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Nguyen TP, Priami C, Caberlotto L. Novel drug target identification for the treatment of dementia using multi-relational association mining. Sci Rep 2015; 5:11104. [PMID: 26154857 PMCID: PMC4495601 DOI: 10.1038/srep11104] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Accepted: 05/13/2015] [Indexed: 12/12/2022] Open
Abstract
Dementia is a neurodegenerative condition of the brain in which there is a progressive and permanent loss of cognitive and mental performance. Despite the fact that the number of people with dementia worldwide is steadily increasing and regardless of the advances in the molecular characterization of the disease, current medical treatments for dementia are purely symptomatic and hardly effective. We present a novel multi-relational association mining method that integrates the huge amount of scientific data accumulated in recent years to predict potential novel targets for innovative therapeutic treatment of dementia. Owing to the ability of processing large volumes of heterogeneous data, our method achieves a high performance and predicts numerous drug targets including several serine threonine kinase and a G-protein coupled receptor. The predicted drug targets are mainly functionally related to metabolism, cell surface receptor signaling pathways, immune response, apoptosis, and long-term memory. Among the highly represented kinase family and among the G-protein coupled receptors, DLG4 (PSD-95), and the bradikynin receptor 2 are highlighted also for their proposed role in memory and cognition, as described in previous studies. These novel putative targets hold promises for the development of novel therapeutic approaches for the treatment of dementia.
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Affiliation(s)
- Thanh-Phuong Nguyen
- The Microsoft Research, University of Trento Centre for Computational Systems Biology (COSBI), Piazza Manifattura 1, 38068, Rovereto, Italy
- Life Sciences Research Unit, University of Luxembourg, 162 A, avenue de la Faïencerie, L-1511 Luxembourg
| | - Corrado Priami
- The Microsoft Research, University of Trento Centre for Computational Systems Biology (COSBI), Piazza Manifattura 1, 38068, Rovereto, Italy
- Department of Mathematics, University of Trento, Via Sommarive, 14-38123 Povo, Italy
| | - Laura Caberlotto
- The Microsoft Research, University of Trento Centre for Computational Systems Biology (COSBI), Piazza Manifattura 1, 38068, Rovereto, Italy
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Bedse G, Di Domenico F, Serviddio G, Cassano T. Aberrant insulin signaling in Alzheimer's disease: current knowledge. Front Neurosci 2015; 9:204. [PMID: 26136647 PMCID: PMC4468388 DOI: 10.3389/fnins.2015.00204] [Citation(s) in RCA: 196] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Accepted: 05/22/2015] [Indexed: 12/18/2022] Open
Abstract
Alzheimer's disease (AD) is the most common form of dementia affecting elderly people. AD is a multifaceted pathology characterized by accumulation of extracellular neuritic plaques, intracellular neurofibrillary tangles (NFTs) and neuronal loss mainly in the cortex and hippocampus. AD etiology appears to be linked to a multitude of mechanisms that have not been yet completely elucidated. For long time, it was considered that insulin signaling has only peripheral actions but now it is widely accepted that insulin has neuromodulatory actions in the brain. Insulin signaling is involved in numerous brain functions including cognition and memory that are impaired in AD. Recent studies suggest that AD may be linked to brain insulin resistance and patients with diabetes have an increased risk of developing AD compared to healthy individuals. Indeed insulin resistance, increased inflammation and impaired metabolism are key pathological features of both AD and diabetes. However, the precise mechanisms involved in the development of AD in patients with diabetes are not yet fully understood. In this review we will discuss the role played by aberrant brain insulin signaling in AD. In detail, we will focus on the role of insulin signaling in the deposition of neuritic plaques and intracellular NFTs. Considering that insulin mitigates beta-amyloid deposition and phosphorylation of tau, pharmacological strategies restoring brain insulin signaling, such as intranasal delivery of insulin, could have significant therapeutic potential in AD treatment.
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Affiliation(s)
- Gaurav Bedse
- Department of Physiology and Pharmacology "V. Erspamer," Sapienza University of Rome Rome, Italy ; Department of Biochemical Sciences, Sapienza University of Rome Rome, Italy
| | - Fabio Di Domenico
- Department of Biochemical Sciences, Sapienza University of Rome Rome, Italy
| | - Gaetano Serviddio
- Department of Medical and Surgical Sciences, University of Foggia Foggia, Italy
| | - Tommaso Cassano
- Department of Clinical and Experimental Medicine, University of Foggia Foggia, Italy
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Liu Z, Patil IY, Jiang T, Sancheti H, Walsh JP, Stiles BL, Yin F, Cadenas E. High-fat diet induces hepatic insulin resistance and impairment of synaptic plasticity. PLoS One 2015; 10:e0128274. [PMID: 26023930 PMCID: PMC4449222 DOI: 10.1371/journal.pone.0128274] [Citation(s) in RCA: 143] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Accepted: 04/23/2015] [Indexed: 01/07/2023] Open
Abstract
High-fat diet (HFD)-induced obesity is associated with insulin resistance, which may affect brain synaptic plasticity through impairment of insulin-sensitive processes underlying neuronal survival, learning, and memory. The experimental model consisted of 3 month-old C57BL/6J mice fed either a normal chow diet (control group) or a HFD (60% of calorie from fat; HFD group) for 12 weeks. This model was characterized as a function of time in terms of body weight, fasting blood glucose and insulin levels, HOMA-IR values, and plasma triglycerides. IRS-1/Akt pathway was assessed in primary hepatocytes and brain homogenates. The effect of HFD in brain was assessed by electrophysiology, input/output responses and long-term potentiation. HFD-fed mice exhibited a significant increase in body weight, higher fasting glucose- and insulin levels in plasma, lower glucose tolerance, and higher HOMA-IR values. In liver, HFD elicited (a) a significant decrease of insulin receptor substrate (IRS-1) phosphorylation on Tyr608 and increase of Ser307 phosphorylation, indicative of IRS-1 inactivation; (b) these changes were accompanied by inflammatory responses in terms of increases in the expression of NFκB and iNOS and activation of the MAP kinases p38 and JNK; (c) primary hepatocytes from mice fed a HFD showed decreased cellular oxygen consumption rates (indicative of mitochondrial functional impairment); this can be ascribed partly to a decreased expression of PGC1α and mitochondrial biogenesis. In brain, HFD feeding elicited (a) an inactivation of the IRS-1 and, consequentially, (b) a decreased expression and plasma membrane localization of the insulin-sensitive neuronal glucose transporters GLUT3/GLUT4; (c) a suppression of the ERK/CREB pathway, and (d) a substantial decrease in long-term potentiation in the CA1 region of hippocampus (indicative of impaired synaptic plasticity). It may be surmised that 12 weeks fed with HFD induce a systemic insulin resistance that impacts profoundly on brain activity, i.e., synaptic plasticity.
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Affiliation(s)
- Zhigang Liu
- Pharmacology & Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, 90089, United States of America
- College of Food Science and Engineering, Northwest A&F University, Yangling, China
| | - Ishan Y. Patil
- Pharmacology & Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, 90089, United States of America
| | - Tianyi Jiang
- Pharmacology & Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, 90089, United States of America
| | - Harsh Sancheti
- Pharmacology & Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, 90089, United States of America
| | - John P. Walsh
- Davis School of Gerontology and Program in Neuroscience, University of Southern California, Los Angeles, CA, 90089, United States of America
| | - Bangyan L. Stiles
- Pharmacology & Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, 90089, United States of America
| | - Fei Yin
- Pharmacology & Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, 90089, United States of America
| | - Enrique Cadenas
- Pharmacology & Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, 90089, United States of America
- * E-mail:
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de la Monte SM. Type 3 diabetes is sporadic Alzheimer׳s disease: mini-review. Eur Neuropsychopharmacol 2014; 24:1954-60. [PMID: 25088942 PMCID: PMC4444430 DOI: 10.1016/j.euroneuro.2014.06.008] [Citation(s) in RCA: 222] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Accepted: 06/20/2014] [Indexed: 01/16/2023]
Abstract
Alzheimer׳s disease (AD) is the most common cause of dementia in North America. Growing evidence supports the concept that AD is a metabolic disease mediated by impairments in brain insulin responsiveness, glucose utilization, and energy metabolism, which lead to increased oxidative stress, inflammation, and worsening of insulin resistance. In addition, metabolic derangements directly contribute to the structural, functional, molecular, and biochemical abnormalities that characterize AD, including neuronal loss, synaptic disconnection, tau hyperphosphorylation, and amyloid-beta accumulation. Because the fundamental abnormalities in AD represent effects of brain insulin resistance and deficiency, and the molecular and biochemical consequences overlap with Type 1 and Type 2 diabetes, we suggest the term "Type 3 diabetes" to account for the underlying abnormalities associated with AD-type neurodegeneration. In light of the rapid increases in sporadic AD prevalence rates and vastly expanded use of nitrites and nitrates in foods and agricultural products over the past 30-40 years, the potential role of nitrosamine exposures as mediators of Type 3 diabetes is discussed.
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Affiliation(s)
- Suzanne M de la Monte
- Departments of Medicine, Pathology, Neurology, and Neurosurgery, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, 55 Claverick Street, Room 419, Providence, RI 02903, USA.
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Alexaki A, Gupta SD, Majumder S, Kono M, Tuymetova G, Harmon JM, Dunn TM, Proia RL. Autophagy regulates sphingolipid levels in the liver. J Lipid Res 2014; 55:2521-31. [PMID: 25332431 DOI: 10.1194/jlr.m051862] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Sphingolipid levels are tightly regulated to maintain cellular homeostasis. During pathologic conditions such as in aging, inflammation, and metabolic and neurodegenerative diseases, levels of some sphingolipids, including the bioactive metabolite ceramide, are elevated. Sphingolipid metabolism has been linked to autophagy, a critical catabolic process in both normal cell function and disease; however, the in vivo relevance of the interaction is not well-understood. Here, we show that blocking autophagy in the liver by deletion of the Atg7 gene, which is essential for autophagosome formation, causes an increase in sphingolipid metabolites including ceramide. We also show that overexpression of serine palmitoyltransferase to elevate de novo sphingolipid biosynthesis induces autophagy in the liver. The results reveal autophagy as a process that limits excessive ceramide levels and that is induced by excessive elevation of de novo sphingolipid synthesis in the liver. Dysfunctional autophagy may be an underlying mechanism causing elevations in ceramide that may contribute to pathogenesis in diseases.
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Affiliation(s)
- Aikaterini Alexaki
- Genetics of Development and Disease Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Sita D Gupta
- Departments of Biochemistry Uniformed Services University of the Health Sciences, Bethesda, MD 20184
| | - Saurav Majumder
- Genetics of Development and Disease Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Mari Kono
- Genetics of Development and Disease Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Galina Tuymetova
- Genetics of Development and Disease Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Jeffrey M Harmon
- Molecular Biology and Pharmacology, Uniformed Services University of the Health Sciences, Bethesda, MD 20184
| | - Teresa M Dunn
- Departments of Biochemistry Uniformed Services University of the Health Sciences, Bethesda, MD 20184
| | - Richard L Proia
- Genetics of Development and Disease Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892
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Ferreira ST, Clarke JR, Bomfim TR, De Felice FG. Inflammation, defective insulin signaling, and neuronal dysfunction in Alzheimer's disease. Alzheimers Dement 2014; 10:S76-83. [PMID: 24529528 DOI: 10.1016/j.jalz.2013.12.010] [Citation(s) in RCA: 239] [Impact Index Per Article: 23.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Accepted: 12/05/2013] [Indexed: 02/06/2023]
Abstract
A link between Alzheimer's disease (AD) and metabolic disorders has been established, with patients with type 2 diabetes at increased risk of developing AD and vice versa. The incidence of metabolic disorders, including insulin resistance and type 2 diabetes is increasing at alarming rates worldwide, primarily as a result of poor lifestyle habits. In parallel, as the world population ages, the prevalence of AD, the most common form of dementia in the elderly, also increases. In addition to their epidemiologic and clinical association, mounting recent evidence indicates shared mechanisms of pathogenesis between metabolic disorders and AD. We discuss the concept that peripheral and central nervous system inflammation link the pathogenesis of AD and metabolic diseases. We also explore the contribution of brain inflammation to defective insulin signaling and neuronal dysfunction. Last, we review recent evidence indicating that targeting neuroinflammation may provide novel therapeutic avenues for AD.
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Affiliation(s)
- Sergio T Ferreira
- Institute of Medical Biochemistry Leopoldo de Meis, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
| | - Julia R Clarke
- Institute of Medical Biochemistry Leopoldo de Meis, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Theresa R Bomfim
- Institute of Medical Biochemistry Leopoldo de Meis, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Fernanda G De Felice
- Institute of Medical Biochemistry Leopoldo de Meis, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
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57
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De Felice FG, Ferreira ST. Inflammation, defective insulin signaling, and mitochondrial dysfunction as common molecular denominators connecting type 2 diabetes to Alzheimer disease. Diabetes 2014; 63:2262-72. [PMID: 24931033 DOI: 10.2337/db13-1954] [Citation(s) in RCA: 415] [Impact Index Per Article: 41.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
A growing body of evidence supports an intriguing clinical/epidemiological connection between Alzheimer disease (AD) and type 2 diabetes (T2D). T2D patients have significantly increased risk of developing AD and vice versa. Recent studies have begun to reveal common pathogenic mechanisms shared by AD and metabolic disorders, notably obesity and T2D. In T2D and obesity, low-grade chronic inflammation is a key mechanism leading to peripheral insulin resistance, which progressively causes tissue deterioration and overall health decline. In the brain, proinflammatory signaling was recently found to mediate impaired neuronal insulin signaling, synapse deterioration, and memory loss. Here, we review evidence indicating that inflammation, insulin resistance, and mitochondrial dysfunction are common features in AD and T2D. We further propose the hypothesis that dementia and its underlying neuronal dysfunction are exacerbated or driven by peripheral inflammation. Identification of central and peripheral inflammation as potential mediators of brain dysfunction in AD may lead to the development of effective treatments for this devastating disease.
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Affiliation(s)
- Fernanda G De Felice
- Institute of Medical Biochemistry Leopoldo de Meis, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Sergio T Ferreira
- Institute of Medical Biochemistry Leopoldo de Meis, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
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58
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Elevated risk of type 2 diabetes for development of Alzheimer disease: a key role for oxidative stress in brain. Biochim Biophys Acta Mol Basis Dis 2014; 1842:1693-706. [PMID: 24949886 DOI: 10.1016/j.bbadis.2014.06.010] [Citation(s) in RCA: 263] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2014] [Revised: 06/05/2014] [Accepted: 06/09/2014] [Indexed: 12/23/2022]
Abstract
Alzheimer disease (AD) is the most common form of dementia among the elderly and is characterized by progressive loss of memory and cognition. Epidemiological data show that the incidence of AD increases with age and doubles every 5 years after 65 years of age. From a neuropathological point of view, amyloid-β-peptide (Aβ) leads to senile plaques, which, together with hyperphosphorylated tau-based neurofibrillary tangles and synapse loss, are the principal pathological hallmarks of AD. Aβ is associated with the formation of reactive oxygen (ROS) and nitrogen (RNS) species, and induces calcium-dependent excitotoxicity, impairment of cellular respiration, and alteration of synaptic functions associated with learning and memory. Oxidative stress was found to be associated with type 2 diabetes mellitus (T2DM), which (i) represents another prevalent disease associated with obesity and often aging, and (ii) is considered to be a risk factor for AD development. T2DM is characterized by high blood glucose levels resulting from increased hepatic glucose production, impaired insulin production and peripheral insulin resistance, which close resemble to the brain insulin resistance observed in AD patients. Furthermore, growing evidence suggests that oxidative stress plays a pivotal role in the development of insulin resistance and vice versa. This review article provides molecular aspects and the pharmacological approaches from both preclinical and clinical data interpreted from the point of view of oxidative stress with the aim of highlighting progresses in this field.
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Pathological roles of ceramide and its metabolites in metabolic syndrome and Alzheimer's disease. Biochim Biophys Acta Mol Cell Biol Lipids 2014; 1841:793-8. [DOI: 10.1016/j.bbalip.2013.08.002] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2013] [Revised: 07/30/2013] [Accepted: 08/02/2013] [Indexed: 02/03/2023]
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Kwon B, Lee HK, Querfurth HW. Oleate prevents palmitate-induced mitochondrial dysfunction, insulin resistance and inflammatory signaling in neuronal cells. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2014; 1843:1402-13. [PMID: 24732014 DOI: 10.1016/j.bbamcr.2014.04.004] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2014] [Revised: 03/31/2014] [Accepted: 04/04/2014] [Indexed: 01/22/2023]
Abstract
Elevated circulating levels of saturated free fatty acids (sFFAs; e.g. palmitate) are known to provoke inflammatory responses and cause insulin resistance in peripheral tissue. By contrast, mono- or poly-unsaturated FFAs are protective against sFFAs. An excess of sFFAs in the brain circulation may also trigger neuroinflammation and insulin resistance, however the underlying signaling changes have not been clarified in neuronal cells. In the present study, we examined the effects of palmitate on mitochondrial function and viability as well as on intracellular insulin and nuclear factor-κB (NF-κB) signaling pathways in Neuro-2a and primary rat cortical neurons. We next tested whether oleate preconditioning has a protective effect against palmitate-induced toxicity. Palmitate induced both mitochondrial dysfunction and insulin resistance while promoting the phosphorylation of mitogen-activated protein kinases and nuclear translocation of NF-κB p65. Oleate pre-exposure and then removal was sufficient to completely block subsequent palmitate-induced intracellular signaling and metabolic derangements. Oleate also prevented ceramide-induced insulin resistance. Moreover, oleate stimulated ATP while decreasing mitochondrial superoxide productions. The latter were associated with increased levels of peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α). Inhibition of protein kinase A (PKA) attenuated the protective effect of oleate against palmitate, implicating PKA in the mechanism of oleate action. Oleate increased triglyceride and blocked palmitate-induced diacylglycerol accumulations. Oleate preconditioning was superior to docosahexaenoic acid (DHA) or linoleate in the protection of neuronal cells against palmitate- or ceramide-induced cytotoxicity. We conclude that oleate has beneficial properties against sFFA and ceramide models of insulin resistance-associated damage to neuronal cells.
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Affiliation(s)
- Bumsup Kwon
- Department of Neurology, Rhode Island Hospital, Warren Alpert Medical School of Brown University, Providence, RI 02903, USA
| | - Han-Kyu Lee
- Department of Neurology, Rhode Island Hospital, Warren Alpert Medical School of Brown University, Providence, RI 02903, USA
| | - Henry W Querfurth
- Department of Neurology, Rhode Island Hospital, Warren Alpert Medical School of Brown University, Providence, RI 02903, USA.
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Abstract
Epidemics of obesity, diabetes, nonalcoholic fatty liver disease, and cognitive impairment/Alzheimer disease have emerged over the past 3 to 4 decades. These diseases share in common target-organ insulin resistance with a constellation of molecular and biochemical abnormalities that lead to organ/tissue degeneration over time. This article discusses the fundamental links among these diseases and how peripheral organ insulin resistance diseases contribute to cognitive impairment and neurodegeneration. A future role of endocrinologists and diabetologists could be to provide integrative diagnostic and treatment approaches for this collection of diseases that seem to share pathophysiological and pathogenetic bases.
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Affiliation(s)
- Suzanne M de la Monte
- Department of Pathology (Neuropathology), Rhode Island Hospital, Warren Alpert Medical School of Brown University, Providence, RI, USA; Department of Neurology, Rhode Island Hospital, Warren Alpert Medical School of Brown University, Providence, RI, USA; Department of Neurosurgery, Rhode Island Hospital, Warren Alpert Medical School of Brown University, Providence, RI, USA; Department of Medicine, Rhode Island Hospital, Warren Alpert Medical School of Brown University, Providence, RI, USA.
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62
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de la Monte SM, Tong M. Brain metabolic dysfunction at the core of Alzheimer's disease. Biochem Pharmacol 2013; 88:548-59. [PMID: 24380887 DOI: 10.1016/j.bcp.2013.12.012] [Citation(s) in RCA: 315] [Impact Index Per Article: 28.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2013] [Revised: 12/16/2013] [Accepted: 12/16/2013] [Indexed: 02/06/2023]
Abstract
Growing evidence supports the concept that Alzheimer's disease (AD) is fundamentally a metabolic disease with molecular and biochemical features that correspond with diabetes mellitus and other peripheral insulin resistance disorders. Brain insulin/IGF resistance and its consequences can readily account for most of the structural and functional abnormalities in AD. However, disease pathogenesis is complicated by the fact that AD can occur as a separate disease process, or arise in association with systemic insulin resistance diseases, including diabetes, obesity, and non-alcoholic fatty liver disease. Whether primary or secondary in origin, brain insulin/IGF resistance initiates a cascade of neurodegeneration that is propagated by metabolic dysfunction, increased oxidative and ER stress, neuro-inflammation, impaired cell survival, and dysregulated lipid metabolism. These injurious processes compromise neuronal and glial functions, reduce neurotransmitter homeostasis, and cause toxic oligomeric pTau and (amyloid beta peptide of amyloid beta precursor protein) AβPP-Aβ fibrils and insoluble aggregates (neurofibrillary tangles and plaques) to accumulate in brain. AD progresses due to: (1) activation of a harmful positive feedback loop that progressively worsens the effects of insulin resistance; and (2) the formation of ROS- and RNS-related lipid, protein, and DNA adducts that permanently damage basic cellular and molecular functions. Epidemiologic data suggest that insulin resistance diseases, including AD, are exposure-related in etiology. Furthermore, experimental and lifestyle trend data suggest chronic low-level nitrosamine exposures are responsible. These concepts offer opportunities to discover and implement new treatments and devise preventive measures to conquer the AD and other insulin resistance disease epidemics.
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Affiliation(s)
- Suzanne M de la Monte
- Departments of Pathology (Neuropathology), Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA; Departments of Neurology, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA; Departments of Neurosurgery, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA; Departments of Medicine, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA.
| | - Ming Tong
- Departments of Medicine, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
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63
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de la Monte SM. Intranasal insulin therapy for cognitive impairment and neurodegeneration: current state of the art. Expert Opin Drug Deliv 2013; 10:1699-709. [PMID: 24215447 PMCID: PMC4551402 DOI: 10.1517/17425247.2013.856877] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
INTRODUCTION Growing evidence supports the concept that insulin resistance plays an important role in the pathogenesis of cognitive impairment and neurodegeneration, including in Alzheimer's disease (AD). The metabolic hypothesis has led to the development and utilization of insulin- and insulin agonist-based treatments. Therapeutic challenges faced include the ability to provide effective treatments that do not require repeated injections and also the ability to minimize the potentially hazardous off-target effects. AREAS COVERED This review covers the role of intranasal insulin therapy for cognitive impairment and neurodegeneration, particularly AD. The literature reviewed focuses on data published within the past 5 years as this field is evolving rapidly. The review provides evidence that brain insulin resistance is an important and early abnormality in AD, and that increasing brain supply and utilization of insulin improves cognition and memory. Emphasis was placed on discussing outcomes of clinical trials and interpreting discordant results to clarify the benefits and limitations of intranasal insulin therapy. EXPERT OPINION Intranasal insulin therapy can efficiently and directly target the brain to support energy metabolism, myelin maintenance, cell survival and neuronal plasticity, which begin to fail in the early stages of neurodegeneration. Efforts must continue toward increasing the safety, efficacy and specificity of intranasal insulin therapy.
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Affiliation(s)
- Suzanne M de la Monte
- Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Departments of Pathology (Neuropathology), Neurology, and Neurosurgery , Pierre Galletti Research Building, Claverick Street, Room 419, Providence, RI 02903 , USA +1 401 444 7364 ; +1 401 444 2939 ;
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64
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Tong M, Longato L, Ramirez T, Zabala V, Wands JR, de la Monte SM. Therapeutic reversal of chronic alcohol-related steatohepatitis with the ceramide inhibitor myriocin. Int J Exp Pathol 2013; 95:49-63. [PMID: 24456332 DOI: 10.1111/iep.12052] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2013] [Accepted: 08/18/2013] [Indexed: 12/13/2022] Open
Abstract
Alcohol-related liver disease (ALD) is associated with steatohepatitis and insulin resistance. Insulin resistance impairs growth and disrupts lipid metabolism in hepatocytes. Dysregulated lipid metabolism promotes ceramide accumulation and oxidative stress, leading to lipotoxic states that activate endoplasmic reticulum (ER) stress pathways and worsen inflammation and insulin resistance. In a rat model of chronic alcohol feeding, we characterized the effects of a ceramide inhibitor, myriocin, on the histopathological and ultrastructural features of steatohepatitis, and the biochemical and molecular indices of hepatic steatosis, insulin resistance and ER stress. Myriocin reduced the severity of alcohol-related steatohepatitis including the abundance and sizes of lipid droplets and mitochondria, inflammation and architectural disruption of the ER. In addition, myriocin-mediated reductions in hepatic lipid and ceramide levels were associated with constitutive enhancement of insulin signalling through the insulin receptor and IRS-2, reduced hepatic oxidative stress and modulation of ER stress signalling mechanisms. In conclusion, ceramide accumulation in liver mediates tissue injury, insulin resistance and lipotoxicity in ALD. Reducing hepatic ceramide levels can help restore the structural and functional integrity of the liver in chronic ALD due to amelioration of insulin resistance and ER stress. However, additional measures are needed to protect the liver from alcohol-induced necroinflammatory responses vis-à-vis continued alcohol abuse.
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Affiliation(s)
- Ming Tong
- Liver Research Center, Division of Gastroenterology, Department of Medicine, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
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Johansson P, Åberg D, Johansson JO, Mattsson N, Hansson O, Ahrén B, Isgaard J, Åberg ND, Blennow K, Zetterberg H, Wallin A, Svensson J. Serum but not cerebrospinal fluid levels of insulin-like growth factor-I (IGF-I) and IGF-binding protein-3 (IGFBP-3) are increased in Alzheimer's disease. Psychoneuroendocrinology 2013; 38:1729-37. [PMID: 23473966 DOI: 10.1016/j.psyneuen.2013.02.006] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2012] [Revised: 02/05/2013] [Accepted: 02/05/2013] [Indexed: 01/21/2023]
Abstract
BACKGROUND Although insulin-like growth factor-I (IGF-I) is of importance for the adult function of the central nervous system (CNS), little is known of the significance of IGF-I in cerebrospinal fluid (CSF) in relation to Alzheimer's disease (AD). METHODS A cross-sectional study of 60 consecutive patients under primary evaluation of cognitive impairment and 20 healthy controls. The patients had AD dementia or mild cognitive impairment (MCI) diagnosed with AD dementia upon follow-up (n=32), stable MCI (SMCI, n=13), or other dementias (n=15). IGF-I, IGF-binding protein-3 (IGFBP-3), and insulin were measured in serum and CSF. RESULTS Serum IGF-I level was increased in AD patients and in patients with other dementias compared to healthy controls (P=0.01 and P<0.05, respectively). Serum IGFBP-3 concentration was increased in AD and SMCI patients compared to controls (P=0.001 and P<0.05, respectively). CSF levels of IGF-I and IGFBP-3 as well as serum and CSF levels of insulin were similar in all study groups. In the total study population (n=80), serum levels of IGF-I and IGFBP-3 correlated negatively with CSF β-amyloid₁₋₄₂ (Aβ₁₋₄₂) level (r=-0.29, P=0.01 and r=-0.27, P=0.02, respectively) and in the AD patients (n=32), the increased CSF/serum IGF-I ratio correlated positively with the CSF level of phosphorylated tau protein (P-tau; r=0.42, P=0.02). CONCLUSION Patients with AD as well as other dementias had high levels of IGF-I in serum but not in CSF. In AD patients, the IGF-I system was associated with biomarkers of AD disease status.
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Affiliation(s)
- Per Johansson
- Department of Neuropsychiatry, Skaraborg Hospital, SE-521 85 Falköping, Sweden; Department of Internal Medicine, Sahlgrenska Academy, University of Gothenburg, SE-413 45 Gothenburg, Sweden
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Huang X, Withers BR, Dickson RC. Sphingolipids and lifespan regulation. Biochim Biophys Acta Mol Cell Biol Lipids 2013; 1841:657-64. [PMID: 23954556 DOI: 10.1016/j.bbalip.2013.08.006] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Revised: 08/01/2013] [Accepted: 08/06/2013] [Indexed: 02/08/2023]
Abstract
Diseases including cancer, type 2 diabetes, cardiovascular and immune dysfunction and neurodegeneration become more prevalent as we age, and combined with the increase in average human lifespan, place an ever increasing burden on the health care system. In this chapter we focus on finding ways of modulating sphingolipids to prevent the development of age-associated diseases or delay their onset, both of which could improve health in elderly, fragile people. Reducing the incidence of or delaying the onset of diseases of aging has blossomed in the past decade because of advances in understanding signal transduction pathways and cellular processes, especially in model organisms, that are largely conserved in most eukaryotes and that can be modulated to reduce signs of aging and increase health span. In model organisms such interventions must also increase lifespan to be considered significant, but this is not a requirement for use in humans. The most encouraging interventions in model organisms involve lowering the concentration of one or more sphingolipids so as to reduce the activity of key signaling pathways, one of the most promising being the Target of Rapamycin Complex 1 (TORC1) protein kinase pathway. Other potential ways in which modulating sphingolipids may contribute to improving the health profile of the elderly is by reducing oxidative stresses, inflammatory responses and growth factor signaling. Lastly, perhaps the most interesting way to modulate sphingolipids and promote longevity is by lowering the activity of serine palmitoyltransferase, the first enzyme in the de novo sphingolipid biosynthesis pathway. Available data in yeasts and rodents are encouraging and as we gain insights into molecular mechanisms the strategies for improving human health by modulating sphingolipids will become more apparent. This article is part of a Special Issue entitled New Frontiers in Sphingolipid Biology.
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Affiliation(s)
- Xinhe Huang
- Department of Molecular and Cellular Biochemistry and the Lucille Markey Cancer Center, University of Kentucky College of Medicine, 741 S. Limestone, Lexington, KY 40536, USA
| | - Bradley R Withers
- Department of Molecular and Cellular Biochemistry and the Lucille Markey Cancer Center, University of Kentucky College of Medicine, 741 S. Limestone, Lexington, KY 40536, USA
| | - Robert C Dickson
- Department of Molecular and Cellular Biochemistry and the Lucille Markey Cancer Center, University of Kentucky College of Medicine, 741 S. Limestone, Lexington, KY 40536, USA.
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Asle-Rousta M, Oryan S, Ahmadiani A, Rahnema M. Activation of sphingosine 1-phosphate receptor-1 by SEW2871 improves cognitive function in Alzheimer's disease model rats. EXCLI JOURNAL 2013; 12:449-61. [PMID: 26417237 PMCID: PMC4566907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Accepted: 04/18/2013] [Indexed: 11/26/2022]
Abstract
Sphingosine-1 phosphate (S1P) is involved in a variety of cellular processes via activation of S1P receptors (S1PRs; S1PR1 to S1PR5) that are highly expressed in the brain. It has been shown that the level of S1P is reduced in the brain of Alzheimer's disease (AD) patients. However, there is no study designed to evaluate the expression of S1PRs in AD brains. The objectives of the present work are (1) to examine the expression of S1PR1-3 in the hippocampus of beta amyloid (Aβ) 1-42 injected rats and (2) to clarify the effects of chronic S1PR1 activation on S1PR1-3 levels, spatial memory deficit and hippocampal damage in AD rats. SEW2871, the S1PR1 selective agonist, repeatedly was injected intraperitoneally during a period of two weeks. Upon Western Blot data bilateral intrahippocampal injection of Aβ1-42 decreased the expression of S1PR1 while increased S1PR2 level and did not affect that of S1PR3. We found that chronic administration of SEW2871 inhibited the reduction of S1PR1 expression and ameliorated spatial memory impairment in the Morris water maze task in rats. In addition, SEW2871 attenuated the Aβ1-42-induced hippocampal neuronal loss according to Nissl staining findings. Data in the current study highlights the importance of S1PR1 signaling pathway deregulation in AD development and suggests that activation of S1PR1 may represent a potential approach for developing new therapeutics to manage memory deficit and apoptosis associated with neurodegenerative disorders such as AD.
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Affiliation(s)
- Masoumeh Asle-Rousta
- Department of Biology, Science and Research Branch, Islamic Azad University, Tehran, Iran,*To whom correspondence should be addressed: Masoumeh Asle-Rousta, Department of Biology, Science and Research Branch, Islamic Azad University, Tehran, Iran; Tel: +98 9125606327, Fax: +98 2644231404, E-mail:
| | - Shahrbanoo Oryan
- Faculty of Biological Sciences, Kharazmi University, Tehran, Iran
| | - Abolhassan Ahmadiani
- Neuroscience Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran,Department of Pharmacology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Mehdi Rahnema
- Department of Biology, Faculty of Basic and Medical Sciences, Zanjan Branch, Islamic Azad University, Zanjan, Iran
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Saito M, Saito M. Involvement of sphingolipids in ethanol neurotoxicity in the developing brain. Brain Sci 2013; 3:670-703. [PMID: 24961420 PMCID: PMC4061845 DOI: 10.3390/brainsci3020670] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2013] [Revised: 03/30/2013] [Accepted: 04/12/2013] [Indexed: 12/16/2022] Open
Abstract
Ethanol-induced neuronal death during a sensitive period of brain development is considered one of the significant causes of fetal alcohol spectrum disorders (FASD). In rodent models, ethanol triggers robust apoptotic neurodegeneration during a period of active synaptogenesis that occurs around the first two postnatal weeks, equivalent to the third trimester in human fetuses. The ethanol-induced apoptosis is mitochondria-dependent, involving Bax and caspase-3 activation. Such apoptotic pathways are often mediated by sphingolipids, a class of bioactive lipids ubiquitously present in eukaryotic cellular membranes. While the central role of lipids in ethanol liver toxicity is well recognized, the involvement of sphingolipids in ethanol neurotoxicity is less explored despite mounting evidence of their importance in neuronal apoptosis. Nevertheless, recent studies indicate that ethanol-induced neuronal apoptosis in animal models of FASD is mediated or regulated by cellular sphingolipids, including via the pro-apoptotic action of ceramide and through the neuroprotective action of GM1 ganglioside. Such sphingolipid involvement in ethanol neurotoxicity in the developing brain may provide unique targets for therapeutic applications against FASD. Here we summarize findings describing the involvement of sphingolipids in ethanol-induced apoptosis and discuss the possibility that the combined action of various sphingolipids in mitochondria may control neuronal cell fate.
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Affiliation(s)
- Mariko Saito
- Division of Neurochemistry, Nathan S. Kline Institute for Psychiatric Research, 140 Old Orangeburg Rd., Orangeburg, NY 10962, USA.
| | - Mitsuo Saito
- Division of Analytical Psychopharmacology, Nathan S. Kline Institute for Psychiatric Research, 140 Old Orangeburg Rd., Orangeburg, NY 10962, USA.
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Asle-Rousta M, Kolahdooz Z, Oryan S, Ahmadiani A, Dargahi L. FTY720 (fingolimod) attenuates beta-amyloid peptide (Aβ42)-induced impairment of spatial learning and memory in rats. J Mol Neurosci 2013; 50:524-32. [PMID: 23435938 DOI: 10.1007/s12031-013-9979-6] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Accepted: 02/08/2013] [Indexed: 12/29/2022]
Abstract
Imbalanced lipid metabolism and increase in the ceramide-to-S1P ratio in the brain have been postulated to play a role in amyloidogenesis, neuroinflammatory reactions, and neuronal apoptosis in Alzheimer's disease (AD) pathology. FTY720, the immunomodulatory sphingosine 1-phosphate (S1P) analog, has recently gained interest because of its CNS-directed effects. In addition to its immunomodulatory functions in multiple sclerosis, FTY720 possesses anti-inflammatory and neuroprotective roles in different cerebral ischemia models. In the present study, we examined the effects of FTY720 in a rat model of AD. Memory deficit was induced by bilateral intrahippocampus injection of beta-amyloid peptide (Aβ(42)) and examined through the Morris water maze test. The extent of histological injury in the hippocampus and the activation of caspase-3 were determined respectively by Nissl staining and Western blotting. Chronic daily administration of FTY720 (1 mg/kg, i.p., 14 days) significantly attenuated the Aβ(42)-induced learning and memory impairment and prevented the hippocampus neuronal damage as well as caspase-3 activation. These data show for the first time that FTY720 has a beneficial effect in restoring memory loss in Aβ(42)-induced neurotoxicity and also suggest that S1P receptors and signaling pathways may provide a potential target for the treatment of AD.
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Affiliation(s)
- Masoumeh Asle-Rousta
- Neuroscience Research Center, Shahid Beheshti University of Medical Sciences, Evin, Tehran, 19615-1178, Iran
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Lee S, Tong M, Hang S, Deochand C, de la Monte S. CSF and Brain Indices of Insulin Resistance, Oxidative Stress and Neuro-Inflammation in Early versus Late Alzheimer's Disease. ACTA ACUST UNITED AC 2013; 3:128. [PMID: 25035815 PMCID: PMC4096626 DOI: 10.4172/2161-0460.1000128] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Alzheimer’s disease (AD) is characterized by progressive impairments in cognitive and behavioral functions with deficits in learning, memory and executive reasoning. Growing evidence points toward brain insulin and insulin-like growth factor (IGF) resistance-mediated metabolic derangements as critical etiologic factors in AD. This suggests that indices of insulin/IGF resistance and their consequences, i.e. oxidative stress, neuro-inflammation, and reduced neuronal plasticity, should be included in biomarker panels for AD. Herein, we examine a range of metabolic, inflammatory, stress, and neuronal plasticity related proteins in early AD, late AD, and aged control postmortem brain, postmortem ventricular fluid (VF), and clinical cerebrospinal fluid (CSF) samples. In AD brain, VF, and CSF samples the trends with respect to alterations in metabolic, neurotrophin, and stress indices were similar, but for pro-inflammatory cytokines, the patterns were discordant. With the greater severities of dementia and neurodegeneration, the differences from control were more pronounced for late AD (VF and brain) than early or moderate AD (brain, VF and CSF). The findings suggest that the inclusion of metabolic, neurotrophin, stress biomarkers in AβPP-Aβ+pTau CSF-based panels could provide more information about the status and progression of neurodegeneration, as well as aid in predicting progression from early- to late-stage AD. Furthermore, standardized multi-targeted molecular assays of neurodegeneration could help streamline postmortem diagnoses, including assessments of AD severity and pathology.
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Affiliation(s)
- Sarah Lee
- Department of Medicine, Rhode Island Hospital, Warren Alpert Medical School, Providence, RI, USA
| | - Ming Tong
- Department of Medicine, Rhode Island Hospital, Warren Alpert Medical School, Providence, RI, USA
| | - Steven Hang
- Department of Medicine, Warren Alpert Medical School, Providence, RI, USA
| | - Chetram Deochand
- Departments of Medicine, Rhode Island Hospital, Brown University, Providence, RI, USA
| | - Suzanne de la Monte
- Department of Medicine, Pathology (Neuropathology), Neurology and Neurosurgery, Rhode Island Hospital, Warren Alpert Medical School, Brown University, Providence, RI, USA
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Mielke MM, Haughey NJ. Could plasma sphingolipids be diagnostic or prognostic biomarkers for Alzheimer's disease? ACTA ACUST UNITED AC 2012; 7:525-536. [PMID: 23606909 DOI: 10.2217/clp.12.59] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Understanding the etiopathological processes of Alzheimer's disease (AD) in the preclinical and early clinical stages will be important in developing new therapeutic targets and biomarkers. There is growing consensus that nonamyloid targets will be necessary to reverse or slow AD progression. Lipidomic, metabolomic and targeted approaches have identified pathways and products of sphingolipid metabolism that are altered early in the course of AD and contribute to the neuropathological alterations associated with AD, including amyloid-β production, tau formation and neurodegeneration. In this article, we briefly review the current literature on the role of sphingolipids in the underlying pathophysiology of AD, and then discuss the current state of translating these findings to clinical populations and the potential utility of plasma sphingolipids as diagnostic and/or prognostic indicators of AD.
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Affiliation(s)
- Michelle M Mielke
- Division of Epidemiology, Department of Health Sciences Research, College of Medicine, Mayo Clinic, 200 First Street Southwest, Rochester, MN 55905, USA
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De La Monte SM. Metabolic derangements mediate cognitive impairment and Alzheimer's disease: role of peripheral insulin-resistance diseases. Panminerva Med 2012; 54:171-8. [PMID: 22801434 PMCID: PMC4537701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Herein, we review evidence that systemic insulin-resistance diseases linked to obesity, type 2 diabetes, and non-alcoholic steatohepatitis promote neurodegeneration. Insulin-resistance dysregulates lipid metabolism, which promotes ceramide accumulation with attendant inflammation and endoplasmic reticulum (ER) stress. Mechanistically, we propose that toxic ceramides generated in extra-CNS tissues, e.g. liver, get released into peripheral blood, and subsequently transit across the blood-brain barrier into the brain where they induce brain insulin-resistance, inflammation, and cell death (extrinsic pathway). These abnormalities establish or help propagate a cascade of neurodegeneration associated with increased ER stress and ceramide generation, which exacerbate brain insulin-resistance, cell death, myelin degeneration, and neuro-inflammation. The data suggest that a mal-signaling network mediated by toxic ceramides, ER stress, and insulin-resistance should be targeted to disrupt positive feedback loops that drive the AD neurodegeneration cascade.
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Affiliation(s)
- S M De La Monte
- Department of Neuropathology, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA.
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