1
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Arrigo AP. Mammalian HspB1 (Hsp27) is a molecular sensor linked to the physiology and environment of the cell. Cell Stress Chaperones 2017; 22:517-529. [PMID: 28144778 PMCID: PMC5465029 DOI: 10.1007/s12192-017-0765-1] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Revised: 01/11/2017] [Accepted: 01/14/2017] [Indexed: 12/11/2022] Open
Abstract
Constitutively expressed small heat shock protein HspB1 regulates many fundamental cellular processes and plays major roles in many human pathological diseases. In that regard, this chaperone has a huge number of apparently unrelated functions that appear linked to its ability to recognize many client polypeptides that are subsequently modified in their activity and/or half-life. A major parameter to understand how HspB1 is dedicated to interact with particular clients in defined cellular conditions relates to its complex oligomerization and phosphorylation properties. Indeed, HspB1 structural organization displays dynamic and complex rearrangements in response to changes in the cellular environment or when the cell physiology is modified. These structural modifications probably reflect the formation of structural platforms aimed at recognizing specific client polypeptides. Here, I have reviewed data from the literature and re-analyzed my own studies to describe and discuss these fascinating changes in HspB1 structural organization.
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Affiliation(s)
- André-Patrick Arrigo
- Apoptosis, Cancer and Development Laboratory, Lyon Cancer Research Center, INSERM U1052-CNRS UMR5286, Centre Léon Bérard, 28 rue Laennec, Lyon, 69008, France.
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2
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Using bicistronic constructs to evaluate the chaperone activities of heat shock proteins in cells. Sci Rep 2017; 7:2387. [PMID: 28539657 PMCID: PMC5443837 DOI: 10.1038/s41598-017-02459-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Accepted: 04/12/2017] [Indexed: 01/03/2023] Open
Abstract
Heat shock proteins (Hsps) are molecular chaperones that prevent the aggregation of client proteins by facilitating their refolding, or trafficking them for degradation. The chaperone activities of Hsps are dependent on dynamic protein-protein interactions, including their oligomerisation into large multi-subunit complexes. Thus, tagging Hsps with fluorescent proteins can interfere with their chaperone activity. To overcome this limitation, we have exploited bicistronic constructs for the concurrent expression of a non-tagged Hsp and fluorescent reporter from a single mRNA in cells. We used the Hsp-encoding bicistronic constructs in a cell-based model of protein aggregation, using a destabilised (mutant) form of firefly luciferase (mFluc) that forms inclusion bodies in cells. Expression of Hsp40, Hsp70, or Hsp40 and Hsp70 in cells expressing mFluc decreased the formation of inclusion bodies by 25–46% compared to controls. Moreover, there was a concentration-dependent decrease in the proportion of cells with inclusions when Hsp70, or Hsp40 and Hsp70 were co-expressed with mFluc in cells. The Hsp-encoding bicistronic constructs enable transfection efficiencies and concentration-dependent effects of Hsp expression to be determined using fluorescence based techniques, without the need to tag the Hsp with a fluorescent protein.
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3
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Yue F, Li W, Zou J, Chen Q, Xu G, Huang H, Xu Z, Zhang S, Gallinari P, Wang F, McKeehan WL, Liu L. Blocking the association of HDAC4 with MAP1S accelerates autophagy clearance of mutant Huntingtin. Aging (Albany NY) 2016; 7:839-53. [PMID: 26540094 PMCID: PMC4637209 DOI: 10.18632/aging.100818] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Autophagy controls and executes the turnover of abnormally aggregated proteins. MAP1S interacts with the autophagy marker LC3 and positively regulates autophagy flux. HDAC4 associates with the aggregation-prone mutant huntingtin protein (mHTT) that causes Huntington's disease, and colocalizes with it in cytosolic inclusions. It was suggested HDAC4 interacts with MAP1S in a yeast two-hybrid screening. Here, we found that MAP1S interacts with HDAC4 via a HDAC4-binding domain (HBD). HDAC4 destabilizes MAP1S, suppresses autophagy flux and promotes the accumulation of mHTT aggregates. This occurs by an increase in the deacetylation of the acetylated MAP1S. Either suppression of HDAC4 with siRNA or overexpression of the MAP1S HBD leads to stabilization of MAP1S, activation of autophagy flux and clearance of mHTT aggregates. Therefore, specific interruption of the HDAC4-MAP1S interaction with short peptides or small molecules to enhance autophagy flux may relieve the toxicity of mHTT associated with Huntington's disease and improve symptoms of HD patients.
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Affiliation(s)
- Fei Yue
- Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, TX 77030, USA
| | - Wenjiao Li
- Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, TX 77030, USA
| | - Jing Zou
- Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, TX 77030, USA
| | - Qi Chen
- Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, TX 77030, USA
| | - Guibin Xu
- Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, TX 77030, USA.,Department of Urology, The Fifth Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong Province, China
| | - Hai Huang
- Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, TX 77030, USA.,Department of Urology, The Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Zhen Xu
- The Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases, The University of Texas Health, Science Center at Houston, Houston, TX 77030, USA
| | - Sheng Zhang
- The Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases, The University of Texas Health, Science Center at Houston, Houston, TX 77030, USA
| | | | - Fen Wang
- Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, TX 77030, USA
| | - Wallace L McKeehan
- Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, TX 77030, USA
| | - Leyuan Liu
- Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, TX 77030, USA.,Department of Molecular and Cellular Medicine, College of Medicine, Texas A&M Health Science Center, TX 77843, USA
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4
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Chakraborty J, Rajamma U, Jana N, Mohanakumar K. Quercetin improves the activity of the ubiquitin-proteasomal system in 150Q mutated huntingtin-expressing cells but exerts detrimental effects on neuronal survivability. J Neurosci Res 2015; 93:1581-91. [DOI: 10.1002/jnr.23618] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2014] [Revised: 06/02/2015] [Accepted: 06/19/2015] [Indexed: 12/20/2022]
Affiliation(s)
- J. Chakraborty
- Division of Cell Biology and Physiology; Laboratory of Clinical and Experimental Neuroscience, CSIR-Indian Institute of Chemical Biology; Kolkata India
| | - U. Rajamma
- Manovikas Biomedical Research and Diagnostic Centre; Kolkata India
| | - N. Jana
- National Brain Research Centre; Gurgaon Haryana India
| | - K.P. Mohanakumar
- Division of Cell Biology and Physiology; Laboratory of Clinical and Experimental Neuroscience, CSIR-Indian Institute of Chemical Biology; Kolkata India
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5
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Arrigo AP, Ducarouge B, Lavial F, Gibert B. Immense Cellular Implications Associated to Small Stress Proteins Expression: Impacts on Human Pathologies. HEAT SHOCK PROTEINS 2015. [DOI: 10.1007/978-3-319-16077-1_2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Xiao L, Li H, Zhang J, Yang F, Huang A, Deng J, Liang M, Ma F, Hu M, Huang Z. Salidroside protects Caenorhabditis elegans neurons from polyglutamine-mediated toxicity by reducing oxidative stress. Molecules 2014; 19:7757-69. [PMID: 24918543 PMCID: PMC6270757 DOI: 10.3390/molecules19067757] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2014] [Revised: 05/30/2014] [Accepted: 06/05/2014] [Indexed: 01/24/2023] Open
Abstract
Polyglutamine (polyQ) aggregation plays a pivotal role in the pathological process of Huntington's disease and other polyQ disorders. Therefore, strategies aiming at restoring dysfunction and reducing stresses mediated by polyQ toxicity are of therapeutic interest for proteotoxicity diseases. Salidroside, a glycoside from Rhodiola rosea, has been shown to have a variety of bioactivities, including antioxidant activity. Using transgenic Caenorhabditis elegans models, we show here that salidroside is able to reduce neuronal death and behavioral dysfunction mediated by polyQ expressed in ASH neurons, but the neuroprotective effect is not associated with prevention of polyQ aggregation per se. Further experiments reveal that the neuroprotective effect of salidroside in C. elegans models involves its antioxidant capabilities, including decrease of ROS levels and paraquat-induced mortality, increase of antioxidant enzyme activities and reduction of lipid peroxidation. These results demonstrate that salidroside exerts its neuroprotective function against polyQ toxicity via oxidative stress pathways.
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Affiliation(s)
- Lingyun Xiao
- School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China.
| | - Haifeng Li
- School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China.
| | - Ju Zhang
- School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China.
| | - Fan Yang
- School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China.
| | - Aizhen Huang
- Guangdong Province Key Laboratory for Biotechnology Drug Candidates, School of Biosciences and Biopharmaceutics, Guangdong Pharmaceutical University, Guangzhou 510006, China.
| | - Jingjing Deng
- School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China.
| | - Ming Liang
- Research & Development Centre, Infinitus (China) Company Ltd, Guangzhou 510665, China.
| | - Fangli Ma
- Research & Development Centre, Infinitus (China) Company Ltd, Guangzhou 510665, China.
| | - Minghua Hu
- Research & Development Centre, Infinitus (China) Company Ltd, Guangzhou 510665, China.
| | - Zebo Huang
- School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China.
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7
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Arrigo AP, Gibert B. HspB1, HspB5 and HspB4 in Human Cancers: Potent Oncogenic Role of Some of Their Client Proteins. Cancers (Basel) 2014; 6:333-65. [PMID: 24514166 PMCID: PMC3980596 DOI: 10.3390/cancers6010333] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2013] [Revised: 01/03/2014] [Accepted: 01/17/2014] [Indexed: 12/20/2022] Open
Abstract
Human small heat shock proteins are molecular chaperones that regulate fundamental cellular processes in normal unstressed cells as well as in many cancer cells where they are over-expressed. These proteins are characterized by cell physiology dependent changes in their oligomerization and phosphorylation status. These structural changes allow them to interact with many different client proteins that subsequently display modified activity and/or half-life. Nowdays, the protein interactomes of small Hsps are under intense investigations and will represent, when completed, key parameters to elaborate therapeutic strategies aimed at modulating the functions of these chaperones. Here, we have analyzed the potential pro-cancerous roles of several client proteins that have been described so far to interact with HspB1 (Hsp27) and its close members HspB5 (αB-crystallin) and HspB4 (αA-crystallin).
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Affiliation(s)
- André-Patrick Arrigo
- Apoptosis, Cancer and Development Laboratory, Lyon Cancer Research Center, INSERM U1052-CNRS UMR5286, Claude Bernard University Lyon 1, Lyon 69008, France.
| | - Benjamin Gibert
- Apoptosis, Cancer and Development Laboratory, Lyon Cancer Research Center, INSERM U1052-CNRS UMR5286, Claude Bernard University Lyon 1, Lyon 69008, France.
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8
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Huntington's disease induced cardiac amyloidosis is reversed by modulating protein folding and oxidative stress pathways in the Drosophila heart. PLoS Genet 2013; 9:e1004024. [PMID: 24367279 PMCID: PMC3868535 DOI: 10.1371/journal.pgen.1004024] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2013] [Accepted: 10/29/2013] [Indexed: 11/19/2022] Open
Abstract
Amyloid-like inclusions have been associated with Huntington's disease (HD), which is caused by expanded polyglutamine repeats in the Huntingtin protein. HD patients exhibit a high incidence of cardiovascular events, presumably as a result of accumulation of toxic amyloid-like inclusions. We have generated a Drosophila model of cardiac amyloidosis that exhibits accumulation of PolyQ aggregates and oxidative stress in myocardial cells, upon heart-specific expression of Huntingtin protein fragments (Htt-PolyQ) with disease-causing poly-glutamine repeats (PolyQ-46, PolyQ-72, and PolyQ-102). Cardiac expression of GFP-tagged Htt-PolyQs resulted in PolyQ length-dependent functional defects that included increased incidence of arrhythmias and extreme cardiac dilation, accompanied by a significant decrease in contractility. Structural and ultrastructural analysis of the myocardial cells revealed reduced myofibrillar content, myofibrillar disorganization, mitochondrial defects and the presence of PolyQ-GFP positive aggregates. Cardiac-specific expression of disease causing Poly-Q also shortens lifespan of flies dramatically. To further confirm the involvement of oxidative stress or protein unfolding and to understand the mechanism of PolyQ induced cardiomyopathy, we co-expressed expanded PolyQ-72 with the antioxidant superoxide dismutase (SOD) or the myosin chaperone UNC-45. Co-expression of SOD suppressed PolyQ-72 induced mitochondrial defects and partially suppressed aggregation as well as myofibrillar disorganization. However, co-expression of UNC-45 dramatically suppressed PolyQ-72 induced aggregation and partially suppressed myofibrillar disorganization. Moreover, co-expression of both UNC-45 and SOD more efficiently suppressed GFP-positive aggregates, myofibrillar disorganization and physiological cardiac defects induced by PolyQ-72 than did either treatment alone. Our results demonstrate that mutant-PolyQ induces aggregates, disrupts the sarcomeric organization of contractile proteins, leads to mitochondrial dysfunction and increases oxidative stress in cardiomyocytes leading to abnormal cardiac function. We conclude that modulation of both protein unfolding and oxidative stress pathways in the Drosophila heart model can ameliorate the detrimental PolyQ effects, thus providing unique insights into the genetic mechanisms underlying amyloid-induced cardiac failure in HD patients. Huntington's disease (HD) is associated with amyloid-like inclusions in the brain and heart, and accumulation of amyloid protein is associated with neurodegeneration and cardiomyopathy. Recent studies suggest that HD patients show increased susceptibility to cardiac failure. However, the mechanisms by which disease-causing poly-glutamine repeats (PolyQ) cause heart dysfunction in these patients are unclear. We have developed a novel Drosophila heart model that exhibits significant GFP-positive aggregates upon HD-causing PolyQ expression in myocardial cells resulting in PolyQ length-dependent physiological defects. Modulation of protein folding and oxidative stress pathways in this system reduced the number of aggregates and reversed the cardiac dysfunction in response to expression of disease-causing PolyQ. The ability to explore PolyQ-associated mechanisms of cardiomyopathy in a genetically tractable whole organism, Drosophila melanogaster, promises to provide novel insights into the relationship between amyloid accumulation and heart dysfunction. Our findings not only impact the understanding of PolyQ-induced cardiomyopathy but also other human cardiac diseases associated with oxidative stress, mitochondrial defects and protein homeostasis.
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9
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Haun F, Nakamura T, Shiu AD, Cho DH, Tsunemi T, Holland EA, La Spada AR, Lipton SA. S-nitrosylation of dynamin-related protein 1 mediates mutant huntingtin-induced mitochondrial fragmentation and neuronal injury in Huntington's disease. Antioxid Redox Signal 2013; 19:1173-84. [PMID: 23641925 PMCID: PMC3785802 DOI: 10.1089/ars.2012.4928] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
AIMS Dynamin-related protein1 (Drp1) is a large GTPase that mediates mitochondrial fission. We recently reported in Alzheimer's disease (AD) that S-nitrosylation of Drp1 (forming S-nitroso [SNO]-Drp1) results in GTPase hyperactivity and mitochondrial fragmentation, thus impairing bioenergetics and inducing synaptic damage and neuronal loss. Here, since aberrant mitochondrial dynamics are also key features of Huntington's disease (HD), we investigated whether formation of SNO-Drp1 contributes to the pathogenesis of HD in cell-based and animal models. RESULTS We found that expression of mutant huntingtin (mutHTT) protein in primary cultured neurons triggers significant production of nitric oxide (NO). Consistent with this result, increased levels of SNO-Drp1 were found in the striatum of a transgenic mouse model of HD as well as in human postmortem brains from HD patients. Using specific fluorescence markers, we found that formation of SNO-Drp1 induced excessive mitochondrial fragmentation followed by loss of dendritic spines, signifying synaptic damage. These neurotoxic events were significantly abrogated after transfection with non-nitrosylatable mutant Drp1(C644A), or by the blocking of NO production using an nitric oxide synthase inhibitor. These findings suggest that SNO-Drp1 is a key mediator of mutHTT toxicity, and, thus, may represent a novel drug target for HD. INNOVATION AND CONCLUSION Our findings indicate that aberrant S-nitrosylation of Drp1 is a prominent pathological feature of neurodegenerative diseases such as AD and HD. Moreover, the SNO-Drp1 signaling pathway links mutHTT neurotoxicity to a malfunction in mitochondrial dynamics, resulting in neuronal synaptic damage in HD.
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Affiliation(s)
- Florian Haun
- 1 Sanford-Burnham Medical Research Institute , Del E. Webb Center for Neuroscience, Aging, and Stem Cell Research, La Jolla, California
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10
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Ayala-Peña S. Role of oxidative DNA damage in mitochondrial dysfunction and Huntington's disease pathogenesis. Free Radic Biol Med 2013; 62:102-110. [PMID: 23602907 PMCID: PMC3722255 DOI: 10.1016/j.freeradbiomed.2013.04.017] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/06/2012] [Revised: 02/21/2013] [Accepted: 04/12/2013] [Indexed: 12/20/2022]
Abstract
Huntington's disease (HD) is a neurodegenerative disorder with an autosomal dominant expression pattern and typically a late-onset appearance. HD is a movement disorder with a heterogeneous phenotype characterized by involuntary dance-like gait, bioenergetic deficits, motor impairment, and cognitive and psychiatric deficits. Compelling evidence suggests that increased oxidative stress and mitochondrial dysfunction may underlie HD pathogenesis. However, the exact mechanisms underlying mutant huntingtin-induced neurological toxicity remain unclear. The objective of this paper is to review recent literature regarding the role of oxidative DNA damage in mitochondrial dysfunction and HD pathogenesis.
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Affiliation(s)
- Sylvette Ayala-Peña
- Department of Pharmacology and Toxicology, University of Puerto Rico Medical Sciences Campus, P.O. Box 365067, San Juan, Puerto Rico 00936-5067.
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11
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Arrigo AP. Pathology-dependent effects linked to small heat shock proteins expression: an update. SCIENTIFICA 2012; 2012:185641. [PMID: 24278676 PMCID: PMC3820616 DOI: 10.6064/2012/185641] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/13/2012] [Accepted: 09/17/2012] [Indexed: 06/02/2023]
Abstract
Small heat shock proteins (small Hsps) are stress-induced molecular chaperones that act as holdases towards polypeptides that have lost their folding in stress conditions or consequently of mutations in their coding sequence. A cellular protection against the deleterious effects mediated by damaged proteins is thus provided to cells. These chaperones are also highly expressed in response to protein conformational and inflammatory diseases and cancer pathologies. Through specific and reversible modifications in their phospho-oligomeric organization, small Hsps can chaperone appropriate client proteins in order to provide cells with resistance to different types of injuries or pathological conditions. By helping cells to better cope with their pathological status, their expression can be either beneficial, such as in diseases characterized by pathological cell degeneration, or deleterious when they are required for tumor cell survival. Moreover, small Hsps are actively released by cells and can act as immunogenic molecules that have dual effects depending on the pathology. The cellular consequences linked to their expression levels and relationships with other Hsps as well as therapeutic strategies are discussed in view of their dynamic structural organization required to interact with specific client polypeptides.
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Affiliation(s)
- A.-P. Arrigo
- Apoptosis Cancer and Development Laboratory, Lyon Cancer Research Center, INSERM U1052-CNRS UMR5286, Centre Léon Bérard, Claude Bernard University Lyon1, 28 Rue Laennec, 69008 Lyon, France
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12
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Cherneva RV, Georgiev OB, Petrova DS, Trifonova NL, Stamenova M, Ivanova V, Vlasov VI. The role of small heat-shock protein αB-crystalline (HspB5) in COPD pathogenesis. Int J Chron Obstruct Pulmon Dis 2012; 7:633-40. [PMID: 23055712 PMCID: PMC3468058 DOI: 10.2147/copd.s34929] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Background αB-crystallin (HspB5) is a chaperone whose role as a marker of innate immunity activation as well as its therapeutic potential have recently been investigated in several inflammatory diseases: multiple sclerosis, myocardial ischemia, and Guillain–Barré syndrome. Aim The aim of this study is to determine the role of αB-crystallin in chronic obstructive pulmonary disease (COPD) pathogenesis and inflammation. Materials Plasma levels of αB-crystallin were studied in 163 patients: 52 healthy non-COPD smokers; 20 COPD smokers in Global Initiative for Chronic Obstructive Lung Disease (GOLD) stages I–II; 43 COPD smokers in GOLD stages III-IV. Forty-eight patients were diagnosed with acute inflammatory respiratory disease. The plasma levels of αB-crystallin antibodies were determined by an enzyme-linked immunosorbent assay (Calbiochem), and were confirmed with Western blotting. Tissue expression of the protein was compared in three different groups of patients: COPD smokers, COPD nonsmokers, and in patients with age-related emphysema. Results The mean level of anti-αB-crystallin antibodies in non-COPD smokers was 0.291nm. In COPD smokers it was 0.352 nm and, in patients with inflammatory lung diseases, 0.433 nm. There was a statistically significant difference between COPD smokers and healthy non-COPD smokers (P = 0.010). The same could be observed comparing the group of patients with acute inflammation and non-COPD healthy smokers (P = 0.007). There was no statistically significant difference between patients with mild/moderate inflammation and those with severe COPD. Tissue detection of the protein showed that it was significantly overexpressed in COPD smokers in comparison to COPD nonsmokers and was only slightly expressed in patients with age-related emphysema. Conclusion αB-crystallin is increased in patients with inflammatory lung diseases. Though unspecific, it could be used in a panel of markers discerning COPD smokers from healthy nonsmokers. As αB-crystallin is a regulator of innate immunity and a therapeutic anti-inflammatory agent, its exact role in COPD pathogenesis and therapy should be explored further.
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Affiliation(s)
- Radostina V Cherneva
- Clinic of Internal Medicine, Division of Pulmonology, University Hospital Alexandrovska, Sofia, Bulgaria.
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Pitts A, Dailey K, Newington JT, Chien A, Arseneault R, Cann T, Thompson LM, Cumming RC. Dithiol-based compounds maintain expression of antioxidant protein peroxiredoxin 1 that counteracts toxicity of mutant huntingtin. J Biol Chem 2012; 287:22717-29. [PMID: 22577145 DOI: 10.1074/jbc.m111.334565] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Mitochondrial dysfunction and elevated reactive oxygen species are strongly implicated in both aging and various neurodegenerative disorders, including Huntington disease (HD). Because reactive oxygen species can promote the selective oxidation of protein cysteine sulfhydryl groups to disulfide bonds we examined the spectrum of disulfide-bonded proteins that were specifically altered in a HD context. Protein extracts from PC12 cells overexpressing the amino-terminal fragment of the Huntingtin (Htt) protein with either a nonpathogenic or pathogenic polyglutamine repeat (Htt-103Q) were resolved by redox two-dimensional PAGE followed by mass spectrometry analysis. Several antioxidant proteins were identified that exhibited changes in disulfide bonding unique to Htt-103Q expressing cells. In particular, the antioxidant protein peroxiredoxin 1 (Prx1) exhibited both decreased expression and hyperoxidation in response to mutant Htt expressed in either PC12 cells or immortalized striatal cells exposed to 3-nitropropionic acid. Ectopic expression of Prx1 in PC12 cells attenuated mutant Htt-induced toxicity. In contrast, short hairpin RNA-mediated knockdown of Prx1 potentiated mHtt toxicity. Furthermore, treatment with the dithiol-based compounds dimercaptopropanol and dimercaptosuccinic acid suppressed toxicity in both HD cell models, whereas monothiol compounds were relatively ineffective. Dimercaptopropanol treatment also prevented mutant Htt-induced loss of Prx1 expression in both cell models. Our studies reveal for the first time that pathogenic Htt can affect the expression and redox state of antioxidant proteins; an event countered by specific dithiol-based compounds. These findings should provide a catalyst to explore the use of dithiol-based drugs for the treatment of neurodegenerative diseases.
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Affiliation(s)
- Andrea Pitts
- Department of Biology, University of Western Ontario, London, Ontario N6A 5B7, Canada
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Abstract
Patients with Huntington's disease suffer severe neuronal loss and signs of oxidative damage in the brain. Previously we found that primary neurons from embryonic cortex of mice bearing the Huntington's disease mutation (140 glutamines inserted into exon 1 of huntingtin) showed higher levels of reactive oxygen species before cell death. Here, we treated mutant neurons with known neuroprotective agents and determined the effects on neuronal survival and levels of reactive oxygen species. Primary neurons were exposed to the neurotrophin, brain derived neurotrophic factor, the antioxidant N-acetyl-cysteine or a specific inhibitor of glycogen synthase kinase 3-β, SB216763. Each reagent increased the survival of the mutant neurons compared with untreated mutant neurons and also reduced the levels of reactive oxygen species to levels of wild-type neurons. These results suggest that reducing the levels of reactive oxygen species may be necessary to protect neurons with the Huntington's disease mutation from cell death.
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Hands S, Sajjad MU, Newton MJ, Wyttenbach A. In vitro and in vivo aggregation of a fragment of huntingtin protein directly causes free radical production. J Biol Chem 2011; 286:44512-20. [PMID: 21984825 DOI: 10.1074/jbc.m111.307587] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Neurodegenerative diseases are characterized by intra- and/or extracellular protein aggregation and oxidative stress. Intense attention has been paid to whether protein aggregation itself contributes to abnormal production of free radicals and ensuing cellular oxidative damage. Although this question has been investigated in the context of extracellular protein aggregation, it remains unclear whether protein aggregation inside cells alters the redox homeostasis. To address this, we have used in vitro and in vivo (cellular) models of Huntington disease, one of nine polyglutamine (poly(Q)) disorders, and examined the causal relationship among intracellular protein aggregation, reactive oxygen species (ROS) production, and toxicity. Live imaging of cells expressing a fragment of huntingtin (httExon1) with a poly(Q) expansion shows increased ROS production preceding cell death. ROS production is poly(Q) length-dependent and not due to the httExon 1 flanking sequence. Aggregation inhibition by the MW7 intrabody and Pgl-135 treatment abolishes ROS production, showing that increased ROS is caused by poly(Q) aggregation itself. To examine this hypothesis further, we determined whether aggregation of poly(Q) peptides in vitro generated free radicals. Monitoring poly(Q) protein aggregation using atomic force microscopy and hydrogen peroxide (H(2)O(2)) production over time in parallel we show that oligomerization of httEx1Q53 results in early generation of H(2)O(2). Inhibition of poly(Q) oligomerization by the single chain antibody MW7 abrogates H(2)O(2) formation. These results demonstrate that intracellular protein aggregation directly causes free radical production, and targeting potentially toxic poly(Q) oligomers may constitute a therapeutic target to counteract oxidative stress in poly(Q) diseases.
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Affiliation(s)
- Sarah Hands
- Southampton Neuroscience Group, School of Biological Sciences, University of Southampton, Southampton SO17 1BJ, United Kingdom
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16
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Xiong Y, Uys JD, Tew KD, Townsend DM. S-glutathionylation: from molecular mechanisms to health outcomes. Antioxid Redox Signal 2011; 15:233-70. [PMID: 21235352 PMCID: PMC3110090 DOI: 10.1089/ars.2010.3540] [Citation(s) in RCA: 220] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Redox homeostasis governs a number of critical cellular processes. In turn, imbalances in pathways that control oxidative and reductive conditions have been linked to a number of human disease pathologies, particularly those associated with aging. Reduced glutathione is the most prevalent biological thiol and plays a crucial role in maintaining a reduced intracellular environment. Exposure to reactive oxygen or nitrogen species is causatively linked to the disease pathologies associated with redox imbalance. In particular, reactive oxygen species can differentially oxidize certain cysteine residues in target proteins and the reversible process of S-glutathionylation may mitigate or mediate the damage. This post-translational modification adds a tripeptide and a net negative charge that can lead to distinct structural and functional changes in the target protein. Because it is reversible, S-glutathionylation has the potential to act as a biological switch and to be integral in a number of critical oxidative signaling events. The present review provides a comprehensive account of how the S-glutathionylation cycle influences protein structure/function and cellular regulatory events, and how these may impact on human diseases. By understanding the components of this cycle, there should be opportunities to intervene in stress- and aging-related pathologies, perhaps through prevention and diagnostic and therapeutic platforms.
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Affiliation(s)
- Ying Xiong
- Department of Pharmaceutical Sciences, Medical University of South Carolina, Charleston, 29425, USA
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Zhang H, Rajasekaran NS, Orosz A, Xiao X, Rechsteiner M, Benjamin IJ. Selective degradation of aggregate-prone CryAB mutants by HSPB1 is mediated by ubiquitin-proteasome pathways. J Mol Cell Cardiol 2010; 49:918-30. [PMID: 20863832 PMCID: PMC2975794 DOI: 10.1016/j.yjmcc.2010.09.004] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2010] [Revised: 09/01/2010] [Accepted: 09/01/2010] [Indexed: 11/12/2022]
Abstract
Disease-causing mutations of genes encoding small MW heat shock proteins (sHSPs) constitute a growing family of inherited myofibrillar disorders. In the present work, we found that three structurally-distinct CryAB mutants R120G, 450delA and 464delCT are mostly present in the detergent-insoluble fractions when overexpressed in H9c2 rat heart cells. We found that either over-expression or knockdown of HSPB1, a related sHSP, affects the solubility, stability, and degradation of aggregation-prone CryAB mutants. HSPB1 overexpression has negligible effects on the solubility and protein aggregates of either R120G and/or 450delA but increased the solubility and prevented formation of 464delCT aggregates. HSPB1 knockdown decreased solubility and increased protein aggregates of all CryAB mutants, indicating a key role for HSPB1 in clearance of CryAB mutants under basal conditions. We provide four lines of evidence that such selective clearance of R120G, 450delA and 464delCT mutants by HSPB1 is mediated by the ubiquitin-proteasome system (UPS). First, we found that treatment with the proteasome inhibitors increased the levels of all CryAB mutants. Second, R120G and 450delA overexpression corresponded to the accumulation of their specific ubiquitin conjugates in H9c2 cells. Third, HSPB1 knockdown directly increased the levels of all polyubiquitin conjugates. And fourth, the selective attenuation of 464delCT expression by HSPB1 over-expression was abrogated by the proteasome inhibition. We conclude that such selective interactions between CryAB mutants and HSPB1 overexpression might have important implications for the clinical manifestations and potential treatment.
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Affiliation(s)
- Huali Zhang
- Center for Cardiovascular Translational Biomedicine, Division of Cardiology, Department of Internal Medicine, University of Utah School of Medicine, Salt Lake City, UT 84132, USA
| | - Namakkal S. Rajasekaran
- Center for Cardiovascular Translational Biomedicine, Division of Cardiology, Department of Internal Medicine, University of Utah School of Medicine, Salt Lake City, UT 84132, USA
| | - Andras Orosz
- Center for Cardiovascular Translational Biomedicine, Division of Cardiology, Department of Internal Medicine, University of Utah School of Medicine, Salt Lake City, UT 84132, USA
| | - Xianzhong Xiao
- Department of Pathophysiology, Central South University, Changsha City, Hunan 41008, China
| | - Martin Rechsteiner
- Department of Biochemistry, University of Utah, School of Medicine, Salt Lake City, UT 84132, USA
| | - Ivor J. Benjamin
- Center for Cardiovascular Translational Biomedicine, Division of Cardiology, Department of Internal Medicine, University of Utah School of Medicine, Salt Lake City, UT 84132, USA
- Department of Biochemistry, University of Utah, School of Medicine, Salt Lake City, UT 84132, USA
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Howarth JL, Glover CPJ, Uney JB. HSP70 interacting protein prevents the accumulation of inclusions in polyglutamine disease1. J Neurochem 2010. [DOI: 10.1111/j.0022-3042.2008.05847.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Fedorova M, Kuleva N, Hoffmann R. Reversible and irreversible modifications of skeletal muscle proteins in a rat model of acute oxidative stress. Biochim Biophys Acta Mol Basis Dis 2009; 1792:1185-93. [PMID: 19786098 DOI: 10.1016/j.bbadis.2009.09.011] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2009] [Revised: 08/15/2009] [Accepted: 09/21/2009] [Indexed: 11/30/2022]
Abstract
Oxidative stress caused by an imbalance of the production of "reactive oxygen species" (ROS) and cellular scavenging systems is known to a play a key role in the development of various diseases and aging processes. Such elevated ROS levels can damage all components of cells, including proteins, lipids and DNA. Here, we study the influence of highly reactive ROS species on skeletal muscle proteins in a rat model of acute oxidative stress caused by X-ray irradiation at different time points. Protein preparations depleted for functional actin by polymerization were separated by gel electrophoresis in two dimensions by applying first non-reductive and then reductive conditions in SDS-PAGE. This diagonal redox SDS-PAGE revealed significant alterations to intra- and inter-molecular disulfide bridges for several proteins, but especially actin, creatine kinase and different isoforms of the myosin light chain. Though the levels of these reversible modifications were increased by oxidative stress, all proteins followed different kinetics. Moreover, a significant degree of protein was irreversibly oxidized (carbonylated), as revealed by western blot analyses performed at different time points.
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Affiliation(s)
- Maria Fedorova
- Institute of Bioanalytical Chemistry, Center for Biotechnology and Biomedicine, Faculty of Chemistry and Mineralogy, Leipzig University, Deutscher Platz 5, 04103 Leipzig, Germany
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Wang A, Liu X, Sheng S, Ye H, Peng T, Shi F, Crowe DL, Zhou X. Dysregulation of heat shock protein 27 expression in oral tongue squamous cell carcinoma. BMC Cancer 2009; 9:167. [PMID: 19497117 PMCID: PMC2696470 DOI: 10.1186/1471-2407-9-167] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2008] [Accepted: 06/04/2009] [Indexed: 12/04/2022] Open
Abstract
Background Recent proteomic studies identified Hsp27 as a highly over-expressed protein in oral squamous cell carcinoma (OSCC). Clinical studies that attempted to evaluate the prognostic values of Hsp27 yielded inconsistent results, which may be due to inclusion of OSCC cases from multiple anatomic sites. In this study, to determine the utility of Hsp27 for prognosis, we focused on oral tongue SCC (OTSCC), one of the most aggressive forms of OSCC. Methods Archival clinical samples of 15 normal oral tongue mucosa, 31 dysplastic lesions, 80 primary OTSCC, and 32 lymph node metastases were examined for Hsp27 expression by immunohistochemistry (IHC). Statistical analyses were carried out to assess the prognostic value of Hsp27 expression for patients with this disease. Results Dysregulation of Hsp27 expression was observed in dysplastic lesions, primary OTSCC, and lymph node metastases, and appears to be associated with disease progression. Statistical analysis revealed that the reduced Hsp27 expression in primary tumor tissue was associated with poor differentiation. Furthermore, the higher expression of Hsp27 was correlated with better overall survival. Conclusion Our study confirmed that the dysregulation of Hsp27 expression is a frequent event during the progression of OTSCC. The expression of Hsp27 appears to be an independent prognostic marker for patients with this disease.
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Affiliation(s)
- Anxun Wang
- Center for Molecular Biology of Oral Diseases, College of Dentistry, University of Illinois at Chicago, Chicago, USA.
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Howarth JL, Glover CPJ, Uney JB. HSP70 interacting protein prevents the accumulation of inclusions in polyglutamine disease. J Neurochem 2009; 108:945-951. [PMID: 19183265 PMCID: PMC2779461 DOI: 10.1111/j.1471-4159.2008.05847.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Heat shock proteins (HSPs) are associated with the proteinaceous inclusions that characterise many neurodegenerative diseases. This suggests they may be associated with disease aetiology and/or represents an attempt to remove abnormal protein aggregates. In this study the adenoviral mediated over-expression of HSP70 interacting protein (HIP) alone was shown to significantly reduce inclusion formation in both an in vitro model of Spinal Bulbar Muscular Atrophy and a primary neuronal model of polyglutamine disease. Experiments to determine the mechanism of action showed that: denatured luciferase activity (a measure of protein refolding) was not increased in the presence of HIP alone but was increased when HIP was co-expressed with HSP70 or Heat Shock cognate protein 70 (HSC70); the expression of polyglutamine inclusions in cortical neurons mediated an increase in the levels of HSC70 but not HSP70. Our data suggest that HIP may prevent inclusion formation by facilitating the constitutive HSC70 refolding cycle and possibly by preventing aggregation. HIP expression is not increased following stress and its over-expression may therefore reduce toxic polyglutamine aggregation events and contribute to an effective therapeutic strategy.
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Cavalli A, Bolognesi ML, Minarini A, Rosini M, Tumiatti V, Recanatini M, Melchiorre C. Multi-target-directed ligands to combat neurodegenerative diseases. J Med Chem 2008; 51:347-72. [PMID: 18181565 DOI: 10.1021/jm7009364] [Citation(s) in RCA: 833] [Impact Index Per Article: 52.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Andrea Cavalli
- Department of Pharmaceutical Sciences, Alma Mater Studiorum, University of Bologna, Bologna, Italy.
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Abstract
Most proteins in the cell adopt a compact, globular fold that determines their stability and function. Partial protein unfolding under conditions of cellular stress results in the exposure of hydrophobic regions normally buried in the interior of the native structure. Interactions involving the exposed hydrophobic surfaces of misfolded protein conformers lead to the formation of toxic aggregates, including oligomers, protofibrils and amyloid fibrils. A significant number of human disorders (e.g. Alzheimer disease, Parkinson disease, Huntington disease, amyotrophic lateral sclerosis and type II diabetes) are characterised by protein misfolding and aggregation. Over the past five years, outstanding progress has been made in the development of therapeutic strategies targeting these diseases. Three promising approaches include: (1) inhibiting protein aggregation with peptides or small molecules identified via structure-based drug design or high-throughput screening; (2) interfering with post-translational modifications that stimulate protein misfolding and aggregation; and (3) upregulating molecular chaperones or aggregate-clearance mechanisms. Ultimately, drug combinations that capitalise on more than one therapeutic strategy will constitute the most effective treatment for patients with these devastating illnesses.
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Affiliation(s)
- Jean-Christophe Rochet
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, 575 Stadium Mall Drive, RHPH 410A, West Lafayette, IN 47907, USA.
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Abstract
When properly controlled, Ca2+ fluxes across the plasma membrane and between intracellular compartments play critical roles in fundamental functions of neurons, including the regulation of neurite outgrowth and synaptogenesis, synaptic transmission and plasticity, and cell survival. During aging, and particularly in neurodegenerative disorders, cellular Ca2+-regulating systems are compromised resulting in synaptic dysfunction, impaired plasticity and neuronal degeneration. Oxidative stress, perturbed energy metabolism and aggregation of disease-related proteins (amyloid beta-peptide, alpha-synuclein, huntingtin, etc.) adversely affect Ca2+ homeostasis by mechanisms that have been elucidated recently. Alterations of Ca2+-regulating proteins in the plasma membrane (ligand- and voltage-gated Ca2+ channels, ion-motive ATPases, and glucose and glutamate transporters), endoplasmic reticulum (presenilin-1, Herp, and ryanodine and inositol triphosphate receptors), and mitochondria (electron transport chain proteins, Bcl-2 family members, and uncoupling proteins) are implicated in age-related neuronal dysfunction and disease. The adverse effects of aging on neuronal Ca2+ regulation are subject to modification by genetic (mutations in presenilins, alpha-synuclein, huntingtin, or Cu/Zn-superoxide dismutase; apolipoprotein E isotype, etc.) and environmental (dietary energy intake, exercise, exposure to toxins, etc.) factors that may cause or affect the risk of neurodegenerative disease. A better understanding of the cellular and molecular mechanisms that promote or prevent disturbances in cellular Ca2+ homeostasis during aging may lead to novel approaches for therapeutic intervention in neurological disorders such as Alzheimer's and Parkinson's diseases and stroke.
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Affiliation(s)
- Mark P Mattson
- Laboratory of Neurosciences, National Institute on Aging Intramural Research Program, Baltimore, MD, USA.
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Arrigo AP, Simon S, Gibert B, Kretz-Remy C, Nivon M, Czekalla A, Guillet D, Moulin M, Diaz-Latoud C, Vicart P. Hsp27 (HspB1) and alphaB-crystallin (HspB5) as therapeutic targets. FEBS Lett 2007; 581:3665-74. [PMID: 17467701 DOI: 10.1016/j.febslet.2007.04.033] [Citation(s) in RCA: 233] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2007] [Revised: 04/11/2007] [Accepted: 04/15/2007] [Indexed: 12/11/2022]
Abstract
Hsp27 and alphaB-crystallin are molecular chaperones that are constitutively expressed in several mammalian cells, particularly in pathological conditions. These proteins share functions as diverse as protection against toxicity mediated by aberrantly folded proteins or oxidative-inflammation conditions. In addition, these proteins share anti-apoptotic properties and are tumorigenic when expressed in cancer cells. This review summarizes the current knowledge about Hsp27 and alphaB-crystallin and the implications, either positive or deleterious, of these proteins in pathologies such as neurodegenerative diseases, myopathies, asthma, cataracts and cancers. Approaches towards therapeutic strategies aimed at modulating the expression and/or the activities of Hsp27 and alphaB-crystallin are presented.
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Affiliation(s)
- André-Patrick Arrigo
- Laboratoire Stress, Chaperons et Mort Cellulaire, CNRS, UMR5534, Centre de Génétique Moléculaire et Cellulaire, Université Lyon 1, Bat. Gregor Mendel, 16 Rue Dubois, F-69622, Villeurbanne Cedex, France.
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Firdaus WJJ, Wyttenbach A, Giuliano P, Kretz-Remy C, Currie RW, Arrigo AP. Huntingtin inclusion bodies are iron-dependent centers of oxidative events. FEBS J 2007; 273:5428-41. [PMID: 17116244 DOI: 10.1111/j.1742-4658.2006.05537.x] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Recently, we reported that the transient expression of huntingtin exon1 polypeptide containing polyglutamine tracts of various sizes (httEx1-polyQ) in cell models of Huntington disease generated an oxidative stress whose intensity was CAG repeat expansion-dependent. Here, we have analyzed the intracellular localization of the oxidative events generated by the httEx1-polyQ polypeptides. Analysis of live COS-7 cells as well as neuronal SK-N-SH and PC12 cells incubated with hydroethidine or dichlorofluorescein diacetate revealed oxidation of these probes at the level of the inclusion bodies formed by httEx1-polyQ polypeptides. The intensity and frequency of the oxidative events among the inclusions were CAG repeat expansion-dependent. Electron microscopic analysis of cell sections revealed the presence of oxidation-dependent morphologic alterations in the vicinity of httEx1-polyQ inclusion bodies. Moreover, a high level of oxidized proteins was recovered in partially purified inclusions. We also report that the iron chelator deferroxamine altered the structure, localization and oxidative potential of httEx1-polyQ inclusion bodies. Hence, despite the fact that the formation of inclusion bodies may represent a defense reaction of the cell to eliminate httEx1 mutant polypeptide, this phenomenon appears inherent to the generation of iron-dependent oxidative events that can be deleterious to the cell.
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Affiliation(s)
- Wance J J Firdaus
- Laboratoire Stress Oxydant, Chaperons et Apoptose, Université Claude Bernard Lyon-1, Villeurbanne, France
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