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Keillor JW, Johnson GVW. Transglutaminase 2 as a therapeutic target for neurological conditions. Expert Opin Ther Targets 2021; 25:721-731. [PMID: 34607527 DOI: 10.1080/14728222.2021.1989410] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Accepted: 10/01/2021] [Indexed: 12/14/2022]
Abstract
INTRODUCTION Transglutaminase 2 (TG2) has been implicated in numerous neurological conditions, including neurodegenerative diseases, multiple sclerosis, and CNS injury. Early studies on the role of TG2 in neurodegenerative conditions focused on its ability to 'crosslink' proteins into insoluble aggregates. However, more recent studies have suggested that this is unlikely to be the primary mechanism by which TG2 contributes to the pathogenic processes. Although the specific mechanisms by which TG2 is involved in neurological conditions have not been clearly defined, TG2 regulates numerous cellular processes through which it could contribute to a specific disease. Given the fact that TG2 is a stress-induced gene and elevated in disease or injury conditions, TG2 inhibitors may be useful neurotherapeutics. AREAS COVERED Overview of TG2 and different TG2 inhibitors. A brief review of TG2 in neurodegenerative diseases, multiple sclerosis and CNS injury and inhibitors that have been tested in different models. Database search: https://pubmed.ncbi.nlm.nih.gov prior to 1 July 2021. EXPERT OPINION Currently, it appears unlikely that inhibiting TG2 in the context of neurodegenerative diseases would be therapeutically advantageous. However, for multiple sclerosis and CNS injuries, TG2 inhibitors may have the potential to be therapeutically useful and thus there is rationale for their further development.
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Affiliation(s)
- Jeffrey W Keillor
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, ON, Canada
| | - Gail V W Johnson
- Department of Anesthesiology and Perioperative Medicine, University of Rochester, Rochester, NY, USA
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2
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Gaetano Gatta N, Romano R, Fioretti E, Gentile V. Transglutaminase inhibition: possible therapeutic mechanisms to protect cells from death in neurological disorders. AIMS MOLECULAR SCIENCE 2017. [DOI: 10.3934/molsci.2017.4.399] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Lai TS, Lin CJ, Greenberg CS. Role of tissue transglutaminase-2 (TG2)-mediated aminylation in biological processes. Amino Acids 2016; 49:501-515. [PMID: 27270573 DOI: 10.1007/s00726-016-2270-8] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Accepted: 05/31/2016] [Indexed: 01/08/2023]
Abstract
Post-translational modification (PTM) is an important mechanism in modulating a protein's structure and can lead to substantial diversity in biological function. Compared to other forms of PTMs such as phosphorylation, acetylation and glycosylation, the physiological significance of aminylation is limited. Aminylation refers to the covalent incorporation of biogenic/polyamines into target protein by calcium-dependent transglutaminases (TGs). The development of novel and more sensitive techniques has led to more proteins identified as tissue transglutaminase (TG2) substrates and potential targets for aminylation. Many of these substrate proteins play a role in cell signaling, cytoskeleton organization, muscle contraction, and inflammation. TG2 is well studied and widely expressed in a variety of tissues and will be the primary focus of this review on recent advance in transglutaminase-mediated aminylation.
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Affiliation(s)
- Thung-S Lai
- Graduate Institute of Biomedical Science, Mackay Medical College, No. 46, Sec. 3, Jhong-Jheng Rd., Sanzhi Dist, New Taipei City, 25200, Taiwan, ROC.
| | - Cheng-Jui Lin
- Nephrology/Department of Internal Medicine, Mackay Memorial Hospital, Taipei, Taiwan, ROC
- Nursing and Management, Mackay Junior College of Medicine, Taipei, Taiwan, ROC
| | - Charles S Greenberg
- Department of Medicine, Medical University of South Carolina, Charleston, SC, 29425, USA
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Gaetano Gatta N, Cammarota G, Gentile V. Possible roles of transglutaminases in molecular mechanisms responsible for human neurodegenerative diseases. AIMS BIOPHYSICS 2016. [DOI: 10.3934/biophy.2016.4.529] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Serretiello E, Iannaccone M, Titta F, G. Gatta N, Gentile V. Possible pathophysiological roles of transglutaminase-catalyzed reactions in the pathogenesis of human neurodegenerative diseases. AIMS BIOPHYSICS 2015. [DOI: 10.3934/biophy.2015.4.441] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Jeitner TM, Battaile K, Cooper AJL. γ-Glutamylamines and neurodegenerative diseases. Amino Acids 2012; 44:129-42. [PMID: 22407484 DOI: 10.1007/s00726-011-1209-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2011] [Accepted: 12/22/2011] [Indexed: 12/12/2022]
Abstract
Transglutaminases catalyze the formation of γ-glutamylamines utilizing glutamyl residues and amine-bearing compounds such as lysyl residues and polyamines. These γ-glutamylamines can be released from proteins by proteases in an intact form. The free γ-glutamylamines can be catabolized to 5-oxo-L-proline and the free amine by γ-glutamylamine cyclotransferase. Free γ-glutamylamines, however, accumulate in the CSF and affected areas of Huntington Disease brain. This observation suggests transglutaminase-derived γ-glutamylamines may play a more significant role in neurodegeneration than previously thought. The following monograph reviews the metabolism of γ-glutamylamines and examines the possibility that these species contribute to neurodegeneration.
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Affiliation(s)
- Thomas M Jeitner
- Neurosciences, Biomedical Research Core, Winthrop University Hospital, 222 Station Plaza North, Mineola, USA.
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Gentile V. Physiopathological roles of human transglutaminase 2. ADVANCES IN ENZYMOLOGY AND RELATED AREAS OF MOLECULAR BIOLOGY 2011; 78:47-95. [PMID: 22220472 DOI: 10.1002/9781118105771.ch2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Vittorio Gentile
- Department of Biochemistry and Biophysics, Medical School, Second University of Naples, Naples, Italy
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Beta-Actin is a Target for Transglutaminase Activity at Synaptic Endings in Chicken Telencephalic Cell Cultures. J Mol Neurosci 2011; 46:410-9. [DOI: 10.1007/s12031-011-9601-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2011] [Accepted: 07/13/2011] [Indexed: 10/18/2022]
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Ricotta M, Iannuzzi M, Vivo GD, Gentile V. Physio-pathological roles of transglutaminase-catalyzed reactions. World J Biol Chem 2010; 1:181-7. [PMID: 21541002 PMCID: PMC3083958 DOI: 10.4331/wjbc.v1.i5.181] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2010] [Revised: 05/04/2010] [Accepted: 05/14/2010] [Indexed: 02/05/2023] Open
Abstract
Transglutaminases (TGs) are a large family of related and ubiquitous enzymes that catalyze post-translational modifications of proteins. The main activity of these enzymes is the cross-linking of a glutaminyl residue of a protein/peptide substrate to a lysyl residue of a protein/peptide co-substrate. In addition to lysyl residues, other second nucleophilic co-substrates may include monoamines or polyamines (to form mono- or bi-substituted /crosslinked adducts) or -OH groups (to form ester linkages). In the absence of co-substrates, the nucleophile may be water, resulting in the net deamidation of the glutaminyl residue. The TG enzymes are also capable of catalyzing other reactions important for cell viability. The distribution and the physiological roles of TG enzymes have been widely studied in numerous cell types and tissues and their roles in several diseases have begun to be identified. “Tissue” TG (TG2), a member of the TG family of enzymes, has definitely been shown to be involved in the molecular mechanisms responsible for a very widespread human pathology: i.e. celiac disease (CD). TG activity has also been hypothesized to be directly involved in the pathogenetic mechanisms responsible for several other human diseases, including neurodegenerative diseases, which are often associated with CD. Neurodegenerative diseases, such as Alzheimer’s disease, Parkinson’s disease, supranuclear palsy, Huntington’s disease and other recently identified polyglutamine diseases, are characterized, in part, by aberrant cerebral TG activity and by increased cross-linked proteins in affected brains. In this review, we discuss the physio-pathological role of TG-catalyzed reactions, with particular interest in the molecular mechanisms that could involve these enzymes in the physio-pathological processes responsible for human neurodegenerative diseases.
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Affiliation(s)
- Mariangela Ricotta
- Mariangela Ricotta, Maura Iannuzzi, Giulia De Vivo, Vittorio Gentile, Department of Biochemistry and Biophysics, Medical School, Second University of Naples, via Costantinopoli 16, 80138 Napoli, Italy
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Jeitner TM, Muma NA, Battaile KP, Cooper AJ. Transglutaminase activation in neurodegenerative diseases. FUTURE NEUROLOGY 2009; 4:449-467. [PMID: 20161049 DOI: 10.2217/fnl.09.17] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The following review examines the role of calcium in promoting the in vitro and in vivo activation of transglutaminases in neurodegenerative disorders. Diseases such as Alzheimer's disease, Parkinson's disease and Huntington's disease exhibit increased transglutaminase activity and rises in intracellular calcium concentrations, which may be related. The aberrant activation of transglutaminase by calcium is thought to give rise to a variety of pathological moieties in these diseases, and the inhibition has been shown to have therapeutic benefit in animal and cellular models of neurodegeneration. Given the potential clinical relevance of transglutaminase inhibitors, we have also reviewed the recent development of such compounds.
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Affiliation(s)
- Thomas M Jeitner
- Applied Bench Core, Winthrop University Hospital, 222 Station Plaza North, Suite 502, Mineola, NY 11501, USA Tel.: +1 516 663 3455
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Wilhelmus MMM, Verhaar R, Bol JGJM, van Dam AM, Hoozemans JJM, Rozemuller AJM, Drukarch B. Novel role of transglutaminase 1 in corpora amylacea formation? Neurobiol Aging 2009; 32:845-56. [PMID: 19464759 DOI: 10.1016/j.neurobiolaging.2009.04.019] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2008] [Revised: 04/06/2009] [Accepted: 04/21/2009] [Indexed: 10/20/2022]
Abstract
Corpora amylacea (CA) are both age and neurodegeneration-related spherical bodies, consisting of polymerized proteins, often thought to be involved in sequestration of hazardous products of cellular metabolism in brain. Although CA formation is associated with cellular stress, the process underlying their formation remains obscure. Transglutaminases (TGs) are stress associated enzymes that induce molecular cross-links, leading to polymerization of substrate proteins. TG expression and activity are elevated in Alzheimer's disease (AD) and Parkinson's disease (PD), and TG-catalyzed cross-links are present in their lesions. Considering the nature of CA, the aim of this study was to investigate the presence of TGs and TG cross-links in CA of healthy aging brain, AD and PD brain, using immunohistochemistry. We observed TG1 and TG cross-links in CA, together with typical cytoskeletal proteins. Furthermore, the presence of proteins associated with AD or PD pathogenesis was not altered in CA of disease brain compared to controls. We propose that TG1-catalyzed cross-linking and consequent polymerization of cytoskeletal and cytoskeleton-associated proteins may underlie CA formation.
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Affiliation(s)
- Micha M M Wilhelmus
- Department of Anatomy and Neurosciences, VU University Medical Center, Neuroscience Campus Amsterdam, The Netherlands.
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Jeitner TM, Pinto JT, Krasnikov BF, Horswill M, Cooper AJL. Transglutaminases and neurodegeneration. J Neurochem 2009; 109 Suppl 1:160-6. [PMID: 19393023 DOI: 10.1111/j.1471-4159.2009.05843.x] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Transglutaminases (TGs) are Ca2+-dependent enzymes that catalyze a variety of modifications of glutaminyl (Q) residues. In the brain, these modifications include the covalent attachment of a number of amine-bearing compounds, including lysyl (K) residues and polyamines, which serve to either regulate enzyme activity or attach the TG substrates to biological matrices. Aberrant TG activity is thought to contribute to Alzheimer disease, Parkinson disease, Huntington disease, and supranuclear palsy. Strategies designed to interfere with TG activity have some benefit in animal models of Huntington and Parkinson diseases. The following review summarizes the involvement of TGs in neurodegenerative diseases and discusses the possible use of selective inhibitors as therapeutic agents in these diseases.
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Segers-Nolten IMJ, Wilhelmus MMM, Veldhuis G, van Rooijen BD, Drukarch B, Subramaniam V. Tissue transglutaminase modulates alpha-synuclein oligomerization. Protein Sci 2008; 17:1395-402. [PMID: 18505736 DOI: 10.1110/ps.036103.108] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
We have studied the interaction of the enzyme tissue transglutaminase (tTG), catalyzing cross-link formation between protein-bound glutamine residues and primary amines, with Parkinson's disease-associated alpha-synuclein protein variants at physiologically relevant concentrations. We have, for the first time, determined binding affinities of tTG for wild-type and mutant alpha-synucleins using surface plasmon resonance approaches, revealing high-affinity nanomolar equilibrium dissociation constants. Nanomolar tTG concentrations were sufficient for complete inhibition of fibrillization by effective alpha-synuclein cross-linking, resulting predominantly in intramolecularly cross-linked monomers accompanied by an oligomeric fraction. Since oligomeric species have a pathophysiological relevance we further investigated the properties of the tTG/alpha-synuclein oligomers. Atomic force microscopy revealed morphologically similar structures for oligomers from all alpha-synuclein variants; the extent of oligomer formation was found to correlate with tTG concentration. Unlike normal alpha-synuclein oligomers the resultant structures were extremely stable and resistant to GdnHCl and SDS. In contrast to normal beta-sheet-containing oligomers, the tTG/alpha-synuclein oligomers appear to be unstructured and are unable to disrupt phospholipid vesicles. These data suggest that tTG binds equally effective to wild-type and disease mutant alpha-synuclein variants. We propose that tTG cross-linking imposes structural constraints on alpha-synuclein, preventing the assembly of structured oligomers required for disruption of membranes and for progression into fibrils. In general, cross-linking of amyloid forming proteins by tTG may prevent the progression into pathogenic species.
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Affiliation(s)
- Ine M J Segers-Nolten
- Biophysical Engineering Group, MESA+ Institute for Nanotechnology and Institute for Biomedical Technology, University of Twente, 7500 AE Enschede, The Netherlands
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Hartley DM, Zhao C, Speier AC, Woodard GA, Li S, Li Z, Walz T. Transglutaminase induces protofibril-like amyloid beta-protein assemblies that are protease-resistant and inhibit long-term potentiation. J Biol Chem 2008; 283:16790-800. [PMID: 18397883 DOI: 10.1074/jbc.m802215200] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
An increasing body of evidence suggests that soluble assemblies of amyloid beta-protein (Abeta) play an important role in the initiation of Alzheimer disease (AD). In vitro studies have found that synthetic Abeta can form soluble aggregates through self-assembly, but this process requires Abeta concentrations 100- to 1000-fold greater than physiological levels. Tissue transglutaminase (TGase) has been implicated in neurodegeneration and can cross-link Abeta. Here we show that TGase induces rapid aggregation of Abeta within 0.5-30 min, which was not observed with chemical cross-linkers. Both Abeta40 and Abeta42 are good substrates for TGase but show different aggregation patterns. Guinea pig and human TGase induced similar Abeta aggregation patterns, and oligomerization was observed with Abeta40 concentrations as low as 50 nm. The formed Abeta40 species range from 5 to 6 nm spheres to curvilinear structures of the same width, but up to 100 nm in length, that resemble the previously described self-assembled Abeta protofibrils. TGase-induced Abeta40 assemblies are resistant to a 1-h incubation with either neprilysin or insulin degrading enzyme, whereas the monomer is rapidly degraded by both proteases. In support of these species being pathological, TGase-induced Abeta40 assemblies (100 nm) inhibited long term potentiation recorded in the CA1 region of mouse hippocampus slices. Our data suggest that TGase can contribute to AD by initiating Abeta oligomerization and aggregation at physiological levels, by reducing the clearance of Abeta due to the generation of protease-resistant Abeta species, and by forming Abeta assemblies that inhibit processes involved in memory and learning. Our data suggest that TGase might constitute a specific therapeutic target for slowing or blocking the progression of AD.
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Affiliation(s)
- Dean M Hartley
- Department of Neurological Sciences, Rush University Medical Center, Chicago, Illinois 60612, USA.
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von Horsten HH, Johnson SS, SanFrancisco SK, Hastert MC, Whelly SM, Cornwall GA. Oligomerization and transglutaminase cross-linking of the cystatin CRES in the mouse epididymal lumen: potential mechanism of extracellular quality control. J Biol Chem 2007; 282:32912-23. [PMID: 17855342 DOI: 10.1074/jbc.m703956200] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
CRES (cystatin-related epididymal spermatogenic), a member of the cystatin superfamily of cysteine protease inhibitors, is expressed in the epididymis and spermatozoa, suggesting specialized roles in reproduction. Several cystatin family members oligomerize, including cystatin C that forms amyloid deposits associated with cerebral amyloid angiopathy. Our studies demonstrate that CRES also forms oligomers. Size exclusion chromatography revealed the presence of multiple forms of CRES in the epididymal luminal fluid, including SDS-sensitive and SDS-resistant high molecular mass complexes. In vitro experiments demonstrated that CRES is a substrate for transglutaminase and that an endogenous transglutaminase activity in the epididymal lumen catalyzed the formation of SDS-resistant CRES complexes. The use of a conformation-dependent antibody that recognizes only the oligomeric precursors to amyloid, negative stain electron microscopy, and Congo Red staining showed that CRES adopted similar oligomeric and fibrillar structures during its aggregation as other amyloidogenic proteins, suggesting that CRES has the potential to form amyloid in the epididymal lumen. The addition of transglutaminase, however, prevented the formation of CRES oligomers recognized by the conformation antibody by cross-linking CRES into an amorphous structure. We propose that transglutaminase activity in the epididymal lumen may function as a mechanism of extracellular quality control by diverting proteins such as CRES from the amyloidogenic pathway.
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Affiliation(s)
- Hans H von Horsten
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, 3601 4th Street, Lubbock, TX 79430, USA
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Cornwall GA, von Horsten HH, Swartz D, Johnson S, Chau K, Whelly S. Extracellular quality control in the epididymis. Asian J Androl 2007; 9:500-7. [PMID: 17589787 DOI: 10.1111/j.1745-7262.2007.00309.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
The epididymal lumen represents a unique extracellular environment because of the active sperm maturation process that takes place within its confines. Although much focus has been placed on the interaction of epididymal secretory proteins with spermatozoa in the lumen, very little is known regarding how the complex epididymal milieu as a whole is maintained, including mechanisms to prevent or control proteins that may not stay in their native folded state following secretion. Because some misfolded proteins can form cytotoxic aggregate structures known as amyloid, it is likely that control/surveillance mechanisms exist within the epididymis to protect against this process and allow sperm maturation to occur. To study protein aggregation and to identify extracellular quality control mechanisms in the epididymis, we used the cystatin family of cysteine protease inhibitors, including cystatin-related epididymal spermatogenic and cystatin C as molecular models because both proteins have inherent properties to aggregate and form amyloid. In this chapter, we present a brief summary of protein aggregation by the amyloid pathway based on what is known from other organ systems and describe quality control mechanisms that exist intracellularly to control protein misfolding and aggregation. We then present a summary of our studies of cystatin-related epididymal spermatogenic (CRES) oligomerization within the epididymal lumen, including studies suggesting that transglutaminase cross-linking may be one mechanism of extracellular quality control within the epididymis.
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Affiliation(s)
- Gail A Cornwall
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, 3601 4th Street, Lubbock, TX 79430, USA.
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Van Raamsdonk JM, Pearson J, Bailey CDC, Rogers DA, Johnson GVW, Hayden MR, Leavitt BR. Cystamine treatment is neuroprotective in the YAC128 mouse model of Huntington disease. J Neurochem 2005; 95:210-20. [PMID: 16181425 DOI: 10.1111/j.1471-4159.2005.03357.x] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Huntington disease (HD) is an adult onset neurodegenerative disorder characterized by selective atrophy and cell loss within the striatum. There is currently no treatment that can prevent the striatal neuropathology. Transglutaminase (TG) activity is increased in HD patients, is associated with cell death, and has been suggested to contribute to striatal neuronal loss in HD. This work assesses the therapeutic potential of cystamine, an inhibitor of TG activity with additional potentially beneficial effects. Specifically, we examine the effect of cystamine on striatal neuronal loss in the YAC128 mouse model of HD. We demonstrate here for the first time that YAC128 mice show a forebrain-specific increase in TG activity compared with wild-type (WT) littermates which is decreased by oral delivery of cystamine. Treatment of symptomatic YAC128 mice with cystamine starting at 7 months prevented striatal neuronal loss. Cystamine treatment also ameliorated the striatal volume loss and striatal neuronal atrophy observed in these animals, but was unable to prevent motor dysfunction or the down-regulation of dopamine and cyclic adenosine monophsophate-regulated phosphoprotein (DARPP-32) expression in the striatum. While the exact mechanism responsible for the beneficial effects of cystamine in YAC128 mice is uncertain, our findings suggest that cystamine is neuroprotective and may be beneficial in the treatment of HD.
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Affiliation(s)
- Jeremy M Van Raamsdonk
- Centre for Molecular Medicine and Therapeutics, Department of Medical Genetics and British Columbia Research Institute for Women and Children's Health, University of British Columbia, Vancouver, British Columbia, Canada
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