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Tang AS, Oskotsky T, Havaldar S, Mantyh WG, Bicak M, Solsberg CW, Woldemariam S, Zeng B, Hu Z, Oskotsky B, Dubal D, Allen IE, Glicksberg BS, Sirota M. Deep phenotyping of Alzheimer's disease leveraging electronic medical records identifies sex-specific clinical associations. Nat Commun 2022; 13:675. [PMID: 35115528 PMCID: PMC8814236 DOI: 10.1038/s41467-022-28273-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Accepted: 01/18/2022] [Indexed: 12/14/2022] Open
Abstract
Alzheimer's Disease (AD) is a neurodegenerative disorder that is still not fully understood. Sex modifies AD vulnerability, but the reasons for this are largely unknown. We utilize two independent electronic medical record (EMR) systems across 44,288 patients to perform deep clinical phenotyping and network analysis to gain insight into clinical characteristics and sex-specific clinical associations in AD. Embeddings and network representation of patient diagnoses demonstrate greater comorbidity interactions in AD in comparison to matched controls. Enrichment analysis identifies multiple known and new diagnostic, medication, and lab result associations across the whole cohort and in a sex-stratified analysis. With this data-driven method of phenotyping, we can represent AD complexity and generate hypotheses of clinical factors that can be followed-up for further diagnostic and predictive analyses, mechanistic understanding, or drug repurposing and therapeutic approaches.
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Affiliation(s)
- Alice S Tang
- Bakar Computational Health Sciences Institute, UCSF, San Francisco, CA, USA.
- Graduate Program in Bioengineering, UCSF, San Francisco, CA, USA.
- School of Medicine, UCSF, San Francisco, CA, USA.
| | - Tomiko Oskotsky
- Bakar Computational Health Sciences Institute, UCSF, San Francisco, CA, USA
- Department of Pediatrics, UCSF, San Francisco, CA, USA
| | - Shreyas Havaldar
- Hasso Plattner Institute for Digital Health at Mount Sinai, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - William G Mantyh
- Department of Neurology, University of Minnesota School of Medicine, Minneapolis, MN, USA
| | - Mesude Bicak
- Hasso Plattner Institute for Digital Health at Mount Sinai, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Caroline Warly Solsberg
- Pharmaceutical Sciences and Pharmacogenomics, UCSF, San Francisco, CA, USA
- Department of Neurology and Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, 94158, USA
- Memory and Aging Center, UCSF, San Francisco, CA, USA
| | - Sarah Woldemariam
- Bakar Computational Health Sciences Institute, UCSF, San Francisco, CA, USA
| | - Billy Zeng
- School of Medicine, UCSF, San Francisco, CA, USA
| | - Zicheng Hu
- Bakar Computational Health Sciences Institute, UCSF, San Francisco, CA, USA
| | - Boris Oskotsky
- Bakar Computational Health Sciences Institute, UCSF, San Francisco, CA, USA
| | - Dena Dubal
- Department of Neurology and Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, 94158, USA
| | - Isabel E Allen
- Department of Epidemiology and Biostatistics, UCSF, San Francisco, CA, USA
| | - Benjamin S Glicksberg
- Hasso Plattner Institute for Digital Health at Mount Sinai, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Marina Sirota
- Bakar Computational Health Sciences Institute, UCSF, San Francisco, CA, USA.
- Department of Pediatrics, UCSF, San Francisco, CA, USA.
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Chakraborty A, Sami SA, Marma KKS. A comprehensive review on RAGE-facilitated pathological pathways connecting Alzheimer’s disease, diabetes mellitus, and cardiovascular diseases. THE EGYPTIAN JOURNAL OF INTERNAL MEDICINE 2021. [DOI: 10.1186/s43162-021-00081-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
Alzheimer’s disease (AD), cardiovascular disease (CVD), and diabetes are some of the most common causes of morbidity and mortality among the aging populations and cause a heavy burden on the worldwide healthcare system. In this review, we briefly highlighted cellular inflammation-based pathways of diabetes mellitus and CVD through receptor for advanced glycation end products AGEs or RAGE leading to Alzheimer’s disease and interrelation between these vascular and metabolic disorders. The articles were retrieved from Google Scholar, Science Direct, and PubMed databases using the following terms: Alzheimer’s; AGEs; RAGE; RAGE in Alzheimer’s; AGEs in Alzheimer’s; RAGE in diabetes; RAGE related pathways of CVD; RAGE in hypertension; RAGE and RAS system; RAGE and oxidative stress.
Main body of the abstract
AD is a neurodegenerative disease characterized by cognitive dysfunction and neuronal cell death. Vascular complications like hypertension, coronary artery disease, and atherosclerosis as well as metabolic syndromes like obesity and diabetes are related to the pathophysiology of AD. RAGE plays significant role in the onset and progression of AD. Amyloid plaques and neurofibrillary tangles (NFT) are two main markers of AD that regulates via RAGE and other RAGE/ligands interactions which also induces oxidative stress and a cascade of other cellular inflammation pathways leading to AD. Though AD and diabetes are two different disorders but may be inter-linked by AGEs and RAGE. In long-term hyperglycemia, upregulated AGEs interacts with RAGE and produces reactive oxygen species which induces further inflammation and vascular complications. Aging, hypercholesterolemia, atherosclerosis, hypertension, obesity, and inflammation are some of the main risk factors for both diabetes and dementia. Chronic hypertension and coronary artery disease disrupt the functions of the blood-brain barrier and are responsible for the accumulation of senile plaques and NFTs.
Short conclusion
RAGE plays a role in the etiology of Aβ and tau hyperphosphorylation, both of which contribute to cognitive impairment. So far, targeting RAGE may provide a potential sight to develop therapies against some metabolic disorders.
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Khan MSH, Hegde V. Obesity and Diabetes Mediated Chronic Inflammation: A Potential Biomarker in Alzheimer's Disease. J Pers Med 2020; 10:jpm10020042. [PMID: 32455946 PMCID: PMC7354630 DOI: 10.3390/jpm10020042] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 05/16/2020] [Accepted: 05/19/2020] [Indexed: 12/15/2022] Open
Abstract
Alzheimer’s disease (AD) is the sixth leading cause of death and is correlated with obesity, which is the second leading cause of preventable diseases in the United States. Obesity, diabetes, and AD share several common features, and inflammation emerges as the central link. High-calorie intake, elevated free fatty acids, and impaired endocrine function leads to insulin resistance and systemic inflammation. Systemic inflammation triggers neuro-inflammation, which eventually hinders the metabolic and regulatory function of the brain mitochondria leading to neuronal damage and subsequent AD-related cognitive decline. As an early event in the pathogenesis of AD, chronic inflammation could be considered as a potential biomarker in the treatment strategies for AD.
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Wang M, Norman JE, Srinivasan VJ, Rutledge JC. Metabolic, inflammatory, and microvascular determinants of white matter disease and cognitive decline. AMERICAN JOURNAL OF NEURODEGENERATIVE DISEASE 2016; 5:171-177. [PMID: 28078193 PMCID: PMC5218857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Received: 10/09/2016] [Accepted: 10/27/2016] [Indexed: 06/06/2023]
Abstract
White Matter Disease is increasingly being recognized as an important cause of cognitive decline and dementia. Various investigations have linked chronic diet-related conditions to the development of white matter lesions, which appear as white matter hyperintensities on T2-weighted magnetic resonance imaging (MRI) scans of the brain. Thus, it can be postulated that the metabolic, inflammatory, and microvascular changes accompanying a western diet, hyperlipidemia, hypertension, and diabetes mellitus type II (DMII) are potential mediators in the development and progression of white matter disease, which in turn contributes to the development and progression of cognitive decline. This review will examine evidence for potential metabolic, inflammatory, and microvascular determinants of white matter disease and cognitive decline. Specifically, we will focus on the effects of altered insulin signaling in diabetes, obesity-induced oxidative stress, neuroinflammation, arterial stiffness due to hypertension, ischemia secondary to cerebral small vessel disease, and blood brain barrier disturbances.
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Affiliation(s)
- Maggie Wang
- School of Medicine, University of California DavisUSA
| | - Jennifer E Norman
- Department of Internal Medicine, Division of Cardiology, University of California DavisUSA
| | | | - John C Rutledge
- Department of Internal Medicine, Division of Cardiology, University of California DavisUSA
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Gorska-Ciebiada M, Saryusz-Wolska M, Borkowska A, Ciebiada M, Loba J. Adiponectin, leptin and IL-1 β in elderly diabetic patients with mild cognitive impairment. Metab Brain Dis 2016; 31:257-66. [PMID: 26432692 PMCID: PMC4791470 DOI: 10.1007/s11011-015-9739-0] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2015] [Accepted: 09/23/2015] [Indexed: 01/07/2023]
Abstract
The aim of the study was to determine the serum levels of adiponectin, leptin and IL-1 β in elderly diabetic patients with and without mild cognitive impairment (MCI) and to examine the associations of these markers with clinical and cognitive parameters. A biochemical evaluation was performed of 62 seniors with type 2 diabetes (T2DM) and MCI, and 132 seniors with T2DM but without MCI (controls). Serum leptin and IL-1 β levels were higher and adiponectin concentration was lower in MCI patients than controls. In MCI subjects, adiponectin level was negatively correlated with leptin, IL-1 β levels and BMI. Leptin concentration was correlated with IL-1 β level. Univariate logistic regression models revealed that the factors which increased the likelihood of diagnosis of MCI in elderly patients with T2DM were higher levels of HbA1c, leptin, IL-1 β and triglycerides, as well as lower levels of adiponectin and HDL cholesterol. Similarly, previous CVD, hypertension, hyperlipidemia, retinopathy, nephropathy, hypoglycemia, longer duration of diabetes, increased number of co-morbidities, older age, fewer years of formal education were found to be associated with MCI. The multivariable model indicated fewer years of formal education, previous CVD, hypertension, increased number of co-morbidities, higher HbA1c and IL-1 β levels and lower adiponectin level. Elderly diabetic patients with MCI have higher levels of leptin and IL-1 β and lower levels of adiponectin. Further prospective studies are needed to determine the role of these markers in the progression to dementia.
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Affiliation(s)
- Malgorzata Gorska-Ciebiada
- Department of Internal Medicine and Diabetology, Medical University of Lodz, ul. Pomorska 251, 92-213, Lodz, Poland.
| | - Malgorzata Saryusz-Wolska
- Department of Internal Medicine and Diabetology, Medical University of Lodz, ul. Pomorska 251, 92-213, Lodz, Poland
| | - Anna Borkowska
- Department of Internal Medicine and Diabetology, Medical University of Lodz, ul. Pomorska 251, 92-213, Lodz, Poland
| | - Maciej Ciebiada
- Department of General and Oncological Pneumology, Medical University of Lodz, ul. Kopcinskiego 22, 90-153, Lodz, Poland
| | - Jerzy Loba
- Department of Internal Medicine and Diabetology, Medical University of Lodz, ul. Pomorska 251, 92-213, Lodz, Poland
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Gorska-Ciebiada M, Saryusz-Wolska M, Borkowska A, Ciebiada M, Loba J. C-Reactive Protein, Advanced Glycation End Products, and Their Receptor in Type 2 Diabetic, Elderly Patients with Mild Cognitive Impairment. Front Aging Neurosci 2015; 7:209. [PMID: 26578953 PMCID: PMC4625092 DOI: 10.3389/fnagi.2015.00209] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Accepted: 10/16/2015] [Indexed: 01/08/2023] Open
Abstract
OBJECTIVE The aim of the study was to evaluate serum levels of advanced glycation end products (AGEs), receptor for advanced glycation end products (RAGE), and C-reactive protein (CRP) in elderly patients with type 2 diabetes mellitus with and without mild cognitive impairment (MCI) and to determine the predictors (including AGEs, RAGE, and CRP levels) of having MCI in elderly patients with type 2 diabetes. METHODS Two hundred seventy-six diabetics elders were screened for MCI (using the Montreal Cognitive Assessment: MoCA score). Data of biochemical parameters and biomarkers were collected. RESULTS Serum AGEs, RAGE, and CRP levels were significantly increased in MCI patients compared to controls. In group of patients with MCI, serum RAGE level was positively correlated with AGEs level and with CRP level. RAGE, AGEs, and CRP concentrations were positively correlated with HbA1c levels and negatively correlated with MoCA score. The univariate logistic regression models revealed that variables, which increased the likelihood of diagnosis of MCI in elderly patients with type 2 diabetes were higher levels of HbA1c, RAGE, AGEs, CRP, TG, lower level of HDL cholesterol, previous CVD, HA, or use of HA drugs, hyperlipidemia, retinopathy, nephropathy, increased number of co-morbidities, older age, and less years of formal education. HA or use of HA drugs, previous CVD, higher level of RAGE and CRP, older age and less years of formal education are the factors increasing the likelihood of having MCI in elderly patients with type 2 diabetes in multivariable model. CONCLUSION In summary, serum AGEs, RAGE, and CRP are increased in the circulation of MCI elderly diabetic patients compared to controls. A larger population-based prospective study needs to be performed to further confirm the relationship between AGEs, RAGE, and the cognitive decline or progress to dementia.
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Affiliation(s)
| | | | - Anna Borkowska
- Department of Internal Medicine and Diabetology, Medical University of Lodz , Lodz , Poland
| | - Maciej Ciebiada
- Department of General and Oncological Pneumology, Medical University of Lodz , Lodz , Poland
| | - Jerzy Loba
- Department of Internal Medicine and Diabetology, Medical University of Lodz , Lodz , Poland
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Kamal MA, Priyamvada S, Anbazhagan AN, Jabir NR, Tabrez S, Greig NH. Linking Alzheimer's disease and type 2 diabetes mellitus via aberrant insulin signaling and inflammation. CNS & NEUROLOGICAL DISORDERS DRUG TARGETS 2014; 13:338-46. [PMID: 24074448 PMCID: PMC5947865 DOI: 10.2174/18715273113126660137] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/01/2013] [Revised: 03/16/2013] [Accepted: 04/02/2013] [Indexed: 12/11/2022]
Abstract
Alzheimer's disease (AD) and type 2 diabetes mellitus (T2DM) are two progressive and devastating health disorders afflicting millions of people worldwide. The probability and incidence of both have increased considerably in recent years consequent to increased longevity and population growth. Progressively more links are being continuously found between inflammation and central nervous system disorders like AD, Parkinson's disease, Huntington's disease, motor neuron disease, multiple sclerosis, stroke, traumatic brain injury and even cancers of the nervous tissue. The depth of the relationship depends on the timing and extent of anti- or pro-inflammatory gene expression. Inflammation has also been implicated in T2DM. Misfolding and fibrillization (of tissue specific and/or non-specific proteins) are features common to both AD and T2DM and are induced by as well as contribute to inflammation and stress (oxidative/ glycation). This review appraises the roles of inflammation and abnormalities in the insulin signaling system as important shared features of T2DM and AD. The capacity of anti-cholinesterases in reducing the level of certain common inflammatory markers in particular if they may provide therapeutic potential to mitigate awry mechanisms leading to AD.
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Affiliation(s)
| | | | | | | | | | - Nigel H Greig
- Metabolomics & Enzymology Unit, Fundamental and Applied Biology Group, King Fahd Medical Research Center, King Abdulaziz University, P.O. Box 80216, Jeddah 21589, Saudi Arabia.
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Natural Compounds (Small Molecules) as Potential and Real Drugs of Alzheimer's Disease. ACTA ACUST UNITED AC 2014. [DOI: 10.1016/b978-0-444-63281-4.00006-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
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9
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Hayden M, Banks W, Shah G, Gu Z, Sowers J. Cardiorenal metabolic syndrome and diabetic cognopathy. Cardiorenal Med 2013; 3:265-82. [PMID: 24474955 PMCID: PMC3901619 DOI: 10.1159/000357113] [Citation(s) in RCA: 16] [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: 07/19/2013] [Accepted: 11/01/2013] [Indexed: 12/22/2022] Open
Abstract
The prevalence of the cardiorenal metabolic syndrome (CRS) is increasing in parallel with obesity, type 2 diabetes mellitus, Alzheimer's disease, and other forms of dementia. Along with metabolic, inflammatory, and immunological abnormalities, there is maladaptive structural remodeling of the heart, kidney, and brain. The term 'diabetic cognopathy' (DC) may be used when discussing functional and structural changes in the brain of the diabetic patient. DC likely represents an advanced form of these changes in the brain that evolve with increasing duration of the CRS and subsequent clinical diabetes. We posit that DC develops due to a convergence of aging, genetic and lifestyle abnormalities (overnutrition and lack of exercise), which result in multiple injurious metabolic and immunologic toxicities such as dysfunctional immune responses, oxidative stress, inflammation, insulin resistance, and dysglycemia (systemically and in the brain). These converging abnormalities may lead to endothelial blood-brain barrier tight junction/adherens junction (TJ/AJ) complex remodeling and microglia activation, which may result in neurodegeneration, impaired cognition, and dementia. Herein, we describe the brain ultrastructural changes evolving from a normal state to maladaptive remodeling in rodent models of CRS including microglia activation/polarization and attenuation and/or loss of the TJ/AJ complexes, pericytes and astrocytes of the neurovascular unit. Further, we discuss the potential relationship between these structural changes and the development of DC, potential therapeutic strategies, and future directions.
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Affiliation(s)
- M.R. Hayden
- Division of Endocrinology, Diabetes and Metabolism, Department of Internal Medicine, Mo., USA
- Diabetes and Cardiovascular Research Lab, University of Missouri, Mo., USA
| | - W.A. Banks
- Geriatrics Research Education and Clinical Center, Veterans Affairs Puget Sound Health Care System, Division of Geriatric Medicine, Department of Medicine, University of Washington, Seattle, Wash., USA
| | - G.N. Shah
- Division of Endocrinology, Department of Internal Medicine, Saint Louis University, St. Louis, Mo., USA
| | - Z. Gu
- Diabetes and Cardiovascular Research Lab, University of Missouri, Mo., USA
| | - J.R. Sowers
- Division of Endocrinology, Diabetes and Metabolism, Department of Internal Medicine, Mo., USA
- Diabetes and Cardiovascular Research Lab, University of Missouri, Mo., USA
- Department of Medical Pharmacology and Physiology, University of Missouri, Mo., USA
- Harry S. Truman Memorial Veterans Hospital, Columbia, Mo., USA
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Stookey JD, Klein A, Hamer J, Chi C, Higa A, Ng V, Arieff A, Kuypers FA, Larkin S, Perrier E, Lang F. RBC deformability and amino acid concentrations after hypo-osmotic challenge may reflect chronic cell hydration status in healthy young men. Physiol Rep 2013; 1:e00117. [PMID: 24303184 PMCID: PMC3841048 DOI: 10.1002/phy2.117] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Revised: 09/16/2013] [Accepted: 09/19/2013] [Indexed: 12/14/2022] Open
Abstract
Biomarkers of chronic cell hydration status are needed to determine whether chronic hyperosmotic stress increases chronic disease risk in population-representative samples. In vitro, cells adapt to chronic hyperosmotic stress by upregulating protein breakdown to counter the osmotic gradient with higher intracellular amino acid concentrations. If cells are subsequently exposed to hypo-osmotic conditions, the adaptation results in excess cell swelling and/or efflux of free amino acids. This study explored whether increased red blood cell (RBC) swelling and/or plasma or urine amino acid concentrations after hypo-osmotic challenge might be informative about relative chronic hyperosmotic stress in free-living men. Five healthy men (20-25 years) with baseline total water intake below 2 L/day participated in an 8-week clinical study: four 2-week periods in a U-shaped A-B-C-A design. Intake of drinking water was increased by +0.8 ± 0.3 L/day in period 2, and +1.5 ± 0.3 L/day in period 3, and returned to baseline intake (0.4 ± 0.2 L/day) in period 4. Each week, fasting blood and urine were collected after a 750 mL bolus of drinking water, following overnight water restriction. The periods of higher water intake were associated with significant decreases in RBC deformability (index of cell swelling), plasma histidine, urine arginine, and urine glutamic acid. After 4 weeks of higher water intake, four out of five participants had ½ maximal RBC deformability below 400 mmol/kg; plasma histidine below 100 μmol/L; and/or undetectable urine arginine and urine glutamic acid concentrations. Work is warranted to pursue RBC deformability and amino acid concentrations after hypo-osmotic challenge as possible biomarkers of chronic cell hydration.
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Affiliation(s)
- Jodi D Stookey
- Children's Hospital Oakland Research Institute Oakland, California
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Ramanan VK, Saykin AJ. Pathways to neurodegeneration: mechanistic insights from GWAS in Alzheimer's disease, Parkinson's disease, and related disorders. AMERICAN JOURNAL OF NEURODEGENERATIVE DISEASE 2013; 2:145-175. [PMID: 24093081 PMCID: PMC3783830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Received: 07/11/2013] [Accepted: 08/25/2013] [Indexed: 06/02/2023]
Abstract
The discovery of causative genetic mutations in affected family members has historically dominated our understanding of neurodegenerative diseases such as Alzheimer's disease (AD), Parkinson's disease (PD), frontotemporal dementia (FTD), and amyotrophic lateral sclerosis (ALS). Nevertheless, most cases of neurodegenerative disease are not explained by Mendelian inheritance of known genetic variants, but instead are thought to have a complex etiology with numerous genetic and environmental factors contributing to susceptibility. Although unbiased genome-wide association studies (GWAS) have identified novel associations to neurodegenerative diseases, most of these hits explain only modest fractions of disease heritability. In addition, despite the substantial overlap of clinical and pathologic features among major neurodegenerative diseases, surprisingly few GWAS-implicated variants appear to exhibit cross-disease association. These realities suggest limitations of the focus on individual genetic variants and create challenges for the development of diagnostic and therapeutic strategies, which traditionally target an isolated molecule or mechanistic step. Recently, GWAS of complex diseases and traits have focused less on individual susceptibility variants and instead have emphasized the biological pathways and networks revealed by genetic associations. This new paradigm draws on the hypothesis that fundamental disease processes may be influenced on a personalized basis by a combination of variants - some common and others rare, some protective and others deleterious - in key genes and pathways. Here, we review and synthesize the major pathways implicated in neurodegeneration, focusing on GWAS from the most prevalent neurodegenerative disorders, AD and PD. Using literature mining, we also discover a novel regulatory network that is enriched with AD- and PD-associated genes and centered on the SP1 and AP-1 (Jun/Fos) transcription factors. Overall, this pathway- and network-driven model highlights several potential shared mechanisms in AD and PD that will inform future studies of these and other neurodegenerative disorders. These insights also suggest that biomarker and treatment strategies may require simultaneous targeting of multiple components, including some specific to disease stage, in order to assess and modulate neurodegeneration. Pathways and networks will provide ideal vehicles for integrating relevant findings from GWAS and other modalities to enhance clinical translation.
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Affiliation(s)
- Vijay K Ramanan
- Center for Neuroimaging, Department of Radiology and Imaging Sciences, Indiana University School of MedicineIndianapolis, IN, USA
- Department of Medical and Molecular Genetics, Indiana University School of MedicineIndianapolis, IN, USA
- Medical Scientist Training Program, Indiana University School of MedicineIndianapolis, IN, USA
| | - Andrew J Saykin
- Center for Neuroimaging, Department of Radiology and Imaging Sciences, Indiana University School of MedicineIndianapolis, IN, USA
- Department of Medical and Molecular Genetics, Indiana University School of MedicineIndianapolis, IN, USA
- Center for Computational Biology and Bioinformatics, Indiana University School of MedicineIndianapolis, IN, USA
- Indiana Alzheimer Disease Center, Indiana University School of MedicineIndianapolis, IN, USA
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