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Al Rihani SB, Elfakhri KH, Ebrahim HY, Al-Ghraiybah NF, Alkhalifa AE, El Sayed KA, Kaddoumi A. The Usnic Acid Analogue 4-FPBUA Enhances the Blood-Brain Barrier Function and Induces Autophagy in Alzheimer's Disease Mouse Models. ACS Chem Neurosci 2024; 15:3152-3167. [PMID: 39145537 DOI: 10.1021/acschemneuro.4c00326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/16/2024] Open
Abstract
Preclinical and clinical studies have indicated that compromised blood-brain barrier (BBB) function contributes to Alzheimer's disease (AD) pathology. BBB breakdown ranged from mild disruption of tight junctions (TJs) with increased BBB permeability to chronic integrity loss, affecting transport across the BBB, reducing brain perfusion, and triggering inflammatory responses. We recently developed a high-throughput screening (HTS) assay to identify hit compounds that enhance the function of a cell-based BBB model. The HTS screen identified (S,E)-2-acetyl-6-[3-(4'-fluorobiphenyl-4-yl)acryloyl]-3,7,9-trihydroxy-8,9b-dimethyldibenzo-[b,d]furan-1(9bH)-one (4-FPBUA), a semisynthetic analogue of naturally occurring usnic acid, which protected the in vitro model against Aβ toxicity. Usnic acid is a lichen-derived secondary metabolite with a unique dibenzofuran skeleton that is commonly found in lichenized fungi of the genera Usnea. In this study, we aimed to evaluate the effect of 4-FPBUA in vitro on the cell-based BBB model function and its in vivo ability to rectify BBB function and reduce brain Aβ in two AD mouse models, namely, 5xFAD and TgSwDI. Our findings demonstrated that 4-FPBUA enhanced cell-based BBB function, increased Aβ transport across the monolayer, and reversed BBB breakdown in vivo by enhancing autophagy as an mTOR inhibitor. Induced autophagy was associated with a significant reduction in Aβ accumulation and related pathologies and improved memory function. These results underscore the potential of 4-FPBUA as a candidate for further preclinical exploration to better understand its mechanisms of action and to optimize dosing strategies. Continued research may also elucidate additional pathways through which 4-FPBUA contributed to the amelioration of BBB dysfunction in AD. Collectively, our findings supported the development of 4-FPBUA as a therapeutic agent against AD.
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Affiliation(s)
- Sweilem B Al Rihani
- Department of Drug Discovery and Development, Harrison College of Pharmacy, Pharmacy Research Building, Auburn University, Auburn, Alabama 36849, United States
| | - Khaled H Elfakhri
- School of Basic Pharmaceutical and Toxicological Sciences, College of Pharmacy, University of Louisiana at Monroe, Monroe, Louisiana 71201, United States
| | - Hassan Y Ebrahim
- School of Basic Pharmaceutical and Toxicological Sciences, College of Pharmacy, University of Louisiana at Monroe, Monroe, Louisiana 71201, United States
| | - Nour F Al-Ghraiybah
- Department of Drug Discovery and Development, Harrison College of Pharmacy, Pharmacy Research Building, Auburn University, Auburn, Alabama 36849, United States
| | - Amer E Alkhalifa
- Department of Drug Discovery and Development, Harrison College of Pharmacy, Pharmacy Research Building, Auburn University, Auburn, Alabama 36849, United States
| | - Khalid A El Sayed
- School of Basic Pharmaceutical and Toxicological Sciences, College of Pharmacy, University of Louisiana at Monroe, Monroe, Louisiana 71201, United States
| | - Amal Kaddoumi
- Department of Drug Discovery and Development, Harrison College of Pharmacy, Pharmacy Research Building, Auburn University, Auburn, Alabama 36849, United States
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Zhang Z, Luo X, Jiang L, Wu H, Tan Z. How do HCN channels play a part in Alzheimer's and Parkinson's disease? Ageing Res Rev 2024; 100:102436. [PMID: 39047878 DOI: 10.1016/j.arr.2024.102436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2024] [Revised: 07/08/2024] [Accepted: 07/18/2024] [Indexed: 07/27/2024]
Abstract
Neurodegenerative diseases like Alzheimer's and Parkinson's disease (AD and PD) are well-known, yet their underlying causes remain unclear. Recent studies have suggested that disruption of ion channels contribute to their pathogenesis. Among these channels, the hyperpolarization-activated cyclic nucleotide-gated (HCN) channels, encoded by HCN1-4 genes, are of particular interest due to their role in generating hyperpolarization-activated current (Ih), which is crucial in various neural activities impacting memory and motor functions. A growing body of evidence underscores the pivotal role of HCN in Aβ generation, glial cell function, and ischemia-induced dementia; while HCN is expressed in various regions of the basal ganglia, modulating their functions and influencing motor disorders in PD; neuroinflammation triggered by microglial activation represents a shared pathological mechanism in both AD and PD, in which HCN also plays a significant part. This review delves into the neuronal functions governed by HCN, its roles in the aforementioned pathogenesis, its expression patterns in AD and PD, and discusses potential therapeutic drugs targeting HCN for the treatment of these diseases, aiming to offer a novel perspective and inspire future research endeavors.
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Affiliation(s)
- Zhuo Zhang
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha 410008, PR China; Hunan Key Laboratory of Pharmacogenetics, Institute of Clinical Pharmacology, Central South University, Changsha 410078, PR China; Engineering Research Center of Applied Technology of Pharmacogenomics, Ministry of Education, Changsha 410078, PR China; National Clinical Research Center for Geriatric Disorders, Changsha 410008, PR China; Changsha Taihe Hospital, Changsha 410000, PR China; Hunan Key Laboratory for Bioanalysis of Complex Matrix Samples, Changsha 410205, PR China
| | - Xin Luo
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha 410008, PR China; Hunan Key Laboratory of Pharmacogenetics, Institute of Clinical Pharmacology, Central South University, Changsha 410078, PR China; Engineering Research Center of Applied Technology of Pharmacogenomics, Ministry of Education, Changsha 410078, PR China; National Clinical Research Center for Geriatric Disorders, Changsha 410008, PR China; Changsha Taihe Hospital, Changsha 410000, PR China; Hunan Key Laboratory for Bioanalysis of Complex Matrix Samples, Changsha 410205, PR China
| | - Liping Jiang
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha 410008, PR China; Hunan Key Laboratory of Pharmacogenetics, Institute of Clinical Pharmacology, Central South University, Changsha 410078, PR China; Engineering Research Center of Applied Technology of Pharmacogenomics, Ministry of Education, Changsha 410078, PR China; National Clinical Research Center for Geriatric Disorders, Changsha 410008, PR China; Department of Physiology, Basic Medical School, Hengyang Medical College, The Neuroscience Institute, University of South China, Hengyang 421001, PR China; Changsha Taihe Hospital, Changsha 410000, PR China; Hunan Key Laboratory for Bioanalysis of Complex Matrix Samples, Changsha 410205, PR China
| | - Huilan Wu
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha 410008, PR China; Hunan Key Laboratory of Pharmacogenetics, Institute of Clinical Pharmacology, Central South University, Changsha 410078, PR China; Engineering Research Center of Applied Technology of Pharmacogenomics, Ministry of Education, Changsha 410078, PR China; National Clinical Research Center for Geriatric Disorders, Changsha 410008, PR China; Changsha Taihe Hospital, Changsha 410000, PR China; Hunan Key Laboratory for Bioanalysis of Complex Matrix Samples, Changsha 410205, PR China
| | - Zhirong Tan
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha 410008, PR China; Hunan Key Laboratory of Pharmacogenetics, Institute of Clinical Pharmacology, Central South University, Changsha 410078, PR China; Engineering Research Center of Applied Technology of Pharmacogenomics, Ministry of Education, Changsha 410078, PR China; National Clinical Research Center for Geriatric Disorders, Changsha 410008, PR China; Changsha Taihe Hospital, Changsha 410000, PR China; Hunan Key Laboratory for Bioanalysis of Complex Matrix Samples, Changsha 410205, PR China.
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3
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Sun X, Wu X, Yang M, Deng Y, Jia B, Zhang X, Zhang M, Pi C, Bureau C, Caligiuri G, Miao Z. Comprehensive Assessment of Drug Kinetics, Neurotoxicity, and Safety of Sirolimus-Eluting Intracranial Stents in Canine Basilar Artery. Neurosurgery 2024:00006123-990000000-01275. [PMID: 38984822 DOI: 10.1227/neu.0000000000003079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2023] [Accepted: 04/30/2024] [Indexed: 07/11/2024] Open
Abstract
BACKGROUND AND OBJECTIVES Sirolimus-eluting stents (SESs) have shown promise in treating intracranial atherosclerosis but concerns about potential neurotoxicity due to prolonged drug release exist. The aim of this study was to comprehensively assess the safety of SES, with a focus on neurotoxicity. METHODS Stents (1.50 × 7 or 12 mm) were implanted into the basilar arteries of 154 Labrador Retrievers (weighing >25 kg and aged older than 1 year) divided into 4 groups: baer-metal stent, polymer-coated stent, standard-dose SES (sirolimus dose: 71 μg), and high-dose SES group (sirolimus dose: 284 μg). Pharmacokinetic analysis was conducted using liquid chromatography-mass spectrometry on blood and tissue samples, and analysis of brain tissue was performed with 5 different special stains and immunohistochemistry protocols to assess axonal degeneration, vacuolization, astrocyte proliferation, microglial activation, or widespread neurodegeneration. RESULTS In the standard-dose SES group, the stent released 10.56% of the drug on day 1 and 95.41% on day 28 postimplantation. In the high-dose SES group, corresponding figures were 40.20% on day 1 and 98.08% on day 28. Systemic drug concentration consistently remained below 1.5 ng/mL throughout the study. Arterial tissue concentration reached its peak at day 28 days in the standard-dose group and at 7 days in the high-dose group. Importantly, the brain and related tissue concentrations remained below 0.4 µg/g in both standard-dose and high-dose SES groups, peaking on day 21 in the standard-dose group and day 1 in the high-dose group. The detailed 180-day safety assessment revealed no adverse effects on the brain, even at high sirolimus doses in the SES group. CONCLUSION This study provides robust evidence supporting the long-term pharmacokinetic safety of SESs in the context of intracranial interventions for high-grade intracranial atherosclerosis. The results adequately alleviate concerns related to neurotoxicity and substantiate the feasibility of using these stents as a therapeutic choice in neurosurgery.
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Affiliation(s)
- Xuan Sun
- Interventional Neuroradiology, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
- China National Clinical Research Center for Neurological Diseases, Beijing, China
| | - Xiaojin Wu
- Sino Medical Sciences Technology Inc. (Sinomed), Tianjin, China
| | - Ming Yang
- Interventional Neuroradiology, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
- China National Clinical Research Center for Neurological Diseases, Beijing, China
| | - Yiming Deng
- Interventional Neuroradiology, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
- China National Clinical Research Center for Neurological Diseases, Beijing, China
| | - Baixue Jia
- Interventional Neuroradiology, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
- China National Clinical Research Center for Neurological Diseases, Beijing, China
| | - Xuelei Zhang
- Department of Cerebrovascular Disease, Beijing Anzhen Hospital, Capital Medical University, Beijing, China
| | - Min Zhang
- Sino Medical Sciences Technology Inc. (Sinomed), Tianjin, China
| | - Chaoqiong Pi
- Sino Medical Sciences Technology Inc. (Sinomed), Tianjin, China
| | | | - Giuseppina Caligiuri
- Department of Cardiology, Université Paris Cité, Laboratory for Vascular Translational Science, INSERM U1148, Bichat University Hospital, Paris, France
| | - Zhongrong Miao
- Interventional Neuroradiology, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
- China National Clinical Research Center for Neurological Diseases, Beijing, China
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Yan H, Wang W, Cui T, Shao Y, Li M, Fang L, Feng L. Advances in the Understanding of the Correlation Between Neuroinflammation and Microglia in Alzheimer's Disease. Immunotargets Ther 2024; 13:287-304. [PMID: 38881647 PMCID: PMC11180466 DOI: 10.2147/itt.s455881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2024] [Accepted: 06/05/2024] [Indexed: 06/18/2024] Open
Abstract
Alzheimer's disease (AD) is a fatal neurodegenerative disease with a subtle and progressive onset and is the most common type of dementia. However, its etiology and pathogenesis have not yet been fully elucidated. The common pathological manifestations of AD include extraneuronal β-amyloid deposition (Aβ), intraneuronal tau protein phosphorylation leading to the formation of 'neurofibrillary tangles' (NFTs), neuroinflammation, progressive loss of brain neurons/synapses, and glucose metabolism disorders. Current treatment approaches for AD primarily focus on the 'Aβ cascade hypothesis and abnormal aggregation of hyperphosphorylation of tau proteins', but have shown limited efficacy. Therefore, there is an ongoing need to identify more effective treatment targets for AD. The central nervous system (CNS) inflammatory response plays a key role in the occurrence and development of AD. Neuroinflammation is an immune response activated by glial cells in the CNS that usually occurs in response to stimuli such as nerve injury, infection and toxins or in response to autoimmunity. Neuroinflammation ranks as the third most prominent pathological feature in AD, following Aβ and NFTs. In recent years, the focus on the role of neuroinflammation and microglia in AD has increased due to the advancements in genome-wide association studies (GWAS) and sequencing technology. Furthermore, research has validated the pivotal role of microglia-mediated neuroinflammation in the progression of AD. Therefore, this article reviews the latest research progress on the role of neuroinflammation triggered by microglia in AD in recent years, aiming to provide a new theoretical basis for further exploring the role of neuroinflammation in the process of AD occurrence and development.
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Affiliation(s)
- Huiying Yan
- Department of Neurology, The Third Affiliated Clinical Hospital of the Changchun University of Chinese Medicine, Changchun, People's Republic of China
| | - Wei Wang
- Department of Intensive Care Unit, The Affiliated Hospital to Changchun University of Chinese Medicine, Changchun, People's Republic of China
| | - Tingting Cui
- Department of Neurology, The Third Affiliated Clinical Hospital of the Changchun University of Chinese Medicine, Changchun, People's Republic of China
| | - Yanxin Shao
- Department of Neurology, The Second Affiliated Hospital of Shandong First Medical University, Taian, People's Republic of China
| | - Mingquan Li
- Department of Neurology, The Third Affiliated Clinical Hospital of the Changchun University of Chinese Medicine, Changchun, People's Republic of China
| | - Limei Fang
- Department of Neurology, The Third Affiliated Clinical Hospital of the Changchun University of Chinese Medicine, Changchun, People's Republic of China
| | - Lina Feng
- Department of Neurology, The Third Affiliated Clinical Hospital of the Changchun University of Chinese Medicine, Changchun, People's Republic of China
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Xie PL, Zheng MY, Han R, Chen WX, Mao JH. Pharmacological mTOR inhibitors in ameliorating Alzheimer's disease: current review and perspectives. Front Pharmacol 2024; 15:1366061. [PMID: 38873415 PMCID: PMC11169825 DOI: 10.3389/fphar.2024.1366061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2024] [Accepted: 04/25/2024] [Indexed: 06/15/2024] Open
Abstract
Traditionally, pharmacological mammalian/mechanistic targets of rapamycin (mTOR) kinase inhibitors have been used during transplantation and tumor treatment. Emerging pre-clinical evidence from the last decade displayed the surprising effectiveness of mTOR inhibitors in ameliorating Alzheimer's Disease (AD), a common neurodegenerative disorder characterized by progressive cognitive function decline and memory loss. Research shows mTOR activation as an early event in AD development, and inhibiting mTOR may promote the resolution of many hallmarks of Alzheimer's. Aberrant protein aggregation, including amyloid-beta (Aβ) deposition and tau filaments, and cognitive defects, are reversed upon mTOR inhibition. A closer inspection of the evidence highlighted a temporal dependence and a hallmark-specific nature of such beneficial effects. Time of administration relative to disease progression, and a maintenance of a functional lysosomal system, could modulate its effectiveness. Moreover, mTOR inhibition also exerts distinct effects between neurons, glial cells, and endothelial cells. Different pharmacological properties of the inhibitors also produce different effects based on different blood-brain barrier (BBB) entry capacities and mTOR inhibition sites. This questions the effectiveness of mTOR inhibition as a viable AD intervention strategy. In this review, we first summarize the different mTOR inhibitors available and their characteristics. We then comprehensively update and discuss the pre-clinical results of mTOR inhibition to resolve many of the hallmarks of AD. Key pathologies discussed include Aβ deposition, tauopathies, aberrant neuroinflammation, and neurovascular system breakdowns.
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Affiliation(s)
- Pei-Lun Xie
- University College London, London, United Kingdom
| | | | - Ran Han
- Dongfang Hospital of Beijing University of Chinese Medicine, Beijing, China
| | - Wei-Xin Chen
- Dongfang Hospital of Beijing University of Chinese Medicine, Beijing, China
| | - Jin-Hua Mao
- Beijing University of Chinese Medicine, Beijing, China
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Shi Q, Gutierrez RA, Bhat MA. Microglia, Trem2, and Neurodegeneration. Neuroscientist 2024:10738584241254118. [PMID: 38769824 DOI: 10.1177/10738584241254118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
Microglia are a specialized type of neuroimmune cells that undergo morphological and molecular changes through multiple signaling pathways in response to pathological protein aggregates, neuronal death, tissue injury, or infections. Microglia express Trem2, which serves as a receptor for a multitude of ligands enhancing their phagocytic activity. Trem2 has emerged as a critical modulator of microglial activity, especially in many neurodegenerative disorders. Human TREM2 mutations are associated with an increased risk of developing Alzheimer disease (AD) and other neurodegenerative diseases. Trem2 plays dual roles in neuroinflammation and more specifically in disease-associated microglia. Most recent developments on the molecular mechanisms of Trem2, emphasizing its role in uptake and clearance of amyloid β (Aβ) aggregates and other tissue debris to help protect and preserve the brain, are encouraging. Although Trem2 normally stimulates defense mechanisms, its dysregulation can intensify inflammation, which poses major therapeutic challenges. Recent therapeutic approaches targeting Trem2 via agonistic antibodies and gene therapy methodologies present possible avenues for reducing the burden of neurodegenerative diseases. This review highlights the promise of Trem2 as a therapeutic target, especially for Aβ-associated AD, and calls for more mechanistic investigations to understand the context-specific role of microglial Trem2 in developing effective therapies against neurodegenerative diseases.
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Affiliation(s)
- Qian Shi
- Department of Cellular and Integrative Physiology, Center for Biomedical Neuroscience, Joe R. and Teresa Lozano Long School of Medicine, University of Texas Health Science Center San Antonio, San Antonio, TX, USA
| | - Raul A Gutierrez
- Department of Cellular and Integrative Physiology, Center for Biomedical Neuroscience, Joe R. and Teresa Lozano Long School of Medicine, University of Texas Health Science Center San Antonio, San Antonio, TX, USA
| | - Manzoor A Bhat
- Department of Cellular and Integrative Physiology, Center for Biomedical Neuroscience, Joe R. and Teresa Lozano Long School of Medicine, University of Texas Health Science Center San Antonio, San Antonio, TX, USA
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Davoody S, Asgari Taei A, Khodabakhsh P, Dargahi L. mTOR signaling and Alzheimer's disease: What we know and where we are? CNS Neurosci Ther 2024; 30:e14463. [PMID: 37721413 PMCID: PMC11017461 DOI: 10.1111/cns.14463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 08/28/2023] [Accepted: 08/29/2023] [Indexed: 09/19/2023] Open
Abstract
Despite the great body of research done on Alzheimer's disease, the underlying mechanisms have not been vividly investigated. To date, the accumulation of amyloid-beta plaques and tau tangles constitutes the hallmark of the disease; however, dysregulation of the mammalian target of rapamycin (mTOR) seems to be significantly involved in the pathogenesis of the disease as well. mTOR, as a serine-threonine protein kinase, was previously known for controlling many cellular functions such as cell size, autophagy, and metabolism. In this regard, mammalian target of rapamycin complex 1 (mTORC1) may leave anti-aging impacts by robustly inhibiting autophagy, a mechanism that inhibits the accumulation of damaged protein aggregate and dysfunctional organelles. Formation and aggregation of neurofibrillary tangles and amyloid-beta plaques seem to be significantly regulated by mTOR signaling. Understanding the underlying mechanisms and connection between mTOR signaling and AD may suggest conducting clinical trials assessing the efficacy of rapamycin, as an mTOR inhibitor drug, in managing AD or may help develop other medications. In this literature review, we aim to elaborate mTOR signaling network mainly in the brain, point to gaps of knowledge, and define how and in which ways mTOR signaling can be connected with AD pathogenesis and symptoms.
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Affiliation(s)
- Samin Davoody
- Student Research Committee, School of MedicineShahid Beheshti University of Medical SciencesTehranIran
| | - Afsaneh Asgari Taei
- Neuroscience Research CenterShahid Beheshti University of Medical SciencesTehranIran
| | - Pariya Khodabakhsh
- Department of NeurophysiologyInstitute of Physiology, Eberhard Karls University of TübingenTübingenGermany
| | - Leila Dargahi
- Neurobiology Research CenterShahid Beheshti University of Medical SciencesTehranIran
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Xu Z, Hu J, Wei Z, Lei Y, Afewerky HK, Gao Y, Wan L, Li L, Lei L, Liu Y, Huang F, Yu T, Wang J, Li H, Liu R, Wang X. Dynamic changes in lysosome-related pathways in APP/PS1 mice with aging. MedComm (Beijing) 2024; 5:e540. [PMID: 38606360 PMCID: PMC11006716 DOI: 10.1002/mco2.540] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 03/15/2024] [Accepted: 03/16/2024] [Indexed: 04/13/2024] Open
Abstract
Senile plaque, composed of amyloid β protein (Aβ) aggregates, is a critical pathological feature in Alzheimer's disease (AD), leading to cognitive dysfunction. However, how Aβ aggregates exert age-dependent toxicity and temporal cognitive dysfunction in APP/PS1 mice remains incompletely understood. In this study, we investigated AD pathogenesis and dynamic alterations in lysosomal pathways within the hippocampus of age-gradient male mice using transcriptome sequencing, molecular biology assays, and histopathological analyses. We observed high levels of β-amyloid precursor protein (APP) protein expression in the hippocampus at an early stage and age-dependent Aβ deposition. Transcriptome sequencing revealed the enrichment of differential genes related to the lysosome pathway. Furthermore, the protein expression of ATP6V0d2 and CTSD associated with lysosomal functions exhibited dynamic changes with age, increasing in the early stage and decreasing later. Similar age-dependent patterns were observed for the endosome function, autophagy pathway, and SGK1/FOXO3a pathway. Nissl and Golgi staining in the hippocampal region showed age-dependent neuronal loss and synaptic damage, respectively. These findings clearly define the age-gradient changes in the autophagy-lysosome system, the endosome/lysosome system, and the SGK1/FOXO3a pathway in the hippocampus of APP/PS1 mice, providing new perspectives and clues for understanding the possible mechanisms of AD, especially the transition from compensatory to decompensated state.
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Affiliation(s)
- Zhendong Xu
- Department of PathophysiologySchool of Basic MedicineKey Laboratory of Education Ministry/Hubei Province of China for Neurological DisordersTongji Medical College, Huazhong University of Science and TechnologyWuhanChina
| | - Jichang Hu
- Department of PathophysiologySchool of Basic MedicineKey Laboratory of Education Ministry/Hubei Province of China for Neurological DisordersTongji Medical College, Huazhong University of Science and TechnologyWuhanChina
| | - Zhen Wei
- Department of PathophysiologySchool of Basic MedicineKey Laboratory of Education Ministry/Hubei Province of China for Neurological DisordersTongji Medical College, Huazhong University of Science and TechnologyWuhanChina
| | - Yu Lei
- Department of PathophysiologySchool of Basic MedicineKey Laboratory of Education Ministry/Hubei Province of China for Neurological DisordersTongji Medical College, Huazhong University of Science and TechnologyWuhanChina
| | - Henok Kessete Afewerky
- Department of PathophysiologySchool of Basic MedicineKey Laboratory of Education Ministry/Hubei Province of China for Neurological DisordersTongji Medical College, Huazhong University of Science and TechnologyWuhanChina
| | - Yang Gao
- Department of PathophysiologySchool of Basic MedicineKey Laboratory of Education Ministry/Hubei Province of China for Neurological DisordersTongji Medical College, Huazhong University of Science and TechnologyWuhanChina
| | - Lu Wan
- Department of PathophysiologySchool of Basic MedicineKey Laboratory of Education Ministry/Hubei Province of China for Neurological DisordersTongji Medical College, Huazhong University of Science and TechnologyWuhanChina
| | - Longfei Li
- Department of PathophysiologySchool of Basic MedicineKey Laboratory of Education Ministry/Hubei Province of China for Neurological DisordersTongji Medical College, Huazhong University of Science and TechnologyWuhanChina
| | - Ling Lei
- Department of PathophysiologySchool of Basic MedicineKey Laboratory of Education Ministry/Hubei Province of China for Neurological DisordersTongji Medical College, Huazhong University of Science and TechnologyWuhanChina
| | - Yi Liu
- Department of PathophysiologySchool of Basic MedicineKey Laboratory of Education Ministry/Hubei Province of China for Neurological DisordersTongji Medical College, Huazhong University of Science and TechnologyWuhanChina
| | - Fang Huang
- Department of PathophysiologySchool of Basic MedicineKey Laboratory of Education Ministry/Hubei Province of China for Neurological DisordersTongji Medical College, Huazhong University of Science and TechnologyWuhanChina
| | - Tong Yu
- Department of PathophysiologySchool of Basic MedicineKey Laboratory of Education Ministry/Hubei Province of China for Neurological DisordersTongji Medical College, Huazhong University of Science and TechnologyWuhanChina
| | - Jian‐Zhi Wang
- Department of PathophysiologySchool of Basic MedicineKey Laboratory of Education Ministry/Hubei Province of China for Neurological DisordersTongji Medical College, Huazhong University of Science and TechnologyWuhanChina
- Co‐innovation Center of NeuroregenerationNantong UniversityNantongChina
| | - Hong‐Lian Li
- Department of PathophysiologySchool of Basic MedicineKey Laboratory of Education Ministry/Hubei Province of China for Neurological DisordersTongji Medical College, Huazhong University of Science and TechnologyWuhanChina
| | - Rong Liu
- Department of PathophysiologySchool of Basic MedicineKey Laboratory of Education Ministry/Hubei Province of China for Neurological DisordersTongji Medical College, Huazhong University of Science and TechnologyWuhanChina
| | - Xiaochuan Wang
- Department of PathophysiologySchool of Basic MedicineKey Laboratory of Education Ministry/Hubei Province of China for Neurological DisordersTongji Medical College, Huazhong University of Science and TechnologyWuhanChina
- Co‐innovation Center of NeuroregenerationNantong UniversityNantongChina
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García-Juan M, Ordóñez-Gutiérrez L, Wandosell F. Clearance of β-amyloid mediated by autophagy is enhanced by MTORC1 inhibition but not AMPK activation in APP/PSEN1 astrocytes. Glia 2024; 72:588-606. [PMID: 38009275 DOI: 10.1002/glia.24492] [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: 02/08/2023] [Revised: 11/07/2023] [Accepted: 11/13/2023] [Indexed: 11/28/2023]
Abstract
Proteostasis mechanisms mediated by macroautophagy/autophagy are altered in neurodegenerative diseases such as Alzheimer disease (AD) and their recovery/enhancement has been proposed as a therapeutic approach. From the two central nodes in the anabolism-catabolism balance, it is generally accepted that mechanistic target of rapamycin kinase complex 1 (MTORC1)_ activation leads to the inhibition of autophagy, whereas adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) has the opposite role. In AD, amyloid beta (Aβ) production disturbs the optimal neuronal/glial proteostasis. As astrocytes are essential for brain homeostasis, the purpose of this work was to analyze if the upregulation of autophagy in this cell type, either by MTORC1 inhibition or AMPK activation, could modulate the generation/degradation of β-amyloid. By using primary astrocytes from amyloid beta precursor protein (APP)/Presenilin 1 (PSEN1) mouse model of AD, we confirmed that MTORC1 inhibition reduced Aβ secretion through moderate autophagy induction. Surprisingly, pharmacologically increased activity of AMPK did not enhance autophagy but had different effects on Aβ secretion. Conversely, AMPK inhibition did not affect autophagy but reduced Aβ secretion. These puzzling data were confirmed through the overexpression of different mutant AMPK isoforms: while only the constitutively active AMPK increased autophagy, all versions augmented Aβ secretion. We conclude that AMPK has a significantly different role in primary astrocytes than in other reported cells, similar to our previous findings in neurons. Our data support that perhaps only a basal AMPK activity is needed to maintain autophagy whereas the increased activity, either physiologically or pharmacologically, has no direct effect on autophagy-dependent amyloidosis. These results shed light on the controversy about the therapeutic effect of AMPK activation on autophagy induction.
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Affiliation(s)
- Marta García-Juan
- Centro de Biología Molecular "Severo Ochoa" (CSIC-UAM), Nicolas Cabrera 1, Universidad Autónoma de Madrid, Madrid, Spain
| | - Lara Ordóñez-Gutiérrez
- Centro de Biología Molecular "Severo Ochoa" (CSIC-UAM), Nicolas Cabrera 1, Universidad Autónoma de Madrid, Madrid, Spain
- Departamento de Bioquímica ry Biología Molecular, Universidad Complutense de Madrid, Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Francisco Wandosell
- Centro de Biología Molecular "Severo Ochoa" (CSIC-UAM), Nicolas Cabrera 1, Universidad Autónoma de Madrid, Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
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10
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Lopez JJD, Gaza JT, Nellas RB. The role of glycerol-water mixtures in the stability of FKBP12-rapalog-FRB complexes. J Mol Graph Model 2023; 124:108556. [PMID: 37423019 DOI: 10.1016/j.jmgm.2023.108556] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2022] [Revised: 04/27/2023] [Accepted: 06/16/2023] [Indexed: 07/11/2023]
Abstract
The thermodynamic and biophysical implications of the introduction of a co-solvent during protein-ligand binding remain elusive. Using ternary complexes of 12-kDa FK506 binding protein (FKBP12), FKBP-rapamycin binding (FRB) domain of the mammalian/mechanistic target of rapamycin (mTOR) kinase, and rapamycin analogs (rapalogs) in glycerol-water mixtures, the influence of solvent composition on ligand binding dynamics was explored. The pharmaceutical potential of rapalogs and the utility of glycerol as a co-solvent in drug delivery applications were critical in deciding the system to be studied. Consolidation of existing studies on rapamycin modification was first performed to strategically design a new rapalog called T1. The results from 100-ns dual-boost Gaussian accelerated molecular dynamics simulations showed that protein stability was induced in the presence of glycerol. Reweighting of the trajectories revealed that the glycerol-rich solvent system lowers the energy barrier in the conformational space of the protein while also preserving native contacts between the ligand and the residues in the binding site. Calculated binding free energies using MM/GBSA also showed that electrostatic energy and polar contribution of solvation energy are heavily influenced by the changes in solvation. Glycerol molecules are preferentially excluded through electrostatic interactions from the solvation shell which induce complex stability as seen in existing experiments. Hence, using glycerol as a co-solvent in rapamycin delivery has a significant role in maintaining stability. In addition, compound T1 is a potential mTORC1-selective inhibitor with strong affinity for the FKBP12-FRB complex. This study aims to provide insights on the design of new rapalogs, and the applicability of glycerol as co-solvent for FKBP12-rapalog-FRB complexes.
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Affiliation(s)
- Joshua Jener D Lopez
- Institute of Chemistry, College of Science, University of the Philippines Diliman, Quezon City, 1101, Philippines
| | - Jokent T Gaza
- Institute of Chemistry, College of Science, University of the Philippines Diliman, Quezon City, 1101, Philippines
| | - Ricky B Nellas
- Institute of Chemistry, College of Science, University of the Philippines Diliman, Quezon City, 1101, Philippines.
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11
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Kocherlakota S, Das Y, Swinkels D, Vanmunster M, Callens M, Vinckier S, Vaz FM, Sinha D, Van Veldhoven PP, Fransen M, Baes M. The murine retinal pigment epithelium requires peroxisomal β-oxidation to maintain lysosomal function and prevent dedifferentiation. Proc Natl Acad Sci U S A 2023; 120:e2301733120. [PMID: 37862382 PMCID: PMC10614831 DOI: 10.1073/pnas.2301733120] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Accepted: 08/14/2023] [Indexed: 10/22/2023] Open
Abstract
Retinal pigment epithelium (RPE) cells have to phagocytose shed photoreceptor outer segments (POS) on a daily basis over the lifetime of an organism, but the mechanisms involved in the digestion and recycling of POS lipids are poorly understood. Although it was frequently assumed that peroxisomes may play an essential role, this was never investigated. Here, we show that global as well as RPE-selective loss of peroxisomal β-oxidation in multifunctional protein 2 (MFP2) knockout mice impairs the digestive function of lysosomes in the RPE at a very early age, followed by RPE degeneration. This was accompanied by prolonged mammalian target of rapamycin activation, lipid deregulation, and mitochondrial structural anomalies without, however, causing oxidative stress or energy shortage. The RPE degeneration caused secondary photoreceptor death. Notably, the deterioration of the RPE did not occur in an Mfp2/rd1 mutant mouse line, characterized by absent POS shedding. Our findings prove that peroxisomal β-oxidation in the RPE is essential for handling the polyunsaturated fatty acids present in ingested POS and shed light on retinopathy in patients with peroxisomal disorders. Our data also have implications for gene therapy development as they highlight the importance of targeting the RPE in addition to the photoreceptor cells.
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Affiliation(s)
- Sai Kocherlakota
- Laboratory of Cell Metabolism, Department of Pharmaceutical and Pharmacological Sciences, Katholieke Universiteit Leuven, Leuven3000, Belgium
| | - Yannick Das
- Laboratory of Cell Metabolism, Department of Pharmaceutical and Pharmacological Sciences, Katholieke Universiteit Leuven, Leuven3000, Belgium
| | - Daniëlle Swinkels
- Laboratory of Cell Metabolism, Department of Pharmaceutical and Pharmacological Sciences, Katholieke Universiteit Leuven, Leuven3000, Belgium
| | - Maarten Vanmunster
- Laboratory of Cell Metabolism, Department of Pharmaceutical and Pharmacological Sciences, Katholieke Universiteit Leuven, Leuven3000, Belgium
| | - Manon Callens
- Laboratory of Cell Metabolism, Department of Pharmaceutical and Pharmacological Sciences, Katholieke Universiteit Leuven, Leuven3000, Belgium
| | - Stefan Vinckier
- Laboratory of Angiogenesis and Vascular Metabolism, Center for Cancer Biology, Vlaams Insituut voor Biotechnologie, Leuven3000, Belgium
- Department of Oncology, Leuven Cancer Institute, Katholieke Universiteit Leuven, Leuven3000, Belgium
| | - Frédéric M. Vaz
- Laboratory Genetic Metabolic Diseases, Department of Clinical Chemistry, Amsterdam Gastroenterology and Metabolism, Amsterdam University Medical Center, University of Amsterdam, Amsterdam1105AZ, The Netherlands
- Core Facility Metabolomics, Amsterdam University Medical Center, Amsterdam1105AZ, The Netherlands
| | - Debasish Sinha
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA15213
- Wilmer Eye Institute, The Johns Hopkins University School of Medicine, Baltimore, MD21287
| | - Paul P. Van Veldhoven
- Laboratory of Peroxisome Biology and Intracellular Communication, Department of Cellular and Molecular Medicine, Katholieke Universiteit Leuven, Leuven3000, Belgium
| | - Marc Fransen
- Laboratory of Peroxisome Biology and Intracellular Communication, Department of Cellular and Molecular Medicine, Katholieke Universiteit Leuven, Leuven3000, Belgium
| | - Myriam Baes
- Laboratory of Cell Metabolism, Department of Pharmaceutical and Pharmacological Sciences, Katholieke Universiteit Leuven, Leuven3000, Belgium
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12
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Hou SJ, Zhang SX, Li Y, Xu SY. Rapamycin Responds to Alzheimer's Disease: A Potential Translational Therapy. Clin Interv Aging 2023; 18:1629-1639. [PMID: 37810956 PMCID: PMC10557994 DOI: 10.2147/cia.s429440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Accepted: 09/25/2023] [Indexed: 10/10/2023] Open
Abstract
Alzheimer's disease (AD) is a sporadic or familial neurodegenerative disease of insidious onset with progressive cognitive decline. Although numerous studies have been conducted or are underway on AD, there are still no effective drugs to reverse the pathological features and clinical manifestations of AD. Rapamycin is a macrolide antibiotic produced by Streptomyces hygroscopicus. As a classical mechanistic target of rapamycin (mTOR) inhibitor, rapamycin has been shown to be beneficial in a variety of AD mouse and cells models, both before the onset of disease symptoms and the early stage of disease. Although many basic studies have demonstrated the therapeutic effects of rapamycin in AD, many questions and controversies remain. This may be due to the variability of experimental models, different modes of administration, dose, timing, frequency, and the availability of drug-targeting vehicles. Rapamycin may delay the development of AD by reducing β-amyloid (Aβ) deposition, inhibiting tau protein hyperphosphorylation, maintaining brain function in APOE ε4 gene carriers, clearing chronic inflammation, and improving cognitive dysfunction. It is thus expected to be one of the candidates for the treatment of Alzheimer's disease.
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Affiliation(s)
- Si-Jia Hou
- Department of Neurology, Headache Center, The First Hospital of Shanxi Medical University, Taiyuan, Shanxi Province, 030001, People’s Republic of China
| | - Sheng-Xiao Zhang
- Department of Rheumatology, The Second Hospital of Shanxi Medical University, Taiyuan, Shanxi Province, 030009, People’s Republic of China
| | - Yang Li
- Department of Neurology, Headache Center, The First Hospital of Shanxi Medical University, Taiyuan, Shanxi Province, 030001, People’s Republic of China
| | - Sui-Yi Xu
- Department of Neurology, Headache Center, The First Hospital of Shanxi Medical University, Taiyuan, Shanxi Province, 030001, People’s Republic of China
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13
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Moon HR, Yun JM. Neuroprotective effects of hesperetin on H 2O 2-induced damage in neuroblastoma SH-SY5Y cells. Nutr Res Pract 2023; 17:899-916. [PMID: 37780221 PMCID: PMC10522820 DOI: 10.4162/nrp.2023.17.5.899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 06/12/2023] [Accepted: 07/06/2023] [Indexed: 10/03/2023] Open
Abstract
BACKGROUND/OBJECTIVES Oxidative stress is a fundamental neurodegenerative disease trigger that damages and decimates nerve cells. Neurodegenerative diseases are chronic central nervous system disorders that progress and result from neuronal degradation and loss. Recent studies have extensively focused on neurodegenerative disease treatment and prevention using dietary compounds. Heseperetin is an aglycone hesperidin form with various physiological activities, such as anti-inflammation, antioxidant, and antitumor. However, few studies have considered hesperetin's neuroprotective effects and mechanisms; thus, our study investigated this in hydrogen peroxide (H2O2)-treated SH-SY5Y cells. MATERIALS/METHODS SH-SY5Y cells were treated with H2O2 (400 µM) in hesperetin absence or presence (10-40 µM) for 24 h. Three-(4,5-Dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assays detected cell viability, and 4',6-diamidino-2-phenylindole staining allowed us to observe nuclear morphology changes such as chromatin condensation and apoptotic nuclei. Reactive oxygen species (ROS) detection assays measured intracellular ROS production; Griess reaction assays assessed nitric oxide (NO) production. Western blotting and quantitative polymerase chain reactions quantified corresponding mRNA and proteins. RESULTS Subsequent experiments utilized various non-toxic hesperetin concentrations, establishing that hesperetin notably decreased intracellular ROS and NO production in H2O2-treated SH-SY5Y cells (P < 0.05). Furthermore, hesperetin inhibited H2O2-induced inflammation-related gene expression, including interluekin-6, tumor necrosis factor-α, and nuclear factor kappa B (NF-κB) p65 activation. In addition, hesperetin inhibited NF-κB translocation into H2O2-treated SH-SY5Y cell nuclei and suppressed mitogen-activated protein kinase protein expression, an essential apoptotic cell death regulator. Various apoptosis hallmarks, including shrinkage and nuclear condensation in H2O2-treated cells, were suppressed dose-dependently. Additionally, hesperetin treatment down-regulated Bax/Bcl-2 expression ratios and activated AMP-activated protein kinase-mammalian target of rapamycin autophagy pathways. CONCLUSION These results substantiate that hesperetin activates autophagy and inhibits apoptosis and inflammation. Hesperetin is a potentially potent dietary agent that reduces neurodegenerative disease onset, progression, and prevention.
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Affiliation(s)
- Ha-Rin Moon
- Department of Food and Nutrition, Chonnam National University, Gwangju 61186, Korea
| | - Jung-Mi Yun
- Department of Food and Nutrition, Chonnam National University, Gwangju 61186, Korea
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14
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Sousa T, Moreira PI, Cardoso S. Current Advances in Mitochondrial Targeted Interventions in Alzheimer's Disease. Biomedicines 2023; 11:2331. [PMID: 37760774 PMCID: PMC10525414 DOI: 10.3390/biomedicines11092331] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 08/16/2023] [Accepted: 08/18/2023] [Indexed: 09/29/2023] Open
Abstract
Alzheimer's disease is the most prevalent neurodegenerative disorder and affects the lives not only of those who are diagnosed but also of their caregivers. Despite the enormous social, economic and political burden, AD remains a disease without an effective treatment and with several failed attempts to modify the disease course. The fact that AD clinical diagnosis is most often performed at a stage at which the underlying pathological events are in an advanced and conceivably irremediable state strongly hampers treatment attempts. This raises the awareness of the need to identify and characterize the early brain changes in AD, in order to identify possible novel therapeutic targets to circumvent AD's cascade of events. One of the most auspicious targets is mitochondria, powerful organelles found in nearly all cells of the body. A vast body of literature has shown that mitochondria from AD patients and model organisms of the disease differ from their non-AD counterparts. In view of this evidence, preserving and/or restoring mitochondria's health and function can represent the primary means to achieve advances to tackle AD. In this review, we will briefly assess and summarize the previous and latest evidence of mitochondria dysfunction in AD. A particular focus will be given to the recent updates and advances in the strategy options aimed to target faulty mitochondria in AD.
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Affiliation(s)
- Tiago Sousa
- Faculty of Medicine, University of Coimbra, 3000-370 Coimbra, Portugal;
| | - Paula I. Moreira
- CNC—Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal;
- CIBB—Center for Innovative Biomedicine and Biotechnology, University of Coimbra, 3004-504 Coimbra, Portugal
- Institute of Physiology, Faculty of Medicine, University of Coimbra, 3000-370 Coimbra, Portugal
| | - Susana Cardoso
- CNC—Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal;
- CIBB—Center for Innovative Biomedicine and Biotechnology, University of Coimbra, 3004-504 Coimbra, Portugal
- IIIUC—Institute for Interdisciplinary Research, University of Coimbra, 3030-789 Coimbra, Portugal
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15
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Carosi JM, Sargeant TJ. Rapamycin and Alzheimer disease: a hypothesis for the effective use of rapamycin for treatment of neurodegenerative disease. Autophagy 2023; 19:2386-2390. [PMID: 36727410 PMCID: PMC10351443 DOI: 10.1080/15548627.2023.2175569] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 01/26/2023] [Accepted: 01/30/2023] [Indexed: 02/03/2023] Open
Abstract
In 2019 we summarized work relating to the potential use of rapamycin for treating Alzheimer disease (AD). We considered the commentary necessary because use of rapamycin in people with AD is a very real prospect and we wanted to present a balanced view of the likely consequences of MTOR (mechanistic target of rapamycin kinase) inhibition in the AD brain. We concluded that use of rapamycin, an MTOR inhibitor that increases macroautophagy/autophagy, could hold promise for prevention of AD if used early enough. However, MTOR inhibition appeared ineffectual in resolving existing amyloid pathology in AD mouse models. In this View article, we update these observations with new studies that have used rapamycin in AD models and provide evidence both for and against its use in AD. We also discuss rapamycin in the light of new research that describes rapamycin-induced autophagic stress in the aging brain and autophagic stress as the origin of the amyloid plaque itself. We conclude that rapamycin will have complex effects on the brain in AD. Further, we hypothesize that lysosomal degradative capacity in the brain will likely determine how effective or detrimental rapamycin will be as a treatment of AD.Abbreviations: AD: Alzheimer disease; APP: amyloid beta precursor protein; MAPT/tau: microtubule associated protein tau; MTOR: mechanistic target of rapamycin kinase; MTORC1: mechanistic target of rapamycin kinase complex 1.
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Affiliation(s)
- Julian M Carosi
- Lysosomal Health in Ageing, Hopwood Centre for Neurobiology, Lifelong Health Theme, South Australian Health and Medical Research Institute (SAHMRI), Adelaide, Australia
| | - Timothy J Sargeant
- Lysosomal Health in Ageing, Hopwood Centre for Neurobiology, Lifelong Health Theme, South Australian Health and Medical Research Institute (SAHMRI), Adelaide, Australia
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16
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Zhang C, Chen H, Rodriguez Y, Ma X, Swerdlow RH, Zhang J, Ding WX. A perspective on autophagy and transcription factor EB in Alcohol-Associated Alzheimer's disease. Biochem Pharmacol 2023; 213:115576. [PMID: 37127251 PMCID: PMC11009931 DOI: 10.1016/j.bcp.2023.115576] [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: 03/03/2023] [Revised: 04/21/2023] [Accepted: 04/24/2023] [Indexed: 05/03/2023]
Abstract
Alzheimer's disease (AD) is the most common form of progressive dementia and there is no truly efficacious treatment. Accumulating evidence indicates that impaired autophagic function for removal of damaged mitochondria and protein aggregates such as amyloid and tau protein aggregates may contribute to the pathogenesis of AD. Epidemiologic studies have implicated alcohol abuse in promoting AD, yet the underlying mechanisms are poorly understood. In this review, we discuss mechanisms of selective autophagy for mitochondria and protein aggregates and how these mechanisms are impaired by aging and alcohol consumption. We also discuss potential genetic and pharmacological approaches for targeting autophagy/mitophagy, as well as lysosomal and mitochondrial biogenesis, for the potential prevention and treatment of AD.
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Affiliation(s)
- Chen Zhang
- Department of Pharmacology, Toxicology and Therapeutics, The University of Kansas Medical Center, Kansas City, KS 66160, USA
| | - Hao Chen
- Department of Pharmacology, Toxicology and Therapeutics, The University of Kansas Medical Center, Kansas City, KS 66160, USA
| | - Yssa Rodriguez
- Department of Pharmacology, Toxicology and Therapeutics, The University of Kansas Medical Center, Kansas City, KS 66160, USA
| | - Xiaowen Ma
- Department of Pharmacology, Toxicology and Therapeutics, The University of Kansas Medical Center, Kansas City, KS 66160, USA
| | - Russell H Swerdlow
- Department of Neurology, The University of Kansas Medical Center, Kansas City, KS 66160, USA
| | - Jianhua Zhang
- Department of Pathology, Division of Molecular Cellular Pathology, University of Alabama at Birmingham, 901 19th street South, Birmingham, AL 35294, USA
| | - Wen-Xing Ding
- Department of Pharmacology, Toxicology and Therapeutics, The University of Kansas Medical Center, Kansas City, KS 66160, USA; Department of Internal Medicine, Division of Gastroenterology, Hepatology & Motility, The University of Kansas Medical Center, Kansas City, KS 66160, USA.
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17
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Ranglani S, Ashton A, Mahfooz K, Komorowska J, Graur A, Kabbani N, Garcia-Rates S, Greenfield S. A Novel Bioactive Peptide, T14, Selectively Activates mTORC1 Signalling: Therapeutic Implications for Neurodegeneration and Other Rapamycin-Sensitive Applications. Int J Mol Sci 2023; 24:9961. [PMID: 37373106 DOI: 10.3390/ijms24129961] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Revised: 06/06/2023] [Accepted: 06/07/2023] [Indexed: 06/29/2023] Open
Abstract
T14 modulates calcium influx via the α-7 nicotinic acetylcholine receptor to regulate cell growth. Inappropriate triggering of this process has been implicated in Alzheimer's disease (AD) and cancer, whereas T14 blockade has proven therapeutic potential in in vitro, ex vivo and in vivo models of these pathologies. Mammalian target of rapamycin complex 1 (mTORC1) is critical for growth, however its hyperactivation is implicated in AD and cancer. T14 is a product of the longer 30mer-T30. Recent work shows that T30 drives neurite growth in the human SH-SY5Y cell line via the mTOR pathway. Here, we demonstrate that T30 induces an increase in mTORC1 in PC12 cells, and ex vivo rat brain slices containing substantia nigra, but not mTORC2. The increase in mTORC1 by T30 in PC12 cells is attenuated by its blocker, NBP14. Moreover, in post-mortem human midbrain, T14 levels correlate significantly with mTORC1. Silencing mTORC1 reverses the effects of T30 on PC12 cells measured via AChE release in undifferentiated PC12 cells, whilst silencing mTORC2 does not. This suggests that T14 acts selectively via mTORC1. T14 blockade offers a preferable alternative to currently available blockers of mTOR as it would enable selective blockade of mTORC1, thereby reducing side effects associated with generalised mTOR blockade.
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Affiliation(s)
- Sanskar Ranglani
- Neuro Bio Ltd., Building F5, Culham Science Centre, Abingdon OX14 3DB, UK
| | - Anna Ashton
- Neuro Bio Ltd., Building F5, Culham Science Centre, Abingdon OX14 3DB, UK
| | - Kashif Mahfooz
- Neuro Bio Ltd., Building F5, Culham Science Centre, Abingdon OX14 3DB, UK
| | - Joanna Komorowska
- Neuro Bio Ltd., Building F5, Culham Science Centre, Abingdon OX14 3DB, UK
| | - Alexandru Graur
- School of Systems Biology, George Mason University, Fairfax, VA 22030, USA
| | - Nadine Kabbani
- School of Systems Biology, George Mason University, Fairfax, VA 22030, USA
| | - Sara Garcia-Rates
- Neuro Bio Ltd., Building F5, Culham Science Centre, Abingdon OX14 3DB, UK
| | - Susan Greenfield
- Neuro Bio Ltd., Building F5, Culham Science Centre, Abingdon OX14 3DB, UK
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18
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Mayor E. Neurotrophic effects of intermittent fasting, calorie restriction and exercise: a review and annotated bibliography. FRONTIERS IN AGING 2023; 4:1161814. [PMID: 37334045 PMCID: PMC10273285 DOI: 10.3389/fragi.2023.1161814] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Accepted: 05/09/2023] [Indexed: 06/20/2023]
Abstract
In the last decades, important progress has been achieved in the understanding of the neurotrophic effects of intermittent fasting (IF), calorie restriction (CR) and exercise. Improved neuroprotection, synaptic plasticity and adult neurogenesis (NSPAN) are essential examples of these neurotrophic effects. The importance in this respect of the metabolic switch from glucose to ketone bodies as cellular fuel has been highlighted. More recently, calorie restriction mimetics (CRMs; resveratrol and other polyphenols in particular) have been investigated thoroughly in relation to NSPAN. In the narrative review sections of this manuscript, recent findings on these essential functions are synthesized and the most important molecules involved are presented. The most researched signaling pathways (PI3K, Akt, mTOR, AMPK, GSK3β, ULK, MAPK, PGC-1α, NF-κB, sirtuins, Notch, Sonic hedgehog and Wnt) and processes (e.g., anti-inflammation, autophagy, apoptosis) that support or thwart neuroprotection, synaptic plasticity and neurogenesis are then briefly presented. This provides an accessible entry point to the literature. In the annotated bibliography section of this contribution, brief summaries are provided of about 30 literature reviews relating to the neurotrophic effects of interest in relation to IF, CR, CRMs and exercise. Most of the selected reviews address these essential functions from the perspective of healthier aging (sometimes discussing epigenetic factors) and the reduction of the risk for neurodegenerative diseases (Alzheimer's disease, Huntington's disease, Parkinson's disease) and depression or the improvement of cognitive function.
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19
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Mitra R, Premraj L, Khoo TK. Neuromelanin: Its role in the pathogenesis of idiopathic Parkinson's disease and potential as a therapeutic target. Parkinsonism Relat Disord 2023:105448. [PMID: 37236833 DOI: 10.1016/j.parkreldis.2023.105448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2023] [Revised: 05/10/2023] [Accepted: 05/18/2023] [Indexed: 05/28/2023]
Abstract
Parkinson's disease is an increasingly prevalent condition that involves the marked loss of dopaminergic neurons in the substantia nigra pars compacta. These neurons pigmented with neuromelanin along with other regions of the brain are almost exclusively victims of neurodegeneration in the disease. The link between neuromelanin and Parkinson's disease has been widely studied for decades. While many studies have outlined the pigment's neuroprotective function as a potent free radical scavenger, antioxidant, and ion-chelator, it has also been observed to play a role in cell death due to mitochondrial dysfunction and oxidative stress, especially in the parkinsonian disease state. This is due to the damaging effects of neuromelanin precursors, neuromelanin-related ion dysregulation and intra- and extraneuronal neuromelanin accumulation. Current and emerging therapeutic endeavours guided by these pathological processes may include antioxidant therapy, proteostasis enhancement, ion chelation and neuromelanin-targeted immunotherapy to prevent the accumulation, formation and effects of neuromelanin and oxidative neuromelanin precursors. Some of these therapeutic strategies are already in nascent stages, while others have produced mixed results in clinical trials. This review aims to provide an update on how neuromelanin and neuromelanin-related substances may be linked to the pathogenesis of Parkinson's disease and how future therapeutic strategies may be able to hamper or prevent neuromelanin-related pathological processes and ultimately modify disease progression in Parkinson's.
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Affiliation(s)
- Ritoban Mitra
- College of Medicine and Public Health, Flinders University, South Australia, Australia.
| | - Lavienraj Premraj
- School of Medicine & Dentistry, Griffith University, Queensland, Australia
| | - Tien K Khoo
- School of Medicine & Dentistry, Griffith University, Queensland, Australia; Graduate School of Medicine, University of Wollongong, New South Wales, Australia
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20
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Sonsalla MM, Lamming DW. Geroprotective interventions in the 3xTg mouse model of Alzheimer's disease. GeroScience 2023:10.1007/s11357-023-00782-w. [PMID: 37022634 PMCID: PMC10400530 DOI: 10.1007/s11357-023-00782-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Accepted: 03/23/2023] [Indexed: 04/07/2023] Open
Abstract
Alzheimer's disease (AD) is an age-associated neurodegenerative disease. As the population ages, the increasing prevalence of AD threatens massive healthcare costs in the coming decades. Unfortunately, traditional drug development efforts for AD have proven largely unsuccessful. A geroscience approach to AD suggests that since aging is the main driver of AD, targeting aging itself may be an effective way to prevent or treat AD. Here, we discuss the effectiveness of geroprotective interventions on AD pathology and cognition in the widely utilized triple-transgenic mouse model of AD (3xTg-AD) which develops both β-amyloid and tau pathologies characteristic of human AD, as well as cognitive deficits. We discuss the beneficial impacts of calorie restriction (CR), the gold standard for geroprotective interventions, and the effects of other dietary interventions including protein restriction. We also discuss the promising preclinical results of geroprotective pharmaceuticals, including rapamycin and medications for type 2 diabetes. Though these interventions and treatments have beneficial effects in the 3xTg-AD model, there is no guarantee that they will be as effective in humans, and we discuss the need to examine these interventions in additional animal models as well as the urgent need to test if some of these approaches can be translated from the lab to the bedside for the treatment of humans with AD.
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Affiliation(s)
- Michelle M Sonsalla
- Department of Medicine, University of Wisconsin-Madison, 2500 Overlook Terrace, VAH C3127 Research 151, Madison, WI, 53705, USA
- William S. Middleton Memorial Veterans Hospital, Madison, WI, 53705, USA
- Comparative Biomedical Sciences Graduate Program, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Dudley W Lamming
- Department of Medicine, University of Wisconsin-Madison, 2500 Overlook Terrace, VAH C3127 Research 151, Madison, WI, 53705, USA.
- William S. Middleton Memorial Veterans Hospital, Madison, WI, 53705, USA.
- Comparative Biomedical Sciences Graduate Program, University of Wisconsin-Madison, Madison, WI, 53706, USA.
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21
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Bensalem J, Hein LK, Hassiotis S, Trim PJ, Proud CG, Heilbronn LK, Sargeant TJ. Modifying Dietary Protein Impacts mTOR Signaling and Brain Deposition of Amyloid β in a Knock-In Mouse Model of Alzheimer Disease. J Nutr 2023; 153:1407-1419. [PMID: 36870538 DOI: 10.1016/j.tjnut.2023.02.035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 01/24/2023] [Accepted: 02/28/2023] [Indexed: 03/06/2023] Open
Abstract
BACKGROUND Alzheimer disease (AD) is a neurodegenerative condition defined by the build-up of amyloid plaques in the brain and intraneuronal tangles of the protein tau. Autophagy is a cellular cleaning process involved in the degradation of proteins, including proteins directly responsible for amyloid plaques, but its activity is compromised in AD. The mechanistic target of rapamycin complex (mTORC) 1 inhibits autophagy when activated by amino acids. OBJECTIVES We hypothesized that reducing amino acid intake by decreasing dietary protein could promote autophagy, which in turn could prevent amyloid plaque deposition in AD mice. METHODS Homozygote (2-mo-old) and heterozygote (4-mo-old) amyloid precursor protein NL-G-F mice, a model of brain amyloid deposition, were used in this study to test this hypothesis. Male and female mice were fed with isocaloric low-protein, control, or high-protein diets for 4 mo and killed for analysis. Locomotor performance was measured using the inverted screen test, and body composition was measured using EchoMRI. Samples were analyzed using western blotting, enzyme-linked immunosorbent assay, mass spectrometry, and immunohistochemical staining. RESULTS mTORC1 activity in the cerebral cortex was inversely covaried with protein consumption in both homozygote and heterozygote mice. Low-protein diet improved metabolic parameters and restored locomotor performance only in male homozygous mice. Dietary protein adjustment did not affect amyloid deposition in homozygous mice. However, in the heterozygous amyloid precursor protein NL-G-F mice, amyloid plaque was lower in male mice consuming the low protein compared with that in mice fed with the control diet. CONCLUSIONS This study showed that reducing protein intake reduces mTORC1 activity and may prevent amyloid accumulation, at least in male mice. Moreover, dietary protein is a tool that can be used to change mTORC1 activity and amyloid deposition in the mouse brain, and the murine brain's response to dietary protein is sex specific.
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Affiliation(s)
- Julien Bensalem
- Lysosomal Health in Ageing, Hopwood Centre for Neurobiology, Lifelong Health Theme, South Australian Health and Medical Research Institute (SAHMRI), Adelaide, South Australia, Australia; Adelaide Medical School, Faculty of Health and Medical Sciences, The University of Adelaide, Adelaide, South Australia, Australia
| | - Leanne K Hein
- Lysosomal Health in Ageing, Hopwood Centre for Neurobiology, Lifelong Health Theme, South Australian Health and Medical Research Institute (SAHMRI), Adelaide, South Australia, Australia
| | - Sofia Hassiotis
- Lysosomal Health in Ageing, Hopwood Centre for Neurobiology, Lifelong Health Theme, South Australian Health and Medical Research Institute (SAHMRI), Adelaide, South Australia, Australia
| | - Paul J Trim
- Proteomics, Metabolomics and MS-Imaging Core Facility, South Australian Health and Medical Research Institute (SAHMRI), Adelaide, South Australia, Australia
| | - Christopher G Proud
- Lifelong Health Theme, South Australian Health and Medical Research Institute (SAHMRI), Adelaide, South Australia, Australia
| | - Leonie K Heilbronn
- Adelaide Medical School, Faculty of Health and Medical Sciences, The University of Adelaide, Adelaide, South Australia, Australia; Nutrition, Metabolism & Gut Health, Lifelong Health Theme, South Australian Health and Medical Research Institute (SAHMRI), Adelaide, South Australia, Australia
| | - Timothy J Sargeant
- Lysosomal Health in Ageing, Hopwood Centre for Neurobiology, Lifelong Health Theme, South Australian Health and Medical Research Institute (SAHMRI), Adelaide, South Australia, Australia; Adelaide Medical School, Faculty of Health and Medical Sciences, The University of Adelaide, Adelaide, South Australia, Australia.
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22
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Amin AM, Mostafa H, Khojah HMJ. Insulin resistance in Alzheimer's disease: The genetics and metabolomics links. Clin Chim Acta 2023; 539:215-236. [PMID: 36566957 DOI: 10.1016/j.cca.2022.12.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2022] [Revised: 12/16/2022] [Accepted: 12/16/2022] [Indexed: 12/24/2022]
Abstract
Alzheimer's disease (AD) is a neurodegenerative disease with significant socioeconomic burden worldwide. Although genetics and environmental factors play a role, AD is highly associated with insulin resistance (IR) disorders such as metabolic syndrome (MS), obesity, and type two diabetes mellitus (T2DM). These findings highlight a shared pathogenesis. The use of metabolomics as a downstream systems' biology (omics) approach can help to identify these shared metabolic traits and assist in the early identification of at-risk groups and potentially guide therapy. Targeting the shared AD-IR metabolic trait with lifestyle interventions and pharmacological treatments may offer promising AD therapeutic approach. In this narrative review, we reviewed the literature on the AD-IR pathogenic link, the shared genetics and metabolomics biomarkers between AD and IR disorders, as well as the lifestyle interventions and pharmacological treatments which target this pathogenic link.
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Affiliation(s)
- Arwa M Amin
- Department of Clinical and Hospital Pharmacy, College of Pharmacy, Taibah University, Madinah, Saudi Arabia.
| | - Hamza Mostafa
- Biomarkers and Nutrimetabolomics Laboratory, Department of Nutrition, Food Sciences and Gastronomy, Food Innovation Network (XIA), Nutrition and Food Safety Research Institute (INSA), Facultat de Farmàcia i Ciències de l'Alimentació, Universitat de Barcelona (UB), 08028 Barcelona, Spain; Centro de Investigación Biomédica en Red de Fragilidad y Envejecimiento Saludable (CIBERFES), Instituto de Salud Carlos III, Madrid 28029, Spain
| | - Hani M J Khojah
- Department of Clinical and Hospital Pharmacy, College of Pharmacy, Taibah University, Madinah, Saudi Arabia
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23
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Effects of lifespan-extending interventions on cognitive healthspan. Expert Rev Mol Med 2022; 25:e2. [PMID: 36377361 DOI: 10.1017/erm.2022.36] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Ageing is known to be the primary risk factor for most neurodegenerative diseases, including Alzheimer's disease, Parkinson's disease and Huntington's disease. They are currently incurable and worsen over time, which has broad implications in the context of lifespan and healthspan extension. Adding years to life and even to physical health is suboptimal or even insufficient, if cognitive ageing is not adequately improved. In this review, we will examine how interventions that have the potential to extend lifespan in animals affect the brain, and if they would be able to thwart or delay the development of cognitive dysfunction and/or neurodegeneration. These interventions range from lifestyle (caloric restriction, physical exercise and environmental enrichment) through pharmacological (nicotinamide adenine dinucleotide precursors, resveratrol, rapamycin, metformin, spermidine and senolytics) to epigenetic reprogramming. We argue that while many of these interventions have clear potential to improve cognitive health and resilience, large-scale and long-term randomised controlled trials are needed, along with studies utilising washout periods to determine the effects of supplementation cessation, particularly in aged individuals.
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24
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Wu YG, Song LJ, Yin LJ, Yin JJ, Wang Q, Yu JZ, Xiao BG, Ma CG. The effects and potential of microglial polarization and crosstalk with other cells of the central nervous system in the treatment of Alzheimer's disease. Neural Regen Res 2022; 18:947-954. [PMID: 36254973 PMCID: PMC9827789 DOI: 10.4103/1673-5374.355747] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Microglia are resident immune cells in the central nervous system. During the pathogenesis of Alzheimer's disease, stimulatory factors continuously act on the microglia causing abnormal activation and unbalanced phenotypic changes; these events have become a significant and promising area of research. In this review, we summarize the effects of microglial polarization and crosstalk with other cells in the central nervous system in the treatment of Alzheimer's disease. Our literature search found that phenotypic changes occur continuously in Alzheimer's disease and that microglia exhibit extensive crosstalk with astrocytes, oligodendrocytes, neurons, and penetrated peripheral innate immune cells via specific signaling pathways and cytokines. Collectively, unlike previous efforts to modulate microglial phenotypes at a single level, targeting the phenotypes of microglia and the crosstalk with other cells in the central nervous system may be more effective in reducing inflammation in the central nervous system in Alzheimer's disease. This would establish a theoretical basis for reducing neuronal death from central nervous system inflammation and provide an appropriate environment to promote neuronal regeneration in the treatment of Alzheimer's disease.
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Affiliation(s)
- Yi-Ge Wu
- The Key Research Laboratory of Benefiting Qi for Acting Blood Circulation Method to Treat Multiple Sclerosis of State Administration of Traditional Chinese Medicine/Research Center of Neurobiology, Shanxi University of Chinese Medicine, Jinzhong, Shanxi Province, China
| | - Li-Juan Song
- The Key Research Laboratory of Benefiting Qi for Acting Blood Circulation Method to Treat Multiple Sclerosis of State Administration of Traditional Chinese Medicine/Research Center of Neurobiology, Shanxi University of Chinese Medicine, Jinzhong, Shanxi Province, China,Department of Physiology, Shanxi Medical University, Taiyuan, Shanxi Province, China
| | - Li-Jun Yin
- The Key Research Laboratory of Benefiting Qi for Acting Blood Circulation Method to Treat Multiple Sclerosis of State Administration of Traditional Chinese Medicine/Research Center of Neurobiology, Shanxi University of Chinese Medicine, Jinzhong, Shanxi Province, China
| | - Jun-Jun Yin
- The Key Research Laboratory of Benefiting Qi for Acting Blood Circulation Method to Treat Multiple Sclerosis of State Administration of Traditional Chinese Medicine/Research Center of Neurobiology, Shanxi University of Chinese Medicine, Jinzhong, Shanxi Province, China,Zhejiang Chinese Medical University, Hangzhou, Zhejiang Province, China
| | - Qing Wang
- The Key Research Laboratory of Benefiting Qi for Acting Blood Circulation Method to Treat Multiple Sclerosis of State Administration of Traditional Chinese Medicine/Research Center of Neurobiology, Shanxi University of Chinese Medicine, Jinzhong, Shanxi Province, China
| | - Jie-Zhong Yu
- Institute of Brain Science/Shanxi Key Laboratory of Inflammatory Neurodegenerative Diseases/Medical School, Shanxi Datong University, Datong, Shanxi Province, China
| | - Bao-Guo Xiao
- Institute of Neurology, Huashan Hospital, Institutes of Brain Science and State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai, China
| | - Cun-Gen Ma
- The Key Research Laboratory of Benefiting Qi for Acting Blood Circulation Method to Treat Multiple Sclerosis of State Administration of Traditional Chinese Medicine/Research Center of Neurobiology, Shanxi University of Chinese Medicine, Jinzhong, Shanxi Province, China,Institute of Brain Science/Shanxi Key Laboratory of Inflammatory Neurodegenerative Diseases/Medical School, Shanxi Datong University, Datong, Shanxi Province, China,Correspondence to: Cun-Gen Ma, .
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25
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Wang Q, Xue H, Yue Y, Hao S, Huang SH, Zhang Z. Role of mitophagy in the neurodegenerative diseases and its pharmacological advances: A review. Front Mol Neurosci 2022; 15:1014251. [PMID: 36267702 PMCID: PMC9578687 DOI: 10.3389/fnmol.2022.1014251] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 09/16/2022] [Indexed: 11/13/2022] Open
Abstract
Neurodegenerative diseases are a class of incurable and debilitating diseases characterized by progressive degeneration and death of cells in the central nervous system. They have multiple underlying mechanisms; however, they all share common degenerative features, such as mitochondrial dysfunction. According to recent studies, neurodegenerative diseases are associated with the accumulation of dysfunctional mitochondria. Selective autophagy of mitochondria, called mitophagy, can specifically degrade excess or dysfunctional mitochondria within cells. In this review, we highlight recent findings on the role of mitophagy in neurodegenerative disorders. Multiple studies were collected, including those related to the importance of mitochondria, the mechanism of mitophagy in protecting mitochondrial health, and canonical and non-canonical pathways in mitophagy. This review elucidated the important function of mitophagy in neurodegenerative diseases, discussed the research progress of mitophagy in neurodegenerative diseases, and summarized the role of mitophagy-related proteins in neurological diseases. In addition, we also highlight pharmacological advances in neurodegeneration.
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26
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Morawe MP, Liao F, Amberg W, van Bergeijk J, Chang R, Gulino M, Hamilton C, Hoft C, Lumpkin C, Mastis B, McGlame E, Nuber J, Plaas C, Ravikumar B, Roy K, Schanzenbächer M, Tierno J, Lakics V, Dellovade T, Townsend M. Pharmacological mTOR-inhibition facilitates clearance of AD-related tau aggregates in the mouse brain. Eur J Pharmacol 2022; 934:175301. [DOI: 10.1016/j.ejphar.2022.175301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 09/20/2022] [Accepted: 09/22/2022] [Indexed: 11/03/2022]
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27
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Cheng X, Wei Y, Qian Z, Han L. Autophagy Balances Neuroinflammation in Alzheimer's Disease. Cell Mol Neurobiol 2022; 43:1537-1549. [PMID: 35960407 DOI: 10.1007/s10571-022-01269-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2022] [Accepted: 07/29/2022] [Indexed: 01/20/2023]
Abstract
Autophagy is a highly evolutionary conserved process that degrades cytosolic macromolecules or damaged organelles (e.g., mitochondria), as well as intracellular pathogens for energy and survival. Dysfunction of autophagy has been associated with the pathologies of Alzheimer's disease (AD), including Aβ plaques and neurofibrillary tangles. Recently, the presence of sustained immune response in the brain has been considered a new core pathology in AD. Accumulating evidence suggests that autophagy activation may suppress inflammation response through degrading inflammasomes or pro-inflammatory cytokines and improving immune system function in both clinical trials and preclinical studies. This review provides an overview of updated information on autophagy and inflammation and their potential mediators in AD. In summary, we believe that understanding the relationship between autophagy and inflammation will provide insightful knowledge for future therapeutic implications in AD.
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Affiliation(s)
- Xuehua Cheng
- Department of TCM Geriatrics, Huadong Hospital Affiliated to Fudan University, Shanghai, 200040, People's Republic of China
| | - Yong Wei
- GeneScience Pharmaceuticals CoLtd., Changchun, 130012, People's Republic of China
| | - Zijun Qian
- Shanghai Municipal Hospital of Traditional Chinese Medicine, Shanghai, 200071, People's Republic of China
| | - Li Han
- Department of TCM Geriatrics, Huadong Hospital Affiliated to Fudan University, Shanghai, 200040, People's Republic of China.
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28
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Shi Q, Chang C, Saliba A, Bhat MA. Microglial mTOR Activation Upregulates Trem2 and Enhances β-Amyloid Plaque Clearance in the 5XFAD Alzheimer's Disease Model. J Neurosci 2022; 42:5294-5313. [PMID: 35672148 PMCID: PMC9270922 DOI: 10.1523/jneurosci.2427-21.2022] [Citation(s) in RCA: 39] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2021] [Revised: 05/04/2022] [Accepted: 05/05/2022] [Indexed: 02/08/2023] Open
Abstract
The mechanistic target of rapamycin (mTOR) signaling pathway plays a major role in key cellular processes including metabolism and differentiation; however, the role of mTOR in microglia and its importance in Alzheimer's disease (AD) have remained largely uncharacterized. We report that selective loss of Tsc1, a negative regulator of mTOR, in microglia in mice of both sexes, caused mTOR activation and upregulation of Trem2 with enhanced β-Amyloid (Aβ) clearance, reduced spine loss, and improved cognitive function in the 5XFAD AD mouse model. Combined loss of Tsc1 and Trem2 in microglia led to reduced Aβ clearance and increased Aβ plaque burden revealing that Trem2 functions downstream of mTOR. Tsc1 mutant microglia showed increased phagocytosis with upregulation of CD68 and Lamp1 lysosomal proteins. In vitro studies using Tsc1-deficient microglia revealed enhanced endocytosis of the lysosomal tracker indicator Green DND-26 suggesting increased lysosomal activity. Incubation of Tsc1-deficient microglia with fluorescent-labeled Aβ revealed enhanced Aβ uptake and clearance, which was blunted by rapamycin, an mTOR inhibitor. In vivo treatment of mice of relevant genotypes in the 5XFAD background with rapamycin, affected microglial activity, decreased Trem2 expression and reduced Aβ clearance causing an increase in Aβ plaque burden. Prolonged treatment with rapamycin caused even further reduction of mTOR activity, reduction in Trem2 expression, and increase in Aβ levels. Together, our findings reveal that mTOR signaling in microglia is critically linked to Trem2 regulation and lysosomal biogenesis, and that the upregulation of Trem2 in microglia through mTOR activation could be exploited toward better therapeutic avenues to Aβ-related AD pathologies.SIGNIFICANCE STATEMENT Mechanistic target of rapamycin (mTOR) signaling pathway is a key regulator for major cellular metabolic processes. However, the link between mTOR signaling and Alzheimer's disease (AD) is not well understood. In this study, we provide compelling in vivo evidence that mTOR activation in microglia would benefit β-Amyloid (Aβ)-related AD pathologies, as it upregulates Trem2, a key receptor for Aβ plaque uptake. Inhibition of mTOR pathway with rapamycin, a well-established immunosuppressant, downregulated Trem2 in microglia and reduced Aβ plaque clearance indicating that mTOR inactivation may be detrimental in Aβ-associated AD patients. This finding will have a significant public health impact and benefit, regarding the usage of rapamycin in AD patients, which we believe will aggravate the Aβ-related AD pathologies.
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Affiliation(s)
- Qian Shi
- Department of Cellular and Integrative Physiology, Long School of Medicine, University of Texas Health Science Center, San Antonio, Texas 78229
| | - Cheng Chang
- Department of Cellular and Integrative Physiology, Long School of Medicine, University of Texas Health Science Center, San Antonio, Texas 78229
| | - Afaf Saliba
- Department of Cellular and Integrative Physiology, Long School of Medicine, University of Texas Health Science Center, San Antonio, Texas 78229
| | - Manzoor A Bhat
- Department of Cellular and Integrative Physiology, Long School of Medicine, University of Texas Health Science Center, San Antonio, Texas 78229
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29
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Ondaro J, Hernandez-Eguiazu H, Garciandia-Arcelus M, Loera-Valencia R, Rodriguez-Gómez L, Jiménez-Zúñiga A, Goikolea J, Rodriguez-Rodriguez P, Ruiz-Martinez J, Moreno F, Lopez de Munain A, Holt IJ, Gil-Bea FJ, Gereñu G. Defects of Nutrient Signaling and Autophagy in Neurodegeneration. Front Cell Dev Biol 2022; 10:836196. [PMID: 35419363 PMCID: PMC8996160 DOI: 10.3389/fcell.2022.836196] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Accepted: 02/21/2022] [Indexed: 12/27/2022] Open
Abstract
Neurons are post-mitotic cells that allocate huge amounts of energy to the synthesis of new organelles and molecules, neurotransmission and to the maintenance of redox homeostasis. In neurons, autophagy is not only crucial to ensure organelle renewal but it is also essential to balance nutritional needs through the mobilization of internal energy stores. A delicate crosstalk between the pathways that sense nutritional status of the cell and the autophagic processes to recycle organelles and macronutrients is fundamental to guarantee the proper functioning of the neuron in times of energy scarcity. This review provides a detailed overview of the pathways and processes involved in the balance of cellular energy mediated by autophagy, which when defective, precipitate the neurodegenerative cascade of Parkinson’s disease, frontotemporal dementia, amyotrophic lateral sclerosis or Alzheimer’s disease.
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Affiliation(s)
- Jon Ondaro
- Department of Neuroscience, Biodonostia Health Research Institute (IIS Biodonostia), San Sebastian, Spain.,Center for Biomedical Research of Neurodegenerative Diseases (CIBERNED), Madrid, Spain
| | - Haizea Hernandez-Eguiazu
- Department of Neuroscience, Biodonostia Health Research Institute (IIS Biodonostia), San Sebastian, Spain.,Center for Biomedical Research of Neurodegenerative Diseases (CIBERNED), Madrid, Spain
| | - Maddi Garciandia-Arcelus
- Department of Neuroscience, Biodonostia Health Research Institute (IIS Biodonostia), San Sebastian, Spain.,Center for Biomedical Research of Neurodegenerative Diseases (CIBERNED), Madrid, Spain
| | - Raúl Loera-Valencia
- Department of Neurology, Care Sciences and Society, Center for Alzheimer Research, Karolinska Institutet (KI), Stockholm, Sweden
| | - Laura Rodriguez-Gómez
- Department of Neuroscience, Biodonostia Health Research Institute (IIS Biodonostia), San Sebastian, Spain.,Center for Biomedical Research of Neurodegenerative Diseases (CIBERNED), Madrid, Spain
| | - Andrés Jiménez-Zúñiga
- Department of Neuroscience, Biodonostia Health Research Institute (IIS Biodonostia), San Sebastian, Spain.,Center for Biomedical Research of Neurodegenerative Diseases (CIBERNED), Madrid, Spain
| | - Julen Goikolea
- Department of Neurology, Care Sciences and Society, Center for Alzheimer Research, Karolinska Institutet (KI), Stockholm, Sweden
| | - Patricia Rodriguez-Rodriguez
- Department of Neurology, Care Sciences and Society, Center for Alzheimer Research, Karolinska Institutet (KI), Stockholm, Sweden
| | - Javier Ruiz-Martinez
- Department of Neuroscience, Biodonostia Health Research Institute (IIS Biodonostia), San Sebastian, Spain.,Center for Biomedical Research of Neurodegenerative Diseases (CIBERNED), Madrid, Spain.,Donostia University Hospital, San Sebastian, Spain
| | - Fermín Moreno
- Department of Neuroscience, Biodonostia Health Research Institute (IIS Biodonostia), San Sebastian, Spain.,Center for Biomedical Research of Neurodegenerative Diseases (CIBERNED), Madrid, Spain.,Donostia University Hospital, San Sebastian, Spain
| | - Adolfo Lopez de Munain
- Department of Neuroscience, Biodonostia Health Research Institute (IIS Biodonostia), San Sebastian, Spain.,Center for Biomedical Research of Neurodegenerative Diseases (CIBERNED), Madrid, Spain.,Donostia University Hospital, San Sebastian, Spain
| | - Ian James Holt
- Department of Neuroscience, Biodonostia Health Research Institute (IIS Biodonostia), San Sebastian, Spain.,Center for Biomedical Research of Neurodegenerative Diseases (CIBERNED), Madrid, Spain.,Department of Clinical and Movement Neurosciences, Queen Square Institute of Neurology, Faculty of Brain Sciences, University College London, London, United Kingdom.,IKERBASQUE Basque Foundation for Science, Bilbao, Spain
| | - Francisco Javier Gil-Bea
- Department of Neuroscience, Biodonostia Health Research Institute (IIS Biodonostia), San Sebastian, Spain.,Center for Biomedical Research of Neurodegenerative Diseases (CIBERNED), Madrid, Spain
| | - Gorka Gereñu
- Department of Neuroscience, Biodonostia Health Research Institute (IIS Biodonostia), San Sebastian, Spain.,Center for Biomedical Research of Neurodegenerative Diseases (CIBERNED), Madrid, Spain.,Department of Physiology, Faculty of Medicine and Nursing, University of Basque Country (UPV-EHU), Leioa, Spain
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30
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Zhang Y, Wu KM, Yang L, Dong Q, Yu JT. Tauopathies: new perspectives and challenges. Mol Neurodegener 2022; 17:28. [PMID: 35392986 PMCID: PMC8991707 DOI: 10.1186/s13024-022-00533-z] [Citation(s) in RCA: 99] [Impact Index Per Article: 49.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Accepted: 03/23/2022] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Tauopathies are a class of neurodegenerative disorders characterized by neuronal and/or glial tau-positive inclusions. MAIN BODY Clinically, tauopathies can present with a range of phenotypes that include cognitive/behavioral-disorders, movement disorders, language disorders and non-specific amnestic symptoms in advanced age. Pathologically, tauopathies can be classified based on the predominant tau isoforms that are present in the inclusion bodies (i.e., 3R, 4R or equal 3R:4R ratio). Imaging, cerebrospinal fluid (CSF) and blood-based tau biomarkers have the potential to be used as a routine diagnostic strategy and in the evaluation of patients with tauopathies. As tauopathies are strongly linked neuropathologically and genetically to tau protein abnormalities, there is a growing interest in pursuing of tau-directed therapeutics for the disorders. Here we synthesize emerging lessons on tauopathies from clinical, pathological, genetic, and experimental studies toward a unified concept of these disorders that may accelerate the therapeutics. CONCLUSIONS Since tauopathies are still untreatable diseases, efforts have been made to depict clinical and pathological characteristics, identify biomarkers, elucidate underlying pathogenesis to achieve early diagnosis and develop disease-modifying therapies.
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Affiliation(s)
- Yi Zhang
- Department of Neurology and Institute of Neurology, Huashan Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Shanghai Medical College, Fudan University, National Center for Neurological Disorders, 12th Wulumuqi Zhong Road, Shanghai, 200040 China
| | - Kai-Min Wu
- Department of Neurology and Institute of Neurology, Huashan Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Shanghai Medical College, Fudan University, National Center for Neurological Disorders, 12th Wulumuqi Zhong Road, Shanghai, 200040 China
| | - Liu Yang
- Department of Neurology and Institute of Neurology, Huashan Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Shanghai Medical College, Fudan University, National Center for Neurological Disorders, 12th Wulumuqi Zhong Road, Shanghai, 200040 China
| | - Qiang Dong
- Department of Neurology and Institute of Neurology, Huashan Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Shanghai Medical College, Fudan University, National Center for Neurological Disorders, 12th Wulumuqi Zhong Road, Shanghai, 200040 China
| | - Jin-Tai Yu
- Department of Neurology and Institute of Neurology, Huashan Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Shanghai Medical College, Fudan University, National Center for Neurological Disorders, 12th Wulumuqi Zhong Road, Shanghai, 200040 China
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31
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Athar F, Templeman NM. C. elegans as a model organism to study female reproductive health. Comp Biochem Physiol A Mol Integr Physiol 2022; 266:111152. [PMID: 35032657 DOI: 10.1016/j.cbpa.2022.111152] [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: 11/02/2021] [Revised: 01/04/2022] [Accepted: 01/07/2022] [Indexed: 12/17/2022]
Abstract
Female reproductive health has been historically understudied and underfunded. Here, we present the advantages of using a free-living nematode, Caenorhabditis elegans, as an animal system to study fundamental aspects of female reproductive health. C. elegans is a powerful high-throughput model organism that shares key genetic and physiological similarities with humans. In this review, we highlight areas of pressing medical and biological importance in the 21st century within the context of female reproductive health. These include the decline in female reproductive capacity with increasing chronological age, reproductive dysfunction arising from toxic environmental insults, and cancers of the reproductive system. C. elegans has been instrumental in uncovering mechanistic insights underlying these processes, and has been valuable for developing and testing therapeutics to combat them. Adopting a convenient model organism such as C. elegans for studying reproductive health will encourage further research into this field, and broaden opportunities for making advancements into evolutionarily conserved mechanisms that control reproductive function.
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Affiliation(s)
- Faria Athar
- Department of Biology, University of Victoria, Victoria, British Columbia V8P 5C2, Canada
| | - Nicole M Templeman
- Department of Biology, University of Victoria, Victoria, British Columbia V8P 5C2, Canada.
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32
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Gourmaud S, Stewart DA, Irwin DJ, Roberts N, Barbour AJ, Eberwine G, O’Brien WT, Vassar R, Talos DM, Jensen FE. The role of mTORC1 activation in seizure-induced exacerbation of Alzheimer's disease. Brain 2022; 145:324-339. [PMID: 34264340 PMCID: PMC9126019 DOI: 10.1093/brain/awab268] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 06/04/2021] [Accepted: 06/21/2021] [Indexed: 11/13/2022] Open
Abstract
The risk of seizures is 10-fold higher in patients with Alzheimer's disease than the general population, yet the mechanisms underlying this susceptibility and the effects of these seizures are poorly understood. To elucidate the proposed bidirectional relationship between Alzheimer's disease and seizures, we studied human brain samples (n = 34) from patients with Alzheimer's disease and found that those with a history of seizures (n = 14) had increased amyloid-β and tau pathology, with upregulation of the mechanistic target of rapamycin (mTOR) pathway, compared with patients without a known history of seizures (n = 20). To establish whether seizures accelerate the progression of Alzheimer's disease, we induced chronic hyperexcitability in the five times familial Alzheimer's disease mouse model by kindling with the chemoconvulsant pentylenetetrazol and observed that the mouse model exhibited more severe seizures than the wild-type. Furthermore, kindled seizures exacerbated later cognitive impairment, Alzheimer's disease neuropathology and mTOR complex 1 activation. Finally, we demonstrated that the administration of the mTOR inhibitor rapamycin following kindled seizures rescued enhanced remote and long-term memory deficits associated with earlier kindling and prevented seizure-induced increases in Alzheimer's disease neuropathology. These data demonstrated an important link between chronic hyperexcitability and progressive Alzheimer's disease pathology and suggest a mechanism whereby rapamycin may serve as an adjunct therapy to attenuate progression of the disease.
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Affiliation(s)
- Sarah Gourmaud
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - David A Stewart
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Duke University School of Medicine, Durham, NC 27708, USA
| | - David J Irwin
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Penn Frontotemporal Degeneration Center, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Nicholas Roberts
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Aaron J Barbour
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Grace Eberwine
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - William T O’Brien
- Neurobehavior Testing Core, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Robert Vassar
- Department of Cell and Molecular Biology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Delia M Talos
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Frances E Jensen
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
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Lai C, Chen Z, Ding Y, Chen Q, Su S, Liu H, Ni R, Tang Z. Rapamycin Attenuated Zinc-Induced Tau Phosphorylation and Oxidative Stress in Rats: Involvement of Dual mTOR/p70S6K and Nrf2/HO-1 Pathways. Front Immunol 2022; 13:782434. [PMID: 35197970 PMCID: PMC8858937 DOI: 10.3389/fimmu.2022.782434] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 01/13/2022] [Indexed: 01/01/2023] Open
Abstract
Alzheimer's disease is pathologically characterized by abnormal accumulation of amyloid-beta plaques, neurofibrillary tangles, oxidative stress, neuroinflammation, and neurodegeneration. Metal dysregulation, including excessive zinc released by presynaptic neurons, plays an important role in tau pathology and oxidase activation. The activities of mammalian target of rapamycin (mTOR)/ribosomal S6 protein kinase (p70S6K) are elevated in the brains of patients with Alzheimer's disease. Zinc induces tau hyperphosphorylation via mTOR/P70S6K activation in vitro. However, the involvement of the mTOR/P70S6K pathway in zinc-induced oxidative stress, tau degeneration, and synaptic and cognitive impairment has not been fully elucidated in vivo. Here, we assessed the effect of pathological zinc concentrations in SH-SY5Y cells by using biochemical assays and immunofluorescence staining. Rats (n = 18, male) were laterally ventricularly injected with zinc, treated with rapamycin (intraperitoneal injection) for 1 week, and assessed using the Morris water maze. Evaluation of oxidative stress, tau phosphorylation, and synaptic impairment was performed using the hippocampal tissue of the rats by biochemical assays and immunofluorescence staining. The results from the Morris water maze showed that the capacity of spatial memory was impaired in zinc-treated rats. Zinc sulfate significantly increased the levels of P-mTOR Ser2448, P-p70S6K Thr389, and P-tau Ser356 and decreased the levels of nuclear factor erythroid 2-related factor-2 (Nrf2) and heme oxygenase-1 (HO-1) in SH-SY5Y cells and in zinc-treated rats compared with the control groups. Increased expression of reactive oxygen species was observed in zinc sulfate-induced SH-SY5Y cells and in the hippocampus of zinc-injected rats. Rapamycin, an inhibitor of mTOR, rescued zinc-induced increases in mTOR/p70S6K activation, tau phosphorylation, and oxidative stress, and Nrf2/HO-1 inactivation, cognitive impairment, and synaptic impairment reduced the expression of synapse-related proteins in zinc-injected rats. In conclusion, our findings imply that rapamycin prevents zinc-induced cognitive impairment and protects neurons from tau pathology, oxidative stress, and synaptic impairment by decreasing mTOR/p70S6K hyperactivity and increasing Nrf2/HO-1 activity.
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Affiliation(s)
- Chencen Lai
- Key Laboratory of Endemic and Ethnic Diseases, Ministry of Education & Key Laboratory of Medical Molecular Biology of Guizhou Province, Guizhou Medical University, Guiyang, China
- Department of Nosocomial Infection, The First Affiliated Hospital of Guizhou University of Traditional Chinese Medicine, Guiyang, China
| | - Zhuyi Chen
- Key Laboratory of Endemic and Ethnic Diseases, Ministry of Education & Key Laboratory of Medical Molecular Biology of Guizhou Province, Guizhou Medical University, Guiyang, China
| | - Yuanting Ding
- Department of Nosocomial Infection, The First Affiliated Hospital of Guizhou University of Traditional Chinese Medicine, Guiyang, China
| | - Qian Chen
- Department of Nosocomial Infection, The First Affiliated Hospital of Guizhou University of Traditional Chinese Medicine, Guiyang, China
| | - Songbai Su
- Department of Nosocomial Infection, The First Affiliated Hospital of Guizhou University of Traditional Chinese Medicine, Guiyang, China
| | - Heng Liu
- Department of Anesthesiology, Tongren Municipal People’s Hospital, Tongren, China
| | - Ruiqing Ni
- Institute for Regenerative Medicine, University of Zurich, Zurich, Switzerland
- Institute for Biomedical Engineering, Eidgenössische Technische Hochschule Zürich (ETH) and University of Zurich, Zurich, Switzerland
| | - Zhi Tang
- Key Laboratory of Endemic and Ethnic Diseases, Ministry of Education & Key Laboratory of Medical Molecular Biology of Guizhou Province, Guizhou Medical University, Guiyang, China
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Antonella C, Sandro M, Vincenzo C, Martina S, Alessandra E, Gennaro N, Eduardo N, Elena P, Teresa PM, Maria DR, Elvira DL, Cristina SN, Luis MD. Fluoxetine ameliorates Mucopolysaccharidosis type IIIA. Mol Ther 2022; 30:1432-1450. [PMID: 35121108 PMCID: PMC9077373 DOI: 10.1016/j.ymthe.2022.01.037] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 12/21/2021] [Accepted: 01/28/2022] [Indexed: 11/26/2022] Open
Abstract
Mucopolysaccharidosis type IIIA (MPS-IIIA) is an autosomal recessive disorder caused by mutations in SGSH involved in the degradation of heparan sulfate. MPS-IIIA presents severe neurological symptoms such as progressive developmental delay and cognitive decline, for which there is currently no treatment. Brain targeting represents the main challenge for therapeutics to treat MPS-IIIA, and the development of small-molecule-based treatments able to reach the CNS could be a relevant advance for therapy. Using cell-based high content imaging to survey clinically approved drugs in MPS-IIIA cells, we identified fluoxetine, a selective serotonin reuptake inhibitor. Fluoxetine increases lysosomal and autophagic functions via TFEB activation through a RagC-dependent mechanism. Mechanistically, fluoxetine increases lysosomal exocytosis in mouse embryonic fibroblasts from MPS-IIIA mice, suggesting that this process may be responsible for heparan sulfate clearance. In vivo, fluoxetine ameliorates somatic and brain pathology in a mouse model of MPS-IIIA by decreasing the accumulation of glycosaminoglycans and aggregated autophagic substrates, reducing inflammation, and slowing down cognitive deterioration. We repurposed fluoxetine for potential therapeutics to treat human MPS-IIIA disease.
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Wei H, Peng Z, Guo J, Chen L, Shao K. Downregulation of miR-338-3p alleviates neuronal ischemic injury by decreasing cPKCγ-Mediated autophagy through the Akt/mTOR pathway. Neurochem Int 2022; 154:105279. [PMID: 35021067 DOI: 10.1016/j.neuint.2022.105279] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 01/05/2022] [Accepted: 01/06/2022] [Indexed: 11/28/2022]
Abstract
Ischemic stroke is the leading cause of mortality and disability in aging populations. Dysregulation of microRNA is associated with the pathophysiology of ischemic brain injury. Previously, we found that miR-338-3p was prominently downregulated in OGD-treated neurons, which indicates that miR-338-3P potentially plays an important role in ischemic injury. Furthermore, we performed a bioinformatic analysis and found that conventional protein kinase cγ (cPKCγ), an important autophagy regulator, is a potential target of miR-338-3p, and it is upregulated in neurons after ischemic injury. Therefore, we speculated that miR-338-3P may play a role in neuronal autophagy associated with ischemic brain injury by regulating cPKCγ levels. In the present study, oxygen glucose deprivation was used to test this hypothesis. Our results show that miR-338-3p expression is prominently downregulated after OGD. Additionally, miR-338-3p knockdown attenuated ischemic injury and simultaneously reduced the microtubule-associated protein 1 light chain 3 (LC3)-II/LC3-I ratio, which contributes to neuronal survival after ischemia. Moreover, the cPKCγ protein level increased, and miR-338-3p recognized the 3'-untranslated region of the cPKCγ messenger RNA (mRNA) and negatively regulated the cPKCγ protein level by promoting the degradation of its mRNA. In addition, Lv-cPKCγ blocked the pri-miR-338-3p-induced decrease of the Akt and mammalian target of rapamycin (mTOR) phosphorylation levels, as well as the accompanying increase of the LC3-II/LC3-I ratio, thereby alleviating ischemic injury. This suggests that miR-338-3p downregulation following ischemic injury alleviates neuronal injury by targeting cPKCγ, thereby activating the Akt/mTOR signaling cascade and decreasing downstream autophagy. These results provide a potential therapeutic target for ischemic stroke.
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Affiliation(s)
- Haiping Wei
- Department of Neurology, Lanzhou University Second Hospital, Lanzhou, 730030, PR China.
| | - Zhifeng Peng
- Department of Physiology, Medical School, Shanxi Datong University, Datong, 037009, PR China
| | - Jia Guo
- Department of Neurology, Lanzhou University Second Hospital, Lanzhou, 730030, PR China
| | - Lixia Chen
- Department of Neurology, Lanzhou University Second Hospital, Lanzhou, 730030, PR China
| | - Kangmei Shao
- Department of Neurology, Lanzhou University Second Hospital, Lanzhou, 730030, PR China
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Carosi JM, Fourrier C, Bensalem J, Sargeant TJ. The mTOR-lysosome axis at the centre of ageing. FEBS Open Bio 2021; 12:739-757. [PMID: 34878722 PMCID: PMC8972043 DOI: 10.1002/2211-5463.13347] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 11/23/2021] [Accepted: 12/07/2021] [Indexed: 01/10/2023] Open
Abstract
Age‐related diseases represent some of the largest unmet clinical needs of our time. While treatment of specific disease‐related signs has had some success (for example, the effect of statin drugs on slowing progression of atherosclerosis), slowing biological ageing itself represents a target that could significantly increase health span and reduce the prevalence of multiple age‐related diseases. Mechanistic target of rapamycin complex 1 (mTORC1) is known to control fundamental processes in ageing: inhibiting this signalling complex slows biological ageing, reduces age‐related disease pathology and increases lifespan in model organisms. How mTORC1 inhibition achieves this is still subject to ongoing research. However, one mechanism by which mTORC1 inhibition is thought to slow ageing is by activating the autophagy–lysosome pathway. In this review, we examine the special bidirectional relationship between mTORC1 and the lysosome. In cells, mTORC1 is located on lysosomes. From this advantageous position, it directly controls the autophagy–lysosome pathway. However, the lysosome also controls mTORC1 activity in numerous ways, creating a special two‐way relationship. We then explore specific examples of how inhibition of mTORC1 and activation of the autophagy–lysosome pathway slow the molecular hallmarks of ageing. This body of literature demonstrates that the autophagy–lysosome pathway represents an excellent target for treatments that seek to slow biological ageing and increase health span in humans.
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Affiliation(s)
- Julian M Carosi
- Lysosomal Health in Ageing, Hopwood Centre for Neurobiology, Lifelong Health Theme, SAHMRI, Adelaide, Australia
| | - Célia Fourrier
- Lysosomal Health in Ageing, Hopwood Centre for Neurobiology, Lifelong Health Theme, SAHMRI, Adelaide, Australia
| | - Julien Bensalem
- Lysosomal Health in Ageing, Hopwood Centre for Neurobiology, Lifelong Health Theme, SAHMRI, Adelaide, Australia
| | - Timothy J Sargeant
- Lysosomal Health in Ageing, Hopwood Centre for Neurobiology, Lifelong Health Theme, SAHMRI, Adelaide, Australia
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Imbimbo BP, Ippati S, Watling M, Balducci C. A critical appraisal of tau-targeting therapies for primary and secondary tauopathies. Alzheimers Dement 2021; 18:1008-1037. [PMID: 34533272 DOI: 10.1002/alz.12453] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 07/20/2021] [Accepted: 07/26/2021] [Indexed: 12/17/2022]
Abstract
INTRODUCTION Primary tauopathies are neurological disorders in which tau protein deposition is the predominant pathological feature. Alzheimer's disease is a secondary tauopathy with tau forming hyperphosphorylated insoluble aggregates. Tau pathology can propagate from region to region in the brain, while alterations in tau processing may impair tau physiological functions. METHODS We reviewed literature on tau biology and anti-tau drugs using PubMed, meeting abstracts, and ClnicalTrials.gov. RESULTS The past 15 years have seen >30 drugs interfering with tau aggregation, processing, and accumulation reaching the clinic. Initial results with tau aggregation inhibitors and anti-tau monoclonal antibodies have not shown clinical efficacy. DISCUSSION The reasons for these clinical failures are unclear but could be linked to the clearing of physiological forms of tau by non-specific drugs. Research is now concentrating efforts on developing reliable translational animal models and selective compounds targeting specific tau epitopes, neurotoxic tau aggregates, and post-translational tau modifications.
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Affiliation(s)
- Bruno P Imbimbo
- Department of Research & Development, Chiesi Farmaceutici, Parma, Italy
| | - Stefania Ippati
- San Raffaele Scientific Institute, San Raffaele Hospital, Milan, Italy
| | - Mark Watling
- CNS & Pain Department, TranScrip Ltd, Reading, UK
| | - Claudia Balducci
- Department of Neuroscience, Istituto di Ricerche Farmacologiche "Mario Negri" IRCCS, Milan, Italy
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The Amino Acid-mTORC1 Pathway Mediates APEC TW-XM-Induced Inflammation in bEnd.3 Cells. Int J Mol Sci 2021; 22:ijms22179245. [PMID: 34502151 PMCID: PMC8431488 DOI: 10.3390/ijms22179245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 08/19/2021] [Accepted: 08/24/2021] [Indexed: 11/16/2022] Open
Abstract
The blood-brain barrier (BBB) is key to establishing and maintaining homeostasis in the central nervous system (CNS); meningitis bacterial infection can disrupt the integrity of BBB by inducing an inflammatory response. The changes in the cerebral uptake of amino acids may contribute to inflammatory response during infection and were accompanied by high expression of amino acid transporters leading to increased amino acid uptake. However, it is unclear whether amino acid uptake is changed and how to affect inflammatory responses in mouse brain microvascular endothelial (bEnd.3) cells in response to Avian Pathogenic Escherichia coli TW-XM (APEC XM) infection. Here, we firstly found that APEC XM infection could induce serine (Ser) and glutamate (Glu) transport from extracellular into intracellular in bEnd.3 cells. Meanwhile, we also shown that the expression sodium-dependent neutral amino acid transporter 2 (SNAT2) for Ser and excitatory amino acid transporter 4 (EAAT4) for Glu was also significantly elevated during infection. Then, in amino acid deficiency or supplementation medium, we found that Ser or Glu transport were involving in increasing SNAT2 or EAAT4 expression, mTORC1 (mechanistic target of rapamycin complex 1) activation and inflammation, respectively. Of note, Ser or Glu transport were inhibited after SNAT2 silencing or EAAT4 silencing, resulting in inhibition of mTORC1 pathway activation, and inflammation compared with the APEC XM infection group. Moreover, pEGFP-SNAT2 overexpression and pEGFP-EAAT4 overexpression in bEnd.3 cells all could promote amino acid uptake, activation of the mTORC1 pathway and inflammation during infection. We further found mTORC1 silencing could inhibit inflammation, the expression of SNAT2 and EAAT4, and amino acid uptake. Taken together, our results demonstrated that APEC TW-XM infection can induce Ser or Glu uptake depending on amino acid transporters transportation, and then activate amino acid-mTORC1 pathway to induce inflammation in bEnd.3 cells.
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Hattersley KJ, Carosi JM, Hein LK, Bensalem J, Sargeant TJ. PICALM regulates cathepsin D processing and lysosomal function. Biochem Biophys Res Commun 2021; 570:103-109. [PMID: 34311200 DOI: 10.1016/j.bbrc.2021.07.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Accepted: 07/07/2021] [Indexed: 10/20/2022]
Abstract
Degradation and clearance of cellular waste in the autophagic and endo-lysosomal systems is important for normal physiology and prevention of common late-onset diseases such as Alzheimer's disease (AD). Phosphatidylinostol-binding clathrin assembly protein (PICALM) is a robust AD risk factor gene and encodes an endosomal protein clathrin-binding cytosolic protein, reduction of which is known to exacerbate tauopathy. Although PICALM is known to regulate initiation of autophagy, its role in maturation of lysosomal enzymes required for proteolysis has not been studied. We sought to determine the importance of PICALM for cellular degradative function by disrupting exon 1 of PICALM using CRISPR/Cas9 in HeLa cells. PICALM disruption increased numbers of early endosomes. Proteomic analysis of endosome-enriched samples showed that disrupting exon 1 of PICALM increased the abundance of lysosomal enzymes in these organelles, and western blotting revealed disruption to processing and maturation of the lysosomal protease, cathepsin D, and a deficit in autophagy. This study shows PICALM is important for the correct maturation of lysosomal enzymes and efficient proteolytic function in the lysosome.
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Affiliation(s)
- Kathryn J Hattersley
- Lysosomal Health in Ageing, Hopwood Centre for Neurobiology, Lifelong Health Theme, South Australian Health and Medical Research Institute, North Terrace, Adelaide, SA, 5000, Australia
| | - Julian M Carosi
- Lysosomal Health in Ageing, Hopwood Centre for Neurobiology, Lifelong Health Theme, South Australian Health and Medical Research Institute, North Terrace, Adelaide, SA, 5000, Australia
| | - Leanne K Hein
- Lysosomal Health in Ageing, Hopwood Centre for Neurobiology, Lifelong Health Theme, South Australian Health and Medical Research Institute, North Terrace, Adelaide, SA, 5000, Australia
| | - Julien Bensalem
- Lysosomal Health in Ageing, Hopwood Centre for Neurobiology, Lifelong Health Theme, South Australian Health and Medical Research Institute, North Terrace, Adelaide, SA, 5000, Australia
| | - Timothy J Sargeant
- Lysosomal Health in Ageing, Hopwood Centre for Neurobiology, Lifelong Health Theme, South Australian Health and Medical Research Institute, North Terrace, Adelaide, SA, 5000, Australia.
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Selvarani R, Mohammed S, Richardson A. Effect of rapamycin on aging and age-related diseases-past and future. GeroScience 2021; 43:1135-1158. [PMID: 33037985 PMCID: PMC8190242 DOI: 10.1007/s11357-020-00274-1] [Citation(s) in RCA: 114] [Impact Index Per Article: 38.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 09/21/2020] [Indexed: 12/19/2022] Open
Abstract
In 2009, rapamycin was reported to increase the lifespan of mice when implemented later in life. This observation resulted in a sea-change in how researchers viewed aging. This was the first evidence that a pharmacological agent could have an impact on aging when administered later in life, i.e., an intervention that did not have to be implemented early in life before the negative impact of aging. Over the past decade, there has been an explosion in the number of reports studying the effect of rapamycin on various diseases, physiological functions, and biochemical processes in mice. In this review, we focus on those areas in which there is strong evidence for rapamycin's effect on aging and age-related diseases in mice, e.g., lifespan, cardiac disease/function, central nervous system, immune system, and cell senescence. We conclude that it is time that pre-clinical studies be focused on taking rapamycin to the clinic, e.g., as a potential treatment for Alzheimer's disease.
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Affiliation(s)
- Ramasamy Selvarani
- Department of Biochemistry & Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Sabira Mohammed
- Department of Biochemistry & Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Arlan Richardson
- Department of Biochemistry & Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.
- Oklahoma City VA Medical Center, Oklahoma City, OK, USA.
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Stanciu GD, Rusu RN, Bild V, Filipiuc LE, Tamba BI, Ababei DC. Systemic Actions of SGLT2 Inhibition on Chronic mTOR Activation as a Shared Pathogenic Mechanism between Alzheimer's Disease and Diabetes. Biomedicines 2021; 9:biomedicines9050576. [PMID: 34069618 PMCID: PMC8160780 DOI: 10.3390/biomedicines9050576] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 05/15/2021] [Accepted: 05/17/2021] [Indexed: 02/07/2023] Open
Abstract
Alzheimer's disease (AD) affects tens of millions of people worldwide. Despite the advances in understanding the disease, there is an increased urgency for pharmacological approaches able of impacting its onset and progression. With a multifactorial nature, high incidence and prevalence in later years of life, there is growing evidence highlighting a relationship between metabolic dysfunction related to diabetes and subject's susceptibility to develop AD. The link seems so solid that sometimes AD and type 3 diabetes are used interchangeably. A candidate for a shared pathogenic mechanism linking these conditions is chronically-activated mechanistic target of rapamycin (mTOR). Chronic activation of unrestrained mTOR could be responsible for sustaining metabolic dysfunction that causes the breakdown of the blood-brain barrier, tau hyperphosphorylation and senile plaques formation in AD. It has been suggested that inhibition of sodium glucose cotransporter 2 (SGLT2) mediated by constant glucose loss, may restore mTOR cycle via nutrient-driven, preventing or even decreasing the AD progression. Currently, there is an unmet need for further research insight into molecular mechanisms that drive the onset and AD advancement as well as an increase in efforts to expand the testing of potential therapeutic strategies aimed to counteract disease progression in order to structure effective therapies.
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Affiliation(s)
- Gabriela Dumitrita Stanciu
- Center for Advanced Research and Development in Experimental Medicine (CEMEX), Grigore T. Popa University of Medicine and Pharmacy, 16 Universitatii Street, 700115 Iasi, Romania; (G.D.S.); (V.B.); (L.E.F.)
| | - Razvan Nicolae Rusu
- Pharmacodynamics and Clinical Pharmacy Department, Grigore T. Popa University of Medicine and Pharmacy, 16 Universitatii Street, 700115 Iasi, Romania; (R.N.R.); (D.C.A.)
| | - Veronica Bild
- Center for Advanced Research and Development in Experimental Medicine (CEMEX), Grigore T. Popa University of Medicine and Pharmacy, 16 Universitatii Street, 700115 Iasi, Romania; (G.D.S.); (V.B.); (L.E.F.)
- Pharmacodynamics and Clinical Pharmacy Department, Grigore T. Popa University of Medicine and Pharmacy, 16 Universitatii Street, 700115 Iasi, Romania; (R.N.R.); (D.C.A.)
| | - Leontina Elena Filipiuc
- Center for Advanced Research and Development in Experimental Medicine (CEMEX), Grigore T. Popa University of Medicine and Pharmacy, 16 Universitatii Street, 700115 Iasi, Romania; (G.D.S.); (V.B.); (L.E.F.)
- Department of Pharmacology, Clinical Pharmacology and Algesiology, Grigore T. Popa University of Medicine and Pharmacy, 16 Universitatii Street, 700115 Iasi, Romania
| | - Bogdan-Ionel Tamba
- Center for Advanced Research and Development in Experimental Medicine (CEMEX), Grigore T. Popa University of Medicine and Pharmacy, 16 Universitatii Street, 700115 Iasi, Romania; (G.D.S.); (V.B.); (L.E.F.)
- Department of Pharmacology, Clinical Pharmacology and Algesiology, Grigore T. Popa University of Medicine and Pharmacy, 16 Universitatii Street, 700115 Iasi, Romania
- Correspondence:
| | - Daniela Carmen Ababei
- Pharmacodynamics and Clinical Pharmacy Department, Grigore T. Popa University of Medicine and Pharmacy, 16 Universitatii Street, 700115 Iasi, Romania; (R.N.R.); (D.C.A.)
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Mitochondrial dysfunction: A potential target for Alzheimer's disease intervention and treatment. Drug Discov Today 2021; 26:1991-2002. [PMID: 33962036 DOI: 10.1016/j.drudis.2021.04.025] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2020] [Revised: 02/05/2021] [Accepted: 04/27/2021] [Indexed: 02/07/2023]
Abstract
Alzheimer's disease (AD) is an irreversible neurodegenerative brain disorder which manifests as a progressive decline in cognitive function. Mitochondrial dysfunction plays a critical role in the early stages of AD, and advances the progression of this age-related neurodegenerative disorder. Therefore, it can be a potential target for interventions to treat AD. Several therapeutic strategies to target mitochondrial dysfunction have gained significant attention in the preclinical stage, but the clinical trials performed to date have shown little progress. Thus, we discuss the mechanisms and strategies of different therapeutic agents for targeting mitochondrial dysfunction in AD. We hope that this review will inspire and guide the development of efficient AD drugs in the future.
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Pan XJ, Misrani A, Tabassum S, Yang L. Mitophagy pathways and Alzheimer's disease: From pathogenesis to treatment. Mitochondrion 2021; 59:37-47. [PMID: 33872797 DOI: 10.1016/j.mito.2021.04.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 04/08/2021] [Accepted: 04/13/2021] [Indexed: 12/24/2022]
Abstract
Alzheimer's disease (AD) is an age-dependent, incurable mental illness that is associated with the accumulation of aggregates of amyloid-beta (Aβ) and hyperphosphorylated tau fragments (p-tau). Detailed studies on postmortem AD brains, cell lines, and mouse models of AD have shown that numerous cellular alterations, including mitochondrial deficits, synaptic disruption and glial/astrocytic activation, are involved in the disease process. Mitophagy is a cellular process by which damaged/weakened mitochondria are selectively eliminated from the cell. In AD, impairments in mitophagy trigger the gradual accumulation of defective mitochondria. This review will focus on the recent progress in understanding the molecular mechanisms and pathological role of mitophagy and its implications for AD pathogenesis. We will also discuss the novel concept of the regulation of mitophagy as a therapeutic avenue for the prevention and treatment of AD.
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Affiliation(s)
- Xian-Ji Pan
- Precise Genome Engineering Center, School of Life Sciences, Guangzhou University, Guangzhou 510006, China
| | - Afzal Misrani
- Precise Genome Engineering Center, School of Life Sciences, Guangzhou University, Guangzhou 510006, China
| | - Sidra Tabassum
- Precise Genome Engineering Center, School of Life Sciences, Guangzhou University, Guangzhou 510006, China
| | - Li Yang
- Precise Genome Engineering Center, School of Life Sciences, Guangzhou University, Guangzhou 510006, China.
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Towner RA, Gulej R, Zalles M, Saunders D, Smith N, Lerner M, Morton KA, Richardson A. Rapamycin restores brain vasculature, metabolism, and blood-brain barrier in an inflammaging model. GeroScience 2021; 43:563-578. [PMID: 33846885 PMCID: PMC8110648 DOI: 10.1007/s11357-021-00363-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Accepted: 04/06/2021] [Indexed: 02/08/2023] Open
Abstract
Rapamycin (RAPA) is found to have neuro-protective properties in various neuroinflammatory pathologies, including brain aging. With magnetic resonance imaging (MRI) techniques, we investigated the effect of RAPA in a lipopolysaccharide (LPS)-induced inflammaging model in rat brains. Rats were exposed to saline (control), or LPS alone or LPS combined with RAPA treatment (via food over 6 weeks). Arterial spin labeling (ASL) perfusion imaging was used to measure relative cerebral blood flow (rCBF). MR spectroscopy (MRS) was used to measure brain metabolite levels. Contrast-enhanced MRI (CE-MRI) was used to assess blood-brain barrier (BBB) permeability. Immunohistochemistry (IHC) was used to confirm neuroinflammation. RAPA restored NF-κB and HIF-1α to normal levels. RAPA was able to significantly restore rCBF in the cerebral cortex post-LPS exposure (p < 0.05), but not in the hippocampus. In the hippocampus, RAPA was able to restore total creatine (Cr) acutely, and N-acetyl aspartate (NAA) at 6 weeks, post-LPS. Myo-inositol (Myo-Ins) levels were found to decrease with RAPA treatment acutely post-LPS. RAPA was also able to significantly restore the BBB acutely post-LPS in both the cortex and hippocampus (p < 0.05 for both). RAPA was found to increase the percent change in BOLD signal in the cortex at 3 weeks, and in the hippocampus at 6 weeks post-LPS, compared to LPS alone. RAPA treatment also restored the neuronal and macro-vascular marker, EphB2, back to normal levels. These results indicate that RAPA may play an important therapeutic role in inhibiting neuroinflammation by normalizing brain vascularity, BBB, and some brain metabolites, and has a high translational capability.
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Affiliation(s)
- Rheal A Towner
- Advanced Magnetic Resonance Center, Oklahoma Medical Research Foundation, 825 NE 13th Street, Oklahoma City, OK, 73104, USA.
- Neuroscience Program, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.
- Oklahoma Nathan Shock Center for Aging, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.
| | - Rafal Gulej
- Advanced Magnetic Resonance Center, Oklahoma Medical Research Foundation, 825 NE 13th Street, Oklahoma City, OK, 73104, USA
| | - Michelle Zalles
- Advanced Magnetic Resonance Center, Oklahoma Medical Research Foundation, 825 NE 13th Street, Oklahoma City, OK, 73104, USA
- Neuroscience Program, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Debra Saunders
- Advanced Magnetic Resonance Center, Oklahoma Medical Research Foundation, 825 NE 13th Street, Oklahoma City, OK, 73104, USA
| | - Nataliya Smith
- Advanced Magnetic Resonance Center, Oklahoma Medical Research Foundation, 825 NE 13th Street, Oklahoma City, OK, 73104, USA
| | - Megan Lerner
- Department of Surgery, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Kathryn A Morton
- Department of Radiology and Imaging Sciences, University of Utah School of Medicine, Salt Lake City, UT, USA
| | - Arlan Richardson
- Oklahoma Nathan Shock Center for Aging, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
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45
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Bensalem J, Fourrier C, Hein LK, Hassiotis S, Proud CG, Sargeant TJ. Inhibiting mTOR activity using AZD2014 increases autophagy in the mouse cerebral cortex. Neuropharmacology 2021; 190:108541. [PMID: 33794244 DOI: 10.1016/j.neuropharm.2021.108541] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2020] [Revised: 03/16/2021] [Accepted: 03/24/2021] [Indexed: 01/18/2023]
Abstract
Autophagy is a catabolic process that collects and degrades damaged or unwanted cellular materials such as protein aggregates. Defective brain autophagy has been linked to diseases such as Alzheimer's disease. Autophagy is regulated by the protein kinase mTOR (mechanistic target of rapamycin). Although already demonstrated in vitro, it remains contentious whether inhibiting mTOR can enhance autophagy in the brain. To address this, mice were intraperitoneally injected with the mTOR inhibitor AZD2014 for seven days. mTOR complex 1 (mTORC1) activity was decreased in liver and brain. Autophagic activity was increased by AZD2014 in both organs, as measured by immunoblotting for LC3 (microtubule-associated proteins-1A/1B light chain 3B) and measurement of autophagic flux in the cerebral cortex of transgenic mice expressing the EGFP-mRFP-LC3B transgene. mTOR activity was shown to correlate with changes in LC3. Thus, we show it is possible to promote autophagy in the brain using AZD2014, which will be valuable in tackling conditions associated with defective autophagy, especially neurodegeneration.
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Affiliation(s)
- Julien Bensalem
- Lysosomal Health in Ageing, Hopwood Centre for Neurobiology, Lifelong Health Theme, South Australian Health and Medical Research Institute, North Terrace, Adelaide, Australia
| | - Célia Fourrier
- Lysosomal Health in Ageing, Hopwood Centre for Neurobiology, Lifelong Health Theme, South Australian Health and Medical Research Institute, North Terrace, Adelaide, Australia
| | - Leanne K Hein
- Lysosomal Health in Ageing, Hopwood Centre for Neurobiology, Lifelong Health Theme, South Australian Health and Medical Research Institute, North Terrace, Adelaide, Australia
| | - Sofia Hassiotis
- Lysosomal Health in Ageing, Hopwood Centre for Neurobiology, Lifelong Health Theme, South Australian Health and Medical Research Institute, North Terrace, Adelaide, Australia
| | - Christopher G Proud
- Nutrition, Diabetes and Gut Health, Lifelong Health Theme, South Australian Health and Medical Research Institute, North Terrace, Adelaide, Australia
| | - Timothy J Sargeant
- Lysosomal Health in Ageing, Hopwood Centre for Neurobiology, Lifelong Health Theme, South Australian Health and Medical Research Institute, North Terrace, Adelaide, Australia.
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46
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Campagno KE, Mitchell CH. The P2X 7 Receptor in Microglial Cells Modulates the Endolysosomal Axis, Autophagy, and Phagocytosis. Front Cell Neurosci 2021; 15:645244. [PMID: 33790743 PMCID: PMC8005553 DOI: 10.3389/fncel.2021.645244] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Accepted: 02/22/2021] [Indexed: 01/18/2023] Open
Abstract
Microglial cells regulate neural homeostasis by coordinating both immune responses and clearance of debris, and the P2X7 receptor for extracellular ATP plays a central role in both functions. The P2X7 receptor is primarily known in microglial cells for its immune signaling and NLRP3 inflammasome activation. However, the receptor also affects the clearance of extracellular and intracellular debris through modifications of lysosomal function, phagocytosis, and autophagy. In the absence of an agonist, the P2X7 receptor acts as a scavenger receptor to phagocytose material. Transient receptor stimulation induces autophagy and increases LC3-II levels, likely through calcium-dependent phosphorylation of AMPK, and activates microglia to an M1 or mixed M1/M2 state. We show an increased expression of Nos2 and Tnfa and a decreased expression of Chil3 (YM1) from primary cultures of brain microglia exposed to high levels of ATP. Sustained stimulation can reduce lysosomal function in microglia by increasing lysosomal pH and slowing autophagosome-lysosome fusion. P2X7 receptor stimulation can also cause lysosomal leakage, and the subsequent rise in cytoplasmic cathepsin B activates the NLRP3 inflammasome leading to caspase-1 cleavage and IL-1β maturation and release. Support for P2X7 receptor activation of the inflammasome following lysosomal leakage comes from data on primary microglia showing IL-1β release following receptor stimulation is inhibited by cathepsin B blocker CA-074. This pathway bridges endolysosomal and inflammatory roles and may provide a key mechanism for the increased inflammation found in age-dependent neurodegenerations characterized by excessive lysosomal accumulations. Regardless of whether the inflammasome is activated via this lysosomal leakage or the better-known K+-efflux pathway, the inflammatory impact of P2X7 receptor stimulation is balanced between the autophagic reduction of inflammasome components and their increase following P2X7-mediated priming. In summary, the P2X7 receptor modulates clearance of extracellular debris by microglial cells and mediates lysosomal damage that can activate the NLRP3 inflammasome. A better understanding of how the P2X7 receptor alters phagocytosis, lysosomal health, inflammation, and autophagy can lead to therapies that balance the inflammatory and clearance roles of microglial cells.
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Affiliation(s)
- Keith E Campagno
- Department of Basic and Translational Science, University of Pennsylvania, Philadelphia, PA, United States
| | - Claire H Mitchell
- Department of Basic and Translational Science, University of Pennsylvania, Philadelphia, PA, United States.,Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA, United States.,Department of Physiology, University of Pennsylvania, Philadelphia, PA, United States
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Chen TT, Zhou X, Xu YN, Li Y, Wu XY, Xiang Q, Fu LY, Hu XX, Tao L, Shen XC. Gastrodin ameliorates learning and memory impairment in rats with vascular dementia by promoting autophagy flux via inhibition of the Ca 2+/CaMKII signal pathway. Aging (Albany NY) 2021; 13:9542-9565. [PMID: 33714957 PMCID: PMC8064221 DOI: 10.18632/aging.202667] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2020] [Accepted: 11/30/2020] [Indexed: 12/12/2022]
Abstract
Vascular dementia (VD) is a common disease that occurs during human aging. Gastrodin (GAS) has potential benefits for the prevention and treatment of VD. In the present study, we investigated the effects of GAS on cognitive dysfunction in rats with VD induced by permanent middle cerebral artery occlusion (pMCAO) and explored the underlying mechanism. Immunohistochemical and western blot analyses revealed that GAS attenuated hippocampal levels of LC3 (microtubule-associated protein 1 light chain 3), p62, and phosphorylated CaMKII (Ca2+-calmodulin stimulated protein kinase II) in VD rats. Additionally, our results revealed that cobalt chloride blocked autophagic flux in HT22 cells, which was confirmed by increased levels of LC3 and p62 when combined with chloroquine. Notably, GAS ameliorated the impaired autophagic flux. Furthermore, we confirmed that GAS combined with KN93 (a CaMKII inhibitor) or CaMKII knockdown did not impact the reduced p62 levels when compared with GAS treatment alone. Furthermore, a co-immunoprecipitation assay demonstrated that endogenous p62 bound to CaMKII, as confirmed by mass spectrometric analysis after the immunoprecipitation of p62 from HT22 cells. These findings revealed that GAS attenuated autophagic flux dysfunction by inhibiting the Ca2+/CaMKII signaling pathway to ameliorate cognitive impairment in VD.
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Affiliation(s)
- Ting-Ting Chen
- The High Efficacy Application of Natural Medicinal Resources Engineering Center of Guizhou Province and The High Educational Key Laboratory of Guizhou Province for Natural Medicinal Pharmacology and Druggability, School of Pharmaceutical Sciences, Guizhou Medical University, Guiyang 550025, P.R. China.,Guiyang Maternal and Child Health-Care Hospital, Guiyang 550000, P.R. China.,The Key Laboratory of Optimal Utilization of Natural Medicine Resources and The Union Key Laboratory of Guiyang City, Guizhou Medical University, School of Pharmaceutical Sciences, Guiyang 550025, P.R. China
| | - Xue Zhou
- The High Efficacy Application of Natural Medicinal Resources Engineering Center of Guizhou Province and The High Educational Key Laboratory of Guizhou Province for Natural Medicinal Pharmacology and Druggability, School of Pharmaceutical Sciences, Guizhou Medical University, Guiyang 550025, P.R. China
| | - Yi-Ni Xu
- The High Efficacy Application of Natural Medicinal Resources Engineering Center of Guizhou Province and The High Educational Key Laboratory of Guizhou Province for Natural Medicinal Pharmacology and Druggability, School of Pharmaceutical Sciences, Guizhou Medical University, Guiyang 550025, P.R. China
| | - Yue Li
- Guiyang Maternal and Child Health-Care Hospital, Guiyang 550000, P.R. China
| | - Xiao-Ying Wu
- The High Efficacy Application of Natural Medicinal Resources Engineering Center of Guizhou Province and The High Educational Key Laboratory of Guizhou Province for Natural Medicinal Pharmacology and Druggability, School of Pharmaceutical Sciences, Guizhou Medical University, Guiyang 550025, P.R. China.,The Key Laboratory of Optimal Utilization of Natural Medicine Resources and The Union Key Laboratory of Guiyang City, Guizhou Medical University, School of Pharmaceutical Sciences, Guiyang 550025, P.R. China
| | - Quan Xiang
- The High Efficacy Application of Natural Medicinal Resources Engineering Center of Guizhou Province and The High Educational Key Laboratory of Guizhou Province for Natural Medicinal Pharmacology and Druggability, School of Pharmaceutical Sciences, Guizhou Medical University, Guiyang 550025, P.R. China.,The Key Laboratory of Endemic and Ethnic Diseases of Ministry of Education, Guizhou Medical University, Guiyang 550025, P.R. China
| | - Ling-Yun Fu
- The High Efficacy Application of Natural Medicinal Resources Engineering Center of Guizhou Province and The High Educational Key Laboratory of Guizhou Province for Natural Medicinal Pharmacology and Druggability, School of Pharmaceutical Sciences, Guizhou Medical University, Guiyang 550025, P.R. China.,The Key Laboratory of Endemic and Ethnic Diseases of Ministry of Education, Guizhou Medical University, Guiyang 550025, P.R. China
| | - Xiao-Xia Hu
- The High Efficacy Application of Natural Medicinal Resources Engineering Center of Guizhou Province and The High Educational Key Laboratory of Guizhou Province for Natural Medicinal Pharmacology and Druggability, School of Pharmaceutical Sciences, Guizhou Medical University, Guiyang 550025, P.R. China.,The Key Laboratory of Endemic and Ethnic Diseases of Ministry of Education, Guizhou Medical University, Guiyang 550025, P.R. China
| | - Ling Tao
- The High Efficacy Application of Natural Medicinal Resources Engineering Center of Guizhou Province and The High Educational Key Laboratory of Guizhou Province for Natural Medicinal Pharmacology and Druggability, School of Pharmaceutical Sciences, Guizhou Medical University, Guiyang 550025, P.R. China
| | - Xiang-Chun Shen
- The High Efficacy Application of Natural Medicinal Resources Engineering Center of Guizhou Province and The High Educational Key Laboratory of Guizhou Province for Natural Medicinal Pharmacology and Druggability, School of Pharmaceutical Sciences, Guizhou Medical University, Guiyang 550025, P.R. China.,The Key Laboratory of Optimal Utilization of Natural Medicine Resources and The Union Key Laboratory of Guiyang City, Guizhou Medical University, School of Pharmaceutical Sciences, Guiyang 550025, P.R. China.,The Key Laboratory of Endemic and Ethnic Diseases of Ministry of Education, Guizhou Medical University, Guiyang 550025, P.R. China
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Retromer dysfunction at the nexus of tauopathies. Cell Death Differ 2021; 28:884-899. [PMID: 33473181 PMCID: PMC7937680 DOI: 10.1038/s41418-020-00727-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 12/13/2020] [Accepted: 12/27/2020] [Indexed: 01/30/2023] Open
Abstract
Tauopathies define a broad range of neurodegenerative diseases that encompass pathological aggregation of the microtubule-associated protein tau. Although tau aggregation is a central feature of these diseases, their underlying pathobiology is remarkably heterogeneous at the molecular level. In this review, we summarize critical differences that account for this heterogeneity and contrast the physiological and pathological functions of tau. We focus on the recent understanding of its prion-like behavior that accounts for its spread in the brain. Moreover, we acknowledge the limited appreciation about how upstream cellular changes influence tauopathy. Dysfunction of the highly conserved endosomal trafficking complex retromer is found in numerous tauopathies such as Alzheimer's disease, Pick's disease, and progressive supranuclear palsy, and we discuss how this has emerged as a major contributor to various aspects of neurodegenerative diseases. In particular, we highlight recent investigations that have elucidated the contribution of retromer dysfunction to distinct measures of tauopathy such as tau hyperphosphorylation, aggregation, and impaired cognition and behavior. Finally, we discuss the potential benefit of targeting retromer for modifying disease burden and identify important considerations with such an approach moving toward clinical translation.
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49
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Zhou HR, Ma XF, Lin WJ, Hao M, Yu XY, Li HX, Xu CY, Kuang HY. Neuroprotective Role of GLP-1 Analog for Retinal Ganglion Cells via PINK1/Parkin-Mediated Mitophagy in Diabetic Retinopathy. Front Pharmacol 2021; 11:589114. [PMID: 33679385 PMCID: PMC7928389 DOI: 10.3389/fphar.2020.589114] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Accepted: 12/07/2020] [Indexed: 12/23/2022] Open
Abstract
GLP-1 analogs have been widely used to treat patients with type 2 diabetes in recent years and studies have found that GLP-1 analogs have multiple organ benefits. However, the role of GLP-1 analogs in diabetic retinopathy (DR), a common complication of diabetes mellitus (DM), remains controversial. Retinal ganglion cells (RGCs) are the only afferent neurons responsible for transmitting visual information to the visual center and are vulnerable in the early stage of DR. Protection of RGC is vital for visual function. The incretin glucagon-like peptide-1 (GLP-1), which is secreted by L-cells after food ingestion, could lower blood glucose level through stimulating the release of insulin. In the present study, we evaluated the effects of GLP-1 analog on RGCs both in vitro and in vivo. We established diabetic rat models in vivo and applied an RGC-5 cell line in vitro. The results showed that in high glucose conditions, GLP-1 analog alleviated the damage of RGCs. In addition, GLP-1 analog prevented mitophagy through the PINK1/Parkin pathway. Here we demonstrated the neuroprotective effect of GLP-1 analog, which may be beneficial for retinal function, and we further elucidated a novel mechanism in GLP-1 analog-regulated protection of the retina. These findings may expand the multi-organ benefits of GLP-1 analogs and provide new insights for the prevention of DR.
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Affiliation(s)
- Huan-Ran Zhou
- Department of Endocrinology, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Xue-Fei Ma
- Department of Endocrinology, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Wen-Jian Lin
- Department of Endocrinology, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Ming Hao
- Department of Endocrinology, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Xin-Yang Yu
- Department of Endocrinology, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Hong-Xue Li
- Department of Endocrinology, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Cheng-Ye Xu
- Department of Endocrinology, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Hong-Yu Kuang
- Department of Endocrinology, The First Affiliated Hospital of Harbin Medical University, Harbin, China
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50
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Aging and age-related diseases: from mechanisms to therapeutic strategies. Biogerontology 2021; 22:165-187. [PMID: 33502634 PMCID: PMC7838467 DOI: 10.1007/s10522-021-09910-5] [Citation(s) in RCA: 189] [Impact Index Per Article: 63.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Accepted: 01/01/2021] [Indexed: 01/10/2023]
Abstract
Aging is a physiological process mediated by numerous biological and genetic pathways, which are directly linked to lifespan and are a driving force for all age-related diseases. Human life expectancy has greatly increased in the past few decades, but this has not been accompanied by a similar increase in their healthspan. At present, research on aging biology has focused on elucidating the biochemical and genetic pathways that contribute to aging over time. Several aging mechanisms have been identified, primarily including genomic instability, telomere shortening, and cellular senescence. Aging is a driving factor of various age-related diseases, including neurodegenerative diseases, cardiovascular diseases, cancer, immune system disorders, and musculoskeletal disorders. Efforts to find drugs that improve the healthspan by targeting the pathogenesis of aging have now become a hot topic in this field. In the present review, the status of aging research and the development of potential drugs for aging-related diseases, such as metformin, rapamycin, resveratrol, senolytics, as well as caloric restriction, are summarized. The feasibility, side effects, and future potential of these treatments are also discussed, which will provide a basis to develop novel anti-aging therapeutics for improving the healthspan and preventing aging-related diseases.
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