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Sosa LJ, Cáceres A, Dupraz S, Oksdath M, Quiroga S, Lorenzo A. The physiological role of the amyloid precursor protein as an adhesion molecule in the developing nervous system. J Neurochem 2017; 143:11-29. [PMID: 28677143 DOI: 10.1111/jnc.14122] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Revised: 06/28/2017] [Accepted: 06/29/2017] [Indexed: 12/12/2022]
Abstract
The amyloid precursor protein (APP) is a type I transmembrane glycoprotein better known for its participation in the physiopathology of Alzheimer disease as the source of the beta amyloid fragment. However, the physiological functions of the full length protein and its proteolytic fragments have remained elusive. APP was first described as a cell-surface receptor; nevertheless, increasing evidence highlighted APP as a cell adhesion molecule. In this review, we will focus on the current knowledge of the physiological role of APP as a cell adhesion molecule and its involvement in key events of neuronal development, such as migration, neurite outgrowth, growth cone pathfinding, and synaptogenesis. Finally, since APP is over-expressed in Down syndrome individuals because of the extra copy of chromosome 21, in the last section of the review, we discuss the potential contribution of APP to the neuronal and synaptic defects described in this genetic condition. Read the Editorial Highlight for this article on page 9. Cover Image for this issue: doi. 10.1111/jnc.13817.
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Affiliation(s)
- Lucas J Sosa
- Departamento de Química Biológica Ranwell Caputto, Facultad de Ciencias Químicas, CIQUIBIC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Alfredo Cáceres
- Laboratorio Neurobiología, Instituto Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina.,Instituto Universitario Ciencias Biomédicas Córdoba, Córdoba, Argentina
| | - Sebastián Dupraz
- Axonal Growth and Regeneration, German Center for Neurodegenarative Diseases, Bonn, Germany
| | - Mariana Oksdath
- Departamento de Química Biológica Ranwell Caputto, Facultad de Ciencias Químicas, CIQUIBIC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Santiago Quiroga
- Departamento de Química Biológica Ranwell Caputto, Facultad de Ciencias Químicas, CIQUIBIC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Alfredo Lorenzo
- Laboratorio de Neuropatología Experimental, Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
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Alpár A, Ueberham U, Lendvai D, Naumann N, Rohn S, Gáti G, Arendt T, Gärtner U. Activity-induced dendrite and dendritic spine development in human amyloid precursor protein transgenic mice. Int J Dev Neurosci 2011; 29:107-14. [PMID: 21277971 DOI: 10.1016/j.ijdevneu.2011.01.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2010] [Revised: 12/29/2010] [Accepted: 01/10/2011] [Indexed: 10/18/2022] Open
Abstract
The amyloid precursor protein is essential for proper neuronal function but an imbalance in processing or metabolism or its overexpression lead to severe malfunction of the brain. The present study focused on dendritic morphology of hippocampal neurons in mice overexpressing the wild-type human amyloid precursor protein (hAPP). In addition, we examined whether enhanced physical activity may affect hAPP-related morphological changes. Overexpression of hAPP resulted in significant enlargement of dendrites, especially within the basal dendritic field but had no effect on spine density. Enhanced physical activity only moderately potentiated hAPP induced changes in dendritic size. Physical activity dependent increases in spine density were, however, augmented by hAPP overexpression. The results suggest that enhanced levels of wild-type hAPP do not result in degenerative changes of neuronal morphology, but rather promote dendritic growth.
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Affiliation(s)
- Alán Alpár
- Department of Anatomy, Histology and Embryology, Semmelweis University Medical School, Tűzoltó u. 58, H-1450 Budapest, Hungary.
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Klaver DW, Wilce MC, Cui H, Hung AC, Gasperini R, Foa L, Small DH. Is BACE1 a suitable therapeutic target for the treatment of Alzheimer's disease? Current strategies and future directions. Biol Chem 2010; 391:849-59. [DOI: 10.1515/bc.2010.089] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Abstract
Alzheimer's disease (AD) is characterized by the extracellular deposition of the β-amyloid protein (Aβ). Aβ is a fragment of a much larger precursor protein, the amyloid precursor protein (APP). Sequential proteolytic cleavage of APP by β-secretase and γ-secretase liberates Aβ from APP. The aspartyl protease BACE1 (β-site APP-cleaving enzyme 1) catalyses the rate-limiting step in the production of Aβ, and as such it is considered to be a major target for drug development in Alzheimer's disease. However, the development of a BACE1 inhibitor therapy is problematic for two reasons. First, BACE1 has been found to have important physiological roles. Therefore, inhibition of the enzyme could have toxic consequences. Second, the active site of BACE1 is relatively large, and many of the bulky compounds that are needed to inhibit BACE1 activity are unlikely to cross the blood-brain barrier. This review focuses on the structure BACE1, current therapeutic strategies based on developing active-site inhibitors, and new approaches to therapy involving targeting the expression or post-translational regulation of BACE1.
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Noristani HN, Olabarria M, Verkhratsky A, Rodríguez JJ. Serotonin fibre sprouting and increase in serotonin transporter immunoreactivity in the CA1 area of hippocampus in a triple transgenic mouse model of Alzheimer's disease. Eur J Neurosci 2010; 32:71-9. [PMID: 20576032 DOI: 10.1111/j.1460-9568.2010.07274.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Alzheimer's disease (AD) is a neurodegenerative disease that deteriorates cognitive functions and associated brain regions such as the hippocampus, being the primary cause of dementia. Serotonin (5-HT) is widely present in the hippocampus, being an important neurotransmitter involved in learning and memory. Although recent evidence suggests alterations in 5-HT neurotransmission in AD, it is not clear how hippocampal 5-HT innervation is modified. Here, we studied hippocampal 5-HT innervation by analysing: (i) the expression, density and distribution of 5-HT transporter (SERT)-immunoreactive fibres; (ii) the specific morphological characteristics of serotonergic fibres and their relation to amyloid plaques; and (iii) the total number of 5-HT neurons within the raphe nuclei in triple transgenic mouse model of AD. We used quantitative light microscopy immunohistochemistry comparing transgenic and non-transgenic animals of different ages (3, 6, 9, 12 and 18 months). The transgenic animals showed a significant increase in SERT fibres in the hippocampus in a subfield-, strata- and age-specific manner. The increase in SERT fibres was specific to the CA1 stratum lacunosum-moleculare. An increase in SERT fibres in transgenic animals was observed at 3 months (by 61%) and at 18 months (by 74%). No changes, however, were found in the total number of raphe 5-HT neurons at any age. Our results indicate that triple transgenic mice display changes in the expression of SERT and increased SERT fibres sprouting, which may account for imbalanced serotonergic neurotransmission associated with (or linked to) AD cognitive impairment.
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Affiliation(s)
- H N Noristani
- Faculty of Life Sciences, The University of Manchester, Manchester, UK
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Fan X, Liu Y, Jiang J, Ma Z, Wu H, Liu T, Liu M, Li X, Tang H. miR-20a promotes proliferation and invasion by targeting APP in human ovarian cancer cells. Acta Biochim Biophys Sin (Shanghai) 2010; 42:318-24. [PMID: 20458444 DOI: 10.1093/abbs/gmq026] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
MicroRNAs (miRNAs) are emerging as a class of small regulated RNAs, and the alterations of miRNAs are implicated in the initiation and progression of human cancers. Our study shows that inhibition of miR-20a in OVCAR3 ovarian cancer cell line could suppress, whereas overexpression of miR-20a could enhance cell long-term proliferation and invasion. We also confirmed amyloid precursor protein (APP) as a direct target gene of miR- 20a. Furthermore, suppression of APP expression could also promote ovarian cancer cell proliferation and invasion, which is consistent with the results of miR-20a overexpression. Therefore, we concluded that the regulation of APP is an important mechanism for miR-20a to promote proliferation and invasion in ovarian cancer cells.
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Affiliation(s)
- Xingxing Fan
- Tianjin Life Science Research Center and Basic Medical School, Tianjin Medical University, Tianjin 300070, China
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Kotulska K, Larysz-Brysz M, LePecheur M, Marcol W, Lewin-Kowalik J, Paly E, London J. APP overexpression prevents neuropathic pain and motoneuron death after peripheral nerve injury in mice. Brain Res Bull 2010; 81:378-84. [DOI: 10.1016/j.brainresbull.2009.10.023] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2009] [Revised: 08/18/2009] [Accepted: 10/12/2009] [Indexed: 11/17/2022]
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Alpár A, Naumann N, Ueberham U, Arendt T, Gärtner U. Deprivation-induced dendritic shrinkage might be oppositely affected by the expression of wild-type and mutated human amyloid precursor protein. J Neurosci Res 2009; 87:1813-22. [PMID: 19170186 DOI: 10.1002/jnr.22008] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The physiological role of the amyloid precursor protein (APP) and its proteolytic fragments in the brain is associated with neuronal survival, neurite outgrowth, synaptic formation, and neuronal plasticity. However, malregulation of APP processing leads to disordered balance of fragments, which may results in opposite, degenerative neuronal effects. In the present study, we analyzed in vivo effects of the expression of wild-type or mutated human APP on afferent deprivation-induced changes of dendritic morphology. After vibrissectomy, expression of wild-type human APP prevented diameter shrinkage of dendritic segments as well as dendritic rarefaction of apical arbors. In contrast, mutant human APP expression exacerbated degenerative changes of deprived barrel neurons. Degradation of apical arbors was especially pronounced. Results demonstrate for the first time opposite effects of the expression of wild-type and mutated human APP on deprivation-induced dendritic restructuring in vivo.
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Affiliation(s)
- Alán Alpár
- Department of Anatomy, Histology and Embryology, Semmelweis University Medical School, Budapest, Hungary.
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Sugaya K. Mechanism of glial differentiation of neural progenitor cells by amyloid precursor protein. NEURODEGENER DIS 2008; 5:170-2. [PMID: 18322381 DOI: 10.1159/000113693] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND We found that human neural progenitor cells (HNPCs) exposed to high concentrations of amyloid precursor protein (APP) or transplanted into APP transgenic mice (APP23) primarily differentiated into astrocytes, suggesting that pathological alterations of APP processing in Alzheimer's disease (AD) may prevent neuronal differentiation of HNPCs. OBJECTIVES To investigate the mechanism of APP-induced glial differentiation of HNPCs. METHODS We treat HNPCs with APP and analyze the expression and phosphorylation of signaling molecules using PCR and Western blots. To confirm the involvement of the factors, RNA interference of the signaling molecule is conducted. RESULTS APP treatment caused inductions of CNTF, gp130 and JAK1 gene expressions, and STAT3 phosphorylation, while silencing of these genes by RNA interference suppressed the glial differentiation of the cells, indicating involvement of the IL-6/gp130 pathway. APP also increased the generation of notch intracellular domain and gene expression of Hes1, indicating that glial differentiation of HNPCs may be mediated by the notch signaling. CONCLUSION These results indicate that APP may regulate HNPC differentiation through activation of both the IL-6/gp130 and notch signaling pathway. Although the importance of adult neurogenesis is not clear, glial differentiation of HNPCs may cause problems in maintaining normal brain function and may contribute to the AD pathology.
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Affiliation(s)
- Kiminobu Sugaya
- Burnett College of Biomedical Sciences, University of Central Florida, Orlando, Fla. 32816-2364, USA.
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Marutle A, Ohmitsu M, Nilbratt M, Greig NH, Nordberg A, Sugaya K. Modulation of human neural stem cell differentiation in Alzheimer (APP23) transgenic mice by phenserine. Proc Natl Acad Sci U S A 2007; 104:12506-11. [PMID: 17640880 PMCID: PMC1941499 DOI: 10.1073/pnas.0705346104] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In a previous study, we found that human neural stem cells (HNSCs) exposed to high concentrations of secreted amyloid-precursor protein (sAPP) in vitro differentiated into mainly astrocytes, suggesting that pathological alterations in APP processing during neurodegenerative conditions such as Alzheimer's disease (AD) may prevent neuronal differentiation of HNSCs. Thus, successful neuroplacement therapy for AD may require regulating APP expression to favorable levels to enhance neuronal differentiation of HNSCs. Phenserine, a recently developed cholinesterase inhibitor (ChEI), has been reported to reduce APP levels in vitro and in vivo. In this study, we found reductions of APP and glial fibrillary acidic protein (GFAP) levels in the hippocampus of APP23 mice after 14 days treatment with (+)-phenserine (25 mg/kg) lacking ChEI activity. No significant change in APP gene expression was detected, suggesting that (+)-phenserine decreases APP levels and reactive astrocytes by posttranscription regulation. HNSCs transplanted into (+)-phenserine-treated APP23 mice followed by an additional 7 days of treatment with (+)-phenserine migrated and differentiated into neurons in the hippocampus and cortex after 6 weeks. Moreover, (+)-phenserine significantly increased neuronal differentiation of implanted HNSCs in hippocampal and cortical regions of APP23 mice and in the CA1 region of control mice. These results indicate that (+)-phenserine reduces APP protein in vivo and increases neuronal differentiation of HNSCs. Combination use of HNSC transplantation and treatment with drugs such as (+)-phenserine that modulate APP levels in the brain may be a useful tool for understanding mechanisms regulating stem cell migration and differentiation during neurodegenerative conditions in AD.
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Affiliation(s)
- Amelia Marutle
- Biomolecular Sciences Center, Burnett College of Biomedical Sciences, University of Central Florida, Orlando, FL 32816, USA.
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Purushothaman A, Fukuda J, Mizumoto S, ten Dam GB, van Kuppevelt TH, Kitagawa H, Mikami T, Sugahara K. Functions of Chondroitin Sulfate/Dermatan Sulfate Chains in Brain Development. J Biol Chem 2007; 282:19442-52. [PMID: 17500059 DOI: 10.1074/jbc.m700630200] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Chondroitin sulfate (CS) and dermatan sulfate (DS) have been implicated in the processes of neural development in the brain. In this study, we characterized developmentally regulated brain CS/DS chains using a single chain antibody, GD3G7, produced by the phage display technique. Evaluation of the specificity of GD3G7 toward various glycosaminoglycan preparations showed that this antibody specifically reacted with squid CS-E (rich in the GlcUAbeta1-3GalNAc(4,6-O-sulfate) disaccharide unit E), hagfish CS-H (rich in the IdoUAalpha1-3GalNAc(4,6-O-sulfate) unit iE), and shark skin DS (rich in both E and iE units). In situ hybridization for the expression of N-acetylgalac-tosamine-4-sulfate 6-O-sulfotransferase in the postnatal mouse brain, which is involved in the biosynthesis of CS/DS-E, showed a widespread expression of the transcript in the developing brain except at postnatal day 7, where strong expression was observed in the external granule cell layer in the cerebellum. The expression switched from the external to internal granule cell layer with development. Immunohistochemical localization of GD3G7 in the mouse brain showed that the epitope was relatively abundant in the cerebellum, hippocampus, and olfactory bulb. GD3G7 suppressed the growth of neurites in embryonic hippocampal neurons mediated by CS-E, suggesting that the epitope is embedded in the neurite outgrowth-promoting motif of CS-E. In addition, a CS-E decasaccharide fraction was found to be the critical minimal structure needed for recognition by GD3G7. Four discrete decasaccharide epitopic sequences were identified. The antibody GD3G7 has broad applications in investigations of CS/DS chains during the central nervous system's development and under various pathological conditions.
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Affiliation(s)
- Anurag Purushothaman
- Department of Biochemistry, Kobe Pharmaceutical University, Higashinada-ku, Kobe 658-8558, Japan
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Regeneration and Repair. Dev Neurobiol 2006. [DOI: 10.1007/0-387-28117-7_12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Rauch U, Kappler J. Chondroitin/Dermatan Sulfates in the Central Nervous System: Their Structures and Functions in Health and Disease. CHONDROITIN SULFATE: STRUCTURE, ROLE AND PHARMACOLOGICAL ACTIVITY 2006; 53:337-56. [PMID: 17239774 DOI: 10.1016/s1054-3589(05)53016-3] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Affiliation(s)
- Uwe Rauch
- Department of Experimental Pathology, Universitet Lund, Lund, Sweden
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Alpár A, Ueberham U, Brückner MK, Arendt T, Gärtner U. The expression of wild-type human amyloid precursor protein affects the dendritic phenotype of neocortical pyramidal neurons in transgenic mice. Int J Dev Neurosci 2005; 24:133-40. [PMID: 16384682 DOI: 10.1016/j.ijdevneu.2005.11.008] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2005] [Accepted: 11/10/2005] [Indexed: 11/27/2022] Open
Abstract
The current study addresses the morphoregulatory effects of human amyloid precursor protein expression on neocortical pyramidal cells in vivo. For this purpose, a transgenic mouse line was used that expresses wild-type human amyloid precursor protein (APP) at levels similar to endogenous mouse APP. This strain does not develop Alzheimer's disease-related pathology which allowed to study effects of APP or APP cleavage products but excluded the influence of amyloid deposits. Commissural projecting pyramidal neurons of layers II/III within the primary somatosensory cortex were retrogradely labelled by injection of biotinylated dextran amine into the corpus callosum. In transgenic mice, computer-aided morphometric analysis revealed an increase in the surface area of proximal and intermediate basal dendritic segments resulting from an enlarged diameter. On the other hand, the length of the same segments was reduced. Both basal and apical dendrites were characterized by a higher dendritic density within the proximal and intermediate fields. Although the total spatial extension of basal and apical dendrites remained unchanged, a moderate withdrawal of arbors is suggested. The results implicate a physiological function for APP in regulatory mechanisms of neuronal morphogenesis.
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Affiliation(s)
- Alán Alpár
- Department of Anatomy, Histology and Embryology, Semmelweis University Medical School, Tuzoltó u. 58, H-1450 Budapest, Hungary
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Li Y, Liu T, Peng Y, Yuan C, Guo A. Specific functions of Drosophila amyloid precursor-like protein in the development of nervous system and nonneural tissues. ACTA ACUST UNITED AC 2005; 61:343-58. [PMID: 15389603 DOI: 10.1002/neu.20048] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Drosophila amyloid precursor-like protein (APPL) is expressed extensively in the nervous system soon after neuronal differentiation. By utilizing different transgenic flies, we studied the physiological function of two APPL protein forms, membrane-bound form (mAPPL) and secreted form (sAPPL), in neural development. We found that neither deletion nor overexpression of APPL protein altered the gross structure of mushroom bodies in the adult brain. No changes were detected in cell types and their relative ration in embryo-derived cultures from all APPL mutants. However, the neurite length was significantly increased in mutants overexpressing mAPPL. In addition, mutants lacking sAPPL had numerous neurite branches with abnormal lamellate membrane structures (LMSs) and blebs, while no apoptosis was detected in these neurons. The abnormal neurite morphology was most likely due to the disorganization of the cytoskeleton, as shown by double staining of actin filaments and microtubules. Electrophysiologically, A-type K+ current was significantly enhanced, and spontaneous excitatory postsynaptic potentials (sEPSPs) were greatly increased in APPL mutants lacking sAPPL. Moreover, panneural overexpression of different forms of APPL protein generated different defects of wings and cuticle in adult flies. Taken together, our results suggest that both mAPPL and sAPPL play essential roles in the development of the central nervous system and nonneural tissues.
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Affiliation(s)
- Yan Li
- Laboratory of Visual Information Processing, Center for Brain and Cognitive Sciences, Institute of Biophysics, Chinese Academy of Sciences, ChaoYang Dist., 15 DaTun Rd, Beijing 100101, People's Republic of China
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King GD, Scott Turner R. Adaptor protein interactions: modulators of amyloid precursor protein metabolism and Alzheimer's disease risk? Exp Neurol 2004; 185:208-19. [PMID: 14736502 DOI: 10.1016/j.expneurol.2003.10.011] [Citation(s) in RCA: 124] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The cytoplasmic C-terminus of APP plays critical roles in its cellular trafficking and delivery to proteases. Adaptor proteins with phosphotyrosine-binding (PTB) domains, including those in the X11, Fe65, and c-Jun N-terminal kinase (JNK)-interacting protein (JIP) families, bind specifically to the absolutely conserved -YENPTY- motif in the APP C-terminus to regulate its trafficking and processing. Compounds that modulate APP-adaptor protein interactions may inhibit Abeta generation by specifically targeting the substrate (APP) instead of the enzyme (beta- or gamma-secretase). Genetic polymorphisms in (or near) adaptor proteins may influence risk of sporadic AD by interacting with APP in vivo to modulate its trafficking and processing to Abeta.
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Affiliation(s)
- Gwendalyn D King
- Neuroscience Program, University of Michigan, Ann Arbor, MI 48105, USA
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Umehara Y, Yamada S, Nishimura S, Shioi J, Robakis NK, Sugahara K. Chondroitin sulfate of appican, the proteoglycan form of amyloid precursor protein, produced by C6 glioma cells interacts with heparin-binding neuroregulatory factors. FEBS Lett 2003; 557:233-8. [PMID: 14741373 DOI: 10.1016/s0014-5793(03)01506-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Appican produced by rat C6 glioma cells, the chondroitin sulfate (CS) proteoglycan form of the amyloid precursor protein, contains an E disaccharide, -GlcUA-GalNAc(4,6-O-disulfate)-, in its CS chain. In this study, the appican CS chain from rat C6 glioma cells was shown to specifically bind several growth/differentiation factors including midkine (MK) and pleiotrophin (PTN). In contrast, the appican CS from SH-SY5Y neuroblastoma cells contained no E disaccharide and showed no binding to either MK or PTN. These findings indicate that the E motif is essential in the interaction of the appican CS chain with growth/differentiation factors, and suggest that glial appican may mediate the regulation of neuronal cell adhesion and migration and/or neurite outgrowth.
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Affiliation(s)
- Yuko Umehara
- Department of Biochemistry, Kobe Pharmaceutical University, 4-19-1 Motoyamakita-machi, Higashinada-ku, Kobe 658-8558, Japan
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Hikino M, Mikami T, Faissner A, Vilela-Silva ACES, Pavão MSG, Sugahara K. Oversulfated dermatan sulfate exhibits neurite outgrowth-promoting activity toward embryonic mouse hippocampal neurons: implications of dermatan sulfate in neuritogenesis in the brain. J Biol Chem 2003; 278:43744-54. [PMID: 12917413 DOI: 10.1074/jbc.m308169200] [Citation(s) in RCA: 104] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Brain-specific chondroitin sulfate (CS) proteoglycan (PG) DSD-1-PG/6B4-PG/phosphacan isolated from neonatal mouse brains exhibits neurite outgrowth-promoting activity toward embryonic rat and mouse hippocampal neurons in vitro through the so-called DSD-1 epitope embedded in its glycosaminoglycan side chains. Oversulfated CS variants, CS-D from shark cartilage and CS-E from squid cartilage, also possess similar activities. We have proposed that the neuritogenic property of the DSD-1 epitope may be attributable to a distinct CS structure characterized by the disulfated D disaccharide unit [GlcUA(2S)-GalNAc(6S)]. In this study, we assessed neuritogenic potencies of various oversulfated dermatan sulfate (DS) preparations purified from hagfish notochord, the bodies of two kinds of ascidians and embryonic sea urchin, which are characterized by the predominant disulfated disaccharide units of [IdoUA-GalNAc(4S,6S)] (68%), [IdoUA(2S)-GalNAc(4S)] (66%) plus [IdoUA(2S)-GalNAc(6S)] (5%), [IdoUA(2S)-GalNAc (6S)] (>90%), and [IdoUA-GalNAc(4S,6S)] (74%), respectively. They exerted marked neurite outgrowth-promoting activities, resulting in distinct morphological features depending on the individual structural features. Such activities were not observed for a less sulfated DS preparation derived from porcine skin, which has a monosulfated disaccharide unit [IdoUA-Gal-NAc(4S)] as a predominant unit. The neurite outgrowth-promoting activities of these oversulfated DS preparations and DSD-1-PG were eliminated by the specific enzymatic cleavage of GalNAc-IdoUA linkages characteristic of DS using chondroitinase B. In addition, chemical analysis of the glycosaminoglycan side chains of DSD-1-PG revealed the DS-type structures. These observations suggest potential novel neurobiological functions of oversulfated DS structures and may reflect the physiological neuritogenesis during brain development by mammalian oversulfated DS structures exemplified by the DSD-1 epitope.
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Affiliation(s)
- Megumi Hikino
- Department of Biochemistry, Kobe Pharmaceutical University, Higashinada-ku, Kobe 658-8558, Japan
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Moreno-Flores MT, Lim F, Martín-Bermejo MJ, Díaz-Nido J, Avila J, Wandosell F. High level of amyloid precursor protein expression in neurite-promoting olfactory ensheathing glia (OEG) and OEG-derived cell lines. J Neurosci Res 2003; 71:871-81. [PMID: 12605414 DOI: 10.1002/jnr.10527] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
During all the life of a mammal, olfactory ensheathing glia (OEG) permit the entry and navigation of olfactory neuron axons from peripheral to central nervous system (CNS) territory. This physiological characteristic of OEG has been successfully used for promotion of axonal regeneration after CNS injury in animal models. However, cellular and molecular properties responsible for OEG regenerative ability remain to be unveiled. Two approaches may be followed: to carry out genomic or proteomic analysis to detect secreted and/or membrane bound molecules or to examine the expression of molecules previously described as neuritogenic. This is the case of amyloid precursor protein (APP), a neurite-promoting molecule. We have studied the expression of APP by OEG and OEG-derived clonal lines, immortalised with the large T antigen of SV40 (TEG lines). OEG express high levels of APP in vivo and in culture. TEG lines maintained high expression of APP. Western blot analysis showed the presence of high molecular weight forms of APP in OEG, corresponding probably to glycosylated forms and/or to higher expression of the full length APPs. The main APP isoforms present in OEG cultures were APP770 and 751. L-APP isoforms without the exon 15, which are those corresponding with proteoglycan forms, are predominant in glial cells. Our data showed that OEG had three times as much L-APP as astrocytes, which may correlate with OEG neuritogenic capacity. In conclusion APP, a neurite-promoting molecule, is produced by OEG. Its nexin activity, dependent on the Kunitz family of serine protease inhibitors (KPI) domain and/or in combination with its glycosylation level might contribute with other factors to the ability of these cells to foster axonal elongation.
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Affiliation(s)
- M Teresa Moreno-Flores
- Centro de Biología Molecular "Severo Ochoa", Facultad de Ciencias, Universidad Autónoma de Madrid, Madrid, Spain
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Sugaya K. Potential use of stem cells in neuroreplacement therapies for neurodegenerative diseases. INTERNATIONAL REVIEW OF CYTOLOGY 2003; 228:1-30. [PMID: 14667041 DOI: 10.1016/s0074-7696(03)28001-3] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The use of stem cells for neuroreplacement therapy is no longer science fiction--it is science fact. We have succeeded in the development of neural and mesenchymal stem cell transplantation to produce neural cells in the brain. We have also seen improvement in cognitive function following stem cell transplantation in a memory-impaired aged animal model. These results promise a bright future for stem cell therapies in neurodegenerative diseases. Before we begin to think about clinical applications beyond the present preclinical studies, we have to consider the pathophysiological environment of individual diseases and weigh the factors that affect stem cell biology. Here, I not only review potential therapeutic applications of stem cell strategies in neurodegenerative diseases, but also discuss stem cell biology regarding factors that are altered under disease conditions.
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Affiliation(s)
- Kiminobu Sugaya
- Department of Psychiatry, University of Illinois at Chicago, The Psychiatric Institute, Chicago, Illinois 60612, USA
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Deepa SS, Umehara Y, Higashiyama S, Itoh N, Sugahara K. Specific molecular interactions of oversulfated chondroitin sulfate E with various heparin-binding growth factors. Implications as a physiological binding partner in the brain and other tissues. J Biol Chem 2002; 277:43707-16. [PMID: 12221095 DOI: 10.1074/jbc.m207105200] [Citation(s) in RCA: 269] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We previously observed that the cortical neuronal cell adhesion mediated by midkine (MK), a heparin (Hep)-binding growth factor, is specifically inhibited by oversulfated chondroitin sulfate-E (CS-E) (Ueoka, C., Kaneda, N., Okazaki, I., Nadanaka, S., Muramatsu, T., and Sugahara, K. (2000) J. Biol. Chem. 275, 37407-37413) and that CS-E exhibits neurite outgrowth promoting activities toward embryonic rat hippocampal neurons. We have also shown oversulfated CS chains in embryonic chick and rat brains and demonstrated that the CS disaccharide composition changes during brain development. In view of these findings, here we tested the possibility of CS-E interacting with Hep-binding growth factors during development, using squid cartilage CS-E. The binding ability of Hep-binding growth factors (MK, pleiotrophin (PTN), fibroblast growth factor-1 (FGF-1), FGF-2, Hep-binding epidermal growth factor-like growth factor (HB-EGF), FGF-10, FGF-16, and FGF-18) toward [(3)H]CS-E was first tested by a filter binding assay, which demonstrated direct binding of all growth factors, except FGF-1, to CS-E. The bindings were characterized further in an Interaction Analysis system, where all of the growth factors, except FGF-1, gave concentration-dependent and specific bindings. The kinetic constants k(a), k(d), and K(d) suggested that MK, PTN, FGF-16, FGF-18, and HB-EGF bound strongly to CS-E, in comparable degrees to the binding to Hep, whereas the intensity of binding of FGF-2 and FGF-10 toward CS-E was lower than that for Hep. These findings suggest the possibility of CS-E being a binding partner, a coreceptor, or a genuine receptor for various Hep-binding growth factors in the brain and possibly also in other tissues.
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22
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Affiliation(s)
- David Schubert
- Salk Institute, 10010 N. Torrey Pines Road, La Jolla, CA 92037, USA.
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Reddy VP, Obrenovich ME, Atwood CS, Perry G, Smith MA. Involvement of Maillard reactions in Alzheimer disease. Neurotox Res 2002; 4:191-209. [PMID: 12829400 DOI: 10.1080/1029840290007321] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Maillard reactions have been explored by food chemists for many years. It is only recently that the advanced glycation end products (AGEs), the end products of the Maillard reaction, have been detected in a wide variety of diseases such as diabetes, atherosclerosis, cataractogenesis, Parkinson disease and Alzheimer disease (AD). In this review, we discuss the chemistry and biochemistry of AGE-related crosslinks such as pyrraline, pentosidine, carboxymethyllysine (CML), crosslines, imidazolidinones, and dilysine crosslinks (GOLD and MOLD), as well as their possible involvement in neurodegenerative conditions. Pentosidine and CML are found in elevated amounts in the major lesions of the AD brain. Glycation is also implicated in the formation of the paired helical filaments (PHF), a component of the neurofibrillary tangles (NFTs). Amyloid-beta peptide and proteins of the cerebrospinal fluid are also glycated in patients with AD. In order to ameliorate the effects of AGEs on AD pathology, various inhibitors of AGEs have been increasingly explored. It is hoped that understanding of the mechanism of the AGEs formation and their role in the neurodegeneration will result in novel therapeutics for neuroprotection.
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Affiliation(s)
- V Prakash Reddy
- Department of Chemistry, University of Missouri-Rolla, Rolla, MO 65409; Institute of Pathology, Case Western Reserve University, 2085 Adelbert Road, Cleveland, OH 44106, USA.
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Tsuchida K, Shioi J, Yamada S, Boghosian G, Wu A, Cai H, Sugahara K, Robakis NK. Appican, the proteoglycan form of the amyloid precursor protein, contains chondroitin sulfate E in the repeating disaccharide region and 4-O-sulfated galactose in the linkage region. J Biol Chem 2001; 276:37155-60. [PMID: 11479316 DOI: 10.1074/jbc.m105818200] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Chondroitin sulfate (CS)-D and CS-E, which are characterized by oversulfated disaccharide units, have been shown to regulate neuronal adhesion, cell migration, and neurite outgrowth. CS proteoglycans (CSPGs) consist of a core protein to which one or more CS chains are attached via a serine residue. Although several brain CSPGs, including mouse DSD-1-PG/phosphacan, have been found to contain the oversulfated D disaccharide motif, no brain CSPG has been reported to contain the oversulfated E motif. Here we analyzed the CS chain of appican, the CSPG form of the Alzheimer's amyloid precursor protein. Appican is expressed almost exclusively by astrocytes and has been reported to have brain- and astrocyte-specific functions including stimulation of both neural cell adhesion and neurite outgrowth. The present findings show that the CS chain of appican has a molecular mass of 25-50 kDa. This chain contains a significant fraction (14.3%) of the oversulfated E motif GlcUA beta 1-3GalNAc(4,6-O-disulfate). The rest of the chain consists of GlcUA beta 1-3GalNAc(4-O-sulfate) (81.2%) and minor fractions of GlcUA beta 1-3GalNAc and GlcUA beta 1-3GalNAc(6-O-sulfate). We also show that the CS chain of appican contains in its linkage region the 4-O-sulfated Gal structure. Thus, appican is the first example of a specific brain CSPG that contains the E disaccharide unit in its sugar backbone and the 4-O-sulfated Gal residue in its linkage region. The presence of the E unit is consistent with and may explain the neurotrophic activities of appican.
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Affiliation(s)
- K Tsuchida
- Department of Biochemistry, Kobe Pharmaceutical University, Higashinada-ku, Kobe 658-8558, Japan
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25
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Abstract
The extracellular deposition of short amyloid peptides in the brain of patients is thought to be a central event in the pathogenesis of Alzheimer's Disease. The generation of the amyloid peptide occurs via a regulated cascade of cleavage events in its precursor protein, A beta PP. At least three enzymes are responsible for A beta PP proteolysis and have been tentatively named alpha-, beta- and gamma-secretases. The recent identification of several of these secretases is a major leap in the understanding how these secretases regulate amyloid peptide formation. Members of the ADAM family of metalloproteases are involved in the non-amyloidogenic alpha-secretase pathway. The amyloidogenic counterpart pathway is initiated by the recently cloned novel aspartate protease named BACE. The available data are conclusive and crown BACE as the long-sought beta-secretase. This enzyme is a prime candidate drug target for the development of therapy aiming to lower the amyloid burden in the disease. Finally, the gamma-secretases are intimately linked to the function of the presenilins. These multi-transmembrane domain proteins remain intriguing study objects. The hypothesis that the presenilins constitute a complete novel type of protease family, and are cleaving A beta PP within the transmembrane region, remains an issue of debate. Several questions remain unanswered and direct proof that they exert catalytic activity is still lacking. The subcellular localization of presenilins in neurons, their integration in functional multiprotein complexes and the recent identification of additional modulators of gamma-secretase, like nicastrin, indicate already that several players are involved. Nevertheless, the rapidly increasing knowledge in this area is already paving the road towards selective inhibitors of this secretase as well. It is hoped that such drugs, possibly in concert with the experimental vaccination therapies that are currently tested, will lead to a cure of this inexorable disease.
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Affiliation(s)
- D I Dominguez
- Flanders Interuniversitary Institute for Biotechnology and K.U. Leuven, Neuronal Cell Biology and Gene Transfer Laboratory, Center for Human Genetics, Gasthuisberg, B-3000 Leuven, Belgium
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26
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Abstract
Large numbers of different proteoglycans are expressed in tightly regulated spatio-temporal patterns by both the nerve cells (neurons) and the supporting glial cells of the nervous system. Several of these proteoglycans have been shown by studies in vitro to affect the migration of neural precursor cells, the elongation and pathfinding of neurites and the formation and stabilization of synapses. Such processes are important for the accurate wiring of the nervous system, and so it has been postulated that proteoglycans play an essential role during neural development. However, with few exceptions, the phenotypes of null mutations in mice and some human genetic diseases have provided little support for this view. Here we will review recent data from both in vitro and in vivo studies analyzing the function of proteoglycans in the nervous system in order to provide possible explanations for their apparent lack of function.
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Affiliation(s)
- U Hartmann
- Institute for Biochemistry, Medical Faculty, University of Cologne, Cologne, Germany.
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