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Abdalla MMI. Insulin resistance as the molecular link between diabetes and Alzheimer's disease. World J Diabetes 2024; 15:1430-1447. [DOI: 10.4239/wjd.v15.i7.1430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Revised: 04/08/2024] [Accepted: 05/06/2024] [Indexed: 07/08/2024] Open
Abstract
Diabetes mellitus (DM) and Alzheimer's disease (AD) are two major health concerns that have seen a rising prevalence worldwide. Recent studies have indicated a possible link between DM and an increased risk of developing AD. Insulin, while primarily known for its role in regulating blood sugar, also plays a vital role in protecting brain functions. Insulin resistance (IR), especially prevalent in type 2 diabetes, is believed to play a significant role in AD's development. When insulin signalling becomes dysfunctional, it can negatively affect various brain functions, making individuals more susceptible to AD's defining features, such as the buildup of beta-amyloid plaques and tau protein tangles. Emerging research suggests that addressing insulin-related issues might help reduce or even reverse the brain changes linked to AD. This review aims to explore the rela-tionship between DM and AD, with a focus on the role of IR. It also explores the molecular mechanisms by which IR might lead to brain changes and assesses current treatments that target IR. Understanding IR's role in the connection between DM and AD offers new possibilities for treatments and highlights the importance of continued research in this interdisciplinary field.
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Affiliation(s)
- Mona Mohamed Ibrahim Abdalla
- Department of Human Biology, School of Medicine, International Medical University, Bukit Jalil 57000, Kuala Lumpur, Malaysia
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2
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Sunna S, Bowen CA, Ramelow CC, Santiago JV, Kumar P, Rangaraju S. Advances in proteomic phenotyping of microglia in neurodegeneration. Proteomics 2023; 23:e2200183. [PMID: 37060300 PMCID: PMC10528430 DOI: 10.1002/pmic.202200183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 04/04/2023] [Accepted: 04/05/2023] [Indexed: 04/16/2023]
Abstract
Microglia are dynamic resident immune cells of the central nervous system (CNS) that sense, survey, and respond to changes in their environment. In disease states, microglia transform from homeostatic to diverse molecular phenotypic states that play complex and causal roles in neurologic disease pathogenesis, as evidenced by the identification of microglial genes as genetic risk factors for neurodegenerative disease. While advances in transcriptomic profiling of microglia from the CNS of humans and animal models have provided transformative insights, the transcriptome is only modestly reflective of the proteome. Proteomic profiling of microglia is therefore more likely to provide functionally and therapeutically relevant targets. In this review, we discuss molecular insights gained from transcriptomic studies of microglia in the context of Alzheimer's disease as a prototypic neurodegenerative disease, and highlight existing and emerging approaches for proteomic profiling of microglia derived from in vivo model systems and human brain.
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Affiliation(s)
- Sydney Sunna
- Department of Neurology, Emory University,201 Dowman Drive Atlanta Georgia, 30322, United States of America
- Center for Neurodegenerative Diseases, Emory University, Atlanta, GA 30322, USA
| | - Christine A. Bowen
- Department of Neurology, Emory University,201 Dowman Drive Atlanta Georgia, 30322, United States of America
- Center for Neurodegenerative Diseases, Emory University, Atlanta, GA 30322, USA
- Department of Biochemistry, Emory University, Atlanta, GA 30322, USA
| | - Christina C. Ramelow
- Department of Neurology, Emory University,201 Dowman Drive Atlanta Georgia, 30322, United States of America
- Center for Neurodegenerative Diseases, Emory University, Atlanta, GA 30322, USA
| | - Juliet V. Santiago
- Department of Neurology, Emory University,201 Dowman Drive Atlanta Georgia, 30322, United States of America
- Center for Neurodegenerative Diseases, Emory University, Atlanta, GA 30322, USA
| | - Prateek Kumar
- Department of Neurology, Emory University,201 Dowman Drive Atlanta Georgia, 30322, United States of America
- Center for Neurodegenerative Diseases, Emory University, Atlanta, GA 30322, USA
| | - Srikant Rangaraju
- Department of Neurology, Emory University,201 Dowman Drive Atlanta Georgia, 30322, United States of America
- Center for Neurodegenerative Diseases, Emory University, Atlanta, GA 30322, USA
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Michailidis M, Moraitou D, Tata DA, Kalinderi K, Papamitsou T, Papaliagkas V. Alzheimer's Disease as Type 3 Diabetes: Common Pathophysiological Mechanisms between Alzheimer's Disease and Type 2 Diabetes. Int J Mol Sci 2022; 23:2687. [PMID: 35269827 PMCID: PMC8910482 DOI: 10.3390/ijms23052687] [Citation(s) in RCA: 74] [Impact Index Per Article: 37.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Revised: 02/25/2022] [Accepted: 02/26/2022] [Indexed: 12/27/2022] Open
Abstract
Globally, the incidence of type 2 diabetes mellitus (T2DM) and Alzheimer's disease (AD) epidemics is increasing rapidly and has huge financial and emotional costs. The purpose of the current review article is to discuss the shared pathophysiological connections between AD and T2DM. Research findings are presented to underline the vital role that insulin plays in the brain's neurotransmitters, homeostasis of energy, as well as memory capacity. The findings of this review indicate the existence of a mechanistic interplay between AD pathogenesis with T2DM and, especially, disrupted insulin signaling. AD and T2DM are interlinked with insulin resistance, neuroinflammation, oxidative stress, advanced glycosylation end products (AGEs), mitochondrial dysfunction and metabolic syndrome. Beta-amyloid, tau protein and amylin can accumulate in T2DM and AD brains. Given that the T2DM patients are not routinely evaluated in terms of their cognitive status, they are rarely treated for cognitive impairment. Similarly, AD patients are not routinely evaluated for high levels of insulin or for T2DM. Studies suggesting AD as a metabolic disease caused by insulin resistance in the brain also offer strong support for the hypothesis that AD is a type 3 diabetes.
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Affiliation(s)
- Michalis Michailidis
- Laboratory of Psychology, School of Psychology, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece; (M.M.); (D.M.); (D.A.T.)
| | - Despina Moraitou
- Laboratory of Psychology, School of Psychology, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece; (M.M.); (D.M.); (D.A.T.)
| | - Despina A. Tata
- Laboratory of Psychology, School of Psychology, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece; (M.M.); (D.M.); (D.A.T.)
| | - Kallirhoe Kalinderi
- Laboratory of Medical Biology-Genetics, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece;
| | - Theodora Papamitsou
- Histology and Embryology Department, Faculty of Medicine, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece;
| | - Vasileios Papaliagkas
- Department of Biomedical Sciences, School of Health Sciences, International Hellenic University, 57400 Thessaloniki, Greece
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Zhou HL, Premont RT, Stamler JS. The manifold roles of protein S-nitrosylation in the life of insulin. Nat Rev Endocrinol 2022; 18:111-128. [PMID: 34789923 PMCID: PMC8889587 DOI: 10.1038/s41574-021-00583-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/08/2021] [Indexed: 02/04/2023]
Abstract
Insulin, which is released by pancreatic islet β-cells in response to elevated levels of glucose in the blood, is a critical regulator of metabolism. Insulin triggers the uptake of glucose and fatty acids into the liver, adipose tissue and muscle, and promotes the storage of these nutrients in the form of glycogen and lipids. Dysregulation of insulin synthesis, secretion, transport, degradation or signal transduction all cause failure to take up and store nutrients, resulting in type 1 diabetes mellitus, type 2 diabetes mellitus and metabolic dysfunction. In this Review, we make the case that insulin signalling is intimately coupled to protein S-nitrosylation, in which nitric oxide groups are conjugated to cysteine thiols to form S-nitrosothiols, within effectors of insulin action. We discuss the role of S-nitrosylation in the life cycle of insulin, from its synthesis and secretion in pancreatic β-cells, to its signalling and degradation in target tissues. Finally, we consider how aberrant S-nitrosylation contributes to metabolic diseases, including the roles of human genetic mutations and cellular events that alter S-nitrosylation of insulin-regulating proteins. Given the growing influence of S-nitrosylation in cellular metabolism, the field of metabolic signalling could benefit from renewed focus on S-nitrosylation in type 2 diabetes mellitus and insulin-related disorders.
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Affiliation(s)
- Hua-Lin Zhou
- Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH, USA
- Institute for Transformative Molecular Medicine, Case Western Reserve University School of Medicine, Cleveland, OH, USA
- Harrington Discovery Institute, University Hospitals Cleveland Medical Center, Cleveland, OH, USA
| | - Richard T Premont
- Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH, USA
- Institute for Transformative Molecular Medicine, Case Western Reserve University School of Medicine, Cleveland, OH, USA
- Harrington Discovery Institute, University Hospitals Cleveland Medical Center, Cleveland, OH, USA
| | - Jonathan S Stamler
- Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH, USA.
- Institute for Transformative Molecular Medicine, Case Western Reserve University School of Medicine, Cleveland, OH, USA.
- Harrington Discovery Institute, University Hospitals Cleveland Medical Center, Cleveland, OH, USA.
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Tong XW, Zhang YT, Yu ZW, Pu SD, Li X, Xu YX, Shan YY, Gao XY. Triglyceride Glucose Index is Related with the Risk of Mild Cognitive Impairment in Type 2 Diabetes. Diabetes Metab Syndr Obes 2022; 15:3577-3587. [PMID: 36426213 PMCID: PMC9680968 DOI: 10.2147/dmso.s389327] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Accepted: 11/04/2022] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND The triglyceride glucose (TyG) index reflects insulin resistance; the latter being associated with mild cognitive impairment (MCI). OBJECTIVE To investigate the clinical value of the TyG index to identify MCI in patients living with type 2 diabetes (T2D) using a cross-sectional study. METHODS This cross-sectional study was performed on 517 patients with T2D. The diagnosis of MCI was based on criteria established by the National Institute on Aging-Alzheimer's Association workgroup, and patients were divided into the MCI group and the normal cognitive function (NCF) group. The logistic regression analysis determines whether the TyG index is related to MCI. Subsequently, we constructed the receiver operating characteristic curve (ROC) and calculated the area under the curve (AUC). The nomogram model of the influence factor was established and verified. RESULTS Compared to the type 2 diabetes-normal cognitive function (T2D-NCF) group, the MCI subjects were olderand had higher TyG indexes, lower cognitive scores, and lower education levels (p < 0.01). After adjusting for the confounders, the TyG index was associated with MCI (OR = 7.37, 95% CI = 4.72-11.50, p < 0.01), and TyG-BMI was also associated with MCI (OR = 1.02, 95% CI = 1.01-1.02, p<0.01). The TyG index AUC was 0.79 (95% CI = 0.76-0.83). The consistency index of the nomogram was 0. 83[95% CI (0. 79, 0. 86)]. CONCLUSION Our results indicate that the TyG index and TyG-BMI are associated with MCI in T2D patients, and the TyG index is an excellent indicator of the risk of MCI in T2D patients. The nomogram incorporating the TyG index is useful to predict MCI risk in patients with T2D.
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Affiliation(s)
- Xue-Wei Tong
- First Affiliated Hospital of Harbin Medical University, Harbin, People’s Republic of China
| | - Yi-Tong Zhang
- First Affiliated Hospital of Harbin Medical University, Harbin, People’s Republic of China
| | - Zi-Wei Yu
- First Affiliated Hospital of Harbin Medical University, Harbin, People’s Republic of China
| | - Sheng-Dan Pu
- First Affiliated Hospital of Harbin Medical University, Harbin, People’s Republic of China
| | - Xin Li
- First Affiliated Hospital of Harbin Medical University, Harbin, People’s Republic of China
| | - Yu-Xin Xu
- First Affiliated Hospital of Harbin Medical University, Harbin, People’s Republic of China
| | - Yong-Yan Shan
- First Affiliated Hospital of Harbin Medical University, Harbin, People’s Republic of China
| | - Xin-Yuan Gao
- First Affiliated Hospital of Harbin Medical University, Harbin, People’s Republic of China
- Correspondence: Xin-Yuan Gao, Department of Endocrinology, The First Affiliated Hospital of Harbin Medical University, Harbin, 150001, Heilongjiang, People’s Republic of China, Tel +86-18846030512, Email
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Blázquez E, Hurtado-Carneiro V, LeBaut-Ayuso Y, Velázquez E, García-García L, Gómez-Oliver F, Ruiz-Albusac J, Ávila J, Pozo MÁ. Significance of Brain Glucose Hypometabolism, Altered Insulin Signal Transduction, and Insulin Resistance in Several Neurological Diseases. Front Endocrinol (Lausanne) 2022; 13:873301. [PMID: 35615716 PMCID: PMC9125423 DOI: 10.3389/fendo.2022.873301] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 03/23/2022] [Indexed: 12/14/2022] Open
Abstract
Several neurological diseases share pathological alterations, even though they differ in their etiology. Neuroinflammation, altered brain glucose metabolism, oxidative stress, mitochondrial dysfunction and amyloidosis are biological events found in those neurological disorders. Altered insulin-mediated signaling and brain glucose hypometabolism are characteristic signs observed in the brains of patients with certain neurological diseases, but also others such as type 2 diabetes mellitus and vascular diseases. Thus, significant reductions in insulin receptor autophosphorylation and Akt kinase activity, and increased GSK-3 activity and insulin resistance, have been reported in these neurological diseases as contributing to the decline in cognitive function. Supporting this relationship is the fact that nasal and hippocampal insulin administration has been found to improve cognitive function. Additionally, brain glucose hypometabolism precedes the unmistakable clinical manifestations of some of these diseases by years, which may become a useful early biomarker. Deficiencies in the major pathways of oxidative energy metabolism have been reported in patients with several of these neurological diseases, which supports the hypothesis of their metabolic background. This review remarks on the significance of insulin and brain glucose metabolism alterations as keystone common pathogenic substrates for certain neurological diseases, highlighting new potential targets.
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Affiliation(s)
- Enrique Blázquez
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, Complutense University, Madrid, Spain
- *Correspondence: Enrique Blázquez,
| | | | - Yannick LeBaut-Ayuso
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, Complutense University, Madrid, Spain
| | - Esther Velázquez
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, Complutense University, Madrid, Spain
| | - Luis García-García
- Pluridisciplinary Institute, Complutense University, IdISSC, Madrid, Spain
- Department of Pharmacology, Pharmacognosy and Botany, Faculty of Pharmacy, Complutense University, Madrid, Spain
| | - Francisca Gómez-Oliver
- Pluridisciplinary Institute, Complutense University, IdISSC, Madrid, Spain
- Department of Pharmacology, Pharmacognosy and Botany, Faculty of Pharmacy, Complutense University, Madrid, Spain
| | - Juan Miguel Ruiz-Albusac
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, Complutense University, Madrid, Spain
| | - Jesús Ávila
- Center of Molecular Biology “Severo Ochoa”, CSIC-UAM, Madrid, Spain
| | - Miguel Ángel Pozo
- Department of Physiology, Faculty of Medicine, Complutense University, Madrid, Spain
- Pluridisciplinary Institute, Complutense University, IdISSC, Madrid, Spain
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7
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Disentangling Mitochondria in Alzheimer's Disease. Int J Mol Sci 2021; 22:ijms222111520. [PMID: 34768950 PMCID: PMC8583788 DOI: 10.3390/ijms222111520] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 10/21/2021] [Accepted: 10/22/2021] [Indexed: 12/12/2022] Open
Abstract
Alzheimer's disease (AD) is a major cause of dementia in older adults and is fast becoming a major societal and economic burden due to an increase in life expectancy. Age seems to be the major factor driving AD, and currently, only symptomatic treatments are available. AD has a complex etiology, although mitochondrial dysfunction, oxidative stress, inflammation, and metabolic abnormalities have been widely and deeply investigated as plausible mechanisms for its neuropathology. Aβ plaques and hyperphosphorylated tau aggregates, along with cognitive deficits and behavioral problems, are the hallmarks of the disease. Restoration of mitochondrial bioenergetics, prevention of oxidative stress, and diet and exercise seem to be effective in reducing Aβ and in ameliorating learning and memory problems. Many mitochondria-targeted antioxidants have been tested in AD and are currently in development. However, larger streamlined clinical studies are needed to provide hard evidence of benefits in AD. This review discusses the causative factors, as well as potential therapeutics employed in the treatment of AD.
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8
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Wei Z, Koya J, Reznik SE. Insulin Resistance Exacerbates Alzheimer Disease via Multiple Mechanisms. Front Neurosci 2021; 15:687157. [PMID: 34349617 PMCID: PMC8326507 DOI: 10.3389/fnins.2021.687157] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Accepted: 06/23/2021] [Indexed: 12/12/2022] Open
Abstract
Alzheimer disease (AD) is a chronic neurodegenerative disease that accounts for 60–70% of dementia and is the sixth leading cause of death in the United States. The pathogenesis of this debilitating disorder is still not completely understood. New insights into the pathogenesis of AD are needed in order to develop novel pharmacologic approaches. In recent years, numerous studies have shown that insulin resistance plays a significant role in the development of AD. Over 80% of patients with AD have type II diabetes (T2DM) or abnormal serum glucose, suggesting that the pathogenic mechanisms of insulin resistance and AD likely overlap. Insulin resistance increases neuroinflammation, which promotes both amyloid β-protein deposition and aberrant tau phosphorylation. By increasing production of reactive oxygen species, insulin resistance triggers amyloid β-protein accumulation. Oxidative stress associated with insulin resistance also dysregulates glycogen synthase kinase 3-β (GSK-3β), which leads to increased tau phosphorylation. Both insulin and amyloid β-protein are metabolized by insulin degrading enzyme (IDE). Defects in this enzyme are the basis for a strong association between T2DM and AD. This review highlights multiple pathogenic mechanisms induced by insulin resistance that are implicated in AD. Several pharmacologic approaches to AD associated with insulin resistance are presented.
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Affiliation(s)
- Zenghui Wei
- Department of Pharmaceutical Sciences, St. John's University, New York, NY, United States
| | - Jagadish Koya
- Department of Pharmaceutical Sciences, St. John's University, New York, NY, United States
| | - Sandra E Reznik
- Department of Pharmaceutical Sciences, St. John's University, New York, NY, United States.,Department of Pathology, Albert Einstein College of Medicine, New York, NY, United States.,Department of Obstetrics and Gynecology and Women's Health, Albert Einstein College of Medicine, New York, NY, United States
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9
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Barber TM, Kyrou I, Randeva HS, Weickert MO. Mechanisms of Insulin Resistance at the Crossroad of Obesity with Associated Metabolic Abnormalities and Cognitive Dysfunction. Int J Mol Sci 2021; 22:ijms22020546. [PMID: 33430419 PMCID: PMC7827338 DOI: 10.3390/ijms22020546] [Citation(s) in RCA: 58] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 01/04/2021] [Accepted: 01/06/2021] [Indexed: 12/19/2022] Open
Abstract
Obesity mediates most of its direct medical sequelae through the development of insulin resistance (IR). The cellular effects of insulin occur through two main postreceptor pathways that are the phosphatidylinositol 3-kinase (PI3-K) and the mitogen-activated protein kinase (MAP-K) pathways. Obesity-related IR implicates the PI3-K pathway that confers the metabolic effects of insulin. Numerous and complex pathogenic pathways link obesity with the development of IR, including chronic inflammation, mitochondrial dysfunction (with the associated production of reactive oxygen species and endoplasmic reticulum stress), gut microbiota dysbiosis and adipose extracellular matrix remodelling. IR itself plays a key role in the development of metabolic dysfunction, including hypertension, dyslipidaemia and dysglycaemia. Furthermore, IR promotes weight gain related to secondary hyperinsulinaemia, with a resulting vicious cycle of worsening IR and its metabolic sequelae. Ultimately, IR underlies obesity-related conditions such as type 2 diabetes mellitus (T2D) and polycystic ovary syndrome (PCOS). IR also underlies many obesity-related malignancies, through the effects of compensatory hyperinsulinaemia on the relatively intact MAP-K insulin pathway, which controls cellular growth processes and mitoses. Furthermore, the emergent data over recent decades support an important role of obesity- and T2D-related central IR in the development of cognitive dysfunction, including effects on hippocampal synaptic plasticity. Importantly, IR is largely reversible through the optimisation of lifestyle factors that include regular engagement in physical activity with the avoidance of sedentariness, improved diet including increased fibre intake and sleep sufficiency. IR lies at the key crossroad between obesity and both metabolic and cognitive dysfunction. Given the importance of IR in the pathogenesis of many 21st century chronic diseases and its eminent reversibility, it is important that we all embrace and facilitate optimised lifestyles to improve the future health and wellbeing of the populace.
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Affiliation(s)
- Thomas M. Barber
- Warwickshire Institute for the Study of Diabetes, Endocrinology and Metabolism, University Hospitals Coventry and Warwickshire, Clifford Bridge Road, Coventry CV2 2DX, UK; (T.M.B.); (I.K.); (H.S.R.)
- Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry CV2 2DX, UK
| | - Ioannis Kyrou
- Warwickshire Institute for the Study of Diabetes, Endocrinology and Metabolism, University Hospitals Coventry and Warwickshire, Clifford Bridge Road, Coventry CV2 2DX, UK; (T.M.B.); (I.K.); (H.S.R.)
- Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry CV2 2DX, UK
- Aston Medical Research Institute, Aston Medical School, College of Health and Life Sciences, Aston University, Birmingham B4 7ET, UK
| | - Harpal S. Randeva
- Warwickshire Institute for the Study of Diabetes, Endocrinology and Metabolism, University Hospitals Coventry and Warwickshire, Clifford Bridge Road, Coventry CV2 2DX, UK; (T.M.B.); (I.K.); (H.S.R.)
- Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry CV2 2DX, UK
- Aston Medical Research Institute, Aston Medical School, College of Health and Life Sciences, Aston University, Birmingham B4 7ET, UK
| | - Martin O. Weickert
- Warwickshire Institute for the Study of Diabetes, Endocrinology and Metabolism, University Hospitals Coventry and Warwickshire, Clifford Bridge Road, Coventry CV2 2DX, UK; (T.M.B.); (I.K.); (H.S.R.)
- Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry CV2 2DX, UK
- Centre for Sport, Exercise and Life Sciences, Faculty of Health & Life Sciences, Coventry University, Coventry CV1 5FB, UK
- Correspondence:
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Brain expression of the vascular endothelial growth factor gene family in cognitive aging and alzheimer's disease. Mol Psychiatry 2021; 26:888-896. [PMID: 31332262 PMCID: PMC6980445 DOI: 10.1038/s41380-019-0458-5] [Citation(s) in RCA: 63] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 04/19/2019] [Accepted: 05/17/2019] [Indexed: 01/18/2023]
Abstract
Vascular endothelial growth factor (VEGF) is associated with the clinical manifestation of Alzheimer's disease (AD). However, the role of the VEGF gene family in neuroprotection is complex due to the number of biological pathways they regulate. This study explored associations between brain expression of VEGF genes with cognitive performance and AD pathology. Genetic, cognitive, and neuropathology data were acquired from the Religious Orders Study and Rush Memory and Aging Project. Expression of ten VEGF ligand and receptor genes was quantified using RNA sequencing of prefrontal cortex tissue. Global cognitive composite scores were calculated from 17 neuropsychological tests. β-amyloid and tau burden were measured at autopsy. Participants (n = 531) included individuals with normal cognition (n = 180), mild cognitive impairment (n = 148), or AD dementia (n = 203). Mean age at death was 89 years and 37% were male. Higher prefrontal cortex expression of VEGFB, FLT4, FLT1, and PGF was associated with worse cognitive trajectories (p ≤ 0.01). Increased expression of VEGFB and FLT4 was also associated with lower cognition scores at the last visit before death (p ≤ 0.01). VEGFB, FLT4, and FLT1 were upregulated among AD dementia compared with normal cognition participants (p ≤ 0.03). All four genes associated with cognition related to elevated β-amyloid (p ≤ 0.01) and/or tau burden (p ≤ 0.03). VEGF ligand and receptor genes, specifically genes relevant to FLT4 and FLT1 receptor signaling, are associated with cognition, longitudinal cognitive decline, and AD neuropathology. Future work should confirm these observations at the protein level to better understand how changes in VEGF transcription and translation relate to neurodegenerative disease.
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11
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Li QX, Gao H, Guo YX, Wang BY, Hua RX, Gao L, Shang HW, Lu X, Xu JD. GLP-1 and Underlying Beneficial Actions in Alzheimer's Disease, Hypertension, and NASH. Front Endocrinol (Lausanne) 2021; 12:721198. [PMID: 34552561 PMCID: PMC8450670 DOI: 10.3389/fendo.2021.721198] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2021] [Accepted: 08/23/2021] [Indexed: 12/24/2022] Open
Abstract
GLP-1 is derived from intestinal L cells, which takes effect through binding to GLP-1R and is inactivated by the enzyme dipeptidyl peptidase-4 (DPP-4). Since its discovery, GLP-1 has emerged as an incretin hormone for its facilitation in insulin release and reduction of insulin resistance (IR). However, GLP-1 possesses broader pharmacological effects including anti-inflammation, neuro-protection, regulating blood pressure (BP), and reducing lipotoxicity. These effects are interconnected to the physiological and pathological processes of Alzheimer's disease (AD), hypertension, and non-alcoholic steatohepatitis (NASH). Currently, the underlying mechanism of these effects is still not fully illustrated and a better understanding of them may help identify promising therapeutic targets of AD, hypertension, and NASH. Therefore, we focus on the biological characteristics of GLP-1, render an overview of the mechanism of GLP-1 effects in diseases, and investigate the potential of GLP-1 analogues for the treatment of related diseases in this review.
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Affiliation(s)
- Qiu-Xuan Li
- Clinical Medicine of “5+3” Program, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Han Gao
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
| | - Yue-Xin Guo
- Department of Oral Medicine, Basic Medical College, Capital Medical University, Beijing, China
| | - Bo-Ya Wang
- Eight Program of Clinical Medicine, Peking University Health Science Center, Beijing, China
| | - Rong-xuan Hua
- Clinical Medicine of “5+3” Program, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Lei Gao
- Department of Biomedical Informatics, School of Biomedical Engineering. Capital Medical University, Beijing, China
| | - Hong-Wei Shang
- Morphological Experiment Center, School of Basic Medical Sciences, Capital Medical University, Beijing, China
| | - Xin Lu
- Morphological Experiment Center, School of Basic Medical Sciences, Capital Medical University, Beijing, China
| | - Jing-Dong Xu
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
- *Correspondence: Jing-Dong Xu,
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Barthelson K, Newman M, Lardelli M. Sorting Out the Role of the Sortilin-Related Receptor 1 in Alzheimer's Disease. J Alzheimers Dis Rep 2020; 4:123-140. [PMID: 32587946 PMCID: PMC7306921 DOI: 10.3233/adr-200177] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/26/2020] [Indexed: 12/18/2022] Open
Abstract
Sortilin-related receptor 1 (SORL1) encodes a large, multi-domain containing, membrane-bound receptor involved in endosomal sorting of proteins between the trans-Golgi network, endosomes and the plasma membrane. It is genetically associated with Alzheimer's disease (AD), the most common form of dementia. SORL1 is a unique gene in AD, as it appears to show strong associations with the common, late-onset, sporadic form of AD and the rare, early-onset familial form of AD. Here, we review the genetics of SORL1 in AD and discuss potential roles it could play in AD pathogenesis.
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Affiliation(s)
- Karissa Barthelson
- School of Biological Sciences, University of Adelaide, Adelaide, SA, Australia
| | - Morgan Newman
- School of Biological Sciences, University of Adelaide, Adelaide, SA, Australia
| | - Michael Lardelli
- School of Biological Sciences, University of Adelaide, Adelaide, SA, Australia
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13
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Kubis-Kubiak A, Dyba A, Piwowar A. The Interplay between Diabetes and Alzheimer's Disease-In the Hunt for Biomarkers. Int J Mol Sci 2020; 21:ijms21082744. [PMID: 32326589 PMCID: PMC7215807 DOI: 10.3390/ijms21082744] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Revised: 04/09/2020] [Accepted: 04/12/2020] [Indexed: 02/07/2023] Open
Abstract
The brain is an organ in which energy metabolism occurs most intensively and glucose is an essential and dominant energy substrate. There have been many studies in recent years suggesting a close relationship between type 2 diabetes mellitus (T2DM) and Alzheimer’s disease (AD) as they have many pathophysiological features in common. The condition of hyperglycemia exposes brain cells to the detrimental effects of glucose, increasing protein glycation and is the cause of different non-psychiatric complications. Numerous observational studies show that not only hyperglycemia but also blood glucose levels near lower fasting limits (72 to 99 mg/dL) increase the incidence of AD, regardless of whether T2DM will develop in the future. As the comorbidity of these diseases and earlier development of AD in T2DM sufferers exist, new AD biomarkers are being sought for etiopathogenetic changes associated with early neurodegenerative processes as a result of carbohydrate disorders. The S100B protein seem to be interesting in this respect as it may be a potential candidate, especially important in early diagnostics of these diseases, given that it plays a role in both carbohydrate metabolism disorders and neurodegenerative processes. It is therefore necessary to clarify the relationship between the concentration of the S100B protein and glucose and insulin levels. This paper draws attention to a valuable research objective that may in the future contribute to a better diagnosis of early neurodegenerative changes, in particular in subjects with T2DM and may be a good basis for planning experiments related to this issue as well as a more detailed explanation of the relationship between the neuropathological disturbances and changes of glucose and insulin concentrations in the brain.
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Affiliation(s)
- Adriana Kubis-Kubiak
- Department of Toxicology, Faculty of Pharmacy, Wroclaw Medical University, 50367 Wroclaw, Poland;
- Correspondence:
| | - Aleksandra Dyba
- Students Science Club of the Department of Toxicology, Faculty of Pharmacy, Wroclaw Medical University, 50367 Wroclaw, Poland;
| | - Agnieszka Piwowar
- Department of Toxicology, Faculty of Pharmacy, Wroclaw Medical University, 50367 Wroclaw, Poland;
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Fonteh AN, Cipolla M, Chiang AJ, Edminster SP, Arakaki X, Harrington MG. Polyunsaturated Fatty Acid Composition of Cerebrospinal Fluid Fractions Shows Their Contribution to Cognitive Resilience of a Pre-symptomatic Alzheimer's Disease Cohort. Front Physiol 2020; 11:83. [PMID: 32116789 PMCID: PMC7034243 DOI: 10.3389/fphys.2020.00083] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Accepted: 01/27/2020] [Indexed: 12/12/2022] Open
Abstract
Alzheimer’s disease (AD) pathology is characterized by an early and prolonged decrease in the amyloid peptide (Aβ) levels concomitant with a later increase in phospho-tau concentrations in cerebrospinal fluid (CSF). We propose that changes in lipid metabolism can contribute to the abnormal processing of Aβ42 in AD. Our aim was to determine if polyunsaturated fatty acid (PUFA) metabolism can differentiate pre-symptomatic AD from normal aging and symptomatic AD. Using neuropsychology measures and Aβ42/T-tau in cerebrospinal fluid (CSF), we classify three groups of elderly study participants: cognitively healthy with normal Aβ42/T-tau (CH-NAT), cognitively healthy with pathological Aβ42/T-tau (CH-PAT), and AD individuals. We determined the size distribution and the concentration of CSF particles using light scattering and quantified PUFA composition in the nanoparticulate (NP) fraction, supernatant fluid (SF), and unesterified PUFA levels using gas chromatography combined with mass spectrometry. Four PUFAs (C20:2n-6, C20:3n-3, C22:4n-6, C22:5n-3) were enriched in NP of AD compared with CH-NAT. C20:3n-3 levels were higher in the NP fraction from AD compared with CH-PAT. When normalized to the number of NPs in CSF, PUFA levels were significantly higher in CH-NAT and CH-PAT compared with AD. In the SF fractions, only the levels of docosahexaenoic acid (DHA, C22:6n-3) differentiated all three clinical groups. Unesterified DHA was also higher in CH-NAT compared with the other clinical groups. Our studies also show that NP PUFAs in CH participants negatively correlate with CSF Aβ42 while C20:4n-6, DHA, and n-3 PUFAs in the SF fraction positively correlate with T-tau. The profile of PUFAs in different CSF fractions that correlate with Aβ42 or with T-tau are different for CH-NAT compared with CH-PAT. These studies show that PUFA metabolism is associated with amyloid and tau processing. Importantly, higher PUFA levels in the cognitively healthy study participants with abnormal Aβ42/T-tau suggest that PUFA enhances the cognitive resilience of the pre-symptomatic AD population. We propose that interventions that prevent PUFA depletion in the brain may prevent AD pathology by stabilizing Aβ42 and tau metabolism. Further studies to determine changes in PUFA composition during the progression from pre-symptomatic to AD should reveal novel biomarkers and potential preventive approaches.
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Affiliation(s)
- Alfred N Fonteh
- Neurosciences, Huntington Medical Research Institutes, Pasadena, CA, United States
| | - Matthew Cipolla
- Neurosciences, Huntington Medical Research Institutes, Pasadena, CA, United States
| | - Abby J Chiang
- Neurosciences, Huntington Medical Research Institutes, Pasadena, CA, United States
| | - Sarah P Edminster
- Neurosciences, Huntington Medical Research Institutes, Pasadena, CA, United States
| | - Xianghong Arakaki
- Neurosciences, Huntington Medical Research Institutes, Pasadena, CA, United States
| | - Michael G Harrington
- Neurosciences, Huntington Medical Research Institutes, Pasadena, CA, United States
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Rorbach-Dolata A, Piwowar A. Neurometabolic Evidence Supporting the Hypothesis of Increased Incidence of Type 3 Diabetes Mellitus in the 21st Century. BIOMED RESEARCH INTERNATIONAL 2019; 2019:1435276. [PMID: 31428627 PMCID: PMC6679855 DOI: 10.1155/2019/1435276] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Accepted: 07/03/2019] [Indexed: 12/11/2022]
Abstract
The most recent evidence supports the existence of a link between type 2 diabetes (T2DM) and Alzheimer's Disease (AD), described by the new term: type 3 diabetes (T3D). The increasing incidence of T2DM in the 21st century and accompanying reports on the higher risk of AD in diabetic patients prompts the search for pathways linking glycemia disturbances and neurodegeneration. It is suggested that hyperglycemia may lead to glutamate-induced excitotoxicity, a pathological process resulting from excessive depolarization of membrane and uncontrolled calcium ion influx into neuronal cells. On the other hand, it has been confirmed that peripheral insulin resistance triggers insulin resistance in the brain, which may consequently contribute to AD by amyloid beta accumulation, tau phosphorylation, oxidative stress, advanced glycation end products, and apoptosis. Some literature sources suggest significant amylin involvement in additional amyloid formation in the central nervous system, especially under hyperamylinemic conditions. It is particularly important to provide early diagnostics in people with metabolic disturbances, especially including fasting insulin and HOMA-IR, which are necessary to reveal insulin resistance. The present review reveals the most recent and important evidence associated with the phenomenon of T3D and discusses the potential lacks of prevention and diagnostics for diabetes which might result in neurometabolic disorders, from a pharmacotherapy perspective.
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Affiliation(s)
- Anna Rorbach-Dolata
- Department of Toxicology, Faculty of Pharmacy with the Division of Laboratory Diagnostics, Wroclaw Medical University, Borowska 211, 50-552 Wroclaw, Poland
| | - Agnieszka Piwowar
- Department of Toxicology, Faculty of Pharmacy with the Division of Laboratory Diagnostics, Wroclaw Medical University, Borowska 211, 50-552 Wroclaw, Poland
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16
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Delikkaya B, Moriel N, Tong M, Gallucci G, de la Monte SM. Altered expression of insulin-degrading enzyme and regulator of calcineurin in the rat intracerebral streptozotocin model and human apolipoprotein E-ε4-associated Alzheimer's disease. ALZHEIMER'S & DEMENTIA (AMSTERDAM, NETHERLANDS) 2019; 11:392-404. [PMID: 31193223 PMCID: PMC6522644 DOI: 10.1016/j.dadm.2019.03.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
INTRODUCTION This study assesses insulin-degrading enzyme (IDE) and regulator of calcineurin 1 (RCAN1) as potential mediators of brain insulin deficiency and neurodegeneration in experimental and human Alzheimer's disease (AD). METHODS Temporal lobes from Long Evans rats treated with intracerebral streptozotocin or vehicle and postmortem frontal lobes from humans with normal aging AD (Braak 0-2), moderate (Braak 3-4) AD, or advanced (Braak 5-6) AD were used to measure IDE and RCAN mRNA and protein. RESULTS Intracerebral streptozotocin significantly increased IDE and RCAN mRNA and protein. In humans with apolipoprotein E (ApoE) ε3/ε4 or ε4/ε4 and AD, IDE was elevated at Braak 3-4, but at Braak 5-6, IDE expression was significantly reduced. RCAN1 mRNA was similarly reduced in ApoE ε4+ patients with moderate or severe AD, whereas RCAN1 protein declined with the severity of AD and ApoE ε4 dose. DISCUSSION The findings suggest that IDE and RCAN1 differentially modulate brain insulin signaling in relation to AD severity and ApoE genotype.
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Affiliation(s)
- Büşra Delikkaya
- Istanbul University-Cerrahpasa Cerrahpasa Medical Faculty, Istanbul, Turkey
| | - Natalia Moriel
- Department of Medicine, Rhode Island Hospital, Providence, RI, USA
| | - Ming Tong
- Department of Medicine, Rhode Island Hospital, Providence, RI, USA,Alpert Medical School of Brown University, Providence, RI, USA
| | - Gina Gallucci
- Department of Medicine, Rhode Island Hospital, Providence, RI, USA
| | - Suzanne M. de la Monte
- Department of Medicine, Rhode Island Hospital, Providence, RI, USA,Alpert Medical School of Brown University, Providence, RI, USA,Departments of Neurology and Neurosurgery, Rhode Island Hospital, Providence, RI, USA,Department of Pathology and Laboratory Medicine, Providence VA Medical Center, Providence, RI, USA,Corresponding author. Tel.: +401-444-7364; Fax: +401-444-2939.
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17
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Neuroprotective Actions of Glucagon-Like Peptide-1 (GLP-1) Analogues in Alzheimer's and Parkinson's Diseases. CNS Drugs 2019; 33:209-223. [PMID: 30511349 DOI: 10.1007/s40263-018-0593-6] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The current absence of effective treatments for Alzheimer's disease (AD) and Parkinson's disease (PD) reflects an incomplete knowledge of the underlying disease processes. Considerable efforts have been made to investigate the central pathological features of these diseases, giving rise to numerous attempts to develop compounds that interfere with such features. However, further characterization of the molecular targets within the interconnected AD and PD pathways is still required. Impaired brain insulin signaling has emerged as a feature that contributes to neuronal dysfunction in both AD and PD, leading to strategies aiming at restoring this pathway in the brain. Long-acting glucagon-like peptide-1 (GLP-1) analogues marketed for treatment of type 2 diabetes mellitus have been tested and have shown encouraging protective actions in experimental models of AD and PD as well as in initial clinical trials. We review studies revealing the neuroprotective actions of GLP-1 analogues in pre-clinical models of AD and PD and promising results from recent clinical trials.
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18
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Hussain R, Zubair H, Pursell S, Shahab M. Neurodegenerative Diseases: Regenerative Mechanisms and Novel Therapeutic Approaches. Brain Sci 2018; 8:E177. [PMID: 30223579 PMCID: PMC6162719 DOI: 10.3390/brainsci8090177] [Citation(s) in RCA: 104] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Revised: 09/03/2018] [Accepted: 09/12/2018] [Indexed: 12/12/2022] Open
Abstract
Regeneration refers to regrowth of tissue in the central nervous system. It includes generation of new neurons, glia, myelin, and synapses, as well as the regaining of essential functions: sensory, motor, emotional and cognitive abilities. Unfortunately, regeneration within the nervous system is very slow compared to other body systems. This relative slowness is attributed to increased vulnerability to irreversible cellular insults and the loss of function due to the very long lifespan of neurons, the stretch of cells and cytoplasm over several dozens of inches throughout the body, insufficiency of the tissue-level waste removal system, and minimal neural cell proliferation/self-renewal capacity. In this context, the current review summarized the most common features of major neurodegenerative disorders; their causes and consequences and proposed novel therapeutic approaches.
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Affiliation(s)
- Rashad Hussain
- Center for Translational Neuromedicine, University of Rochester, NY 14642, USA.
| | - Hira Zubair
- Department of Animal Sciences, Quaid-i-Azam University, Islamabad 45320, Pakistan.
| | - Sarah Pursell
- Center for Translational Neuromedicine, University of Rochester, NY 14642, USA.
| | - Muhammad Shahab
- Department of Animal Sciences, Quaid-i-Azam University, Islamabad 45320, Pakistan.
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Postmortem Brain, Cerebrospinal Fluid, and Blood Neurotrophic Factor Levels in Alzheimer's Disease: A Systematic Review and Meta-Analysis. J Mol Neurosci 2018; 65:289-300. [PMID: 29956088 DOI: 10.1007/s12031-018-1100-8] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Accepted: 06/12/2018] [Indexed: 01/02/2023]
Abstract
Accumulating evidence suggest that aberrations of neurotrophic factors are involved in the etiology and pathogenesis of Alzheimer's disease (AD), but clinical data were inconsistent. Therefore, a meta-analysis on neurotrophic factor levels in AD is necessary. We performed a systematic review of blood, CSF, and post-mortem brain neurotrophic factor levels in patients with AD compared with controls and quantitatively summarized the clinical data in blood and CSF with a meta-analytical technique. A systematic search of PubMed and Web of Science identified 98 articles in this study (with samples more than 9000). Random effects meta-analysis demonstrated that peripheral blood BDNF levels were significantly decreased in AD patients compared with controls. However, blood NGF, IGF, and VEGF did not show significant differences between cases and controls. In CSF, random effects meta-analysis showed significantly deceased BDNF and increased NGF levels in patients with AD, whereas IGF and VEGF did not show significant differences between the AD group and control group. In addition, 23 post-mortem studies were included in the systematic review. Although data from post-mortem brains were not always consistent across studies, most studies suggested decreased BDNF and increased (pro)NGF levels in hippocampus and neocortex of patients with AD. These results provide strong clinical evidence that AD is accompanied by an aberrant neurotrophin profile, and future investigations into neurotrophins as biomarkers (especially CSF BDNF and NGF) and therapeutic targets for AD may be warranted.
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20
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Batista AF, Forny-Germano L, Clarke JR, Lyra E Silva NM, Brito-Moreira J, Boehnke SE, Winterborn A, Coe BC, Lablans A, Vital JF, Marques SA, Martinez AM, Gralle M, Holscher C, Klein WL, Houzel JC, Ferreira ST, Munoz DP, De Felice FG. The diabetes drug liraglutide reverses cognitive impairment in mice and attenuates insulin receptor and synaptic pathology in a non-human primate model of Alzheimer's disease. J Pathol 2018; 245:85-100. [PMID: 29435980 PMCID: PMC5947670 DOI: 10.1002/path.5056] [Citation(s) in RCA: 160] [Impact Index Per Article: 26.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Revised: 01/13/2018] [Accepted: 02/05/2018] [Indexed: 12/21/2022]
Abstract
Alzheimer's disease (AD) is a devastating neurological disorder that still lacks an effective treatment, and this has stimulated an intense pursuit of disease-modifying therapeutics. Given the increasingly recognized link between AD and defective brain insulin signaling, we investigated the actions of liraglutide, a glucagon-like peptide-1 (GLP-1) analog marketed for treatment of type 2 diabetes, in experimental models of AD. Insulin receptor pathology is an important feature of AD brains that impairs the neuroprotective actions of central insulin signaling. Here, we show that liraglutide prevented the loss of brain insulin receptors and synapses, and reversed memory impairment induced by AD-linked amyloid-β oligomers (AβOs) in mice. Using hippocampal neuronal cultures, we determined that the mechanism of neuroprotection by liraglutide involves activation of the PKA signaling pathway. Infusion of AβOs into the lateral cerebral ventricle of non-human primates (NHPs) led to marked loss of insulin receptors and synapses in brain regions related to memory. Systemic treatment of NHPs with liraglutide provided partial protection, decreasing AD-related insulin receptor, synaptic, and tau pathology in specific brain regions. Synapse damage and elimination are amongst the earliest known pathological changes and the best correlates of memory impairment in AD. The results illuminate mechanisms of neuroprotection by liraglutide, and indicate that GLP-1 receptor activation may be harnessed to protect brain insulin receptors and synapses in AD. © 2018 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.
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Affiliation(s)
- Andre F Batista
- Institute of Medical Biochemistry Leopoldo de Meis, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Leticia Forny-Germano
- Institute of Medical Biochemistry Leopoldo de Meis, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Julia R Clarke
- School of Pharmacy, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Natalia M Lyra E Silva
- Institute of Medical Biochemistry Leopoldo de Meis, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Jordano Brito-Moreira
- Institute of Medical Biochemistry Leopoldo de Meis, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Susan E Boehnke
- Centre for Neuroscience Studies, Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada
| | | | - Brian C Coe
- Centre for Neuroscience Studies, Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada
| | - Ann Lablans
- Centre for Neuroscience Studies, Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada
| | - Juliana F Vital
- Institute of Medical Biochemistry Leopoldo de Meis, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Suelen A Marques
- Departament of Neurobiology, Fluminense Federal University, Niteroi, Brazil
| | - Ana Mb Martinez
- Department of Pathology, Faculty of Medicine, Hospital Universitário Clementino Fraga Filho, UFRJ, Rio de Janeiro, Brazil
| | - Matthias Gralle
- Institute of Medical Biochemistry Leopoldo de Meis, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Christian Holscher
- Division of Biomed and Life Sciences, Faculty of Health and Medicine Lancaster University, Lancaster, UK
| | - William L Klein
- Department of Neurobiology, Northwestern University, Evanston, Illinois, USA
| | - Jean-Christophe Houzel
- Institute of Biomedical Sciences, 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.,Institute of Biophysics Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Douglas P Munoz
- Centre for Neuroscience Studies, Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada
| | - Fernanda G De Felice
- Institute of Medical Biochemistry Leopoldo de Meis, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.,Centre for Neuroscience Studies, Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada
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21
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Ribarič S. Peptides as Potential Therapeutics for Alzheimer's Disease. Molecules 2018; 23:E283. [PMID: 29385735 PMCID: PMC6017258 DOI: 10.3390/molecules23020283] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 01/26/2018] [Accepted: 01/28/2018] [Indexed: 12/22/2022] Open
Abstract
Intracellular synthesis, folding, trafficking and degradation of proteins are controlled and integrated by proteostasis. The frequency of protein misfolding disorders in the human population, e.g., in Alzheimer's disease (AD), is increasing due to the aging population. AD treatment options are limited to symptomatic interventions that at best slow-down disease progression. The key biochemical change in AD is the excessive accumulation of per-se non-toxic and soluble amyloid peptides (Aβ(1-37/44), in the intracellular and extracellular space, that alters proteostasis and triggers Aβ modification (e.g., by reactive oxygen species (ROS)) into toxic intermediate, misfolded soluble Aβ peptides, Aβ dimers and Aβ oligomers. The toxic intermediate Aβ products aggregate into progressively less toxic and less soluble protofibrils, fibrils and senile plaques. This review focuses on peptides that inhibit toxic Aβ oligomerization, Aβ aggregation into fibrils, or stabilize Aβ peptides in non-toxic oligomers, and discusses their potential for AD treatment.
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Affiliation(s)
- Samo Ribarič
- Institute of Pathophysiology, Faculty of Medicine, Zaloška 4, SI-1000 Ljubljana, Slovenia.
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22
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The diabetic brain and cognition. J Neural Transm (Vienna) 2017; 124:1431-1454. [PMID: 28766040 DOI: 10.1007/s00702-017-1763-2] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Accepted: 07/13/2017] [Indexed: 12/20/2022]
Abstract
The prevalence of both Alzheimer's disease (AD) and vascular dementia (VaD) is increasing with the aging of the population. Studies from the last several years have shown that people with diabetes have an increased risk for dementia and cognitive impairment. Therefore, the authors of this consensus review tried to elaborate on the role of diabetes, especially diabetes type 2 (T2DM) in both AD and VaD. Based on the clinical and experimental work of scientists from 18 countries participating in the International Congress on Vascular Disorders and on literature search using PUBMED, it can be concluded that T2DM is a risk factor for both, AD and VaD, based on a pathology of glucose utilization. This pathology is the consequence of a disturbance of insulin-related mechanisms leading to brain insulin resistance. Although the underlying pathological mechanisms for AD and VaD are different in many aspects, the contribution of T2DM and insulin resistant brain state (IRBS) to cerebrovascular disturbances in both disorders cannot be neglected. Therefore, early diagnosis of metabolic parameters including those relevant for T2DM is required. Moreover, it is possible that therapeutic options utilized today for diabetes treatment may also have an effect on the risk for dementia. T2DM/IRBS contribute to pathological processes in AD and VaD.
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23
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Martin B, Wang R, Cong WN, Daimon CM, Wu WW, Ni B, Becker KG, Lehrmann E, Wood WH, Zhang Y, Etienne H, van Gastel J, Azmi A, Janssens J, Maudsley S. Altered learning, memory, and social behavior in type 1 taste receptor subunit 3 knock-out mice are associated with neuronal dysfunction. J Biol Chem 2017; 292:11508-11530. [PMID: 28522608 DOI: 10.1074/jbc.m116.773820] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Revised: 05/03/2017] [Indexed: 12/19/2022] Open
Abstract
The type 1 taste receptor member 3 (T1R3) is a G protein-coupled receptor involved in sweet-taste perception. Besides the tongue, the T1R3 receptor is highly expressed in brain areas implicated in cognition, including the hippocampus and cortex. As cognitive decline is often preceded by significant metabolic or endocrinological dysfunctions regulated by the sweet-taste perception system, we hypothesized that a disruption of the sweet-taste perception in the brain could have a key role in the development of cognitive dysfunction. To assess the importance of the sweet-taste receptors in the brain, we conducted transcriptomic and proteomic analyses of cortical and hippocampal tissues isolated from T1R3 knock-out (T1R3KO) mice. The effect of an impaired sweet-taste perception system on cognition functions were examined by analyzing synaptic integrity and performing animal behavior on T1R3KO mice. Although T1R3KO mice did not present a metabolically disrupted phenotype, bioinformatic interpretation of the high-dimensionality data indicated a strong neurodegenerative signature associated with significant alterations in pathways involved in neuritogenesis, dendritic growth, and synaptogenesis. Furthermore, a significantly reduced dendritic spine density was observed in T1R3KO mice together with alterations in learning and memory functions as well as sociability deficits. Taken together our data suggest that the sweet-taste receptor system plays an important neurotrophic role in the extralingual central nervous tissue that underpins synaptic function, memory acquisition, and social behavior.
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Affiliation(s)
- Bronwen Martin
- From the Metabolism Unit, NIA, National Institutes of Health, Baltimore, Maryland 21224
| | - Rui Wang
- From the Metabolism Unit, NIA, National Institutes of Health, Baltimore, Maryland 21224
| | - Wei-Na Cong
- From the Metabolism Unit, NIA, National Institutes of Health, Baltimore, Maryland 21224
| | - Caitlin M Daimon
- From the Metabolism Unit, NIA, National Institutes of Health, Baltimore, Maryland 21224
| | - Wells W Wu
- From the Metabolism Unit, NIA, National Institutes of Health, Baltimore, Maryland 21224
| | - Bin Ni
- the Receptor Pharmacology Unit, NIA, National Institutes of Health, Baltimore, Maryland 21224
| | - Kevin G Becker
- the Gene Expression and Genomics Unit, NIA, National Institutes of Health, Baltimore, Maryland 21224
| | - Elin Lehrmann
- the Gene Expression and Genomics Unit, NIA, National Institutes of Health, Baltimore, Maryland 21224
| | - William H Wood
- the Gene Expression and Genomics Unit, NIA, National Institutes of Health, Baltimore, Maryland 21224
| | - Yongqing Zhang
- the Gene Expression and Genomics Unit, NIA, National Institutes of Health, Baltimore, Maryland 21224
| | - Harmonie Etienne
- the Translational Neurobiology Group, VIB Department of Molecular Genetics, University of Antwerp, AN-2610 Antwerp, Belgium, and.,the Department of Biomedical Sciences, University of Antwerp, AN-2610 Antwerp, Belgium
| | - Jaana van Gastel
- the Translational Neurobiology Group, VIB Department of Molecular Genetics, University of Antwerp, AN-2610 Antwerp, Belgium, and.,the Department of Biomedical Sciences, University of Antwerp, AN-2610 Antwerp, Belgium
| | - Abdelkrim Azmi
- the Translational Neurobiology Group, VIB Department of Molecular Genetics, University of Antwerp, AN-2610 Antwerp, Belgium, and.,the Department of Biomedical Sciences, University of Antwerp, AN-2610 Antwerp, Belgium
| | - Jonathan Janssens
- the Translational Neurobiology Group, VIB Department of Molecular Genetics, University of Antwerp, AN-2610 Antwerp, Belgium, and.,the Department of Biomedical Sciences, University of Antwerp, AN-2610 Antwerp, Belgium
| | - Stuart Maudsley
- the Receptor Pharmacology Unit, NIA, National Institutes of Health, Baltimore, Maryland 21224, .,the Translational Neurobiology Group, VIB Department of Molecular Genetics, University of Antwerp, AN-2610 Antwerp, Belgium, and.,the Department of Biomedical Sciences, University of Antwerp, AN-2610 Antwerp, Belgium
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Diehl T, Mullins R, Kapogiannis D. Insulin resistance in Alzheimer's disease. Transl Res 2017; 183:26-40. [PMID: 28034760 PMCID: PMC5393926 DOI: 10.1016/j.trsl.2016.12.005] [Citation(s) in RCA: 85] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Revised: 12/05/2016] [Accepted: 12/06/2016] [Indexed: 12/14/2022]
Abstract
The links between systemic insulin resistance (IR), brain-specific IR, and Alzheimer's disease (AD) have been an extremely productive area of current research. This review will cover the fundamentals and pathways leading to IR, its connection to AD via cellular mechanisms, the most prominent methods and models used to examine it, an introduction to the role of extracellular vesicles (EVs) as a source of biomarkers for IR and AD, and an overview of modern clinical studies on the subject. To provide additional context, we also present a novel analysis of the spatial correlation of gene expression in the brain with the aid of Allen Human Brain Atlas data. Ultimately, examining the relation between IR and AD can be seen as a means of advancing the understanding of both disease states, with IR being a promising target for therapeutic strategies in AD treatment. In conclusion, we highlight the therapeutic potential of targeting brain IR in AD and the main strategies to pursue this goal.
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Affiliation(s)
- Thomas Diehl
- Laboratory of Neurosciences, Intramural Research Program, National Institute on Aging/National Institutes of Health (NIA/NIH), Baltimore, MD
| | - Roger Mullins
- Laboratory of Neurosciences, Intramural Research Program, National Institute on Aging/National Institutes of Health (NIA/NIH), Baltimore, MD
| | - Dimitrios Kapogiannis
- Laboratory of Neurosciences, Intramural Research Program, National Institute on Aging/National Institutes of Health (NIA/NIH), Baltimore, MD.
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de la Monte SM. Insulin Resistance and Neurodegeneration: Progress Towards the Development of New Therapeutics for Alzheimer's Disease. Drugs 2017; 77:47-65. [PMID: 27988872 PMCID: PMC5575843 DOI: 10.1007/s40265-016-0674-0] [Citation(s) in RCA: 194] [Impact Index Per Article: 27.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Alzheimer's disease (AD) should be regarded as a degenerative metabolic disease caused by brain insulin resistance and deficiency, and overlapping with the molecular, biochemical, pathophysiological, and metabolic dysfunctions in diabetes mellitus, non-alcoholic fatty liver disease, and metabolic syndrome. Although most of the diagnostic and therapeutic approaches over the past several decades have focused on amyloid-beta (Aβ42) and aberrantly phosphorylated tau, which could be caused by consequences of brain insulin resistance, the broader array of pathologies including white matter atrophy with loss of myelinated fibrils and leukoaraiosis, non-Aβ42 microvascular disease, dysregulated lipid metabolism, mitochondrial dysfunction, astrocytic gliosis, neuro-inflammation, and loss of synapses vis-à-vis growth of dystrophic neurites, is not readily accounted for by Aβ42 accumulations, but could be explained by dysregulated insulin/IGF-1 signaling with attendant impairments in signal transduction and gene expression. This review covers the diverse range of brain abnormalities in AD and discusses how insulins, incretins, and insulin sensitizers could be utilized to treat at different stages of neurodegeneration.
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Affiliation(s)
- Suzanne M de la Monte
- Department of Neurology, Rhode Island Hospital, and the Alpert Medical School of Brown University, Pierre Galletti Research Building, 55 Claverick Street, Room 419, Providence, RI, 02903, USA.
- Department of Neurosurgery, Rhode Island Hospital, and the Alpert Medical School of Brown University, Providence, RI, USA.
- Department of Neuropathology, Rhode Island Hospital, and the Alpert Medical School of Brown University, Providence, RI, USA.
- Department of Pathology, Rhode Island Hospital, and the Alpert Medical School of Brown University, Providence, RI, USA.
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Ribarič S. The Rationale for Insulin Therapy in Alzheimer's Disease. Molecules 2016; 21:molecules21060689. [PMID: 27240327 PMCID: PMC6273626 DOI: 10.3390/molecules21060689] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Revised: 05/14/2016] [Accepted: 05/19/2016] [Indexed: 12/30/2022] Open
Abstract
Alzheimer's disease (AD) is the most common form of dementia, with a prevalence that increases with age. By 2050, the worldwide number of patients with AD is projected to reach more than 140 million. The prominent signs of AD are progressive memory loss, accompanied by a gradual decline in cognitive function and premature death. AD is the clinical manifestation of altered proteostasis. The initiating step of altered proteostasis in most AD patients is not known. The progression of AD is accelerated by several chronic disorders, among which the contribution of diabetes to AD is well understood at the cell biology level. The pathological mechanisms of AD and diabetes interact and tend to reinforce each other, thus accelerating cognitive impairment. At present, only symptomatic interventions are available for treating AD. To optimise symptomatic treatment, a personalised therapy approach has been suggested. Intranasal insulin administration seems to open the possibility for a safe, and at least in the short term, effective symptomatic intervention that delays loss of cognition in AD patients. This review summarizes the interactions of AD and diabetes from the cell biology to the patient level and the clinical results of intranasal insulin treatment of cognitive decline in AD.
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Affiliation(s)
- Samo Ribarič
- Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Zaloška 4, SI-1000 Ljubljana, Slovenia.
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Lu H, Zhu XC, Jiang T, Yu JT, Tan L. Body fluid biomarkers in Alzheimer's disease. ANNALS OF TRANSLATIONAL MEDICINE 2015; 3:70. [PMID: 25992369 DOI: 10.3978/j.issn.2305-5839.2015.02.13] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Accepted: 02/03/2015] [Indexed: 01/09/2023]
Abstract
A heterogeneous and slowly progressive disease with extracellular amyloid-β (Aβ) deposits and intracellular hyperphosphorylated tau protein aggregates, Alzheimer's disease (AD) is already a hard nut to crack, featured with cognitive decline and memory lapse. Body fluid biomarkers are proved to be useful in exploring further study of AD, might benefit for a full comprehension of the etiopathogenesis, an improved precision of the prognosis and diagnosis, and a positive response of treatments. The cerebrospinal fluid biomarkers Aβ, total tau, and hyperphosphorylated tau reflect the main pathologic changes of AD. We also review data from several novel biomarkers, such as, β-site APP cleaving enzyme 1, soluble amyloid precursor proteins α and β, soluble Aβ oligomers and so on, which are associated with the occurrence and deterioration of this disease and couldn't be ignored. The rationale for the clinical use of those biomarkers, the challenges faced with and the properties of the most appropriate biomarkers are also summarized in the paper. We aim to find several ideal biomarkers to improve the diagnosis and optimize the treatment respectively.
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Affiliation(s)
- Huan Lu
- 1 Department of Neurology, Qingdao Municipal Hospital, Nanjing Medical University, Nanjing 210029, China ; 2 Department of Neurology, Nanjing First Hospital, Nanjing Medical University, Nanjing 210029, China ; 3 Department of Neurology, Qingdao Municipal Hospital, School of Medicine, Qingdao University, Qingdao 266001, China ; 4 Memory and Aging Center, Department of Neurology, University of California, San Francisco, CA 94158, USA
| | - Xi-Chen Zhu
- 1 Department of Neurology, Qingdao Municipal Hospital, Nanjing Medical University, Nanjing 210029, China ; 2 Department of Neurology, Nanjing First Hospital, Nanjing Medical University, Nanjing 210029, China ; 3 Department of Neurology, Qingdao Municipal Hospital, School of Medicine, Qingdao University, Qingdao 266001, China ; 4 Memory and Aging Center, Department of Neurology, University of California, San Francisco, CA 94158, USA
| | - Teng Jiang
- 1 Department of Neurology, Qingdao Municipal Hospital, Nanjing Medical University, Nanjing 210029, China ; 2 Department of Neurology, Nanjing First Hospital, Nanjing Medical University, Nanjing 210029, China ; 3 Department of Neurology, Qingdao Municipal Hospital, School of Medicine, Qingdao University, Qingdao 266001, China ; 4 Memory and Aging Center, Department of Neurology, University of California, San Francisco, CA 94158, USA
| | - Jin-Tai Yu
- 1 Department of Neurology, Qingdao Municipal Hospital, Nanjing Medical University, Nanjing 210029, China ; 2 Department of Neurology, Nanjing First Hospital, Nanjing Medical University, Nanjing 210029, China ; 3 Department of Neurology, Qingdao Municipal Hospital, School of Medicine, Qingdao University, Qingdao 266001, China ; 4 Memory and Aging Center, Department of Neurology, University of California, San Francisco, CA 94158, USA
| | - Lan Tan
- 1 Department of Neurology, Qingdao Municipal Hospital, Nanjing Medical University, Nanjing 210029, China ; 2 Department of Neurology, Nanjing First Hospital, Nanjing Medical University, Nanjing 210029, China ; 3 Department of Neurology, Qingdao Municipal Hospital, School of Medicine, Qingdao University, Qingdao 266001, China ; 4 Memory and Aging Center, Department of Neurology, University of California, San Francisco, CA 94158, USA
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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: 311] [Impact Index Per Article: 28.3] [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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