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Folch J, Ettcheto M, Busquets O, Sánchez-López E, Castro-Torres RD, Verdaguer E, Manzine PR, Poor SR, García ML, Olloquequi J, Beas-Zarate C, Auladell C, Camins A. The Implication of the Brain Insulin Receptor in Late Onset Alzheimer's Disease Dementia. Pharmaceuticals (Basel) 2018; 11:E11. [PMID: 29382127 PMCID: PMC5874707 DOI: 10.3390/ph11010011] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Revised: 01/24/2018] [Accepted: 01/25/2018] [Indexed: 12/16/2022] Open
Abstract
Alzheimer's disease (AD) is progressive neurodegenerative disorder characterized by brain accumulation of the amyloid β peptide (Aβ), which form senile plaques, neurofibrillary tangles (NFT) and, eventually, neurodegeneration and cognitive impairment. Interestingly, epidemiological studies have described a relationship between type 2 diabetes mellitus (T2DM) and this pathology, being one of the risk factors for the development of AD pathogenesis. Information as it is, it would point out that, impairment in insulin signalling and glucose metabolism, in central as well as peripheral systems, would be one of the reasons for the cognitive decline. Brain insulin resistance, also known as Type 3 diabetes, leads to the increase of Aβ production and TAU phosphorylation, mitochondrial dysfunction, oxidative stress, protein misfolding, and cognitive impairment, which are all hallmarks of AD. Moreover, given the complexity of interlocking mechanisms found in late onset AD (LOAD) pathogenesis, more data is being obtained. Recent evidence showed that Aβ42 generated in the brain would impact negatively on the hypothalamus, accelerating the "peripheral" symptomatology of AD. In this situation, Aβ42 production would induce hypothalamic dysfunction that would favour peripheral hyperglycaemia due to down regulation of the liver insulin receptor. The objective of this review is to discuss the existing evidence supporting the concept that brain insulin resistance and altered glucose metabolism play an important role in pathogenesis of LOAD. Furthermore, we discuss AD treatment approaches targeting insulin signalling using anti-diabetic drugs and mTOR inhibitors.
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Affiliation(s)
- Jaume Folch
- Departament de Bioquímica i Biotecnologia, Facultat de Medicina i Ciències de la Salut, Universitat Rovira i Virgili, 43201 Reus, Spain.
- Biomedical Research Networking Centre in Neurodegenerative Diseases (CIBERNED), 28031 Madrid, Spain.
| | - Miren Ettcheto
- Departament de Bioquímica i Biotecnologia, Facultat de Medicina i Ciències de la Salut, Universitat Rovira i Virgili, 43201 Reus, Spain.
- Biomedical Research Networking Centre in Neurodegenerative Diseases (CIBERNED), 28031 Madrid, Spain.
- Departament de Farmacologia, Toxicologia i Química Terapèutica, Facultat de Farmàcia i Ciències de l'Alimentació, Universitat de Barcelona, Av. Joan XXIII 27/31, E-08028 Barcelona, Spain.
- Institut de Neurociències, Universitat de Barcelona, E-08028 Barcelona, Spain.
| | - Oriol Busquets
- Departament de Bioquímica i Biotecnologia, Facultat de Medicina i Ciències de la Salut, Universitat Rovira i Virgili, 43201 Reus, Spain.
- Biomedical Research Networking Centre in Neurodegenerative Diseases (CIBERNED), 28031 Madrid, Spain.
- Departament de Farmacologia, Toxicologia i Química Terapèutica, Facultat de Farmàcia i Ciències de l'Alimentació, Universitat de Barcelona, Av. Joan XXIII 27/31, E-08028 Barcelona, Spain.
- Institut de Neurociències, Universitat de Barcelona, E-08028 Barcelona, Spain.
| | - Elena Sánchez-López
- Biomedical Research Networking Centre in Neurodegenerative Diseases (CIBERNED), 28031 Madrid, Spain.
- Unitat de Farmàcia, Tecnologia Farmacèutica i Fisico-química, Facultat de Farmàcia i Ciències de l'Alimentació, Universitat de Barcelona, E-08028 Barcelona, Spain.
- Institute of Nanoscience and Nanotechnology (IN2UB), University of Barcelona, Barcelona E-08028, Spain.
| | - Rubén D Castro-Torres
- Biomedical Research Networking Centre in Neurodegenerative Diseases (CIBERNED), 28031 Madrid, Spain.
- Departament de Farmacologia, Toxicologia i Química Terapèutica, Facultat de Farmàcia i Ciències de l'Alimentació, Universitat de Barcelona, Av. Joan XXIII 27/31, E-08028 Barcelona, Spain.
- Institut de Neurociències, Universitat de Barcelona, E-08028 Barcelona, Spain.
- Departament de Biologia Cel·lular, Fisiologia i Immunologia, Facultat de Biologia, Universitat de Barcelona, E-08028 Barcelona, Spain.
- Laboratorio de Regeneración y Desarrollo Neural, Instituto de Neurobiología, Departamento de Biología Celular y Molecular, Centro Universitario de Ciencias Biológicas y Agropecuarias, Universidad de Guadalajara, Zapopan 44600, Mexico.
| | - Ester Verdaguer
- Biomedical Research Networking Centre in Neurodegenerative Diseases (CIBERNED), 28031 Madrid, Spain.
- Institut de Neurociències, Universitat de Barcelona, E-08028 Barcelona, Spain.
- Departament de Biologia Cel·lular, Fisiologia i Immunologia, Facultat de Biologia, Universitat de Barcelona, E-08028 Barcelona, Spain.
| | - Patricia R Manzine
- Departament de Farmacologia, Toxicologia i Química Terapèutica, Facultat de Farmàcia i Ciències de l'Alimentació, Universitat de Barcelona, Av. Joan XXIII 27/31, E-08028 Barcelona, Spain.
- Department of Gerontology, Federal University of São Carlos (UFSCar), São Carlos 13565-905, Brazil.
| | - Saghar Rabiei Poor
- Departament de Farmacologia, Toxicologia i Química Terapèutica, Facultat de Farmàcia i Ciències de l'Alimentació, Universitat de Barcelona, Av. Joan XXIII 27/31, E-08028 Barcelona, Spain.
| | - María Luisa García
- Unitat de Farmàcia, Tecnologia Farmacèutica i Fisico-química, Facultat de Farmàcia i Ciències de l'Alimentació, Universitat de Barcelona, E-08028 Barcelona, Spain.
- Institute of Nanoscience and Nanotechnology (IN2UB), University of Barcelona, Barcelona E-08028, Spain.
| | - Jordi Olloquequi
- Instituto de Ciencias Biomédicas, Facultad de Ciencias de la Salud, Universidad Autónoma de Chile, Talca 3460000, Chile.
| | - Carlos Beas-Zarate
- Laboratorio de Regeneración y Desarrollo Neural, Instituto de Neurobiología, Departamento de Biología Celular y Molecular, Centro Universitario de Ciencias Biológicas y Agropecuarias, Universidad de Guadalajara, Zapopan 44600, Mexico.
| | - Carme Auladell
- Biomedical Research Networking Centre in Neurodegenerative Diseases (CIBERNED), 28031 Madrid, Spain.
- Institut de Neurociències, Universitat de Barcelona, E-08028 Barcelona, Spain.
- Departament de Biologia Cel·lular, Fisiologia i Immunologia, Facultat de Biologia, Universitat de Barcelona, E-08028 Barcelona, Spain.
| | - Antoni Camins
- Biomedical Research Networking Centre in Neurodegenerative Diseases (CIBERNED), 28031 Madrid, Spain.
- Departament de Farmacologia, Toxicologia i Química Terapèutica, Facultat de Farmàcia i Ciències de l'Alimentació, Universitat de Barcelona, Av. Joan XXIII 27/31, E-08028 Barcelona, Spain.
- Institut de Neurociències, Universitat de Barcelona, E-08028 Barcelona, Spain.
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Deochand C, Tong M, Agarwal AR, Cadenas E, de la Monte SM. Tobacco Smoke Exposure Impairs Brain Insulin/IGF Signaling: Potential Co-Factor Role in Neurodegeneration. J Alzheimers Dis 2016; 50:373-86. [PMID: 26682684 DOI: 10.3233/jad-150664] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND Human studies suggest tobacco smoking is a risk factor for cognitive impairment and neurodegeneration, including Alzheimer's disease (AD). However, experimental data linking tobacco smoke exposures to underlying mediators of neurodegeneration, including impairments in brain insulin and insulin-like growth factor (IGF) signaling in AD are lacking. OBJECTIVE This study tests the hypothesis that cigarette smoke (CS) exposures can impair brain insulin/IGF signaling and alter expression of AD-associated proteins. METHODS Adult male A/J mice were exposed to air for 8 weeks (A8), CS for 4 or 8 weeks (CS4, CS8), or CS8 followed by 2 weeks recovery (CS8+R). Gene expression was measured by qRT-PCR analysis and proteins were measured by multiplex bead-based or direct binding duplex ELISAs. RESULTS CS exposure effects on insulin/IGF and insulin receptor substrate (IRS) proteins and phosphorylated proteins were striking compared with the mRNA. The main consequences of CS4 or CS8 exposures were to significantly reduce insulin R, IGF-1R, IRS-1, and tyrosine phosphorylated insulin R and IGF-1R proteins. Paradoxically, these effects were even greater in the CS8+R group. In addition, relative levels of S312-IRS-1, which inhibits downstream signaling, were increased in the CS4, CS8, and CS8+R groups. Correspondingly, CS and CS8+R exposures inhibited expression of proteins and phosphoproteins required for signaling through Akt, PRAS40, and/or p70S6K, increased AβPP-Aβ, and reduced ASPH protein, which is a target of insulin/IGF-1 signaling. CONCLUSION Secondhand CS exposures caused molecular and biochemical abnormalities in brain that overlap with the findings in AD, and many of these effects were sustained or worsened despite short-term CS withdrawal.
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Affiliation(s)
- Chetram Deochand
- Liver Research Center, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA.,Divisions of Gastroenterology, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA.,Department of Medicine, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
| | - Ming Tong
- Liver Research Center, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA.,Divisions of Gastroenterology, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA.,Department of Medicine, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
| | - Amit R Agarwal
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, USA
| | - Enrique Cadenas
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, USA
| | - Suzanne M de la Monte
- Liver Research Center, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA.,Divisions of Gastroenterology, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA.,Divisions of Neuropathology, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA.,Department of Medicine, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA.,Department of Pathology, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA.,Department of Neurology, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA.,Department of Neurosurgery, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
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Nolan JH, Wright CE. Evidence of Impaired Glucose Tolerance and Insulin Resistance in Patients With Alzheimer's Disease. CURRENT DIRECTIONS IN PSYCHOLOGICAL SCIENCE 2016. [DOI: 10.1111/1467-8721.00126] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Alzheimer's disease (AD) and diabetes rarely occur together, a finding that provides a possible clue as to the development of AD. Abnormal glucose metabolism is not limited to diabetes, but also can include impaired glucose tolerance, insulin resistance, and hyperinsulinemia. AD patients have significantly varying insulin levels after drinking sugared sodas and thus may be classified as insulin resistant. After reviewing the literature on impaired glucose tolerance and insulin production in AD, we present several hypotheses as possible explanations for the relationship between insulin resistance and AD. Finally, we suggest future studies, including studies on use of thiazolidinediones (currently used in the treatment of diabetes) in AD.
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Affiliation(s)
- Jennifer H. Nolan
- Department of Cognitive Science, University of California, Irvine, California
| | - Charles E. Wright
- Department of Cognitive Science, University of California, Irvine, California
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Yu R, Deochand C, Krotow A, Leão R, Tong M, Agarwal AR, Cadenas E, de la Monte SM. Tobacco Smoke-Induced Brain White Matter Myelin Dysfunction: Potential Co-Factor Role of Smoking in Neurodegeneration. J Alzheimers Dis 2016; 50:133-48. [PMID: 26639972 PMCID: PMC5577392 DOI: 10.3233/jad-150751] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND Meta-analysis studies showed that smokers have increased risk for developing Alzheimer's disease (AD) compared with non-smokers, and neuroimaging studies revealed that smoking damages white matter structural integrity. OBJECTIVE The present study characterizes the effects of side-stream (second hand) cigarette smoke (CS) exposures on the expression of genes that regulate oligodendrocyte myelin-synthesis, maturation, and maintenance and neuroglial functions. METHODS Adult male A/J mice were exposed to air (8 weeks; A8), CS (4 or 8 weeks; CS4, CS8), or CS8 followed by 2 weeks recovery (CS8 + R). The frontal lobes were used for histology and qRT-PCR analysis. RESULTS Luxol fast blue, Hematoxylin and Eosin stained histological sections revealed CS-associated reductions in myelin staining intensity and narrowing of the corpus callosum. CS exposures broadly decreased mRNA levels of immature and mature oligodendrocyte myelin-associated, neuroglial, and oligodendrocyte-related transcription factors. These effects were more prominent in the CS8 compared with CS4 group, suggesting that molecular abnormalities linked to white matter atrophy and myelin loss worsen with duration of CS exposure. Recovery normalized or upregulated less than 25% of the suppressed genes; in most cases, inhibition of gene expression was either sustained or exacerbated. CONCLUSION CS exposures broadly inhibit expression of genes needed for myelin synthesis and maintenance. These adverse effects often were not reversed by short-term CS withdrawal. The results support the hypothesis that smoking contributes to white matter degeneration, and therefore could be a key risk factor for a number of neurodegenerative diseases, including AD.
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Affiliation(s)
- Rosa Yu
- Liver Research Center, Divisions of Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
- Gastroenterology and Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
- Medicine, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
| | - Chetram Deochand
- Liver Research Center, Divisions of Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
- Gastroenterology and Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
- Medicine, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
- Molecular Pharmacology and Physiology Graduate Program at Brown University, Providence, RI, USA
| | - Alexander Krotow
- Molecular Pharmacology and Physiology Graduate Program at Brown University, Providence, RI, USA
| | - Raiane Leão
- Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Ming Tong
- Liver Research Center, Divisions of Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
- Gastroenterology and Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
- Medicine, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
| | - Amit R. Agarwal
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, USA
| | - Enrique Cadenas
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, USA
| | - Suzanne M. de la Monte
- Liver Research Center, Divisions of Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
- Gastroenterology and Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
- Neuropathology, and Departments of Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
- Medicine, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
- Pathology, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
- Neurology, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
- Neurosurgery, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
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Tong M, Yu R, Deochand C, de la Monte SM. Differential Contributions of Alcohol and the Nicotine-Derived Nitrosamine Ketone (NNK) to Insulin and Insulin-Like Growth Factor Resistance in the Adolescent Rat Brain. Alcohol Alcohol 2015; 50:670-9. [PMID: 26373814 DOI: 10.1093/alcalc/agv101] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Accepted: 08/17/2015] [Indexed: 12/11/2022] Open
Abstract
AIMS Since epidemiologic studies suggest that tobacco smoke toxins, e.g. the nicotine-derived nitrosamine ketone (NNK) tobacco-specific nitrosamine, can be a co-factor in alcohol-related brain disease (ARBD), we examined the independent and additive effects of alcohol and NNK exposures on spatial learning/memory, and brain insulin/IGF signaling, neuronal function and oxidative stress. METHODS Adolescent Long Evans rats were fed liquid diets containing 0 or 26% caloric ethanol for 8 weeks. During weeks 3-8, rats were treated with i.p. NNK (2 mg/kg, 3×/week) or saline. In weeks 7-8, ethanol groups were binge-administered ethanol (2 g/kg; 3×/week). In week 8, at 12 weeks of age, rats were subjected to Morris Water Maze tests. Temporal lobes were used to assess molecular indices of insulin/IGF resistance, oxidative stress and neuronal function. RESULTS Ethanol and NNK impaired spatial learning, and NNK ± ethanol impaired memory. Linear trend analysis demonstrated worsening performance from control to ethanol, to NNK, and then ethanol + NNK. Ethanol ± NNK, caused brain atrophy, inhibited insulin signaling through the insulin receptor and Akt, activated GSK-3β, increased protein carbonyl and 3-nitrotyrosine, and reduced acetylcholinesterase. NNK increased NTyr. Ethanol + NNK had synergistic stimulatory effects on 8-iso-PGF-2α, inhibitory effects on p-p70S6K, tau and p-tau and trend effects on insulin-like growth factor type 1 (IGF-1) receptor expression and phosphorylation. CONCLUSIONS Ethanol, NNK and combined ethanol + NNK exposures that begin in adolescence impair spatial learning and memory in young adults. The ethanol and/or NNK exposures differentially impair insulin/IGF signaling through neuronal growth, survival and plasticity pathways, increase cellular injury and oxidative stress and reduce expression of critical proteins needed for neuronal function.
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Affiliation(s)
- Ming Tong
- Department of Medicine, Division of Gastroenterology, and the Liver Research Center, Rhode Island Hospital, Providence, RI, USA Warren Alpert Medical School of Brown University, Providence, RI, USA
| | - Rosa Yu
- Departments of Pathology and Neurology, and the Division of Neuropathology, Rhode Island Hospital, Providence, RI, USA
| | - Chetram Deochand
- Biotechnology Graduate Program, Brown University, Providence, RI, USA
| | - Suzanne M de la Monte
- Department of Medicine, Division of Gastroenterology, and the Liver Research Center, Rhode Island Hospital, Providence, RI, USA Warren Alpert Medical School of Brown University, Providence, RI, USA Departments of Pathology and Neurology, and the Division of Neuropathology, Rhode Island Hospital, Providence, RI, USA
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Nine-month follow-up of the insulin receptor signalling cascade in the brain of streptozotocin rat model of sporadic Alzheimer's disease. J Neural Transm (Vienna) 2014; 122:565-76. [PMID: 25503661 DOI: 10.1007/s00702-014-1323-y] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Accepted: 10/01/2014] [Indexed: 12/21/2022]
Abstract
Sporadic Alzheimer disease (sAD) is associated with impairment of insulin receptor (IR) signalling in the brain. Rats used to model sAD develop insulin-resistant brain state following intracerebroventricular treatment with a betacytotoxic drug streptozotocin (STZ-icv). Brain IR signalling has been explored usually at only one time point in periods ≤3 months after the STZ-icv administration. We have investigated insulin signalling in the rat hippocampus at five time points in periods ≤9 months after STZ-icv treatment. Male Wistar rats were given vehicle (control)- or STZ (3 mg/kg)-icv injection and killed 0.5, 1, 3, 6 and 9 months afterwards. Insulin-1 (Ins-1), IR, phospho- and total (p/t)-glycogen synthase kinase 3-β (GSK-3β), p/t-tau and insulin degrading enzyme (IDE) mRNA and/or protein were measured. Acute upregulation of tau and IR mRNA (p < 0.05) was followed by a pronounced downregulation of Ins-1, IR and IDE mRNA (p < 0.05) in the course of time. Acute decrement in p/t-tau and p/t-GSK-3β ratios (p < 0.05) was followed by increment in both ratios (3-6 months, p < 0.05) after which p/t-tau ratio demonstrated a steep rise and p/t-GSK-3β ratio a steep fall up to 9 months (p < 0.05). Acute decline in IDE and IR expression (p < 0.05) was followed by a slow progression of the former and a slow recovery of the latter in 3-9 months. Results indicate a biphasic pattern in time dependency of onset and progression of changes in brain insulin signalling of STZ-icv model (partly reversible acute toxicity and chronic AD-like changes) which should be considered when using this model as a tool in translational sAD research.
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Li M, Chen L, Lee DHS, Yu LC, Zhang Y. The role of intracellular amyloid beta in Alzheimer's disease. Prog Neurobiol 2007; 83:131-9. [PMID: 17889422 DOI: 10.1016/j.pneurobio.2007.08.002] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2007] [Revised: 06/16/2007] [Accepted: 08/03/2007] [Indexed: 01/05/2023]
Abstract
Extracellular amyloid beta (Abeta) that confers neurotoxicity and modulates synaptic plasticity and memory function has been central to the amyloid hypothesis of Alzheimer's disease (AD) pathology. Like many other misfolded proteins identified in neurodegenerative disorders, Abeta also accumulates inside the AD neurons. This intracellular Abeta affects a variety of cellular physiology from protein degradation, axonal transport, autophagy to apoptosis, further documenting the role of Abeta in AD. Therapeutics targeting intracellular Abeta could be effective treatment for AD.
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Affiliation(s)
- Meng Li
- Laboratory of Neurobiology and State Key Laboratory of Biomembrane and Membrane Biotechnology, College of Life Sciences, Peking University, Beijing 100871, China
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Heidrich A, Rösler M. Milameline: Nonselective, Partial Muscarinic Receptor Agonist for the Treatment of Alzheimer's Disease? CNS DRUG REVIEWS 2006. [DOI: 10.1111/j.1527-3458.1999.tb00092.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Doré S, Bastianetto S, Kar S, Quirion R. Protective and rescuing abilities of IGF-I and some putative free radical scavengers against beta-amyloid-inducing toxicity in neurons. Ann N Y Acad Sci 2000; 890:356-64. [PMID: 10668442 DOI: 10.1111/j.1749-6632.1999.tb08015.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
beta-Amyloid (A beta) peptides are most likely involved in the neurodegenerative process occurring in Alzheimer's Disease (AD) and are enriched in senile plaques. The mechanisms of A beta toxicity are not clear but likely involve free radicals and apoptosis. Much interest is currently aiming at developing effective approaches to block A beta toxicity in order to slow down disease progression. In that context, we are particularly interested in studying the role of insulin-like growth factors, particularly IGF-I and purported free radical scavengers including a Gingko biloba extract (EGb761) as blocker of A beta toxicity in a simple in vitro model of hippocampal primary cultures. We observed that both IGF-I and EGb761 are unique in that they are able not only to protect but even to rescue neurons against A beta toxicity. These results are summarized here and possible mechanisms of action are discussed to explain the protective properties of these two classes of agents.
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Affiliation(s)
- S Doré
- Douglas Hospital Research Center, McGill University, Montreal, Quebec, Canada
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Luo JJ, Wallace W, Riccioni T, Ingram DK, Roth GS, Kusiak JW. Death of PC12 cells and hippocampal neurons induced by adenoviral-mediated FAD human amyloid precursor protein gene expression. J Neurosci Res 1999; 55:629-42. [PMID: 10082085 DOI: 10.1002/(sici)1097-4547(19990301)55:5<629::aid-jnr10>3.0.co;2-y] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
We used adenoviral-mediated gene transfer of human amyloid precursor proteins (h-APPs) to evaluate the role of various h-APPs in causing neuronal cell death. We were able to infect PC12 cells with very high efficiency because approximately 90% of the cells were cytochemically positive for beta-galactosidase activity when an adenoviral vector containing LacZ cDNA was used to infect cells. Cells infected with adenovirus containing h-APP cDNA showed high-level transcription and expression of h-APP as measured by reverse transcriptase-polymerase chain reaction and Western immunoblot analyses, respectively. Intracellular and extracellular levels of h-APP were elevated approximately 17-and 24-fold in cultures infected with recombinant adenovirus containing wild-type mutant and 13- and 17-fold with V642F mutant. No elevation in h-APP was seen in cultures infected with antisense h-APP or null adenovirus. H-APP levels were maximal 3 days after infection. Overexpression of V642F mutant h-APP in PC12 cells and hippocampal neurons resulted in about a twofold increase in death compared with overexpression of wild-type h-APP. These results demonstrate the usefulness of recombinant adenoviral mediated gene transfer in cell culture studies and suggest that overexpression of a familial Alzheimer's disease mutant APP may be toxic to neuronal cells.
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Affiliation(s)
- J J Luo
- Molecular Neurobiology Unit, Laboratory of Biological Chemistry, National Institute on Aging, Baltimore, Maryland 21224, USA.
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Affiliation(s)
- A Robles
- Division of Neurology, Complejo Hospitalario Universitario de Santiago, Santiago de Compostela, Spain
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Blanchard JG, Duncan PM. Effect of combinations of insulin, glucose and scopolamine on radial arm maze performance. Pharmacol Biochem Behav 1997; 58:209-14. [PMID: 9264093 DOI: 10.1016/s0091-3057(97)00064-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Previous research has shown that glucose is an effective agent in facilitating memory performance and in attenuating scopolamine-induced amnesia. Although insulin has not been shown to facilitate unimpaired memory, a previous study has demonstrated that insulin can also attenuate scopolamine-degraded memory. The present study was designed to determine how different combinations of insulin, glucose and scopolamine affect memory. It involved nine rats whose memory was assessed through performance in a win-shift radial arm maze task under different drug treatments. A 2 x 2 x 2 (insulin x glucose x scopolamine) within-subjects design with a 5-h drug test interval was employed. Scopolamine disrupted memory performance, and both glucose and insulin counteracted this disruption. Combining the glucose and insulin treatments did not increase their ability to attenuate scopolamine deficits but slightly decreased this effect. Glucose tended to enhance memory, even in the absence of scopolamine, whereas insulin had no effect on memory in the absence of scopolamine. Blood glucose levels were measured and did not indicate changes caused by drug treatments. The memory effects may have been due to the acetylcholine-agonist actions of glucose and insulin, an interpretation consistent with previous research findings.
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Affiliation(s)
- J G Blanchard
- Department of Psychology, Old Dominion University, Norfolk, VA 23529-0267, USA
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Doré S, Kar S, Quirion R. Insulin-like growth factor I protects and rescues hippocampal neurons against beta-amyloid- and human amylin-induced toxicity. Proc Natl Acad Sci U S A 1997; 94:4772-7. [PMID: 9114067 PMCID: PMC20800 DOI: 10.1073/pnas.94.9.4772] [Citation(s) in RCA: 270] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/1997] [Accepted: 02/24/1997] [Indexed: 02/04/2023] Open
Abstract
Insulin-like growth factors (IGF-I and IGF-II) are well known trophic factors and their specific receptors are uniquely distributed throughout the brain, being especially concentrated in the hippocampal formation. IGFs possess neurotrophic activities in the hippocampus, an area severely affected in Alzheimer disease. These data, together with the evidence that beta-amyloid (Abeta)-derived peptides likely play an important role in the neurodegenerative process observed in Alzheimer disease, led us to investigate if IGFs could be neuroprotective to hippocampal neurons against toxicity induced by amyloidogenic derivatives. Exposure of rat primary hippocampal neurons to different concentrations of Abeta25-35, Abeta1-40, Abeta1-42, and human amylin produced marked toxicity, while similar concentrations of two control Abeta peptides-reverse (Abeta40-1) and scrambled sequence (Abeta25-35)-and rat amylin failed to exhibit any significant effect on neuronal survival. IGF-I (10-100 nM) significantly protected hippocampal neurons against neurotoxicity induced by Abeta derivatives and human amylin. The homolog IGF-II was also effective although less potent than IGF-I suggesting the involvement of a typical IGF-I receptor in the observed neuroprotective effect. Most interestingly, IGF-I (10-100 nM) was even able to rescue neurons pre-exposed (up to 4 days) to amyloidogenic peptides. Other neurotrophic factors are reported to lack such rescuing abilities. These results suggest that IGF-I may have unique properties as a potent neuroprotective and neurorescuing agent against amyloid-related neurotoxicity.
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Affiliation(s)
- S Doré
- Douglas Hospital Research Centre, Department of Psychiatry, McGill University, Montreal, PQ Canada, H4H 1R3
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15
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Münch G, Thome J, Foley P, Schinzel R, Riederer P. Advanced glycation endproducts in ageing and Alzheimer's disease. BRAIN RESEARCH. BRAIN RESEARCH REVIEWS 1997; 23:134-43. [PMID: 9063589 DOI: 10.1016/s0165-0173(96)00016-1] [Citation(s) in RCA: 213] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Accumulation of advanced glycation endproducts (AGE) in the brain is a feature of ageing and degeneration, especially in Alzheimer's disease (AD). Increased AGE levels explain many of the neuropathological and biochemical features of AD such as extensive protein crosslinking (beta-amyloid and MAP-tau), oxidative stress and neuronal cell death. Oxidative stress and AGEs initiate a positive feedback loop, where normal age-related changes develop into a pathophysiological cascade. Combined intervention using antioxidants, metal chelators, anti-inflammatory drugs and AGE-inhibitors may be a promising neuroprotective strategy.
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Affiliation(s)
- G Münch
- Physiological Chemistry I, Theodor-Boveri-Institut (Biozentrum), Würzburg, Germany.
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16
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Abstract
Numerous studies indicate that aberrant amyloid precursor protein metabolism, elevated peroxidative damage, depressed energy metabolism and altered calcium homeostasis are four pivotal deleterious factors in the pathogenesis of Alzheimer's disease. Cumulative evidence further suggests that these four factors are intimately interrelated, forming a deleterious network. Based on this new concept of 'deleterious network', a unifying hypothesis-the deleterious network hypothesis of Alzheimer's disease-is proposed. The main ideas of the hypothesis are delineated as follows: increases in free radical damage, alterations in amyloid precursor protein metabolism, impairment of energy metabolism and abnormalities of calcium homeostasis are four cornerstones of a deleterious network. Various risk factors of Alzheimer's disease can triger the network by promoting the occurrence of one of these key components, resulting in the biological abnormalities of Alzheimer's disease. Based on this new theory, a majority of the important observations about Alzheimer's disease can be explained consistently and succinctly.
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Affiliation(s)
- W Ying
- Department of Physiology, School of Medicine, University of New Mexico, Albuquerque 87131, USA
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Davis JN, Hunnicutt EJ, Chisholm JC. A mitochondrial bottleneck hypothesis of Alzheimer's disease. ACTA ACUST UNITED AC 1995; 1:240-7. [PMID: 17607886 DOI: 10.1016/s1357-4310(95)91532-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Alzheimer's disease, in its early onset familial form, is known to be a heterogeneous disorder. This suggests that the different degenerative mechanisms, initiated by different genetic causes and ending in the shared phenotype of the disease, should intersect at some point in the degenerative cascade to form a 'bottleneck' from which the pathological features that are common to each of the genetic forms emerge. A growing body of evidence suggests that disturbances of energy metabolism may play a fundamental role in the onset and progression of Alzheimer's disease. In light of this, we propose a 'mitochondrial bottleneck hypothesis', which unifies the various forms of the disease in which different causes lead to the disorder via disturbances of mitochondrial function. The characterization of such a bottleneck would present a unique target for therapeutic intervention because it would be the earliest point in a neurodegenerative cascade shared by all forms of Alzheimer's disease, independent of cause.
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Affiliation(s)
- J N Davis
- Institute for Dementia Research, Bayer Corporation, West Haven, CT 06516, USA
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