1
|
Yang H, Li J, Li X, Ma L, Hou M, Zhou H, Zhou R. Based on molecular structures: Amyloid-β generation, clearance, toxicity and therapeutic strategies. Front Mol Neurosci 2022; 15:927530. [PMID: 36117918 PMCID: PMC9470852 DOI: 10.3389/fnmol.2022.927530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2022] [Accepted: 07/25/2022] [Indexed: 11/13/2022] Open
Abstract
Amyloid-β (Aβ) has long been considered as one of the most important pathogenic factors in Alzheimer’s disease (AD), but the specific pathogenic mechanism of Aβ is still not completely understood. In recent years, the development of structural biology technology has led to new understandings about Aβ molecular structures, Aβ generation and clearance from the brain and peripheral tissues, and its pathological toxicity. The purpose of the review is to discuss Aβ metabolism and toxicity, and the therapeutic strategy of AD based on the latest progress in molecular structures of Aβ. The Aβ structure at the atomic level has been analyzed, which provides a new and refined perspective to comprehend the role of Aβ in AD and to formulate therapeutic strategies of AD.
Collapse
Affiliation(s)
- Hai Yang
- Department of Neurology, Army Medical Center of PLA, Chongqing, China
| | - Jinping Li
- Department of Neurology, The First Affiliated Hospital of Bengbu Medical College, Bengbu, China
| | - Xiaoxiong Li
- Department of Neurology, The First Affiliated Hospital of Bengbu Medical College, Bengbu, China
| | - Linqiu Ma
- Department of Neurology, The First Affiliated Hospital of Bengbu Medical College, Bengbu, China
| | - Mingliang Hou
- Department of Neurology, The First Affiliated Hospital of Bengbu Medical College, Bengbu, China
| | - Huadong Zhou
- Department of Neurology, Army Medical Center of PLA, Chongqing, China
| | - Rui Zhou
- Southwest Hospital, Army Medical University, Chongqing, China
- *Correspondence: Rui Zhou,
| |
Collapse
|
2
|
Zhang ZW, Tu H, Jiang M, Vanan S, Chia SY, Jang SE, Saw WT, Ong ZW, Ma DR, Zhou ZD, Xu J, Guo KH, Yu WP, Ling SC, Margolin RA, Chain DG, Zeng L, Tan EK. The APP intracellular domain promotes LRRK2 expression to enable feed-forward neurodegenerative mechanisms in Parkinson's disease. Sci Signal 2022; 15:eabk3411. [PMID: 35998231 DOI: 10.1126/scisignal.abk3411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Gain-of-function mutations in the leucine-rich repeat kinase 2 (LRRK2) gene are common in familial forms of Parkinson's disease (PD), which is characterized by progressive neurodegeneration that impairs motor and cognitive function. We previously demonstrated that LRRK2-mediated phosphorylation of β-amyloid precursor protein (APP) triggers the production and nuclear translocation of the APP intracellular domain (AICD). Here, we connected LRRK2 to AICD in a feed-forward cycle that enhanced LRRK2-mediated neurotoxicity. In cooperation with the transcription factor FOXO3a, AICD promoted LRRK2 expression, thus increasing the abundance of LRRK2 that promotes AICD activation. APP deficiency in LRRK2G2019S mice suppressed LRRK2 expression, LRRK2-mediated mitochondrial dysfunction, α-synuclein accumulation, and tyrosine hydroxylase (TH) loss in the brain, phenotypes associated with toxicity and loss of dopaminergic neurons in PD. Conversely, AICD overexpression increased LRRK2 expression and LRRK2-mediated neurotoxicity in LRRK2G2019S mice. In LRRK2G2019S mice or cultured dopaminergic neurons from LRRK2G2019S patients, treatment with itanapraced reduced LRRK2 expression and was neuroprotective. Itanapraced showed similar effects in a neurotoxin-induced PD mouse model, suggesting that inhibiting the AICD may also have therapeutic benefits in idiopathic PD. Our findings reveal a therapeutically targetable, feed-forward mechanism through which AICD promotes LRRK2-mediated neurotoxicity in PD.
Collapse
Affiliation(s)
- Zhi-Wei Zhang
- Neural Stem Cell Research Lab, Research Department, National Neuroscience Institute, Singapore 308433, Singapore
| | - Haitao Tu
- Neural Stem Cell Research Lab, Research Department, National Neuroscience Institute, Singapore 308433, Singapore
| | - Mei Jiang
- Neural Stem Cell Research Lab, Research Department, National Neuroscience Institute, Singapore 308433, Singapore.,Department of Anatomy and Neurobiology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong 510080, China
| | - Sarivin Vanan
- Neural Stem Cell Research Lab, Research Department, National Neuroscience Institute, Singapore 308433, Singapore
| | - Sook Yoong Chia
- Neural Stem Cell Research Lab, Research Department, National Neuroscience Institute, Singapore 308433, Singapore
| | - Se-Eun Jang
- Neural Stem Cell Research Lab, Research Department, National Neuroscience Institute, Singapore 308433, Singapore
| | - Wuan-Ting Saw
- Research Department, National Neuroscience Institute, Singapore General Hospital (SGH) Campus, Singapore 169856, Singapore
| | - Zhi-Wei Ong
- Neural Stem Cell Research Lab, Research Department, National Neuroscience Institute, Singapore 308433, Singapore
| | - Dong-Rui Ma
- Department of Neurology, Singapore General Hospital, Singapore 169609, Singapore
| | - Zhi-Dong Zhou
- Research Department, National Neuroscience Institute, Singapore General Hospital (SGH) Campus, Singapore 169856, Singapore.,Neuroscience and Behavioral Disorders Program, DUKE-NUS Graduate Medical School, Singapore 169857, Singapore
| | - Jie Xu
- Department of Anatomy and Neurobiology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong 510080, China
| | - Kai-Hua Guo
- Department of Anatomy and Neurobiology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong 510080, China
| | - Wei-Ping Yu
- Animal Gene Editing Laboratory, Biological Resource Center, A*STAR, Singapore 138673, Singapore.,Institute of Molecular and Cell Biology, A*STAR, Singapore 138673, Singapore
| | - Shuo-Chien Ling
- Neuroscience and Behavioral Disorders Program, DUKE-NUS Graduate Medical School, Singapore 169857, Singapore.,Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119077, Singapore
| | | | | | - Li Zeng
- Neural Stem Cell Research Lab, Research Department, National Neuroscience Institute, Singapore 308433, Singapore.,Neuroscience and Behavioral Disorders Program, DUKE-NUS Graduate Medical School, Singapore 169857, Singapore.,Centre for Molecular Neuropathology, Lee Kong Chian School of Medicine, Nanyang Technology University, Novena Campus, Singapore 308232, Singapore
| | - Eng-King Tan
- Research Department, National Neuroscience Institute, Singapore General Hospital (SGH) Campus, Singapore 169856, Singapore.,Neuroscience and Behavioral Disorders Program, DUKE-NUS Graduate Medical School, Singapore 169857, Singapore.,Department of Neurology, National Neuroscience Institute, Singapore 308433, Singapore
| |
Collapse
|
3
|
Greenwood EK, Angelova DM, Büchner HMI, Brown DR. The AICD fragment of APP initiates a FoxO3a mediated response via FANCD2. Mol Cell Neurosci 2022; 122:103760. [PMID: 35901928 DOI: 10.1016/j.mcn.2022.103760] [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: 06/10/2022] [Revised: 07/11/2022] [Accepted: 07/21/2022] [Indexed: 11/18/2022] Open
Abstract
The amyloid precursor protein (APP) is a cell surface protein of uncertain function that is notable for being the parent protein of beta-amyloid. Research around this protein has focussed heavily on the link to Alzheimer's disease and neurodegeneration. However, there is increasing evidence that APP may be linked to neuronal loss through mechanisms independent of beta-amyloid. FoxO3a is a transcription factor associated with neuronal longevity and apoptosis. In neurons, FoxO3a is associated with cell death through pathways that include BIM, a BCL-2 family member. In this study we have shown that APP overexpression increased the cellular levels and activity of FoxO3a. This increased expression and activity is not a result of decreased phosphorylation but is more likely a result of increased nuclear stability due to increased levels of FANCD2, a binding partner of FoxO3a. The changes caused by APP overexpression were shown to be due to the AICD fragment of APP possibly directly inducing transcription increase in FANCD2. These findings strengthen the link between APP metabolism and FoxO3a neuronal activity. This link may be crucial in better understanding the cellular role of APP and its link to neurodegeneration and aging.
Collapse
Affiliation(s)
| | | | | | - David R Brown
- Department of Life Sciences, University of Bath, Bath BA2 7AY, UK.
| |
Collapse
|
4
|
D’Andrea L, Stringhi R, Di Luca M, Marcello E. Looking at Alzheimer's Disease Pathogenesis from the Nuclear Side. Biomolecules 2021; 11:biom11091261. [PMID: 34572474 PMCID: PMC8467578 DOI: 10.3390/biom11091261] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 08/19/2021] [Accepted: 08/20/2021] [Indexed: 01/22/2023] Open
Abstract
Alzheimer’s disease (AD) is a neurodegenerative disorder representing the most common form of dementia. It is biologically characterized by the deposition of extracellular amyloid-β (Aβ) senile plaques and intracellular neurofibrillary tangles, constituted by hyperphosphorylated tau protein. The key protein in AD pathogenesis is the amyloid precursor protein (APP), which is cleaved by secretases to produce several metabolites, including Aβ and APP intracellular domain (AICD). The greatest genetic risk factor associated with AD is represented by the Apolipoprotein E ε4 (APOE ε4) allele. Importantly, all of the above-mentioned molecules that are strictly related to AD pathogenesis have also been described as playing roles in the cell nucleus. Accordingly, evidence suggests that nuclear functions are compromised in AD. Furthermore, modulation of transcription maintains cellular homeostasis, and alterations in transcriptomic profiles have been found in neurodegenerative diseases. This report reviews recent advancements in the AD players-mediated gene expression. Aβ, tau, AICD, and APOE ε4 localize in the nucleus and regulate the transcription of several genes, part of which is involved in AD pathogenesis, thus suggesting that targeting nuclear functions might provide new therapeutic tools for the disease.
Collapse
|
5
|
Oli V, Gupta R, Kumar P. FOXO and related transcription factors binding elements in the regulation of neurodegenerative disorders. J Chem Neuroanat 2021; 116:102012. [PMID: 34400291 DOI: 10.1016/j.jchemneu.2021.102012] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2021] [Revised: 07/16/2021] [Accepted: 08/07/2021] [Indexed: 12/16/2022]
Abstract
Neurodegenerative diseases, such as Alzheimer's disease, Parkinson's disease, Huntington's disease, amyotrophic lateral sclerosis, and others, are characterized by progressive loss of neuronal cells, which causes memory impairment and cognitive decline. Mounting evidence demonstrated the possible implications of diverse biological processes, namely oxidative stress, mitochondrial dysfunction, aberrant cell cycle re-entry, post-translational modifications, protein aggregation, impaired proteasome dysfunction, autophagy, and many others that cause neuronal cell death. The condition worsens as there is no effective treatment for such diseases due to their complex pathogenesis and mechanism. Mounting evidence demonstrated the role of regulatory transcription factors, such as NFκβ, FoxO, Myc, CREB, and others that regulate the biological processes and diminish the disease progression and pathogenesis. Studies demonstrated that forkhead box O (FoxO) transcription factors had been implicated in the regulation of aging and longevity. Further, the functions of FoxO proteins are regulated by different post-translational modifications (PTMs), namely acetylation, and ubiquitination. Various studies concluded that FoxO proteins exert both neuroprotective and neurotoxic properties depending on their regulation mechanism and activity in the brain. Thus, understanding the nature of FoxO expression and activity in the brain will help develop effective therapeutic strategies. Herein, firstly, we discuss the role of FoxO protein in cell cycle regulation and cell proliferation, followed by the regulation of FoxO proteins through acetylation and ubiquitination. We also briefly explain the activity and expression pattern of FoxO proteins in the neuronal cells and explain the mechanism through which FoxO proteins are rescued from oxidative stress-induced neurotoxicity. Later on, we present a detailed view of the implication of FoxO proteins in neurodegenerative disease and FoxO proteins as an effective therapeutic target.
Collapse
Affiliation(s)
- Vaibhav Oli
- Molecular Neuroscience and Functional Genomics Laboratory, Delhi Technological University (Formerly Delhi College of Engineering), India
| | - Rohan Gupta
- Molecular Neuroscience and Functional Genomics Laboratory, Delhi Technological University (Formerly Delhi College of Engineering), India
| | - Pravir Kumar
- Molecular Neuroscience and Functional Genomics Laboratory, Delhi Technological University (Formerly Delhi College of Engineering), India.
| |
Collapse
|
6
|
Hole KL, Staniaszek LE, Menon Balan G, Mason JM, Brown JT, Williams RJ. Oral (-)-Epicatechin Inhibits Progressive Tau Pathology in rTg4510 Mice Independent of Direct Actions at GSK3β. Front Neurosci 2021; 15:697319. [PMID: 34220446 PMCID: PMC8244787 DOI: 10.3389/fnins.2021.697319] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Accepted: 05/21/2021] [Indexed: 11/23/2022] Open
Abstract
Aggregation of the microtubule-associated protein tau into paired helical filaments (PHFs) and neurofibrillary tangles is a defining characteristic of Alzheimer’s Disease. Various plant polyphenols disrupt tau aggregation in vitro but display poor bioavailability and low potency, challenging their therapeutic translation. We previously reported that oral administration of the flavonoid (−)-epicatechin (EC) reduced Amyloid-β (Aβ) plaque pathology in APP/PS1 transgenic mice. Here, we investigated whether EC impacts on tau pathology, independent of actions on Aβ, using rTg4510 mice expressing P301L mutant tau. 4 and 6.5 months old rTg4510 mice received EC (∼18 mg/day) or vehicle (ethanol) via drinking water for 21 days and the levels of total and phosphorylated tau were assessed. At 4 months, tau appeared as two bands of ∼55 kDa, phosphorylated at Ser262 and Ser396 and was unaffected by exposure to EC. At 6.5 months an additional higher molecular weight form of tau was detected at ∼64 kDa which was phosphorylated at Ser262, Ser396 and additionally at the AT8 sites, indicative of the presence of PHFs. EC consumption reduced the levels of the ∼64 kDa tau species and inhibited phosphorylation at Ser262 and AT8 phosphoepitopes. Regulation of the key tau kinase glycogen synthase kinase 3β (GSK3β) by phosphorylation at Ser9 was not altered by exposure to EC in mice or primary neurons. Furthermore, EC did not significantly inhibit GSK3β activity at physiologically-relevant concentrations in a cell free assay. Therefore, a 21-day intervention with EC inhibits or reverses the development of tau pathology in rTg4510 mice independently of direct inhibition of GSK3β.
Collapse
Affiliation(s)
- Katriona L Hole
- Department of Biology and Biochemistry, University of Bath, Bath, United Kingdom
| | - Lydia E Staniaszek
- Institute of Biomedical and Clinical Sciences, University of Exeter Medical School, Exeter, United Kingdom
| | - Gayathri Menon Balan
- Department of Biology and Biochemistry, University of Bath, Bath, United Kingdom
| | - Jody M Mason
- Department of Biology and Biochemistry, University of Bath, Bath, United Kingdom
| | - Jon T Brown
- Institute of Biomedical and Clinical Sciences, University of Exeter Medical School, Exeter, United Kingdom
| | - Robert J Williams
- Department of Biology and Biochemistry, University of Bath, Bath, United Kingdom
| |
Collapse
|
7
|
CK1δ-Derived Peptides as Novel Tools Inhibiting the Interactions between CK1δ and APP695 to Modulate the Pathogenic Metabolism of APP. Int J Mol Sci 2021; 22:ijms22126423. [PMID: 34203978 PMCID: PMC8232658 DOI: 10.3390/ijms22126423] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 06/11/2021] [Accepted: 06/11/2021] [Indexed: 12/26/2022] Open
Abstract
Alzheimer’s disease (AD) is the major cause of dementia, and affected individuals suffer from severe cognitive, mental, and functional impairment. Histologically, AD brains are basically characterized by the presence of amyloid plaques and neurofibrillary tangles. Previous reports demonstrated that protein kinase CK1δ influences the metabolism of amyloid precursor protein (APP) by inducing the generation of amyloid-β (Aβ), finally contributing to the formation of amyloid plaques and neuronal cell death. We therefore considered CK1δ as a promising therapeutic target and suggested an innovative strategy for the treatment of AD based on peptide therapeutics specifically modulating the interaction between CK1δ and APP. Initially, CK1δ-derived peptides manipulating the interactions between CK1δ and APP695 were identified by interaction and phosphorylation analysis in vitro. Selected peptides subsequently proved their potential to penetrate cells without inducing cytotoxic effects. Finally, for at least two of the tested CK1δ-derived peptides, a reduction in Aβ levels and amyloid plaque formation could be successfully demonstrated in a complex cell culture model for AD. Consequently, the presented results provide new insights into the interactions of CK1δ and APP695 while also serving as a promising starting point for further development of novel and highly innovative pharmacological tools for the treatment of AD.
Collapse
|
8
|
Jiang M, Vanan S, Tu HT, Zhang W, Zhang ZW, Chia SY, Jang SE, Zeng XX, Yu WP, Xu J, Guo KH, Zeng L. Amyloid precursor protein intracellular domain-dependent regulation of FOXO3a inhibits adult hippocampal neurogenesis. Neurobiol Aging 2020; 95:250-263. [PMID: 32866886 DOI: 10.1016/j.neurobiolaging.2020.07.031] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Revised: 07/14/2020] [Accepted: 07/29/2020] [Indexed: 10/23/2022]
Abstract
The amyloid precursor protein (APP) intracellular domain (AICD) is a metabolic by-product of APP produced through sequential proteolytic cleavage by α-, β-, and γ-secretases. The interaction between AICD and Fe65 has been reported to impair adult neurogenesis in vivo. However, the exact role of AICD in mediating neural stem cell fate remains unclear. To identify the role of AICD in neuronal proliferation and differentiation, as well as to clarify the molecular mechanisms underlying the role of AICD in neurogenesis, we first generated a mouse model expressing the Rosa26-based AICD transgene. AICD overexpression did not alter the spatiotemporal expression pattern of full-length APP or accumulation of its metabolites. In addition, AICD decreased the newly generated neural progenitor cell (NPC) pool, inhibited the proliferation and differentiation efficiency of NPCs, and increased cell death both in vitro and in vivo. Given that abnormal neurogenesis is often associated with depression-like behavior in adult mice, we conducted a forced swim test and tail suspension test with AICD mice and found a depression-like behavioral phenotype in AICD transgenic mice. Moreover, AICD stimulated FOXO3a transcriptional activation, which in turn negatively regulated AICD. In addition, functional loss of FOXO3a in NPCs derived from the hippocampal dentate gyrus of adult AICD transgenic mice rescued neurogenesis defects. AICD also increased the mRNA expression of FOXO3a target genes related to neurogenesis and cell death. These results suggest that FOXO3a is the functional target of AICD in neurogenesis regulation. Our study reveals the role of AICD in mediating neural stem cell fate to maintain homeostasis during brain development via interaction with FOXO3a.
Collapse
Affiliation(s)
- Mei Jiang
- Department of Neurobiology and Anatomy, Sun Yat-Sen University Zhongshan School of Medicine, Guangzhou, PR China; Neural Stem Cell Research Lab, Research Department, National Neuroscience Institute, Singapore
| | - Sarivin Vanan
- Neural Stem Cell Research Lab, Research Department, National Neuroscience Institute, Singapore
| | - Hai-Tao Tu
- Neural Stem Cell Research Lab, Research Department, National Neuroscience Institute, Singapore
| | - Wei Zhang
- Neural Stem Cell Research Lab, Research Department, National Neuroscience Institute, Singapore
| | - Zhi-Wei Zhang
- Neural Stem Cell Research Lab, Research Department, National Neuroscience Institute, Singapore
| | - Sook-Yoong Chia
- Neural Stem Cell Research Lab, Research Department, National Neuroscience Institute, Singapore
| | - Se Eun Jang
- Neural Stem Cell Research Lab, Research Department, National Neuroscience Institute, Singapore
| | - Xiao-Xia Zeng
- Neural Stem Cell Research Lab, Research Department, National Neuroscience Institute, Singapore
| | - Wei-Ping Yu
- Animal Gene Editing Laboratory, Biological resource Centre, A∗STAR, Singapore; Institute of Molecular and Cell Biology, A∗STAR, Proteos, Singapore
| | - Jie Xu
- Department of Neurobiology and Anatomy, Sun Yat-Sen University Zhongshan School of Medicine, Guangzhou, PR China.
| | - Kai-Hua Guo
- Department of Neurobiology and Anatomy, Sun Yat-Sen University Zhongshan School of Medicine, Guangzhou, PR China.
| | - Li Zeng
- Neural Stem Cell Research Lab, Research Department, National Neuroscience Institute, Singapore; Neuroscience and Behavioral Disorders Program, DUKE-NUS Graduate Medical School, Singapore; Lee Kong Chian School of Medicine, Nanyang Technology University, Novena Campus, Singapore.
| |
Collapse
|
9
|
Chau DDL, Yung KWY, Chan WWL, An Y, Hao Y, Chan HYE, Ngo JCK, Lau KF. Attenuation of amyloid-β generation by atypical protein kinase C-mediated phosphorylation of engulfment adaptor PTB domain containing 1 threonine 35. FASEB J 2019; 33:12019-12035. [PMID: 31373844 DOI: 10.1096/fj.201802825rr] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Amyloid-β (Aβ) is derived from the proteolytic processing of amyloid precursor protein (APP), and the deposition of extracellular Aβ to form amyloid plaques is a pathologic hallmark of Alzheimer's disease (AD). Although reducing Aβ generation and accumulation has been proposed as a means of treating the disease, adverse side effects and unsatisfactory efficacy have been reported in several clinical trials that sought to lower Aβ levels. Engulfment adaptor phosphotyrosine-binding (PTB) domain containing 1 (GULP1) is a molecular adaptor that has been shown to interact with APP to alter Aβ production. Therefore, the modulation of the GULP1-APP interaction may be an alternative approach to reducing Aβ. However, the mechanisms that regulate GULP1-APP binding remain elusive. As GULP1 is a phosphoprotein, and because phosphorylation is a common mechanism that regulates protein interaction, we anticipated that GULP1 phosphorylation would influence GULP1-APP interaction and thereby Aβ production. We show here that the phosphorylation of GULP1 threonine 35 (T35) reduces GULP1-APP interaction and suppresses the stimulatory effect of GULP1 on APP processing. The residue is phosphorylated by an isoform of atypical PKC (PKCζ). Overexpression of PKCζ reduces both GULP1-APP interaction and GULP1-mediated Aβ generation. Moreover, the activation of PKCζ via insulin suppresses APP processing. In contrast, GULP1-mediated APP processing is enhanced in PKCζ knockout cells. Similarly, PKC ι, another member of atypical PKC, also decreases GULP1-mediated APP processing. Intriguingly, our X-ray crystal structure of GULP1 PTB-APP intracellular domain (AICD) peptide reveals that GULP1 T35 is not located at the GULP1-AICD binding interface; rather, it immediately precedes the β1-α2 loop that forms a portion of the binding groove for the APP helix αC. Phosphorylating the residue may induce an allosteric effect on the conformation of the binding groove. Our results indicate that GULP1 T35 phosphorylation is a mechanism for the regulation of GULP1-APP interaction and thereby APP processing. Moreover, the activation of atypical PKC, such as by insulin, may confer a beneficial effect on AD by lowering GULP1-mediated Aβ production.-Chau, D. D.-L., Yung, K. W.-Y., Chan, W. W.-L., An, Y., Hao, Y., Chan, H.-Y. E., Ngo, J. C.-K., Lau, K.-F. Attenuation of amyloid-β generation by atypical protein kinase C-mediated phosphorylation of engulfment adaptor PTB domain containing 1 threonine 35.
Collapse
Affiliation(s)
- Dennis Dik-Long Chau
- Faculty of Science, School of Life Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Kristen Wing-Yu Yung
- Faculty of Science, School of Life Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - William Wai-Lun Chan
- Faculty of Science, School of Life Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Ying An
- Faculty of Science, School of Life Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Yan Hao
- Faculty of Science, School of Life Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Ho-Yin Edwin Chan
- Faculty of Science, School of Life Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Jacky Chi-Ki Ngo
- Faculty of Science, School of Life Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Kwok-Fai Lau
- Faculty of Science, School of Life Sciences, The Chinese University of Hong Kong, Hong Kong, China
| |
Collapse
|
10
|
Kamikubo Y, Yamana T, Hashimoto Y, Sakurai T. Induction of Oxidative Stress and Cell Death in Neural Cells by Silica Nanoparticles. ACS Chem Neurosci 2019; 10:304-312. [PMID: 30230808 DOI: 10.1021/acschemneuro.8b00248] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Silica nanoparticles (SiNPs) are produced on an industrial scale and used in various fields including health care, because silica is stable, inexpensive, and easy to handle. Despite these benefits, there is concern that exposure to SiNPs may lead to adverse effects in certain types of cells or tissues, such as hemolysis, immune responses, and developmental abnormalities in the brain and developing embryos. Although investigations on the toxicity of SiNPs against neurons are essential for medicinal use, only a few studies have assessed the direct effects of SiNPs on cells derived from the central nervous system. In this study, we investigated the toxic effects of SiNPs on primary cultures of hippocampal cells, using SiNPs with diameters of 10-1500 nm. We showed that treatment with SiNPs caused oxidative stress and cell death. Furthermore, we found that these cytotoxicities were dependent on the particle size, concentration, and surface charge of SiNPs, as well as the treatment temperature. The toxicity was reduced by SiNP surface functionalization or protein coating and by pretreating cells with an antioxidant, suggesting that contact-induced oxidative stress may be partially responsible for SiNP-induced cell death. These data will be valuable for utilizing SiNPs in biomedical applications.
Collapse
Affiliation(s)
- Yuji Kamikubo
- Department of Pharmacology, Juntendo University School of Medicine, Hongo 2-1-1, Bunkyo-ku, Tokyo 113-8421, Japan
| | - Tomohito Yamana
- Department of Pharmacology, Juntendo University School of Medicine, Hongo 2-1-1, Bunkyo-ku, Tokyo 113-8421, Japan
| | - Yoshie Hashimoto
- Department of Pharmacology, Juntendo University School of Medicine, Hongo 2-1-1, Bunkyo-ku, Tokyo 113-8421, Japan
| | - Takashi Sakurai
- Department of Pharmacology, Juntendo University School of Medicine, Hongo 2-1-1, Bunkyo-ku, Tokyo 113-8421, Japan
| |
Collapse
|
11
|
Batkulwar K, Godbole R, Banarjee R, Kassaar O, Williams RJ, Kulkarni MJ. Advanced Glycation End Products Modulate Amyloidogenic APP Processing and Tau Phosphorylation: A Mechanistic Link between Glycation and the Development of Alzheimer's Disease. ACS Chem Neurosci 2018; 9:988-1000. [PMID: 29384651 DOI: 10.1021/acschemneuro.7b00410] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Advanced glycation end products (AGEs) are implicated in the pathology of Alzheimer's disease (AD), as they induce neurodegeneration following interaction with the receptor for AGE (RAGE). This study aimed to establish a mechanistic link between AGE-RAGE signaling and AD pathology. AGE-induced changes in the neuro2a proteome were monitored by SWATH-MS. Western blotting and cell-based reporter assays were used to investigate AGE-RAGE regulated APP processing and tau phosphorylation in primary cortical neurons. Selected protein expression was validated in brain samples affected by AD. The AGE-RAGE axis altered proteome included increased expression of cathepsin B and asparagine endopeptidase (AEP), which mediated an increase in Aβ1-42 formation and tau phosphorylation, respectively. Elevated cathepsin B, AEP, RAGE, and pTau levels were found in human AD brain, coincident with enhanced AGEs. This study demonstrates that the AGE-RAGE axis regulates Aβ1-42 formation and tau phosphorylation via increased cathepsin B and AEP, providing a new molecular link between AGEs and AD pathology.
Collapse
Affiliation(s)
- Kedar Batkulwar
- Proteomics Facility, Division of Biochemical Sciences, CSIR-National Chemical Laboratory, Pune-411008, India
- Academy of Scientific and Innovative Research (AcSIR), CSIR-National Chemical Laboratory, Pune-411008, India
| | - Rashmi Godbole
- Proteomics Facility, Division of Biochemical Sciences, CSIR-National Chemical Laboratory, Pune-411008, India
| | - Reema Banarjee
- Proteomics Facility, Division of Biochemical Sciences, CSIR-National Chemical Laboratory, Pune-411008, India
- Academy of Scientific and Innovative Research (AcSIR), CSIR-National Chemical Laboratory, Pune-411008, India
| | - Omar Kassaar
- Department of Biology and Biochemistry, University of Bath, Bath BA2 7AY, U.K
| | - Robert J. Williams
- Department of Biology and Biochemistry, University of Bath, Bath BA2 7AY, U.K
| | - Mahesh J. Kulkarni
- Proteomics Facility, Division of Biochemical Sciences, CSIR-National Chemical Laboratory, Pune-411008, India
- Academy of Scientific and Innovative Research (AcSIR), CSIR-National Chemical Laboratory, Pune-411008, India
| |
Collapse
|