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Riddle A, Srivastava T, Wang K, Tellez E, O'Neill H, Gong X, O'Niel A, Bell JA, Raber J, Lattal M, Maylie J, Back SA. Mild neonatal hypoxia disrupts adult hippocampal learning and memory and is associated with CK2-mediated dysregulation of synaptic calcium-activated potassium channel KCNN2. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.10.602558. [PMID: 39071376 PMCID: PMC11275740 DOI: 10.1101/2024.07.10.602558] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/30/2024]
Abstract
Objective Although nearly half of preterm survivors display persistent neurobehavioral dysfunction including memory impairment without overt gray matter injury, the underlying mechanisms of neuronal or glial dysfunction, and their relationship to commonly observed cerebral white matter injury are unclear. We developed a mouse model to test the hypothesis that mild hypoxia during preterm equivalence is sufficient to persistently disrupt hippocampal neuronal maturation related to adult cellular mechanisms of learning and memory. Methods: Neonatal (P2) mice were exposed to mild hypoxia (8%O 2 ) for 30 min and evaluated for acute injury responses or survived until adulthood for assessment of learning and memory and hippocampal neurodevelopment. Results Neonatal mild hypoxia resulted in clinically relevant oxygen desaturation and tachycardia without bradycardia and was not accompanied by cerebral gray or white matter injury. Neonatal hypoxia exposure was sufficient to cause hippocampal learning and memory deficits and abnormal maturation of CA1 neurons that persisted into adulthood. This was accompanied by reduced hippocampal CA3-CA1 synaptic strength and LTP and reduced synaptic activity of calcium-sensitive SK2 channels, key regulators of spike timing dependent neuroplasticity, including LTP. Structural illumination microscopy revealed reduced synaptic density, but intact SK2 localization at the synapse. Persistent loss of SK2 activity was mediated by altered casein kinase 2 (CK2) signaling. Interpretation Clinically relevant mild hypoxic exposure in the neonatal mouse is sufficient to produce morphometric and functional disturbances in hippocampal neuronal maturation independently of white matter injury. Additionally, we describe a novel persistent mechanism of potassium channel dysregulation after neonatal hypoxia. Collectively our findings suggest an unexplored explanation for the broad spectrum of neurobehavioral, cognitive and learning disabilities that paradoxically persist into adulthood without overt gray matter injury after preterm birth.
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Cheng KM, Hsu WL, Ma YL, Liu YC, Lee EHY. Novel role of NCoR1 in impairing spatial memory through the mediation of a novel interacting protein DEC2. Cell Mol Life Sci 2024; 81:273. [PMID: 38900294 PMCID: PMC11335199 DOI: 10.1007/s00018-024-05321-0] [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: 02/10/2024] [Revised: 06/06/2024] [Accepted: 06/13/2024] [Indexed: 06/21/2024]
Abstract
Long-term memory formation requires de novo RNA and protein synthesis. Using differential display PCR, we found that the NCoR1 cDNA fragment is differentially expressed between fast learners and slow learners, with fast learners showing a lower expression level than slow learners in the water maze learning task. Fast learners also show lower NCoR1 mRNA and protein expression levels. In addition, spatial training decreases both NCoR1 mRNA and protein expression, whereas NCoR1 conditional knockout (cKO) mice show enhanced spatial memory. In studying the molecular mechanism, we found that spatial training decreases the association between NCoR1 and DEC2. Both NCoR1 and DEC2 suppress the expression of BDNF, integrin α3 and SGK1 through C/EBPα binding to their DNA promoters, but overexpression of DEC2 in NCoR1 cKO mice rescues the decreased expression of these proteins compared with NCoR1 loxP mice overexpressing DEC2. Further, spatial training decreases DEC2 expression. Spatial training also enhances C/EBPα binding to Bdnf, Itga3 and Sgk1 promoters, an effect also observed in fast learners, and both NCoR1 and DEC2 control C/EBPα activity. Whereas knockdown of BDNF, integrin α3 or SGK1 expression impairs spatial learning and memory, it does not affect Y-maze performance, suggesting that BDNF, integrin α3 and SGK1 are involved in long-term memory formation, but not short-term memory formation. Moreover, NCoR1 expression is regulated by the JNK/c-Jun signaling pathway. Collectively, our findings identify DEC2 as a novel interacting protein of NCoR1 and elucidate the novel roles and mechanisms of NCoR1 and DEC2 in negative regulation of spatial memory formation.
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Affiliation(s)
- Kuang-Min Cheng
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan
- Institute of Biomedical Sciences, Academia Sinica, Taipei, 115, Taiwan
| | - Wei-Lun Hsu
- Institute of Biomedical Sciences, Academia Sinica, Taipei, 115, Taiwan
| | - Yun-Li Ma
- Institute of Biomedical Sciences, Academia Sinica, Taipei, 115, Taiwan
| | - Yen-Chen Liu
- Institute of Biomedical Sciences, Academia Sinica, Taipei, 115, Taiwan
| | - Eminy H Y Lee
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan.
- Institute of Biomedical Sciences, Academia Sinica, Taipei, 115, Taiwan.
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Sokołowska P, Seweryn Karbownik M, Jóźwiak-Bębenista M, Dobielska M, Kowalczyk E, Wiktorowska-Owczarek A. Antidepressant mechanisms of ketamine's action: NF-κB in the spotlight. Biochem Pharmacol 2023; 218:115918. [PMID: 37952898 DOI: 10.1016/j.bcp.2023.115918] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Revised: 10/03/2023] [Accepted: 11/09/2023] [Indexed: 11/14/2023]
Abstract
Ketamine recently approved for therapy of treatment-resistant depression shows a complex and not fully understood mechanism of action. Apart from its classical glutamatergic N-methyl-D-aspartate receptor antagonistic action, it is thought that anti-inflammatory properties of the drug are of clinical relevance due to the contribution of activated inflammatory mediators to the pathophysiology of depression and non-responsiveness of a group of patients to current antidepressant therapies. In a search of the mechanism underlying anti-inflammatory effects of ketamine, the nuclear factor kappa B transcription factor (NF-κB) has been proposed as a target for ketamine. The NF-κB forms precisely regulated protein signaling cascades enabling a rapid response to cellular stimuli. In the central nervous systems, NF-κB signaling appears to have pleiotropic but double-edged functions: on the one hand it participates in the regulation of processes that are crucial in the treatment of depression, such as neuroplasticity, neurogenesis or neuronal survival, on the other - in the activation of neuroinflammation and cell death. Ketamine has been found to reduce inflammation mediated by NF-κB, leading to decreased level of pro-inflammatory cytokines and other inflammatory or stress mediators. Therefore, this review presents recent data on the significance of the NF-κB cascade in the mechanism of ketamine's action and its future perspectives in designing new strategies for the treatment of depression.
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Affiliation(s)
- Paulina Sokołowska
- Department of Pharmacology and Toxicology, Medical University of Lodz, 90-752 Lodz, Zeligowskiego 7/9, Poland.
| | - Michał Seweryn Karbownik
- Department of Pharmacology and Toxicology, Medical University of Lodz, 90-752 Lodz, Zeligowskiego 7/9, Poland
| | - Marta Jóźwiak-Bębenista
- Department of Pharmacology and Toxicology, Medical University of Lodz, 90-752 Lodz, Zeligowskiego 7/9, Poland
| | - Maria Dobielska
- Department of Pharmacology and Toxicology, Medical University of Lodz, 90-752 Lodz, Zeligowskiego 7/9, Poland
| | - Edward Kowalczyk
- Department of Pharmacology and Toxicology, Medical University of Lodz, 90-752 Lodz, Zeligowskiego 7/9, Poland
| | - Anna Wiktorowska-Owczarek
- Department of Pharmacology and Toxicology, Medical University of Lodz, 90-752 Lodz, Zeligowskiego 7/9, Poland
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Synaptamide Modulates Astroglial Activity in Mild Traumatic Brain Injury. Mar Drugs 2022; 20:md20080538. [PMID: 36005540 PMCID: PMC9410022 DOI: 10.3390/md20080538] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 08/17/2022] [Accepted: 08/18/2022] [Indexed: 11/16/2022] Open
Abstract
At present, the study of the neurotropic activity of polyunsaturated fatty acid ethanolamides (N-acylethanolamines) is becoming increasingly important. N-docosahexaenoylethanolamine (synaptamide, DHEA) is a highly active metabolite of docosahexaenoic acid (DHA) with neuroprotective, synaptogenic, neuritogenic, and anti-inflammatory properties in the nervous system. Synaptamide tested in the present study was obtained using a chemical modification of DHA isolated from squid Berryteuthis magister liver. The results of this study demonstrate the effects of synaptamide on the astroglial response to injury in the acute (1 day) and chronic (7 days) phases of mild traumatic brain injury (mTBI) development. HPLC-MS study revealed several times increase of synaptamide concentration in the cerebral cortex and serum of experimental animals after subcutaneous administration (10 mg/kg/day). Using immunohistochemistry, it was shown that synaptamide regulates the activation of GFAP- and S100β-positive astroglia, reduce nNOS-positive immunostaining, and stimulates the secretion of neurotrophin BDNF. Dynamics of superoxide dismutase production in synaptamide treatment confirm the antioxidant efficacy of the test compound. We found a decrease in TBI biomarkers such as GFAP, S100β, and IL-6 in the blood serum of synaptamide-treated experimental animals using Western blot analysis. The results indicate the high therapeutic potential of synaptamide in reducing the severity of the brain damage consequences.
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Qin C, Yang S, Chu YH, Zhang H, Pang XW, Chen L, Zhou LQ, Chen M, Tian DS, Wang W. Signaling pathways involved in ischemic stroke: molecular mechanisms and therapeutic interventions. Signal Transduct Target Ther 2022; 7:215. [PMID: 35794095 PMCID: PMC9259607 DOI: 10.1038/s41392-022-01064-1] [Citation(s) in RCA: 191] [Impact Index Per Article: 95.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 06/01/2022] [Accepted: 06/15/2022] [Indexed: 02/07/2023] Open
Abstract
Ischemic stroke is caused primarily by an interruption in cerebral blood flow, which induces severe neural injuries, and is one of the leading causes of death and disability worldwide. Thus, it is of great necessity to further detailly elucidate the mechanisms of ischemic stroke and find out new therapies against the disease. In recent years, efforts have been made to understand the pathophysiology of ischemic stroke, including cellular excitotoxicity, oxidative stress, cell death processes, and neuroinflammation. In the meantime, a plethora of signaling pathways, either detrimental or neuroprotective, are also highly involved in the forementioned pathophysiology. These pathways are closely intertwined and form a complex signaling network. Also, these signaling pathways reveal therapeutic potential, as targeting these signaling pathways could possibly serve as therapeutic approaches against ischemic stroke. In this review, we describe the signaling pathways involved in ischemic stroke and categorize them based on the pathophysiological processes they participate in. Therapeutic approaches targeting these signaling pathways, which are associated with the pathophysiology mentioned above, are also discussed. Meanwhile, clinical trials regarding ischemic stroke, which potentially target the pathophysiology and the signaling pathways involved, are summarized in details. Conclusively, this review elucidated potential molecular mechanisms and related signaling pathways underlying ischemic stroke, and summarize the therapeutic approaches targeted various pathophysiology, with particular reference to clinical trials and future prospects for treating ischemic stroke.
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Affiliation(s)
- Chuan Qin
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Sheng Yang
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Yun-Hui Chu
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Hang Zhang
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Xiao-Wei Pang
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Lian Chen
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Luo-Qi Zhou
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Man Chen
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Dai-Shi Tian
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
| | - Wei Wang
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
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Zhu M, Li N, Wang Y, Gao S, Wang J, Shen X. Regulation of inflammation by VEGF/BDNF signaling in mouse retinal Müller glial cells exposed to high glucose. Cell Tissue Res 2022; 388:521-533. [PMID: 35394215 DOI: 10.1007/s00441-022-03622-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Accepted: 03/25/2022] [Indexed: 11/02/2022]
Abstract
The inflammatory changes seem to play an important role in the development of diabetic retinopathy (DR). Anti-VEGF therapy has been testified to inhibit inflammation in animal models of diabetes, but the detailed mechanisms during this process are not yet clear. Müller glial cells (MGCs) in the mammalian retina are deeply involved in DR, while the BDNF overexpression reduces inflammation in diabetic mice. In this research, we aimed to explore the relationship between VEGF and BDNF in mouse retinal MGCs during inflammation of diabetes. We examined the expression of glutamine-synthetase (GS), glial fibrillary acidic protein (GFAP), vascular-endothelial growth factor (VEGF), interleukin-1beta (IL-1β), and tumor necrosis factor-alpha (TNF-α) at different time points after mouse retinal MGCs exposed to high glucose (25 mM). We also explored changes in the expression of brain-derived neurotrophic factor (BDNF), nuclear factor kappa B (NF-κB), IL-1β, and TNF-α in MGCs after treatments with anti-VEGF, VEGF siRNA, BDNF siRNA, BDNF recombination protein, and NF-κB inhibitor. In mouse retinal MGCs exposed to high glucose, BDNF was increased after treatments with anti-VEGF or VEGF siRNA. BDNF was decreased in MGCs from VEGF overexpressed mice. Moreover, the expressions of NF-κB, IL-1β, and TNF-α changed with BDNF: NF-κB, IL-1β, and TNF-α were increased after treatments with BDNF siRNA; NF-κB, IL-1β, and TNF-α were decreased after treatments with BDNF recombination protein. VEGF may regulate cytokines (IL-1β and TNF-α) by BDNF/NF-κB signaling pathway. The regulation of the VEGF/BDNF/NF-κB signaling pathway may be a significant therapeutic strategy for DR.
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Affiliation(s)
- Minqi Zhu
- Department of Ophthalmology, Shanghai Jiao Tong University Medical School Affiliated Ruijin Hospital, Shanghai, China
| | - Na Li
- Department of Ophthalmology, Shanghai Jiao Tong University Medical School Affiliated Ruijin Hospital, Shanghai, China
| | - Yanuo Wang
- Department of Ophthalmology, Shanghai Jiao Tong University Medical School Affiliated Ruijin Hospital, Shanghai, China
| | - Shuang Gao
- Department of Ophthalmology, Shanghai Jiao Tong University Medical School Affiliated Ruijin Hospital, Shanghai, China
| | - Jing Wang
- Department of Ophthalmology, Shanghai Jiao Tong University Medical School Affiliated Ruijin Hospital, Shanghai, China.
| | - Xi Shen
- Department of Ophthalmology, Shanghai Jiao Tong University Medical School Affiliated Ruijin Hospital, Shanghai, China.
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Gao L, Zhang Y, Sterling K, Song W. Brain-derived neurotrophic factor in Alzheimer's disease and its pharmaceutical potential. Transl Neurodegener 2022; 11:4. [PMID: 35090576 PMCID: PMC8796548 DOI: 10.1186/s40035-022-00279-0] [Citation(s) in RCA: 145] [Impact Index Per Article: 72.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Accepted: 01/01/2022] [Indexed: 12/14/2022] Open
Abstract
Synaptic abnormalities are a cardinal feature of Alzheimer's disease (AD) that are known to arise as the disease progresses. A growing body of evidence suggests that pathological alterations to neuronal circuits and synapses may provide a mechanistic link between amyloid β (Aβ) and tau pathology and thus may serve as an obligatory relay of the cognitive impairment in AD. Brain-derived neurotrophic factors (BDNFs) play an important role in maintaining synaptic plasticity in learning and memory. Considering AD as a synaptic disorder, BDNF has attracted increasing attention as a potential diagnostic biomarker and a therapeutical molecule for AD. Although depletion of BDNF has been linked with Aβ accumulation, tau phosphorylation, neuroinflammation and neuronal apoptosis, the exact mechanisms underlying the effect of impaired BDNF signaling on AD are still unknown. Here, we present an overview of how BDNF genomic structure is connected to factors that regulate BDNF signaling. We then discuss the role of BDNF in AD and the potential of BDNF-targeting therapeutics for AD.
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Affiliation(s)
- Lina Gao
- Shandong Collaborative Innovation Center for Diagnosis, Treatment and Behavioral Interventions of Mental Disorders, Institute of Mental Health, College of Pharmacy, Jining Medical University, Jining, 272067, Shandong, China
- Townsend Family Laboratories, Department of Psychiatry, The University of British Columbia, 2255 Wesbrook Mall, Vancouver, BC, V6T 1Z3, Canada
| | - Yun Zhang
- National Clinical Research Center for Geriatric Disorders, Xuanwu Hospital, Capital Medical University, Beijing, 100053, China
| | - Keenan Sterling
- Townsend Family Laboratories, Department of Psychiatry, The University of British Columbia, 2255 Wesbrook Mall, Vancouver, BC, V6T 1Z3, Canada
| | - Weihong Song
- Shandong Collaborative Innovation Center for Diagnosis, Treatment and Behavioral Interventions of Mental Disorders, Institute of Mental Health, College of Pharmacy, Jining Medical University, Jining, 272067, Shandong, China.
- Townsend Family Laboratories, Department of Psychiatry, The University of British Columbia, 2255 Wesbrook Mall, Vancouver, BC, V6T 1Z3, Canada.
- National Clinical Research Center for Geriatric Disorders, Xuanwu Hospital, Capital Medical University, Beijing, 100053, China.
- Institute of Aging, Key Laboratory of Alzheimer's Disease of Zhejiang Province, School of Mental Health and The Affiliated Kangning Hospital, Wenzhou Medical University, Wenzhou, 325000, Zhejiang, China.
- Oujiang Laboratory (Zhejiang Lab for Regenerative Medicine, Vision and Brain Health), Wenzhou, 325001, Zhejiang, China.
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Beneficial and Dimorphic Response to Combined HDAC Inhibitor Valproate and AMPK/SIRT1 Pathway Activator Resveratrol in the Treatment of ALS Mice. Int J Mol Sci 2022; 23:ijms23031047. [PMID: 35162978 PMCID: PMC8835218 DOI: 10.3390/ijms23031047] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 01/07/2022] [Accepted: 01/13/2022] [Indexed: 02/07/2023] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal adult-onset neurodegenerative disorder. There is no cure and current treatments fail to slow the progression of the disease. Epigenetic modulation in the acetylation state of NF-kB RelA and the histone 3 (H3) protein, involved in the development of neurodegeneration, is a drugable target for the class-I histone deacetylases (HDAC) inhibitors, entinostat or valproate, and the AMP-activated kinase (AMPK)-sirtuin 1 pathway activator, resveratrol. In this study, we demonstrated that the combination of valproate and resveratrol can restore the normal acetylation state of RelA in the SOD1(G93A) murine model of ALS, in order to obtain the neuroprotective form of NF-kB. We also investigated the sexually dimorphic development of the disease, as well as the sex-sensibility to the treatment administered. We showed that the combined drugs, which rescued AMPK activation, RelA and the histone 3 acetylation state, reduced the motor deficit and the disease pathology associated with motor neuron loss and microglial reactivity, Brain-Derived Neurotrophic Factor (BDNF) and B-cell lymphoma-extra large (Bcl-xL) level decline. Specifically, vehicle-administered males showed earlier onset and slower progression of the disease when compared to females. The treatment, administered at 50 days of life, postponed the time of onset in the male by 22 days, but not in a significant way in females. Nevertheless, in females, the drugs significantly reduced symptom severity of the later phase of the disease and prolonged the mice’s survival. Only minor beneficial effects were produced in the latter stage in males. Overall, this study shows a beneficial and sexually dimorphic response to valproate and resveratrol treatment in ALS mice.
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Jia J, Jin H, Nan D, Yu W, Huang Y. New insights into targeting mitochondria in ischemic injury. Apoptosis 2021; 26:163-183. [PMID: 33751318 DOI: 10.1007/s10495-021-01661-5] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/19/2021] [Indexed: 12/15/2022]
Abstract
Stroke is the leading cause of adult disability and death worldwide. Mitochondrial dysfunction has been recognized as a marker of neuronal death during ischemic stroke. Maintaining the function of mitochondria is important for improving the survival of neurons and maintaining neuronal function. Damaged mitochondria induce neuronal cell apoptosis by releasing reactive oxygen species (ROS) and pro-apoptotic factors. Mitochondrial fission and fusion processes and mitophagy are of great importance to mitochondrial quality control. This paper reviews the dynamic changes in mitochondria, the roles of mitochondria in different cell types, and related signaling pathways in ischemic stroke. This review describes in detail the role of mitochondria in the process of neuronal injury and protection in cerebral ischemia, and integrates neuroprotective drugs targeting mitochondria in recent years, which may provide a theoretical basis for the progress of treatment of ischemic stroke. The potential of mitochondrial-targeted therapy is also emphasized, which provides valuable insights for clinical research.
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Affiliation(s)
- Jingjing Jia
- Department of Neurology, Peking University First Hospital, No.8 Xishiku Street, Xicheng District, Beijing, 100034, China
| | - Haiqiang Jin
- Department of Neurology, Peking University First Hospital, No.8 Xishiku Street, Xicheng District, Beijing, 100034, China
| | - Ding Nan
- Department of Neurology, Peking University First Hospital, No.8 Xishiku Street, Xicheng District, Beijing, 100034, China
| | - Weiwei Yu
- Department of Neurology, Peking University First Hospital, No.8 Xishiku Street, Xicheng District, Beijing, 100034, China
| | - Yining Huang
- Department of Neurology, Peking University First Hospital, No.8 Xishiku Street, Xicheng District, Beijing, 100034, China.
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Small molecule induces mitochondrial fusion for neuroprotection via targeting CK2 without affecting its conventional kinase activity. Signal Transduct Target Ther 2021; 6:71. [PMID: 33602894 PMCID: PMC7893052 DOI: 10.1038/s41392-020-00447-6] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 11/23/2020] [Accepted: 11/24/2020] [Indexed: 01/31/2023] Open
Abstract
Mitochondrial fusion/fission dynamics plays a fundamental role in neuroprotection; however, there is still a severe lack of therapeutic targets for this biological process. Here, we found that the naturally derived small molecule echinacoside (ECH) significantly promotes mitochondrial fusion progression. ECH selectively binds to the previously uncharacterized casein kinase 2 (CK2) α' subunit (CK2α') as a direct cellular target, and genetic knockdown of CK2α' abolishes ECH-mediated mitochondrial fusion. Mechanistically, ECH allosterically regulates CK2α' conformation to recruit basic transcription factor 3 (BTF3) to form a binary protein complex. Then, the CK2α'/BTF3 complex facilitates β-catenin nuclear translocation to activate TCF/LEF transcription factors and stimulate transcription of the mitochondrial fusion gene Mfn2. Strikingly, in a mouse middle cerebral artery occlusion (MCAO) model, ECH administration was found to significantly improve cerebral injuries and behavioral deficits by enhancing Mfn2 expression in wild-type but not CK2α'+/- mice. Taken together, our findings reveal, for the first time, that CK2 is essential for promoting mitochondrial fusion in a Wnt/β-catenin-dependent manner and suggest that pharmacologically targeting CK2 is a promising therapeutic strategy for ischemic stroke.
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Liu YC, Hsu WL, Ma YL, Lee EHY. Melatonin Induction of APP Intracellular Domain 50 SUMOylation Alleviates AD through Enhanced Transcriptional Activation and Aβ Degradation. Mol Ther 2020; 29:376-395. [PMID: 32950104 PMCID: PMC7791018 DOI: 10.1016/j.ymthe.2020.09.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2020] [Revised: 07/06/2020] [Accepted: 09/01/2020] [Indexed: 12/18/2022] Open
Abstract
The amyloid precursor protein (APP) intracellular domain (AICD) is implicated in the pathogenesis of Alzheimer’s disease (AD), but post-translational modification of AICD has rarely been studied and its role in AD is unknown. In this study, we examined the role and molecular mechanism of AICD SUMOylation in the pathogenesis of AD. We found that AICD is SUMO-modified by the SUMO E3 ligase protein inhibitor of activated STAT1 (PIAS1) in the hippocampus at Lys-43 predominantly, and that knockdown of PIAS1 decreases endogenous AICD SUMOylation. AICD SUMOylation increases AICD association with its binding protein Fe65 and increases AICD nuclear translocation. Furthermore, AICD SUMOylation increases AICD association with cyclic AMP-responsive element binding protein (CREB) and p65 and their DNA binding for transcriptional activation of neprilysin (NEP) and transthyretin (TTR), two major Aβ-degrading enzymes, respectively. Consequently, AICD SUMOylation decreases the Aβ level, Aβ oligomerization, and amyloid plaque deposits. It also rescues spatial memory deficits in APP/PS1 mice. Conversely, blockade of AICD SUMOylation at Lys-43 produces the opposite effects. Melatonin is identified as an endogenous stimulus that induces AICD SUMOylation. It also decreases the Aβ level and rescues reduction of PIAS1, NEP, and TTR expression in APP/PS1 mice. In this study, we demonstrate that AICD SUMOylation functions as a novel endogenous defense mechanism to combat AD.
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Affiliation(s)
- Yen-Chen Liu
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei 114, Taiwan; Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan
| | - Wei-Lun Hsu
- Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan
| | - Yun-Li Ma
- Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan
| | - Eminy H Y Lee
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei 114, Taiwan; Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan.
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Stillman J, Martin A, Miguez MJ, McDaniel HR, Konefal J, Woolger JM, Lewis JE. Relationship between brain-derived neurotrophic factor and immune function during dietary supplement treatment of elderly with Alzheimer's dementia. J Clin Transl Res 2020; 5:68-75. [PMID: 32377581 PMCID: PMC7197050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2019] [Revised: 11/27/2019] [Accepted: 12/01/2019] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND AND AIM The objective of the present study was to investigate the relationships among pro-brain-derived neurotrophic factor (BDNF) and mature BDNF and immune functioning during aloe polymannose multinutrient complex (APMC) treatment in persons with moderate to severe Alzheimer's dementia (AD). MATERIALS AND METHODS An open-label trial of 12 months was used to execute the study. Thirty-four adults with AD were enrolled and consumed four teaspoons/day of APMC for 12 months. Subjects were assessed at baseline and 12 months follow-up for proBDNF and BDNF and cytokines, growth factors, T-cell and B-cell subsets, and complete blood count to measure immune functioning. All biomarkers were intercorrelated. RESULTS Several relationships were identified between proBDNF, BDNF, and BDNF/proBDNF ratio and immune function at 12 months, particularly BDNF with vascular endothelial growth factor (VEGF) (r=0.55, P=0.03), epidermal growth factor (EGF) (r=0.74, P=0.001), and CD95+CD3+ (%) (r=-0.64, P=0.03) and proBDNF with VEGF (r=0.64, P=0.02), EGF (r=0.86, P<0.001), and CD16+56+ (%) (r=-0.78, P<0.01). Other correlations were noted for various immune function variables with BDNF, proBDNF, and/or BDNF/proBDNF ratio at baseline and 12 months. Dichotomizing subjects on BDNF above and below 5000 pg/mL revealed additional relationships with platelets and neutrophils. CONCLUSIONS The associations between BDNF and proBDNF and various immune markers, such as VEGF, EGF, and CD95+CD3+ ratio, provide insight into the link between neurological function and the immune system. These relationships were even stronger in response to APMC treatment, which lends support to previous findings showing improved immune function after dietary supplementation. RELEVANCE FOR PATIENTS AD patients have conventional treatment options with limited efficacy for counteracting the deleterious effects of the disease on neurological function. The link between neurological and immune function has been understudied in this population. Overall, our results showed a significant beneficial relationship between immune and neurological function, particularly in response to 12 months of treatment with an all-natural polysaccharide-based dietary supplement that is a known immunomodulator. Thus, the use of this dietary supplement may benefit these patients by simultaneously improving immune and neurological function.
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Affiliation(s)
- Jordan Stillman
- 1Department of Psychiatry and Behavioral Sciences, Miami, Florida
| | - Alicia Martin
- 1Department of Psychiatry and Behavioral Sciences, Miami, Florida
| | - Maria-Jose Miguez
- 2Department of School of Integrated Science and Humanity, Florida International University, Miami, Florida
| | - H. Reginald McDaniel
- 3Department of Fisher Institute for Medical Research, Grand Prairie, Texas, United States
| | - Janet Konefal
- 4Department of Family Medicine and Community Health, Miami, Florida
| | - Judi M. Woolger
- 5Department of Medicine, University of Miami Miller School of Medicine, Miami, Florida
| | - John E. Lewis
- 1Department of Psychiatry and Behavioral Sciences, Miami, Florida,Corresponding author: John E. Lewis Department of Psychiatry and Behavioral Sciences, University of Miami Miller School of Medicine, 1120 NW 14th Street, Suite #1482A (D28), Miami, Florida 33136, United States. Phone: +1 305-243-6227.
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13
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Tao CC, Cheng KM, Ma YL, Hsu WL, Chen YC, Fuh JL, Lee WJ, Chao CC, Lee EHY. Galectin-3 promotes Aβ oligomerization and Aβ toxicity in a mouse model of Alzheimer's disease. Cell Death Differ 2019; 27:192-209. [PMID: 31127200 PMCID: PMC7206130 DOI: 10.1038/s41418-019-0348-z] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Revised: 04/13/2019] [Accepted: 05/02/2019] [Indexed: 12/23/2022] Open
Abstract
Amyloid-β (Aβ) oligomers largely initiate the cascade underlying the pathology of Alzheimer's disease (AD). Galectin-3 (Gal-3), which is a member of the galectin protein family, promotes inflammatory responses and enhances the homotypic aggregation of cancer cells. Here, we examined the role and action mechanism of Gal-3 in Aβ oligomerization and Aβ toxicities. Wild-type (WT) and Gal-3-knockout (KO) mice, APP/PS1;WT mice, APP/PS1;Gal-3+/- mice and brain tissues from normal subjects and AD patients were used. We found that Aβ oligomerization is reduced in Gal-3 KO mice injected with Aβ, whereas overexpression of Gal-3 enhances Aβ oligomerization in the hippocampi of Aβ-injected mice. Gal-3 expression shows an age-dependent increase that parallels endogenous Aβ oligomerization in APP/PS1 mice. Moreover, Aβ oligomerization, Iba1 expression, GFAP expression and amyloid plaque accumulation are reduced in APP/PS1;Gal-3+/- mice compared with APP/PS1;WT mice. APP/PS1;Gal-3+/- mice also show better acquisition and retention performance compared to APP/PS1;WT mice. In studying the mechanism underlying Gal-3-promoted Aβ oligomerization, we found that Gal-3 primarily co-localizes with Iba1, and that microglia-secreted Gal-3 directly interacts with Aβ. Gal-3 also interacts with triggering receptor expressed on myeloid cells-2, which then mediates the ability of Gal-3 to activate microglia for further Gal-3 expression. Immunohistochemical analyses show that the distribution of Gal-3 overlaps with that of endogenous Aβ in APP/PS1 mice and partially overlaps with that of amyloid plaque. Moreover, the expression of the Aβ-degrading enzyme, neprilysin, is increased in Gal-3 KO mice and this is associated with enhanced integrin-mediated signaling. Consistently, Gal-3 expression is also increased in the frontal lobe of AD patients, in parallel with Aβ oligomerization. Because Gal-3 expression is dramatically increased as early as 3 months of age in APP/PS1 mice and anti-Aβ oligomerization is believed to protect against Aβ toxicity, Gal-3 could be considered a novel therapeutic target in efforts to combat AD.
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Affiliation(s)
- Chih-Chieh Tao
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan.,Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan
| | - Kuang-Min Cheng
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan.,Institute of Neuroscience, National Cheng-chi University, Taipei, Taiwan
| | - Yun-Li Ma
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Wei-Lun Hsu
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Yan-Chu Chen
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan.,Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan
| | - Jong-Ling Fuh
- Faculty of Medicine, National Yang-Ming University School of Medicine, Taipei, Taiwan.,Department of Neurology, Neurological Institute, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Wei-Ju Lee
- Faculty of Medicine, National Yang-Ming University School of Medicine, Taipei, Taiwan.,Neurological Institute, Taichung Veterans General Hospital, Taichung, Taiwan.,Institute of Clinical Medicine, National Yang-Ming University School of Medicine, Taipei, Taiwan
| | - Chih-Chang Chao
- Institute of Neuroscience, National Cheng-chi University, Taipei, Taiwan
| | - Eminy H Y Lee
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan. .,Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan. .,Institute of Neuroscience, National Cheng-chi University, Taipei, Taiwan.
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14
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Liu SY, Ma YL, Hsu WL, Chiou HY, Lee EHY. Protein inhibitor of activated STAT1 Ser 503 phosphorylation-mediated Elk-1 SUMOylation promotes neuronal survival in APP/PS1 mice. Br J Pharmacol 2019; 176:1793-1810. [PMID: 30849179 DOI: 10.1111/bph.14656] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Revised: 01/29/2019] [Accepted: 02/10/2019] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND AND PURPOSE Protein inhibitor of activated STAT1 (PIAS1) is phosphorylated by IKKα at Ser90 in a PIAS1 E3 ligase activity-dependent manner. Whether PIAS1 is also phosphorylated at other residues and the functional significance of these additional phosphorylation events are not known. The transcription factor Elk-1 remains SUMOylated under basal conditions, but the role of Elk-1 SUMOylation in brain is unknown. Here, we examined the functional significance of PIAS1-mediated Elk-1 SUMOylation in Alzheimer's disease (AD) using the APP/PS1 mouse model of AD and amyloid β (Aβ) microinjections in vivo. EXPERIMENTAL APPROACH Novel phosphorylation site(s) on PIAS1 were identified by LC-MS/MS, and MAPK/ERK-mediated phosphorylation of Elk-1 demonstrated using in vitro kinase assays. Elk-1 SUMOylation by PIAS1 in brain was determined using in vitro SUMOylation assays. Apoptosis in hippocampus was assessed by measuring GADD45α expression by western blotting, and apoptosis of hippocampal neurons in APP/PS1 mice was assessed by TUNEL assay. KEY RESULTS Using LC-MS/MS, we identified a novel MAPK/ERK-mediated phosphorylation site on PIAS1 at Ser503 and showed this phosphorylation determines PIAS1 E3 ligase activity. In rat brain, Elk-1 was SUMOylated by PIAS1, which decreased Elk-1 phosphorylation and down-regulated GADD45α expression. Moreover, lentiviral-mediated transduction of Elk-1-SUMO1 reduced the number of hippocampal apoptotic neurons in APP/PS1 mice. CONCLUSIONS AND IMPLICATIONS MAPK/ERK-mediated phosphorylation of PIAS1 at Ser503 determines PIAS1 E3 ligase activity. Moreover, PIAS1 mediates SUMOylation of Elk-1, which functions as an endogenous defence mechanism against Aβ toxicity in vivo. Targeting Elk-1 SUMOylation could be considered a novel therapeutic strategy against AD.
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Affiliation(s)
- Shau-Yu Liu
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Yun-Li Ma
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Wei-Lun Hsu
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Hsin-Ying Chiou
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan.,Division of Endocrinology and Metabolism, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - Eminy H Y Lee
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
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15
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Fang W, Liao W, Zheng Y, Huang X, Weng X, Fan S, Chen X, Zhang X, Chen J, Xiao S, Thea A, Luan P, Liu J. Neurotropin reduces memory impairment and neuroinflammation via BDNF/NF-κB in a transgenic mouse model of Alzheimer's disease. Am J Transl Res 2019; 11:1541-1554. [PMID: 30972181 PMCID: PMC6456545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Accepted: 12/28/2018] [Indexed: 06/09/2023]
Abstract
Alzheimer's disease (AD) is a devastating neurodegenerative disease with limited treatments and no cure. Neurotropin (NTP) is an analgesic drug widely prescribed for neuropathic pain. Increasing evidence suggests that NTP may also protect against neurodegeneration, but NTP's treatment potential against memory impairments of AD remains to be explored. APP/PS1 mice, which model AD, were given NTP for three months then cognitively tested with the Morris water maze. Their Aβ burden, microglial and astrocytic activation, and BDNF levels were compared to untreated controls using immunofluorescent staining. Expression of pro-inflammatory cytokines (IL-1β, IL-6 and TNF-α) and NF-κB pathway related proteins (p65 and IκB-α) were examined by ELISA or Western blots in vivo and in vitro in the microglia cell line. Lastly, BV-2 cells were pre-treated with the selective BDNF inhibitor ANA-12 and with NTP to examine mechanistic pathways. Taken together, NTP treatment reduced cognitive impairment, Aβ deposits, and glial activation in cortex and hippocampus APP/PS1 mice. IL-1β, IL-6 and TNF-α also decreased after NTP treatment in vivo and in vitro, and BDNF levels rose. Also, NTP reduced p65 and IκB-α activation and the effect of NTP on pro-inflammatory cytokines and NF-κB pathway related proteins was abolished by BDNF inhibitor. Our results indicate that NTP reduces neuroinflammation and improves the cognitive deficits in APP/PS1 mice possibly via BDNF/NF-κB pathway. NTP may be a new promising drug candidate for patients with AD.
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Affiliation(s)
- Wenli Fang
- Department of Neurology, Sun Yat-sen Memorial Hospital, Sun Yat-sen UniversityGuangzhou 510120, Guangdong, China
| | - Wang Liao
- Department of Neurology, Sun Yat-sen Memorial Hospital, Sun Yat-sen UniversityGuangzhou 510120, Guangdong, China
- Department of Psychiatry, McLean Hospital, Harvard Medical SchoolBelmont, MA 02478, USA
| | - Yuqiu Zheng
- Department of Neurology, Sun Yat-sen Memorial Hospital, Sun Yat-sen UniversityGuangzhou 510120, Guangdong, China
| | - Xiaoyun Huang
- Department of Neurology, The Affiliated Houjie Hospital, Guangdong Medical UniversityDongguan 523945, Guangdong, China
| | - Xueling Weng
- Sun Yat-sen Memorial Hospital, Sun Yat-sen UniversityGuangzhou 510120, Guangdong, China
| | - Shengnuo Fan
- Department of Neurology, Sun Yat-sen Memorial Hospital, Sun Yat-sen UniversityGuangzhou 510120, Guangdong, China
| | - Xiaoyu Chen
- Department of Neurology, Sun Yat-sen Memorial Hospital, Sun Yat-sen UniversityGuangzhou 510120, Guangdong, China
- People’s Hospital of Zhongshan CityZhongshan 528403, Guangdong, China
| | - Xingmei Zhang
- Department of Clinical Neuroscience, Karolinska Institutet, Center for Molecular Medicine, Karolinska University HospitalKarolinska Sjukhuset, Sweden
| | - Jianjun Chen
- Department of Psychiatry, McLean Hospital, Harvard Medical SchoolBelmont, MA 02478, USA
| | - Songhua Xiao
- Department of Neurology, Sun Yat-sen Memorial Hospital, Sun Yat-sen UniversityGuangzhou 510120, Guangdong, China
| | - Anderson Thea
- Department of Psychiatry, McLean Hospital, Harvard Medical SchoolBelmont, MA 02478, USA
| | - Ping Luan
- Medicine School, Shenzhen UniversityShenzhen 518060, Guangdong, China
| | - Jun Liu
- Department of Neurology, Sun Yat-sen Memorial Hospital, Sun Yat-sen UniversityGuangzhou 510120, Guangdong, China
- Laboratory of RNA and Major Diseases of Brain and Heart, Sun Yat-sen Memorial Hospital, Sun Yat-sen UniversityGuangzhou 510120, Guangdong, China
- Guangdong Province Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen UniversityGuangzhou 510120, Guangdong, China
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16
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Schiaffino L, Bonafede R, Scambi I, Parrella E, Pizzi M, Mariotti R. Acetylation state of RelA modulated by epigenetic drugs prolongs survival and induces a neuroprotective effect on ALS murine model. Sci Rep 2018; 8:12875. [PMID: 30150770 PMCID: PMC6110772 DOI: 10.1038/s41598-018-30659-4] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Accepted: 07/24/2018] [Indexed: 12/13/2022] Open
Abstract
Dysregulation in acetylation homeostasis has been implicated in the pathogenesis of the amyotrophic lateral sclerosis (ALS), a fatal neurodegenerative disorder. It is known that the acetylation of transcriptional factors regulates their activity. The acetylation state of NF-kB RelA has been found to dictate the neuroprotective versus the neurotoxic effect of p50/RelA. Here we showed that the pro-apoptotic acetylation mode of RelA, involving a general lysine deacetylation of the subunit with the exclusion of the lysine 310, is evident in the lumbar spinal cord of SOD1(G93A) mice, a murine model of ALS. The administration of the HDAC inhibitor MS-275 and the AMPK/sirtuin 1 activator resveratrol restored the normal RelA acetylation in SOD1(G93A) mice. The SOD1(G93A) mice displayed a 3 weeks delay of the disease onset, associated with improvement of motor performance, and 2 weeks increase of lifespan. The epigenetic treatment rescued the lumbar motor neurons affected in SOD1(G93A) mice, accompanied by increased levels of protein products of NF-kB-target genes, Bcl-xL and brain-derived neurotrophic factor. In conclusion, we here demonstrate that MS-275 and resveratrol restore the acetylation state of RelA in the spinal cord, delaying the onset and increasing the lifespan of SOD1(G93A) mice.
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Affiliation(s)
- Lorenzo Schiaffino
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Roberta Bonafede
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Ilaria Scambi
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Edoardo Parrella
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Marina Pizzi
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Raffaella Mariotti
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy.
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17
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Neuroprotection by aripiprazole against β-amyloid-induced toxicity by P-CK2α activation via inhibition of GSK-3β. Oncotarget 2017; 8:110380-110391. [PMID: 29299155 PMCID: PMC5746390 DOI: 10.18632/oncotarget.22777] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2017] [Accepted: 11/19/2017] [Indexed: 12/12/2022] Open
Abstract
Psychosis is reported over 30% of patients with Alzheimer's disease (AD) in clinics. Aripiprazole is an atypical antipsychotic drug with partial agonist activity at the D2 dopamine and 5-HT1A receptors with low side-effect profile. We identified aripiprazole is able to overcome the amyloid-β (Aβ)-evoked neurotoxicity and then increase the cell viability. This study elucidated the mechanism(s) by which aripiprazole ameliorates Aβ1-42-induced decreased neurite outgrowth and viability in neuronal cells. Pretreatment with aripiprazole increased Brain-derived neurotrophic factor (BDNF) mRNA and protein expressions in N2a cells. Additionally, phosphorylated casein kinase 2α at Y 255 (P-CK2α) was increased in time- and concentration-dependent manners. Furthermore, Aβ1-42-induced decreased BDNF and P-CK2α expression were increased over control level by aripiprazole. Subsequently, Aβ1-42-induced decreased levels of phosphorylated glycogen synthase-3β at Ser9 (P-GSK-3β) and nuclear P-β-catenin (Ser675) were elevated by aripiprazole, which were inhibited by K252A (inhibitor of BDNF receptor) and tetrabromocinnamic acid (TBCA, CK2 inhibitor), indicating that BDNF and P-CK2α activation are implicated in the aripiprazole effects. Expressions of cyclin D1 and insulin-like growth factor 2 (IGF2) mRNA were increased by aripiprazole; even in the presence of Aβ1-42, which was blocked by K252A and TBCA. In CK2α gene-silenced N2a cells, aripiprazole failed to increase P-GSK-3β and P-β-catenin expressions. Consequently, aripiprazole ameliorated Aβ1-42-induced attenuation of neurite elongation in HT22 cells, and this effect was blocked by both TBCA and imatinib. Decreased viability induced by Aβ1-42 was recovered by aripiprazole. These findings provide evidence supporting that aripiprazole can provide an effective therapeutic strategy against Aβ-induced neurotoxicity in AD-associated psychosis.
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18
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Hsu WL, Ma YL, Liu YC, Lee EHY. Smad4 SUMOylation is essential for memory formation through upregulation of the skeletal myopathy gene TPM2. BMC Biol 2017; 15:112. [PMID: 29183317 PMCID: PMC5706330 DOI: 10.1186/s12915-017-0452-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2017] [Accepted: 11/07/2017] [Indexed: 11/22/2022] Open
Abstract
Background Smad4 is a critical effector of TGF-β signaling that regulates a variety of cellular functions. However, its role in the brain has rarely been studied. Here, we examined the molecular mechanisms underlying the post-translational regulation of Smad4 function by SUMOylation, and its role in spatial memory formation. Results In the hippocampus, Smad4 is SUMOylated by the E3 ligase PIAS1 at Lys-113 and Lys-159. Both spatial training and NMDA injection enhanced Smad4 SUMOylation. Inhibition of Smad4 SUMOylation impaired spatial learning and memory in rats by downregulating TPM2, a gene associated with skeletal myopathies. Similarly, knockdown of TPM2 expression impaired spatial learning and memory, while TPM2 mRNA and protein expression increased after spatial training. Among the TPM2 mutations associated with skeletal myopathies, the TPM2E122K mutation was found to reduce TPM2 expression and impair spatial learning and memory in rats. Conclusions We have identified a novel role of Smad4 SUMOylation and TPM2 in learning and memory formation. These results suggest that patients with skeletal myopathies who carry the TPM2E122K mutation may also have deficits in learning and memory functions. Electronic supplementary material The online version of this article (doi:10.1186/s12915-017-0452-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Wei L Hsu
- Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan
| | - Yun L Ma
- Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan
| | - Yen C Liu
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei 114, Taiwan
| | - Eminy H Y Lee
- Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan. .,Graduate Institute of Life Sciences, National Defense Medical Center, Taipei 114, Taiwan.
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19
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Chen YC, Ma YL, Lin CH, Cheng SJ, Hsu WL, Lee EHY. Galectin-3 Negatively Regulates Hippocampus-Dependent Memory Formation through Inhibition of Integrin Signaling and Galectin-3 Phosphorylation. Front Mol Neurosci 2017; 10:217. [PMID: 28744198 PMCID: PMC5504160 DOI: 10.3389/fnmol.2017.00217] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2017] [Accepted: 06/20/2017] [Indexed: 01/06/2023] Open
Abstract
Galectin-3, a member of the galectin protein family, has been found to regulate cell proliferation, inhibit apoptosis and promote inflammatory responses. Galectin-3 is also expressed in the adult rat hippocampus, but its role in learning and memory function is not known. Here, we found that contextual fear-conditioning training, spatial training or injection of NMDA into the rat CA1 area each dramatically decreased the level of endogenous galectin-3 expression. Overexpression of galectin-3 impaired fear memory, whereas galectin-3 knockout (KO) enhanced fear retention, spatial memory and hippocampal long-term potentiation. Galectin-3 was further found to associate with integrin α3, an association that was decreased after fear-conditioning training. Transfection of the rat CA1 area with small interfering RNA against galectin-3 facilitated fear memory and increased phosphorylated focal adhesion kinase (FAK) levels, effects that were blocked by co-transfection of the FAK phosphorylation-defective mutant Flag-FAKY397F. Notably, levels of serine-phosphorylated galectin-3 were decreased by fear conditioning training. In addition, blockade of galectin-3 phosphorylation at Ser-6 facilitated fear memory, whereas constitutive activation of galectin-3 at Ser-6 impaired fear memory. Interestingly galectin-1 plays a role in fear-memory formation similar to that of galectin-3. Collectively, our data provide the first demonstration that galectin-3 is a novel negative regulator of memory formation that exerts its effects through both extracellular and intracellular mechanisms.
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Affiliation(s)
- Yan-Chu Chen
- Graduate Institute of Life Sciences, National Defense Medical CenterTaipei, Taiwan
| | - Yun-Li Ma
- Institute of Biomedical Sciences, Academia SinicaTaipei, Taiwan
| | | | - Sin-Jhong Cheng
- Institute of Biomedical Sciences, Academia SinicaTaipei, Taiwan.,Neuroscience Program in Academia SinicaTaipei, Taiwan
| | - Wei-Lun Hsu
- Institute of Biomedical Sciences, Academia SinicaTaipei, Taiwan
| | - Eminy H-Y Lee
- Graduate Institute of Life Sciences, National Defense Medical CenterTaipei, Taiwan.,Institute of Biomedical Sciences, Academia SinicaTaipei, Taiwan
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20
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Dygalo NN, Bannova AV, Sukhareva EV, Shishkina GT, Ayriyants KA, Kalinina TS. Effects of short-term exposure to lithium on antiapoptotic Bcl-xL protein expression in cortex and hippocampus of rats after acute stress. BIOCHEMISTRY (MOSCOW) 2017; 82:345-350. [DOI: 10.1134/s0006297917030130] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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21
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Tao CC, Hsu WL, Ma YL, Cheng SJ, Lee EH. Epigenetic regulation of HDAC1 SUMOylation as an endogenous neuroprotection against Aβ toxicity in a mouse model of Alzheimer's disease. Cell Death Differ 2017; 24:597-614. [PMID: 28186506 PMCID: PMC5384022 DOI: 10.1038/cdd.2016.161] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Revised: 12/04/2016] [Accepted: 12/13/2016] [Indexed: 01/08/2023] Open
Abstract
Amyloid-β (Aβ) produces neurotoxicity in the brain and causes neuronal death, but the endogenous defense mechanism that is activated on Aβ insult is less well known. Here we found that acute Aβ increases the expression of PIAS1 and Mcl-1 via activation of MAPK/ERK, and Aβ induction of PIAS1 enhances HDAC1 SUMOylation in rat hippocampus. Knockdown of PIAS1 decreases endogenous HDAC1 SUMOylation and blocks Aβ induction of Mcl-1. Sumoylated HDAC1 reduces it association with CREB, increases CREB binding to the Mcl-1 promoter and mediates Aβ induction of Mcl-1 expression. Transduction of SUMO-modified lenti-HDAC1 vector to the hippocampus of APP/PS1 mice rescues spatial learning and memory deficit and long-term potentiation impairment in APP/PS1 mice. It also reduces the amount of amyloid plaque and the number of apoptotic cells in CA1 area of APP/PS1 mice. Meanwhile, HDAC1 SUMOylation decreases HDAC1 binding to the neprilysin promoter. These results together reveal an important role of HDAC1 SUMOylation as a naturally occurring defense mechanism protecting against Aβ toxicity and provide an alternative therapeutic strategy against AD.
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Affiliation(s)
- Chih Chieh Tao
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan
| | - Wei Lun Hsu
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Yun Li Ma
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Sin Jhong Cheng
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan.,Neuroscience Program in Academia Sinica, Taipei, Taiwan
| | - Eminy Hy Lee
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan.,Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
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22
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Wehner AB, Milen AM, Albin RL, Pierchala BA. The p75 neurotrophin receptor augments survival signaling in the striatum of pre-symptomatic Q175(WT/HD) mice. Neuroscience 2016; 324:297-306. [PMID: 26947127 PMCID: PMC4849895 DOI: 10.1016/j.neuroscience.2016.02.069] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Revised: 02/26/2016] [Accepted: 02/28/2016] [Indexed: 12/19/2022]
Abstract
Huntington's disease (HD) is a dominantly inherited neurodegenerative disorder characterized by a constellation of motor, cognitive, and psychiatric features. Striatal medium spiny neurons, one of the most affected populations, are dependent on brain-derived neurotrophic factor (BDNF) anterogradely transported from the cortex for proper function and survival. Recent studies suggest both receptors for BDNF, TrkB and p75 neurotrophin receptor (p75), are improperly regulated in the striata of HD patients and mouse models of HD. While BDNF-TrkB signaling almost exclusively promotes survival and metabolic function, p75 signaling is able to induce survival or apoptosis depending on the available ligand and associated co-receptor. We investigated the role of p75 in the Q175 knock-in mouse model of HD by examining the levels and activation of downstream signaling molecules, and subsequently examining Hdh(+/Q175);p75(-/-) mice to determine if p75 represents a promising therapeutic target. In Hdh(+/Q175);p75(+/+) mice, we observed enhanced survival signaling as evidenced by an increase in phosphorylation and activation of Akt and the p65 subunit of NFκB in the striatum at 5 months of age and an increase in XIAP expression compared to Hdh(+/+);p75(+/+) mice; this increase was lost in Hdh(+/Q175);p75(-/-) mice. Hdh(+/Q175);p75(-/-) mice also showed a decrease in Bcl-XL expression by immunoblotting compared to Hdh(+/Q175);p75(+/+) and Hdh(+/+);p75(+/+) littermates. Consistent with diminished survival signaling, DARPP-32 expression decreased both by immunoblotting and by immunohistochemistry in Hdh(+/Q175);p75(-/-) mice compared to Hdh(+/+);p75(+/+), Hdh(+/Q175);p75(+/+), and Hdh(+/+);p75(-/-) littermates. Additionally, striatal volume declined to a greater extent in Hdh(+/Q175);p75(-/-) when compared to Hdh(+/Q175);p75(+/+) littermates at 12 months, indicating a more aggressive onset of degeneration. These data suggest that p75 signaling plays an early role in augmenting pro-survival signaling in the striatum and that disruption of p75 signaling at a pre-symptomatic age may exacerbate pathologic changes in Hdh(+/Q175) mice.
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Affiliation(s)
- A B Wehner
- Department of Biologic and Materials Sciences, University of Michigan School of Dentistry, Ann Arbor, MI, USA; Neuroscience Graduate Program, University of Michigan School of Medicine, Ann Arbor, MI, USA
| | - A M Milen
- Department of Biologic and Materials Sciences, University of Michigan School of Dentistry, Ann Arbor, MI, USA
| | - R L Albin
- Neuroscience Graduate Program, University of Michigan School of Medicine, Ann Arbor, MI, USA; Department of Neurology, University of Michigan School of Medicine, Ann Arbor, MI, USA
| | - B A Pierchala
- Department of Biologic and Materials Sciences, University of Michigan School of Dentistry, Ann Arbor, MI, USA; Neuroscience Graduate Program, University of Michigan School of Medicine, Ann Arbor, MI, USA.
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Simon L, Song K, Vande Stouwe C, Hollenbach A, Amedee A, Mohan M, Winsauer P, Molina P. Δ9-Tetrahydrocannabinol (Δ9-THC) Promotes Neuroimmune-Modulatory MicroRNA Profile in Striatum of Simian Immunodeficiency Virus (SIV)-Infected Macaques. J Neuroimmune Pharmacol 2016; 11:192-213. [PMID: 26607731 PMCID: PMC4773048 DOI: 10.1007/s11481-015-9645-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Accepted: 11/12/2015] [Indexed: 12/22/2022]
Abstract
Cannabinoid administration before and after simian immunodeficiency virus (SIV)-inoculation ameliorated disease progression and decreased inflammation in male rhesus macaques. Δ9-tetrahydrocannabinol (Δ9-THC) did not increase viral load in brain tissue or produce additive neuropsychological impairment in SIV-infected macaques. To determine if the neuroimmunomodulation of Δ9-THC involved differential microRNA (miR) expression, miR expression in the striatum of uninfected macaques receiving vehicle (VEH) or Δ9-THC (THC) and SIV-infected macaques administered either vehicle (VEH/SIV) or Δ9-THC (THC/SIV) was profiled using next generation deep sequencing. Among the 24 miRs that were differentially expressed among the four groups, 16 miRs were modulated by THC in the presence of SIV. These 16 miRs were classified into four categories and the biological processes enriched by the target genes determined. Our results indicate that Δ9-THC modulates miRs that regulate mRNAs of proteins involved in 1) neurotrophin signaling, 2) MAPK signaling, and 3) cell cycle and immune response thus promoting an overall neuroprotective environment in the striatum of SIV-infected macaques. This is also reflected by increased Brain Derived Neurotrophic Factor (BDNF) and decreased proinflammatory cytokine expression compared to the VEH/SIV group. Whether Δ9-THC-mediated modulation of epigenetic mechanisms provides neuroprotection in other regions of the brain and during chronic SIV-infection remains to be determined.
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Affiliation(s)
- Liz Simon
- Department of Physiology, Alcohol and Drug Abuse Center of Excellence, Louisiana State University Health Sciences, 1901 Perdido Street, Medical Education Building 7205, P7-3, New Orleans, LA, 70112, USA
| | - Keijing Song
- Department of Physiology, Louisiana State University Health Sciences Center, 1901 Perdido Street, New Orleans, LA, 70112, USA
| | - Curtis Vande Stouwe
- Department of Physiology, Louisiana State University Health Sciences Center, 1901 Perdido Street, New Orleans, LA, 70112, USA
| | - Andrew Hollenbach
- Department of Genetics, Louisiana State University Health Sciences Center, 1901 Perdido Street, New Orleans, LA, 70112, USA
| | - Angela Amedee
- Department of Microbiology, Immunology, & Parasitology; Alcohol and Drug Abuse Center of Excellence, Louisiana State University Health Sciences Center, 1901 Perdido Street, New Orleans, LA, 70112, USA
| | - Mahesh Mohan
- Department of Comparative Pathology, Tulane National Primate Research Center, 18703 3 Rivers Rd, Covington, LA, 70433, USA
| | - Peter Winsauer
- Department of Pharmacology; Alcohol and Drug Abuse Center of Excellence, Louisiana State University Health Sciences Center, 1901 Perdido Street, New Orleans, LA, 70112, USA
| | - Patricia Molina
- Department of Physiology, Alcohol and Drug Abuse Center of Excellence, Louisiana State University Health Sciences, 1901 Perdido Street, Medical Education Building 7205, P7-3, New Orleans, LA, 70112, USA.
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Tai DJC, Liu YC, Hsu WL, Ma YL, Cheng SJ, Liu SY, Lee EHY. MeCP2 SUMOylation rescues Mecp2-mutant-induced behavioural deficits in a mouse model of Rett syndrome. Nat Commun 2016; 7:10552. [PMID: 26842955 PMCID: PMC4743023 DOI: 10.1038/ncomms10552] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Accepted: 12/24/2015] [Indexed: 11/17/2022] Open
Abstract
The methyl-CpG-binding protein 2 (MeCP2) gene, MECP2, is an X-linked gene encoding the MeCP2 protein, and mutations of MECP2 cause Rett syndrome (RTT). However, the molecular mechanism of MECP2-mutation-caused RTT is less known. Here we find that MeCP2 could be SUMO-modified by the E3 ligase PIAS1 at Lys-412. MeCP2 phosphorylation (at Ser-421 and Thr-308) facilitates MeCP2 SUMOylation, and MeCP2 SUMOylation is induced by NMDA, IGF-1 and CRF in the rat brain. MeCP2 SUMOylation releases CREB from the repressor complex and enhances Bdnf mRNA expression. Several MECP2 mutations identified in RTT patients show decreased MeCP2 SUMOylation. Re-expression of wild-type MeCP2 or SUMO-modified MeCP2 in Mecp2-null neurons rescues the deficits of social interaction, fear memory and LTP observed in Mecp2 conditional knockout (cKO) mice. These results together reveal an important role of MeCP2 SUMOylation in social interaction, memory and synaptic plasticity, and that abnormal MeCP2 SUMOylation is implicated in RTT. Post-translational modifications of methyl-CpG-binding protein 2 (MeCP2) are important for its function and dysfunction in Rett syndrome. Here, Tai et al. show a functional interaction between MeCP2 SUMOylation and phosphorylation in rodent behavior and synaptic plasticity.
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Affiliation(s)
- Derek J C Tai
- Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan
| | - Yen C Liu
- Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan.,Graduate Institute of Life Sciences, National Defense Medical Center, Taipei 114, Taiwan
| | - Wei L Hsu
- Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan
| | - Yun L Ma
- Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan
| | - Sin J Cheng
- Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan.,Neuroscience Program in Academia Sinica, Taipei 115, Taiwan
| | - Shau Y Liu
- Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan
| | - Eminy H Y Lee
- Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan
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25
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Tsybko AS, Il’chibaeva TV, Naumenko VS. The effects of the glial cell line-derived neurotrophic factor (GDNF) on the levels of mRNA of apoptotic genes Bax and Bcl-xl in the brain of mice genetically predisposed to pathological behavior. ACTA ACUST UNITED AC 2015. [DOI: 10.1134/s2079059715040152] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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26
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Wang Y, Schachner M. The intracellular domain of L1CAM binds to casein kinase 2α and is neuroprotective via inhibition of the tumor suppressors PTEN and p53. J Neurochem 2015; 133:828-43. [PMID: 25727698 DOI: 10.1111/jnc.13083] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Revised: 02/05/2015] [Accepted: 02/24/2015] [Indexed: 02/05/2023]
Abstract
Cell adhesion molecule L1 promotes neuritogenesis and neuronal survival through triggering MAPK pathways. Based on the findings that L1 is associated with casein kinase 2 (CK2), and that deficiency in PTEN promotes neuritogenesis in vitro and regeneration after trauma, we examined the functional relationship between L1 and PTEN. In parallel, we investigated the tumor suppressor p53, which also regulates neuritogenesis. Here, we report that the intracellular domain of L1 binds to the subunit CK2α, and that knockdown of L1 leads to CK2 dephosphorylation and an increase in PTEN and p53 levels. Overexpression of L1, but not the L1 mutants L1 (S1181N, E1184V), which reduced binding between L1 and CK2, reduced expression levels of PTEN and p53 proteins, and enhanced levels of phosphorylated CK2α and mammalian target of rapamycin, which is a downstream effector of PTEN and p53. Treatment of neurons with a CK2 inhibitor or transfection with CK2α siRNA increased levels of PTEN and p53, and inhibited neuritogenesis. The combined observations indicate that L1 downregulates expression of PTEN and p53 via direct binding to CK2α. We suggest that L1 stimulates neuritogenesis by activating CK2α leading to decreased levels of PTEN and p53 via a novel, L1-triggered and CK2α-mediated signal transduction pathway. L1CAM (L1 cell adhesion molecule) is implicated in neural functions through the cognate src/MAP kinase signaling pathway. We now describe a novel signaling platform operating via the alpha subunit of casein kinase 2 which binds to the intracellular domain of L1. Knockdown of L1CAM leads to increased levels of tumor suppressor PTEN (phosphatase and tensin homolog) and p53, known to inhibit neuritogenesis in vitro and recovery from trauma in vivo. By activating this enzyme, L1CAM adds to its beneficial functions by decreasing the levels of PTEN and p53.
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Affiliation(s)
- Yan Wang
- Center for Neuroscience, Shantou University Medical College, Shantou, Guangdong, China
| | - Melitta Schachner
- Center for Neuroscience, Shantou University Medical College, Shantou, Guangdong, China
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27
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Abstract
Humans and their predecessors evolved in environments where they were challenged intermittently with: 1) food scarcity; 2) the need for aerobic fitness to catch/kill prey and avoid or repel attackers; and 3) exposure to biological toxins present in foodstuffs. Accordingly, cells and organ systems acquired and retained molecular signaling and metabolic pathways through which the environmental challenges enhanced the functionality and resilience of the cells and organisms. Within the past 60 years there has been a precipitous diminution of such challenges in modern societies because of the development of technologies that provide a continuous supply of energy-dense processed foods and that largely eliminate the need for physical exertion. As a consequence of the modern 'couch potato' lifestyle, signaling pathways that mediate beneficial effects of environmental challenges on health and disease resistance are disengaged, thereby rendering people vulnerable to obesity, diabetes, cardiovascular disease, cancers and neurodegenerative disorders. Reversal of the epidemic of diseases caused by unchallenging lifestyles will require a society-wide effort to re-introduce intermittent fasting, exercise and consumption of plants containing hormetic phytochemicals into daily and weekly routines.
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Affiliation(s)
- Mark P Mattson
- Laboratory of Neurosciences, National Institute on Aging Intramural Research Program, Baltimore, MD. 21224
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28
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Chen YC, Hsu WL, Ma YL, Tai DJC, Lee EHY. CREB SUMOylation by the E3 ligase PIAS1 enhances spatial memory. J Neurosci 2014; 34:9574-89. [PMID: 25031400 PMCID: PMC6608321 DOI: 10.1523/jneurosci.4302-13.2014] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2013] [Revised: 05/25/2014] [Accepted: 06/02/2014] [Indexed: 11/21/2022] Open
Abstract
cAMP-responsive element binding protein (CREB) phosphorylation and signaling plays an important role in long-term memory formation, but other posttranslational modifications of CREB are less known. Here, we found that CREB1Δ, the short isoform of CREB, could be sumoylated by the small ubiquitin-like modifier (SUMO) E3 ligase protein inhibitor of activated STAT1 (PIAS1) at Lys271 and Lys290 and PIAS1 SUMOylation of CREB1Δ increased the expression level of CREB1Δ. CREB1Δ could also be sumoylated by other PIAS family proteins, but not by the E3 ligases RanBP2 and Pc2 or by the E2 ligase Ubc9. Furthermore, water maze training increased the level of endogenous CREB SUMOylation in rat CA1 neurons determined by in vitro SUMOylation assay, but this effect was not observed in other brain areas. Moreover, transduction of Lenti-CREBWT to rat CA1 area facilitated, whereas transduction of Lenti-CREB double sumo-mutant (CREBK271RK290R) impaired, spatial learning and memory performance. Transduction of Lenti-CREBWT-SUMO1 fusion vector to rat CA1 area showed a more significant effect in enhancing spatial learning and memory and CREB SUMOylation. Lenti-CREBWT transduction increased, whereas Lenti-CREBK271RK290R transduction decreased, CREB DNA binding to the brain-derived neurotrophic factor (bdnf) promoter and decreased bdnf mRNA expression. Knock-down of PIAS1 expression in CA1 area by PIAS1 siRNA transfection impaired spatial learning and memory and decreased endogenous CREB SUMOylation. In addition, CREB SUMOylation was CREB phosphorylation dependent and lasted longer. Therefore, CREB phosphorylation may be responsible for signal transduction during the early phase of long-term memory formation, whereas CREB SUMOylation sustains long-term memory.
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Affiliation(s)
- Yan-Chu Chen
- Graduate Institute of Life Sciences, National Defense Medical Center, and
| | - Wei-Lun Hsu
- Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan, Republic of China
| | - Yun-Li Ma
- Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan, Republic of China
| | - Derek J C Tai
- Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan, Republic of China
| | - Eminy H Y Lee
- Graduate Institute of Life Sciences, National Defense Medical Center, and Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan, Republic of China
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29
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STAT1 negatively regulates spatial memory formation and mediates the memory-impairing effect of Aβ. Neuropsychopharmacology 2014; 39:746-58. [PMID: 24081304 PMCID: PMC3895253 DOI: 10.1038/npp.2013.263] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Revised: 08/29/2013] [Accepted: 09/16/2013] [Indexed: 01/15/2023]
Abstract
Signal transducer and activator of transcription-1 (STAT1) has an important role in inflammation and the innate immune response, but its role in the central nervous system is less well understood. Here, we examined the role of STAT1 in spatial learning and memory, and assessed the involvement of STAT1 in mediating the memory-impairing effect of amyloid-beta (Aβ). We found that water maze training downregulated STAT1 expression in the rat hippocampal CA1 area, and spatial learning and memory function was enhanced in Stat1-knockout mice. Conversely, overexpression of STAT1 impaired water maze performance. STAT1 strongly upregulated the expression of the extracellular matrix protein laminin β1 (LB1), which also impaired water maze performance in rats. Furthermore, Aβ impaired spatial learning and memory in association with a dose-dependent increase in STAT1 and LB1 expression, but knockdown of STAT1 and LB1 both reversed this effect of Aβ. This Aβ-induced increase in STAT1 and LB1 expression was also associated with a decrease in the expression of the N-methyl-D-aspartate receptor (NMDAR) subunits, NR1, and NR2B. Overexpression of NR1 or NR2B or exogenous application of NMDA reversed Aβ-induced learning and memory deficits as well as Aβ-induced STAT1 and LB1 expression. Our results demonstrate that STAT1 negatively regulates spatial learning and memory through transcriptional regulation of LB1 expression. We also identified a novel mechanism for Aβ pathogenesis through STAT1 induction. Notably, impairment of spatial learning and memory by this STAT1-mediated mechanism is independent of cAMP responsive element-binding protein signaling.
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30
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Barbosa IG, Nogueira CRC, Rocha NP, Queiroz ALL, Vago JP, Tavares LP, Assis F, Fagundes CT, Huguet RB, Bauer ME, Teixeira AL, de Sousa LP. Altered intracellular signaling cascades in peripheral blood mononuclear cells from BD patients. J Psychiatr Res 2013; 47:1949-54. [PMID: 24075327 DOI: 10.1016/j.jpsychires.2013.08.019] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2013] [Revised: 08/23/2013] [Accepted: 08/26/2013] [Indexed: 01/17/2023]
Abstract
Bipolar disorder (BD) is a severe psychiatric disorder of complex physiopathology that has been associated with a pro-inflammatory state. The aim of the present study was to investigate intracellular pathways associated with inflammatory signaling, assessing the phosphorylation levels of transcription factor nuclear factor kappa B (NF-κB) and mitogen-activated protein kinase (MAPKs) in peripheral blood mononuclear cells of euthymic BD patients and healthy controls. Fifteen BD euthymic type I patients, and 12 healthy controls matched by age and gender were enrolled in this study. All subjects were assessed by the Mini-International Neuropsychiatry Interview and the patients also by the Young Mania Rating Scale and the Hamilton Depression Rating Scale. Phosphorylation levels of p65 NF-κB subunit, and MAPK ERK1/2, and p38 were assessed by Western blot and flow cytometry. Plasma cytokines (IL-2, IL-4, IL6, IL-10, IFN-γ, TNF-α, and IL-17A) were measured using cytometric bead arrays. Western blot and flow cytometry analyses showed increased phosphorylation levels of p65 NF-κB subunit, and MAPKs ERK1/2, and p38 in BD patients in euthymia in comparison with controls. BD patients presented increased pro-inflammatory cytokines levels in comparison with controls, and TNF-α correlated with the levels of phosphorylated p65 NF-κB. The present study found increased activation of MAPK and NF-κB pathways in BD patients, which is in line with a pro-inflammatory status.
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Affiliation(s)
- Izabela Guimarães Barbosa
- Programa de Pós Graduação em Neurociências, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil; Laboratório Interdisciplinar de Investigação Médica (LIIM), Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
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31
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Sun YY, Lin SH, Lin HC, Hung CC, Wang CY, Lin YC, Hung KS, Lien CC, Kuan CY, Lee YH. Cell type-specific dependency on the PI3K/Akt signaling pathway for the endogenous Epo and VEGF induction by baicalein in neurons versus astrocytes. PLoS One 2013; 8:e69019. [PMID: 23904909 PMCID: PMC3719842 DOI: 10.1371/journal.pone.0069019] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2013] [Accepted: 06/04/2013] [Indexed: 02/06/2023] Open
Abstract
The neuroprotective effect of baicalein is generally attributed to inhibition of
12/15-lipoxygenase (12/15-LOX) and suppression of oxidative stress, but recent
studies showed that baicalein also activates hypoxia-inducible factor-α (HIF1α)
through inhibition of prolyl hydrolase 2 (PHD2) and activation of the
phosphatidylinositide-3 kinase (PI3K)/Akt signaling pathway. Yet, the
significance and regulation of prosurvival cytokines erythropoietin (Epo) and
vascular endothelial growth factor (VEGF), two transcriptional targets of HIF1α,
in baicalein-mediated neuroprotection in neurons and astrocytes remains unknown.
Here we investigated the causal relationship between the PI3K/Akt signaling
pathway and Epo/VEGF expression in baicalein-mediated neuroprotection in primary
rat cortical neurons and astrocytes. Our results show that baicalein induced Epo
and VEGF expression in a HIF1α- and PI3K/Akt-dependent manner in neurons.
Baicalein also protected neurons against excitotoxicity in a PI3K- and
Epo/VEGF-dependent manner without affecting neuronal excitability. In contrast,
at least a 10-fold higher concentration of baicalein was needed to induce
Epo/VEGF production and PI3K/Akt activity in astrocytes for protection of
neurons. Moreover, only baicalein-induced astrocytic VEGF, but not Epo
expression requires HIF1α, while PI3K/Akt signaling had little role in
baicalein-induced astrocytic Epo/VEGF expression. These results suggest distinct
mechanisms of baicalein-mediated Epo/VEGF production in neurons and astrocytes
for neuroprotection, and provide new insights into the mechanisms and potential
of baicalein in treating brain injury in vivo.
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Affiliation(s)
- Yu-Yo Sun
- Division of Neurology, Department of Pediatrics, the Center for
Neurodegenerative Disease, Emory University School of Medicine, Atlanta,
Georgia, United States of America
| | - Shang-Hsuan Lin
- Department and Institute of Physiology, National Yang-Ming University,
Taipei, Taiwan
| | - Hung-Cheng Lin
- Graduate Institute of Medical Sciences, Taipei Medical University,
Taipei, Taiwan
| | - Chia-Chi Hung
- Graduate Institute of Medical Sciences, Taipei Medical University,
Taipei, Taiwan
| | - Chen-Yu Wang
- Department and Institute of Physiology, National Yang-Ming University,
Taipei, Taiwan
- Brain Research Center, National Yang-Ming University, Taipei,
Taiwan
| | - Yen-Chu Lin
- Institute of Neuroscience, National Yang-Ming University, Taipei,
Taiwan
| | - Kuo-Sheng Hung
- Department of Neurosurgery, Taipei Medical University Wan Fang Hospital,
Taipei, Taiwan
| | - Cheng-Chang Lien
- Brain Research Center, National Yang-Ming University, Taipei,
Taiwan
- Institute of Neuroscience, National Yang-Ming University, Taipei,
Taiwan
| | - Chia-Yi Kuan
- Division of Neurology, Department of Pediatrics, the Center for
Neurodegenerative Disease, Emory University School of Medicine, Atlanta,
Georgia, United States of America
| | - Yi-Hsuan Lee
- Department and Institute of Physiology, National Yang-Ming University,
Taipei, Taiwan
- Brain Research Center, National Yang-Ming University, Taipei,
Taiwan
- * E-mail:
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32
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Engel D, Zomkowski ADE, Lieberknecht V, Rodrigues AL, Gabilan NH. Chronic administration of duloxetine and mirtazapine downregulates proapoptotic proteins and upregulates neurotrophin gene expression in the hippocampus and cerebral cortex of mice. J Psychiatr Res 2013; 47:802-8. [PMID: 23522402 DOI: 10.1016/j.jpsychires.2013.02.013] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Accepted: 02/24/2013] [Indexed: 01/16/2023]
Abstract
Structural alterations in the limbic system, neuronal cell loss, and low levels of neurotrophins have been implicated in the pathogenesis of depression. While it is generally accepted that increasing monoamine levels in the brain can effectively alleviate depression, the precise neurobiological mechanisms involved are unclear. In the present study, we examined the effects of two antidepressants, duloxetine and mirtazapine, on the expression of apoptotic and neurotrophic proteins in the cerebral cortex and hippocampus of mice. Duloxetine (10 mg/kg) and mirtazapine (3 mg/kg) were chronically administered for 21 days, and qRT-PCR analysis was carried for the following: neurotrophins (BDNF, NGF, FGF-2, and NT-3); anti-apoptotic proteins (Bcl-2 and Bcl-xL) and pro-apoptotic proteins (Bax, Bad, and p53). Both duloxetine and mirtazapine produced antidepressant activity in the forced swimming test and induced increased cortical and hippocampal mRNA expression of BDNF. Duloxetine also increased Bcl-2, Bcl-xL, FGF-2, and NT-3 expression in the cerebral cortex, and FGF-2 expression in the hippocampus. Moreover, duloxetine reduced Bax and p53 expression in the hippocampus, and Bad expression in the cerebral cortex. Mirtazapine decreased Bcl-xL and Bax expression in the hippocampus, and Bad and p53 expression in both the hippocampus and cerebral cortex. Mirtazapine also increased the expression of neurotrophins, NGF and NT-3, in the cerebral cortex. These results suggest that duloxetine and mirtazapine could elicit their therapeutic effect by modulating the activity of apoptotic and neurotrophic pathways, thus enhancing plasticity and cell survival in depressive patients.
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Affiliation(s)
- Daiane Engel
- Departamento de Bioquímica, CCB, Universidade Federal de Santa Catarina, 88040-900, Florianópolis, SC, Brazil
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Szczytkowski JL, Lebonville C, Hutson L, Fuchs RA, Lysle DT. Heroin-induced conditioned immunomodulation requires expression of IL-1β in the dorsal hippocampus. Brain Behav Immun 2013; 30:95-102. [PMID: 23357470 PMCID: PMC3641184 DOI: 10.1016/j.bbi.2013.01.076] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2012] [Revised: 01/14/2013] [Accepted: 01/14/2013] [Indexed: 12/31/2022] Open
Abstract
Opioid-associated environmental stimuli elicit robust immune-altering effects via stimulation of a neural circuitry that includes the basolateral amygdala and nucleus accumbens. These brain regions are known to have both direct and indirect connections with the hippocampus. Thus, the present study evaluated whether the dorsal hippocampus (DH), and more specifically interleukin-1 beta (IL-1β) within the DH, is necessary for the expression of heroin-induced conditioned immunomodulation. Rats received five Pavlovian pairings of systemic heroin administration (1.0mg/kg, SC) with placement into a distinct environment (conditioned stimulus, CS). Six days after conditioning, a GABAA/B agonist cocktail or IL-1β small interfering RNA (siRNA) was microinfused into the DH to inhibit neuronal activity or IL-1β gene expression prior to CS or home cage exposure. Control animals received saline or negative control siRNA microinfusions. Furthermore, all rats received systemic administration of lipopolysaccharide (LPS) to stimulate proinflammatory nitric oxide production. CS exposure suppressed LPS-induced nitric oxide production relative to home cage exposure. Inactivation of, or IL-1β silencing in, the DH disrupted the CS-induced suppression of nitric oxide production relative to vehicle or negative control siRNA treatment. These results are the first to show a role for DH IL-1β expression in heroin-conditioned suppression of a proinflammatory immune response.
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Affiliation(s)
- Jennifer L. Szczytkowski
- University of North Carolina at Chapel Hill, Department of Psychology, CB#3270, Chapel Hill, NC 27599-3270 USA
- Messiah College, Department of Psychology, One College Avenue Suite 3052, Mechanicsburg, PA 17055 USA
| | - Christina Lebonville
- University of North Carolina at Chapel Hill, Department of Psychology, CB#3270, Chapel Hill, NC 27599-3270 USA
| | - Lee Hutson
- University of North Carolina at Chapel Hill, Department of Psychology, CB#3270, Chapel Hill, NC 27599-3270 USA
| | - Rita A. Fuchs
- University of North Carolina at Chapel Hill, Department of Psychology, CB#3270, Chapel Hill, NC 27599-3270 USA
| | - Donald T. Lysle
- University of North Carolina at Chapel Hill, Department of Psychology, CB#3270, Chapel Hill, NC 27599-3270 USA
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Chang CM, Chao CC. Protein kinase CK2 enhances Mcl-1 gene expression through the serum response factor-mediated pathway in the rat hippocampus. J Neurosci Res 2013; 91:808-17. [PMID: 23553788 DOI: 10.1002/jnr.23212] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2012] [Revised: 12/30/2012] [Accepted: 01/07/2013] [Indexed: 01/07/2023]
Abstract
The protein kinase CK2 (casein kinase 2) is a ubiquitous serine/threonine protein kinase that suppresses apoptosis. CK2 is composed of catalytic and regulatory subunits, and CK2-dependent phosphorylation is a global mechanism in the inhibition of caspase signaling pathways. The serum response factor (SRF) is an important regulator of cell growth and differentiation. Although CK2 has been shown to phosphorylate SRF in vitro, the biological relevance of this interaction remains largely unclear. We observed increased SRF phosphorylation and increased Mcl-1 gene expression in hippocampal CA1 neurons following transfection with a plasmid expressing the wild-type CK2α (CK2αWT) protein, whereas transfection with a plasmid expressing a catalytically inactive mutant of CK2α (CK2α156A) reduced Mcl-1 gene expression. Cotransfection with a plasmid expressing the inactive SRF99A mutant inhibited the CK2αWT-induced upregulation of Mcl-1 gene expression. The expression of either the CK2α156A or the SRF99A mutant also inhibited the glutamate-induced upregulation of Mcl-1 protein expression in PC12 cells. Our results suggest that CK2-mediated signaling represents a cellular mechanism that may aid in the development of alternative therapeutic strategies to attenuate apoptosis in hippocampal neurons.
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Affiliation(s)
- Chia-Ming Chang
- Institute of Neurosciences, National Chengchi University, Taipei, Taiwan
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Liu SY, Ma YL, Lee EHY. NMDA receptor signaling mediates the expression of protein inhibitor of activated STAT1 (PIAS1) in rat hippocampus. Neuropharmacology 2012; 65:101-13. [PMID: 22982248 DOI: 10.1016/j.neuropharm.2012.08.024] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2012] [Revised: 08/14/2012] [Accepted: 08/26/2012] [Indexed: 12/15/2022]
Abstract
Protein inhibitor of activated STAT1 (PIAS1) was shown to play an important role in inflammation and innate immune response, but how PIAS1 is regulated is not known. We have recently demonstrated that PIAS1 enhances spatial learning and memory performance in rats. In this study, we examined the signaling pathway and neural mechanism that regulate PIAS1 expression in the brain by using pharmacological and molecular approaches. Our results revealed that pias1 gene expression is rapidly induced upon NMDA receptor activation in rat hippocampus, but this effect is blocked by transfection of sub-threshold concentrations of ERK1 siRNA/ERK2 siRNA or CREB siRNA. Pias1 gene expression is similarly induced by overexpression of the ERK1/ERK2 plasmids in rat hippocampus, and this effect is also blocked by sub-threshold concentration of CREB siRNA transfection. On the other hand, transfection of ERK1 siRNA/ERK2 siRNA or CREB siRNA at a higher concentration is sufficient to down-regulate PIAS1 expression. Inhibition of PI-3 kinase signaling and CaMKII signaling, which both result in CREB inactivation, similarly decreases PIAS1 expression. But NMDA and MK-801 do not affect the expression of IL-6 and TNFα. NMDA also did not affect the expression of PIAS2, PIAS3 and PIAS4. Further, pias1 mRNA has a similar degradation rate to that of the zif268 gene. These results together suggest that pias1 may function as an immediate early gene in an activity-dependent manner and PIAS1 expression is regulated by the NMDA-MAPK/ERK-CREB signaling pathway implicated in neuronal plasticity.
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Affiliation(s)
- S Y Liu
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan
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Chacón PJ, Rodríguez-Tébar A. Increased expression of the homologue of enhancer-of-split 1 protects neurons from beta amyloid neurotoxicity and hints at an alternative role for transforming growth factor beta1 as a neuroprotector. ALZHEIMERS RESEARCH & THERAPY 2012; 4:31. [PMID: 22849569 PMCID: PMC3506945 DOI: 10.1186/alzrt134] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/24/2012] [Revised: 06/11/2012] [Accepted: 07/31/2012] [Indexed: 12/23/2022]
Abstract
INTRODUCTION Alzheimer's disease (AD) is a neurodegenerative disorder characterized by the deposition of β-amyloid (Aβ) in the brain, which produces progressive neuronal loss and dementia. We recently demonstrated that the noxious effects of Aβ on cultured hippocampal neurons are in part provoked by the antagonism of nerve growth factor (NGF) signalling, which impairs the activation of nuclear factor κB (NF-κB) by impeding the tyrosine phosphorylation of I-κBα. As a result, the expression of the homologue of Enhancer-of split 1 (Hes1) gene is downregulated and ultimately, gamma-aminobutyric acid (GABA)-ergic connectivity is lost. METHODS Hes1 activity was promoted in cultured hippocampal neurons by overexpressing a Hes1-encoding plasmid or by upregulating this gene by activating NF-κB through different approaches (overexpressing either the I-κB kinaseβ, or p65/RelA/NF-κB). Alternatively neurons were exposed to TGFβ1. Dendrite patterning, GABAergic connectivity and cell survival were analyzed by immunofluorescence microscopy. Hes1 expression was determined by real-time PCR. NF-κB activation was measured using the dual-luciferase reporter assay. RESULTS The expression of Hes1 abolished the effects of Aβ on dendritic patterning and GABAergic input, and it prevented the death of the cultured neurons. TGFβ1, a known neuroprotector, could counteract the deleterious effects of Aβ by inducing NF-κB activation following the serine phosphorylation of I-κBα. Indeed, the number of GABAergic terminals generated by inducing Hes1 expression was doubled. CONCLUSION Our data define some of the mechanisms involved in Aβ-mediated cell death and they point to potential means to counteract this noxious activity.
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Affiliation(s)
- Pedro J Chacón
- Centro Andaluz de Biología Molecular y Medicina Regenerativa (CABIMER), Americo Vespucio s/n, Isla de la Cartuja, 41092 Seville, Spain.
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Yang YC, Ma YL, Liu WT, Lee EHY. Laminin-β1 impairs spatial learning through inhibition of ERK/MAPK and SGK1 signaling. Neuropsychopharmacology 2011; 36:2571-86. [PMID: 21849984 PMCID: PMC3194083 DOI: 10.1038/npp.2011.148] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Laminin is a major structural element of the basal lamina consisting of an α-chain, a β-chain, and a γ-chain arranged in a cross-like structure, with their C-terminal inter-coiled. Laminin is abundantly expressed in the hippocampus of mature brain and is implicated in several psychiatric disorders, but its possible role involved in learning and memory function is not known. This issue was examined here. Our results revealed that water maze training significantly decreased laminin-β1 (LB1) expression in the rat hippocampal CA1 area. Transfection of LB1 WT plasmid to hippocampal CA1 neurons impaired water maze performance in rats. Meanwhile, it decreased the phosphorylation level of ERK/MAPK and protein kinase serum- and glucocorticoid-inducible kinase-1 (SGK1). By contrast, knockdown of endogenous LB1 expression using RNA interference (LB1 siRNA) enhanced water maze performance. Meanwhile, it increased the phosphorylation level of ERK/MAPK and SGK1. The enhancing effect of LB1 siRNA on spatial learning and on the phosphorylation of ERK/MAPK and SGK1 was blocked by co-treatment with the MEK inhibitor U0126 at a concentration that did not apparently affect spatial learning and ERK/MAPK phosphorylation alone. Further, the enhancing effect of LB1 siRNA on spatial learning and SGK1 phosphorylation was similarly blocked by co-transfection with SGK1 siRNA at a concentration that did not markedly affect spatial learning and SGK1 expression alone. These results together indicate that LB1 negatively regulates spatial learning in rats. In addition, LB1 impairs spatial learning through decreased activation of the ERK/MAPK-SGK1 signaling pathway in the rat hippocampus.
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Affiliation(s)
- Ying C Yang
- Department of Animal Science, National Ilan University, Ilan, Taiwan
| | - Yun L Ma
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Wen T Liu
- Institute of Neuroscience, National Cheng-chi University, Taipei, Taiwan
| | - Eminy HY Lee
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan,Institute of Biomedical Sciences, Academia Sinica, No.128, Sec.2, Academic Road, Taipei, 115, Taiwan. Tel: +886 2 27899125; Fax: +886 2 27829224; E-mail:
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Valproic acid inhibits neural progenitor cell death by activation of NF-κB signaling pathway and up-regulation of Bcl-XL. J Biomed Sci 2011; 18:48. [PMID: 21722408 PMCID: PMC3158748 DOI: 10.1186/1423-0127-18-48] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2011] [Accepted: 07/04/2011] [Indexed: 01/24/2023] Open
Abstract
Background At the beginning of neurogenesis, massive brain cell death occurs and more than 50% of cells are eliminated by apoptosis along with neuronal differentiation. However, few studies were conducted so far regarding the regulation of neural progenitor cells (NPCs) death during development. Because of the physiological role of cell death during development, aberration of normal apoptotic cell death is detrimental to normal organogenesis. Apoptosis occurs in not only neuron but also in NPCs and neuroblast. When growth and survival signals such as EGF or LIF are removed, apoptosis is activated as well as the induction of differentiation. To investigate the regulation of cell death during developmental stage, it is essential to investigate the regulation of apoptosis of NPCs. Methods Neural progenitor cells were cultured from E14 embryonic brains of Sprague-Dawley rats. For in vivo VPA animal model, pregnant rats were treated with VPA (400 mg/kg S.C.) diluted with normal saline at E12. To analyze the cell death, we performed PI staining and PARP and caspase-3 cleavage assay. Expression level of proteins was investigated by Western blot and immunocytochemical assays. The level of mRNA expression was investigated by RT-PCR. Interaction of Bcl-XL gene promoter and NF-κB p65 was investigated by ChIP assay. Results In this study, FACS analysis, PI staining and PARP and caspase-3 cleavage assay showed that VPA protects cultured NPCs from cell death after growth factor withdrawal both in basal and staurosporine- or hydrogen peroxide-stimulated conditions. The protective effect of prenatally injected VPA was also observed in E16 embryonic brain. Treatment of VPA decreased the level of IκBα and increased the nuclear translocation of NF-κB, which subsequently enhanced expression of anti-apoptotic protein Bcl-XL. Conclusion To the best of our knowledge, this is the first report to indicate the reduced death of NPCs by VPA at developmentally critical periods through the degradation of IκBα and the activation of NF-κB signaling. The reduced NPCs death might underlie the neurodevelopmental defects collectively called fetal valproate syndrome, which shows symptoms such as mental retardation and autism-like behavior.
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Heaton MB, Paiva M, Siler-Marsiglio K. Ethanol influences on Bax translocation, mitochondrial membrane potential, and reactive oxygen species generation are modulated by vitamin E and brain-derived neurotrophic factor. Alcohol Clin Exp Res 2011; 35:1122-33. [PMID: 21332533 DOI: 10.1111/j.1530-0277.2011.01445.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
BACKGROUND This study investigated ethanol influences on intracellular events that predispose developing neurons toward apoptosis and the capacity of the antioxidant α-tocopherol (vitamin E) and the neurotrophin brain-derived neurotrophic factor (BDNF) to modulate these effects. Assessments were made of the following: (i) ethanol-induced translocation of the pro-apoptotic Bax protein to the mitochondrial membrane, a key upstream event in the initiation of apoptotic cell death; (ii) disruption of the mitochondrial membrane potential (MMP) as a result of ethanol exposure, an important process in triggering the apoptotic cascade; and (iii) generation of damaging reactive oxygen species (ROS) as a function of ethanol exposure. METHODS These interactions were investigated in cultured postnatal day 8 neonatal rat cerebellar granule cells, a population vulnerable to developmental ethanol exposure in vivo and in vitro. Bax mitochondrial translocation was analyzed via subcellular fractionation followed by Western blot, and mitochondrial membrane integrity was determined using the lipophilic dye, JC-1, that exhibits potential-dependent accumulation in the mitochondrial membrane as a function of the MMP. RESULTS Brief ethanol exposure in these preparations precipitated Bax translocation, but both vitamin E and BDNF reduced this effect to control levels. Ethanol treatment also resulted in a disturbance of the MMP, and this effect was blunted by the antioxidant and the neurotrophin. ROS generation was enhanced by a short ethanol exposure in these cells, but the production of these harmful free radicals was diminished to control levels by cotreatment with either vitamin E or BDNF. CONCLUSIONS These results indicate that both antioxidants and neurotrophic factors have the potential to ameliorate ethanol neurotoxicity and suggest possible interventions that could be implemented in preventing or lessening the severity of the damaging effects of ethanol in the developing central nervous system seen in the fetal alcohol syndrome (FAS).
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Affiliation(s)
- Marieta B Heaton
- Department of Neuroscience, McKnight Brain Institute, Center for Alcohol Research, University of Florida College of Medicine, Gainesville, FL 32610, USA.
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