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Blanton H, Reddy PH, Benamar K. Chronic pain in Alzheimer's disease: Endocannabinoid system. Exp Neurol 2023; 360:114287. [PMID: 36455638 PMCID: PMC9789196 DOI: 10.1016/j.expneurol.2022.114287] [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: 08/08/2022] [Revised: 11/09/2022] [Accepted: 11/23/2022] [Indexed: 11/30/2022]
Abstract
Chronic pain, one of the most common reasons adults seek medical care, has been linked to restrictions in mobility and daily activities, dependence on opioids, anxiety, depression, sleep deprivation, and reduced quality of life. Alzheimer's disease (AD), a devastating neurodegenerative disorder (characterized by a progressive impairment of cognitive functions) in the elderly, is often co-morbid with chronic pain. AD is one of the most common neurodegenerative disorders in the aged population. The reported prevalence of chronic pain is 45.8% of the 50 million people with AD. As the population ages, the number of older people who experience AD and chronic pain will also increase. The current treatment options for chronic pain are limited, often ineffective, and have associated side effects. This review summarizes the role of the endocannabinoid system in pain, its potential role in chronic pain in AD, and addresses gaps and future directions.
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Affiliation(s)
- Henry Blanton
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, School of Medicine, Lubbock, TX 79430, USA
| | - P Hemachandra Reddy
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, School of Medicine, Lubbock, TX 79430, USA; Internal Medicine Department, Texas Tech University Health Sciences Center, 3601 4th Street, Lubbock, TX 79430, USA
| | - Khalid Benamar
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, School of Medicine, Lubbock, TX 79430, USA.
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Rahman MM, Tumpa MAA, Rahaman MS, Islam F, Sutradhar PR, Ahmed M, Alghamdi BS, Hafeez A, Alexiou A, Perveen A, Ashraf GM. Emerging Promise of Therapeutic Approaches Targeting Mitochondria in Neurodegenerative Disorders. Curr Neuropharmacol 2023; 21:1081-1099. [PMID: 36927428 PMCID: PMC10286587 DOI: 10.2174/1570159x21666230316150559] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Revised: 12/05/2022] [Accepted: 12/06/2022] [Indexed: 03/18/2023] Open
Abstract
Mitochondria are critical for homeostasis and metabolism in all cellular eukaryotes. Brain mitochondria are the primary source of fuel that supports many brain functions, including intracellular energy supply, cellular calcium regulation, regulation of limited cellular oxidative capacity, and control of cell death. Much evidence suggests that mitochondria play a central role in neurodegenerative disorders (NDDs) such as Parkinson's disease, Alzheimer's disease, Huntington's disease, and amyotrophic lateral sclerosis. Ongoing studies of NDDs have revealed that mitochondrial pathology is mainly found in inherited or irregular NDDs and is thought to be associated with the pathophysiological cycle of these disorders. Typical mitochondrial disturbances in NDDs include increased free radical production, decreased ATP synthesis, alterations in mitochondrial permeability, and mitochondrial DNA damage. The main objective of this review is to highlight the basic mitochondrial problems that occur in NDDs and discuss the use mitochondrial drugs, especially mitochondrial antioxidants, mitochondrial permeability transition blockade, and mitochondrial gene therapy, for the treatment and control of NDDs.
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Affiliation(s)
- Md. Mominur Rahman
- Department of Pharmacy, Faculty of Allied Health Sciences, Daffodil International University, Dhaka, Bangladesh
| | - Mst. Afroza Alam Tumpa
- Department of Pharmacy, Faculty of Allied Health Sciences, Daffodil International University, Dhaka, Bangladesh
| | - Md. Saidur Rahaman
- Department of Pharmacy, Faculty of Allied Health Sciences, Daffodil International University, Dhaka, Bangladesh
| | - Fahadul Islam
- Department of Pharmacy, Faculty of Allied Health Sciences, Daffodil International University, Dhaka, Bangladesh
| | - Popy Rani Sutradhar
- Department of Pharmacy, Faculty of Allied Health Sciences, Daffodil International University, Dhaka, Bangladesh
| | - Muniruddin Ahmed
- Department of Pharmacy, Faculty of Allied Health Sciences, Daffodil International University, Dhaka, Bangladesh
| | - Badrah S. Alghamdi
- Department of Physiology, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia
- Pre-Clinical Research Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia
- The Neuroscience Research Unit, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Abdul Hafeez
- Glocal School of Pharmacy, Glocal University, Mirzapur Pole, Saharanpur, Uttar Pradesh, India
| | - Athanasios Alexiou
- Department of Science and Engineering, Novel Global Community Educational Foundation, Hebersham, Australia
- AFNP Med Austria, Wien, Austria
| | - Asma Perveen
- Glocal School of Life Sciences, Glocal University, Mirzapur Pole, Saharanpur, Uttar Pradesh, India
| | - Ghulam Md. Ashraf
- Department of Medical Laboratory Sciences, College of Health Sciences, and Sharjah Institute for Medical Research, University of Sharjah, Sharjah, 27272, United Arab Emirates
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Kshirsagar S, Alvir RV, Pradeepkiran JA, Hindle A, Vijayan M, Ramasubramaniam B, Kumar S, Reddy AP, Reddy PH. A Combination Therapy of Urolithin A+EGCG Has Stronger Protective Effects Than Single Drug Urolithin A in a Humanized Amyloid Beta Knockin Mice for Late-Onset Alzheimer’s Disease. Cells 2022; 11:cells11172660. [PMID: 36078067 PMCID: PMC9454743 DOI: 10.3390/cells11172660] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 08/23/2022] [Accepted: 08/24/2022] [Indexed: 12/03/2022] Open
Abstract
In the current study, for the first time, we study mitophagy enhancer urolithin A and a combination of urolithin A+green tea extract EGCG against human Aβ peptide-induced mitochondrial and synaptic, dendritic, inflammatory toxicities and behavioral changes in humanized homozygous amyloid beta knockin (hAbKI) mice of late-onset Alzheimer’s disease (AD). Our findings reveal significantly increased positive effects of urolithin A and a combination treatment of urolithin A+EGCG in hAbKI mice for phenotypic behavioral changes including motor coordination, locomotion/exploratory activity, spatial learning and working memory. mRNA and protein levels of mitochondrial fusion, synaptic, mitophagy and autophagy genes were upregulated, and mitochondrial fission genes are downregulated in urolithin A and combine treatment in hAbKI mice; however, the effect is stronger in combined treatment. Immunofluorescence analysis of hippocampal brain sections shows similar findings of mRNA and protein levels. Mitochondrial dysfunction is significantly reduced in both treatment groups, but a stronger reduction is observed in combined treatment. Dendritic spines and lengths are significantly increased in both treatment groups, but the effect is stronger in combined treatment. The fragmented number of mitochondria is reduced, and mitochondrial length is increased, and mitophagosomal formations are increased in both the groups, but the effect is stronger in the combined treatment. The levels of amyloid beta (Aβ) 40 and Aβ42 are reduced in both treatments, however, the reduction is higher for combined treatment. These observations suggest that urolithin A is protective against human Aβ peptide-induced toxicities; however, combined treatment of urolithin A+EGCG is effective and stronger, indicating that combined therapy is promising to treat late-onset AD patients.
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Affiliation(s)
- Sudhir Kshirsagar
- Department of Internal Medicine, Texas Tech University Health Sciences Center, 3601 4th Street, Lubbock, TX 79430, USA
| | - Rainier Vladlen Alvir
- Department of Internal Medicine, Texas Tech University Health Sciences Center, 3601 4th Street, Lubbock, TX 79430, USA
| | - Jangampalli Adi Pradeepkiran
- Department of Internal Medicine, Texas Tech University Health Sciences Center, 3601 4th Street, Lubbock, TX 79430, USA
| | - Ashly Hindle
- Department of Internal Medicine, Texas Tech University Health Sciences Center, 3601 4th Street, Lubbock, TX 79430, USA
| | - Murali Vijayan
- Department of Internal Medicine, Texas Tech University Health Sciences Center, 3601 4th Street, Lubbock, TX 79430, USA
| | - Bhagavathi Ramasubramaniam
- Department of Internal Medicine, Texas Tech University Health Sciences Center, 3601 4th Street, Lubbock, TX 79430, USA
| | - Subodh Kumar
- Department of Internal Medicine, Texas Tech University Health Sciences Center, 3601 4th Street, Lubbock, TX 79430, USA
- Center of Emphasis in Neuroscience, Department of Molecular and Translational Medicine, Texas Tech University Health Sciences Center, El Paso, TX 79905, USA
| | - Arubala P. Reddy
- Nutritional Sciences Department, College of Human Sciences, Texas Tech University, 1301 Akron Ave, Lubbock, TX 79409, USA
| | - P. Hemachandra Reddy
- Department of Internal Medicine, Texas Tech University Health Sciences Center, 3601 4th Street, Lubbock, TX 79430, USA
- Nutritional Sciences Department, College of Human Sciences, Texas Tech University, 1301 Akron Ave, Lubbock, TX 79409, USA
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
- Department of Neurology, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
- Department of Public Health, Graduate School of Biomedical Sciences, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
- Department of Speech, Language, and Hearing Sciences, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
- Correspondence: ; Tel.: +1-806-743-3194
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Effects of pramipexole on beta-amyloid 1-42 memory deficits and evaluation of oxidative stress and mitochondrial function markers in the hippocampus of Wistar rat. Neurotoxicology 2022; 92:91-101. [PMID: 35868426 DOI: 10.1016/j.neuro.2022.07.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2021] [Revised: 07/12/2022] [Accepted: 07/13/2022] [Indexed: 12/06/2022]
Abstract
Oxidative damage and mitochondrial dysfunction are two prominent pathological features and gradually understood as important pathogenic events for neurodegenerative diseases, including aging and Alzheimer's disease (AD). The present study was aimed to explore the prolonged treatment of pramipexole (PPX) following amyloid beta (Aβ1-42)-induced cognitive deficits, oxidative stress, and mitochondrial dysfunction in Wistar rat model. We have found that PPX (1.0mg/kg, b.wt.) can rescue cognitive impairments of Aβ1-42-infused rats in Morris water maze. At the same time, PPX attenuated Aβ1-42-induced oxidative damage and increased reduced-glutathione content level, decreased lipid peroxidation rate and suppressed the activity of acetylcholinesterase and shows antioxidant effects. Additionally, PPX treatment has shown inhibition of mitochondrial reactive oxygen species production and restored mitochondrial membrane potential, oxidative phosphorylation, and enhanced ATP levels in Aβ1-42 rats. Furthermore, PPX treatment reduced bioenergetics loss and dynamics alterations by regulating PGC-1α protein level and mitigating translocation of Bax and Drp-1 to mitochondria and cytochrome-c release into the cytoplasm. PPX also increased mitofusin-2 protein expression, a basic element of mitochondrial fusion process. We conclude that remedial role of PPX in mitigating oxidative damage and mitochondrial perturbation that are modulated in Aβ1-42 rats may have the propensity in AD pathogenesis.
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Vijayan M, Yin L, Reddy PH, Benamar K. Behavioral Evidence for a Tau and HIV-gp120 Interaction. Int J Mol Sci 2022; 23:ijms23105514. [PMID: 35628323 PMCID: PMC9146203 DOI: 10.3390/ijms23105514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 05/11/2022] [Accepted: 05/12/2022] [Indexed: 12/07/2022] Open
Abstract
Despite successful virologic control with combination antiretroviral therapy (cART), about half of people living with the human immunodeficiency virus-1 (HIV) develop an HIV-associated neurocognitive disorder (HAND). It is estimated that 50% of individuals who are HIV-positive in the United States are aged 50 years or older. Therefore, a new challenge looms as individuals living with HIV increase in age. There is concern that Alzheimer’s disease (AD) may become prevalent with an earlier onset of cognitive decline in people living with HIV (PLWH). Clinical data studies reported the presence of AD biomarkers in PLWH. However, the functional significance of the interaction between HIV or HIV viral proteins and AD biomarkers is still not well studied. The main goal of the present study is to address this knowledge gap by determining if the HIV envelope glycoprotein 120 (HIV-gp120) can affect the cognitive functions in the Tau mouse AD model. Male Tau and age-matched, wild-type (WT) control mice were treated intracerebroventricularly (ICV) with HIV-gp120. The animals were evaluated for cognitive function using a Y-maze. We found that HIV-gp120 altered cognitive function in Tau mice. Notably, HIV-gp120 was able to promote a cognitive decline in transgenic Tau (P301L) mice compared to the control (HIV-gp120 and WT). We provide the first in vivo evidence of a cognitive interaction between an HIV viral protein and Tau mice.
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Affiliation(s)
- Murali Vijayan
- Internal Medicine Department, Texas Tech University Health Sciences Center, 3601 4th Street, Lubbock, TX 79430, USA; (M.V.); (P.H.R.)
| | - Linda Yin
- Garrison Institute on Aging, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA;
| | - P. Hemachandra Reddy
- Internal Medicine Department, Texas Tech University Health Sciences Center, 3601 4th Street, Lubbock, TX 79430, USA; (M.V.); (P.H.R.)
- Garrison Institute on Aging, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA;
| | - Khalid Benamar
- Department of Pharmacology and Neuroscience, School of Medicine Lubbock, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
- Correspondence: ; Tel.: +1-806-743-3570; Fax: +1-806-743-2744
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6
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Morton H, Kshirsagar S, Orlov E, Bunquin LE, Sawant N, Boleng L, George M, Basu T, Ramasubramanian B, Pradeepkiran JA, Kumar S, Vijayan M, Reddy AP, Reddy PH. Defective mitophagy and synaptic degeneration in Alzheimer's disease: Focus on aging, mitochondria and synapse. Free Radic Biol Med 2021; 172:652-667. [PMID: 34246776 DOI: 10.1016/j.freeradbiomed.2021.07.013] [Citation(s) in RCA: 74] [Impact Index Per Article: 24.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2021] [Revised: 06/06/2021] [Accepted: 07/06/2021] [Indexed: 12/12/2022]
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by memory loss and multiple cognitive impairments. AD is marked by multiple cellular changes, including deregulation of microRNAs, activation of glia and astrocytes, hormonal imbalance, defective mitophagy, synaptic degeneration, in addition to extracellular neuritic amyloid-beta (Aβ) plaques, phosphorylated tau (P-tau), and intracellular neurofibrillary tangles (NFTs). Recent research in AD revealed that defective synaptic mitophagy leads to synaptic degeneration and cognitive dysfunction in AD neurons. Our critical analyses of mitochondria and Aβ and P-tau revealed that increased levels of Aβ and P-Tau, and abnormal interactions between Aβ and Drp1, P-Tau and Drp1 induced increased mitochondrial fragmentation and proliferation of dysfunctional mitochondria in AD neurons and depleted Parkin and PINK1 levels. These events ultimately lead to impaired clearance of dead and/or dying mitochondria in AD neurons. The purpose of our article is to highlight the recent research on mitochondria and synapses in relation to Aβ and P-tau, focusing on recent developments.
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Affiliation(s)
- Hallie Morton
- Department of Internal Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, USA
| | - Sudhir Kshirsagar
- Department of Internal Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, USA
| | - Erika Orlov
- Department of Internal Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, USA
| | - Lloyd E Bunquin
- Department of Internal Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, USA
| | - Neha Sawant
- Department of Internal Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, USA
| | - Lauren Boleng
- Department of Internal Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, USA; Nutritional Sciences Nutritional Science, College of Human Sciences, Texas Tech University, 1301Akron Ave, Lubbock, TX, 79409, USA
| | - Mathew George
- Department of Internal Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, USA
| | - Tanisha Basu
- Department of Internal Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, USA
| | | | | | - Subodh Kumar
- Department of Internal Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, USA
| | - Murali Vijayan
- Department of Internal Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, USA
| | - Arubala P Reddy
- Nutritional Sciences Nutritional Science, College of Human Sciences, Texas Tech University, 1301Akron Ave, Lubbock, TX, 79409, USA
| | - P Hemachandra Reddy
- Department of Internal Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, USA; Neuroscience & Pharmacology, Texas Tech University Health Sciences Center, Lubbock, TX, USA; Neurology, Departments of School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, USA; Public Health Department of Graduate School of Biomedical Sciences, Texas Tech University Health Sciences Center, Lubbock, TX, USA; Department of Speech, Language and Hearing Sciences, School Health Professions, Texas Tech University Health Sciences Center, Lubbock, TX, USA.
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7
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John A, Reddy PH. Synaptic basis of Alzheimer's disease: Focus on synaptic amyloid beta, P-tau and mitochondria. Ageing Res Rev 2021; 65:101208. [PMID: 33157321 PMCID: PMC7770124 DOI: 10.1016/j.arr.2020.101208] [Citation(s) in RCA: 139] [Impact Index Per Article: 46.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2020] [Revised: 10/27/2020] [Accepted: 10/29/2020] [Indexed: 12/26/2022]
Abstract
Alzheimer's disease (AD) is a progressive and synaptic failure disease. Despite the many years of research, AD still harbors many secrets. As more of the world's population grows older, researchers are striving to find greater information on disease progression and pathogenesis. Identifying and treating the markers of this disease, or better yet, preventing it all together, are the hopes of those investing in this field of study. Several years of research revealed that synaptic pathology and mitochondrial oxidative damage are early events in disease progression. Loss of synapses and synaptic damage are the best correlates of cognitive deficits found in AD patients. As the disease progresses, there are significant changes at the synapse. These changes can both shed greater light onto the progression of the disease and serve as markers and therapeutic targets. This article addresses the mechanisms of synaptic action, mitochondrial regulation/dysregulation, resulting synaptic changes caused by amyloid beta and phosphorylated tau in AD progression. This article also highlights recent developments of risk factors, genetics and ApoE4 involvement, factors related to synaptic damage and loss, mislocalization of amyloid beta and phosphorylated tau, mitophagy, microglial activation and synapse-based therapies in AD. Furthermore, impairments in LTD and reactivation of microglia are discussed.
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Affiliation(s)
- Albin John
- Department of Internal Medicine, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
| | - P Hemachandra Reddy
- Department of Internal Medicine, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA; Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA; Department of Neurology, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA; Department of Public Health, Graduate School of Biomedical Sciences, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA; Department of Speech, Language, and Hearing Sciences, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA.
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8
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George EK, Reddy PH. Can Healthy Diets, Regular Exercise, and Better Lifestyle Delay the Progression of Dementia in Elderly Individuals? J Alzheimers Dis 2020; 72:S37-S58. [PMID: 31227652 DOI: 10.3233/jad-190232] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by memory loss and multiple cognitive impairments. Current healthcare costs for over 50 million people afflicted with AD are about $818 million and are projected to be $2 billion by 2050. Unfortunately, there are no drugs currently available that can delay and/or prevent the progression of disease in elderly individuals and in AD patients. Loss of synapses and synaptic damage are largely correlated with cognitive decline in AD patients. Women are at a higher lifetime risk of developing AD encompassing two-thirds of the total AD afflicted population. Only about 1-2% of total AD patients can be explained by genetic mutations in APP, PS1, and PS2 genes. Several risk factors have been identified, such as Apolipoprotein E4 genotype, type 2 diabetes, traumatic brain injury, depression, and hormonal imbalance, are reported to be associated with late-onset AD. Strong evidence reveals that antioxidant enriched diets and regular exercise reduces toxic radicals, enhances mitochondrial function and synaptic activity, and improves cognitive function in elderly populations. Current available data on the use of antioxidants in mouse models of AD and antioxidant(s) supplements in diets of elderly individuals were investigated. The use of antioxidants in randomized clinical trials in AD patients was also critically assessed. Based on our survey of current literature and findings, we cautiously conclude that healthy diets, regular exercise, and improved lifestyle can delay dementia progression and reduce the risk of AD in elderly individuals and reverse subjects with mild cognitive impairment to a non-demented state.
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Affiliation(s)
| | - P Hemachandra Reddy
- Internal Medicine Department, Texas Tech University Health Sciences Center, Lubbock, TX, USA.,Garrison Institute on Aging, Texas Tech University Health Sciences Center, Lubbock, TX, USA.,Garrison Institute on Aging, South West Campus, Texas Tech University Health Sciences Center, Lubbock, TX, USA.,Pharmacology & Neuroscience Department, Texas Tech University Health Sciences Center, Lubbock, TX, USA.,Neurology Department, Texas Tech University Health Sciences Center, Lubbock, TX, USA.,Speech, Language and Hearing Sciences Department, Texas Tech University Health Sciences Center, Lubbock, TX, USA.,Department of Public Health, Graduate School of Biomedical Sciences, Lubbock, TX, USA
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Dong YT, Cao K, Tan LC, Wang XL, Qi XL, Xiao Y, Guan ZZ. Stimulation of SIRT1 Attenuates the Level of Oxidative Stress in the Brains of APP/PS1 Double Transgenic Mice and in Primary Neurons Exposed to Oligomers of the Amyloid-β Peptide. J Alzheimers Dis 2019; 63:283-301. [PMID: 29614660 DOI: 10.3233/jad-171020] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
In the study, we examined whether the silent information regulator 1 (SIRT1) can attenuate oxidative stress in the brains of mice carrying the APP/PS1 double mutation and/or in primary neonatal rat neurons exposed to oligomers of amyloid-β peptide (AβOs). Starting at 4 or 8 months of age, the transgenic mice were treated with resveratrol (RSV, a stimulator of SIRT1) or suramin (an inhibitor) (each 20 mg/kg BW/day) for two months. The primary neurons were exposed to AβOs (0.5 μM) for 48 h and thereafter RSV (20 μM) or suramin (300 mg/ml) for 24 h. Cell viability was assessed by the CCK-8 assay; SIRT1 protein and mRNA determined by western blotting and real-time PCR, respectively; senile plaques examined immunohistochemically; ROS monitored by flow cytometry; and the contents of OH-, H2O2, O2·-, and MDA, and the activities of SOD and GSH-Px measured by standard biochemical procedures. In comparison to wild-type mice or untreated primary neurons, the expression of SIRT1 was significantly lower in the brains of APP/PS1 mice or neurons exposed to AβOs. In these same systems, increased numbers of senile plaques and a high level of oxidative stress were apparent. Interestingly, these two latter changes were attenuated by treatment with RSV, but enhanced by suramin. These findings indicate that SIRT1 may be neuroprotective.
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Affiliation(s)
- Yang-Ting Dong
- Department of Pathology at the Affiliated Hospital of Guizhou Medical University, Guiyang, P. R. China.,Key Laboratory of Endemic and Ethnic Diseases of the Ministry of Education, Guizhou Medical University, Guiyang, P. R. China
| | - Kun Cao
- Department of Pathology at the Affiliated Hospital of Guizhou Medical University, Guiyang, P. R. China.,Key Laboratory of Endemic and Ethnic Diseases of the Ministry of Education, Guizhou Medical University, Guiyang, P. R. China
| | - Long-Chun Tan
- Key Laboratory of Endemic and Ethnic Diseases of the Ministry of Education, Guizhou Medical University, Guiyang, P. R. China.,Key Laboratory of Medical Molecular Biology, Guiyang, P. R. China
| | - Xiao-Ling Wang
- Key Laboratory of Endemic and Ethnic Diseases of the Ministry of Education, Guizhou Medical University, Guiyang, P. R. China.,Key Laboratory of Medical Molecular Biology, Guiyang, P. R. China
| | - Xiao-Lan Qi
- Key Laboratory of Endemic and Ethnic Diseases of the Ministry of Education, Guizhou Medical University, Guiyang, P. R. China.,Key Laboratory of Medical Molecular Biology, Guiyang, P. R. China
| | - Yan Xiao
- Department of Pathology at the Affiliated Hospital of Guizhou Medical University, Guiyang, P. R. China.,Key Laboratory of Endemic and Ethnic Diseases of the Ministry of Education, Guizhou Medical University, Guiyang, P. R. China
| | - Zhi-Zhong Guan
- Department of Pathology at the Affiliated Hospital of Guizhou Medical University, Guiyang, P. R. China.,Key Laboratory of Endemic and Ethnic Diseases of the Ministry of Education, Guizhou Medical University, Guiyang, P. R. China.,Key Laboratory of Medical Molecular Biology, Guiyang, P. R. China
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Yang J, Long Y, Xu DM, Zhu BL, Deng XJ, Yan Z, Sun F, Chen GJ. Age- and Nicotine-Associated Gene Expression Changes in the Hippocampus of APP/PS1 Mice. J Mol Neurosci 2019; 69:608-622. [PMID: 31399937 DOI: 10.1007/s12031-019-01389-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Accepted: 07/18/2019] [Indexed: 12/17/2022]
Abstract
The etiology of Alzheimer's disease (AD) has been intensively studied. However, little is known about the molecular alterations in early-stage and late-stage AD. Hence, we performed RNA sequencing and assessed differentially expressed genes (DEGs) in the hippocampus of 18-month and 7-month-old APP/PS1 mice. Moreover, the DEGs induced by treatment with nicotine, the nicotinic acetylcholine receptor agonist that is known to improve cognition in AD, were also analyzed in old and young APP/PS1 mice. When comparing old APP/PS1 mice with their younger littermates, we found an upregulation in genes associated with calcium overload, immune response, cancer, and synaptic function; the transcripts of 14 calcium ion channel subtypes were significantly increased in aged mice. In contrast, the downregulated genes in aged mice were associated with ribosomal components, mitochondrial respiratory chain complex, and metabolism. Through comparison with DEGs in normal aging from previous reports, we found that changes in calcium channel genes remained one of the prominent features in aged APP/PS1 mice. Nicotine treatment also induced changes in gene expression. Indeed, nicotine augmented glycerolipid metabolism, but inhibited PI3K and MAPK signaling in young mice. In contrast, nicotine affected genes associated with cell senescence and death in old mice. Our study suggests a potential network connection between calcium overload and cellular signaling, in which additional nicotinic activation might not be beneficial in late-stage AD.
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Affiliation(s)
- Jie Yang
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, 1 Youyi Road, Chongqing, 400016, China
| | - Yan Long
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, 1 Youyi Road, Chongqing, 400016, China
| | - De-Mei Xu
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, 1 Youyi Road, Chongqing, 400016, China
| | - Bing-Lin Zhu
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, 1 Youyi Road, Chongqing, 400016, China
| | - Xiao-Juan Deng
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, 1 Youyi Road, Chongqing, 400016, China
| | - Zhen Yan
- Department of Physiology and Biophysics, State University of New York at Buffalo, Buffalo, NY, 14214, USA
| | - Fei Sun
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI, 48201, USA
| | - Guo-Jun Chen
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, 1 Youyi Road, Chongqing, 400016, China.
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11
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Amakiri N, Kubosumi A, Tran J, Reddy PH. Amyloid Beta and MicroRNAs in Alzheimer's Disease. Front Neurosci 2019; 13:430. [PMID: 31130840 PMCID: PMC6510214 DOI: 10.3389/fnins.2019.00430] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Accepted: 04/15/2019] [Indexed: 11/29/2022] Open
Abstract
Alzheimer's disease (AD) is a progressive mental illness characterized by memory loss and multiple cognitive impairments. In the last several decades, significant progress has been made in understanding basic biology, molecular mechanisms, and development of biomarkers and therapeutic drugs. Multiple cellular changes are implicated in the disease process including amyloid beta and phosphorylation of tau synaptic damage and mitochondrial dysfunction in AD. Among these, amyloid beta is considered a major player in the disease process. Recent advancements in molecular biology revealed that microRNAs (miRNAs) are considered potential biomarkers in AD with a focus on amyloid beta. In this article we discussed several aspects of AD including its prevalence, classifications, risk factors, and amyloid species and their accumulation in subcellular compartments. This article also discusses the discovery and biogenesis of miRNAs and their relevance to AD. Today's research continues to add to the wealth of miRNA data that has been accumulated, however, there still lacks clear-cut understanding of the physiological relevance of miRNAs to AD. MiRNAs appear to regulate translation of gene products in AD and other human diseases. However, the mechanism of how many of these miRNAs regulate both the 5' and 3'UTR of amyloid precursor protein (APP) processing is still being extrapolated. Hence, we still need more research on miRNAs and APP/amyloid beta formation in the progression and pathogenesis of AD.
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Affiliation(s)
- Nnana Amakiri
- Department of Internal Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, United States
| | - Aaron Kubosumi
- Department of Internal Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, United States
| | - James Tran
- Department of Internal Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, United States
| | - P. Hemachandra Reddy
- Department of Internal Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, United States
- Garrison Institute on Aging, Texas Tech University Health Sciences Center, Lubbock, TX, United States
- Garrison Institute on Aging, South West Campus, Texas Tech University Health Sciences Center, Lubbock, TX, United States
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX, United States
- Department Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, Lubbock, TX, United States
- Department of Neurology, Texas Tech University Health Sciences Center, Lubbock, TX, United States
- Department of Speech-Language and Hearing Clinics, Texas Tech University Health Sciences Center, Lubbock, TX, United States
- Department of Public Health, Graduate School of Biomedical Sciences, Texas Tech University Health Sciences Center, Lubbock, TX, United States
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12
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Jiang Y, Xu B, Chen J, Sui Y, Ren L, Li J, Zhang H, Guo L, Sun X. Micro-RNA-137 Inhibits Tau Hyperphosphorylation in Alzheimer's Disease and Targets the CACNA1C Gene in Transgenic Mice and Human Neuroblastoma SH-SY5Y Cells. Med Sci Monit 2018; 24:5635-5644. [PMID: 30102687 PMCID: PMC6104547 DOI: 10.12659/msm.908765] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Background Alzheimer’s disease (AD) results in cognitive impairment. The calcium voltage-gated channel subunit alpha-1 C CACNA1C gene encodes an alpha-1 C subunit of L-type calcium channel (LTCC). The aim of this study was to investigate the role of micro-RNA-137 (miR-137) and the CACNA1C gene in APPswe/PS1ΔE9 (APP/PS1) double-transgenic AD mice and in human neuroblastoma SH-SY5Y cells. Material/Methods Six-month-old APP/PS1 double-transgenic AD mice (N=6) and age-matched normal C57BL/6 mice (N=6) underwent a Morris water maze (MWM) test, expression levels of amyloid-β (Aβ), LTCC, the CACNA1C gene, and miR-137 were measured in the rat hippocampus and cerebral cortex in both groups of mice. A luciferase assay was used to evaluate the effect of miR-137 on the expression of CACNA1C in SH-SY5Y human neuroblastoma SH-SY5Y cells. Western blotting was used to detect the CACNA1C, phosphorylated-tau (p-tau), and Aβ proteins. Results In APP/PS1 transgenic AD mice, spatial learning and memory was significantly reduced, levels of Aβ1–40 and Aβ1–42 were increased in the serum, hippocampus, and cerebral cortex, expression levels of miR-137 were reduced, expression of CACNA1C protein was increased in the hippocampus and cerebral cortex, compared with normal control mice. miR-137 regulated the expression of the CACNA1C gene. Increased expression levels of p-tau (Ser202, Ser396, and Ser404) induced by Aβ1–42 were inhibited by miR-137 mimics in SH-SY5Y human neuroblastoma cells in vitro. Conclusions In a transgenic mouse model of AD, miR-137 and expression of the CACNA1C gene inhibited the hyperphosphorylation of tau protein.
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Affiliation(s)
- Yang Jiang
- Department of Neurology, The Fourth Affiliated Hospital of China Medical University, Shenyang, Liaoning, China (mainland).,Department of Neurology and Neuroscience, Shenyang First People's Hospital, Shenyang Brain Hospital, Shenyang Brain Institute, Shenyang, Liaoning, China (mainland)
| | - Bing Xu
- Department of Neurology and Neuroscience, Shenyang First People's Hospital, Shenyang Brain Hospital, Shenyang Brain Institute, Shenyang, Liaoning, China (mainland)
| | - Jing Chen
- Department of Neurology and Neuroscience, henyang Tenth People's Hospital, Shenyang Chest Hospital, Shenyang, Liaoning, China (mainland)
| | - Yi Sui
- Department of Neurology, The Fourth Affiliated Hospital of China Medical University, Shenyang, Liaoning, China (mainland).,Department of Neurology and Neuroscience, Shenyang First People's Hospital, Shenyang Brain Hospital, Shenyang Brain Institute, Shenyang, Liaoning, China (mainland)
| | - Li Ren
- Department of Neurology and Neuroscience, Shenyang First People's Hospital, Shenyang Brain Hospital, Shenyang Brain Institute, Shenyang, Liaoning, China (mainland)
| | - Jing Li
- Department of Neurology, The Fourth Affiliated Hospital of China Medical University, Shenyang, Liaoning, China (mainland)
| | - Huiyu Zhang
- Department of Neurology, The Fourth Affiliated Hospital of China Medical University, Shenyang, Liaoning, China (mainland)
| | - Liqing Guo
- Department of Neurology, The Fourth Affiliated Hospital of China Medical University, Shenyang, Liaoning, China (mainland)
| | - Xiaohong Sun
- Department of Neurology, The Fourth Affiliated Hospital of China Medical University, Shenyang, Liaoning, China (mainland)
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13
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Adams SD, Kouzani AZ, Tye SJ, Bennet KE, Berk M. An investigation into closed-loop treatment of neurological disorders based on sensing mitochondrial dysfunction. J Neuroeng Rehabil 2018; 15:8. [PMID: 29439744 PMCID: PMC5811973 DOI: 10.1186/s12984-018-0349-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Accepted: 02/05/2018] [Indexed: 12/14/2022] Open
Abstract
Dynamic feedback based closed-loop medical devices offer a number of advantages for treatment of heterogeneous neurological conditions. Closed-loop devices integrate a level of neurobiological feedback, which allows for real-time adjustments to be made with the overarching aim of improving treatment efficacy and minimizing risks for adverse events. One target which has not been extensively explored as a potential feedback component in closed-loop therapies is mitochondrial function. Several neurodegenerative and psychiatric disorders including Parkinson's disease, Major Depressive disorder and Bipolar disorder have been linked to perturbations in the mitochondrial respiratory chain. This paper investigates the potential to monitor this mitochondrial function as a method of feedback for closed-loop neuromodulation treatments. A generic model of the closed-loop treatment is developed to describe the high-level functions of any system designed to control neural function based on mitochondrial response to stimulation, simplifying comparison and future meta-analysis. This model has four key functional components including: a sensor, signal manipulator, controller and effector. Each of these components are described and several potential technologies for each are investigated. While some of these candidate technologies are quite mature, there are still technological gaps remaining. The field of closed-loop medical devices is rapidly evolving, and whilst there is a lot of interest in this area, widespread adoption has not yet been achieved due to several remaining technological hurdles. However, the significant therapeutic benefits offered by this technology mean that this will be an active area for research for years to come.
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Affiliation(s)
- Scott D. Adams
- School of Engineering, Deakin University, Geelong, VIC 3216 Australia
| | - Abbas Z. Kouzani
- School of Engineering, Deakin University, Geelong, VIC 3216 Australia
| | - Susannah J. Tye
- Department of Psychiatry and Psychology, Mayo Clinic, Rochester, MN 55905 USA
| | - Kevin E. Bennet
- Division of Engineering, Mayo Clinic, Rochester, MN 55905 USA
| | - Michael Berk
- School of Medicine, Deakin University, Waurn Ponds, VIC 3216 Australia
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14
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Reddy PH, Tonk S, Kumar S, Vijayan M, Kandimalla R, Kuruva CS, Reddy AP. A critical evaluation of neuroprotective and neurodegenerative MicroRNAs in Alzheimer's disease. Biochem Biophys Res Commun 2017; 483:1156-1165. [PMID: 27524239 PMCID: PMC5343756 DOI: 10.1016/j.bbrc.2016.08.067] [Citation(s) in RCA: 84] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Accepted: 08/10/2016] [Indexed: 12/31/2022]
Abstract
Currently, 5.4 million Americans suffer from AD, and these numbers are expected to increase up to 16 million by 2050. Despite tremendous research efforts, we still do not have drugs or agents that can delay, or prevent AD and its progression, and we still do not have early detectable biomarkers for AD. Multiple cellular changes have been implicated in AD, including synaptic damage, mitochondrial damage, production and accumulation of Aβ and phosphorylated tau, inflammatory response, deficits in neurotransmitters, deregulation of the cell cycle, and hormonal imbalance. Research into AD has revealed that miRNAs are involved in each of these cellular changes and interfere with gene regulation and translation. Recent discoveries in molecular biology have also revealed that microRNAs play a major role in post-translational regulation of gene expression. The purpose of this article is to review research that has assessed neuroprotective and neurodegenerative characteristics of microRNAs in brain samples from AD transgenic mouse models and patients with AD.
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Affiliation(s)
- P Hemachandra Reddy
- Garrison Institute on Aging Department, Texas Tech University Health Sciences Center, 3601 4th Street, MS 9424, Lubbock, TX 79430, United States; Cell Biology & Biochemistry Department, Texas Tech University Health Sciences Center, 3601 4th Street, MS 9424, Lubbock, TX 79430, United States; Neuroscience & Pharmacology Department, Texas Tech University Health Sciences Center, 3601 4th Street, MS 9424, Lubbock, TX 79430, United States; Neurology Department, Texas Tech University Health Sciences Center, 3601 4th Street, MS 9424, Lubbock, TX 79430, United States; Speech, Language and Hearing Sciences Department, Texas Tech University Health Sciences Center, 3601 4th Street, MS 9424, Lubbock, TX 79430, United States; Garrison Institute on Aging, South West Campus, Texas Tech University Health Sciences Center, 6630 S. Quaker Suite E, MS 7495, Lubbock, TX 79413, United States.
| | - Sahil Tonk
- Garrison Institute on Aging Department, Texas Tech University Health Sciences Center, 3601 4th Street, MS 9424, Lubbock, TX 79430, United States
| | - Subodh Kumar
- Garrison Institute on Aging Department, Texas Tech University Health Sciences Center, 3601 4th Street, MS 9424, Lubbock, TX 79430, United States
| | - Murali Vijayan
- Garrison Institute on Aging Department, Texas Tech University Health Sciences Center, 3601 4th Street, MS 9424, Lubbock, TX 79430, United States
| | - Ramesh Kandimalla
- Garrison Institute on Aging Department, Texas Tech University Health Sciences Center, 3601 4th Street, MS 9424, Lubbock, TX 79430, United States
| | - Chandra Sekhar Kuruva
- Garrison Institute on Aging Department, Texas Tech University Health Sciences Center, 3601 4th Street, MS 9424, Lubbock, TX 79430, United States
| | - Arubala P Reddy
- Department of Internal Medicine, Texas Tech University Health Sciences Center, 3601 Fourth Street, MS 9424, Lubbock, TX 79430, United States.
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15
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Abstract
The purpose of this mini-forum, "Neurotransmitters and Alzheimer's Disease", is to critically assess the current status of neurotransmitters in Alzheimer's disease. Neurotransmitters are essential neurochemicals that maintain synaptic and cognitive functions in mammals, including humans, by sending signals across pre- to post-synaptic neurons. Authorities in the fields of synapses and neurotransmitters of Alzheimer's disease summarize the current status of basic biology of synapses and neurotransmitters, and also update the current status of clinical trials of neurotransmitters in Alzheimer's disease. This article discusses the prevalence, economic impact, and stages of Alzheimer's dementia in humans.
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Affiliation(s)
- P. Hemachandra Reddy
- Garrison Institute on Aging, Texas Tech University Health Sciences Center, Lubbock, TX, USA
- Garrison Institute on Aging, South West Campus, Texas Tech University Health Sciences Center, Lubbock, TX, USA
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX, USA
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, Lubbock, TX, USA
- Department of Neurology, Texas Tech University Health Sciences Center, Lubbock, TX, USA
- Department of Speech, Language and Hearing Sciences, Texas Tech University Health Sciences Center, Lubbock, TX, USA
- Department of Public Health, Graduate School of Biomedical Sciences, Lubbock, TX, USA
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16
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Lu Z, Li H, Hou C, Peng Y, Long J, Liu J. Endogenously generated amyloid-β increases stiffness in human neuroblastoma cells. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2016; 46:415-424. [PMID: 27853822 DOI: 10.1007/s00249-016-1185-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Revised: 10/19/2016] [Accepted: 10/28/2016] [Indexed: 12/26/2022]
Abstract
Amyloid-β (Aβ) is widely recognized as toxic to neuronal cells. Its deposition on plasma and intracellular membranes and aggregation into amyloid plaques can disturb the composition and physiological function of neurons. Whether a physical property of cells, such as stiffness, is altered by endogenously overexpressed Aβ has not yet been investigated. In this study, we used human neuroblastoma cells stably overexpressing amyloid precursor protein (APP) and its Swedish mutant form (APPswe) to measure the changes in cell stiffness. Our results showed that the stiffness of cells overexpressing APP or APPswe was higher than that of control SH-SY5Y cells. Either reducing levels of Aβ with the γ secretase inhibitor DAPT or blocking the membrane calcium channel formed by Aβ with tromethamine decreased cell stiffness to a level close to the control SH-SY5Y cells. Our results suggested that Aβ, not APP, contributed to increased cell stiffness and that closure of calcium channels formed by Aβ can alleviate the effects of Aβ on membrane stiffness.
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Affiliation(s)
- Zhuoyang Lu
- The Key Laboratory of Biomedical Information Engineering of the Ministry of Education, Center for Mitochondrial Biology and Medicine, School of Life Science and Technology and Frontier Institute of Life Science, FIST, Xi'an Jiaotong University, 710049, Xi'an, China
| | - Hua Li
- The Key Laboratory of Biomedical Information Engineering of the Ministry of Education, Center for Mitochondrial Biology and Medicine, School of Life Science and Technology and Frontier Institute of Life Science, FIST, Xi'an Jiaotong University, 710049, Xi'an, China
| | - Chen Hou
- The Key Laboratory of Biomedical Information Engineering of the Ministry of Education, Center for Mitochondrial Biology and Medicine, School of Life Science and Technology and Frontier Institute of Life Science, FIST, Xi'an Jiaotong University, 710049, Xi'an, China
| | - Yunhua Peng
- The Key Laboratory of Biomedical Information Engineering of the Ministry of Education, Center for Mitochondrial Biology and Medicine, School of Life Science and Technology and Frontier Institute of Life Science, FIST, Xi'an Jiaotong University, 710049, Xi'an, China
| | - Jiangang Long
- The Key Laboratory of Biomedical Information Engineering of the Ministry of Education, Center for Mitochondrial Biology and Medicine, School of Life Science and Technology and Frontier Institute of Life Science, FIST, Xi'an Jiaotong University, 710049, Xi'an, China.
| | - Jiankang Liu
- The Key Laboratory of Biomedical Information Engineering of the Ministry of Education, Center for Mitochondrial Biology and Medicine, School of Life Science and Technology and Frontier Institute of Life Science, FIST, Xi'an Jiaotong University, 710049, Xi'an, China.
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17
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Huang P, Fang R, Li BY, Chen SD. Exercise-Related Changes of Networks in Aging and Mild Cognitive Impairment Brain. Front Aging Neurosci 2016; 8:47. [PMID: 27014055 PMCID: PMC4779936 DOI: 10.3389/fnagi.2016.00047] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2015] [Accepted: 02/22/2016] [Indexed: 12/12/2022] Open
Abstract
Aging and mild cognitive impairment (MCI) are accompanied by decline of cognitive functions. Meanwhile, the most common form of dementia is Alzheimer's disease (AD), which is characterized by loss of memory and other intellectual abilities serious to make difficulties for patients in their daily life. MCI is a transition period between normal aging and dementia, which has been used for early detection of emerging dementia. It converts to dementia with an annual rate of 5-15% as compared to normal aging with 1% rate. Small decreases in the conversion rate of MCI to AD might significantly reduce the prevalence of dementia. Thus, it is important to intervene at the preclinical stage. Since there are still no effective drugs to treat AD, non-drug intervention is crucial for the prevention and treatment of cognitive decline in aging and MCI populations. Previous studies have found some cognitive brain networks disrupted in aging and MCI population, and physical exercise (PE) could effectively remediate the function of these brain networks. Understanding the exercise-related mechanisms is crucial to design efficient and effective PE programs for treatment/intervention of cognitive decline. In this review, we provide an overview of the neuroimaging studies on physical training in normal aging and MCI to identify the potential mechanisms underlying current physical training procedures. Studies of functional magnetic resonance imaging, electroencephalography, magnetoencephalography and positron emission tomography on brain networks were all included. Based on our review, the default mode network, fronto-parietal network and fronto-executive network are probably the three most valuable targets for efficiency evaluation of interventions.
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Affiliation(s)
- Pei Huang
- Department of Neurology and Institute of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of MedicineShanghai, China
| | - Rong Fang
- Department of Neurology, Ruijin Hospital and Ruijin Hospital North, Shanghai Jiao Tong University School of MedicineShanghai, China
| | - Bin-Yin Li
- Department of Neurology and Institute of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of MedicineShanghai, China
| | - Sheng-Di Chen
- Department of Neurology and Institute of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of MedicineShanghai, China
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18
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Deficit of RACK1 contributes to the spatial memory impairment via upregulating BECLIN1 to induce autophagy. Life Sci 2016; 151:115-121. [PMID: 26930371 DOI: 10.1016/j.lfs.2016.02.014] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Revised: 12/14/2015] [Accepted: 02/05/2016] [Indexed: 11/21/2022]
Abstract
AIMS Deficiency of activated C kinase1 (RACK1) in the brain of aging animal and Alzheimer's disease was characterized by cognitive dementia and spatial memory impairment. However, the correlation between the RACK1 and spatial memory impairment and the mechanism involved in it remains unknown. MAIN METHODS Spatial memory impairment was performed in mice by lateral ventricle injection of Aβ25-35 (n=16, 10μl) and intraperitoneal injection of scopolamine (n=16, 10ml/kg). After the Morris water maze (MWM) which was performed to determine the ability of learning and memory in mice, expression of RACK1 was tested and the damage of hippocampus was confirmed by histopathology test. ShRACK1 was then used to decrease the level of RACK1 in hippocampus to test the ability of learning and memory and histopathology changes in hippocampus. To look into the mechanism of RACK1 on spatial memory impairment, we further measured the expression of autophagy proteins BECLIN1 and LC3-II/I in hippocampus of all mice. KEY FINDINGS Both the Aβ25-35, scopolamine impaired the spatial memory in mice (for escape latency, P=0.0004, P<0.0001) and severely damaged hippocampal DG neurons (P=0.012, P=0.014). The expression of RACK1 was significantly decreased which was concomitant with elevated BECLIN1 and LC3-II/I (P<0.001). Suppression of RACK1 by ShRACK1 plasmid (shGnb2l1) significantly impaired the spatial memory in mice, damaged hippocampal DG neurons (P=0.013), and increased the proteins of BECLIN1 and LC3-II/I (P<0.005). SIGNIFICANCE It demonstrated that the deficit of RACK1 in hippocampus impairs the ability of learning and memory in mice via up regulating autophagy.
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19
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Xu B, Gao Y, Zhan S, Xiong F, Qiu W, Qian X, Wang T, Wang N, Zhang D, Yang Q, Wang R, Bao X, Dou W, Tian R, Meng S, Gai WP, Huang Y, Yan XX, Ge W, Ma C. Quantitative protein profiling of hippocampus during human aging. Neurobiol Aging 2015; 39:46-56. [PMID: 26923401 DOI: 10.1016/j.neurobiolaging.2015.11.029] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Revised: 11/23/2015] [Accepted: 11/28/2015] [Indexed: 11/17/2022]
Abstract
The hippocampus appears commonly affected by aging and various neurologic disorders in humans, whereas little is known about age-related change in overall protein expression in this brain structure. Using the 4-plex tandem mass tag labeling, we carried out a quantitative proteomic study of the hippocampus during normal aging using postmortem brains from Chinese subjects. Hippocampal samples from 16 subjects died of non-neurological/psychiatric diseases were divided into 4 age groups: 22-49, 50-69, 70-89, and >90. Among 4582 proteins analyzed, 35 proteins were significantly elevated, whereas 25 proteins were downregulated, along with increasing age. Several upregulated proteins, including transgelin, vimentin, myosin regulatory light polypeptide 9, and calcyphosin, were further verified by quantitative Western blot analysis of hippocampal tissues from additional normal subjects. Bioinformatic analysis showed that the upregulated and downregulated proteins were largely involved in several important protein-protein interaction networks. Proteins in the electron transport chain and synaptic vesicle fusion pathway were consistently downregulated with aging, whereas proteins associated with Alzheimer's disease showed little change. Our study demonstrates substantial protein profile changes in the human hippocampus during aging, which could be of relevance to age-related loss of hippocampal functions.
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Affiliation(s)
- Benhong Xu
- National Key Laboratory of Medical Molecular Biology & Department of Immunology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, Beijing, China
| | - Yanpan Gao
- National Key Laboratory of Medical Molecular Biology & Department of Immunology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, Beijing, China
| | - Shaohua Zhan
- National Key Laboratory of Medical Molecular Biology & Department of Immunology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, Beijing, China
| | - Feng Xiong
- National Key Laboratory of Medical Molecular Biology & Department of Immunology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, Beijing, China
| | - Wenying Qiu
- Department of Human Anatomy, Histology and Embryology, Institute of Basic Medical Sciences, Neuroscience Center, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China
| | - Xiaojing Qian
- Department of Human Anatomy, Histology and Embryology, Institute of Basic Medical Sciences, Neuroscience Center, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China
| | - Tao Wang
- Department of Human Anatomy, Histology and Embryology, Institute of Basic Medical Sciences, Neuroscience Center, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China
| | - Naili Wang
- Department of Human Anatomy, Histology and Embryology, Institute of Basic Medical Sciences, Neuroscience Center, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China
| | - Di Zhang
- Department of Human Anatomy, Histology and Embryology, Institute of Basic Medical Sciences, Neuroscience Center, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China
| | - Qian Yang
- Department of Human Anatomy, Histology and Embryology, Institute of Basic Medical Sciences, Neuroscience Center, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China
| | - Renzhi Wang
- Department of Neurosurgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Xinjie Bao
- Department of Neurosurgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Wanchen Dou
- Department of Neurosurgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Rui Tian
- Department of Neurosurgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Shu Meng
- National Key Laboratory of Medical Molecular Biology & Department of Immunology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, Beijing, China
| | - Wei-Ping Gai
- Department of Surgery and Centre for Neuroscience, Flinders University School of Medicine, Bedford Park, SA, Australia
| | - Yue Huang
- School of Medical Sciences, University of New South Wales, Sydney, Australia
| | - Xiao-Xin Yan
- Department of Anatomy and Neurobiology, Central South University School of Basic Medical Science, Changsha, Hunan, China
| | - Wei Ge
- National Key Laboratory of Medical Molecular Biology & Department of Immunology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, Beijing, China.
| | - Chao Ma
- Department of Human Anatomy, Histology and Embryology, Institute of Basic Medical Sciences, Neuroscience Center, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China.
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20
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Ghanemi A, Boubertakh B. Shorter and sturdier bridges between traditional Chinese medicines and modern pharmacology. Saudi Pharm J 2015; 23:330-2. [PMID: 26106282 PMCID: PMC4475857 DOI: 10.1016/j.jsps.2014.02.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2013] [Accepted: 02/15/2014] [Indexed: 11/30/2022] Open
Affiliation(s)
- Abdelaziz Ghanemi
- Key Laboratory of Brain and Cognitive Sciences and Key Laboratory of Animal Models and Human Disease Mechanisms, Kunming Institute of Zoology, Chinese Academy of Sciences, No. 32 Jiaochang Donglu, Kunming 650223, Yunnan Province, PR China
| | - Besma Boubertakh
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, No. 24 Tongjiaxiang, Nanjing 210009, Jiangsu Province, PR China
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21
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Kumar A, Dhull DK, Mishra PS. Therapeutic potential of mGluR5 targeting in Alzheimer's disease. Front Neurosci 2015; 9:215. [PMID: 26106290 PMCID: PMC4460345 DOI: 10.3389/fnins.2015.00215] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2015] [Accepted: 05/29/2015] [Indexed: 11/13/2022] Open
Abstract
Decades of research dedicated toward Alzheimer's disease (AD) has culminated in much of the current understanding of the neurodegeneration associated with disease. However, delineating the pathophysiology and finding a possible cure for the disease is still wanting. This is in part due to the lack of knowledge pertaining to the connecting link between neurodegenerative and neuroinflammatory pathways. Consequently, the inefficacy and ill-effects of the drugs currently available for AD encourage the need for alternative and safe therapeutic intervention. In this review we highlight the potential of mGluR5, a metabotropic glutamatergic receptor, in understanding the mechanism underlying the neuronal death and neuroinflammation in AD. We also discuss the role of mGlu5 receptor in mediating the neuron-glia interaction in the disease. Finally, we discuss the potential of mGluR5 as target for treating AD.
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Affiliation(s)
- Anil Kumar
- UGC Centre of Advanced Studies, University Institute of Pharmaceutical Sciences, Panjab University Chandigarh, India
| | - Dinesh K Dhull
- UGC Centre of Advanced Studies, University Institute of Pharmaceutical Sciences, Panjab University Chandigarh, India
| | - Pooja S Mishra
- Department of Neurophysiology, National Institute of Mental Health and Neuro Sciences Bangalore, India
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22
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Renuga Parameswari A, Rajalakshmi G, Kumaradhas P. A combined molecular docking and charge density analysis is a new approach for medicinal research to understand drug-receptor interaction: curcumin-AChE model. Chem Biol Interact 2014; 225:21-31. [PMID: 25446495 DOI: 10.1016/j.cbi.2014.09.011] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Revised: 08/16/2014] [Accepted: 09/05/2014] [Indexed: 11/29/2022]
Abstract
In the present study, a molecular docking analysis has been performed on diketone form of curcumin molecule with acetylcholinesterase (AChE). The calculated lowest docked energy of curcumin molecule in the active site of AChE is -11.21 kcal/mol; this high negative value indicates that the molecule exhibits large binding affinity towards AChE. When the curcumin molecule present in the active site of AChE, subsequently, its conformation has altered significantly and the molecule adopts a U-shape geometry as it is linear in gas phase (before entering into the active site). This conformational transition facilitates curcumin to form strong interaction with Phe330 of acyl-binding pocket and the choline binding site with indole ring of Trp84 and Asp72. The gas phase and the active site analysis of curcumin allows to understand the conformational geometry, nature of molecular flexibility, charge density redistribution and the variation of electrostatic properties of curcumin in the active site. To obtain the gas phase structure, the curcumin molecule was optimized using Hartree-Fock and density functional methods (B3LYP) with the basis set 6-311G(∗∗). A charge density analysis on both gas phase as well as the molecule lifted from the active site was carried out using Bader's theory of atoms in molecules (AIM). The difference in molecular electrostatic potential between the two forms of curcumin displays the difference in charge distribution. The large dipole moment of curcumin (7.54 D) in the active site reflects the charge redistribution as it is much less in the gas phase (4.34 D).
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Affiliation(s)
- A Renuga Parameswari
- Laboratory of Biocrystallography and Computational Molecular Biology, Department of Physics, Periyar University, Salem 636 011, India
| | - G Rajalakshmi
- Laboratory of Biocrystallography and Computational Molecular Biology, Department of Physics, Periyar University, Salem 636 011, India
| | - P Kumaradhas
- Laboratory of Biocrystallography and Computational Molecular Biology, Department of Physics, Periyar University, Salem 636 011, India.
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Common mechanisms in neurodegeneration and neuroinflammation: a BrainNet Europe gene expression microarray study. J Neural Transm (Vienna) 2014; 122:1055-68. [DOI: 10.1007/s00702-014-1293-0] [Citation(s) in RCA: 92] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Accepted: 08/06/2014] [Indexed: 11/27/2022]
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Talwar P, Silla Y, Grover S, Gupta M, Agarwal R, Kushwaha S, Kukreti R. Genomic convergence and network analysis approach to identify candidate genes in Alzheimer's disease. BMC Genomics 2014; 15:199. [PMID: 24628925 PMCID: PMC4028079 DOI: 10.1186/1471-2164-15-199] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Accepted: 02/21/2014] [Indexed: 01/28/2023] Open
Abstract
Background Alzheimer’s disease (AD) is one of the leading genetically complex and heterogeneous disorder that is influenced by both genetic and environmental factors. The underlying risk factors remain largely unclear for this heterogeneous disorder. In recent years, high throughput methodologies, such as genome-wide linkage analysis (GWL), genome-wide association (GWA) studies, and genome-wide expression profiling (GWE), have led to the identification of several candidate genes associated with AD. However, due to lack of consistency within their findings, an integrative approach is warranted. Here, we have designed a rank based gene prioritization approach involving convergent analysis of multi-dimensional data and protein-protein interaction (PPI) network modelling. Results Our approach employs integration of three different AD datasets- GWL,GWA and GWE to identify overlapping candidate genes ranked using a novel cumulative rank score (SR) based method followed by prioritization using clusters derived from PPI network. SR for each gene is calculated by addition of rank assigned to individual gene based on either p value or score in three datasets. This analysis yielded 108 plausible AD genes. Network modelling by creating PPI using proteins encoded by these genes and their direct interactors resulted in a layered network of 640 proteins. Clustering of these proteins further helped us in identifying 6 significant clusters with 7 proteins (EGFR, ACTB, CDC2, IRAK1, APOE, ABCA1 and AMPH) forming the central hub nodes. Functional annotation of 108 genes revealed their role in several biological activities such as neurogenesis, regulation of MAP kinase activity, response to calcium ion, endocytosis paralleling the AD specific attributes. Finally, 3 potential biochemical biomarkers were found from the overlap of 108 AD proteins with proteins from CSF and plasma proteome. EGFR and ACTB were found to be the two most significant AD risk genes. Conclusions With the assumption that common genetic signals obtained from different methodological platforms might serve as robust AD risk markers than candidates identified using single dimension approach, here we demonstrated an integrated genomic convergence approach for disease candidate gene prioritization from heterogeneous data sources linked to AD. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-199) contains supplementary material, which is available to authorized users.
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Affiliation(s)
| | | | | | | | | | | | - Ritushree Kukreti
- Genomics and Molecular Medicine Unit, Institute of Genomics and Integrative Biology (IGIB), Council of Scientific and Industrial Research (CSIR), Mall Road, Delhi 110 007, India.
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Gatta V, D'Aurora M, Granzotto A, Stuppia L, Sensi SL. Early and sustained altered expression of aging-related genes in young 3xTg-AD mice. Cell Death Dis 2014; 5:e1054. [PMID: 24525730 PMCID: PMC3944230 DOI: 10.1038/cddis.2014.11] [Citation(s) in RCA: 38] [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: 10/16/2013] [Revised: 12/12/2013] [Accepted: 01/07/2014] [Indexed: 12/13/2022]
Abstract
Alzheimer's disease (AD) is a multifactorial neurological condition associated with a genetic profile that is still not completely understood. In this study, using a whole gene microarray approach, we investigated age-dependent gene expression profile changes occurring in the hippocampus of young and old transgenic AD (3xTg-AD) and wild-type (WT) mice. The aim of the study was to assess similarities between aging- and AD-related modifications of gene expression and investigate possible interactions between the two processes. Global gene expression profiles of hippocampal tissue obtained from 3xTg-AD and WT mice at 3 and 12 months of age (m.o.a.) were analyzed by hierarchical clustering. Interaction among transcripts was then studied with the Ingenuity Pathway Analysis (IPA) software, a tool that discloses functional networks and/or pathways associated with sets of specific genes of interest. Cluster analysis revealed the selective presence of hundreds of upregulated and downregulated transcripts. Functional analysis showed transcript involvement mainly in neuronal death and autophagy, mitochondrial functioning, intracellular calcium homeostasis, inflammatory response, dendritic spine formation, modulation of synaptic functioning, and cognitive decline. Thus, overexpression of AD-related genes (such as mutant APP, PS1, and hyperphosphorylated tau, the three genes that characterize our model) appears to favor modifications of additional genes that are involved in AD development and progression. The study also showed overlapping changes in 3xTg-AD at 3 m.o.a. and WT mice at 12 m.o.a., thereby suggesting altered expression of aging-related genes that occurs earlier in 3xTg-AD mice.
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Affiliation(s)
- V Gatta
- Functional Genetics Unit, Center of Excellence on Aging (CeSI), Chieti, Italy
- Department of Psychological Sciences, ‘G. d'Annunzio' University, Chieti, Italy
| | - M D'Aurora
- Functional Genetics Unit, Center of Excellence on Aging (CeSI), Chieti, Italy
- Department of Neuroscience and Imaging, ‘G. d'Annunzio' University, Chieti, Italy
| | - A Granzotto
- Molecular Neurology Unit, Center of Excellence on Aging (CeSI), Chieti, Italy
| | - L Stuppia
- Functional Genetics Unit, Center of Excellence on Aging (CeSI), Chieti, Italy
- Department of Psychological Sciences, ‘G. d'Annunzio' University, Chieti, Italy
| | - S L Sensi
- Department of Neuroscience and Imaging, ‘G. d'Annunzio' University, Chieti, Italy
- Molecular Neurology Unit, Center of Excellence on Aging (CeSI), Chieti, Italy
- Departments of Neurology and Pharmacology, University of California-Irvine, Irvine, CA, USA
- Institute for Memory Impairments and Neurological Disorders, University of California-Irvine, Irvine, CA, USA
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Prakash A, Kumar A. Role of nuclear receptor on regulation of BDNF and neuroinflammation in hippocampus of β-amyloid animal model of Alzheimer's disease. Neurotox Res 2013; 25:335-47. [PMID: 24277156 DOI: 10.1007/s12640-013-9437-9] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2013] [Revised: 10/27/2013] [Accepted: 10/29/2013] [Indexed: 12/16/2022]
Abstract
Peroxisome proliferator-activated receptor-γ (PPAR-γ) agonists have been reported to provide neuroprotective effects against neurodegenerative diseases. The current study was carried out to investigate the effects of chronic administration of pioglitazone, a PPAR-γ agonist, on cognitive impairment in an animal model of Alzheimer's disease induced by β-amyloid. Wistar rats received intracerebroventricular (ICV) β-amyloid (βA) application (3 nmol/3 μL), and behavioral alterations (locomotor activity and memory performance) were assessed. Animals were sacrificed immediately following the last behavioral session, and their brains were removed and dissected. Mitochondrial enzymes, oxidative parameters, inflammatory mediators (TNF-α, IL-6), caspase activity, and BDNF levels were measured in the hippocampus. ICV βA-treated rats showed a memory deficit and significantly decreased BDNF level, simultaneously, increase in mitochondrial oxidative damage and inflammatory mediators in the hippocampus. Memory impairment and oxidative damage were reversed by administration of pioglitazone (15 and 30 mg/kg). Pioglitazone also significantly restored the BDNF level and attenuated the actions of inflammatory markers in ICV βA-treated rats. However, pretreatment with PPAR-γ antagonist BADGE (15 mg/kg) with higher dose of pioglitazone significantly reversed its protective action in memory impairment in βA-treated rats, which indicates the involvement of PPAR-γ receptors mediating neuroprotective action. These results demonstrate that pioglitazone offers protection against β-amyloid-induced memory dysfunction possibly due to its antioxidant, anti-inflammatory, anti-apoptotic action and neurogenesis-like effect therefore, could have a therapeutic potential in Alzheimer's disease.
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Affiliation(s)
- Atish Prakash
- Pharmacology Division, University Institute of Pharmaceutical Sciences, Panjab University, Chandigarh, 160014, India,
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Han RW, Zhang RS, Xu HJ, Chang M, Peng YL, Wang R. Neuropeptide S enhances memory and mitigates memory impairment induced by MK801, scopolamine or Aβ₁₋₄₂ in mice novel object and object location recognition tasks. Neuropharmacology 2013; 70:261-7. [PMID: 23454528 DOI: 10.1016/j.neuropharm.2013.02.002] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2012] [Revised: 01/24/2013] [Accepted: 02/02/2013] [Indexed: 11/18/2022]
Abstract
Neuropeptide S (NPS), the endogenous ligand of NPSR, has been shown to promote arousal and anxiolytic-like effects. According to the predominant distribution of NPSR in brain tissues associated with learning and memory, NPS has been reported to modulate cognitive function in rodents. Here, we investigated the role of NPS in memory formation, and determined whether NPS could mitigate memory impairment induced by selective N-methyl-D-aspartate receptor antagonist MK801, muscarinic cholinergic receptor antagonist scopolamine or Aβ₁₋₄₂ in mice, using novel object and object location recognition tasks. Intracerebroventricular (i.c.v.) injection of 1 nmol NPS 5 min after training not only facilitated object recognition memory formation, but also prolonged memory retention in both tasks. The improvement of object recognition memory induced by NPS could be blocked by the selective NPSR antagonist SHA 68, indicating pharmacological specificity. Then, we found that i.c.v. injection of NPS reversed memory disruption induced by MK801, scopolamine or Aβ₁₋₄₂ in both tasks. In summary, our results indicate that NPS facilitates memory formation and prolongs the retention of memory through activation of the NPSR, and mitigates amnesia induced by blockage of glutamatergic or cholinergic system or by Aβ₁₋₄₂, suggesting that NPS/NPSR system may be a new target for enhancing memory and treating amnesia.
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Affiliation(s)
- Ren-Wen Han
- Key Laboratory of Preclinical Study for New Drugs of Gansu Province, Institute of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Lanzhou University, 222 Tian Shui South Road, Lanzhou 730000, PR China
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Hsiao CW, Peng TI, Peng AC, Reiter RJ, Tanaka M, Lai YK, Jou MJ. Long-term Aβ exposure augments mCa2+-independent mROS-mediated depletion of cardiolipin for the shift of a lethal transient mitochondrial permeability transition to its permanent mode in NARP cybrids: a protective targeting of melatonin. J Pineal Res 2013; 54:107-25. [PMID: 24446866 DOI: 10.1111/jpi.12004] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2012] [Accepted: 07/27/2012] [Indexed: 11/27/2022]
Abstract
Mitochondrial dysfunction is a hallmark of amyloid β-peptide (Aβ)-induced neurodegeneration of Alzheimer's disease (AD). This study investigated whether mtDNA T8993G mutation-induced complex V inhibition, clinically associated with neurological muscle weakness, ataxia, and retinitis pigmentosa (NARP), is a potential risk factor for AD and the pathological link for long-term exposure of Aβ-induced mitochondrial toxicity and apoptosis in NARP cybrids. Using noninvasive fluorescence probe-coupled laser scanning imaging microscopy and NARP cybrids harboring 98% mutant genes along with its parental 143B osteosarcoma cells, we demonstrated that Aβ-augmented mitochondrial Ca(2+) (mCa(2+))-independent mitochondrial reactive oxygen species (mROS) formation for a cardiolipin (CL, a major mitochondrial protective phospholipid)-dependent lethal modulation of the mitochondrial permeability transition (MPT). Aβ augmented not only the amount but also the propagation rate of mROS-induced mROS formation to significantly depolarize mitochondrial membrane potential (∆Ψ(m)) and reduce mCa(2+) stress. Aβ-augmented mROS oxidized and depleted CL, thereby enhances mitochondrial fission and movement retardation, which promoted the NARP-augmented lethal transient-MPT (t-MPT) to switch to its irreversible mode of permanent-MPT (p-MPT). Interestingly, melatonin, a multiple mitochondrial protector, markedly reduced Aβ-augmented mROS formation and therefore significantly reduced mROS-mediated depolarization of ∆Ψ(m), fission of mitochondria and retardation of mitochondrial movement to stabilize CL and hence the MPT. In the presence of melatonin, Aβ-promoted p-MPT was reversed to a protective t-MPT, which preserved ∆Ψ(m) and lowered elevated mCa(2+) to sublethal levels for an enhanced mCa(2+)-dependent O(2) consumption. Thus, melatonin may potentially rescue AD patients associated with NARP symptoms.
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Affiliation(s)
- Chia-Wei Hsiao
- Department of Life Science and Institute of Biotechnology, National Tsing Hua University, Hsinchu, Taiwan
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Chen Y, Tian Z, Liang Z, Sun S, Dai CL, Lee MH, LaFerla FM, Grundke-Iqbal I, Iqbal K, Liu F, Gong CX. Brain gene expression of a sporadic (icv-STZ Mouse) and a familial mouse model (3xTg-AD mouse) of Alzheimer's disease. PLoS One 2012; 7:e51432. [PMID: 23236499 PMCID: PMC3517562 DOI: 10.1371/journal.pone.0051432] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2012] [Accepted: 11/01/2012] [Indexed: 12/28/2022] Open
Abstract
Alzheimer's disease (AD) can be divided into sporadic AD (SAD) and familial AD (FAD). Most AD cases are sporadic and may result from multiple etiologic factors, including environmental, genetic and metabolic factors, whereas FAD is caused by mutations of presenilins or amyloid-β (Aβ) precursor protein (APP). A commonly used mouse model for AD is 3xTg-AD mouse, which is generated by over-expression of mutated presenilin 1, APP and tau in the brain and thus represents a mouse model of FAD. A mouse model generated by intracerebroventricular (icv) administration of streptozocin (STZ), icv-STZ mouse, shows many aspects of SAD. Despite the wide use of these two models for AD research, differences in gene expression between them are not known. Here, we compared the expression of 84 AD-related genes in the hippocampus and the cerebral cortex between icv-STZ mice and 3xTg-AD mice using a custom-designed qPCR array. These genes are involved in APP processing, tau/cytoskeleton, synapse function, apoptosis and autophagy, AD-related protein kinases, glucose metabolism, insulin signaling, and mTOR pathway. We found altered expression of around 20 genes in both mouse models, which affected each of above categories. Many of these gene alterations were consistent with what was observed in AD brain previously. The expression of most of these altered genes was decreased or tended to be decreased in the hippocampus of both mouse models. Significant diversity in gene expression was found in the cerebral cortex between these two AD mouse models. More genes related to synaptic function were dysregulated in the 3xTg-AD mice, whereas more genes related to insulin signaling and glucose metabolism were down-regulated in the icv-STZ mice. The present study provides important fundamental knowledge of these two AD mouse models and will help guide future studies using these two mouse models for the development of AD drugs.
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Affiliation(s)
- Yanxing Chen
- Department of Neurochemistry, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York, United States of America
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Molecular signatures in post-mortem brain tissue of younger individuals at high risk for Alzheimer's disease as based on APOE genotype. Mol Psychiatry 2011; 16:836-47. [PMID: 20479757 PMCID: PMC2953572 DOI: 10.1038/mp.2010.57] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Alzheimer's disease (AD) is a neurodegenerative condition characterized histopathologically by neuritic plaques and neurofibrillary tangles. The objective of this transcriptional profiling study was to identify both neurosusceptibility and intrinsic neuroprotective factors at the molecular level, not confounded by the downstream consequences of pathology. We thus studied post-mortem cortical tissue in 28 cases that were non-APOE4 carriers (called the APOE3 group) and 13 cases that were APOE4 carriers. As APOE genotype is the major genetic risk factor for late-onset AD, the former group was at low risk for development of the disease and the latter group was at high risk for the disease. Mean age at death was 42 years and none of the brains had histopathology diagnostic of AD at the time of death. We first derived interregional difference scores in expression between cortical tissue from a region relatively invulnerable to AD (primary somatosensory cortex, BA 1/2/3) and an area known to be susceptible to AD pathology (middle temporal gyrus, BA 21). We then contrasted the magnitude of these interregional differences in between-group comparisons of the APOE3 (low risk) and APOE4 (high risk) genotype groups. We identified 70 transcripts that differed significantly between the groups. These included EGFR, CNTFR, CASP6, GRIA2, CTNNB1, FKBPL, LGALS1 and PSMC5. Using real-time quantitative PCR, we validated these findings. In addition, we found regional differences in the expression of APOE itself. We also identified multiple Kyoto pathways that were disrupted in the APOE4 group, including those involved in mitochondrial function, calcium regulation and cell-cycle reentry. To determine the functional significance of our transcriptional findings, we used bioinformatics pathway analyses to demonstrate that the molecules listed above comprised a network of connections with each other, APOE, and APP and MAPT. Overall, our results indicated that the abnormalities that we observed in single transcripts and in signaling pathways were not the consequences of diagnostic plaque and tangle pathology, but preceded it and thus may be a causative link in the long molecular prodrome that results in clinical AD.
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Reddy PH, Reddy TP. Mitochondria as a therapeutic target for aging and neurodegenerative diseases. Curr Alzheimer Res 2011; 8:393-409. [PMID: 21470101 PMCID: PMC3295247 DOI: 10.2174/156720511795745401] [Citation(s) in RCA: 160] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2010] [Accepted: 11/11/2010] [Indexed: 01/14/2023]
Abstract
Mitochondria are cytoplasmic organelles responsible for life and death. Extensive evidence from animal models, postmortem brain studies of and clinical studies of aging and neurodegenerative diseases suggests that mitochondrial function is defective in aging and neurodegenerative diseases, such as Alzheimer's disease, Parkinson's disease, Huntington's disease, and amyotrophic lateral sclerosis. Several lines of research suggest that mitochondrial abnormalities, including defects in oxidative phosphorylation, increased accumulation of mitochondrial DNA defects, impaired calcium influx, accumulation of mutant proteins in mitochondria, and mitochondrial membrane potential dissipation are important cellular changes in both early and late-onset neurodegenerative diseases. Further, emerging evidence suggests that structural changes in mitochondria, including increased mitochondrial fragmentation and decreased mitochondrial fusion, are critical factors associated with mitochondrial dysfunction and cell death in aging and neurodegenerative diseases. This paper discusses research that elucidates features of mitochondria that are associated with cellular dysfunction in aging and neurodegenerative diseases and discusses mitochondrial structural and functional changes, and abnormal mitochondrial dynamics in neurodegenerative diseases. It also outlines mitochondria-targeted therapeutics in neurodegenerative diseases.
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Affiliation(s)
- P H Reddy
- Neurogenetics Laboratory, Division of Neuroscience, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006, USA.
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Lei JX, Cassone CG, Luebbert C, Liu QY. A novel neuron-enriched protein SDIM1 is down regulated in Alzheimer's brains and attenuates cell death induced by DNAJB4 over-expression in neuro-progenitor cells. Mol Neurodegener 2011; 6:9. [PMID: 21255413 PMCID: PMC3031242 DOI: 10.1186/1750-1326-6-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2010] [Accepted: 01/21/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Molecular changes in multiple biological processes contribute to the development of chronic neurodegeneration such as late onset Alzheimer's disease (LOAD). To discover how these changes are reflected at the level of gene expression, we used a subtractive transcription-based amplification of mRNA procedure to identify novel genes that have altered expression levels in the brains of Alzheimer's disease (AD) patients. Among the genes altered in expression level in AD brains was a transcript encoding a novel protein, SDIM1, that contains 146 amino acids, including a typical signal peptide and two transmembrane domains. Here we examined its biochemical properties and putative roles in neuroprotection/neurodegeneration. RESULTS QRT-PCR analysis of additional AD and control post-mortem human brains showed that the SDIM1 transcript was indeed significantly down regulated in all AD brains. SDIM1 is more abundant in NT2 neurons than astrocytes and present throughout the cytoplasm and neural processes, but not in the nuclei. In NT2 neurons, it is highly responsive to stress conditions mimicking insults that may cause neurodegeneration in AD brains. For example, SDIM1 was significantly down regulated 2 h after oxygen-glucose deprivation (OGD), though had recovered 16 h later, and also appeared significantly up regulated compared to untreated NT2 neurons. Overexpression of SDIM1 in neuro-progenitor cells improved cells' ability to survive after injurious insults and its downregulation accelerated cell death induced by OGD. Yeast two-hybrid screening and co-immunoprecipitation approaches revealed, both in vitro and in vivo, an interaction between SDIM1 and DNAJB4, a heat shock protein hsp40 homolog, recently known as an enhancer of apoptosis that also interacts with the mu opioid receptor in human brain. Overexpression of DNAJB4 alone significantly reduced cell viability and SDIM1 co-overexpression was capable of attenuating the cell death caused DNAJB4, suggesting that the binding of SDIM1 to DNAJB4 might sequester DNAJB4, thus increasing cell viability. CONCLUSION Taken together, we have identified a small membrane protein, which is down regulated in AD brains and neuronal cells exposed to injurious insults. Its ability to promote survival and its interaction with DNAJB4 suggest that it may play a very specific role in brain cell survival and/or receptor trafficking.
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Affiliation(s)
- Joy X Lei
- Neurobiology Program, Institute for Biological Sciences, National Research Council of Canada, Ottawa, Ontario, K1A 0R6, Canada.
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Blom ES, Wang Y, Skoglund L, Hansson AC, Ubaldi M, Lourdusamy A, Sommer WH, Mielke M, Hyman BT, Heilig M, Lannfelt L, Nilsson LNG, Ingelsson M. Increased mRNA Levels of TCF7L2 and MYC of the Wnt Pathway in Tg-ArcSwe Mice and Alzheimer's Disease Brain. Int J Alzheimers Dis 2010; 2011:936580. [PMID: 21234373 PMCID: PMC3014771 DOI: 10.4061/2011/936580] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2010] [Accepted: 11/24/2010] [Indexed: 11/20/2022] Open
Abstract
Several components in the Wnt pathway, including β-catenin and glycogen synthase kinase 3 beta, have been implied in AD pathogenesis. Here, mRNA brain levels from five-month-old tg-ArcSwe and nontransgenic mice were compared using Affymetrix microarray analysis. With surprisingly small overall changes, Wnt signaling was the most affected pathway with altered expression of nine genes in tg-ArcSwe mice. When analyzing mRNA levels of these genes in human brain, transcription factor 7-like 2 (TCF7L2) and v-myc myelocytomatosis viral oncogene homolog (MYC), were increased in Alzheimer's disease (AD) (P < .05). Furthermore, no clear differences in TCF7L2 and MYC mRNA were found in brains with frontotemporal lobar degeneration, suggesting that altered regulation of these Wnt-related genes could be specific to AD. Finally, mRNA levels of three neurogenesis markers were analyzed. Increased mRNA levels of dihydropyrimidinase-like 3 were observed in AD brain, suggesting that altered Wnt pathway regulation may signify synaptic rearrangement or neurogenesis.
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Affiliation(s)
- Elin S Blom
- Section of Molecular Geriatrics, Department of Public Health and Caring Sciences, Uppsala University, 751 85 Uppsala, Sweden
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Bossers K, Wirz KTS, Meerhoff GF, Essing AHW, van Dongen JW, Houba P, Kruse CG, Verhaagen J, Swaab DF. Concerted changes in transcripts in the prefrontal cortex precede neuropathology in Alzheimer's disease. ACTA ACUST UNITED AC 2010; 133:3699-723. [PMID: 20889584 DOI: 10.1093/brain/awq258] [Citation(s) in RCA: 173] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Using the Braak staging for neurofibrillary changes as an objective indicator of the progression of Alzheimer's disease, we have performed a systematic search for global gene expression changes in the prefrontal cortex during the course of Alzheimer's disease. In the prefrontal cortex, senile plaques and neurofibrillary changes start to appear around Braak stage III, allowing for the detection of changes in gene expression before, during and after the onset of Alzheimer's disease neuropathology. Two distinct patterns of tightly co-regulated groups of genes were observed: (i) an increase in expression in early Braak stages, followed by a decline in expression in later stages (the UPDOWN clusters; containing 865 genes) and (ii) a decrease in expression in early Braak stages, followed by an increase in expression in later stages (the DOWNUP clusters; containing 983 genes). The most profound changes in gene expression were detected between Braak stages II and III, just before or at the onset of plaque pathology and neurofibrillary changes in the prefrontal cortex. We also observed an increase in intracellular beta amyloid staining from Braak stages I to III and a clear decrease in Braak stages IV to VI. These data suggest a link between specific gene expression clusters and Alzheimer's disease-associated neuropathology in the prefrontal cortex. Gene ontology over-representation and functional gene network analyses indicate an increase in synaptic activity and changes in plasticity during the very early pre-symptomatic stage of the disease. In later Braak stages, the decreased expression of these genes suggests a reduction in synaptic activity that coincides with the appearance of plaque pathology and neurofibrillary changes and the clinical diagnosis of mild cognitive impairment. The interaction of the ApoE genotype with the expression levels of the genes in the UPDOWN and DOWNUP clusters demonstrates that the accelerating role of ApoE-ε4 in the progression of Alzheimer's disease is reflected in the temporal changes in gene expression presented here. Since the UPDOWN cluster contains several genes involved in amyloid precursor protein processing and beta amyloid clearance that increase in expression in parallel with increased intracellular beta amyloid load, just before the onset of plaque pathology in the prefrontal cortex, we hypothesize that the temporally orchestrated increase in genes involved in synaptic activity represents a coping mechanism against increased soluble beta amyloid levels. As these gene expression changes occur before the appearance of Alzheimer's disease-associated neuropathology, they provide an excellent starting point for the identification of new targets for the development of therapeutic strategies aimed at the prevention of Alzheimer's disease.
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Affiliation(s)
- Koen Bossers
- Neuroregeneration Group, Netherlands Institute for Neuroscience, Amsterdam, The Netherlands.
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Su YC, Hong JR. Betanodavirus B2 causes ATP depletion-induced cell death via mitochondrial targeting and complex II inhibition in vitro and in vivo. J Biol Chem 2010; 285:39801-10. [PMID: 20870718 DOI: 10.1074/jbc.m110.164988] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The betanodavirus non-structural protein B2 is a newly discovered necrotic death factor with a still unknown role in regulation of mitochondrial function. In the present study, we examined protein B2-mediated inhibition of mitochondrial complex II activity, which results in ATP depletion and thereby in a bioenergetic crisis in vitro and in vivo. Expression of protein B2 was detected early at 24 h postinfection with red-spotted grouper nervous necrosis virus in the cytoplasm. Later B2 was found in mitochondria using enhanced yellow fluorescent protein (EYFP) and immuno-EM analysis. Furthermore, the B2 mitochondrial targeting signal peptide was analyzed by serial deletion and specific point mutation. The sequence of the B2 targeting signal peptide ((41)RTFVISAHAA(50)) was identified and its presence correlated with loss of mitochondrial membrane potential in fish cells. Protein B2 also was found to dramatically inhibit complex II (succinate dehydrogenase) activity, which impairs ATP synthesis in fish GF-1 cells as well as human embryonic kidney 293T cells. Furthermore, when B2 was injected into zebrafish embryos at the one-cell stage to determine its cytotoxicity and ability to inhibit ATP synthesis, we found that B2 caused massive embryonic cell death and depleted ATP resulting in further embryonic death at 10 and 24 h post-fertilization. Taken together, our results indicate that betanodavirus protein B2-induced cell death is due to direct targeting of the mitochondrial matrix by a specific signal peptide that targets mitochondria and inhibits mitochondrial complex II activity thereby reducing ATP synthesis.
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Affiliation(s)
- Yu-Chin Su
- Laboratory of Molecular Virology and Biotechnology, Institute of Biotechnology, National Cheng Kung University, Tainan 701, Taiwan
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Reddy PH, Manczak M, Mao P, Calkins MJ, Reddy AP, Shirendeb U. Amyloid-beta and mitochondria in aging and Alzheimer's disease: implications for synaptic damage and cognitive decline. J Alzheimers Dis 2010. [PMID: 20413847 DOI: 10.3233/jad-2010-100504.] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
This article reviews the role of amyloid-beta (Abeta) and mitochondria in synaptic damage and cognitive decline found in patients with Alzheimer's disease (AD). Recent molecular, cellular, animal model, and postmortem brain studies have revealed that Abeta and mitochondrial abnormalities are key factors that cause synaptic damage and cognitive decline in AD. Abeta is reported to accumulate in subcellular compartments and to impair the normal function of neurons in AD patients. Further, recent studies using biochemical methods and electron microscopy have revealed that the accumulation of Abeta at nerve terminals affect synaptic activities, including the release of neurotransmitters and synaptic vesicles. Recent studies of the relationship between mitochondria and Abeta in AD patients suggest that in mitochondria, structural changes caused by Abeta result in increased mitochondrial fragmentation, decreased mitochondrial fusion, mitochondrial dysfunction, and synaptic damage. This paper discusses the latest research on Abeta, mitochondria, age-dependent factors of AD in the brain, and synaptic damage in AD. This paper also briefly discusses potential mitochondrial therapeutics in the treatment of patients with AD.
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Affiliation(s)
- P Hemachandra Reddy
- Neurogenetics Laboratory, Division of Neuroscience, Oregon National Primate Research Center, Beaverton, OR, USA.
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Reddy PH, Manczak M, Mao P, Calkins MJ, Reddy AP, Shirendeb U. Amyloid-beta and mitochondria in aging and Alzheimer's disease: implications for synaptic damage and cognitive decline. J Alzheimers Dis 2010; 20 Suppl 2:S499-512. [PMID: 20413847 DOI: 10.3233/jad-2010-100504] [Citation(s) in RCA: 180] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
This article reviews the role of amyloid-beta (Abeta) and mitochondria in synaptic damage and cognitive decline found in patients with Alzheimer's disease (AD). Recent molecular, cellular, animal model, and postmortem brain studies have revealed that Abeta and mitochondrial abnormalities are key factors that cause synaptic damage and cognitive decline in AD. Abeta is reported to accumulate in subcellular compartments and to impair the normal function of neurons in AD patients. Further, recent studies using biochemical methods and electron microscopy have revealed that the accumulation of Abeta at nerve terminals affect synaptic activities, including the release of neurotransmitters and synaptic vesicles. Recent studies of the relationship between mitochondria and Abeta in AD patients suggest that in mitochondria, structural changes caused by Abeta result in increased mitochondrial fragmentation, decreased mitochondrial fusion, mitochondrial dysfunction, and synaptic damage. This paper discusses the latest research on Abeta, mitochondria, age-dependent factors of AD in the brain, and synaptic damage in AD. This paper also briefly discusses potential mitochondrial therapeutics in the treatment of patients with AD.
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Affiliation(s)
- P Hemachandra Reddy
- Neurogenetics Laboratory, Division of Neuroscience, Oregon National Primate Research Center, Beaverton, OR, USA.
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Reddy PH. Mitochondrial oxidative damage in aging and Alzheimer's disease: implications for mitochondrially targeted antioxidant therapeutics. J Biomed Biotechnol 2010; 2006:31372. [PMID: 17047303 PMCID: PMC1559913 DOI: 10.1155/jbb/2006/31372] [Citation(s) in RCA: 101] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The overall aim of this article is to review current therapeutic strategies for treating AD, with a focus on mitochondrially targeted antioxidant treatments. Recent advances in molecular, cellular, and animal model studies of AD have revealed that amyloid precursor protein derivatives, including amyloid beta (A beta) monomers and oligomers, are likely key factors in tau hyperphosphorylation, mitochondrial oxidative damage, inflammatory changes, and synaptic failure in the brain tissue of AD patients. Several therapeutic strategies have been developed to treat AD, including anti-inflammatory, antioxidant, and antiamyloid approaches. Among these, mitochondrial antioxidant therapy has been found to be the most efficacious in reducing pathological changes and in not producing adverse effects; thus, mitochondrial antioxidant therapy is promising as a treatment for AD patients. However, a major limitation in applying mitochondrial antioxidants to AD treatment has been the inability of researchers to enhance antioxidant levels in mitochondria. Recently, however, there has been a breakthrough. Researchers have recently been able to promote the entry of certain antioxidants-including MitoQ, MitoVitE, MitoPBN, MitoPeroxidase, and amino acid and peptide-based SS tetrapeptides-into mitochondria, several hundred-fold more than do natural antioxidants. Once in the mitochondria, they rapidly neutralize free radicals and decrease mitochondrial toxicity. Thus, mitochondrially targeted antioxidants are promising candidates for treating AD patients.
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Affiliation(s)
- P. Hemachandra Reddy
- Neurogenetics Laboratory, Neurological Sciences
Institute, Oregon Health & Science University, 505 NW 185th
Avenue, Beaverton, OR 97006, USA
- *P. Hemachandra Reddy:
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Abstract
The human brain is a highly complex organ with remarkable energy demands. Although it represents only 2% of the total body weight, it accounts for 20% of all oxygen consumption, reflecting its high rate of metabolic activity. Mitochondria have a crucial role in the supply of energy to the brain. Consequently, their deterioration can have important detrimental consequences on the function and plasticity of neurons, and is thought to have a pivotal role in ageing and in the pathogenesis of several neurological disorders. Owing to their inherent physiological functions, mitochondria are subjected to particularly high levels of stress and have evolved specific molecular quality-control mechanisms to maintain the mitochondrial components. Here, we review some of the most recent advances in the understanding of mitochondrial stress-control pathways, with a particular focus on how defects in such pathways might contribute to neurodegenerative disease.
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Control of intracellular calcium signaling as a neuroprotective strategy. Molecules 2010; 15:1168-95. [PMID: 20335972 PMCID: PMC2847496 DOI: 10.3390/molecules15031168] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2009] [Revised: 02/05/2010] [Accepted: 03/02/2010] [Indexed: 12/13/2022] Open
Abstract
Both acute and chronic degenerative diseases of the nervous system reduce the viability and function of neurons through changes in intracellular calcium signaling. In particular, pathological increases in the intracellular calcium concentration promote such pathogenesis. Disease involvement of numerous regulators of intracellular calcium signaling located on the plasma membrane and intracellular organelles has been documented. Diverse groups of chemical compounds targeting ion channels, G-protein coupled receptors, pumps and enzymes have been identified as potential neuroprotectants. The present review summarizes the discovery, mechanisms and biological activity of neuroprotective molecules targeting proteins that control intracellular calcium signaling to preserve or restore structure and function of the nervous system. Disease relevance, clinical applications and new technologies for the identification of such molecules are being discussed.
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Role of mitochondria in neurodegenerative diseases: mitochondria as a therapeutic target in Alzheimer's disease. CNS Spectr 2009; 14:8-13; discussion 16-8. [PMID: 19890241 PMCID: PMC3056539 DOI: 10.1017/s1092852900024901] [Citation(s) in RCA: 133] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
A growing body of evidence suggests that mitochondrial abnormalities are involved in aging and in age-related neurodegenerative diseases as well as cancer, diabetes, and several other diseases known to be affected by mitochondria. Causal factors for most age-related neurodegenerative diseases-including Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis (ALS), and Friedrich ataxia (FRDA)-are largely unknown. Genetic defects are reported to cause a small number of neurodegenerative diseases, but cellular, molecular, and pathological mechanisms of disease progression and selective neuronal cell death are not understood fully in these diseases. However, based on several cellular, molecular, and animal model studies of Alzheimer's disease, Parkinson's disease, ALS, FRDA, cancer, and diabetes, aging may play a large role in cell death in these diseases. Age-dependent, mitochondrially-generated reactive oxygen species (ROS) have been identified as important factors responsible for disease progression and cell death, particularly in late-onset diseases, in which genetic mutations are not causal factors.
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Reddy PH. Amyloid beta, mitochondrial structural and functional dynamics in Alzheimer's disease. Exp Neurol 2009; 218:286-92. [PMID: 19358844 PMCID: PMC2710427 DOI: 10.1016/j.expneurol.2009.03.042] [Citation(s) in RCA: 203] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2009] [Revised: 03/24/2009] [Accepted: 03/27/2009] [Indexed: 11/29/2022]
Abstract
Mitochondria are the major source of energy for the normal functioning of brain cells. Increasing evidence suggests that the amyloid precursor protein (APP) and amyloid beta (Abeta) accumulate in mitochondrial membranes, cause mitochondrial structural and functional damage, and prevent neurons from functioning normally. Oligomeric Abeta is reported to induce intracellular Ca(2+) levels and to promote the excess accumulation of intracellular Ca(2+) into mitochondria, to induce the mitochondrial permeability transition pore to open, and to damage mitochondrial structure. Based on recent gene expression studies of APP transgenic mice and AD postmortem brains, and APP/Abeta and mitochondrial structural studies, we propose that the overexpression of APP and the increased production of Abeta may cause structural changes of mitochondria, including an increase in the production of defective mitochondria, a decrease in mitochondrial trafficking, and the alteration of mitochondrial dynamics in neurons affected by AD. This article discusses some critical issues of APP/Abeta associated with mitochondria, mitochondrial structural and functional damage, and abnormal intracellular calcium regulation in neurons from AD patients. This article also discusses the link between Abeta and impaired mitochondrial dynamics in AD.
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Affiliation(s)
- P Hemachandra Reddy
- Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, 97006, USA.
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Manczak M, Mao P, Nakamura K, Bebbington C, Park B, Reddy PH. Neutralization of granulocyte macrophage colony-stimulating factor decreases amyloid beta 1-42 and suppresses microglial activity in a transgenic mouse model of Alzheimer's disease. Hum Mol Genet 2009; 18:3876-93. [PMID: 19617638 DOI: 10.1093/hmg/ddp331] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The purpose of our study was to investigate microglia and astrocytes that are associated with human mutant amyloid precursor protein and amyloid beta (Abeta). We investigated whether the anti-granulocyte-macrophage-colony stimulating factor (GM-CSF) antibody can suppress microglial activity and decrease Abeta production in Alzheimer's disease transgenic mice (Tg2576 line). An antibody to mouse GM-CSF was introduced by intracerebroventricular (ICV) injections into the brains of 10-month-old Tg2576 male mice. We assessed the effect of several GM-CSF-associated cytokines on microglial activities and their association with Abeta using quantitative real-time RT-PCR, immunoblotting, immunohistochemistry analyses in anti-GM-CSF antibody-injected Tg2576 mice. Using sandwich ELISA technique, we measured intraneuronal Abeta in Tg2576 mice injected with GM-CSF antibody and PBS vehicle-injected control Tg2576 mice. Using double-labeling immunofluorescence analysis of intraneuronal Abeta, Abeta deposits and pro-inflammatory cytokines, we assessed the relationship between Abeta deposits and microglial markers in the Tg2576 mice, and also in the anti-GM-CSF antibody-injected Tg2576 mice. Our real-time RT-PCR analysis showed an increase in the mRNA expression of IL6, CD11c, IL1beta, CD40 and CD11b in the cerebral cortices of the Tg2576 mice compared with their littermate non-transgenic controls. Immunohistochemistry findings of microglial markers agreed with our real-time RT-PCR results. Interestingly, we found significantly decreased levels of activated microglia and Abeta deposits in anti-GM-CSF antibody-injected Tg2576 mice compared with PBS vehicle-injected Tg2576 mice. Findings from our real-time RT-PCR and immunoblotting analysis agreed with immunohistochemistry results. Our double-labeling analyses of intraneuronal Abeta and CD40 revealed that intraneuronal Abeta is associated with neuronal expression of CD40 in Tg2576 mice. Our quantitative sandwich ELISA analysis revealed decreased levels of soluble Abeta1-42 and increased levels of Abeta1-40 in Tg2576 mice injected with the anti-GM-CSF antibody, suggesting that anti-GM-CSF antibody alone decreases soluble Abeta1-42 production and suppresses microglial activity in Tg2576 mice. These findings indicating the ability of the anti-GM-CSF antibody to reduce Abeta1-42 and microglial activity in Tg2576 mice may have therapeutic implications for Alzheimer's disease.
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Affiliation(s)
- Maria Manczak
- Oregon National Primate Research Center, Beaverton, 97006, USA
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Noorbakhsh F, Overall CM, Power C. Deciphering complex mechanisms in neurodegenerative diseases: the advent of systems biology. Trends Neurosci 2009; 32:88-100. [DOI: 10.1016/j.tins.2008.10.003] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2008] [Revised: 10/08/2008] [Accepted: 10/08/2008] [Indexed: 11/28/2022]
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Fortin CF, McDonald PP, Lesur O, Fülöp T. Aging and neutrophils: there is still much to do. Rejuvenation Res 2009; 11:873-82. [PMID: 18847379 DOI: 10.1089/rej.2008.0750] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Human neutrophils are activated by a wide array of compounds through their receptors. This elicits their classical functions, such as chemotaxis, phagocytosis, and the production of reactive oxygen species (ROS). Upon stimulation, neutrophils also produce lipid and immune mediators and can present antigen through the major histocompatibility complex I (MHC-I). The age-related impairment of the classical functions of neutrophils is well described, but experimental evidence showing alterations in the production of mediators and antigen presentation with aging are lacking. This review highlights the role of neutrophils in age-related pathologies such as Alzheimer's disease, atherosclerosis, cancer, and autoimmune diseases. Furthermore, we discuss how aging potentially affects the production and release of mediators by human neutrophils in ways that may contribute to the development of these pathologies.
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Affiliation(s)
- Carl F Fortin
- Pulmonary Division, Faculty of Medicine, University of Sherbrooke, Sherbrooke, Quebec, Canada.
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Boissonneault V, Plante I, Rivest S, Provost P. MicroRNA-298 and microRNA-328 regulate expression of mouse beta-amyloid precursor protein-converting enzyme 1. J Biol Chem 2008; 284:1971-81. [PMID: 18986979 DOI: 10.1074/jbc.m807530200] [Citation(s) in RCA: 238] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
MicroRNAs (miRNAs) are key regulatory RNAs known to repress mRNA translation through recognition of specific binding sites located mainly in their 3'-untranslated region (UTR). Loss of specific miRNA control of gene expression is thus expected to underlie serious genetic diseases. Intriguingly, previous post-mortem analyses showed higher beta-amyloid precursor protein-converting enzyme (BACE) protein, but not mRNA, levels in the brain of patients that suffered from Alzheimer disease (AD). Here we also observed a loss of correlation between BACE1 mRNA and protein levels in the hippocampus of a mouse model of AD. Consistent with an impairment of miRNA-mediated regulation of BACE1 expression, these findings prompted us to investigate the regulatory role of the BACE1 3'-UTR element and the possible involvement of specific miRNAs in cultured neuronal (N2a) and fibroblastic (NIH 3T3) cells. Through various experimental approaches, we validated computational predictions and demonstrated that miR-298 and miR-328 recognize specific binding sites in the 3'-UTR of BACE1 mRNA and exert regulatory effects on BACE1 protein expression in cultured neuronal cells. Our results may provide the molecular basis underlying BACE1 deregulation in AD and offer new perspectives on the etiology of this neurological disorder.
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Affiliation(s)
- Vincent Boissonneault
- Centre de Recherche en Rhumatologie et Immunologie and Laboratory of Molecular Endocrinology, Centre Hospitalier de l'Université Laval Research Center/Centre Hospitalier Universitaire de Québec, Quebec, Quebec G1V 4G2, Canada
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Mitochondrial medicine for aging and neurodegenerative diseases. Neuromolecular Med 2008; 10:291-315. [PMID: 18566920 DOI: 10.1007/s12017-008-8044-z] [Citation(s) in RCA: 133] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2008] [Accepted: 05/22/2008] [Indexed: 12/22/2022]
Abstract
Mitochondria are key cytoplasmic organelles, responsible for generating cellular energy, regulating intracellular calcium levels, altering the reduction-oxidation potential of cells, and regulating cell death. Increasing evidence suggests that mitochondria play a central role in aging and in neurodegenerative diseases, such as Alzheimer's disease, Parkinson's disease, Huntington's disease, amyotrophic lateral sclerosis, and Freidriech ataxia. Further, several lines of evidence suggest that mitochondrial dysfunction is an early event in most late-onset neurodegenerative diseases. Biochemical and animal model studies of inherited neurodegenerative diseases have revealed that mutant proteins of these diseases are associated with mitochondria. Mutant proteins are reported to block the transport of nuclear-encoded mitochondrial proteins to mitochondria, interact with mitochondrial proteins and disrupt the electron transport chain, induce free radicals, cause mitochondrial dysfunction, and, ultimately, damage neurons. This article discusses critical issues of mitochondria causing dysfunction in aging and neurodegenerative diseases, and discusses the potential of developing mitochondrial medicine, particularly mitochondrially targeted antioxidants, to treat aging and neurodegenerative diseases.
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Knobloch M, Mansuy IM. Dendritic spine loss and synaptic alterations in Alzheimer's disease. Mol Neurobiol 2008; 37:73-82. [PMID: 18438727 DOI: 10.1007/s12035-008-8018-z] [Citation(s) in RCA: 207] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2008] [Accepted: 03/28/2008] [Indexed: 01/04/2023]
Abstract
Dendritic spines are tiny protrusions along dendrites, which constitute major postsynaptic sites for excitatory synaptic transmission. These spines are highly motile and can undergo remodeling even in the adult nervous system. Spine remodeling and the formation of new synapses are activity-dependent processes that provide a basis for memory formation. A loss or alteration of these structures has been described in patients with neurodegenerative disorders such as Alzheimer's disease (AD), and in mouse models for these disorders. Such alteration is thought to be responsible for cognitive deficits long before or even in the absence of neuronal loss, but the underlying mechanisms are poorly understood. This review will describe recent findings and discoveries on the loss or alteration of dendritic spines induced by the amyloid beta (Abeta) peptide in the context of AD.
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Affiliation(s)
- Marlen Knobloch
- Division of Psychiatry Research, University of Zurich, 8008 Zurich, Switzerland
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Abstract
Alzheimer disease (AD) is defined by progressive impairments in memory and cognition and by the presence of extracellular neuritic plaques and intracellular neurofibrillary tangles. However, oxidative stress and impaired mitochondrial function always accompany AD. Mitochondria are a major site of production of free radicals [ie, reactive oxygen species (ROS)] and primary targets of ROS. ROS are cytotoxic, and evidence of ROS-induced damage to cell membranes, proteins, and DNA in AD is overwhelming. Nevertheless, therapies based on antioxidants have been disappointing. Thus, alternative strategies are necessary. ROS also act as signaling molecules including for transcription. Thus, chronic exposure to ROS in AD could activate cascades of genes. Although initially protective, prolonged activation may be damaging. Thus, therapeutic approaches based on modulation of these gene cascades may lead to effective therapies. Genes involved in several pathways including antioxidant defense, detoxification, inflammation, etc, are induced in response to oxidative stress and in AD. However, genes that are associated with energy metabolism, which is necessary for normal brain function, are mostly down-regulated. Redox-sensitive transcription factors such as activator protein-1, nuclear factor-kappaB, specificity protein-1, and hypoxia-inducible factor are important in redox-dependent gene regulation. Peroxisome proliferators-activated receptor-gamma coactivator (PGC-1alpha) is a coactivator of several transcription factors and is a potent stimulator of mitochondrial biogenesis and respiration. Down-regulated expression of PGC-1alpha has been implicated in Huntington disease and in several Huntington disease animal models. PGC-1alpha role in regulation of ROS metabolism makes it a potential candidate player between ROS, mitochondria, and neurodegenerative diseases. This review summarizes the current progress on how oxidative stress regulates the expression of genes that might contribute to AD pathophysiology and the implications of the transcriptional modifications for AD. Finally, potential therapeutic strategies based on the updated understandings of redox state-dependent gene regulation in AD are proposed to overcome the lack of efficacy of antioxidant therapies.
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Liu QY, Lei JX, Sikorska M, Liu R. A novel brain-enriched E3 ubiquitin ligase RNF182 is up regulated in the brains of Alzheimer's patients and targets ATP6V0C for degradation. Mol Neurodegener 2008; 3:4. [PMID: 18298843 PMCID: PMC2279130 DOI: 10.1186/1750-1326-3-4] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2007] [Accepted: 02/25/2008] [Indexed: 01/28/2024] Open
Abstract
Background Alterations in multiple cellular pathways contribute to the development of chronic neurodegeneration such as a sporadic Alzheimer's disease (AD). These, in turn, involve changes in gene expression, amongst which are genes regulating protein processing and turnover such as the components of the ubiquitin-proteosome system. Recently, we have identified a cDNA whose expression was altered in AD brains. It contained an open reading frame of 247 amino acids and represented a novel RING finger protein, RNF182. Here we examined its biochemical properties and putative role in brain cells. Results RNF182 is a low abundance cytoplasmic protein expressed preferentially in the brain. Its expression was elevated in post-mortem AD brain tissue and the gene could be up regulated in vitro in cultured neurons subjected to cell death-inducing injuries. Subsequently, we have established that RNF182 protein possessed an E3 ubiquitin ligase activity and stimulated the E2-dependent polyubiquitination in vitro. Yeast two-hybrid screening, overexpression and co-precipitation approaches revealed, both in vitro and in vivo, an interaction between RNF182 and ATP6V0C, known for its role in the formation of gap junction complexes and neurotransmitter release channels. The data indicated that RNF182 targeted ATP6V0C for degradation by the ubiquitin-proteosome pathway. Overexpression of RNF182 reduced cell viability and it would appear that by itself the gene can disrupt cellular homeostasis. Conclusion Taken together, we have identified a novel brain-enriched RING finger E3 ligase, which was up regulated in AD brains and neuronal cells exposed to injurious insults. It interacted with ATP6V0C protein suggesting that it may play a very specific role in controlling the turnover of an essential component of neurotransmitter release machinery.
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Affiliation(s)
- Qing Yan Liu
- Neurobiology Program, Institute for Biological Sciences, National Research Council of Canada, Ottawa, Ontario, K1A 0R6, Canada.
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