1
|
Tsai CY, Chen PH, Chen AL, Wang TSA. Spatiotemporal Investigation of Intercellular Heterogeneity via Multiple Photocaged Probes. Chemistry 2023; 29:e202301067. [PMID: 37382047 DOI: 10.1002/chem.202301067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 06/14/2023] [Accepted: 06/28/2023] [Indexed: 06/30/2023]
Abstract
Intercellular heterogeneity occurs widely under both normal physiological environments and abnormal disease-causing conditions. Several attempts to couple spatiotemporal information to cell states in a microenvironment were performed to decipher the cause and effect of heterogeneity. Furthermore, spatiotemporal manipulation can be achieved with the use of photocaged/photoactivatable molecules. Here, we provide a platform to spatiotemporally analyze differential protein expression in neighboring cells by multiple photocaged probes coupled with homemade photomasks. We successfully established intercellular heterogeneity (photoactivable ROS trigger) and mapped the targets (directly ROS-affected cells) and bystanders (surrounding cells), which were further characterized by total proteomic and cysteinomic analysis. Different protein profiles were shown between bystanders and target cells in both total proteome and cysteinome. Our strategy should expand the toolkit of spatiotemporal mapping for elucidating intercellular heterogeneity.
Collapse
Affiliation(s)
- Chun-Yi Tsai
- Department of Chemistry, National Taiwan University and Center for, Emerging Material and Advanced Devices, National Taiwan University, Taipei, 10617, Taiwan (R.O.C
| | - Po-Hsun Chen
- Department of Chemistry, National Taiwan University and Center for, Emerging Material and Advanced Devices, National Taiwan University, Taipei, 10617, Taiwan (R.O.C
| | - Ai-Lin Chen
- Department of Chemistry, National Taiwan University and Center for, Emerging Material and Advanced Devices, National Taiwan University, Taipei, 10617, Taiwan (R.O.C
| | - Tsung-Shing Andrew Wang
- Department of Chemistry, National Taiwan University and Center for, Emerging Material and Advanced Devices, National Taiwan University, Taipei, 10617, Taiwan (R.O.C
| |
Collapse
|
2
|
Kowluru A, Gleason NF. Underappreciated roles for Rho GDP dissociation inhibitors (RhoGDIs) in cell function: Lessons learned from the pancreatic islet β-cell. Biochem Pharmacol 2022; 197:114886. [PMID: 34968495 PMCID: PMC8858860 DOI: 10.1016/j.bcp.2021.114886] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 12/10/2021] [Accepted: 12/13/2021] [Indexed: 11/02/2022]
Abstract
Rho subfamily of G proteins (e.g., Rac1) have been implicated in glucose-stimulated insulin secretion from the pancreatic β-cell. Interestingly, metabolic stress (e.g., chronic exposure to high glucose) results in sustained activation of Rac1 leading to increased oxidative stress, impaired insulin secretion and β-cell dysfunction. Activation-deactivation of Rho G proteins is mediated by three classes of regulatory proteins, namely the guanine nucleotide exchange factors (GEFs), which facilitate the conversion of inactive G proteins to their active conformations; the GTPase-activating proteins (GAPs), which convert the active G proteins to their inactive forms); and the GDP-dissociation inhibitors (GDIs), which prevent the dissociation of GDP from G proteins. Contrary to a large number of GEFs (82 members) and GAPs (69 members), only three members of RhoGDIs (RhoGDIα, RhoGDIβ and RhoGDIγ) are expressed in mammalian cells.Even though relatively smaller in number, the GDIs appear to play essential roles in G protein function (e.g., subcellular targeting) for effector activation and cell regulation. Emerging evidence also suggests that the GDIs are functionally regulated via post-translational modification (e.g., phosphorylation) and by lipid second messengers, lipid kinases and lipid phosphatases. We highlight the underappreciated regulatory roles of RhoGDI-Rho G protein signalome in islet β-cell function in health and metabolic stress. Potential knowledge gaps in the field, and directions for future research for the identification of novel therapeutic targets to loss of functional β-cell mass under the duress of metabolic stress are highlighted.
Collapse
Affiliation(s)
- Anjaneyulu Kowluru
- Biomedical Research Service, John D. Dingell VA Medical Center and Department of Pharmaceutical Sciences, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University, Detroit, MI 48201, USA.
| | | |
Collapse
|
3
|
Burcham PC. Carbonyl scavengers as pharmacotherapies in degenerative disease: Hydralazine repurposing and challenges in clinical translation. Biochem Pharmacol 2018; 154:397-406. [PMID: 29883705 DOI: 10.1016/j.bcp.2018.06.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Accepted: 06/04/2018] [Indexed: 12/26/2022]
Abstract
During cellular metabolism, spontaneous oxidative damage to unsaturated lipids generates many electrophilic carbonyl compounds that readily attack cell macromolecules, forming adducts that are potential drivers of tissue dysfunction. Since such damage is heightened in many degenerative conditions, researchers have assessed the efficacy of nucleophilic carbonyl-trapping drugs in animal models of such disorders, anticipating that they will protect tissues by intercepting toxic lipid-derived electrophiles (LDEs) within cells. This Commentary explores recent animal evidence for carbonyl scavenger efficacy in two disparate yet significant conditions known to involve LDE production, namely spinal cord injury (SCI) and alcoholic liver disease (ALD). Primary emphasis is placed on studies that utilised hydralazine, a clinically-approved "broad-spectrum" scavenger known to trap multiple LDEs. In addition to reviewing recent studies of hydralazine efficacy in animal SCI and ALD models, the Commentary reviews new insights concerning novel lifespan- and healthspan-extending properties of hydralazine obtained during studies in model invertebrate organisms, since the mechanisms involved seem of likely benefit during the treatment of degenerative disease. Finally, noting that human translation of the histoprotective properties of hydralazine have been limited, the final section of the Commentary will address two obstacles that hamper clinical translation of LDE-trapping therapies while also suggesting potential strategies for overcoming these problems.
Collapse
Affiliation(s)
- Philip C Burcham
- Discipline of Pharmacology, School of Biomedical Science, The University of Western Australia, Crawley, WA 6007, Australia.
| |
Collapse
|
4
|
González-Forero D, Moreno-López B. Retrograde response in axotomized motoneurons: nitric oxide as a key player in triggering reversion toward a dedifferentiated phenotype. Neuroscience 2014; 283:138-65. [PMID: 25168733 DOI: 10.1016/j.neuroscience.2014.08.021] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2014] [Revised: 08/03/2014] [Accepted: 08/14/2014] [Indexed: 12/11/2022]
Abstract
The adult brain retains a considerable capacity to functionally reorganize its circuits, which mainly relies on the prevalence of three basic processes that confer plastic potential: synaptic plasticity, plastic changes in intrinsic excitability and, in certain central nervous system (CNS) regions, also neurogenesis. Experimental models of peripheral nerve injury have provided a useful paradigm for studying injury-induced mechanisms of central plasticity. In particular, axotomy of somatic motoneurons triggers a robust retrograde reaction in the CNS, characterized by the expression of plastic changes affecting motoneurons, their synaptic inputs and surrounding glia. Axotomized motoneurons undergo a reprograming of their gene expression and biosynthetic machineries which produce cell components required for axonal regrowth and lead them to resume a functionally dedifferentiated phenotype characterized by the removal of afferent synaptic contacts, atrophy of dendritic arbors and an enhanced somato-dendritic excitability. Although experimental research has provided valuable clues to unravel many basic aspects of this central response, we are still lacking detailed information on the cellular/molecular mechanisms underlying its expression. It becomes clear, however, that the state-switch must be orchestrated by motoneuron-derived signals produced under the direction of the re-activated growth program. Our group has identified the highly reactive gas nitric oxide (NO) as one of these signals, by providing robust evidence for its key role to induce synapse elimination and increases in intrinsic excitability following motor axon damage. We have elucidated operational principles of the NO-triggered downstream transduction pathways mediating each of these changes. Our findings further demonstrate that de novo NO synthesis is not only "necessary" but also "sufficient" to promote the expression of at least some of the features that reflect reversion toward a dedifferentiated state in axotomized adult motoneurons.
Collapse
Affiliation(s)
- D González-Forero
- Grupo de Neurodegeneración y Neuroreparación (GRUNEDERE), Área de Fisiología, Instituto de Biomoléculas (INBIO), Facultad de Medicina, Universidad de Cádiz, Cádiz, Spain.
| | - B Moreno-López
- Grupo de Neurodegeneración y Neuroreparación (GRUNEDERE), Área de Fisiología, Instituto de Biomoléculas (INBIO), Facultad de Medicina, Universidad de Cádiz, Cádiz, Spain.
| |
Collapse
|
5
|
Bachi A, Dalle-Donne I, Scaloni A. Redox Proteomics: Chemical Principles, Methodological Approaches and Biological/Biomedical Promises. Chem Rev 2012. [DOI: 10.1021/cr300073p] [Citation(s) in RCA: 189] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Angela Bachi
- Biological Mass Spectrometry Unit, San Raffaele Scientific Institute, 20132 Milan, Italy
| | | | - Andrea Scaloni
- Proteomics & Mass Spectrometry Laboratory, ISPAAM, National Research Council, 80147 Naples, Italy
| |
Collapse
|
6
|
Bae N, Lödl M, Pollak A, Lubec G. Mass spectrometrical analysis of bilin-binding protein from the wing of Hebomoia glaucippe (Linnaeus, 1758) (Lepidoptera: Pieridae). Electrophoresis 2012; 33:1787-94. [DOI: 10.1002/elps.201100569] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Narkhyun Bae
- Department of Pediatrics; Medical University of Vienna; Vienna; Austria
| | - Martin Lödl
- Naturhistorisches Museum Wien; Vienna; Austria
| | - Arnold Pollak
- Department of Pediatrics; Medical University of Vienna; Vienna; Austria
| | - Gert Lubec
- Department of Pediatrics; Medical University of Vienna; Vienna; Austria
| |
Collapse
|
7
|
Moreno-López B, Sunico CR, González-Forero D. NO orchestrates the loss of synaptic boutons from adult "sick" motoneurons: modeling a molecular mechanism. Mol Neurobiol 2010; 43:41-66. [PMID: 21190141 DOI: 10.1007/s12035-010-8159-8] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2010] [Accepted: 12/02/2010] [Indexed: 12/14/2022]
Abstract
Synapse elimination is the main factor responsible for the cognitive decline accompanying many of the neuropathological conditions affecting humans. Synaptic stripping of motoneurons is also a common hallmark of several motor pathologies. Therefore, knowledge of the molecular basis underlying this plastic process is of central interest for the development of new therapeutic tools. Recent advances from our group highlight the role of nitric oxide (NO) as a key molecule triggering synapse loss in two models of motor pathologies. De novo expression of the neuronal isoform of NO synthase (nNOS) in motoneurons commonly occurs in response to the physical injury of a motor nerve and in the course of amyotrophic lateral sclerosis. In both conditions, this event precedes synaptic withdrawal from motoneurons. Strikingly, nNOS-synthesized NO is "necessary" and "sufficient" to induce synaptic detachment from motoneurons. The mechanism involves a paracrine/retrograde action of NO on pre-synaptic structures, initiating a downstream signaling cascade that includes sequential activation of (1) soluble guanylyl cyclase, (2) cyclic guanosine monophosphate-dependent protein kinase, and (3) RhoA/Rho kinase (ROCK) signaling. Finally, ROCK activation promotes phosphorylation of regulatory myosin light chain, which leads to myosin activation and actomyosin contraction. This latter event presumably contributes to the contractile force to produce ending axon retraction. Several findings support that this mechanism may operate in the most prevalent neurodegenerative diseases.
Collapse
Affiliation(s)
- Bernardo Moreno-López
- Grupo de NeuroDegeneración y NeuroReparación (GRUNEDERE), Área de Fisiología, Facultad de Medicina, Universidad de Cádiz, Plaza Falla, 9, 11003 Cádiz, Spain.
| | | | | |
Collapse
|
8
|
Lü HZ, Wang YX, Zhou JS, Wang FC, Hu JG. Cyclosporin A increases recovery after spinal cord injury but does not improve myelination by oligodendrocyte progenitor cell transplantation. BMC Neurosci 2010; 11:127. [PMID: 20937147 PMCID: PMC2959094 DOI: 10.1186/1471-2202-11-127] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2009] [Accepted: 10/12/2010] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Transplantation of oligodendrocyte precursor cells (OPCs) is an attractive therapy for demyelinating diseases. Cyclosporin A (CsA) is one of the foremost immunosuppressive agents and has widespread use in tissue and cell transplantation. However, whether CsA affects survival and differentiation of engrafted OPCs in vivo is unknown. In this study, the effect of CsA on morphological, functional and immunological aspects, as well as survival and differentiation of engrafted OPCs in injured spinal cord was explored. RESULTS We transplanted green fluorescent protein (GFP) expressed OPCs (GFP-OPCs) into injured spinal cords of rats treated with or without CsA (10 mg/kg). Two weeks after cell transplantation, more GFP-positive cells were found in CsA-treated rats than that in vehicle-treated ones. However, the engrafted cells mostly differentiated into astrocytes, but not oligodendrocytes in both groups. In the CsA-treated group, a significant decrease in spinal cord lesion volume along with increase in spared myelin and neurons were found compared to the control group. Such histological improvement correlated well with an increase in behavioral recovery. Further study suggested that CsA treatment could inhibit infiltration of T cells and activation of resident microglia and/or macrophages derived from infiltrating monocytes in injured spinal cords, which contributes to the survival of engrafted OPCs and repair of spinal cord injury (SCI). CONCLUSIONS These results collectively indicate that CsA can promote the survival of engrafted OPCs in injured spinal cords, but has no effect on their differentiation. The engrafted cells mostly differentiated into astrocytes, but not oligodendrocytes. The beneficial effect of CsA on SCI and the survival of engrafted cells may be attributed to its neuroprotective effect.
Collapse
Affiliation(s)
- He-Zuo Lü
- Central Laboratory, First Affiliated Hospital of Bengbu Medical College, Anhui 233004, China
| | | | | | | | | |
Collapse
|
9
|
Afjehi-Sadat L, Brejnikow M, Kang SU, Vishwanath V, Walder N, Herkner K, Redl H, Lubec G. Differential protein levels and post-translational modifications in spinal cord injury of the rat. J Proteome Res 2010; 9:1591-7. [PMID: 20141154 DOI: 10.1021/pr901049a] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Although changes in protein expression in spinal cord injury (SCI) would be of pivotal interest, information so far is limited. It was therefore the aim of the study to determine protein levels and post-translational modifications in the early phase following SCI in the rat. SCI was induced in Sprague-Dawley rats and sham operated rats served as controls. A gel-based proteomic approach using two-dimensional gel electrophoresis followed by quantification with specific software and subsequent identification of differentially expressed proteins by nano-ESI-LC-MS/MS was applied. Proteins of several pathways and cascades were dysregulated in SCI: 14-3-3 epsilon protein, dynein light chain 1, and tubulin beta-5 chain showed higher levels in SCI, whereas adenylyl cyclase associated protein 1, dihydropyrimidinase-related protein 2, F-actin capping protein subunit beta, glyceraldehyde-3-phosphate dehydrogenase, stress-induced phosphoprotein 1 and transthyretin showed lower levels in the injured tissue. Post-translational modifications indicated free oxygen radical attack on proteins in SCI. The occurrence of stress is indicated by deranged stress-induced phosphoprotein 1 and signaling abnormalities are reflected by adenylyl cyclase-associated protein 1 and 14-3-3 epsilon protein. The findings propose the involvement of the corresponding cascades and challenge further work into aberrant signaling and oxidative stress in SCI, which may form the basis for experimental intervention for spinal cord trauma.
Collapse
|
10
|
Li L, Whittle N, Klug S, Chen WQ, Singewald N, Toth M, Lubec G. Serotonin(1A)-receptor-dependent signaling proteins in mouse hippocampus. Neuropharmacology 2009; 57:556-66. [PMID: 19607848 DOI: 10.1016/j.neuropharm.2009.07.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2008] [Revised: 06/30/2009] [Accepted: 07/07/2009] [Indexed: 11/18/2022]
Abstract
The serotonin(1A) receptor (5-HT(1A) R) knock-out mouse (KO) is a widely used animal model for anxiety and cognitive function and regulation of signaling cascades by this receptor has been reported. We aimed to determine individual representatives of signaling cascades in order to screen 5-HT(1A) R-dependent signaling proteins (SPs). Hippocampal proteins from wild type and 5-HT(1A) R KO mice were extracted, run on two-dimensional gel electrophoresis, proteins were identified by MALDI and nano-ESI-LC-MS/MS and SPs were quantified by specific software. Nucleoside diphosphate kinase A (NDK A, synonym: nm23), Dual specificity mitogen-activated protein kinase kinase 1 (MAPKK1, synonym: MEK), Serine/threonine-protein phosphatase PP1-gamma catalytic subunit (PP-1G), Septin-5, were reduced in the KO mice. Novel phosphorylation sites at T386 on MAPKK1 and at S225 and Y265 on Septin-5 were observed. MAPKK1 and PP-1G are known 5-HT(1A) R-dependent signaling compounds and are in agreement with receptor knock-out and septin-5 is involved in serotonin transport, although regulation by 5-HT(1A) R has not been reported. 5-HT(1A) R - dependent levels for NDK A have not been demonstrated so far and we herewith propose a role for NDK A in 5-HT(1A) R signaling. Reduced SP levels along with findings of two novel phosphorylation sites may be relevant for interpretation of previous and the design of future studies on this receptor system.
Collapse
MESH Headings
- Amino Acid Sequence
- Analysis of Variance
- Animals
- Blotting, Western
- Cytoskeletal Proteins/genetics
- Cytoskeletal Proteins/metabolism
- Databases, Genetic
- Electrophoresis, Gel, Two-Dimensional
- GTP-Binding Proteins/genetics
- GTP-Binding Proteins/metabolism
- Hippocampus/metabolism
- MAP Kinase Kinase 1/genetics
- MAP Kinase Kinase 1/metabolism
- Mice
- Mice, Knockout
- NM23 Nucleoside Diphosphate Kinases/metabolism
- Phosphorylation
- Protein Phosphatase 1/metabolism
- Receptor, Serotonin, 5-HT1A/genetics
- Receptor, Serotonin, 5-HT1A/metabolism
- Septins
- Signal Transduction
- Software
- Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
Collapse
Affiliation(s)
- Lin Li
- Department of Pediatrics, Medical University of Vienna, Währinger Gürtel 18-20, A-1090 Vienna, Austria
| | | | | | | | | | | | | |
Collapse
|
11
|
Manganese Enhanced Magnetic Resonance Imaging in a Contusion Model of Spinal Cord Injury in Rats: Correlation With Motor Function. Invest Radiol 2008; 43:277-83. [DOI: 10.1097/rli.0b013e318162f1bd] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
12
|
Weitzdörfer R, Höger H, Burda G, Pollak A, Lubec G. Differences in Hippocampal Protein Expression at 3 Days, 3 Weeks, and 3 Months Following Induction of Perinatal Asphyxia in the Rat. J Proteome Res 2008; 7:1945-52. [DOI: 10.1021/pr700835y] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Rachel Weitzdörfer
- Department of Pediatrics, Medical University of Vienna, Waehringer Guertel 18, 1090 Vienna, Austria, and Division for Laboratory Animal Science and Genetics, Medical University of Vienna, Brauhausgasse 34, 2325 Himberg, Austria
| | - Harald Höger
- Department of Pediatrics, Medical University of Vienna, Waehringer Guertel 18, 1090 Vienna, Austria, and Division for Laboratory Animal Science and Genetics, Medical University of Vienna, Brauhausgasse 34, 2325 Himberg, Austria
| | - Gudrun Burda
- Department of Pediatrics, Medical University of Vienna, Waehringer Guertel 18, 1090 Vienna, Austria, and Division for Laboratory Animal Science and Genetics, Medical University of Vienna, Brauhausgasse 34, 2325 Himberg, Austria
| | - Arnold Pollak
- Department of Pediatrics, Medical University of Vienna, Waehringer Guertel 18, 1090 Vienna, Austria, and Division for Laboratory Animal Science and Genetics, Medical University of Vienna, Brauhausgasse 34, 2325 Himberg, Austria
| | - Gert Lubec
- Department of Pediatrics, Medical University of Vienna, Waehringer Guertel 18, 1090 Vienna, Austria, and Division for Laboratory Animal Science and Genetics, Medical University of Vienna, Brauhausgasse 34, 2325 Himberg, Austria
| |
Collapse
|
13
|
Burcham PC. Potentialities and pitfalls accompanying chemico-pharmacological strategies against endogenous electrophiles and carbonyl stress. Chem Res Toxicol 2008; 21:779-86. [PMID: 18275160 DOI: 10.1021/tx700399q] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The use of powerful analytical technologies to detect endogenous carbonyls formed as byproducts of oxidative cell injury has revealed that these species contribute to many human diseases. As electrophiles, they are attacked by reactive centers in cell macromolecules to form adducts, the levels of which serve as useful biomarkers of oxidative cell injury. Because the pathobiological significance of such damage is often unclear, the possibility of using low molecular weight drugs as exploratory sacrificial nucleophiles to intercept reactive carbonyls within cells and tissues is appealing. This perspective highlights the potential benefits of using carbonyl scavengers to evaluate the significance of endogenous carbonyls in particular diseases but also canvasses a number of challenges confronting this therapeutic strategy. Chief among the latter is the task of confirming that carbonyl sequestration underlies any suppression of disease symptoms elicited by these multipotent reagents, an issue needing clarification if these compounds are to command consideration as drug interventions in humans. Other problems include adverse consequences of reactions between carbonyl scavengers and important endogenous carbonyls (e.g., neurotoxicity due to pyridoxal depletion), as well as the potential for drugs to form ternary complexes with carbonylated cell proteins, raising the prospect of immunotoxicological outcomes. Strategies for moving carbonyl sequestering reagents from the laboratory bench to a clinical testing environment are discussed within the context of the search for new treatments for spinal cord injury, one of the most debilitating medical conditions sustainable by humans. This condition seems an appropriate test case for assessing carbonyl sequestering drugs given growing evidence for noxious carbonyls in the wave of neuronal cell death that follows traumatic injury to the spinal cord.
Collapse
Affiliation(s)
- Philip C Burcham
- Pharmacology and Anaesthesiology Unit, School of Medicine and Pharmacology, the University of Western Australia, Nedlands, WA 6009, Australia
| |
Collapse
|
14
|
|
15
|
Myung JK, Frischer T, Afjehi-Sadat L, Pollak A, Lubec G. Mass spectrometrical analysis of the processed metastasis-inducing anterior gradient protein 2 homolog reveals 100% sequence coverage. Amino Acids 2007; 35:485-94. [PMID: 17497304 DOI: 10.1007/s00726-007-0551-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2007] [Accepted: 03/23/2007] [Indexed: 11/29/2022]
Abstract
Anterior gradient protein 2 homolog is a metastasis-inducing protein in a rat model of rat breast cancer and prognostic for outcome in hormonally treated breast cancer patients. Carrying out protein profiling in several mammalian cells and tissues, we detected this protein (synonym: secreted cement gland protein XAG-2 homolog) that was originally described in toad skin, in human bronchial epithelia. Tissues obtained from biopsies were homogenised and extracted proteins were run on two-dimensional gel electrophoresis. Following in-gel digestion with proteases trypsin, AspN, LysC and chymotrypsin, mass spectrometrical analysis was carried out by MALDI-TOF/TOF. The use of MS following multi-enzyme digestion of the protein resulted into 100% sequence coverage. MS/MS analysis enabled sequencing of 87% of the protein structure. This percentage does not include the signal peptide that was not observed in our protein due to processing. No posttranslational modifications were detectable and no sequence conflicts were observed. Complete analysis, unambiguous identification and characterisation of this biologically important protein could be shown, which is relevant for the definition of a marker protein that has been described so far by immunochemical methods only. Complete analysis is of importance as it forms the basis for all future work on this protein and, moreover, may serve as an analytical tool for further studies.
Collapse
Affiliation(s)
- J-K Myung
- Department of Pediatrics, Medical University of Vienna, Vienna, Austria
| | | | | | | | | |
Collapse
|