1
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Glaubitz S, Zeng R, Rakocevic G, Schmidt J. Update on Myositis Therapy: from Today's Standards to Tomorrow's Possibilities. Curr Pharm Des 2021; 28:863-880. [PMID: 34781868 DOI: 10.2174/1381612827666211115165353] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Accepted: 10/18/2021] [Indexed: 11/22/2022]
Abstract
Inflammatory myopathies, in short, myositis, are heterogeneous disorders that are characterized by inflammation of skeletal muscle and weakness of arms and legs. Research over the past few years has led to a new understanding regarding the pathogenesis of myositis. The new insights include different pathways of the innate and adaptive immune response during the pathogenesis of myositis. The importance of non-inflammatory mechanisms such as cell stress and impaired autophagy has been recently described. New target-specific drugs for myositis have been developed and are currently being tested in clinical trials. In this review, we discuss the mechanisms of action of pharmacological standards in myositis and provide an outlook of future treatment approaches.
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Affiliation(s)
- Stefanie Glaubitz
- Department of Neurology, Muscle Immunobiology Group, Neuromuscular Center, University Medical Center Göttingen, Göttingen. Germany
| | - Rachel Zeng
- Department of Neurology, Muscle Immunobiology Group, Neuromuscular Center, University Medical Center Göttingen, Göttingen. Germany
| | - Goran Rakocevic
- Department of Neurology, Neuromuscular Division, University of Virginia, Charlottesville. United States
| | - Jens Schmidt
- Department of Neurology, Muscle Immunobiology Group, Neuromuscular Center, University Medical Center Göttingen, Göttingen. Germany
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2
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Uddin MS, Yu WS, Lim LW. Exploring ER stress response in cellular aging and neuroinflammation in Alzheimer's disease. Ageing Res Rev 2021; 70:101417. [PMID: 34339860 DOI: 10.1016/j.arr.2021.101417] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 07/27/2021] [Accepted: 07/28/2021] [Indexed: 02/06/2023]
Abstract
One evident hallmark of Alzheimer's disease (AD) is the irregular accumulation of proteins due to changes in proteostasis involving endoplasmic reticulum (ER) stress. To alleviate ER stress and reinstate proteostasis, cells undergo an integrated signaling cascade called the unfolded protein response (UPR) that reduces the number of misfolded proteins and inhibits abnormal protein accumulation. Aging is associated with changes in the expression of ER chaperones and folding enzymes, leading to the impairment of proteostasis, and accumulation of misfolded proteins. The disrupted initiation of UPR prevents the elimination of unfolded proteins, leading to ER stress. In AD, the accumulation of misfolded proteins caused by sustained cellular stress leads to neurodegeneration and neuronal death. Current research has revealed that ER stress can trigger an inflammatory response through diverse transducers of UPR. Although the involvement of a neuroinflammatory component in AD has been documented for decades, whether it is a contributing factor or part of the neurodegenerative events is so far unknown. Besides, a feedback loop occurs between neuroinflammation and ER stress, which is strongly associated with neurodegenerative processes in AD. In this review, we focus on the current research on ER stress and UPR in cellular aging and neuroinflammatory processes, leading to memory impairment and synapse dysfunction in AD.
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3
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Uruha A, Goebel HH, Stenzel W. Updates on the Immunopathology in Idiopathic Inflammatory Myopathies. Curr Rheumatol Rep 2021; 23:56. [PMID: 34212266 DOI: 10.1007/s11926-021-01017-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/21/2021] [Indexed: 10/21/2022]
Abstract
PURPOSE OF REVIEW To review recent advances in immunopathology for idiopathic inflammatory myopathies, focusing on widely available immunohistochemical analyses. RECENT FINDINGS Sarcoplasmic expression of myxovirus resistance protein A (MxA) is specifically observed in all types of dermatomyositis and informs that type I interferons are crucially involved in its pathogenesis. It is a more sensitive diagnostic marker than perifascicular atrophy. Diffuse tiny dots in the sarcoplasm highlighted by p62 immunostaining are characteristically seen in immune-mediated necrotizing myopathy. This feature is linked to a chaperone-assisted selective autophagy pathway. Myofiber invasion by highly differentiated T cells, a marker of which is KLRG1, is specific to inclusion body myositis and has a crucial role in its pathogenesis. The recent advances in immunopathology contribute to increased diagnostic accuracy and a better understanding of the underlying pathophysiology in different types of idiopathic inflammatory myopathies.
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Affiliation(s)
- Akinori Uruha
- Department of Neuropathology, Charité - Universitätsmedizin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health (BIH), Berlin, Germany. .,Department of Neurology, Tokyo Metropolitan Neurological Hospital, 2-6-1 Musashidai, Fuchu, Tokyo, 183-0042, Japan.
| | - Hans-Hilmar Goebel
- Department of Neuropathology, Charité - Universitätsmedizin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health (BIH), Berlin, Germany.,Department of Neuropathology, Universitätsmedizin Mainz, Langenbeckstraße 1, 55131, Mainz, Germany
| | - Werner Stenzel
- Department of Neuropathology, Charité - Universitätsmedizin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health (BIH), Berlin, Germany.,Leibniz Science Campus Chronic Inflammation, Charitéplatz 1, 10117, Berlin, Germany
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4
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Nie Y, Li Y, Xu Y, Jiao Y, Li W. Long non-coding RNA BACE1-AS is an independent unfavorable prognostic factor in liver cancer. Oncol Lett 2020; 20:202. [PMID: 32963608 PMCID: PMC7491030 DOI: 10.3892/ol.2020.12065] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Accepted: 04/01/2020] [Indexed: 02/06/2023] Open
Abstract
Liver cancer is one of the leading causes of cancer-associated deaths with incidence rates continuously on the rise. Biomarkers are urgently required for early diagnosis and better prognostic classification, which is essential for risk stratification and optimizing treatment strategies in clinical settings. By analyzing the data extracted from The Cancer Genome Atlas database using R, the long noncoding RNA (lncRNA) β-site APP-cleaving enzyme 1 antisense (BACE1-AS) was discovered to have both high diagnostic and prognostic values in liver cancer, which could serve as a promising biomarker in clinical settings. Precisely, lncRNA BACE1-AS is significantly overexpressed in liver cancer and its levels vary within different subgroups, suggesting its tumorigenic role. Furthermore, higher BACE1-AS predicts poorer overall survival and relapse-free survival outcomes. Overall, the present study demonstrated that BACE1-AS may be involved in liver cancer progression and could serve as a promising biomarker for diagnosis and prognostic evaluation.
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Affiliation(s)
- Yuanyuan Nie
- Stem Cell and Cancer Center, First Hospital, Jilin University, Changchun, Jilin 130021, P.R. China
| | - Yanqing Li
- Department of Pathophysiology, College of Basic Medical Sciences, Jilin University, Changchun, Jilin 130021, P.R. China
| | - Yanhui Xu
- Department of Digestive, China-Japan Union Hospital, Jilin University, Changchun, Jilin 130031, P.R. China
| | - Yan Jiao
- Department of Hepatobiliary and Pancreatic Surgery, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China
| | - Wei Li
- Stem Cell and Cancer Center, First Hospital, Jilin University, Changchun, Jilin 130021, P.R. China
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5
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Balakrishnan A, Aggarwal R, Agarwal V, Gupta L. Inclusion body myositis in the rheumatology clinic. Int J Rheum Dis 2020; 23:1126-1135. [PMID: 32662192 DOI: 10.1111/1756-185x.13902] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 06/02/2020] [Accepted: 06/09/2020] [Indexed: 01/25/2023]
Affiliation(s)
- Anu Balakrishnan
- Department of Clinical Immunology Sanjay Gandhi Postgraduate Institute of Medical Sciences Lucknow India
| | - Rohit Aggarwal
- Division of Rheumatology and Clinical Immunology Arthritis and Autoimmunity Center (Falk) UPMC Myositis Center University of Pittsburgh Pittsburgh Pennsylvania USA
| | - Vikas Agarwal
- Department of Clinical Immunology Sanjay Gandhi Postgraduate Institute of Medical Sciences Lucknow India
| | - Latika Gupta
- Department of Clinical Immunology Sanjay Gandhi Postgraduate Institute of Medical Sciences Lucknow India
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Wang IK, Palanisamy K, Sun KT, Yu SH, Yu TM, Li CH, Lin FY, Chou AK, Wang GJ, Chen KB, Li CY. The functional interplay of lncRNA EGOT and HuR regulates hypoxia-induced autophagy in renal tubular cells. J Cell Biochem 2020; 121:4522-4534. [PMID: 32030803 DOI: 10.1002/jcb.29669] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Accepted: 01/16/2020] [Indexed: 12/20/2022]
Abstract
Autophagy, an important cellular homeostatic mechanism regulates cell survival under stress and protects against acute kidney injury. However, the role of long noncoding RNA (lncRNA) in autophagy regulation in renal tubular cells (HK-2) is unclear. The study was aimed to understand the importance of lncRNA in hypoxia-induced autophagy in HK-2 cells. LncRNA eosinophil granule ontogeny transcript (EGOT) was identified as autophagy-associated lncRNA under hypoxia. The lncRNA EGOT expression was significantly downregulated in renal tubular cells during hypoxia-induced autophagy. Gain- and loss-of-EGOT functional studies revealed that EGOT overexpression reduced autophagy by downregulation of ATG7, ATG16L1, LC3II expressions and LC 3 puncta while EGOT knockdown reversed the suppression of autophagy. Importantly, RNA-binding protein, (ELAVL1)/Hu antigen R (HuR) binds and stabilizes the EGOT expression under normoxia and ATG7/16L1 expressions under hypoxia. Furthermore, HuR mediated stabilization of ATG7/16L1 expressions under hypoxia causes a decline in EGOT levels and thereby promotes autophagy. Altogether, the study first reveals the functional interplay of lncRNA EGOT and HuR on the posttranscriptional regulation of the ATG7/16L1 expressions. Thus, the HuR/EGOT/ATG7/16L1 axis is crucial for hypoxia-induced autophagy in renal tubular cells.
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Affiliation(s)
- I-Kuan Wang
- Graduate Institute of Biomedical Sciences, China Medical University, Taichung, Taiwan.,Division of Nephrology, China Medical University Hospital, Taichung, Taiwan.,Department of Internal Medicine, College of Medicine, China Medical University, Taichung, Taiwan
| | - Kalaiselvi Palanisamy
- Graduate Institute of Biomedical Sciences, China Medical University, Taichung, Taiwan
| | - Kuo-Ting Sun
- Department of Pediatric Dentistry, China Medical University Hospital, Taichung, Taiwan.,School of Dentistry, China Medical University, Taichung, Taiwan
| | - Shao-Hua Yu
- Graduate Institute of Biomedical Sciences, China Medical University, Taichung, Taiwan.,Department of Emergency Medicine, China Medical University Hospital, Taichung, Taiwan
| | - Tung-Min Yu
- Graduate Institute of Biomedical Sciences, China Medical University, Taichung, Taiwan.,Division of Nephrology, Department of Internal Medicine, Taichung Veterans General Hospital, Taichung, Taiwan
| | - Ching-Hao Li
- Graduate Institute of Biomedical Sciences, China Medical University, Taichung, Taiwan
| | - Feng-Yen Lin
- Department of Internal Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.,Division of Cardiology and Cardiovascular Research Center, Taipei Medical University Hospital, Taipei, Taiwan
| | - An-Kuo Chou
- School of Medicine, China Medical University, Taichung, Taiwan.,Department of Anesthesiology, China Medical University Hospital, Taichung, Taiwan
| | - Guei-Jane Wang
- Graduate Institute of Biomedical Sciences, China Medical University, Taichung, Taiwan.,Department of Medical Research, China Medical University Hospital, Taichung, Taiwan.,Department of Health and Nutrition Biotechnology, Asia University, Taichung, Taiwan
| | - Kuen-Bao Chen
- School of Medicine, China Medical University, Taichung, Taiwan.,Department of Anesthesiology, China Medical University Hospital, Taichung, Taiwan
| | - Chi-Yuan Li
- Graduate Institute of Biomedical Sciences, China Medical University, Taichung, Taiwan.,Department of Anesthesiology, China Medical University Hospital, Taichung, Taiwan
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7
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Clinical, Histological, and Immunohistochemical Findings in Inclusion Body Myositis. BIOMED RESEARCH INTERNATIONAL 2018; 2018:5069042. [PMID: 29780824 PMCID: PMC5893008 DOI: 10.1155/2018/5069042] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Revised: 12/15/2017] [Accepted: 12/27/2017] [Indexed: 11/17/2022]
Abstract
Sporadic inclusion body myositis (sIBM) is considered the most common acquired myopathy aged over 50 years. The disease is characterized by a particular process of muscle degeneration characterized by abnormal deposit of protein aggregates in association with inflammation. The aim of this study was to present clinical and muscle histopathological findings, including immunostaining for LC3B, p62, α-synuclein, and TDP-43, in 18 patients with sIBM. The disease predominated in males (61%) and European descendants, with onset of clinical manifestations around 59 years old. The most common symptoms were muscle weakness, falls, dysphagia, and weight loss. Hypertension was the main comorbidity. Most of the cases presented with paresis predominantly proximal in lower limbs and distal in upper limbs. Immunosuppressive treatment showed to be not effective. Muscle histological findings included dystrophic changes, endomysial inflammation, increased lysosomal activity, and presence of rimmed vacuoles and of beta-amyloid accumulation, in addition to high frequency of mitochondrial changes. There was increased expression of LC3B, p62, α-synuclein, and TDP-43 in muscle biopsies. The sIBM has characteristic clinical and histological findings, and the use of degeneration and autophagic markers can be useful for the diagnosis.
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Greco S, Zaccagnini G, Fuschi P, Voellenkle C, Carrara M, Sadeghi I, Bearzi C, Maimone B, Castelvecchio S, Stellos K, Gaetano C, Menicanti L, Martelli F. Increased BACE1-AS long noncoding RNA and β-amyloid levels in heart failure. Cardiovasc Res 2017; 113:453-463. [DOI: 10.1093/cvr/cvx013] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Accepted: 01/25/2017] [Indexed: 01/18/2023] Open
Affiliation(s)
- Simona Greco
- Molecular Cardiology Laboratory, IRCCS Policlinico San Donato, Via Morandi, 30 20097 San Donato, Milanese, Milan, Italy
| | - Germana Zaccagnini
- Molecular Cardiology Laboratory, IRCCS Policlinico San Donato, Via Morandi, 30 20097 San Donato, Milanese, Milan, Italy
| | - Paola Fuschi
- Molecular Cardiology Laboratory, IRCCS Policlinico San Donato, Via Morandi, 30 20097 San Donato, Milanese, Milan, Italy
| | - Christine Voellenkle
- Molecular Cardiology Laboratory, IRCCS Policlinico San Donato, Via Morandi, 30 20097 San Donato, Milanese, Milan, Italy
| | - Matteo Carrara
- Molecular Cardiology Laboratory, IRCCS Policlinico San Donato, Via Morandi, 30 20097 San Donato, Milanese, Milan, Italy
| | - Iman Sadeghi
- Molecular Cardiology Laboratory, IRCCS Policlinico San Donato, Via Morandi, 30 20097 San Donato, Milanese, Milan, Italy
| | - Claudia Bearzi
- Institute of Cell Biology and Neurobiology (IBCN), National Research Council of Italy (CNR), Monterotondo Scalo, Rome, Italy
| | - Biagina Maimone
- Molecular Cardiology Laboratory, IRCCS Policlinico San Donato, Via Morandi, 30 20097 San Donato, Milanese, Milan, Italy
| | | | - Konstantinos Stellos
- Laboratory of RNA Metabolism and Vascular Inflammation, Institute of Cardiovascular Regeneration, Centre of Molecular Medicine, Goethe University Frankfurt, Frankfurt/Main, Germany
| | - Carlo Gaetano
- Division of Cardiovascular Epigenetics, Department of Cardiology and Internal Medicine Clinic III, Department of Cardiology, Goethe University, Frankfurt/Main, Germany
| | - Lorenzo Menicanti
- Department of Cardiac Surgery, IRCCS Policlinico San Donato, Milan, Italy
| | - Fabio Martelli
- Molecular Cardiology Laboratory, IRCCS Policlinico San Donato, Via Morandi, 30 20097 San Donato, Milanese, Milan, Italy
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9
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Zhao HY, Wu HJ, He JL, Zhuang JH, Liu ZY, Huang LQ, Zhao ZX. Chronic Sleep Restriction Induces Cognitive Deficits and Cortical Beta-Amyloid Deposition in Mice via BACE1-Antisense Activation. CNS Neurosci Ther 2017; 23:233-240. [PMID: 28145081 DOI: 10.1111/cns.12667] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 11/27/2016] [Accepted: 11/29/2016] [Indexed: 12/11/2022] Open
Abstract
AIMS To clarify the correlation between chronic sleep restriction (CSR) and sporadic Alzheimer disease (AD), we determined in wild-type mice the impact of CSR, on cognitive performance, beta-amyloid (Aβ) peptides, and its feed-forward regulators regarding AD pathogenesis. METHODS Sixteen nine-month-old C57BL/6 male mice were equally divided into the CSR and control groups. CSR was achieved by application of a slowly rotating drum for 2 months. The Morris water maze test was used to assess cognitive impairment. The concentrations of Aβ peptides, amyloid precursor protein (APP) and β-secretase 1 (BACE1), and the mRNA levels of BACE1 and BACE1-antisense (BACE1-AS) were measured. RESULTS Following CSR, impairments of spatial learning and memory consolidation were observed in the mice, accompanied by Aβ plaque deposition and an increased Aβ concentration in the prefrontal and temporal lobe cortex. CSR also upregulated the β-secretase-induced cleavage of APP by increasing the protein and mRNA levels of BACE1, particularly the BACE1-AS. CONCLUSIONS This study shows that a CSR accelerates AD pathogenesis in wild-type mice. An upregulation of the BACE1 pathway appears to participate in both cortical Aβ plaque deposition and memory impairment caused by CSR. BACE1-AS is likely activated to initiate a cascade of events that lead to AD pathogenesis. Our study provides, therefore, a molecular mechanism that links CSR to sporadic AD.
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Affiliation(s)
- Hong-Yi Zhao
- Department of Neurology, Changzheng Hospital, Second Military Medical University, Shanghai, China
| | - Hui-Juan Wu
- Department of Neurology, Changzheng Hospital, Second Military Medical University, Shanghai, China
| | - Jia-Lin He
- Academy of Clinical Medicine, Second Military Medical University, Shanghai, China
| | - Jian-Hua Zhuang
- Department of Neurology, Changzheng Hospital, Second Military Medical University, Shanghai, China
| | - Zhen-Yu Liu
- Department of Neurology, Changzheng Hospital, Second Military Medical University, Shanghai, China
| | - Liu-Qing Huang
- Department of Neurology, Changzheng Hospital, Second Military Medical University, Shanghai, China
| | - Zhong-Xin Zhao
- Department of Neurology, Changzheng Hospital, Second Military Medical University, Shanghai, China
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10
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Abstract
All living organisms sense and respond to harmful changes in their intracellular and extracellular environment through complex signaling pathways that lead to changes in gene expression and cellular function in order to maintain homeostasis. Long non-coding RNAs (lncRNAs), a large and heterogeneous group of functional RNAs, play important roles in cellular response to stressful conditions. lncRNAs constitute a significant fraction of the genes differentially expressed in response to diverse stressful stimuli and, once induced, contribute to the regulation of downstream cellular processes, including feedback regulation of key stress response proteins. While many lncRNAs seem to be induced in response to a specific stress, there is significant overlap between lncRNAs induced in response to different stressful stimuli. In addition to stress-induced RNAs, several constitutively expressed lncRNAs also exert a strong regulatory impact on the stress response. Although our understanding of the contribution of lncRNAs to the cellular stress response is still highly rudimentary, the existing data point to the presence of a complex network of lncRNAs, miRNAs, and proteins in regulation of the cellular response to stress.
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Affiliation(s)
- Saba Valadkhan
- Department of Molecular Biology and Microbiology, Case Western Reserve University School of Medicine, Cleveland, OH, 44106, USA.
| | - Alberto Valencia-Hipólito
- Department of Molecular Biology and Microbiology, Case Western Reserve University School of Medicine, Cleveland, OH, 44106, USA
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11
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Catalán-García M, Garrabou G, Morén C, Guitart-Mampel M, Gonzalez-Casacuberta I, Hernando A, Gallego-Escuredo JM, Yubero D, Villarroya F, Montero R, O-Callaghan AS, Cardellach F, Grau JM. BACE-1, PS-1 and sAPPβ Levels Are Increased in Plasma from Sporadic Inclusion Body Myositis Patients: Surrogate Biomarkers among Inflammatory Myopathies. Mol Med 2015; 21:817-823. [PMID: 26552061 DOI: 10.2119/molmed.2015.00168] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Accepted: 10/27/2015] [Indexed: 12/26/2022] Open
Abstract
Sporadic inclusion body myositis (sIBM) is a rare disease that is difficult to diagnose. Muscle biopsy provides three prominent pathological findings: inflammation, mitochondrial abnormalities and fibber degeneration, represented by the accumulation of protein depots constituted by β-amyloid peptide, among others. We aim to perform a screening in plasma of circulating molecules related to the putative etiopathogenesis of sIBM to determine potential surrogate biomarkers for diagnosis. Plasma from 21 sIBM patients and 20 age- and gender-paired healthy controls were collected and stored at -80°C. An additional population of patients with non-sIBM inflammatory myopathies was also included (nine patients with dermatomyositis and five with polymyositis). Circulating levels of inflammatory cytokines (interleukin [IL]-6 and tumor necrosis factor [TNF]-α), mitochondrial-related molecules (free plasmatic mitochondrial DNA [mtDNA], fibroblast growth factor-21 [FGF-21] and coenzyme-Q10 [CoQ]) and amyloidogenic-related molecules (beta-secretase-1 [BACE-1], presenilin-1 [PS-1], and soluble Aβ precursor protein [sAPPβ]) were assessed with magnetic bead-based assays, real-time polymerase chain reaction, enzyme-linked immunosorbent assay (ELISA) and high-pressure liquid chromatography (HPLC). Despite remarkable trends toward altered plasmatic expression of inflammatory and mitochondrial molecules (increased IL-6, TNF-α, circulating mtDNA and FGF-21 levels and decreased content in CoQ), only amyloidogenic degenerative markers including BACE-1, PS-1 and sAPPβ levels were significantly increased in plasma from sIBM patients compared with controls and other patients with non-sIBM inflammatory myopathies (p < 0.05). Inflammatory, mitochondrial and amyloidogenic degeneration markers are altered in plasma of sIBM patients confirming their etiopathological implication in the disease. Sensitivity and specificity analysis show that BACE-1, PS-1 and sAPPβ represent a good predictive noninvasive tool for the diagnosis of sIBM, especially in distinguishing this disease from polymyositis.
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Affiliation(s)
- Marc Catalán-García
- Laboratory of Muscle Research and Mitochondrial Function, Cellex-IDIBAPS, Faculty of Medicine, University of Barcelona, Department of Internal Medicine, Hospital Clinic of Barcelona, Barcelona, Spain
| | - Glòria Garrabou
- Laboratory of Muscle Research and Mitochondrial Function, Cellex-IDIBAPS, Faculty of Medicine, University of Barcelona, Department of Internal Medicine, Hospital Clinic of Barcelona, Barcelona, Spain
| | - Constanza Morén
- Laboratory of Muscle Research and Mitochondrial Function, Cellex-IDIBAPS, Faculty of Medicine, University of Barcelona, Department of Internal Medicine, Hospital Clinic of Barcelona, Barcelona, Spain
| | - Mariona Guitart-Mampel
- Laboratory of Muscle Research and Mitochondrial Function, Cellex-IDIBAPS, Faculty of Medicine, University of Barcelona, Department of Internal Medicine, Hospital Clinic of Barcelona, Barcelona, Spain
| | - Ingrid Gonzalez-Casacuberta
- Laboratory of Muscle Research and Mitochondrial Function, Cellex-IDIBAPS, Faculty of Medicine, University of Barcelona, Department of Internal Medicine, Hospital Clinic of Barcelona, Barcelona, Spain
| | - Adriana Hernando
- Laboratory of Muscle Research and Mitochondrial Function, Cellex-IDIBAPS, Faculty of Medicine, University of Barcelona, Department of Internal Medicine, Hospital Clinic of Barcelona, Barcelona, Spain
| | - Jose Miquel Gallego-Escuredo
- Department of Biochemistry and Molecular Biology, Institute of Biomedicine (University of Barcelona), University of Barcelona, and CIBEROBN, Barcelona, Spain
| | - Dèlia Yubero
- Clinical Biochemistry Department, Hospital Sant Joan de Déu, Barcelona, Spain, and CIBERER, Valencia, Spain
| | - Francesc Villarroya
- Department of Biochemistry and Molecular Biology, Institute of Biomedicine (University of Barcelona), University of Barcelona, and CIBEROBN, Barcelona, Spain
| | - Raquel Montero
- Clinical Biochemistry Department, Hospital Sant Joan de Déu, Barcelona, Spain, and CIBERER, Valencia, Spain
| | | | - Francesc Cardellach
- Laboratory of Muscle Research and Mitochondrial Function, Cellex-IDIBAPS, Faculty of Medicine, University of Barcelona, Department of Internal Medicine, Hospital Clinic of Barcelona, Barcelona, Spain
| | - Josep Maria Grau
- Laboratory of Muscle Research and Mitochondrial Function, Cellex-IDIBAPS, Faculty of Medicine, University of Barcelona, Department of Internal Medicine, Hospital Clinic of Barcelona, Barcelona, Spain
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12
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Askanas V, Engel WK, Nogalska A. Sporadic inclusion-body myositis: A degenerative muscle disease associated with aging, impaired muscle protein homeostasis and abnormal mitophagy. Biochim Biophys Acta Mol Basis Dis 2014; 1852:633-43. [PMID: 25241263 DOI: 10.1016/j.bbadis.2014.09.005] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Revised: 09/09/2014] [Accepted: 09/10/2014] [Indexed: 01/13/2023]
Abstract
Sporadic inclusion-body myositis (s-IBM) is the most common degenerative muscle disease in which aging appears to be a key risk factor. In this review we focus on several cellular molecular mechanisms responsible for multiprotein aggregation and accumulations within s-IBM muscle fibers, and their possible consequences. Those include mechanisms leading to: a) accumulation in the form of aggregates within the muscle fibers, of several proteins, including amyloid-β42 and its oligomers, and phosphorylated tau in the form of paired helical filaments, and we consider their putative detrimental influence; and b) protein misfolding and aggregation, including evidence of abnormal myoproteostasis, such as increased protein transcription, inadequate protein disposal, and abnormal posttranslational modifications of proteins. Pathogenic importance of our recently demonstrated abnormal mitophagy is also discussed. The intriguing phenotypic similarities between s-IBM muscle fibers and the brains of Alzheimer and Parkinson's disease patients, the two most common neurodegenerative diseases associated with aging, are also discussed. This article is part of a Special Issue entitled: Neuromuscular Diseases: Pathology and Molecular Pathogenesis.
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Affiliation(s)
- Valerie Askanas
- USC Neuromuscular Center, Department of Neurology, University of Southern California Keck School of Medicine, Good Samaritan Hospital, Los Angeles, CA, USA.
| | - W King Engel
- USC Neuromuscular Center, Department of Neurology, University of Southern California Keck School of Medicine, Good Samaritan Hospital, Los Angeles, CA, USA
| | - Anna Nogalska
- USC Neuromuscular Center, Department of Neurology, University of Southern California Keck School of Medicine, Good Samaritan Hospital, Los Angeles, CA, USA
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13
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Mohanty V, Gökmen-Polar Y, Badve S, Janga SC. Role of lncRNAs in health and disease-size and shape matter. Brief Funct Genomics 2014; 14:115-29. [PMID: 25212482 DOI: 10.1093/bfgp/elu034] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Most of the mammalian genome including a large fraction of the non-protein coding transcripts has been shown to be transcribed. Studies related to these non-coding RNA molecules have predominantly focused on smaller molecules like microRNAs. In contrast, long non-coding RNAs (lncRNAs) have long been considered to be transcriptional noise. Accumulating evidence suggests that lncRNAs are involved in key cellular and developmental processes. Several critical questions regarding functions and properties of lncRNAs and their circular forms remain to be answered. Increasing evidence from high-throughput sequencing screens also suggests the involvement of lncRNAs in diseases such as cancer, although the underlying mechanisms still need to be elucidated. Here, we discuss the current state of research in the field of lncRNAs, questions that need to be addressed in light of recent genome-wide studies documenting the landscape of lncRNAs, their functional roles and involvement in diseases. We posit that with the availability of high-throughput data sets it is not only possible to improve methods for predicting lncRNAs but will also facilitate our ability to elucidate their functions and phenotypes by using integrative approaches.
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Fonseca AC, Oliveira CR, Pereira CF, Cardoso SM. Loss of proteostasis induced by amyloid beta peptide in brain endothelial cells. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2014; 1843:1150-61. [DOI: 10.1016/j.bbamcr.2014.02.016] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2013] [Revised: 02/20/2014] [Accepted: 02/23/2014] [Indexed: 11/25/2022]
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Nogalska A, D'Agostino C, Engel WK, Askanas V. Sodium phenylbutyrate reverses lysosomal dysfunction and decreases amyloid-β42 in an in vitro-model of inclusion-body myositis. Neurobiol Dis 2014; 65:93-101. [DOI: 10.1016/j.nbd.2014.01.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2013] [Revised: 01/08/2014] [Accepted: 01/14/2014] [Indexed: 01/19/2023] Open
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Rayavarapu S, Coley W, Van der Meulen JH, Cakir E, Tappeta K, Kinder TB, Dillingham BC, Brown KJ, Hathout Y, Nagaraju K. Activation of the ubiquitin proteasome pathway in a mouse model of inflammatory myopathy: a potential therapeutic target. ACTA ACUST UNITED AC 2014; 65:3248-58. [PMID: 24022788 DOI: 10.1002/art.38180] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2013] [Accepted: 08/27/2013] [Indexed: 01/01/2023]
Abstract
OBJECTIVE Myositis is characterized by severe muscle weakness. We and others have previously shown that endoplasmic reticulum (ER) stress plays a role in the pathogenesis of myositis. The present study was undertaken to identify perturbed pathways and assess their contribution to muscle disease in a mouse myositis model. METHODS Stable isotope labeling with amino acids in cell culture (SILAC) was used to identify alterations in the skeletal muscle proteome of myositic mice in vivo. Differentially altered protein levels identified in the initial comparisons were validated using a liquid chromatography tandem mass spectrometry spike-in strategy and further confirmed by immunoblotting. In addition, we evaluated the effect of a proteasome inhibitor, bortezomib, on the disease phenotype, using well-standardized functional, histologic, and biochemical assessments. RESULTS With the SILAC technique we identified significant alterations in levels of proteins belonging to the ER stress response, ubiquitin proteasome pathway (UPP), oxidative phosphorylation, glycolysis, cytoskeleton, and muscle contractile apparatus categories. We validated the myositis-related changes in the UPP and demonstrated a significant increase in the ubiquitination of muscle proteins as well as a specific increase in ubiquitin carboxyl-terminal hydrolase isozyme L1 (UCHL-1) in myositis, but not in muscle affected by other dystrophies or normal muscle. Inhibition of the UPP with bortezomib significantly improved muscle function and also significantly reduced tumor necrosis factor α expression in the skeletal muscle of mice with myositis. CONCLUSION Our findings indicate that ER stress activates downstream UPPs and contributes to muscle degeneration and that UCHL-1 is a potential biomarker for disease progression. UPP inhibition offers a potential therapeutic strategy for myositis.
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Affiliation(s)
- Sree Rayavarapu
- Children's National Medical Center and George Washington University, Washington DC
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Amaral PP, Dinger ME, Mattick JS. Non-coding RNAs in homeostasis, disease and stress responses: an evolutionary perspective. Brief Funct Genomics 2013; 12:254-78. [PMID: 23709461 DOI: 10.1093/bfgp/elt016] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Cells and organisms are subject to challenges and perturbations in their environment and physiology in all stages of life. The molecular response to such changes, including insulting conditions such as pathogen infections, involves coordinated modulation of gene expression programmes and has not only homeostatic but also ecological and evolutionary importance. Although attention has been primarily focused on signalling pathways and protein networks, non-coding RNAs (ncRNAs), which comprise a significant output of the genomes of prokaryotes and especially eukaryotes, are increasingly implicated in the molecular mechanisms of these responses. Long and short ncRNAs not only regulate development and cell physiology, they are also involved in disease states, including cancers, in host-pathogen interactions, and in a variety of stress responses. Indeed, regulatory RNAs are part of genetically encoded response networks and also underpin epigenetic processes, which are emerging as key mechanisms of adaptation and transgenerational inheritance. Here we present the growing evidence that ncRNAs are intrinsically involved in cellular and organismal adaptation processes, in both robustness and protection to stresses, as well as in mechanisms generating evolutionary change.
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Endres K, Reinhardt S. ER-stress in Alzheimer's disease: turning the scale? AMERICAN JOURNAL OF NEURODEGENERATIVE DISEASE 2013; 2:247-265. [PMID: 24319643 PMCID: PMC3852565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Accepted: 11/05/2013] [Indexed: 06/03/2023]
Abstract
Pathogenic mechanisms of Alzheimer's disease (AD) are intensely investigated as it is the most common form of dementia and burdens society by its costs and social demands. While key molecules such as A-beta peptides and tau have been identified decades ago, it is still enigmatic what drives the disease in its sporadic manifestation. Synthesis of A-beta peptides as well as phosphorylation of tau proteins comprise normal cellular functions and occur in principle in the healthy as well as in dementia-affected persons. Dyshomeostasis of Amyloid Precursor Protein (APP) cleavage, energy metabolism or kinase/phosphatase activity due to stressors has been suggested as a trigger of the disease. One way for cells to escape stress based on dysfunction of ER is the unfolded protein response - the UPR. This pathway is composed out of three different routes that differ in proteins involved, targets and consequences for cell fate: activation of transmembrane ER resident kinases IRE1-alpha and PERK or monomerization of membrane-anchored activating transcription factor 6 (ATF6) induce activation of versatile transcription factors (XBP-1, eIF2-alpha/ATF4 and ATF6 P50). These bind to specific DNA sequences on target gene promoters and on one hand attenuate general ER-prone protein synthesis and on the other equip the cell with tools to de-stress. If cells fail in stress compensation, this signaling also is able to evoke apoptosis. In this review we summarized knowledge on how APP processing and phosphorylation of tau might be influenced by ER-stress signaling. In addition, we depicted the effects UPR itself seems to have on molecules closely related to AD and describe what is known about UPR in AD animal models as well as in human patients.
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Affiliation(s)
- Kristina Endres
- Department of Psychiatry and Psychotherapy, Clinical Research Group, University Medical Centre Johannes Gutenberg-University Mainz Untere Zahlbacher Str. 8, D-55131 Mainz, Germany
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Qureshi IA, Mehler MF. Long non-coding RNAs: novel targets for nervous system disease diagnosis and therapy. Neurotherapeutics 2013; 10:632-46. [PMID: 23817781 PMCID: PMC3805860 DOI: 10.1007/s13311-013-0199-0] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The human genome encodes tens of thousands of long non-coding RNAs (lncRNAs), a novel and important class of genes. Our knowledge of lncRNAs has grown exponentially since their discovery within the last decade. lncRNAs are expressed in a highly cell- and tissue-specific manner, and are particularly abundant within the nervous system. lncRNAs are subject to post-transcriptional processing and inter- and intra-cellular transport. lncRNAs act via a spectrum of molecular mechanisms leveraging their ability to engage in both sequence-specific and conformational interactions with diverse partners (DNA, RNA, and proteins). Because of their size, lncRNAs act in a modular fashion, bringing different macromolecules together within the three-dimensional context of the cell. lncRNAs thus coordinate the execution of transcriptional, post-transcriptional, and epigenetic processes and critical biological programs (growth and development, establishment of cell identity, and deployment of stress responses). Emerging data reveal that lncRNAs play vital roles in mediating the developmental complexity, cellular diversity, and activity-dependent plasticity that are hallmarks of brain. Corresponding studies implicate these factors in brain aging and the pathophysiology of brain disorders, through evolving paradigms including the following: (i) genetic variation in lncRNA genes causes disease and influences susceptibility; (ii) epigenetic deregulation of lncRNAs genes is associated with disease; (iii) genomic context links lncRNA genes to disease genes and pathways; and (iv) lncRNAs are otherwise interconnected with known pathogenic mechanisms. Hence, lncRNAs represent prime targets that can be exploited for diagnosing and treating nervous system diseases. Such clinical applications are in the early stages of development but are rapidly advancing because of existing expertise and technology platforms that are readily adaptable for these purposes.
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Affiliation(s)
- Irfan A. Qureshi
- />Roslyn and Leslie Goldstein Laboratory for Stem Cell Biology and Regenerative Medicine, Albert Einstein College of Medicine, Bronx, New York USA
- />Institute for Brain Disorders and Neural Regeneration, Albert Einstein College of Medicine, Bronx, New York USA
- />Department of Neurology, Albert Einstein College of Medicine, Bronx, New York USA
- />Rose F. Kennedy Center for Research on Intellectual and Developmental Disabilities, Albert Einstein College of Medicine, 1410 Pelham Parkway South, Room 401, Bronx, New York 10461 USA
| | - Mark F. Mehler
- />Roslyn and Leslie Goldstein Laboratory for Stem Cell Biology and Regenerative Medicine, Albert Einstein College of Medicine, Bronx, New York USA
- />Institute for Brain Disorders and Neural Regeneration, Albert Einstein College of Medicine, Bronx, New York USA
- />Department of Neurology, Albert Einstein College of Medicine, Bronx, New York USA
- />Department of Neuroscience, Albert Einstein College of Medicine, Bronx, New York USA
- />Department of Psychiatry and Behavioral Sciences, Albert Einstein College of Medicine, Bronx, New York USA
- />Rose F. Kennedy Center for Research on Intellectual and Developmental Disabilities, Albert Einstein College of Medicine, 1410 Pelham Parkway South, Room 401, Bronx, New York 10461 USA
- />Einstein Cancer Center, Albert Einstein College of Medicine, Bronx, New York USA
- />Ruth L. and David S. Gottesman Institute for Stem Cell Biology and Regenerative Medicine, Albert Einstein College of Medicine, Bronx, New York USA
- />Center for Epigenomics, Albert Einstein College of Medicine, Bronx, New York USA
- />Institute for Aging Research, Albert Einstein College of Medicine, Bronx, New York USA
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Shi X, Sun M, Liu H, Yao Y, Song Y. Long non-coding RNAs: a new frontier in the study of human diseases. Cancer Lett 2013; 339:159-66. [PMID: 23791884 DOI: 10.1016/j.canlet.2013.06.013] [Citation(s) in RCA: 929] [Impact Index Per Article: 84.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2013] [Revised: 06/05/2013] [Accepted: 06/08/2013] [Indexed: 02/07/2023]
Abstract
With the development of whole genome and transcriptome sequencing technologies, long noncoding RNAs (lncRNAs) have received increased attention. Multiple studies indicate that lncRNAs act not only as the intermediary between DNA and protein but also as important protagonists of cellular functions. LncRNAs can regulate gene expression in many ways, including chromosome remodeling, transcription and post-transcriptional processing. Moreover, the dysregulation of lncRNAs has increasingly been linked to many human diseases, especially in cancers. Here, we reviewed the rapidly advancing field of lncRNAs and described the relationship between the dysregulation of lncRNAs and human diseases, highlighting the specific roles of lncRNAs in human diseases.
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Affiliation(s)
- Xuefei Shi
- Department of Respiratory Medicine, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China.
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Pathogenic considerations in sporadic inclusion-body myositis, a degenerative muscle disease associated with aging and abnormalities of myoproteostasis. J Neuropathol Exp Neurol 2012; 71:680-93. [PMID: 22805774 DOI: 10.1097/nen.0b013e31826183c8] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The pathogenesis of sporadic inclusion-body myositis (s-IBM) is complex; it involves multidimensional pathways and the most critical issues are still unresolved. The onset of muscle fiber damage is age related and the disease is slowly, but inexorably, progressive. Muscle fiber degeneration and mononuclear cell inflammation are major components of s-IBM pathology, but which is precedent and how they interrelate is not known. There is growing evidence that aging of the muscle fiber associated with intramyofiber accumulation of conformationally modified proteins plays a primary pathogenic role leading to muscle fiber destruction. Here, we review the presumably most important known molecular abnormalities that occur in s-IBM myofibers and that likely contribute to s-IBM pathogenesis. Abnormal accumulation within the fibers of multiprotein aggregates (several of which are congophilic and, therefore, generically called "amyloid") may result from increased transcription of several proteins, their abnormal posttranslational modifications and misfolding, and inadequate protein disposal, that is, abnormal "myoproteostasis," which is combined with and may be provoked or abetted by an aging intracellular milieu. The potential cytotoxicity of accumulated amyloid β protein (Aβ42) and its oligomers, phosphorylated tau in the form of paired helical filaments and α-synuclein, and the putative pathogenic role and cause of the mitochondrial abnormalities and oxidative stress are reviewed. On the basis of our experimental evidence, potential interventions in the complex, interwoven pathogenic cascade of s-IBM are suggested.
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Abstract
Our appreciation of the role of endoplasmic reticulum (ER) stress pathways in both skeletal muscle homeostasis and the progression of muscle diseases is gaining momentum. This review provides insight into ER stress mechanisms during physiologic and pathological disturbances in skeletal muscle. The role of ER stress in the response to dietary alterations and acute stressors, including its role in autoimmune and genetic muscle disorders, has been described. Recent studies identifying ER stress markers in diseased skeletal muscle are noted. The emerging evidence for ER-mitochondrial interplay in skeletal muscle and its importance during chronic ER stress in activation of both inflammatory and cell death pathways (autophagy, necrosis, and apoptosis) have been discussed. Thus, understanding the ER stress-related molecular pathways underlying physiologic and pathological phenotypes in healthy and diseased skeletal muscle should lead to novel therapeutic targets for muscle disease.
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Nogalska A, D'Agostino C, Engel WK, Askanas V. Activation of the γ-secretase complex and presence of γ-secretase-activating protein may contribute to Aβ42 production in sporadic inclusion-body myositis muscle fibers. Neurobiol Dis 2012; 48:141-9. [PMID: 22750528 DOI: 10.1016/j.nbd.2012.06.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2012] [Revised: 05/22/2012] [Accepted: 06/22/2012] [Indexed: 01/07/2023] Open
Abstract
The muscle-fiber phenotype of sporadic inclusion-body myositis (s-IBM), the most common muscle disease associated with aging, shares several pathological abnormalities with Alzheimer disease (AD) brain, including accumulation of amyloid-β 42 (Aβ42) and its cytotoxic oligomers. The exact mechanisms leading to Aβ42 production within s-IBM muscle fibers are not known. Aβ42 and Aβ40 are generated after the amyloid-precursor protein (AβPP) is cleaved by β-secretase and the γ-secretase complex. Aβ42 is considered more cytotoxic than Aβ40, and it has a higher propensity to oligomerize, form amyloid fibrils, and aggregate. Recently, we have demonstrated in cultured human muscle fibers that experimental inhibition of lysosomal enzyme activities leads to Aβ42 oligomerization. In s-IBM muscle, we here demonstrate prominent abnormalities of the γ-secretase complex, as evidenced by: a) increase of γ-secretase components, namely active presenilin 1, presenilin enhancer 2, nicastrin, and presence of its mature, glycosylated form; b) increase of mRNAs of these γ-secretase components; c) increase of γ-secretase activity; d) presence of an active form of a newly-discovered γ-secretase activating protein (GSAP); and e) increase of GSAP mRNA. Furthermore, we demonstrate that experimental inhibition of lysosomal autophagic enzymes in cultured human muscle fibers a) activates γ-secretase, and b) leads to posttranslational modifications of AβPP and increase of Aβ42. Since autophagy is impaired in biopsied s-IBM muscle, the same mechanism might be responsible for its having increased γ-secretase activity and Aβ42 production. Accordingly, improving lysosomal function might be a therapeutic strategy for s-IBM patients.
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Affiliation(s)
- Anna Nogalska
- USC Neuromuscular Center, Department of Neurology, University of Southern California Keck School of Medicine, Good Samaritan Hospital, Los Angeles, CA 90017‐1912, USA
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Abstract
Neurological disease, and in particular neurodegenerative diseases, cause significant burdens on both patient and healthcare costs. Despite extensive research, treatment options for patients with these conditions remain limited, and generally, only provide modest symptomatic relief. Aberrant epigenetic post-translational modifications of proteins are emerging as important elements in the pathogenesis of neurological disease. Using Alzheimer’s disease and Huntington’s disease as examples in the following article, some of latest data linking both the histone code and the various proteins that regulate this code to the pathogenesis of neurological disease are discussed. The current evidence suggesting that pharmacologically targeting one such family, the histone deacetylases, may be of potential benefit in the treatment of such diseases is also discussed. Finally, some of the potential mechanisms to specifically target these proteins within the neurological setting are discussed.
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Affiliation(s)
- Steven G Gray
- Translational Cancer Research Group, Department of Clinical Medicine, Institute of Molecular Medicine, Trinity Centre for Health Sciences, St James’s Hospital, James’s Street, Dublin 8, Ireland
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