ cells in the cerebellum and hippocampus which were not significantly reduced by AG. Beam walk test revealed immediate deficits after smoke inhalation which was attenuated with AG. CONCLUSION The findings suggest that iNOS plays a major role in the central nervous system inflammatory pathophysiology after smoke inhalation exposure with concomitant increase in proinflammatory molecules, vascular permeability and oedema, for which the cerebellum appears to be more vulnerable to smoke exposure than the hippocampus.
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Affiliation(s)
- Y-Y Zou
- Department of Pathology, Faculty of Basic Medical Sciences, Kunming Medical University, Kunming, China
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8
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Infante SK, Rea HC, Perez-Polo JR. Transgenerational effects of neonatal hypoxia-ischemia in progeny. Int J Dev Neurosci 2013; 31:398-405. [PMID: 23470326 DOI: 10.1016/j.ijdevneu.2013.02.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2012] [Revised: 02/06/2013] [Accepted: 02/12/2013] [Indexed: 10/27/2022] Open
Abstract
Neonatal hypoxia-ischemia (HI) affects 60% of low birth weight infants and up to 40% of preterm births. Cell death and brain injury after HI have been shown to cause long-lasting behavioral deficits. By using a battery of behavioral tests on second generation 3-week-old rodents, we found that neonatal HI is associated with behavioral outcomes in the progeny of HI-affected parents. Our results suggest an epigenetic transfer mechanism of some of the neurological symptoms associated with neonatal HI. Elucidating the transfer of brain injury to the next generation after HI calls attention to the risks associated with HI injury and the need for proper treatment to reverse these effects. Assessing the devastating extent of HI's reach serves as a cautionary tale to the risks associated with neonatal HI, and provides an incentive to create improved therapeutic measures to treat HI.
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Affiliation(s)
- Smitha K Infante
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555, United States
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9
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Kagias K, Nehammer C, Pocock R. Neuronal responses to physiological stress. Front Genet 2012; 3:222. [PMID: 23112806 PMCID: PMC3481051 DOI: 10.3389/fgene.2012.00222] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2012] [Accepted: 10/05/2012] [Indexed: 12/15/2022] Open
Abstract
Physiological stress can be defined as any external or internal condition that challenges the homeostasis of a cell or an organism. It can be divided into three different aspects: environmental stress, intrinsic developmental stress, and aging. Throughout life all living organisms are challenged by changes in the environment. Fluctuations in oxygen levels, temperature, and redox state for example, trigger molecular events that enable an organism to adapt, survive, and reproduce. In addition to external stressors, organisms experience stress associated with morphogenesis and changes in inner chemistry during normal development. For example, conditions such as intrinsic hypoxia and oxidative stress, due to an increase in tissue mass, have to be confronted by developing embryos in order to complete their development. Finally, organisms face the challenge of stochastic accumulation of molecular damage during aging that results in decline and eventual death. Studies have shown that the nervous system plays a pivotal role in responding to stress. Neurons not only receive and process information from the environment but also actively respond to various stresses to promote survival. These responses include changes in the expression of molecules such as transcription factors and microRNAs that regulate stress resistance and adaptation. Moreover, both intrinsic and extrinsic stresses have a tremendous impact on neuronal development and maintenance with implications in many diseases. Here, we review the responses of neurons to various physiological stressors at the molecular and cellular level.
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Affiliation(s)
- Konstantinos Kagias
- Biotech Research and Innovation Centre, University of Copenhagen Copenhagen, Denmark
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10
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Transcriptional regulation mechanisms of hypoxia-induced neuroglobin gene expression. Biochem J 2012; 443:153-64. [PMID: 22239089 DOI: 10.1042/bj20111856] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Ngb (neuroglobin) has been identified as a novel endogenous neuroprotectant. However, little is known about the regulatory mechanisms of Ngb expression, especially under conditions of hypoxia. In the present study, we located the core proximal promoter of the mouse Ngb gene to a 554 bp segment, which harbours putative conserved NF-κB (nuclear factor κB)- and Egr1 (early growth-response factor 1) -binding sites. Overexpression and knockdown of transcription factors p65, p50, Egr1 or Sp1 (specificity protein 1) increased and decreased Ngb expression respectively. Experimental assessments with transfections of mutational Ngb gene promoter constructs, as well as EMSA (electrophoretic mobility-shift assay) and ChIP (chromatin immunoprecipitation) assays, demonstrated that NF-κB family members (p65, p50 and cRel), Egr1 and Sp1 bound in vitro and in vivo to the proximal promoter region of the Ngb gene. Moreover, a κB3 site was found as a pivotal cis-element responsible for hypoxia-induced Ngb promoter activity. NF-κB (p65) and Sp1 were also responsible for hypoxia-induced up-regulation of Ngb expression. Although there are no conserved HREs (hypoxia-response elements) in the promoter of the mouse Ngb gene, the results of the present study suggest that HIF-1α (hypoxia-inducible factor-1α) is also involved in hypoxia-induced Ngb up-regulation. In conclusion, we have identified that NF-κB, Egr1 and Sp1 played important roles in the regulation of basal Ngb expression via specific interactions with the mouse Ngb promoter. NF-κB, Sp1 and HIF-1α contributed to the up-regulation of mouse Ngb gene expression under hypoxic conditions.
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11
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Perez-Polo JR, Reilly CB, Rea HC. Oxygen resuscitation after hypoxia ischemia stimulates prostaglandin pathway in rat cortex. Int J Dev Neurosci 2011; 29:639-44. [PMID: 21514373 PMCID: PMC3158954 DOI: 10.1016/j.ijdevneu.2011.03.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2011] [Revised: 03/21/2011] [Accepted: 03/29/2011] [Indexed: 12/31/2022] Open
Abstract
Exposure to hypoxia and hyperoxia in a rodent model of perinatal ischemia results in delayed cell death and inflammation. Hyperoxia increases oxidative stress that can trigger inflammatory cascades, neutrophil activation, and brain microvascular injury. Here we show that 100% oxygen resuscitation in our rodent model of perinatal ischemia increases cortical COX-2 protein levels, S-nitrosylated COX-2cys526, PGE2, iNOS and 5-LOX, all components of the prostaglandin and leukotriene inflammatory pathway.
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12
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Chen X, Zhou C, Guo J, Sun K, Zhao N, Yang J, Sun Y, Liu X, Hibi T, Liu Z, Han J. Effects of dihydroxylphenyl lactic acid on inflammatory responses in spinal cord injury. Brain Res 2010; 1372:160-8. [PMID: 21134362 DOI: 10.1016/j.brainres.2010.11.089] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2010] [Revised: 11/21/2010] [Accepted: 11/25/2010] [Indexed: 11/27/2022]
Abstract
The initial mechanical tissue disruption of spinal cord injury (SCI) is followed by a period of secondary injury that increases the size of the lesion. Secondary injuries are associated with edema, inflammation, excessive cytokine release, excitotoxicity and cell apoptosis. 3,4-dihydroxyphenyl lactic acid (DLA) is one of the major water-soluble components of chemical constituents from Salvia miltiorrhiza (SM). To investigate the inhibition effects of DLA on secondary injury of SCI, focusing especially on suppression of inflammatory responses and the mechanism of this effect, the following studies were performed: Basso, Beattie, and Bresnahan (BBB) scores to assess motor functions till 10 days after SCI; Nissl and Fast Blue histological staining and immunohistochemistry of inhibitory-kappa B-alpha (IκB-α) and nuclear factor-kappa B (NF-κB) p65 subunit protein; levels of myeloperoxidase (MPO) activity analysis as an indicator of polymorphonuclear infiltration; IL-6 production in plasma 10 days after SCI; Western blot analysis to determine cytoplasm levels of IκB-α and NF-κB p65 subunit proteins in the nuclear fractions 10 days after SCI. DLA significantly attenuated the motor function and tissue damage following SCI in rats, significant reduced polymorphonuclear cell infiltration and IL-6 production, as well as reduced cytoplasm IκB-α degradation and the nuclear translocation of NF-κB p65 subunit protein after SCI. In conclusion, the results clearly demonstrate that DLA inhibit the inflammation responses induced by SCI via inhibiting effect of production of IL-6 and nuclear translocation of NF-κB.
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Affiliation(s)
- Xin Chen
- Orthopaedic Department, Peking University Third Hospital, Beijing, China
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13
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Ferrari DC, Nesic OB, Perez-Polo JR. Oxygen resuscitation does not ameliorate neonatal hypoxia/ischemia-induced cerebral edema. J Neurosci Res 2010; 88:2056-65. [PMID: 20143414 DOI: 10.1002/jnr.22358] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Neonatal hypoxia/ischemia (HI) is a common cause of cognitive and behavioral deficits in children with hyperoxia treatment (HHI) being the current therapy for newborn resuscitation. HI induces cerebral edema that is associated with poor neurological outcomes. Our objective was to characterize cerebral edema after HI and determine the consequences of HHI (40% or 100% O(2)). Dry weight analyses showed cerebral edema 1 to 21 days after HI in the ipsilateral cortex; and 3 to 21 days after HI in the contralateral cortex. Furthermore, HI increased blood-brain barrier (BBB) permeability 1 to 7 days after HI, leading to bilateral cortical vasogenic edema. HHI failed to prevent HI-induced increase in BBB permeability and edema development. At the molecular level, HI increased ipsilateral, but not contralateral, AQP4 cortical levels at 3 and up to 21 days after HI. HHI treatment did not further affect HI-induced changes in AQP4. In addition, we observed developmental increases of AQP4 accompanied by significant reduction in water content and increase permeability of the BBB. Our results suggest that the ipsilateral HI-induced increase in AQP4 may be beneficial and that its absence in the contralateral cortex may account for edema formation after HI. Finally, we showed that HI induced impaired motor coordination 21 days after the insult and HHI did not ameliorate this behavioral outcome. We conclude that HHI treatment is effective as a resuscitating therapy, but does not ameliorate HI-induced cerebral edema and impaired motor coordination.
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Affiliation(s)
- Diana Carolina Ferrari
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch at Galveston, 301 University Boulevard, Galveston, TX 77555-1072, USA
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14
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Mao XR, Moerman-Herzog AM, Chen Y, Barger SW. Unique aspects of transcriptional regulation in neurons--nuances in NFkappaB and Sp1-related factors. J Neuroinflammation 2009; 6:16. [PMID: 19450264 PMCID: PMC2693111 DOI: 10.1186/1742-2094-6-16] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2009] [Accepted: 05/18/2009] [Indexed: 12/11/2022] Open
Abstract
The unique physiology and function of neurons create differences in their cellular physiology, including their regulation of gene expression. We began several years ago exploring the relationships between the NFκB transcription factor, neuronal survival, and glutamate receptor activation in telencephalic neurons. These studies led us to conclude that this population of cells is nearly incapable of activating the NFκB that is nonetheless expressed at reasonable levels. A subset of the κB cis elements are instead bound by members of the Sp1 family in neurons. Also surprising was our discovery that Sp1 itself, typically described as ubiquitous, is severely restricted in expression within forebrain neurons; Sp4 seems to be substituted during neuronal differentiation. These findings and their implications for neuronal differentiation – as well as potential dedifferentiation during degenerative processes – are discussed here.
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Affiliation(s)
- Xianrong R Mao
- Department of Anesthesiology, Washington University School of Medicine, St Louis, MO 63110, USA.
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15
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Sarnico I, Lanzillotta A, Boroni F, Benarese M, Alghisi M, Schwaninger M, Inta I, Battistin L, Spano P, Pizzi M. NF-kappaB p50/RelA and c-Rel-containing dimers: opposite regulators of neuron vulnerability to ischaemia. J Neurochem 2009; 108:475-85. [PMID: 19094066 DOI: 10.1111/j.1471-4159.2008.05783.x] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Diverse nuclear factor-kappaB subunits mediate opposite effects of extracellular signals on neuron survival. While RelA is activated by neurotoxic agents, c-Rel drives neuroprotective effects. In brain ischaemia RelA and p50 factors rapidly activate, but how they associate with c-Rel to form active dimers and contribute to the changes in diverse dimer activation for neuron susceptibility is unknown. We show that in both cortical neurons exposed to oxygen glucose deprivation (OGD) and mice subjected to brain ischaemia, activation of p50/RelA was associated with inhibition of c-Rel/RelA dimer and no change p50/c-Rel. Targeting c-Rel and RelA expression revealed that c-Rel dimers reduced while p50/RelA enhanced neuronal susceptibility to anoxia. Activation of p50/RelA complex is known to induce the pro-apoptotic Bim and Noxa genes. We now show that c-Rel-containing dimers, p50/c-Rel and RelA/c-Rel, but not p50/RelA, promoted Bcl-xL transcription. Accordingly, the OGD exposure induced Bim, but reduced Bcl-xL promoter activity and decreased the content of endogenous Bcl-xL protein. These findings demonstrate that within the same neuronal cell, the balance between activation of p50/RelA and c-Rel-containing complexes fine tunes the threshold of neuron vulnerability to the ischaemic insult. Selective targeting of different dimers will unravel new approaches to limit ischaemia-associated apoptosis.
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Affiliation(s)
- Ilenia Sarnico
- Division of Pharmacology and Experimental Therapeutics, Department of Biomedical Sciences & Biotechnologies, School of Medicine, University of Brescia, Viale Europa 11, Brescia, Italy
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16
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Pizzi M, Sarnico I, Lanzillotta A, Battistin L, Spano P. Post-ischemic brain damage: NF-kappaB dimer heterogeneity as a molecular determinant of neuron vulnerability. FEBS J 2009; 276:27-35. [PMID: 19087197 DOI: 10.1111/j.1742-4658.2008.06767.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Nuclear factor-kappaB (NF-kappaB) has been proposed to serve a dual function as a regulator of neuron survival in pathological conditions associated with neurodegeneration. NF-kappaB is a transcription family of factors comprising five different proteins, namely p50, RelA/p65, c-Rel, RelB and p52, which can combine differently to form active dimers in response to external stimuli. Recent research shows that diverse NF-kappaB dimers lead to cell death or cell survival in neurons exposed to ischemic injury. While the p50/p65 dimer participates in the pathogenesis of post-ischemic injury by inducing pro-apoptotic gene expression, c-Rel-containing dimers increase neuron resistance to ischemia by inducing anti-apoptotic gene transcription. We present, in this report, the latest findings and consider the therapeutic potential of targeting different NF-kappaB dimers to limit ischemia-associated neurodegeneration.
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Affiliation(s)
- Marina Pizzi
- Division of Pharmacology and Experimental Therapeutics, Department of Biomedical Sciences and Biotechnologies, School of Medicine, University of Brescia, Italy.
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17
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Fan W, Cooper NGF. Glutamate-induced NFkappaB activation in the retina. Invest Ophthalmol Vis Sci 2008; 50:917-25. [PMID: 18836176 DOI: 10.1167/iovs.08-2555] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
PURPOSE To determine the distribution and glutamate-mediated activation of nuclear factor (NF) kappaB members in the retina and pan-purified retinal ganglion cells (RGCs) and to characterize steps in the signal transduction events that lead to NFkappaB activation. METHODS Retinal expression patterns and RGCs were evaluated for five NFkappaB proteins with the aid of immunohistochemistry. Retinal explants or RGCs were treated with glutamate with or without the presence of the NDMA receptor antagonist memantine, the calcium chelator EGTA, or a specific inhibitor for calcium/calmodulin-dependent protein kinase-II (CaMKII). Characterizations of NFkappaB activation were performed with the aid of electrophoretic mobility shift assays and supershift assays. RESULTS All five NFkappaB proteins were present in the retina and in the pan-purified RGCs. In response to a glutamate stimulus, all NFkappaB proteins except c-Rel were activated. P65 was unique in that it was not constitutively active but showed a glutamate-inducible activation in the retina and in the cultured RGCs. Memantine, EGTA, or autocamtide-2-related inhibitory peptide (AIP) inhibited NFkappaB activation in the retina. Furthermore, AIP significantly reduced the level of glutamate-induced degradation of IkappaBs. CONCLUSIONS These data indicate that glutamate activates distinct NFkappaB proteins in the retina. P65 activation may be especially important with regard to RGC responses to glutamate given that its activity is induced by conditions known to lead to the death of these cells. The NMDA receptor-Ca(2+)-CaMKII signaling pathway is involved in glutamate-induced NFkappaB activation. Because AIP blocks the degradation of IkappaB, its regulation is clearly downstream of CaMKII.
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Affiliation(s)
- Wei Fan
- Department of Anatomical Sciences and Neurobiology, University of Louisville School of Medicine, Louisville, Kentucky 40202, USA
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18
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Rafati DS, Geissler K, Johnson K, Unabia G, Hulsebosch C, Nesic-Taylor O, Perez-Polo JR. Nuclear factor-kappaB decoy amelioration of spinal cord injury-induced inflammation and behavior outcomes. J Neurosci Res 2008; 86:566-80. [PMID: 17918744 DOI: 10.1002/jnr.21508] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Spinal cord injury (SCI) results in a pathophysiology characterized by multiple locomotor and sensory deficits, resulting in altered nociception and hyperalgesia. SCI triggers an early and prolonged inflammatory response, with increased interleukin-1beta levels. Transient changes are observed in subunit populations of the transcription factor nuclear factor-kappaB (NF-kappaB). There were decreases in neuronal c-Rel levels and inverse increases in p65 and p50 levels. There were no changes in neuronal p52 or RelB subunits after SCI at any time point tested. Similarly, SCI had no effect on oligodendroglial levels of any NF-kappaB subunit. There were significant early increases in COX-2 and inducible nitric oxide synthase mRNA and protein levels after SCI. We used synthetic double-stranded "decoy" deoxyoligonucleotides containing selective NF-kappaB protein dimer binding consensus sequences. Decoys targeting the p65/p50 binding site on the COX-2 promoter decreased SCI-induced cell losses, NF-kappaB p65/p50 DNA-binding activity, and COX-2 and iNOS protein levels. NF-kappaB p65/p50 targeted decoys improved early locomotor recovery after moderate but not severe SCI, yet ameliorated SCI-induced hypersensitization after both moderate and severe SCI. To determine whether changes in GABA activity played a role in decreased hypersensitivity after SCI and p65/p50 targeted decoy, we counted gamma-aminobutyric acid (GABA)-containing neurons in laminae 1-3. There were significantly more GABAergic neurons in the p65/p50 targeted decoy-treated group at the level of injury.
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Affiliation(s)
- Danny Salah Rafati
- Department of Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, Texas, USA
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19
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Song YS, Lee YS, Narasimhan P, Chan PH. Reduced oxidative stress promotes NF-kappaB-mediated neuroprotective gene expression after transient focal cerebral ischemia: lymphocytotrophic cytokines and antiapoptotic factors. J Cereb Blood Flow Metab 2007; 27:764-75. [PMID: 16868554 PMCID: PMC1831759 DOI: 10.1038/sj.jcbfm.9600379] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Nuclear factor-kappa B (NF-kappaB) is activated by oxidative stress such as that induced by transient focal cerebral ischemia (tFCI). Whether NF-kappaB has a role in cell survival or death in stroke is a matter of debate. We proposed that the status of oxidative stress may determine its role in cell death or survival after focal ischemia. To characterize the coordinated expression of genes in NF-kappaB signaling after mild cerebral ischemia, we investigated the temporal profile of a NF-kappaB-pathway-focused DNA array after 30 mins of tFCI in wild-type (WT) mice and human copper/zinc-superoxide dismutase transgenic (SOD1 Tg) mice that had a significantly reduced level of superoxide. Differentially expressed genes among 96 NF-kappaB-related genes were further confirmed and compared in the WT and SOD1 Tg mice using quantitative polymerase chain reaction, Western blotting, and immunohistochemistry. Persistent upregulation of NF-kappaB seen at 7 days in the WT mice was decreased in the SOD1 Tg mice. Lymphocytotrophic cytokine genes such as interleukin-2, interleukin-12, and interferon-alpha1 were increased in the SOD1 Tg mice compared with the WT mice after tFCI. In addition, antiapoptosis factors bcl-2 and tumor necrosis factor receptor-associated factor 1 rapidly increased in the SOD1 Tg mice compared with the WT mice. This study indicates that reduced oxidative stress by SOD1 overexpression increased NF-kappaB-related rapid defenses, such as immune response and antiapoptosis factors, and prevented brain damage after tFCI-induced oxidative stress.
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Affiliation(s)
| | | | | | - Pak H Chan
- Correspondence: Dr Pak H Chan, Neurosurgical Laboratories, Stanford University, 1201 Welch Rd., MSLS #P314, Stanford, CA 94305-5487, USA. Phone: (650) 498-4457; fax: (650) 498-4550. E-mail:
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20
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Bourne KZ, Ferrari DC, Lange-Dohna C, Rossner S, Wood TG, Perez-Polo JR. Differential regulation of BACE1 promoter activity by nuclear factor-κB in neurons and glia upon exposure to β-amyloid peptides. J Neurosci Res 2007; 85:1194-204. [PMID: 17385716 DOI: 10.1002/jnr.21252] [Citation(s) in RCA: 151] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The brains of Alzheimer's disease (AD) patients display cerebrovascular and parenchymal deposits of beta-amyloid (A beta) peptides, which are derived by proteolytic processing by the beta-site APP-cleaving enzyme 1 (BACE1) of the amyloid precursor protein (APP). The rat BACE1 promoter has a nuclear factor-kappaB (NF-kappaB) binding site. Deletion studies with a BACE1 promoter/luciferase reporter suggest that the NF-kappaB binding DNA consensus sequence plays a suppressor role, when occupied by NF-kappaB, in the regulation of neuronal brain BACE1 expression. Here we characterize a signal transduction pathway that may be responsible for the increases in A beta associated with AD. We propose that the transcription factor NF-kappaB acts as a repressor in neurons but as an activator of BACE1 transcription in activated astrocytes present in the CNS under chronic stress, a feature present in the AD brain. The activated astrocytic stimulation of BACE1 may in part account for increased BACE1 transcription and subsequent processing of Ab eta in a cell-specific manner in the aged and AD brain. As measured by reporter gene promoter constructs and endogenous BACE1 protein expression, a functional NF-kappaB site was stimulatory in activated astrocytes and A beta-exposed neuronal cells and repressive in neuronal and nonactivated astrocytic cells. Given the evidence for increased levels of activated astrocytes in the aged brain, the age- and AD-associated increases in NF-kappaB in brain may be significant contributors to increases in A beta, acting as a positive feedback loop of chronic inflammation, astrocyte activation, increased p65/p50 activation of BACE1 transcription, and further inflammation.
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Affiliation(s)
- Krystyn Z Bourne
- Department of Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, TX 77555-1072, USA
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21
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Hu X, Rea HC, Wiktorowicz JE, Perez-Polo JR. Proteomic analysis of hypoxia/ischemia-induced alteration of cortical development and dopamine neurotransmission in neonatal rat. J Proteome Res 2006; 5:2396-404. [PMID: 16944952 PMCID: PMC3128998 DOI: 10.1021/pr060209x] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Perinatal hypoxia/ischemia (HI) is a common cause of neurological deficits in children. Our goal was to elucidate the underlying mechanisms that contribute to the neurological sequelae of HI-induced brain injury. HI was induced by permanent ligation of the left carotid artery followed by 90 min of hypoxia (7.8% O2) in female P7 rats. A two-dimensional differential proteome analysis was used to assess changes in protein expression in cortex 2 h after HI. In total, 17 proteins reflecting a 2-fold or higher perturbation of expression after HI as compared to sham-treated pups were identified by mass spectrometry. Of the altered proteins, 14-3-3epsilon and TUC-2, both playing an important role in the development of the central nervous system, decrease after HI, consistent with an early disturbance of cortical development. Also affected, DARPP-32 and alpha-synuclein, two proteins important for dopamine neurotransmission, increased more than 2-fold 2 h after HI injury. The differential expression of these proteins was validated by individual Western blot assays. The expression of several metabolic enzymes and translational factors was also perturbed early after HI brain injury. These findings provide initial insights into the mechanisms underlying neurodegenerative events after HI and may allow for the rational design of therapeutic strategies that enhance neuronal adaptation and compensation after HI.
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Affiliation(s)
| | | | | | - J. Regino Perez-Polo
- Corresponding Author: J. R. Perez-Polo, Ph.D., Galveston, Texas, 77555-1072 USA. Telephone: 409-772-3668. Fax: 409-772-8028.
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22
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Mémet S. NF-kappaB functions in the nervous system: from development to disease. Biochem Pharmacol 2006; 72:1180-95. [PMID: 16997282 DOI: 10.1016/j.bcp.2006.09.003] [Citation(s) in RCA: 147] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2006] [Revised: 08/31/2006] [Accepted: 09/05/2006] [Indexed: 01/01/2023]
Abstract
The transcription factor nuclear factor-kappaB (NF-kappaB) is an ubiquitously expressed dimeric molecule with post-translationally regulated activity. Its role in the immune system and host defense has been well characterized over the last two decades. In contrast, our understanding of the function of this transcription factor in the nervous system (NS) is only emerging. Given their cytoplasmic retention and nuclear translocation upon stimulus, NF-kappaB members are likely to exert an important role in transduction of signals from synaptic terminals to nucleus, to initiate transcriptional responses. This report describes recent findings deciphering the diverse functions of NF-kappaB in NS development and activity, which range from the control of cell growth, survival and inflammatory response to synaptic plasticity, behavior and cognition. Particular attention is given to the specific roles of NF-kappaB in the various cells of the NS, e.g. neurons and glia. Current knowledge of the contribution of NF-kappaB to several neurodegenerative disorders, such as Alzheimer's, Parkinson's and Huntington's diseases is also summarized.
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Affiliation(s)
- Sylvie Mémet
- Unité de Mycologie Moléculaire, FRE CNRS 2849, Department of Infection and Epidemiology, Institut Pasteur, 25 rue du Dr. Roux, 75724 Paris Cedex 15, France.
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23
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Menshanov PN, Bannova AV, Dygalo NN. Region-Specific Interrelations between Apoptotic Proteins Expression and DNA Fragmentation in the Neonatal Rat Brain. Neurochem Res 2006; 31:869-75. [PMID: 16794856 DOI: 10.1007/s11064-006-9089-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/09/2006] [Indexed: 12/20/2022]
Abstract
DNA fragmentation, mRNA and protein levels of Bcl-XL, Bax and caspase-3 were determined to characterize interrelations between expression of these apoptotic markers in the neonatal brain regions. High DNA fragmentation intensity in the cortex was in consonance with the lowest Bcl-XL/Bax expression ratio, the highest procaspase-3 and active caspase-3 levels. Low and intermediate DNA fragmentation levels in the cerebellum and hippocampus respectively were also in a good agreement with apoptotic proteins expression in these structures. In the cortex, hippocampus and cerebellum DNA fragmentation intensity was proportional to the active caspase-3 level. In contrast to these structures, in the brainstem, the lowest level of this protease was accompanied by the highest intensity of DNA fragmentation among the brain regions studied. The data suggest that cell death normally occurring during early postnatal life could be realized in the developing brainstem via caspase-3-independent pathways in animals that express this protease.
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Affiliation(s)
- Petr N Menshanov
- Functional Neurogenomics Laboratory, Institute of Cytology and Genetics, Russian Academy of Science, Novosibirsk, Russian Federation
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24
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Pizzi M, Spano P. Distinct roles of diverse nuclear factor-kappaB complexes in neuropathological mechanisms. Eur J Pharmacol 2006; 545:22-8. [PMID: 16854410 DOI: 10.1016/j.ejphar.2006.06.027] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2005] [Revised: 03/22/2006] [Accepted: 06/13/2006] [Indexed: 12/18/2022]
Abstract
The nuclear transcription factors kappaB (NF-kappaB) function as key regulators of physiological processes in the central nervous system. Aberrant regulation of NF-kappaB can underlie neurological disorders associated with neurodegeneration. A large number of studies have reported a dual role of NF-kappaB in regulating neuron survival in pathological conditions. A recent progress in understanding the mechanisms responsible for opposite effects elicited by NF-kappaB in brain dysfunctions arises from the identification of diverse NF-kappaB complexes specifically involved in the mechanism of neuronal cell death or cell survival. We here discuss the latest findings and consider the therapeutic potential of targeting distinct NF-kappaB complexes for the treatment of neurodegenerative disorders and memory dysfunctions.
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Affiliation(s)
- Marina Pizzi
- Division of Pharmacology and Experimental Therapeutics, Department of Biomedical Sciences and Biotechnologies, School of Medicine, University of Brescia, I 25123, Italy.
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25
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Massa PT, Aleyasin H, Park DS, Mao X, Barger SW. NFkappaB in neurons? The uncertainty principle in neurobiology. J Neurochem 2006; 97:607-18. [PMID: 16573643 PMCID: PMC2063440 DOI: 10.1111/j.1471-4159.2006.03810.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Nuclear factor kappaB (NFkappaB) is a dynamically modulated transcription factor with an extensive literature pertaining to widespread actions across species, cell types and developmental stages. Analysis of NFkappaB in a complex environment such as neural tissue suffers from a difficulty in simultaneously establishing both activity and location. Much of the available data indicate a profound recalcitrance of NFkappaB activation in neurons, as compared with most other cell types. Few studies to date have sought to distinguish between the various combinatorial dimers of NFkappaB family members. Recent research has illuminated the importance of these problems, as well as opportunities to move past them to the nuances manifest through variable activation pathways, subunit complexity and target sequence preferences.
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Affiliation(s)
- Paul T Massa
- Department of Neurology, State University of New York-Upstate Medical University, Syracuse, New York, USA
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26
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Briscoe T, Duncan J, Cock M, Choo J, Rice G, Harding R, Scheerlinck JPY, Rees S. Activation of NF-κB transcription factor in the preterm ovine brain and placenta after acute LPS exposure. J Neurosci Res 2006; 83:567-74. [PMID: 16435393 DOI: 10.1002/jnr.20757] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Intrauterine infection may be causally related to inflammation and injury of the fetal brain, however the mechanisms by which this occurs are unclear. We have investigated whether nuclear factor (NF)-kappaB, a transcription factor for proinflammatory cytokines, is activated in the fetal brain after acute LPS-exposure. At 95 days of gestation (term = approximately 147 days), 5 fetuses received a single intravenous bolus dose of LPS (1 microg/kg); 6 fetuses served as controls. Fetal blood samples were taken hourly for 6 hr post LPS-exposure to assess physiological status. Ewes and fetuses were then euthanased, placental and brain tissue examined histologically, and NF-kappaB activation assessed in several regions of the fetal brain using an electromobility shift assay (EMSA). Oxidative stress was measured using lipid peroxidation and 8-isoprostane biochemical assays and brain cytokine concentrations analysed by enzyme linked immunosorbent assay (ELISA). LPS-exposed fetuses (relative to controls) were hypoxemic and the haematocrit and lactate levels had increased. In the brains of LPS-exposed fetuses compared to controls, NF-kappaB binding activity was elevated in the hippocampus and the thalamus/basal ganglia; 8-isoprostane levels were elevated overall (P < 0.05) in the parietal/occipital/temporal lobes and thalamus/basal ganglia. TNF-alpha and IL-6 concentrations were not elevated, however, there was a tendency for an elevation of IFN-gamma concentrations in the thalamus/basal ganglia. IFN-gamma concentration was elevated (P < 0.05) in the plasma 4 hr after LPS-exposure. In the placenta, NF-kappaB binding activity was increased (P < 0.05). We conclude that acute systemic administration of LPS leads to increased binding activity of NF-kappaB subunits in specific regions of the fetal brain and in the placenta, but that there is no clear-cut relationship between this elevation and vulnerability to endotoxic damage.
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Affiliation(s)
- T Briscoe
- Department of Anatomy and Cell Biology, University of Melbourne, Victoria, Australia
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27
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Hu X, Nesic-Taylor O, Qiu J, Rea HC, Fabian R, Rassin DK, Perez-Polo JR. Activation of nuclear factor-kappaB signaling pathway by interleukin-1 after hypoxia/ischemia in neonatal rat hippocampus and cortex. J Neurochem 2005; 93:26-37. [PMID: 15773902 DOI: 10.1111/j.1471-4159.2004.02968.x] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Perinatal hypoxia/ischemia (HI) is a common cause of neurological deficits in children. Interleukin-1 (IL-1) activity has been implicated in HI-induced brain damage. However, the mechanisms underlying its action in HI have not been characterized. We used a 7-day-old rat model to elucidate the role of nuclear factor-kappaB (NF-kappaB) activation in HI stimulation of IL-1 signaling. HI was induced by permanent ligation of the left carotid artery followed by 90 min of hypoxia (7.8% O(2)). Using ELISA assays, we observed increased cell death and caspase 3 activity in hippocampus and cortex 3, 6, 12, 24 and 48 h post-HI. IL-1beta protein expression increased, beginning at 3 h after HI and lasting until 24 h post-HI in hippocampus and 12 h post-HI in cortex. Intracerebroventricular injection of 2 microg IL-1 receptor antagonist (IL-1Ra) 2 h after HI significantly reduced cell death and caspase 3 activity. Electrophoretic mobility shift assay analyses of hippocampus and cortex after HI for NF-kappaB activity showed increased p65/p50 DNA-binding activity at 24 h post-HI. Western blot analyses showed significant nuclear translocation of p65. Protein expression levels of two known inflammatory agents, inducible nitric oxide synthase and cycloxygenase 2, known to be transcriptionally regulated by NF-kappaB, also increased at 24 h after HI. All these HI-induced changes were reversed by IL-1Ra blockade of IL-1 signaling, consistent with IL-1 triggering of inflammatory apoptotic outcomes via NF-kappaB transcriptional activation. The observed increase in cytoplasmic phosphorylated inhibitor kappaBalpha (IkappaBalpha) and nuclear translocation of Bcl-3 24 h after HI was also significantly attenuated by IL-1Ra blockade, suggesting that HI-induced IL-1 activation of NF-kappaB is via both the degradation of IkappaBalpha and the nuclear translocation of Bcl-3.
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Affiliation(s)
- Xiaoming Hu
- Department of Anatomy and Neuroscience, University of Texas Medical Branch, Galveston, Texas, USA
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28
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Pizzi M, Sarnico I, Boroni F, Benarese M, Steimberg N, Mazzoleni G, Dietz GPH, Bähr M, Liou HC, Spano PF. NF-κB factor c-Rel mediates neuroprotection elicited by mGlu5 receptor agonists against amyloid β-peptide toxicity. Cell Death Differ 2005; 12:761-72. [PMID: 15818410 DOI: 10.1038/sj.cdd.4401598] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Opposite effects of nuclear factor-kappaB (NF-kappaB) on neuron survival rely on activation of diverse NF-kappaB factors. While p65 is necessary for glutamate-induced cell death, c-Rel mediates prosurvival effects of interleukin-1beta. However, it is unknown whether activation of c-Rel-dependent pathways reduces neuron vulnerability to amyloid-beta (Abeta), a peptide implicated in Alzheimer's disease pathogenesis. We show that neuroprotection elicited by activation of metabotropic glutamate receptors type 5 (mGlu5) against Abeta toxicity depends on c-Rel activation. Abeta peptide induced NF-kappaB factors p50 and p65. The mGlu5 agonists activated c-Rel, besides p50 and p65, and the expression of manganese superoxide dismutase (MnSOD) and Bcl-X(L). Targeting c-Rel expression by RNA interference suppressed the induction of both antiapoptotic genes. Targeting c-Rel or Bcl-X(L) prevented the prosurvival effect of mGlu5 agonists. Conversely, c-Rel overexpression or TAT-Bcl-X(L) addition rescued neurons from Abeta toxicity. These data demonstrate that mGlu5 receptor activation promotes a c-Rel-dependent antiapoptotic pathway responsible for neuroprotection against Abeta peptide.
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Affiliation(s)
- M Pizzi
- Division of Pharmacology and Experimental Therapeutics, Department of Biomedical Sciences and Biotechnologies, School of Medicine, University of Brescia, 25123 Brescia, Italy.
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29
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Lubin FD, Johnston LD, Sweatt JD, Anderson AE. Kainate mediates nuclear factor-kappa B activation in hippocampus via phosphatidylinositol-3 kinase and extracellular signal-regulated protein kinase. Neuroscience 2005; 133:969-81. [PMID: 15916859 DOI: 10.1016/j.neuroscience.2005.03.028] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2005] [Revised: 03/24/2005] [Accepted: 03/26/2005] [Indexed: 01/01/2023]
Abstract
The transcription factor nuclear factor-kappa B (NF-kappaB) is an inducible regulator of genes that plays a crucial role in the nervous system. Glutamate receptor stimulation is one well-described mechanism for NF-kappaB activation. In the studies presented here we used the glutamate analog, kainate to investigate the signaling mechanisms that couple to NF-kappaB activation in hippocampus. Kainate (250 nM) application to hippocampal slices elicited a time-dependent increase in nuclear NF-kappaB levels in areas CA3 and CA1, but not dentate, compared with controls. Further analysis focused on hippocampal area CA3, revealed increased NF-kappaB DNA binding activity in response to kainate stimulation. Supershift electrophoretic mobility shift assay indicated that the kainate-mediated NF-kappaB complex binding DNA was composed of p65, p50, and c-Rel subunits. Through inhibition studies we found that extracellular signal-regulated protein kinase (ERK) and phosphatidylinositol-3 kinase (PI3K) couple to basal and kainate-mediated NF-kappaB DNA binding activity in area CA3. Kainate elicited decreased total and increased phospho-inhibitor kappa B alpha (IkappaBalpha), suggesting that kainate-mediated activation of NF-kappaB is via the classical IkappaB kinase pathway. Interestingly, inhibition of ERK but not PI3K blocked the kainate-mediated increase in phospho-IkappaBalpha. Thus, our findings support a role for the ERK and PI3K pathways in kainate-mediated NF-kappaB activation in hippocampal area CA3, but these kinases may target the NF-kappaB pathway at different loci.
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Affiliation(s)
- F D Lubin
- The Cain Foundation Laboratories, Texas Children's Hospital, Department of Pediatrics, MC 3-6365, 1102 Bates Street, Houston, TX 77030-2399, USA
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Qiu J, Hu X, Nesic O, Grafe MR, Rassin DK, Wood TG, Perez-Polo JR. Effects of NF-kappaB oligonucleotide "decoys" on gene expression in P7 rat hippocampus after hypoxia/ischemia. J Neurosci Res 2004; 77:108-18. [PMID: 15197744 DOI: 10.1002/jnr.20156] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
"Decoy" oligonucleotides can be used as gene-specific nuclear factor (NF-kappaB) inhibitors to regulate gene expression. We applied two different decoy oligonucleotides that contained the NF-kappaB binding consensus sequences present in the immunoglobulin G (IgG)-kappaB and Bcl-x promoter into 7-day-old (P7) rat lateral ventricles before hypoxia/ischemia (HI) and compared their effects on gene expression in hippocampi to saline-treated, scrambled decoy-treated, or untreated hippocampi exposed to HI. Left hippocampi were collected at 12 hr after HI. Electrophoretic mobility shift assays (EMSAs) showed that the two decoy treatments had different effects on NF-kappaB binding to the IgG-kappaB and Bcl-x promoter-specific consensus sequences, respectively. We assessed the decoys' effects on gene expression 12 hr after HI using ribonuclease protection assays (RPAs) and Affymetrix DNA microarrays. RPAs showed that both decoys significantly decreased interleukin (IL)-1alpha mRNA levels but had no impact on IL-1beta, IL-6, and IL-10 mRNA levels. IgG-kappaB decoys significantly decreased tumor necrosis factor (TNF)-alpha and TNF-beta mRNA levels compared to minimal changes after treatment with Bcl-x decoys. DNA microarray analyses showed that Bcl-x decoy treatment significantly decreased Bcl-x(L) mRNA levels. The decreased Bcl-x(L) mRNA levels after Bcl-x decoy treatment was confirmed by RPA analysis. DNA microarray data also indicated that several other genes were affected by both decoys. Our results suggest that different NF-kappaB decoy treatments could differentially regulate transcriptional responses to central nervous system trauma. Careful design of decoy sequences, however, is essential to acquire selective effects on cell death outcome.
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Affiliation(s)
- Jingxin Qiu
- Department of Human Biological Chemistry and Genetics, University of Texas Medical Branch, Galveston, Texas 77555-0652, USA
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Payne TM, Molestina RE, Sinai AP. Inhibition of caspase activation and a requirement for NF-kappaB function in the Toxoplasma gondii-mediated blockade of host apoptosis. J Cell Sci 2003; 116:4345-58. [PMID: 12966169 DOI: 10.1242/jcs.00756] [Citation(s) in RCA: 99] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Mammalian cells infected with the protozoan parasite Toxoplasma gondii are resistant to many apoptotic stimuli transmitted along both the mitochondrial and death receptor pathways. Apoptosis, and its inhibition in infected cells, was examined using multiple morphological, molecular and biochemical approaches. The data strongly indicate manipulation of the host apoptotic machinery at multiple levels, focusing on the inhibition of host caspases. Activation of the pro-apoptotic caspase family of proteases is a biochemical hallmark of apoptosis. Caspase activation occurs in a highly ordered cascade triggered by the initiator caspases 8 and 9, which activate the executioner caspase, caspase 3. Our findings indicate a profound blockade of caspase activation and activity as the molecular basis for the inhibition of apoptosis in T.-gondii-infected cells. Caspase inhibition was demonstrated using multiple intrinsic and synthetic substrates. Although the specific inhibitory molecule remains to be identified, data indicate an absolute requirement for the host transcription factor NF-kappaB and, by extension, genes regulated by it. We propose that T. gondii activates the host survival response, thereby increasing the overall resistance of infected cells to apoptotic stimuli.
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Affiliation(s)
- T Matthew Payne
- Department of Microbiology, Immunology and Molecular Genetics, University of Kentucky College of Medicine, 800 Rose St, Lexington, KY 40536, USA
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Dasu MRK, Herndon DN, Nesic O, Perez-Polo JR. IGF-I gene transfer effects on inflammatory elements present after thermal trauma. Am J Physiol Regul Integr Comp Physiol 2003; 285:R741-6. [PMID: 12805089 DOI: 10.1152/ajpregu.00046.2003] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Major thermal injury results in severe prolonged responses with three components: a hypermetabolic response, inflammatory responses, and endogenous wound-healing processes. We showed that use of liposome-mediated gene transfer of the insulin-like growth factor I (IGF-I) reduces burn-induced inflammatory responses and enhances wound healing. In the present study, we found transient increased levels of IGF-I protein in rats exposed to thermal trauma via liposomal gene transfer in an effort to define the transcriptional events that occur after IGF-I delivery at the site of injury. The beneficial effects of IGF-I gene transfer act partly via amelioration of burn-induced inflammatory responses that mediate cell death through caspase-3 activity and Bax expression. IGF-I gene transfer induces selective stimulation of activation protein-1 DNA-binding activity and activation of antiapoptotic, but not inflammatory, NF-kappaB transcription factors. Data were consistent with our hypothesis that the beneficial effects of IGF-I gene transfer on burned rats act in part via activation protein-1 and NF-kappaB transcriptional regulation and the concordance between the results obtained with antiapoptotic, as opposed to the proapoptotic, sequences as well as the corresponding changes in measures of cell death via Bax and caspase-3 mechanisms.
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Affiliation(s)
- Mohan R K Dasu
- Shriners Hospitals for Children and Department of Surgery, Galveston, TX 77550, USA.
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Hu X, Qiu J, Grafe MR, Rea HC, Rassin DK, Perez-Polo JR. Bcl‐2 family members make different contributions to cell death in hypoxia and/or hyperoxia in rat cerebral cortex. Int J Dev Neurosci 2003; 21:371-7. [PMID: 14599483 DOI: 10.1016/s0736-5748(03)00089-3] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Hypoxic brain injury during fetal or neonatal development leads to damaged immature neurons and can result in cognitive or behavioral dysfunction. Hyperoxia therapy (treatment with oxygen) is commonly applied to infants with signs of perinatal hypoxia-anoxia. Both hypoxia and hyperoxia have been shown to result in apoptosis in the brains of rats in several animal models. One determinant of cellular commitment to cell death is the differential expression of the Bcl-2 family of proteins in response to trauma. Here, we characterize cell death and the expression of Bcl-2 homologous proteins in 7-day-old neonatal rat cerebral cortex after hypoxia (5% O(2) for 40 min) and/or hyperoxia (>95% O(2) for 2 h after hypoxia). The expression of Bcl-2 and Bcl-X(L), two anti-apoptotic proteins, decreased at 24 h after hypoxia. Bcl-X(L) increased after either hyperoxia or hypoxia+hyperoxia. We did not detect significant changes in the cytoplasmic levels of pro-apoptotic protein Bax after any of these three treatments. Using cell death ELISA and DNA FragEL assays, we observed increased cell death at 24h after hypoxia, hyperoxia or hypoxia+hyperoxia treatments. At 24 h after either hypoxia, hyperoxia or hypoxia+hyperoxia, caspase 3 activity also increased significantly. Our results suggest that both hypoxia and hyperoxia alone can induce cell death. The Bcl-2 --> cytochrome c --> caspase 3 pathway played a role in hypoxia-induced cell death, while other pathways may be involved in hyperoxia-induced cell death.
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Affiliation(s)
- Xiaoming Hu
- Department of Anatomy and Neuroscience, University of Texas Medical Branch, Galveston, TX 77555-0652, USA
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34
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Abstract
There is increasing evidence that some neuronal death after brain ischaemia is mediated by the action of cysteine-requiring aspartate-directed proteases (caspases), the proteases responsible for apoptosis in mammals, although this form of neuronal death is not always accompanied by the morphological changes that are typical of apoptosis in other tissues. Caspase-mediated neuronal death is more extensive after transient than permanent focal brain ischaemia and may contribute to delayed loss of neurons from the penumbral region of infarcts. The activation of caspases after brain ischaemia is largely consequent on the translocation of Bax, Bak, and other BH3-only members of the Bcl-2 family to the mitochondrial outer membrane and the release of cytochrome c, procaspase-9, and apoptosis activating factor-1 (Apaf-1) from the mitochondrial intermembrane space. How exactly ischaemia induces this translocation is still poorly understood. NF-kappaB, the c-jun N-terminal kinase-c-Jun pathway, p53, E2F1, and other transcription factors are probably all involved in regulating the expression of BH3-only proteins after brain ischaemia, and mitochondrial translocation of Bad from sequestering cytosolic proteins is promoted by inactivation of the serine-threonine kinase, Akt. Other processes that are probably involved in the activation of caspases after brain ischaemia include the mitochondrial release of the second mitochondrial activator of caspases (Smac) or direct inhibitor-of-apoptosis-binding protein with low pI (DIABLO), the accumulation of products of lipid peroxidation, a marked reduction in protein synthesis, and the aberrant reentry of neurons into the cell cycle. Non-caspase-mediated neuronal apoptosis may also occur, but there is little evidence to date that this makes a significant contribution to brain damage after ischaemia. The intracellular processes that contribute to caspase-mediated neuronal death after ischaemia are all potential targets for therapy. However, anti-apoptotic interventions in stroke patients will require detailed evaluation using a range of outcome measures, as some such interventions seem simply to delay neuronal death and others to preserve neurons but not neuronal function.
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Affiliation(s)
- Seth Love
- Department of Neuropathology, Institute of Clinical Neurosciences, Frenchay Hospital, BS16 1LE, Bristol, UK.
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Pizzi M, Goffi F, Boroni F, Benarese M, Perkins SE, Liou HC, Spano P. Opposing roles for NF-kappa B/Rel factors p65 and c-Rel in the modulation of neuron survival elicited by glutamate and interleukin-1beta. J Biol Chem 2002; 277:20717-23. [PMID: 11912207 DOI: 10.1074/jbc.m201014200] [Citation(s) in RCA: 128] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
The nuclear transcription factors NF-kappaB/Rel have been shown to function as key regulators of either cell death or survival in neuronal cells. Here, we investigated whether selective activation of diverse NF-kappaB/Rel family members might lead to distinct effects on neuron viability. In both cultured rat cerebellar granule cells and mouse hippocampal slices, we examined NF-kappaB/Rel activation induced by two opposing modulators of cell viability: 1) interleukin-1beta (IL-1beta), which promotes neuron survival and 2) glutamate, which can elicit toxicity. IL-1beta produced a prolonged stimulation of NF-kappaB/Rel factors by inducing both IkappaBalpha and IkappaBbeta degradation. Glutamate produced a delayed and transient activation of NF-kappaB/Rel, which was associated with a brief loss of IkappaBalpha. Moreover, IL-1beta activated the p50, p65, and c-Rel subunits of NF-kappaB/Rel, whereas glutamate activated only the p50 and p65 proteins. The inhibition of NF-kappaB/Rel protein expression by antisense oligonucleotides in cerebellar granule cells showed that p65 was involved in glutamate-mediated cell death, whereas c-Rel was essential for IL-1beta-preserved cell survival. Furthermore, the depletion of c-Rel in cultured neurons as well as in the hippocampus from the c-Rel(-/-) mouse converted the IL-1beta effect into toxicity. These findings suggest that, within a single neuron, the balance between cell death and survival in response to external stimuli may rely on the activation of distinct NF-kappaB/Rel proteins.
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Affiliation(s)
- Marina Pizzi
- Division of Pharmacology and Experimental Therapeutics, Department of Biomedical Sciences and Biotechnologies, School of Medicine, University of Brescia, 25123 Brescia, Italy.
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McInnis J, Wang C, Anastasio N, Hultman M, Ye Y, Salvemini D, Johnson KM. The role of superoxide and nuclear factor-kappaB signaling in N-methyl-D-aspartate-induced necrosis and apoptosis. J Pharmacol Exp Ther 2002; 301:478-87. [PMID: 11961046 DOI: 10.1124/jpet.301.2.478] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
N-Methyl-D-aspartate (NMDA) receptor-mediated cell death is complex, probably involving elements of necrosis and apoptosis. The mechanisms underlying this phenomenon are incompletely understood but have been suggested to involve reactive oxygen species such as nitric oxide and superoxide anion (O(2)) and nuclear factor-kappaB (NF-kappaB) signaling. In this study, we used a selective nonpeptidyl superoxide dismutase mimetic (M40403) and SN50, a peptide inhibitor of NF-kappaB translocation, to investigate the role of O(2) and the potential downstream signaling molecules in cell death induced by activation of the NMDA receptor. Application of NMDA to a mixed neuronal/glial forebrain culture resulted in an early increase in the release of cytoplasmic lactate dehydrogenase (LDH), which peaked at 4 h. This was followed by a reduction in mitochondrial metabolism of the dye MTT [3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide] that continued to decrease throughout the 20-h exposure. A substantial increase in DNA fragmentation as measured by an enzyme-linked immunosorbent assay (ELISA) specific for DNA-associated histone proteins (nucleosomes) was observed at 7 and 20 h. M40403 and SN50 blocked NMDA-induced changes in LDH release at 2, 4, and 20 h, MTT metabolism at 4 and 20 h, and DNA fragmentation at 20 h as measured by the ELISA and by an increase in terminal dUTP-nick end labeling. M40403 also prevented NMDA-induced nuclear transport of NF-kappaB and increased expression of Bax relative to Bcl-X(L). SN50 was also able to block NMDA-induced cell death as well as the increased Bax/Bcl-X(L) ratio. Time course studies and experiments with SN50 and M40403 suggest that O(2) production and NF-kappaB translocation may be involved in necrosis and apoptosis, but the latter also requires an increased expression of Bax. The ability of M40403 to prevent NMDA-induced cell death relatively early in this cascade suggests its potential therapeutic utility in central nervous systems diseases such as stroke that are associated with increased NMDA receptor-mediated production of O(2).
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Affiliation(s)
- Justin McInnis
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, Texas
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Glasgow JN, Qiu J, Rassin D, Grafe M, Wood T, Perez-Pol JR. Transcriptional regulation of the BCL-X gene by NF-kappaB is an element of hypoxic responses in the rat brain. Neurochem Res 2001; 26:647-59. [PMID: 11519724 DOI: 10.1023/a:1010987220034] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Signal transduction pathways that mediate neuronal commitment to apoptosis involve the nuclear factor kappa B (NF-kappaB) transcription factor. The bcl-x gene is a member of the bcl-2 family of genes that regulate apoptosis, and gives rise to two proteins, Bcl-XL and Bcl-XS, via alternative mRNA splicing. BCl-XL protein, like Bcl-2, is a dominant inhibitor of apoptotic cell death, whereas Bcl-XS promotes apoptosis. While there is high expression of Bcl-XL in the developing and adult brain, few transcriptional control elements have been identified in the bcl-x promoter. There are two functional nuclear factor-kappa B (NF-kappaB) DNA binding sites clustered upstream of the brain-specific transcription start site in the upstream promoter region of murine bcl-x. Recombinant NF-kappaB proteins bind to these sites. Also NF-kappaB overexpression, coupled with bcl-x promoter/reporter assays using a series of murine bcl-x promoter and deletion mutants, has identified the downstream 1.1kb of the bcl-x promoter as necessary for basal promoter activity and induction by NF-kappaB in support of the hypothesis that NF-kappaB can act to enhance BCl-XL expression via highly selective interactions with the bcl-x promoter, where NF-kappaB binding and promoter activation are dependent on specific DNA binding site sequences and NF-kappaB protein dimer composition. Hypoxia induces apoptosis in the hippocampus where the NF-kappaB dimers c-Rel/p50 and p50/pS0 bind to the bcl-x promoter NF-kappaB site.
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Affiliation(s)
- J N Glasgow
- Department of Human Biological Chemistry and Genetics, University of Texas Medical Branch, Galveston 77555-0652, USA
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