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Xu ZP, Li L, Bao J, Wang ZH, Zeng J, Liu EJ, Li XG, Huang RX, Gao D, Li MZ, Zhang Y, Liu GP, Wang JZ. Magnesium protects cognitive functions and synaptic plasticity in streptozotocin-induced sporadic Alzheimer's model. PLoS One 2014; 9:e108645. [PMID: 25268773 PMCID: PMC4182554 DOI: 10.1371/journal.pone.0108645] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Accepted: 08/25/2014] [Indexed: 12/15/2022] Open
Abstract
Alzheimer's disease (AD) is characterized by profound synapse loss and impairments of learning and memory. Magnesium affects many biochemical mechanisms that are vital for neuronal properties and synaptic plasticity. Recent studies have demonstrated that the serum and brain magnesium levels are decreased in AD patients; however, the exact role of magnesium in AD pathogenesis remains unclear. Here, we found that the intraperitoneal administration of magnesium sulfate increased the brain magnesium levels and protected learning and memory capacities in streptozotocin-induced sporadic AD model rats. We also found that magnesium sulfate reversed impairments in long-term potentiation (LTP), dendritic abnormalities, and the impaired recruitment of synaptic proteins. Magnesium sulfate treatment also decreased tau hyperphosphorylation by increasing the inhibitory phosphorylation of GSK-3β at serine 9, thereby increasing the activity of Akt at Ser473 and PI3K at Tyr458/199, and improving insulin sensitivity. We conclude that magnesium treatment protects cognitive function and synaptic plasticity by inhibiting GSK-3β in sporadic AD model rats, which suggests a potential role for magnesium in AD therapy.
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Affiliation(s)
- Zhi-Peng Xu
- Department of Pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Key Laboratory of Neurological Disease of National Education Ministry, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Li Li
- Department of Pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Key Laboratory of Neurological Disease of National Education Ministry, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jian Bao
- Department of Pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Key Laboratory of Neurological Disease of National Education Ministry, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Zhi-Hao Wang
- Department of Pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Key Laboratory of Neurological Disease of National Education Ministry, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Juan Zeng
- Department of Pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Key Laboratory of Neurological Disease of National Education Ministry, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - En-Jie Liu
- Department of Pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Key Laboratory of Neurological Disease of National Education Ministry, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xiao-Guang Li
- Department of Pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Key Laboratory of Neurological Disease of National Education Ministry, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Rong-Xi Huang
- Department of Pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Key Laboratory of Neurological Disease of National Education Ministry, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Di Gao
- Department of Pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Key Laboratory of Neurological Disease of National Education Ministry, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Meng-Zhu Li
- Department of Pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Key Laboratory of Neurological Disease of National Education Ministry, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yao Zhang
- Department of Pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Li Yuan Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Gong-Ping Liu
- Department of Pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Key Laboratory of Neurological Disease of National Education Ministry, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jian-Zhi Wang
- Department of Pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Key Laboratory of Neurological Disease of National Education Ministry, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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Jiang Q, Wang L, Guan Y, Xu H, Niu Y, Han L, Wei YP, Lin L, Chu J, Wang Q, Yang Y, Pei L, Wang JZ, Tian Q. Golgin-84-associated Golgi fragmentation triggers tau hyperphosphorylation by activation of cyclin-dependent kinase-5 and extracellular signal-regulated kinase. Neurobiol Aging 2013; 35:1352-63. [PMID: 24368089 DOI: 10.1016/j.neurobiolaging.2013.11.022] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2013] [Revised: 09/23/2013] [Accepted: 11/24/2013] [Indexed: 12/16/2022]
Abstract
Tau hyperphosphorylation is a critical event in Alzheimer's disease, in which the neuronal Golgi fragmentation occurs earlier than tau hyperphosphorylation. However, the intrinsic link between Golgi impairment and tau pathology is missing. By electron microscopy and western blotting, we observed in the present study that the neuronal Golgi fragmentation was increased age-dependently with a correlated tau hyperphosphorylation in the brains of C57BL/6 mice aged from 4 to 16 months. Simultaneously, golgin-84 and Golgi reassembly stacking protein 65, 2 important Golgi matrix proteins, were decreased in the brains of elder mice. Further studies in HEK293/tau cells showed that Golgi-disturbing agents, brefeldin A and nocodazole induced tau hyperphosphorylation. Knockdown of golgin-84, not Golgi reassembly stacking protein 65, by small interfering RNA was sufficient to induce tau hyperphosphorylation, while over-expressing golgin-84 arrested the brefeldin A-induced Golgi fragmentation and tau hyperphosphorylation. Finally, we demonstrated that cyclin-dependent kinase-5 and extracellular signal-regulated kinase were activated after golgin-84 knockdown, and simultaneous inhibition of these kinases abolished the golgin-84 deficit-induced tau hyperphosphorylation. These data suggest Golgi fragmentation could be an upstream event triggering tau hyperphosphorylation through golgin-84 deficit-induced activation of cyclin-dependent kinase-5 and extracellular signal-regulated kinase.
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Affiliation(s)
- Qian Jiang
- Department of Pathology and Pathophysiology, Ultrastructural Pathology Center, Key Laboratory of Neurological Disease of National Education Ministry and Hubei Province, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China; Present address: Department of Dermatology, The First Hospital of Wuhan, Wuhan, China
| | - Lu Wang
- Department of Pathology and Pathophysiology, Ultrastructural Pathology Center, Key Laboratory of Neurological Disease of National Education Ministry and Hubei Province, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yang Guan
- Department of Pathology and Pathophysiology, Ultrastructural Pathology Center, Key Laboratory of Neurological Disease of National Education Ministry and Hubei Province, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Hui Xu
- Department of Pathology and Pathophysiology, Ultrastructural Pathology Center, Key Laboratory of Neurological Disease of National Education Ministry and Hubei Province, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yi Niu
- Department of Pathology and Pathophysiology, Ultrastructural Pathology Center, Key Laboratory of Neurological Disease of National Education Ministry and Hubei Province, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Li Han
- Department of Pathology and Pathophysiology, Ultrastructural Pathology Center, Key Laboratory of Neurological Disease of National Education Ministry and Hubei Province, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yu-Ping Wei
- Department of Pathology and Pathophysiology, Ultrastructural Pathology Center, Key Laboratory of Neurological Disease of National Education Ministry and Hubei Province, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Li Lin
- Department of Pathology and Pathophysiology, Ultrastructural Pathology Center, Key Laboratory of Neurological Disease of National Education Ministry and Hubei Province, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jiang Chu
- Department of Pathology and Pathophysiology, Ultrastructural Pathology Center, Key Laboratory of Neurological Disease of National Education Ministry and Hubei Province, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Qun Wang
- Department of Pathology and Pathophysiology, Ultrastructural Pathology Center, Key Laboratory of Neurological Disease of National Education Ministry and Hubei Province, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Ying Yang
- Department of Pathology and Pathophysiology, Ultrastructural Pathology Center, Key Laboratory of Neurological Disease of National Education Ministry and Hubei Province, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Lei Pei
- Department of Pathology and Pathophysiology, Ultrastructural Pathology Center, Key Laboratory of Neurological Disease of National Education Ministry and Hubei Province, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jian-Zhi Wang
- Department of Pathology and Pathophysiology, Ultrastructural Pathology Center, Key Laboratory of Neurological Disease of National Education Ministry and Hubei Province, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
| | - Qing Tian
- Department of Pathology and Pathophysiology, Ultrastructural Pathology Center, Key Laboratory of Neurological Disease of National Education Ministry and Hubei Province, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
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Steele JW, Gandy S. Apomorphine and Alzheimer Aβ: roles for regulated α cleavage, autophagy, and antioxidation? Ann Neurol 2011; 69:221-5. [PMID: 21387363 DOI: 10.1002/ana.22359] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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Lane RF, Gatson JW, Small SA, Ehrlich ME, Gandy S. Protein kinase C and rho activated coiled coil protein kinase 2 (ROCK2) modulate Alzheimer's APP metabolism and phosphorylation of the Vps10-domain protein, SorL1. Mol Neurodegener 2010; 5:62. [PMID: 21192821 PMCID: PMC3036620 DOI: 10.1186/1750-1326-5-62] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2010] [Accepted: 12/30/2010] [Indexed: 11/10/2022] Open
Abstract
Background Generation of the amyloid β (Aβ) peptide of Alzheimer's disease (AD) is differentially regulated through the intracellular trafficking of the amyloid β precursor protein (APP) within the secretory and endocytic pathways. Protein kinase C (PKC) and rho-activated coiled-coil kinases (ROCKs) are two "third messenger" signaling molecules that control the relative utilization of these two pathways. Several members of the Vps family of receptors (Vps35, SorL1, SorCS1) play important roles in post-trans-Golgi network (TGN) sorting and generation of APP derivatives, including Aβ at the TGN, endosome and the plasma membrane. We now report that Vps10-domain proteins are candidate substrates for PKC and/or ROCK2 and act as phospho-state-sensitive physiological effectors for post-TGN sorting of APP and its derivatives. Results Analysis of the SorL1 cytoplasmic tail revealed multiple consensus sites for phosphorylation by protein kinases. SorL1 was subsequently identified as a phosphoprotein, based on sensitivity of its electrophoretic migration pattern to calf intestine alkaline phosphatase and on its reaction with anti-phospho-serine antibodies. Activation of PKC resulted in increased shedding of the ectodomains of both APP and SorL1, and this was paralleled by an apparent increase in the level of the phosphorylated form of SorL1. ROCK2, the neuronal isoform of another protein kinase, was found to form complexes with SorL1, and both ROCK2 inhibition and ROCK2 knockdown enhanced generation of both soluble APP and Aβ. Conclusion These results highlight the potential importance of SorL1 in elucidating phospho-state sensitive mechanisms in the regulation of metabolism of APP and Aβ by PKC and ROCK2.
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Affiliation(s)
- Rachel F Lane
- Department of Neurology, Mount Sinai School of Medicine, New York NY 10029, USA.
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Mondragón-Rodríguez S, Basurto-Islas G, Lee HG, Perry G, Zhu X, Castellani RJ, Smith MA. Causes versus effects: the increasing complexities of Alzheimer's disease pathogenesis. Expert Rev Neurother 2010; 10:683-91. [PMID: 20420489 DOI: 10.1586/ern.10.27] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Amyloid plaques and neurofibrillary tangles are the hallmarks of Alzheimer's disease and have been the focus of disease etiology and pathogenesis. However, in the larger picture of a complex disease, the precise etiology of the lesions per se, as well as the clinical disease, remain to be defined. In this regard, to date no single process has been identified as a useful target and treatment efforts have shown no meaningful progress. Therefore, alternative ideas that may lead to new and effective treatment options are much needed.
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Domingues SCTS, Henriques AG, Wu W, Da Cruz e Silva EF, Da Cruz e Silva OAB. Altered subcellular distribution of the Alzheimer's amyloid precursor protein under stress conditions. Ann N Y Acad Sci 2007; 1096:184-95. [PMID: 17405930 DOI: 10.1196/annals.1397.085] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Altered metabolism of the Alzheimer's amyloid precursor protein (APP) appears to be a key event in the pathogenesis of Alzheimer's disease (AD), and both altered phosphorylation and oxidative stress appear to affect the production of the toxic Abeta fragment. Our results show that altered processing of APP was observed under conditions of stress induced by sodium azide in the presence of 2-deoxy-D-glucose (2DG). As previously reported, the production of the secreted fragment of APP (sAPP) was inhibited. Using APP-GFP fusion proteins, we show that 2DG causes the accumulation/delay of APP in the endoplasmic reticulum (ER)/Golgi (G). The 751 isoform accumulated preferentially in the G, whereas the 695 isoform was blocked preferentially at the ER. This effect was augmented in the presence of sodium azide. APP subcellular distribution was also affected at the plasma membrane. The involvement of protein phosphorylation in APP subcellular localization was reinforced by the effect of drugs, such as phorbol 12-myristate 13-acetate (PMA), since APP was completely depleted from the membrane in the presence of 2DG and PMA. Thus, the hypothesis that APP is processed in a phosphorylation-dependent manner and that this may be of clinical relevance appears to hold true even under stress conditions. Our results provide evidence for a role of protein phosphorylation in APP sorting under stress conditions and contribute to the understanding of the molecular basis of AD.
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Affiliation(s)
- Sara C T S Domingues
- Neuroscience Laboratory, Centre for Cell Biology, University of Aveiro, Aveiro, Portugal
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Pedrini S, Carter TL, Prendergast G, Petanceska S, Ehrlich ME, Gandy S. Modulation of statin-activated shedding of Alzheimer APP ectodomain by ROCK. PLoS Med 2005; 2:e18. [PMID: 15647781 PMCID: PMC543463 DOI: 10.1371/journal.pmed.0020018] [Citation(s) in RCA: 109] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2004] [Accepted: 11/30/2004] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND Statins are widely used cholesterol-lowering drugs that act by inhibiting HMGCoA reductase, the rate-limiting enzyme in cholesterol biosynthesis. Recent evidence suggests that statin use may be associated with a decreased risk for Alzheimer disease, although the mechanisms underlying this apparent risk reduction are poorly understood. One popular hypothesis for statin action is related to the drugs' ability to activate alpha-secretase-type shedding of the alpha-secretase-cleaved soluble Alzheimer amyloid precursor protein ectodomain (sAPP(alpha)). Statins also inhibit the isoprenoid pathway, thereby modulating the activities of the Rho family of small GTPases-Rho A, B, and C-as well as the activities of Rac and cdc42. Rho proteins, in turn, exert many of their effects via Rho-associated protein kinases (ROCKs). Several cell-surface molecules are substrates for activated alpha-secretase-type ectodomain shedding, and regulation of shedding typically occurs via activation of protein kinase C or extracellular-signal-regulated protein kinases, or via inactivation of protein phosphatase 1 or 2A. However, the possibility that these enzymes play a role in statin-stimulated shedding has been excluded, leading us to investigate whether the Rho/ROCK1 protein phosphorylation pathway might be involved. METHODS AND FINDINGS We found that both atorvastatin and simvastatin stimulated sAPP(alpha) shedding from a neuroblastoma cell line via a subcellular mechanism apparently located upstream of endocytosis. A farnesyl transferase inhibitor also increased sAPP(alpha) shedding, as did a dominant negative form of ROCK1. Most conclusively, a constitutively active ROCK1 molecule inhibited statin-stimulated sAPP(alpha) shedding. CONCLUSION Together, these data suggest that statins exert their effects on shedding of sAPP(alpha) from cultured cells, at least in part, by modulation of the isoprenoid pathway and ROCK1.
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Affiliation(s)
- Steve Pedrini
- 1Farber Institute for Neurosciences, Thomas Jefferson UniversityPhiladelphia, PennsylvaniaUnited States of America
| | - Troy L Carter
- 1Farber Institute for Neurosciences, Thomas Jefferson UniversityPhiladelphia, PennsylvaniaUnited States of America
| | - George Prendergast
- 2Lankenau Institute for Medical Research, WynnewoodPennsylvaniaUnited States of America
| | - Suzana Petanceska
- 3Nathan S. Kline Institute for Psychiatric Research, Department of PsychiatryNew York University School of Medicine, Orangeburg, New YorkUnited States of America
| | - Michelle E Ehrlich
- 1Farber Institute for Neurosciences, Thomas Jefferson UniversityPhiladelphia, PennsylvaniaUnited States of America
| | - Sam Gandy
- 1Farber Institute for Neurosciences, Thomas Jefferson UniversityPhiladelphia, PennsylvaniaUnited States of America
- 2Lankenau Institute for Medical Research, WynnewoodPennsylvaniaUnited States of America
- *To whom correspondence should be addressed. E-mail:
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Vassar R. BACE1: the beta-secretase enzyme in Alzheimer's disease. J Mol Neurosci 2004; 23:105-14. [PMID: 15126696 DOI: 10.1385/jmn:23:1-2:105] [Citation(s) in RCA: 257] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2002] [Accepted: 03/18/2003] [Indexed: 11/11/2022]
Abstract
Data that have accumulated for well over a decade have implicated the beta-amyloid (Abeta) peptide as a central player in the pathogenesis of Alzheimer's disease (AD). Amyloid plaques, composed primarily of Abeta progressively form in the brains of AD patients, and mutations in three genes (amyloid precursor protein [APP] and presenilin 1 and 2 [PS1 and PS2]) cause early-onset familial AD (FAD) by directly increasing production of the toxic, plaque-promoting Abeta42 peptide. Given the strong association between Abeta and AD, it is likely that therapeutic strategies to lower the levels of Abeta in the brain should prove beneficial for the treatment of AD. One such strategy could involve inhibiting the enzymes that generate Abeta. Abeta is a product of catabolism of the large type-I membrane protein APP. Two proteases, called beta- and gamma-secretase, endoproteolyze APP to liberate the Abeta peptide. Recently, the molecules responsible for these proteolytic activities have been identified. Several lines of evidence suggest that the PS1 and PS2 proteins are gamma-secretase, and the identity of beta-secretase has been shown to be the novel transmembrane aspartic protease, beta-site APP-cleaving enzyme 1 (BACE1; also called Asp2 and memapsin 2). BACE2, a protease homologous to BACE1, was also identified, and together the two enzymes define a new family of transmembrane aspartic proteases. BACE1 exhibits all the functional properties of beta-secretase, and as the key enzyme that initiates the formation of Abeta, BACE1 is an attractive drug target for AD. This review discusses the identification and initial characterization of BACE1 and BACE2, and summarizes recent studies of BACE1 knockout mice that have validated BACE1 as the authentic beta-secretase in vivo.
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Affiliation(s)
- Robert Vassar
- The Feinberg School of Medicine, Northwestern University, Department of Cell and Molecular Biology, Chicago, IL 60611, USA.
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Funk OF, Kettmann V, Drimal J, Langer T. Chemical Function Based Pharmacophore Generation of Endothelin-A Selective Receptor Antagonists. J Med Chem 2004; 47:2750-60. [PMID: 15139753 DOI: 10.1021/jm031041j] [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: 11/30/2022]
Abstract
Both quantitative and qualitative chemical function based pharmacophore models of endothelin-A (ET(A)) selective receptor antagonists were generated by using the two algorithms HypoGen and HipHop, respectively, which are implemented in the Catalyst molecular modeling software. The input for HypoGen is a training set of 18 ET(A) antagonists exhibiting IC(50) values ranging between 0.19 nM and 67 microM. The best output hypothesis consists of five features: two hydrophobic (HY), one ring aromatic (RA), one hydrogen bond acceptor (HBA), and one negative ionizable (NI) function. The highest scoring Hip Hop model consists of six features: three hydrophobic (HY), one ring aromatic (RA), one hydrogen bond acceptor (HBA), and one negative ionizable (NI). It is the result of an input of three highly active, selective, and structurally diverse ET(A) antagonists. The predictive power of the quantitative model could be approved by using a test set of 30 compounds, whose activity values spread over 6 orders of magnitude. The two pharmacophores were tested according to their ability to extract known endothelin antagonists from the 3D molecular structure database of Derwent's World Drug Index. Thereby the main part of selective ET(A) antagonistic entries was detected by the two hypotheses. Furthermore, the pharmacophores were used to screen the Maybridge database. Six compounds were chosen from the output hit lists for in vitro testing of their ability to displace endothelin-1 from its receptor. Two of these are new potential lead compounds because they are structurally novel and exhibit satisfactory activity in the binding assay.
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Affiliation(s)
- Oliver F Funk
- Department of Pharmaceutical Chemistry, Institute of Pharmacy, University of Innsbruck, Innrain 52a, A-6020 Innsbruck, Austria.
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Fernández-Vizarra P, Fernández AP, Castro-Blanco S, Encinas JM, Serrano J, Bentura ML, Muñoz P, Martínez-Murillo R, Rodrigo J. Expression of nitric oxide system in clinically evaluated cases of Alzheimer's disease. Neurobiol Dis 2004; 15:287-305. [PMID: 15006699 DOI: 10.1016/j.nbd.2003.10.010] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2003] [Revised: 10/14/2003] [Accepted: 10/18/2003] [Indexed: 11/18/2022] Open
Abstract
The expression of neuronal nitric oxide (nNOS) and inducible nitric oxide (iNOS) as isoforms of the nitric oxide synthase (NOS) as well as nitrotyrosine as an end product of protein nitration was analyzed in sections of temporal cortex taken from postmortem brains of patients with Alzheimer's disease (AD). The patients were evaluated by the Clinical Dementia Rating scale (CDR0-CDR3) and studied in the Memory and Aging Project (MAP) of the Washington University Alzheimer Disease Research Center (ADCR). With the use of immunocytochemical procedures, neurons immunoreactive to nNOS were found to show large and small multipolar and pyramidal morphologies over the entire chronic AD evolution. The iNOS and nitrotyrosine immunoreactivities were also found in pyramidal-like cortical neurons and glial cells. Here, we speculate on the interaction among all specific neurodegenerative changes in AD and nitric oxide as an additional contribution to neuronal death in AD.
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Affiliation(s)
- P Fernández-Vizarra
- Department of Neuroanatomy and Cell Biology, Instituto Cajal (CSIC), E-28002 Madrid, Spain
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Gandy S, Martins RN, Buxbaum J. Molecular and cellular basis for anti-amyloid therapy in Alzheimer disease. Alzheimer Dis Assoc Disord 2004; 17:259-66. [PMID: 14657791 DOI: 10.1097/00002093-200310000-00011] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Sam Gandy
- Farber Institute for Neurosciences, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA.
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Rodrigo J, Fernández-Vizarra P, Castro-Blanco S, Bentura ML, Nieto M, Gómez-Isla T, Martínez-Murillo R, MartInez A, Serrano J, Fernández AP. Nitric oxide in the cerebral cortex of amyloid-precursor protein (SW) Tg2576 transgenic mice. Neuroscience 2004; 128:73-89. [PMID: 15450355 DOI: 10.1016/j.neuroscience.2004.06.030] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/22/2004] [Indexed: 01/12/2023]
Abstract
Changes in the amyloid-peptide (Abeta), neuronal and inducible nitric oxide (NO)synthase (nNOS, iNOS), nitrotyrosine, glial fibrillary acidic protein, and lectin from Lycopersicon esculentum (tomato) were investigated in the cerebral cortex of transgenic mice (Tg2576) to amyloid precursor protein (APP), by immunohistochemistry (bright light, confocal, and electron microscopy). The expression of nitrergic proteins and synthesis of nitric oxide were analyzed by immunoblotting and NOS activity assays, respectively. The cerebral cortex of these transgenic mice showed an age-dependent progressive increase in intraneuronal aggregates of Abeta-peptide and extracellular formation of senile plaques surrounded by numerous microglial and reactive astrocytes. Basically, no changes to nNOS reactivity or expression were found in the cortical mantle of either wild or transgenic mice. This reactivity in wild mice corresponded to numerous large type I and small type II neurons. The transgenic mice showed swollen, twisted, and hypertrophic preterminal and terminal processes of type I neurons, and an increase of the type II neurons. The calcium-dependent NOS enzymatic activity was higher in wild than in the transgenic mice. The iNOS reactivity, expression and calcium-independent enzymatic activity increased in transgenic mice with respect to wild mice, and were related to cortical neurons and microglial cells. The progressive elevation of NO production resulted in a specific pattern of protein nitration in reactive astrocytes. The ultrastructural study carried out in the cortical mantle showed that the neurons contained intracellular aggregates of Abeta-peptide associated with the endoplasmic reticulum, mitochondria, and Golgi apparatus. The endothelial vascular cells also contained Abeta-peptide deposits. This transgenic model might contribute to understand the role of the nitrergic system in the biological changes related to neuropathological progression of Alzheimer's disease.
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Affiliation(s)
- J Rodrigo
- Department of Neuroanatomy and Cell Biology, Instituto Cajal, CSIC, Doctor Arce Avenue 37, 28002 Madrid, Spain.
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Gandy S. Molecular basis for anti-amyloid therapy in the prevention and treatment of Alzheimer's disease. Neurobiol Aging 2002; 23:1009-16. [PMID: 12470796 DOI: 10.1016/s0197-4580(02)00125-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
- Sam Gandy
- Farber Institute for Neurosciences, Thomas Jefferson University, 1025 Walnut Street, Philadelphia, PA 19107, USA.
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14
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Murugesan N, Tellew JE, Gu Z, Kunst BL, Fadnis L, Cornelius LA, Baska RAF, Yang Y, Beyer SM, Monshizadegan H, Dickinson KE, Panchal B, Valentine MT, Chong S, Morrison RA, Carlson KE, Powell JR, Moreland S, Barrish JC, Kowala MC, Macor JE. Discovery of N-isoxazolyl biphenylsulfonamides as potent dual angiotensin II and endothelin A receptor antagonists. J Med Chem 2002; 45:3829-35. [PMID: 12190306 DOI: 10.1021/jm020138n] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The ET(A) receptor antagonist (2) (N-(3,4-dimethyl-5-isoxazolyl)-4'-(2-oxazolyl)-[1,1'-biphenyl]-2-sulfonamide, BMS-193884) shares the same biphenyl core as a large number of AT(1) receptor antagonists, including irbesartan (3). Thus, it was hypothesized that merging the structural elements of 2 with those of the biphenyl AT(1) antagonists (e.g., irbesartan) would yield a compound with dual activity for both receptors. This strategy led to the design, synthesis, and discovery of (15) (4'-[(2-butyl-4-oxo-1,3-diazaspiro[4.4]non-1-en-3-yl)methyl]-N-(3,4-dimethyl-5-isoxazolyl)-2'-[(3,3-dimethyl-2-oxo-1-pyrrolidinyl)methyl]-[1,1'-biphenyl]-2-sulfonamide, BMS-248360) as a potent and orally active dual antagonist of both AT(1) and ET(A) receptors. Compound 15 represents a new approach to treating hypertension.
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Affiliation(s)
- Natesan Murugesan
- Discovery Chemistry and Metabolic and Cardiovascular Drug Discovery, Bristol-Myers Squibb Pharmaceutical Research Institute, Princeton, New Jersey 08543-5400, USA.
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15
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Gandy S, Petanceska S. Regulation of alzheimer beta-amyloid precursor trafficking and metabolism. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2001; 487:85-100. [PMID: 11403168 DOI: 10.1007/978-1-4615-1249-3_7] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Affiliation(s)
- S Gandy
- Department of Psychiatry, New York University, The Nathan S. Kline Institute for Psychiatric Research, Orangeburg 10962, USA
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16
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Gandy S, Petanceska S. Regulation of Alzheimer beta-amyloid precursor trafficking and metabolism. BIOCHIMICA ET BIOPHYSICA ACTA 2000; 1502:44-52. [PMID: 10899430 DOI: 10.1016/s0925-4439(00)00031-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Alzheimer's disease (AD) is characterized by the intracranial accumulation of the 4 kDa amyloid-beta peptide (Abeta), following proteolysis of a approximately 700-amino acid, integral membrane precursor, the Alzheimer amyloid precursor protein (APP). The best evidence causally linking APP to AD has been provided by the discovery of mutations within the APP coding sequence that segregate with disease phenotypes in autosomal dominant forms of familial AD (FAD). Though FAD is rare ( < 10% of all AD), the hallmark features (amyloid plaques, neurofibrillary tangles, synaptic and neuronal loss, neurotransmitter deficits and dementia) are indistinguishable when FAD is compared with typical, common, 'non-familial', or sporadic, AD (SAD). Studies of some clinically relevant mutant APP molecules from FAD families have yielded evidence that APP mutations can lead to the enhanced generation or aggregability of Abeta, consistent with a pathogenic role in AD. Other genetic loci for FAD have been discovered which are distinct from the immediate regulatory and coding regions of the APP gene, indicating that defects in molecules other than APP can also specify cerebral amyloidogenesis and FAD. To date, all APP and non-APP FAD mutations can be demonstrated to have the common feature of promoting amyloidogenesis of Abeta. Epidemiological studies indicate that postmenopausal women on estrogen replacement therapy (ERT) have their relative risk of developing SAD diminished by about one third as compared with age-matched women not receiving ERT [M.X. Tang, D. Jacobs, Y. Stern, K. Marder, P. Schofield, B. Gurland, H. Andrews, R. Mayeux, Effect of estrogen during menopause on risk and age at onset of Alzheimer's disease, Lancet 348 (2000) 429432]. Because of the key role of cerebral Abeta accumulation in initiating AD pathology, it is most attractive that estradiol might modulate SAD risk or age-at-onset by inhibiting Abeta accumulation. A possible mechanistic basis for such a scenario is reviewed here.
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Affiliation(s)
- S Gandy
- Department of Psychiatry, The Nathan S. Kline Institute for Psychiatric Research, New York University, Orangeburg, NY 10962, USA.
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17
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Astles PC, Brown TJ, Halley F, Handscombe CM, Harris NV, Majid TN, McCarthy C, McLay IM, Morley A, Porter B, Roach AG, Sargent C, Smith C, Walsh RJ. Selective ET(A) antagonists. 5. Discovery and structure-activity relationships of phenoxyphenylacetic acid derivatives. J Med Chem 2000; 43:900-10. [PMID: 10715156 DOI: 10.1021/jm990378b] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The fifth paper in this series describes the culmination of our investigations into the development of a potent and selective ET(A) receptor antagonist for the treatment of diseases mediated by ET-1. Receptor site mapping of several ET(A) antagonists prepared previously identified a common cationic binding site which prompted synthesis of phenoxyphenylacetic acid derivative 13a, which showed good in vitro activity (IC(50) 59 nM, rat aortic ET(A)). Optimization of 13a led to the identification of 27b, which exhibited an IC(50) of 4 nM. Although this did not translate into the expected in vivo potency, a compound of comparable in vitro activity, 27a (RPR118031A), showed a far better pharmacokinetic profile and in vivo potency (75 micromol/kg) and was duly proposed and accepted as a development candidate.
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Affiliation(s)
- P C Astles
- Rhône-Poulenc Rorer, Dagenham Research Centre, Rainham Road South, Dagenham, Essex, RM10 7XS U.K
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18
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von Geldern TW, Tasker AS, Sorensen BK, Winn M, Szczepankiewicz BG, Dixon DB, Chiou WJ, Wang L, Wessale JL, Adler A, Marsh KC, Nguyen B, Opgenorth TJ. Pyrrolidine-3-carboxylic acids as endothelin antagonists. 4. Side chain conformational restriction leads to ET(B) selectivity. J Med Chem 1999; 42:3668-78. [PMID: 10479298 DOI: 10.1021/jm990170q] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
When the dialkylacetamide side chain of the ET(A)-selective antagonist ABT-627 is replaced with a 2,6-dialkylacetanilide, the resultant analogues show a complete reversal of receptor selectivity, preferring ET(B) over ET(A). By optimizing the aniline substitution pattern, as well as the alkoxy group on the 2-aryl substituent, it is possible to prepare antagonists with subnanomolar affinity for ET(B) and with selectivities in excess of 4000-fold. A number of these compounds also show promising pharmacokinetic profiles; a useful balance of properties is found in A-192621 (38). Pharmacology studies with A-192621 serve to reveal the role of the ET(B) receptor in modulating blood pressure; the observed hypertensive response to persistent ET(B) blockade is consistent with previous postulates and indicates that ET(B)-selective antagonists may not be suitable as agents for long-term systemic therapy.
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Affiliation(s)
- T W von Geldern
- Metabolic Disease Research and Drug Analysis Department, Pharmaceutical Products Research Division, Abbott Laboratories, Abbott Park, Illinois 60064-6098, USA.
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19
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Neurohormonal Signaling Pathways and the Regulation of Alzheimer beta-Amyloid Precursor Metabolism. Trends Endocrinol Metab 1999; 10:273-279. [PMID: 10461174 DOI: 10.1016/s1043-2760(99)00166-6] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Postmenopausal women on estrogen replacement appear to have their relative risk of developing Alzheimer's disease diminished by about one half. Because brain amyloid accumulation plays a key role in initiating Alzheimer's pathology, it is attractive to postulate that estrogen might modulate Alzheimer's risk by inhibiting amyloid accumulation. Data and cell biological models supporting such a scenario are reviewed here.
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20
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Murugesan N, Gu Z, Stein PD, Bisaha S, Spergel S, Girotra R, Lee VG, Lloyd J, Misra RN, Schmidt J, Mathur A, Stratton L, Kelly YF, Bird E, Waldron T, Liu EC, Zhang R, Lee H, Serafino R, Abboa-Offei B, Mathers P, Giancarli M, Seymour AA, Webb ML, Hunt JT. Biphenylsulfonamide endothelin antagonists: structure-activity relationships of a series of mono- and disubstituted analogues and pharmacology of the orally active endothelin antagonist 2'-amino-N- (3,4-dimethyl-5-isoxazolyl)-4'-(2-methylpropyl)[1, 1'-biphenyl]-2-sulfonamide (BMS-187308). J Med Chem 1998; 41:5198-218. [PMID: 9857090 DOI: 10.1021/jm970872k] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Substitution at the ortho position of N-(3,4-dimethyl-5-isoxazolyl) benzenesulfonamide led to the identification of the biphenylsulfonamides as a novel series of endothelin-A (ETA) selective antagonists. Appropriate substitutions on the pendant phenyl ring led to improved binding as well as functional activity. A hydrophobic group such as isobutyl or isopropoxyl was found to be optimal at the 4'-position. Introduction of an amino group at the 2'-position also led to improved analogues. Combination of the optimal 4'-isobutyl substituent with the 2'-amino function afforded an analogue (20, BMS-187308) with improved ETA binding affinity and functional activity. Compound 20 also has good oral activity in inhibiting the pressor effect caused by an ET-1 infusion in rats. Doses of 10 and 30 micromol/kg iv 20 attenuated the pressor responses due to the administration of exogenous ET-1 to conscious monkeys, indicating that the compound inhibits the in vivo activity of endothelin-1 in nonhuman primates.
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Affiliation(s)
- N Murugesan
- Departments of Chemistry, Cardiovascular Agents, Cardiovascular Biochemistry, and Pharmacology, Bristol-Myers Squibb Pharmaceutical Research Institute, Princeton, New Jersey 08543-4000, USA.
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21
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Sisodia SS, Gallagher M. A role for the beta-amyloid precursor protein in memory? Proc Natl Acad Sci U S A 1998; 95:12074-6. [PMID: 9770440 PMCID: PMC33903 DOI: 10.1073/pnas.95.21.12074] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- S S Sisodia
- Department of Pharmacological and Physiological Sciences, The University of Chicago, 947 E. 58th Street, Abbott 316, Chicago, IL 60637, USA.
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22
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Oostveen JA, Dunn E, Carter DB, Hall ED. Neuroprotective efficacy and mechanisms of novel pyrrolopyrimidine lipid peroxidation inhibitors in the gerbil forebrain ischemia model. J Cereb Blood Flow Metab 1998; 18:539-47. [PMID: 9591846 DOI: 10.1097/00004647-199805000-00009] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
A brief period of bilateral carotid occlusion (BCO)-induced forebrain ischemia in gerbils triggers neuronal degeneration and the subsequent expression of amyloid precursor protein (APP), b-amyloid protein (b-AP), and apolipoprotein E (APO-E) in the selectively vulnerable CA1 region of the hippocampus. The increase in immunoreactivity is secondary to the postischemic degeneration of the CA1 neurons and is largely astrocyte-derived as evidenced by a simultaneous increase in glial fibrillary acidic protein (GFAP) staining. Oxygen radical-induced lipid peroxidation has been strongly suggested to play a role in postischemic neuronal damage and Alzheimer's disease. Recent literature suggests a possible link between early oxidative stress and APP overexpression. Therefore, the present investigation examined the effect of two novel brain-penetrating pyrrolopyrimidine lipid peroxidation inhibitors (PNU-101033E and PNU-104067F) on CA1 neurodegeneration and the subsequent increase in APP, b-AP, APO-E, and GFAP immunostaining at 4 days after a 5-minute episode of forebrain ischemia. Using an antibody for lipid peroxidation-derived malondialdehyde (MDA)-modified proteins, the authors also examined the effects of PNU-104067F on MDA immunostaining 2 days after ischemia, before completion of the neuronal loss. At 2 days, the authors also evaluated microglial activation using an antibody to surface major histocompatibility complex class II antigen expressed by activated microglia. Gerbils were treated at 30 mg/kg orally 30 minutes before the BCO and 2 hours after ischemia, followed by daily dosing for the next day (microglia and MDA) and the successive 3 days for APP, b-AP, APO-E, and GFAP immunostaining. APP and APO-E staining was significantly suppressed by 50% and 66%, respectively, with either compound. b-AP immunoreactivity was decreased 56% with both compounds, and GFAP expression was significantly decreased 53% (PNU-101033E) and 60.5% (PNU-104067F). There was a concomitant partial sparing of the CA1 hippocampal neurons by both PNU-101033E and PNU-104067F (P < .01) as determined by cresyl violet histochemistry. PNU-104067F significantly inhibited lipid peroxidation-derived MDA immunostaining and microglia activation (P < .05) at 48 hours after ischemia. Brain-penetrable lipid peroxidation inhibitors may provide attenuation of various glial response proteins after ischemic injury, probably secondary to neuronal protection.
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Affiliation(s)
- J A Oostveen
- Central Nervous System Diseases Research, Pharmacia & Upjohn, Inc., Kalamazoo, Michigan, USA
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23
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Kaplitt M, Gouras GK, Makimura H, Jovanovic J, Sweeney D, Greengard P, Relkin NR, Gandy S. Apolipoprotein E, A beta-amyloid, and the molecular pathology of Alzheimer's disease. Therapeutic implications. Ann N Y Acad Sci 1996; 802:42-9. [PMID: 8993483 DOI: 10.1111/j.1749-6632.1996.tb32597.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- M Kaplitt
- Cornell University Medical College, New York, New York, USA
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24
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von Geldern TW, Hutchins C, Kester JA, Wu-Wong JR, Chiou W, Dixon DB, Opgenorth TJ. Azole endothelin antagonists. 1. A receptor model explains an unusual structure-activity profile. J Med Chem 1996; 39:957-67. [PMID: 8632419 DOI: 10.1021/jm950591h] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The pseudotetrapeptide FR-139317 is a potent and highly selective antagonist of the endothelin-A (ET(A)) receptor; however, its peptidic nature leads to poor oral absorption characteristics which make it an unlikely drug candidate. In an attempt to improve these properties, we have replaced a portion of the amide bond framework of FR-139317 with a heterocyclic surrogate. The resultant analogs are also ET(A)-selective antagonists, but show a structure-activity profile substantially different from that of the peptidic series, particularly with regard to the requirements for the side chain group that has been incorporated into the heterocycle. The nature of the heterocycle itself also has profound effects on the activity of the compounds. Both of these surprising results can be rationalized through examination of a 3D model of ET ligand--receptor binding that has previously been developed in our laboratories.
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Affiliation(s)
- T W von Geldern
- Aging and Degenerative Diseases Research Department, Abbott Laboratories, Abbott Park, Illinois 60064, USA
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25
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Abstract
Alzheimer's disease is the most common type of progressive and debilitating dementia affecting aged people. In some early--as well as late--onset familial cases, a genetic linkage with chromosomes 14, 21 (early-onset) or 19 (late-onset) has been indicated. Furthermore, a direct or indirect role has been attributed to normal or structurally altered amyloid beta-protein (concentrated in senile plaques) and/or excessively phosphorylated tau protein (located in neurofibrillary tangles). Degeneration of cholinergic neurons and concomitant impairment of cortical and hippocampal neurotransmission lead to cognitive and memory deficits. Several compounds are being tested in attempts to prevent and/or cure Alzheimer's disease, including tacrine, which has very modest efficacy in a sub-group of patients, and new acetylcholinesterase inhibitors. Pilot experiments have also been launched using nerve growth factor (NGF) to prevent or stabilize the processes of cholinergic pathway degeneration. Alternatively, antioxidants, free radical scavengers and/or non steroidal anti-inflammatory agents may be screened as potential therapies for neurodegenerative diseases induced by multiple endogenous and/or exogenous factors. The recent use of transgenic mice, in parallel with other genetic, biochemical and neurobiological systems, in vivo and/or in vitro (cell cultures), should accelerate the discovery and development of specific drugs for the treatment of Alzheimer's disease.
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Affiliation(s)
- M Schorderet
- Département de Pharmacologie, Centre Médical Universitaire, Genève, Switzerland
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26
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Zhang H, Komano H, Fuller RS, Gandy SE, Frail DE. Proteolytic processing and secretion of human beta-amyloid precursor protein in yeast. Evidence for a yeast secretase activity. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(18)46854-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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27
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Svennerholm L, Gottfries CG. Membrane lipids, selectively diminished in Alzheimer brains, suggest synapse loss as a primary event in early-onset form (type I) and demyelination in late-onset form (type II). J Neurochem 1994; 62:1039-47. [PMID: 8113790 DOI: 10.1046/j.1471-4159.1994.62031039.x] [Citation(s) in RCA: 251] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Major membrane lipids were quantified in frontal (Brodmann area 9) and temporal (Brodmann areas 21 and 22) cortices, caudate nucleus, hippocampus, and frontal white matter of 12 cases with Alzheimer's disease (AD) type I (early onset), 21 cases with AD type II (late onset), and 20 age-matched controls. The concentration of gangliosides--a marker for axodendritic arborization--was reduced to 58-70% of the control concentration in all four gray areas (p < 0.0001) and to 81% in frontal white matter (p < 0.01) of AD type I cases, whereas it was only significantly reduced in temporal cortex (p < 0.01), hippocampus (p < 0.05), and frontal white matter (p < 0.05) in AD type II cases. The concentration of phospholipids was also significantly reduced (p < 0.01-0.0001) in all four gray areas of AD type I cases but in no area of AD type II cases. The loss of cholesterol was only 50% of the corresponding phospholipid diminution in AD type I. These results suggested a pronounced loss of nerve endings in AD type I. The characteristic membrane lipid disturbance in AD type II was a loss of myelin lipids. This is the first time a fundamental biochemical difference has been shown between the two major forms of AD.
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Affiliation(s)
- L Svennerholm
- Department of Clinical Neuroscience, University of Göteborg, Sweden
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28
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Hung AY, Selkoe DJ. Selective ectodomain phosphorylation and regulated cleavage of beta-amyloid precursor protein. EMBO J 1994; 13:534-42. [PMID: 8313898 PMCID: PMC394842 DOI: 10.1002/j.1460-2075.1994.tb06291.x] [Citation(s) in RCA: 96] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
The beta-amyloid precursor protein (beta APP) is a highly conserved integral membrane protein expressed in most mammalian tissues and found at highest levels in the nervous system. Cerebral deposition of the amyloid beta-peptide (A beta), derived by proteolysis of beta APP, is an early and invariant feature of Alzheimer's disease. Protein phosphorylation by protein kinase C (PKC) has been found to regulate the metabolism of beta APP into nonamyloidogenic and amyloidogenic derivatives, but both the mechanism of these effects and the nature of beta APP phosphorylation are unknown. When labeled in vivo with [32P]orthophosphate, beta APP was phosphorylated only on serine residues in the N-terminal half of the extracellular domain, resulting in the secretion of phosphorylated soluble beta APP. PKC-mediated stimulation of beta APP secretion and concurrent inhibition of A beta release did not involve enhanced phosphorylation of beta APP and proceeded in the absence of cytoplasmic or extracellular phosphorylation of the precursor. The region of beta APP required for this indirect regulation by PKC was largely restricted to a 64 amino acid stretch around the secretory cleavage site. Moreover, in a truncated molecule designed to release soluble beta APP without the need for proteolytic cleavage, secretion was no longer regulated by PKC. Our data indicate that PKC-mediated pathways play a pivotal role in the control of beta APP metabolism and amyloid formation. However, in contrast to current postulates, this regulation is independent of beta APP phosphorylation and instead involves phosphorylation of other substrates that alter beta APP processing, such as beta APP-cleaving proteases.
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Affiliation(s)
- A Y Hung
- Department of Neurology, Harvard Medical School, Boston, MA 02115
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29
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Gandy S, Greengard P. Regulated cleavage of the Alzheimer amyloid precursor protein: molecular and cellular basis. Biochimie 1994; 76:300-3. [PMID: 7819339 DOI: 10.1016/0300-9084(94)90162-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The relative utilization of alternative processing pathways for APP can be regulated by the activation state of certain protein phosphorylation signal transduction pathways. For example, activation of protein kinase C (PKC), or inactivation of protein phosphatases 1 and 2A, leads to a relative increase in utilization of the nonamyloidogenic, 'alpha-secretase' cleavage pathway for APP processing at the expense of other pathways. The molecular and cellular basis for this regulatory event is unknown. The possible mechanisms of regulated APP cleavage include (either singly or in combination): 1) substrate (ie APP) activation; 2) substrate redistribution; 3) enzyme (ie alpha-secretase) activation; or 4) enzyme redistribution. APP is a phosphoprotein; however, recent evidence from studies of the metabolism of mutant APP molecules suggests that changes in the APP cytoplasmic tail phosphorylation state may not be necessary for the phosphorylation-dependent activation of 'alpha-secretase' cleavage. Further, indirect immunofluorescent studies of the subcellular distribution of APP in the absence or presence of phorbol esters (PKC activators) fail to disclose obvious phorbol-induced redistribution of APP immunoreactivity. Taken together, current data suggest that major candidate phosphorylation-state sensitive targets relevant to the molecular basis of PKC-activated processing (or 'regulated cleavage') of APP include the APP ectodomain as well as secretase enzymes and/or other components of the APP trafficking/processing apparatus. Progress in distinguishing among these possibilities is discussed.
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Affiliation(s)
- S Gandy
- Department of Neurology and Neuroscience, Cornell University Medical College, New York, NY 10021
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30
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Gandy S, Greengard P. Processing of Alzheimer A beta-amyloid precursor protein: cell biology, regulation, and role in Alzheimer disease. INTERNATIONAL REVIEW OF NEUROBIOLOGY 1994; 36:29-50. [PMID: 7822119 DOI: 10.1016/s0074-7742(08)60302-5] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- S Gandy
- Department of Neurology and Neuroscience, Cornell University Medical College, New York, New York 10021
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31
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Studies of APP Biology: Analysis of APP Secretion and Characterization of an APP Homologue, APLP2. ACTA ACUST UNITED AC 1994. [DOI: 10.1007/978-3-662-01135-5_11] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
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32
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Gandy S. Targets for Alzheimer's disease research: from basic mechanisms to rational therapies. Neurobiol Aging 1994; 15 Suppl 2:S157-60. [PMID: 7700442 DOI: 10.1016/0197-4580(94)90195-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- S Gandy
- Department of Neurology and Neuroscience, Cornell University Medical College, New York, NY 10021
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33
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Gandy SE, Caporaso GL, Buxbaum JD, de Cruz Silva O, Iverfeldt K, Nordstedt C, Suzuki T, Czernik AJ, Nairn AC, Greengard P. Protein phosphorylation regulates relative utilization of processing pathways for Alzheimer beta/A4 amyloid precursor protein. Ann N Y Acad Sci 1993; 695:117-21. [PMID: 8239268 DOI: 10.1111/j.1749-6632.1993.tb23038.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The Alzheimer amyloid precursor protein (APP) is a phosphoprotein, and the phosphorylation state of APP at Ser655 can be regulated by protein kinase C, calcium/calmodulin-dependent protein kinase II, and okadaic acid-sensitive protein phosphatases. Other enzymes may also play a role at Ser655 of APP and, perhaps, at other residues. Signal transduction via protein phosphorylation regulates APP metabolism. In particular, APP processing via the nonamyloidogenic secretory cleavage pathway is increased following the activation of protein kinase C or the inactivation of okadaic acid-sensitive protein phosphatases. The mechanism(s) by which protein phosphorylation regulates APP secretory cleavage include (among others): substrate activation, substrate redistribution, protease activation and/or protease redistribution. Current experimental evidence will be discussed, addressing the relative importance of each of these possibilities and the implications for these events in the modulation of beta/A4-amyloidogenesis.
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Affiliation(s)
- S E Gandy
- Laboratory of Molecular and Cellular Neuroscience, Rockefeller University, New York, New York 10021
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34
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Gardella JE, Gorgone GA, Candela L, Ghiso J, Castaño EM, Frangione B, Gorevic PD. High-level expression and in vitro mutagenesis of a fibrillogenic 109-amino-acid C-terminal fragment of Alzheimer's-disease amyloid precursor protein. Biochem J 1993; 294 ( Pt 3):667-74. [PMID: 8379923 PMCID: PMC1134514 DOI: 10.1042/bj2940667] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
We amplified DNA encoding the 3' 109 codons of Alzheimer's-disease amyloid precursor protein (APP) inclusive of the beta protein (A beta) and cytoplasmic domains from cDNA using oligonucleotide primers designed to facilitate cloning into the T7 expression vector pT7Ad23K13. We also modified this construct to generate recombinant molecules incorporating two recently described APP mutants by site-directed mutagenesis. Both native C109 (deletion construct inclusive of the C-terminal 109 residues of APP) and constructs with a single mutation at codon 642 (T-->G, resulting in a substitution of glycine for valine) or a double mutation at codons 595 (G-->T, substituting asparagine for lysine) and 596 (A-->C, substituting leucine for methionine) were expressed in Escherichia coli to levels of 5-20% of total bacterial protein after induction. The major constituent of expressed C109 protein had an apparent molecular mass of 16-18 kDa by SDS/PAGE and appeared to be the full-length construct by size and N-terminal microsequencing. Also present was a 4-5 kDa species that co-purified with C109, constituting only approximately 1% of expressed protein, which was revealed by Western-blot analysis with antibodies specific for A beta epitopes and after biotinylation of purified recombinant C109. This fragment shared N-terminal sequence with, and appeared to arise by proteolysis of, full-length C109 in biosynthetic labelling experiments. C109 spontaneously precipitated after dialysis against NaCl or water, and with prolonged (> 20 weeks) standing was found by electron microscopy to contain a minor (< 5%) fibrillar component that was reactive with antibodies to a C-terminal epitope of APP. Recombinant C109 appears to duplicate some of the biochemical and physicochemical properties of C-terminal A beta-inclusive fragments of APP that have been found in transfected cells, brain cortex and cerebral microvessels.
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Affiliation(s)
- J E Gardella
- Department of Medicine, State University of New York, Stony Brook 11794
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Abstract
Over the past three years, progress in the molecular genetics of familial Alzheimer's disease has been fast and fundamental. The seminal finding that some cases are due to a mutation in the β-amyloid precursor protein (APP) gene has been followed by the discovery of a major additional locus for the disease on chromosome 14. The combined data suggest that the genetic sites accounting for most early-onset familial Alzheimer's disease cases have now been located. In addition, research is revealing the mechanisms by which the genes exert their pathogenicity. This promises to provide the explanatory link between the genes and the clinicopathological syndrome. The ultimate goal, an understanding in similar terms of the much commoner senile, sporadic form of Alzheimer's disease, is now a realistic target.
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Affiliation(s)
- P Harrison
- University Department of Psychiatry, Warneford Hospital, Oxford
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Affiliation(s)
- G J Lees
- Department of Psychiatry and Behavioural Science, School of Medicine, University of Auckland, New Zealand
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Nitsch C, Scotti AL, Monard D, Heim C, Sontag KH. The glia-derived protease nexin 1 persists for over 1 year in rat brain areas selectively lesioned by transient global ischaemia. Eur J Neurosci 1993; 5:292-7. [PMID: 8261109 DOI: 10.1111/j.1460-9568.1993.tb00496.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The re-expression of the developmentally regulated serine protease inhibitor glia-derived nexin (GDN) was investigated 1 year after transient global ischaemia induced by the four-vessel occlusion technique in rats. The CA1 sector of the hippocampus was severely shrunken due to the absence of pyramidal cells, but still clearly discernible due to the continued presence of the parvalbumin-containing GABAergic neurons. In this partially neuron-depleted hippocampus, GDN immunoreactivity was found in reactive astrocytes containing glial fibrillary acidic protein. GDN-positive astrocytes were also found in other lesioned areas, the reticular thalamic nucleus and the cerebellar cortex. Thus, the re-expression of GDN in the adult excitotoxically lesioned brain described previously in the gerbil model of ischaemia persists. The continued presence of the protease inhibitor might disturb the proteolytic balance and lead to the deposition of pathological breakdown products of proteins, e.g. beta-amyloid.
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Affiliation(s)
- C Nitsch
- Anatomisches Institut, Universität Basel, Switzerland
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Chapter 21. Alzheimer's Disease: Current Therapeutic Approaches. ANNUAL REPORTS IN MEDICINAL CHEMISTRY 1993. [DOI: 10.1016/s0065-7743(08)60891-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Gandy SE, Caporaso GL, Ramabhadran TV, Suzuki T, Buxbaum JD, Nordstedt C, Iverfeldt K, Czernik AJ, Nairn AC, Greengard P. Characterization of Alternative Routes for Processing of the Alzheimer ?/A4-Amyloid Precursor Protein. Ann N Y Acad Sci 1992; 674:203-17. [PMID: 1363189 DOI: 10.1111/j.1749-6632.1992.tb27489.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- S E Gandy
- Laboratory of Molecular and Cellular Neuroscience, Rockefeller University, New York, New York 10021
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