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Shen T, Shi J, Zhao X, Fu L, Wang N, Zheng X, Chen Y, Li M, Ma C, Liu P, Zhu D. Presenilin 1 Is a Therapeutic Target in Pulmonary Hypertension and Promotes Vascular Remodeling. Am J Respir Cell Mol Biol 2024; 70:468-481. [PMID: 38381098 DOI: 10.1165/rcmb.2022-0426oc] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Accepted: 02/20/2024] [Indexed: 02/22/2024] Open
Abstract
Small muscular pulmonary artery remodeling is a dominant feature of pulmonary arterial hypertension (PAH). PSEN1 affects angiogenesis, cancer, and Alzheimer's disease. We aimed to determine the role of PSEN1 in the pathogenesis of vascular remodeling in pulmonary hypertension (PH). Hemodynamics and vascular remodeling in the Psen1-knockin and smooth muscle-specific Psen1-knockout mice were assessed. The functional partners of PSEN1 were predicted by bioinformatics analysis and biochemical experiments. The therapeutic effect of PH was evaluated by administration of the PSEN1-specific inhibitor ELN318463. We discovered that both the mRNA and protein levels of PSEN1 were increased over time in hypoxic rats, monocrotaline rats, and Su5416/hypoxia mice. Psen1 transgenic mice were highly susceptible to PH, whereas smooth muscle-specific Psen1-knockout mice were resistant to hypoxic PH. STRING analysis showed that Notch1/2/3, β-catenin, Cadherin-1, DNER (delta/notch-like epidermal growth factor-related receptor), TMP10, and ERBB4 appeared to be highly correlated with PSEN1. Immunoprecipitation confirmed that PSEN1 interacts with β-catenin and DNER, and these interactions were suppressed by the catalytic PSEN1 mutations D257A, D385A, and C410Y. PSEN1 was found to mediate the nuclear translocation of the Notch1 intracellular domains and activated RBP-Jκ. Octaarginine-coated liposome-mediated pharmacological inhibition of PSEN1 significantly prevented and reversed the pathological process in hypoxic and monocrotaline-induced PH. PSEN1 essentially drives the pathogenesis of PAH and interacted with the noncanonical Notch ligand DNER. PSEN1 can be used as a promising molecular target for treating PAH. PSEN1 inhibitor ELN318463 can prevent and reverse the progression of PH and can be developed as a potential anti-PAH drug.
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Affiliation(s)
- TingTing Shen
- Institute of Cancer Stem Cell, Dalian Medical University, Dalian, China
- Central Laboratory of Harbin Medical University-Daqing, College of Medical Laboratory Science and Technology, Harbin Medical University (Daqing), Daqing, China; and
| | - JiuCheng Shi
- Central Laboratory of Harbin Medical University-Daqing, College of Medical Laboratory Science and Technology, Harbin Medical University (Daqing), Daqing, China; and
| | - XiJuan Zhao
- Central Laboratory of Harbin Medical University-Daqing, College of Medical Laboratory Science and Technology, Harbin Medical University (Daqing), Daqing, China; and
| | - Li Fu
- Central Laboratory of Harbin Medical University-Daqing, College of Medical Laboratory Science and Technology, Harbin Medical University (Daqing), Daqing, China; and
| | - Na Wang
- Central Laboratory of Harbin Medical University-Daqing, College of Medical Laboratory Science and Technology, Harbin Medical University (Daqing), Daqing, China; and
| | - XiaoDong Zheng
- Central Laboratory of Harbin Medical University-Daqing, College of Medical Laboratory Science and Technology, Harbin Medical University (Daqing), Daqing, China; and
| | - YingLi Chen
- Central Laboratory of Harbin Medical University-Daqing, College of Medical Laboratory Science and Technology, Harbin Medical University (Daqing), Daqing, China; and
| | - MingHui Li
- Central Laboratory of Harbin Medical University-Daqing, College of Medical Laboratory Science and Technology, Harbin Medical University (Daqing), Daqing, China; and
| | - Cui Ma
- Central Laboratory of Harbin Medical University-Daqing, College of Medical Laboratory Science and Technology, Harbin Medical University (Daqing), Daqing, China; and
| | - PiXu Liu
- Institute of Cancer Stem Cell, Dalian Medical University, Dalian, China
| | - DaLing Zhu
- Central Laboratory of Harbin Medical University-Daqing, College of Medical Laboratory Science and Technology, Harbin Medical University (Daqing), Daqing, China; and
- College of Pharmacy, Harbin Medical University, Harbin, China
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Cao J, Hou J, Ping J, Cai D. Advances in developing novel therapeutic strategies for Alzheimer's disease. Mol Neurodegener 2018; 13:64. [PMID: 30541602 PMCID: PMC6291983 DOI: 10.1186/s13024-018-0299-8] [Citation(s) in RCA: 142] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Accepted: 11/28/2018] [Indexed: 12/16/2022] Open
Abstract
Alzheimer's Disease (AD), the most prevalent neurodegenerative disease of aging, affects one in eight older Americans. Nearly all drug treatments tested for AD today have failed to show any efficacy. There is a great need for therapies to prevent and/or slow the progression of AD. The major challenge in AD drug development is lack of clarity about the mechanisms underlying AD pathogenesis and pathophysiology. Several studies support the notion that AD is a multifactorial disease. While there is abundant evidence that amyloid plays a role in AD pathogenesis, other mechanisms have been implicated in AD such as tangle formation and spread, dysregulated protein degradation pathways, neuroinflammation, and loss of support by neurotrophic factors. Therefore, current paradigms of AD drug design have been shifted from single target approach (primarily amyloid-centric) to developing drugs targeted at multiple disease aspects, and from treating AD at later stages of disease progression to focusing on preventive strategies at early stages of disease development. Here, we summarize current strategies and new trends of AD drug development, including pre-clinical and clinical trials that target different aspects of disease (mechanism-based versus non-mechanism based, e.g. symptomatic treatments, lifestyle modifications and risk factor management).
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Affiliation(s)
- Jiqing Cao
- James J Peters VA Medical Center, Research & Development, Bronx, NY 10468 USA
- Department of Neurology, Alzheimer Disease Research Center, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
- The Central Hospital of The Hua Zhong University of Science and Technology, Wuhan, China
| | - Jianwei Hou
- James J Peters VA Medical Center, Research & Development, Bronx, NY 10468 USA
- Department of Neurology, Alzheimer Disease Research Center, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
| | - Jing Ping
- The Central Hospital of The Hua Zhong University of Science and Technology, Wuhan, China
| | - Dongming Cai
- James J Peters VA Medical Center, Research & Development, Bronx, NY 10468 USA
- Department of Neurology, Alzheimer Disease Research Center, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
- The Central Hospital of The Hua Zhong University of Science and Technology, Wuhan, China
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Zuroff L, Daley D, Black KL, Koronyo-Hamaoui M. Clearance of cerebral Aβ in Alzheimer's disease: reassessing the role of microglia and monocytes. Cell Mol Life Sci 2017; 74:2167-2201. [PMID: 28197669 PMCID: PMC5425508 DOI: 10.1007/s00018-017-2463-7] [Citation(s) in RCA: 159] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Revised: 01/07/2017] [Accepted: 01/11/2017] [Indexed: 01/03/2023]
Abstract
Deficiency in cerebral amyloid β-protein (Aβ) clearance is implicated in the pathogenesis of the common late-onset forms of Alzheimer’s disease (AD). Accumulation of misfolded Aβ in the brain is believed to be a net result of imbalance between its production and removal. This in turn may trigger neuroinflammation, progressive synaptic loss, and ultimately cognitive decline. Clearance of cerebral Aβ is a complex process mediated by various systems and cell types, including vascular transport across the blood–brain barrier, glymphatic drainage, and engulfment and degradation by resident microglia and infiltrating innate immune cells. Recent studies have highlighted a new, unexpected role for peripheral monocytes and macrophages in restricting cerebral Aβ fibrils, and possibly soluble oligomers. In AD transgenic (ADtg) mice, monocyte ablation or inhibition of their migration into the brain exacerbated Aβ pathology, while blood enrichment with monocytes and their increased recruitment to plaque lesion sites greatly diminished Aβ burden. Profound neuroprotective effects in ADtg mice were further achieved through increased cerebral recruitment of myelomonocytes overexpressing Aβ-degrading enzymes. This review summarizes the literature on cellular and molecular mechanisms of cerebral Aβ clearance with an emphasis on the role of peripheral monocytes and macrophages in Aβ removal.
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Affiliation(s)
- Leah Zuroff
- Department of Neurosurgery, Maxine Dunitz Neurosurgical Institute, Cedars-Sinai Medical Center, 127 S. San Vicente, AHSP A8115, Los Angeles, CA, 90048, USA.,Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - David Daley
- Department of Neurosurgery, Maxine Dunitz Neurosurgical Institute, Cedars-Sinai Medical Center, 127 S. San Vicente, AHSP A8115, Los Angeles, CA, 90048, USA
| | - Keith L Black
- Department of Neurosurgery, Maxine Dunitz Neurosurgical Institute, Cedars-Sinai Medical Center, 127 S. San Vicente, AHSP A8115, Los Angeles, CA, 90048, USA
| | - Maya Koronyo-Hamaoui
- Department of Neurosurgery, Maxine Dunitz Neurosurgical Institute, Cedars-Sinai Medical Center, 127 S. San Vicente, AHSP A8115, Los Angeles, CA, 90048, USA. .,Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, 90048, USA.
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Caberlotto L, Nguyen TP. A systems biology investigation of neurodegenerative dementia reveals a pivotal role of autophagy. BMC SYSTEMS BIOLOGY 2014; 8:65. [PMID: 24908109 PMCID: PMC4077228 DOI: 10.1186/1752-0509-8-65] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Accepted: 05/20/2014] [Indexed: 11/25/2022]
Abstract
Background Neurodegenerative dementia comprises chronic and progressive illnesses with major clinical features represented by progressive and permanent loss of cognitive and mental performance, including impairment of memory and brain functions. Many different forms of neurodegenerative dementia exist, but they are all characterized by death of specific subpopulation of neurons and accumulation of proteins in the brain. We incorporated data from OMIM and primary molecular targets of drugs in the different phases of the drug discovery process to try to reveal possible hidden mechanism in neurodegenerative dementia. In the present study, a systems biology approach was used to investigate the molecular connections among seemingly distinct complex diseases with the shared clinical symptoms of dementia that could suggest related disease mechanisms. Results Network analysis was applied to characterize an interaction network of disease proteins and drug targets, revealing a major role of metabolism and, predominantly, of autophagy process in dementia and, particularly, in tauopathies. Different phases of the autophagy molecular pathway appear to be implicated in the individual disease pathophysiology and specific drug targets associated to autophagy modulation could be considered for pharmacological intervention. In particular, in view of their centrality and of the direct association to autophagy proteins in the network, PP2A subunits could be suggested as a suitable molecular target for the development of novel drugs. Conclusion The present systems biology investigation identifies the autophagy pathway as a central dis-regulated process in neurodegenerative dementia with a prevalent involvement in diseases characterized by tau inclusion and indicates the disease-specific molecules in the pathway that could be considered for therapy.
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Affiliation(s)
- Laura Caberlotto
- The Microsoft Research, University of Trento Centre for Computational Systems Biology (COSBI), Piazza Manifattura 1, 38068 Rovereto, Italy.
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Mittendorf KF, Deatherage CL, Ohi MD, Sanders CR. Tailoring of membrane proteins by alternative splicing of pre-mRNA. Biochemistry 2012; 51:5541-56. [PMID: 22708632 DOI: 10.1021/bi3007065] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Alternative splicing (AS) of RNA is a key mechanism for diversification of the eukaryotic proteome. In this process, different mRNA transcripts can be produced through altered excision and/or inclusion of exons during processing of the pre-mRNA molecule. Since its discovery, AS has been shown to play roles in protein structure, function, and localization. Dysregulation of this process can result in disease phenotypes. Moreover, AS pathways are promising therapeutic targets for a number of diseases. Integral membrane proteins (MPs) represent a class of proteins that may be particularly amenable to regulation by alternative splicing because of the distinctive topological restraints associated with their folding, structure, trafficking, and function. Here, we review the impact of AS on MP form and function and the roles of AS in MP-related disorders such as Alzheimer's disease.
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Affiliation(s)
- Kathleen F Mittendorf
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
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Massoud F, Gauthier S. Update on the pharmacological treatment of Alzheimer's disease. Curr Neuropharmacol 2010; 8:69-80. [PMID: 20808547 PMCID: PMC2866463 DOI: 10.2174/157015910790909520] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2009] [Revised: 11/25/2009] [Accepted: 12/08/2009] [Indexed: 01/12/2023] Open
Abstract
Alzheimer's disease (AD) is the most common neurodegenerative disorder. Worldwide prevalence of the disease is estimated at more than 24 million cases. With aging of populations, this number will likely increase to more than 80 million cases by the year 2040. The annual incidence worldwide is estimated at 4.6 million cases which is the equivalent of one new case every seven seconds! The pathophysiology of AD is complex and largely misunderstood. It is thought to start with the accumulation of beta-amyloid (αβ) that leads to deposition of insoluble neuritic or senile plaques. Secondary events in this "amyloid cascade" include hyperphosphorylation of the protein tau into neurofibrillary tangles, inflammation, oxidation, and excitotoxicity that eventually cause activation of apoptotis, cell death and neurotransmitter deficits. This review will briefly summarize recent advances in the pathophysiology of AD and focus on the pharmacological treatment of the cognitive and functional symptoms of AD. It will discuss the roles of vascular prevention, cholinesterase inhibitors and an NMDA-antagonist in the management of AD. It will address the issues thought to be related to the lack of persistence or discontinuation of therapy with cholinesterase inhibitors shown in recent studies and some of the solutions proposed. These include setting realistic expectations in light of a neurodegenerative condition and available symptomatic treatments, slowly titrating medications, and using alternate routes of administration. Finally, it will introduce future therapeutic options currently under study.
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Affiliation(s)
- Fadi Massoud
- Department of Medicine, University of Montreal, Centre Hospitalier de l'Université de Montréal (CHUM), Hôpital Notre-Dame, Service de Gériatrie, 1560 Sherbrooke Est, Montreal, Quebec, H2L 4M1.
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Scheper W, Zwart R, Baas F. Alternative splicing in the N-terminus of Alzheimer's presenilin 1. Neurogenetics 2004; 5:223-7. [PMID: 15480879 DOI: 10.1007/s10048-004-0195-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2004] [Accepted: 08/27/2004] [Indexed: 12/17/2022]
Abstract
Presenilin 1 (PS1) is mutated in the majority of familial cases of Alzheimer disease (AD). Although it is clear that PS1 is involved in the processing of the amyloid precursor protein (APP), the exact function of PS1 is still elusive. Human presenilin 1 (PS1) is alternatively spliced, resulting in the presence or absence of a four-amino acid motif, VRSQ, in the PS1 N-terminus. In human tissues, both isoforms are expressed. Here we report that mouse and rat only express the longer PS1 isoform. The presence of this motif introduces a potential phosphorylation site for protein kinase C. Because the splice occurs in the region of PS1 that we have previously shown to bind to rabGDI, this might provide a regulatory mechanism for this interaction. Our data show that the -VRSQ isoform binds rabGDI, but the +VRSQ does not. Moreover, mutation of the putatively phosphorylated threonine in PS1 disrupts the binding to rabGDI, showing its importance for the interaction. To our knowledge this is the first study showing a functional difference between PS1 splice variants. The possible consequences for APP processing and the pathogenesis of AD are discussed.
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Affiliation(s)
- Wiep Scheper
- Neurogenetics Laboratory, Academic Medical Center, Amsterdam, The Netherlands.
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Jhee S, Shiovitz T, Crawford AW, Cutler NR. Beta-amyloid therapies in Alzheimer's disease. Expert Opin Investig Drugs 2001; 10:593-605. [PMID: 11281811 DOI: 10.1517/13543784.10.4.593] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Neurones in the brain produce beta-amyloid fragments from a larger precursor molecule termed the amyloid precursor protein (APP). When released from the cell, these protein fragments may accumulate in extracellular amyloid plaques and consequently hasten the onset and progression of Alzheimer's disease (AD). A beta fragments are generated through the action of specific proteases within the cell. Two of these enzymes, beta- and gamma-secretase, are particularly important in the formation of A beta as they cleave within the APP protein to give rise to the N-terminal and C-terminal ends of the A beta fragment, respectively. Consequently, many researchers are investigating therapeutic approaches that inhibit either beta- or gamma-secretase activity, with the ultimate goal of limiting A beta; production. An alternative AD therapeutic approach that is being investigated is to employ anti-A beta antibodies to dissolve plaques that have already formed. Both of these approaches focus on the possibility that accrual of A beta leads to neuronal degeneration and cognitive impairment characterised by AD and test the hypothesis that limiting A beta deposition in neuritic plaques may be an effective treatment for AD.
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Affiliation(s)
- S Jhee
- California Clinical Trials/Ingenix Pharmaceutical Services, 8501 Wilshire Blvd, Beverly Hills, CA 90211, USA.
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Isoe-Wada K, Urakami K, Wakutani Y, Adachi Y, Arai H, Sasaki H, Nakashima K. Alteration in brain presenilin-1 mRNA expression in sporadic Alzheimer's disease. Eur J Neurol 1999; 6:163-7. [PMID: 10053228 DOI: 10.1111/j.1468-1331.1999.tb00009.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Expression of presenilin-1 (PS-1) mRNA in an alternative splicing at the 3' end of exon 3 was examined in brain tissue, lymphocytes and cultured skin fibroblasts using the RT- polymerase chain reaction (RT-PCR) method. We quantified the relative ratios of the densities of the long form of PS-1 mRNA, which contains a sequence encoding four amino acids (VRSQ, denoted as VRSQ+) to the short form, which lacks the VRSQ sequence (VRSQ-). The brain tissue of subjects with sporadic Alzheimer's disease (AD) had reduced levels of the VRSQ+ form of the PS-1 mRNA compared to a control group. No significant differences appeared in peripheral tissues, such as lymphocytes or cultured skin fibroblasts in AD with control subjects. Changes in the alternative splicing of exon 3 may be specific to the brain and may play an important role in the pathogenesis of sporadic AD.
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Affiliation(s)
- K Isoe-Wada
- Division of Neurology, Institute of Neurological Sciences, Faculty of Medicine, Tottori University, Yonago, Japan
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Xia MQ, Berezovska O, Kim TW, Xia WM, Liao A, Tanzi RE, Selkoe D, Hyman BT. Lack of specific association of presenilin 1 (PS-1) protein with plaques and tangles in Alzheimer's disease. J Neurol Sci 1998; 158:15-23. [PMID: 9667772 DOI: 10.1016/s0022-510x(98)00106-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Missense mutations in the presenilin-1 (PS-1) gene are causally related to the majority of familial early-onset Alzheimer's disease (FAD). PS-1 immunohistochemical expression in normal human brain and in brains with Alzheimer's disease (AD) has so far been controversial. Here, we report a study of PS-1 expression in brains, cell lines and peripheral blood mononuclear cells using a panel of well characterized PS-1-specific antibodies. These antibodies were characterized by immunofluorescent staining of PS-1 transfectants followed by flow cytometric analysis. In human brain, widespread neuronal staining was observed. PS-1 immunoreactivity was primarily confined to neuronal cell bodies and proximal dendrites. Weaker staining of microglia was also detected, in accord with the finding of PS-1 immunoreactivity in monocytes. PS-1 expression is not particularly associated with neurons either containing or spared from neurofibrillary tangles, nor with senile plaques. The level of PS-1 expression does not differ between normal and AD brains. Immunoprecipitation from AD, FAD and control brains revealed only a 32 kDa N-terminal fragment and an 18-20 kDa C-terminal fragment. Little or no full length PS-1 was detected. The enriched presence of PS-1 in neurons implies an important role in neuronal function, however, the lack of apparent association of its expression with AD pathology signifies the need for a better understanding of its pathophysiological role.
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Affiliation(s)
- M Q Xia
- Alzheimer's Research Unit, Department of Neurology, Massachusetts General Hospital-East, Charlestown 02129, USA
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Chauhan NB, Lee JM, Siegel GJ. Na,K-ATPase mRNA levels and plaque load in Alzheimer's disease. J Mol Neurosci 1997; 9:151-66. [PMID: 9481617 DOI: 10.1007/bf02800498] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
UNLABELLED The expression of Na,K-ATPase alpha 1- and alpha 3-mRNAs was analyzed by in situ hybridization in the superior frontal cortex and cerebellum of brains from five Alzheimer's disease (AD), five nondemented age-matched, and three young control subjects. Brains with well-preserved RNA, tested by Northern hybridization of immobilized RNA with [32P]-labeled human beta-actin riboprobe, were chosen for analysis. In situ hybridization was performed on formalin-fixed, 5 microns-thick Paraplast sections with [35S]-labeled riboprobes prepared by in vitro transcription of the respective linearized clones: a 537-bp EcoRI-PstI fragment of alpha 1-cDNA and a 342-bp PstI-EcoRI fragment of alpha 3-cDNA. In cortex, grains related to mRNA were measured by density per unit area in five cortical columns separated by 1.0-1.2 cm in each of two adjacent sections. Each cortical column of 180-micron width was divided into four depths orthogonal to the pial surface between the pia and the white matter. Amyloid plaques were counted in the same regions of adjacent sections. In addition, alpha 3-mRNA grain clusters over individual pyramidal neurons within depth 4 were analyzed. We found the following significant changes (p < 0.05): 1. Increases in total alpha 1-mRNA by 13-19% in AD compared to young and by 7-12% in AD compared to age-matched controls. 2. Decrease in total alpha 3-mRNA by 31-38% in AD compared to young and age-matched controls. 3. Decrease in alpha 3-mRNA content over individual pyramidal perikarya by 14% in normal aged brains without plaques compared to young controls, and by 44% in AD relative to young controls and by 35% compared to age-matched controls. No significant difference (p < 0.2) was found with respect to alpha 1- or alpha 3-mRNA in cerebellar cortex or individual Purkinje cells among any of the groups. In addition, there was a trend toward an inverse correlation between the levels of alpha 3-mRNA and of diffuse plaques, but not of neuritic plaques, in AD cases. IN CONCLUSION 1. The increases in alpha 1-mRNA in AD may be related to an increased reactive gliosis. 2. The declines in alpha 3-mRNA per individual neuron found in normal aging occur prior to the formation of diffuse plaques and are greatly accelerated in AD. 3. The declines in alpha 3-mRNA per neuron found in normal aging may predispose to or potentiate AD pathogenesis.
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Affiliation(s)
- N B Chauhan
- Molecular and Cellular Neuroscience Laboratory, Edward Hines Jr. Veterans Affairs Hospital, IL 60141, USA
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