101
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Toups MS, Trivedi MH. Role of metabolic dysfunction in treatment resistance of major depressive disorder. ACTA ACUST UNITED AC 2011. [DOI: 10.2217/npy.11.49] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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102
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14-3-3 proteins in neurodegeneration. Semin Cell Dev Biol 2011; 22:696-704. [PMID: 21920445 DOI: 10.1016/j.semcdb.2011.08.005] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2011] [Accepted: 08/11/2011] [Indexed: 11/23/2022]
Abstract
Among the first reported functions of 14-3-3 proteins was the regulation of tyrosine hydroxylase (TH) activity suggesting a possible involvement of 14-3-3 proteins in Parkinson's disease. Since then the relevance of 14-3-3 proteins in the pathogenesis of chronic as well as acute neurodegenerative diseases, including Alzheimer's disease, polyglutamine diseases, amyotrophic lateral sclerosis and stroke has been recognized. The reported function of 14-3-3 proteins in this context are as diverse as the mechanism involved in neurodegeneration, reaching from basal cellular processes like apoptosis, over involvement in features common to many neurodegenerative diseases, like protein stabilization and aggregation, to very specific processes responsible for the selective vulnerability of cellular populations in single neurodegenerative diseases. Here, we review what is currently known of the function of 14-3-3 proteins in nervous tissue focussing on the properties of 14-3-3 proteins important in neurodegenerative disease pathogenesis.
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103
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Zara S, Rapino M, Sozio P, Di Stefano A, Nasuti C, Cataldi A. Ibuprofen and lipoic acid codrug 1 control Alzheimer's disease progression by down-regulating protein kinase C ε-mediated metalloproteinase 2 and 9 levels in β-amyloid infused Alzheimer's disease rat model. Brain Res 2011; 1412:79-87. [DOI: 10.1016/j.brainres.2011.07.022] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2011] [Revised: 04/21/2011] [Accepted: 07/10/2011] [Indexed: 11/29/2022]
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Colomb J, Brembs B. The biology of psychology: 'Simple' conditioning? Commun Integr Biol 2011; 3:142-5. [PMID: 20585506 DOI: 10.4161/cib.3.2.10334] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2009] [Accepted: 10/15/2009] [Indexed: 11/19/2022] Open
Abstract
Operant (instrumental) and classical (Pavlovian) conditioning are taught as the simplest forms of associative learning. Recent research in several invertebrate model systems has now accumulated evidence that the dichotomy is not as simple as it seemed. During operant learning in the fruit fly Drosophila, at least two genetically distinct learning systems interact dynamically. Inspired by analogous results in three other research fields, we propose to term one of these systems world-learning (assigning value to sensory stimuli) and the other self-learning (assigning value to a specific action or movement). During the goal-directed phase of operant learning, world-learning inhibits self-learning (in Drosophila via the mushroom-body neuropil), to allow for flexible generalization. Extended training overcomes this inhibition in a phase transition akin to habit formation in vertebrates, allowing self-learning to transform spontaneous actions to habitual responses. In part, these insights were achieved by reducing operant experiments beyond the traditional set-ups (i.e., 'pure' operant learning) and using modern, molecular and/or genetic model systems.
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Affiliation(s)
- Julien Colomb
- Freie Universität Berlin; Institut für Biologie-Neurobiologie; Berlin, Germany
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105
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Shi S, Shi R, Hashizume K. American ginseng improves neurocognitive function in senescence-accelerated mice: possible role of the upregulated insulin and choline acetyltransferase gene expression. Geriatr Gerontol Int 2011; 12:123-30. [PMID: 21702872 DOI: 10.1111/j.1447-0594.2011.00719.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
AIM To investigate the effects of American ginseng on neurocognitive function and glucose regulation in senescence-accelerated mice. METHODS Male senescence-resistant inbred strains (SAMR1) and senescence-prone inbred strains (SAMP10) mice were divided into five groups and fed either a control diet or an American ginseng-supplemented diet (1% or 2% g/g) from 6 weeks to 10 months of age. Bodyweight, levels of fasting plasma glucose (FPG) and grading scores were monitored every month and neurocognitive functions were evaluated at 9 months of age with a KUROBOX apparatus using a stress-free positive cue task. Gene expressions of peroxisome proliferator-activated receptor delta (PPAR-δ), insulin, choline acetyltransferase (ChAT) and amyloid precursor protein (APP) in the brain were measured by real-time quantitative reverse transcription polymerase chain reaction assays. RESULTS American ginseng decreased FPG in SAMR1 mice, but increased FPG in SAMP10 mice. Correct visit ratios were higher in both SAMR1 and SAMP10 strains consuming an American ginseng-supplemented diet. Gene upregulation of insulin and ChAT in the brain, but not of PPAR-δ or APP, was evident in American ginseng-fed groups. CONCLUSION Daily consumption of American ginseng induced an enhancement in neurocognitive function in senescence-accelerated mice, which could be related to the upregulation of insulin and ChAT gene expression in the brain. Geriatr Gerontol Int 2012; 12: 123-130.
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Affiliation(s)
- Shun Shi
- Department of Aging Medicine and Geriatrics, Institute on Aging and Adaptation, Shinshu University Graduate School of Medicine, Matsumoto, Japan.
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106
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Yi H, Kim SH, Park HG, Yu HS, Kim YS. The effect of systemic injection of cyclosporin A on the phosphorylation of the PKC substrates MARCKS and GAP43 in the rat hippocampus. Neurosci Lett 2011; 497:17-21. [DOI: 10.1016/j.neulet.2011.04.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2011] [Revised: 03/16/2011] [Accepted: 04/07/2011] [Indexed: 12/21/2022]
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Differential effects of treadmill exercise in early and chronic diabetic stages on parvalbumin immunoreactivity in the hippocampus of a rat model of type 2 diabetes. Neurochem Res 2011; 36:1526-32. [PMID: 21516442 DOI: 10.1007/s11064-011-0480-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/15/2011] [Indexed: 12/23/2022]
Abstract
In the present study, we investigated the effects of treadmill exercise in early and chronic diabetic stages on parvalbumin (PV) immunoreactivity in the subgranular zone of the dentate gyrus of Zucker diabetic fatty (ZDF) and its lean control rats (ZLC). To investigate the effects, ZLC and ZDF rats at 6 or 23 weeks of age were put on a treadmill with or without running for 1 h/day/5 consecutive days at 16-22 m/min for 5 weeks or 12-16 m/min for 7 weeks, respectively. Physical exercise in pre-diabetic rats prevented onset of diabetes, while exercise in rats at chronic diabetic stage significantly reduced blood glucose levels. In addition, physical exercise in the pre-diabetic rats significantly increased PV immunoreactive fibers in the strata oriens and radiatum of the CA1-3 region and in the polymorphic and molecular layers of the dentate gyrus compared to that in sedentary controls. However, in rats at chronic stages, PV immunoreactivity was slightly increased in the CA1-3 region as well as in the dentate gyrus compared to that in the sedentary controls. These results suggest that physical exercise has differential effects on blood glucose levels and PV immunoreactivity according to diabetic stages. Early exercise improves diabetic phenotype and PV immunoreactive fibers in the rat hippocampus.
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Ooi CP, Loke SC, Yassin Z, Hamid T. Carbohydrates for improving the cognitive performance of independent-living older adults with normal cognition or mild cognitive impairment. Cochrane Database Syst Rev 2011; 2011:CD007220. [PMID: 21491398 PMCID: PMC7388979 DOI: 10.1002/14651858.cd007220.pub2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
BACKGROUND Mild cognitive impairment (MCI) is an intermediate state between normal cognition and dementia in which daily function is largely intact. This condition may present an opportunity for research into the prevention of dementia. Carbohydrate is an essential and easily accessible macronutrient which influences cognitive performance. A better understanding of carbohydrate-driven cognitive changes in normal cognition and mild cognitive impairment may suggest ways to prevent or reduce cognitive decline. OBJECTIVES To assess the effectiveness of carbohydrates in improving cognitive function in older adults. SEARCH STRATEGY We searched ALOIS, the Cochrane Dementia and Cognitive Improvement Group Specialized Register on 22 June 2010 using the terms: carbohydrates OR carbohydrate OR monosaccharides OR disaccharides OR oligosaccharides OR polysaccharides OR CARBS. ALOIS contains records from all major healthcare databases (The Cochrane Library, MEDLINE, EMBASE, PsycINFO, CINAHL, LILACS) as well as from many trial databases and grey literature sources. SELECTION CRITERIA All randomised controlled trials (RCT) that have examined the efficacy of any form of carbohydrates in normal cognition and MCI. DATA COLLECTION AND ANALYSIS One review author selected and retrieved relevant articles for further assessment. The remaining authors independently assessed whether any of the retrieved trials should be included. Disagreements were resolved by discussion. MAIN RESULTS There is no suitable RCT of any form of carbohydrates involving independent-living older adults with normal cognition or mild cognitive impairment. AUTHORS' CONCLUSIONS There are no suitable RCTs on which to base any recommendations about the use of any form of carbohydrate for enhancing cognitive performance in older adults with normal cognition or mild cognitive impairment. More studies of many different carbohydrates are needed to tease out complex nutritional issues and further evaluate memory improvement.
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Affiliation(s)
- Cheow Peng Ooi
- Faculty of Medicine and Health Sciences, Universiti Putra MalaysiaEndocrine Unit, Department of MedicineSerdangSelangor DEMalaysia43400
| | - Seng Cheong Loke
- Universiti Putra MalaysiaInstitute of GerontologySerdangSelangor DEMalaysia43400
| | - Zaitun Yassin
- University Putra MalaysiaDepartment of Nutrition and Dietetics, Faculty of Medicine & Health Sciences43400 UPM SerdangSelangorMalaysia
| | - Tengku‐Aizan Hamid
- Universiti Putra MalaysiaInstitute of GerontologySerdangSelangor DEMalaysia43400
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109
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Zhang HM, Lin N, Dong Y, Su Q, Luo M. Effect of perinatal thyroid hormone deficiency on expression of rat hippocampal conventional protein kinase C isozymes. Mol Cell Biochem 2011; 353:65-71. [DOI: 10.1007/s11010-011-0775-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2010] [Accepted: 02/24/2011] [Indexed: 11/30/2022]
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110
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Mielke JG, Wang YT. Insulin, synaptic function, and opportunities for neuroprotection. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2011; 98:133-86. [PMID: 21199772 DOI: 10.1016/b978-0-12-385506-0.00004-1] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
A steadily growing number of studies have begun to establish that the brain and insulin, while traditionally viewed as separate, do indeed have a relationship. The uptake of pancreatic insulin, along with neuronal biosynthesis, provides neural tissue with the hormone. As well, insulin acts upon a neuronal receptor that, although a close reflection of its peripheral counterpart, is characterized by unique structural and functional properties. One distinction is that the neural variant plays only a limited part in neuronal glucose transport. However, a number of other roles for neural insulin are gradually emerging; most significant among these is the modulation of ligand-gated ion channel (LGIC) trafficking. Notably, insulin has been shown to affect the tone of synaptic transmission by regulating cell-surface expression of inhibitory and excitatory receptors. The manner in which insulin regulates receptor movement may provide a cellular mechanism for insulin-mediated neuroprotection in the absence of hypoglycemia and stimulate the exploration of new therapeutic opportunities.
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Affiliation(s)
- John G Mielke
- Faculty of Applied Health Sciences, Department of Health Studies and Gerontology, University of Waterloo, Waterloo, Ontario, Canada
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111
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Betti M, Ambrogini P, Minelli A, Floridi A, Lattanzi D, Ciuffoli S, Bucherelli C, Prospero E, Frontini A, Santarelli L, Baldi E, Benetti F, Galli F, Cuppini R. Maternal dietary loads of α-tocopherol depress protein kinase C signaling and synaptic plasticity in rat postnatal developing hippocampus and promote permanent deficits in adult offspring. J Nutr Biochem 2011; 22:60-70. [DOI: 10.1016/j.jnutbio.2009.11.014] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2009] [Revised: 11/17/2009] [Accepted: 11/30/2009] [Indexed: 01/12/2023]
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112
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Giorgi C, Agnoletto C, Baldini C, Bononi A, Bonora M, Marchi S, Missiroli S, Patergnani S, Poletti F, Rimessi A, Zavan B, Pinton P. Redox control of protein kinase C: cell- and disease-specific aspects. Antioxid Redox Signal 2010; 13:1051-85. [PMID: 20136499 DOI: 10.1089/ars.2009.2825] [Citation(s) in RCA: 286] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Hormones, growth factors, electrical stimulation, and cell-cell interactions regulate numerous cellular processes by altering the levels of second messengers, thus influencing biochemical reactions inside the cells. The Protein Kinase C family (PKCs) is a group of serine/threonine kinases that are dependent on calcium (Ca(2+)), diacylglycerol, and phospholipids. Signaling pathways that induce variations on the levels of PKC activators have been implicated in the regulation of diverse cellular functions and, in turn, PKCs are key regulators of a plethora of cellular processes, including proliferation, differentiation, and tumorigenesis. Importantly, PKCs contain regions, both in the N-terminal regulatory domain and in the C-terminal catalytic domain, that are susceptible to redox modifications. In several pathophysiological conditions when the balance between oxidants, antioxidants, and alkylants is compromised, cells undergo redox stress. PKCs are cell-signaling proteins that are particularly sensitive to redox stress because modification of their redox-sensitive regions interferes with their activity and, thus, with their biological effects. In this review, we summarize the involvement of PKCs in health and disease and the importance of redox signaling in the regulation of this family of kinases.
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Affiliation(s)
- Carlotta Giorgi
- Department of Experimental and Diagnostic Medicine, Section of General Pathology, Interdisciplinary Center for the Study of Inflammation (ICSI), BioPharmaNet, University of Ferrara, Ferrara, Italy
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113
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De Gasperi R, Sosa MAG, Dracheva S, Elder GA. Presenilin-1 regulates induction of hypoxia inducible factor-1α: altered activation by a mutation associated with familial Alzheimer's disease. Mol Neurodegener 2010; 5:38. [PMID: 20863403 PMCID: PMC2955646 DOI: 10.1186/1750-1326-5-38] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2010] [Accepted: 09/23/2010] [Indexed: 12/23/2022] Open
Abstract
Background Mutations in presenilin-1 (Psen1) cause familial Alzheimer's disease (FAD). Both hypoxia and ischemia have been implicated in the pathological cascade that leads to amyloid deposition in AD. Here we investigated whether Psen1 might regulate hypoxic responses by modulating induction of the transcription factor hypoxia inducible factor 1-α (HIF-1α). Results In fibroblasts that lack Psen1 induction of HIF-1α was impaired in response to the hypoxia mimetic cobalt chloride, as well as was induction by insulin and calcium chelation. Reintroduction of human Psen1 using a lentiviral vector partially rescued the responsiveness of Psen1-/- fibroblasts to cobalt chloride induction. HIF-1α induction did not require Psen1's associated γ-secretase activity. In addition, the failure of insulin to induce HIF-1α was not explicable on the basis of failed activation of the phosphatidylinositol 3-kinase (PI3K/Akt) pathway which activated normally in Psen1-/- fibroblasts. Rather we found that basal levels of HIF-1α were lower in Psen1-/- fibroblasts and that the basis for lower constitutive levels of HIF-1α was best explained by accelerated HIF-1α degradation. We further found that Psen1 and HIF-1α physically interact suggesting that Psen1 may protect HIF-1α from degradation through the proteasome. In fibroblasts harboring the M146V Psen1 FAD mutation on a mouse Psen1 null background, metabolic induction of HIF-1α by insulin was impaired but not hypoxic induction by cobalt chloride. Unlike Psen1-/- fibroblasts, basal levels of HIF-1α were normal in FAD mutant fibroblasts but activation of the insulin-receptor pathway was impaired. Interestingly, in Psen1-/- primary neuronal cultures HIF-1α was induced normally in response to cobalt chloride but insulin induction of HIF-1α was impaired even though activation of the PI3K/Akt pathway by insulin proceeded normally in Psen1-/- neuronal cultures. Basal levels of HIF-1α were not significantly different in Psen1-/- neurons and HIF-1α levels were normal in Psen1-/- embryos. Conclusions Collectively these studies show that Psen1 regulates induction of HIF-1α although they indicate that cell type specific differences exist in the effect of Psen1 on induction. They also show that the M146V Psen1 FAD mutation impairs metabolic induction of HIF-1α, an observation that may have pathophysiological significance for AD.
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Affiliation(s)
- Rita De Gasperi
- Neurology Service, James J Peters Department of Veterans Affairs Medical Center, Bronx, NY 10468, USA.
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114
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Hoffman WH, Andjelkovic AV, Zhang W, Passmore GG, Sima AAF. Insulin and IGF-1 receptors, nitrotyrosin and cerebral neuronal deficits in two young patients with diabetic ketoacidosis and fatal brain edema. Brain Res 2010; 1343:168-77. [PMID: 20420811 DOI: 10.1016/j.brainres.2010.04.042] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2010] [Revised: 04/15/2010] [Accepted: 04/16/2010] [Indexed: 12/16/2022]
Abstract
Gray and white matter structural deficits may accompany type 1 diabetes. Earlier experimental studies have demonstrated neuronal deficits associated with impaired neurotrophic support, inflammation and oxidative stress. In this study we demonstrate in two patients with histories of poorly controlled type 1 diabetes and fatal brain edema of ketoacidosis neuronal deficits associated with a decreased presence of insulin and IGF-1 receptors and accumulation of nitrotyrosin in neurons of affected areas and the choroid plexus. The findings add support to the suggested genesis of T1DM encephalopathy due to compromised neurotrophic protection, oxidative stress, inflammation and neuronal deficits, as demonstrated in T1DM encephalopathy in the BB/Wor-rat.
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Affiliation(s)
- William H Hoffman
- Department of Pediatrics, Section of Pediatric Endocrinology, Medical College of Georgia, Augusta, GA, USA.
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115
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Kim SH, Kim MK, Yu HS, Kim HS, Park IS, Park HG, Kang UG, Kim YS. Electroconvulsive seizure increases phosphorylation of PKC substrates, including GAP-43, MARCKS, and neurogranin, in rat brain. Prog Neuropsychopharmacol Biol Psychiatry 2010; 34:115-21. [PMID: 19837121 DOI: 10.1016/j.pnpbp.2009.10.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2009] [Revised: 10/08/2009] [Accepted: 10/08/2009] [Indexed: 01/06/2023]
Abstract
Protein kinase C (PKC) has been suggested as a molecular target related to the pathogenetic and therapeutic mechanisms of mood disorders in which electroconvulsive seizure (ECS) is effective. However, the reports concerning the effects of ECS on PKC are anecdotal and need further clarification. In this study, we examined the effects of ECS treatment on the phosphorylation of PKC substrates, including GAP-43, MARCKS, and neurogranin. Immunoblot using anti-p-PKC substrate antibodies revealed that a single ECS treatment induced temporal changes in the phosphorylation level of PKC substrates in rat brain, reflecting the effects on PKC activity. Phosphorylation of GAP-43 and MARCKS, representative PKC substrates related to synaptic remodeling, increased from 5 to 30 min, after a transient decrease at 0 min immediately after ECS, and returned to basal levels at 60 min in rat frontal cortex, hippocampus, and cerebellum. Phosphorylation of neurogranin, another PKC substrate, showed a similar pattern of temporal changes in the frontal cortex and hippocampus. Immunohistochemical analysis revealed that p-GAP-43 and p-MARCKS were densely stained throughout the neuronal cells of the prefrontal cortex and hippocampus, and the Purkinje cells of cerebellum, after ECS treatment. Brief and transient activation of PKC may be translated into long-term biochemical changes, resulting in synaptic plasticity. Taken together, the acute effects of ECS on PKC activity, which could be an underpinning of long-term biochemical changes induced by ECS, may contribute to understand the molecular mechanism of ECS.
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Affiliation(s)
- Se Hyun Kim
- Department of Psychiatry and Behavioral Science and Institute of Human Behavioral Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
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116
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Yong QC, Choo CH, Tan BH, Low CM, Bian JS. Effect of hydrogen sulfide on intracellular calcium homeostasis in neuronal cells. Neurochem Int 2010; 56:508-15. [DOI: 10.1016/j.neuint.2009.12.011] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2009] [Revised: 12/08/2009] [Accepted: 12/16/2009] [Indexed: 11/16/2022]
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Sun MK, Alkon DL. Protein kinase C activators as synaptogenic and memory therapeutics. Arch Pharm (Weinheim) 2010; 342:689-98. [PMID: 19899099 DOI: 10.1002/ardp.200900050] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The last decade has witnessed a rapid progress in understanding of the molecular cascades that may underlie memory and memory disorders. Among the critical players, activity of protein kinase C (PKC) isoforms is essential for many types of learning and memory and their dysfunction, and is critical in memory disorders. PKC inhibition and functional deficits lead to an impairment of various types of learning and memory, consistent with the observations that neurotoxic amyloid inhibits PKC activity and that transgenic animal models with PKCbeta deficit exhibit impaired capacity in cognition. In addition, PKC isozymes play a regulatory role in amyloid production and accumulation. Restoration of the impaired PKC signal pathway pharmacologically results in an enhanced memory capacity and synaptic remodeling / repair and synaptogenesis, and, therefore, represents a potentially important strategy for the treatment of memory disorders, including Alzheimer's dementia. The PKC activators, especially those that are isozyme-specific, are a new class of drug candidates that may be developed as future memory therapeutics.
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Affiliation(s)
- Miao-Kun Sun
- Blanchette Rockefeller Neurosciences Institute, Rockville, MD 20850, USA.
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118
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Asmussen JW, Von Sperling ML, Penkowa M. Intraneuronal signaling pathways of metallothionein. J Neurosci Res 2010; 87:2926-36. [PMID: 19405100 DOI: 10.1002/jnr.22118] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Metallothionein (MT) belongs to a family of metal-binding cysteine-rich proteins comprising several structurally related proteins implicated in tissue protection and regeneration after injuries and functioning as antiapoptotic antioxidants in neurological disorders. This has been demonstrated in animals receiving MT treatment and in mice with endogenous MT overexpression or null mutation during various experimental models of neuropathology, and also in patients with Alzheimer's disease and amyotrophic lateral sclerosis. Exogenously applied MT increases neurite outgrowth and neuronal survival in rat cerebellar, hippocampal, dopaminergic, and cortical neurons in vitro. In this study, the intraneuronal signaling involved in MT-mediated neuritogenesis was examined. The MT-induced neurite outgrowth in cultures of cerebellar granule neurons was dependent on activation of a heterotrimeric G-protein-coupled pathway but not on protein tyrosine kinases or on receptor tyrosine kinases. Activation of phospholipase C was necessary for MT-induced neurite outgrowth, and furthermore it was shown that inhibition of several intracellular protein kinases, such as protein kinase A, protein kinase C, phosphatidylinositol 3-kinase, Ca(2+)/calmodulin kinase-II, and mitogen-activated protein kinase kinase, abrogated the MT-mediated neuritogenic response. In addition, exogenously applied MT resulted in a decrease in phosphorylation of intraneuronal kinases implicated in proinflammatory reactions and apoptotic cell death, such as glycogen synthase-serine kinase 3alpha, Jun, and signal transducer and activator of transcription 3. This paper elucidates the intraneuronal molecular signaling involved in neuroprotective effects of MT.
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Affiliation(s)
- Johanne Wirenfeldt Asmussen
- Section of Neuroprotection, Institute of Neuroscience and Pharmacology, University of Copenhagen, Copenhagen, Denmark.
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119
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Sun MK, Nelson TJ, Alkon DL. PKC and Insulin Pathways in Memory Storage: Targets for Synaptogenesis, Anti-apoptosis, and the Treatment of AD. DIABETES, INSULIN AND ALZHEIMER'S DISEASE 2010. [DOI: 10.1007/978-3-642-04300-0_10] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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120
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Cardoso S, Santos R, Correia S, Carvalho C, Zhu X, Lee HG, Casadesus G, Smith MA, Perry G, Moreira PI. Insulin and Insulin-Sensitizing Drugs in Neurodegeneration: Mitochondria as Therapeutic Targets. Pharmaceuticals (Basel) 2009; 2:250-286. [PMID: 27713238 PMCID: PMC3978547 DOI: 10.3390/ph2030250] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2009] [Revised: 12/21/2009] [Accepted: 12/22/2009] [Indexed: 12/13/2022] Open
Abstract
Insulin, besides its glucose lowering effects, is involved in the modulation of lifespan, aging and memory and learning processes. As the population ages, neurodegenerative disorders become epidemic and a connection between insulin signaling dysregulation, cognitive decline and dementia has been established. Mitochondria are intracellular organelles that despite playing a critical role in cellular metabolism are also one of the major sources of reactive oxygen species. Mitochondrial dysfunction, oxidative stress and neuroinflammation, hallmarks of neurodegeneration, can result from impaired insulin signaling. Insulin-sensitizing drugs such as the thiazolidinediones are a new class of synthetic compounds that potentiate insulin action in the target tissues and act as specific agonists of the peroxisome proliferator-activated receptor gamma (PPAR-γ). Recently, several PPAR agonists have been proposed as novel and possible therapeutic agents for neurodegenerative disorders. Indeed, the literature shows that these agents are able to protect against mitochondrial dysfunction, oxidative damage, inflammation and apoptosis. This review discusses the role of mitochondria and insulin signaling in normal brain function and in neurodegeneration. Furthermore, the potential protective role of insulin and insulin sensitizers in Alzheimer´s, Parkinson´s and Huntington´s diseases and amyotrophic lateral sclerosis will be also discussed.
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Affiliation(s)
- Susana Cardoso
- Center for Neuroscience and Cell Biology, University of Coimbra, 3000-354 Coimbra, Portugal
- Department of Life Sciences, Faculty of Sciences and Technology, University of Coimbra, 3000- 354 Coimbra, Portugal
| | - Renato Santos
- Center for Neuroscience and Cell Biology, University of Coimbra, 3000-354 Coimbra, Portugal
- Department of Life Sciences, Faculty of Sciences and Technology, University of Coimbra, 3000- 354 Coimbra, Portugal
| | - Sonia Correia
- Center for Neuroscience and Cell Biology, University of Coimbra, 3000-354 Coimbra, Portugal
- Department of Life Sciences, Faculty of Sciences and Technology, University of Coimbra, 3000- 354 Coimbra, Portugal
| | - Cristina Carvalho
- Center for Neuroscience and Cell Biology, University of Coimbra, 3000-354 Coimbra, Portugal
- Department of Life Sciences, Faculty of Sciences and Technology, University of Coimbra, 3000- 354 Coimbra, Portugal
| | - Xiongwei Zhu
- School of Medicine, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Hyoung-Gon Lee
- School of Medicine, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Gemma Casadesus
- School of Medicine, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Mark A Smith
- School of Medicine, Case Western Reserve University, Cleveland, OH 44106, USA
| | - George Perry
- College of Sciences, The University of Texas at San Antonio, TX 78249, USA
| | - Paula I Moreira
- Center for Neuroscience and Cell Biology, University of Coimbra, 3000-354 Coimbra, Portugal.
- Institute of Physiology, Faculty of Medicine, University of Coimbra, 3000-354 Coimbra, Portugal.
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Hwang IK, Yi SS, Song W, Won MH, Yoon YS, Seong JK. Effects of age and treadmill exercise in chronic diabetic stages on neuroblast differentiation in a rat model of type 2 diabetes. Brain Res 2009; 1341:63-71. [PMID: 20005869 DOI: 10.1016/j.brainres.2009.12.009] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2009] [Revised: 11/26/2009] [Accepted: 12/03/2009] [Indexed: 01/21/2023]
Abstract
In the present study, we investigated the effects of type 2 diabetes and treadmill exercise in chronic diabetic stages on neuroblast differentiation using doublecortin (DCX) in the subgranular zone of the dentate gyrus (SZDG) in Zucker diabetic fatty (ZDF) rats. Four-, 12-, 20- and 30-week-old Zucker lean control (ZLC) and ZDF rats were used to elucidate age-dependent changes of DCX-immunoreactive neuroblasts. DCX-immunoreactive neuroblasts were significantly decreased with age in the SZDG. This reduction was prominent in the age-matched ZDF rats compared to that in the ZLC rats. To investigate the effects of treadmill exercise, ZLC and ZDF rats at 23 weeks of age were put on the treadmill with or without running for 1 h/day/5 consecutive days at 12-16 m/min for 7 weeks. Treadmill exercise significantly increased the tertiary dendrites of DCX-immunoreactive neuroblasts in both ZLC and ZDF rats. In addition, exercise significantly increased the number of DCX-immunoreactive neuroblasts in the ZLC rats, but not in the ZDF rats. These results suggest that diabetes significantly decreases neuroblast differentiation and treadmill exercise in chronic diabetic animals has limitation to increase neuroblast differentiation although it increases neural plasticity.
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Affiliation(s)
- In Koo Hwang
- Department of Anatomy and Cell Biology, College of Veterinary Medicine and BK21 Program for Veterinary Science, Seoul National University, Seoul 151-742, South Korea
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Tsolaki M, Kounti F, Karamavrou S. Severe psychological stress in elderly individuals: a proposed model of neurodegeneration and its implications. Am J Alzheimers Dis Other Demen 2009; 24:85-94. [PMID: 19193610 PMCID: PMC10846216 DOI: 10.1177/1533317508329813] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
During clinical practice, degenerative diseases in some patients appear after exposure to a severe psychological stress. Several studies have suggested that the duration of exposure to corticosteroids or stress, the dose of corticosteroids and the vulnerability of the hippocampus, amygdala and prefrontal cortex areas targeted by elevated stress hormones, mediate the damaging effects of elevated corticosteroids. Although understanding what triggers the transition from adaptive plasticity to the maladaptive effects of stress in the elderly is important, one of the great challenges is to determine individual differences in vulnerability to stress-induced events in both animal and human populations, and to devise strategies that may help protecting the brain from permanent damage. This review provides the basis for creating interventions and educational programs during midlife in order to prevent dementia or other neurodegenerative diseases or to halt the progress of neurodegeneration in the early stages.
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Affiliation(s)
- Magda Tsolaki
- 3rd Department of Neurology, Medical School, Aristotle University of Thessaloniki, Thessaloniki, Greece.
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