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Shang L, Huang JF, Ding W, Chen S, Xue LX, Ma RF, Xiong K. Calpain: a molecule to induce AIF-mediated necroptosis in RGC-5 following elevated hydrostatic pressure. BMC Neurosci 2014; 15:63. [PMID: 24884644 PMCID: PMC4023497 DOI: 10.1186/1471-2202-15-63] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2014] [Accepted: 04/28/2014] [Indexed: 01/28/2023] Open
Abstract
BACKGROUND RIP3 (Receptor-interacting protein 3) pathway was mainly described as the molecular mechanism of necroptosis (programmed necrosis). But recently, non-RIP3 pathways were found to mediate necroptosis. We deliberate to investigate the effect of calpain, a molecule to induce necroptosis as reported (Cell Death Differ 19:245-256, 2012), in RGC-5 following elevated hydrostatic pressure. RESULTS First, we identified the existence of necroptosis of RGC-5 after insult by using necrostatin-1 (Nec-1, necroptosis inhibitor) detected by flow cytometry. Immunofluorescence staining and western blot were used to detect the expression of calpain. Western blot analysis was carried out to describe the truncated AIF (tAIF) expression with or without pretreatment of ALLN (calpain activity inhibitor). Following elevated hydrostatic pressure, necroptotic cells pretreated with or without ALLN was stained by Annexin V/PI, The activity of calpain was also examined to confirm the inhibition effect of ALLN. The results showed that after cell injury there was an upregulation of calpain expression. Upon adding ALLN, the calpain activity was inhibited, and tAIF production was reduced upon injury along with the decreased number of necroptosis cells. CONCLUSION Our study found that calpain may induce necroptosis via tAIF-modulation in RGC-5 following elevated hydrostatic pressure.
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Affiliation(s)
- Lei Shang
- Department of Anatomy and Neurobiology, Central South University School of Basic Medical Sciences, 172 Tongzi Po Road, 410013 Changsha, Hunan, China
| | - Ju-Fang Huang
- Department of Anatomy and Neurobiology, Central South University School of Basic Medical Sciences, 172 Tongzi Po Road, 410013 Changsha, Hunan, China
| | - Wei Ding
- Department of Anatomy and Neurobiology, Central South University School of Basic Medical Sciences, 172 Tongzi Po Road, 410013 Changsha, Hunan, China
| | - Shuang Chen
- Department of Anatomy and Neurobiology, Central South University School of Basic Medical Sciences, 172 Tongzi Po Road, 410013 Changsha, Hunan, China
| | - Li-Xiang Xue
- Department of Biochemistry and Molecular Biology, Peking University Health Science Center, 100191 Beijing, China
| | - Ruo-Fei Ma
- Xiangya School of Medicine, Central South University, 410013 Changsha, Hunan, China
| | - Kun Xiong
- Department of Anatomy and Neurobiology, Central South University School of Basic Medical Sciences, 172 Tongzi Po Road, 410013 Changsha, Hunan, China
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52
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Non-invasive detection of early retinal neuronal degeneration by ultrahigh resolution optical coherence tomography. PLoS One 2014; 9:e93916. [PMID: 24776961 PMCID: PMC4002422 DOI: 10.1371/journal.pone.0093916] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2013] [Accepted: 03/12/2014] [Indexed: 12/20/2022] Open
Abstract
Optical coherence tomography (OCT) has revolutionises the diagnosis of retinal disease based on the detection of microscopic rather than subcellular changes in retinal anatomy. However, currently the technique is limited to the detection of microscopic rather than subcellular changes in retinal anatomy. However, coherence based imaging is extremely sensitive to both changes in optical contrast and cellular events at the micrometer scale, and can generate subtle changes in the spectral content of the OCT image. Here we test the hypothesis that OCT image speckle (image texture) contains information regarding otherwise unresolvable features such as organelle changes arising in the early stages of neuronal degeneration. Using ultrahigh resolution (UHR) OCT imaging at 800 nm (spectral width 140 nm) we developed a robust method of OCT image analyses, based on spatial wavelet and texture-based parameterisation of the image speckle pattern. For the first time we show that this approach allows the non-invasive detection and quantification of early apoptotic changes in neurons within 30 min of neuronal trauma sufficient to result in apoptosis. We show a positive correlation between immunofluorescent labelling of mitochondria (a potential source of changes in cellular optical contrast) with changes in the texture of the OCT images of cultured neurons. Moreover, similar changes in optical contrast were also seen in the retinal ganglion cell- inner plexiform layer in retinal explants following optic nerve transection. The optical clarity of the explants was maintained throughout in the absence of histologically detectable change. Our data suggest that UHR OCT can be used for the non-invasive quantitative assessment of neuronal health, with a particular application to the assessment of early retinal disease.
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53
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Liu M, Guo L, Salt TE, Cordeiro MF. Dendritic changes in rat visual pathway associated with experimental ocular hypertension. Curr Eye Res 2014; 39:953-63. [PMID: 24754236 DOI: 10.3109/02713683.2014.884594] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
PURPOSE Increasing evidence shows that structural changes in dendrites play an important role in neuronal degenerative processes. The aims of this study were to characterize and delineate morphological changes of dendrites in retinal ganglion cells (RGCs) and their central target neurons in the superior colliculus (SC) and lateral geniculate nucleus (LGN) in experimental rat glaucoma. METHODS Chronic ocular hypertension (OHT) was surgically induced in rats and animals were sacrificed at 1, 4, 8, 16 and 32 weeks following IOP elevation. Animals without IOP elevation served as normal control. Dendritic morphology of neurons was visualized by ex vivo DiI labelling using confocal microscopy and dendritic length and number was quantified using Image J. RESULTS We found significant dendritic shrinkage (p < 0.001) and loss (p < 0.001) in RGCs and neurons in the SC and LGN in OHT animals compared to age-matched controls. Analysis of the temporal morphological profiles among them revealed the RGCs to have the earliest changes compared to the SC and LGN although the most prominent changes occurred in the SC. CONCLUSION Our study has demonstrated that OHT results in dendritic changes of the neurons throughout the visual pathways, from RGCs to SC cells and LGN cells, suggesting that both the retina and the brain should be targeted when considering diagnosis and therapeutic strategies for glaucoma.
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Affiliation(s)
- Meng Liu
- Glaucoma and Retinal Neurodegeneration Research Group, UCL Institute of Ophthalmology , London , United Kingdom
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54
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Butt GF, Habib A, Mahgoub K, Sofela A, Tilley M, Guo L, Cordeiro MF. Optic nerve regeneration. EXPERT REVIEW OF OPHTHALMOLOGY 2014. [DOI: 10.1586/eop.12.66] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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55
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Maresca A, la Morgia C, Caporali L, Valentino ML, Carelli V. The optic nerve: a "mito-window" on mitochondrial neurodegeneration. Mol Cell Neurosci 2013; 55:62-76. [PMID: 22960139 PMCID: PMC3629569 DOI: 10.1016/j.mcn.2012.08.004] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2012] [Revised: 07/27/2012] [Accepted: 08/06/2012] [Indexed: 01/16/2023] Open
Abstract
Retinal ganglion cells (RGCs) project their long axons, composing the optic nerve, to the brain, transmitting the visual information gathered by the retina, ultimately leading to formed vision in the visual cortex. The RGC cellular system, representing the anterior part of the visual pathway, is vulnerable to mitochondrial dysfunction and optic atrophy is a very frequent feature of mitochondrial and neurodegenerative diseases. The start of the molecular era of mitochondrial medicine, the year 1988, was marked by the identification of a maternally inherited form of optic atrophy, Leber's hereditary optic neuropathy, as the first disease due to mitochondrial DNA point mutations. The field of mitochondrial medicine has expanded enormously over the last two decades and many neurodegenerative diseases are now known to have a primary mitochondrial etiology or mitochondrial dysfunction plays a relevant role in their pathogenic mechanism. Recent technical advancements in neuro-ophthalmology, such as optical coherence tomography, prompted a still ongoing systematic re-investigation of retinal and optic nerve involvement in neurodegenerative disorders. In addition to inherited optic neuropathies, such as Leber's hereditary optic neuropathy and dominant optic atrophy, and in addition to the syndromic mitochondrial encephalomyopathies or mitochondrial neurodegenerative disorders such as some spinocerebellar ataxias or familial spastic paraparesis and other disorders, we draw attention to the involvement of the optic nerve in classic age-related neurodegenerative disorders such as Parkinson and Alzheimer disease. We here provide an overview of optic nerve pathology in these different clinical settings, and we review the possible mechanisms involved in the pathogenesis of optic atrophy. This may be a model of general value for the field of neurodegeneration. This article is part of a Special Issue entitled 'Mitochondrial function and dysfunction in neurodegeneration'.
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Affiliation(s)
| | | | | | | | - Valerio Carelli
- Corresponding author at: IRCCS Institute of Neurological Sciences of Bologna, Department of Neurological Sciences, University of Bologna, Via Ugo Foscolo 7, 40123 Bologna, Italy. Fax: + 39 051 2092751.
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56
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Retinal ganglion cell dendritic degeneration in a mouse model of Alzheimer's disease. Neurobiol Aging 2013; 34:1799-806. [DOI: 10.1016/j.neurobiolaging.2013.01.006] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2012] [Revised: 01/11/2013] [Accepted: 01/11/2013] [Indexed: 12/30/2022]
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57
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Capozzi ME, Gordon AY, Penn JS, Jayagopal A. Molecular imaging of retinal disease. J Ocul Pharmacol Ther 2013; 29:275-86. [PMID: 23421501 DOI: 10.1089/jop.2012.0279] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Imaging of the eye plays an important role in ocular therapeutic discovery and evaluation in preclinical models and patients. Advances in ophthalmic imaging instrumentation have enabled visualization of the retina at an unprecedented resolution. These developments have contributed toward early detection of the disease, monitoring of disease progression, and assessment of the therapeutic response. These powerful technologies are being further harnessed for clinical applications by configuring instrumentation to detect disease biomarkers in the retina. These biomarkers can be detected either by measuring the intrinsic imaging contrast in tissue, or by the engineering of targeted injectable contrast agents for imaging of the retina at the cellular and molecular level. Such approaches have promise in providing a window on dynamic disease processes in the retina such as inflammation and apoptosis, enabling translation of biomarkers identified in preclinical and clinical studies into useful diagnostic targets. We discuss recently reported and emerging imaging strategies for visualizing diverse cell types and molecular mediators of the retina in vivo during health and disease, and the potential for clinical translation of these approaches.
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Affiliation(s)
- Megan E Capozzi
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN 37232-8808, USA
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58
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Sahaboglu A, Paquet-Durand O, Dietter J, Dengler K, Bernhard-Kurz S, Ekström PAR, Hitzmann B, Ueffing M, Paquet-Durand F. Retinitis pigmentosa: rapid neurodegeneration is governed by slow cell death mechanisms. Cell Death Dis 2013; 4:e488. [PMID: 23392176 PMCID: PMC3593146 DOI: 10.1038/cddis.2013.12] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2012] [Revised: 12/21/2012] [Accepted: 01/03/2013] [Indexed: 12/31/2022]
Abstract
For most neurodegenerative diseases the precise duration of an individual cell's death is unknown, which is an obstacle when counteractive measures are being considered. To address this, we used the rd1 mouse model for retinal neurodegeneration, characterized by phosphodiesterase-6 (PDE6) dysfunction and photoreceptor death triggered by high cyclic guanosine-mono-phosphate (cGMP) levels. Using cellular data on cGMP accumulation, cell death, and survival, we created mathematical models to simulate the temporal development of the degeneration. We validated model predictions using organotypic retinal explant cultures derived from wild-type animals and exposed to the selective PDE6 inhibitor zaprinast. Together, photoreceptor data and modeling for the first time delineated three major cell death phases in a complex neuronal tissue: (1) initiation, taking up to 36 h, (2) execution, lasting another 40 h, and finally (3) clearance, lasting about 7 h. Surprisingly, photoreceptor neurodegeneration was noticeably slower than necrosis or apoptosis, suggesting a different mechanism of death for these neurons.
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Affiliation(s)
- A Sahaboglu
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
| | - O Paquet-Durand
- Institute of Food Science and Biotechnology, University of Stuttgart Hohenheim, Stuttgart, Germany
| | - J Dietter
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
| | - K Dengler
- Skin Clinic, University of Tübingen, Tübingen, Germany
| | - S Bernhard-Kurz
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
| | - P AR Ekström
- Department of Clinical Sciences, Lund, University of Lund, Lund, Sweden
| | - B Hitzmann
- Institute of Food Science and Biotechnology, University of Stuttgart Hohenheim, Stuttgart, Germany
| | - M Ueffing
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
| | - F Paquet-Durand
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
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59
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The potential of annexin-labelling for the diagnosis and follow-up of glaucoma. Cell Tissue Res 2013; 353:279-85. [DOI: 10.1007/s00441-013-1554-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2012] [Accepted: 01/03/2013] [Indexed: 01/04/2023]
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60
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Abbott CJ, Choe TE, Lusardi TA, Burgoyne CF, Wang L, Fortune B. Imaging axonal transport in the rat visual pathway. BIOMEDICAL OPTICS EXPRESS 2013; 4:364-386. [PMID: 23412846 PMCID: PMC3567722 DOI: 10.1364/boe.4.000364] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/19/2012] [Revised: 01/10/2013] [Accepted: 01/28/2013] [Indexed: 06/01/2023]
Abstract
A technique was developed for assaying axonal transport in retinal ganglion cells using 2 µl injections of 1% cholera toxin b-subunit conjugated to AlexaFluor488 (CTB). In vivo retinal and post-mortem brain imaging by confocal scanning laser ophthalmoscopy and post-mortem microscopy were performed. The transport of CTB was sensitive to colchicine, which disrupts axonal microtubules. The bulk rates of transport were determined to be approximately 80-90 mm/day (anterograde) and 160 mm/day (retrograde). Results demonstrate that axonal transport of CTB can be monitored in vivo in the rodent anterior visual pathway, is dependent on intact microtubules, and occurs by active transport mechanisms.
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Affiliation(s)
- Carla J. Abbott
- Discoveries in Sight Research Laboratories, Devers Eye Institute, and
Legacy Research Institute, Legacy Health, Portland, OR 97232, USA
| | - Tiffany E. Choe
- Discoveries in Sight Research Laboratories, Devers Eye Institute, and
Legacy Research Institute, Legacy Health, Portland, OR 97232, USA
| | - Theresa A. Lusardi
- R.S. Dow Neurobiology Laboratories, Legacy Research Institute, Legacy
Health, Portland, OR 97232, USA
| | - Claude F. Burgoyne
- Discoveries in Sight Research Laboratories, Devers Eye Institute, and
Legacy Research Institute, Legacy Health, Portland, OR 97232, USA
| | - Lin Wang
- Discoveries in Sight Research Laboratories, Devers Eye Institute, and
Legacy Research Institute, Legacy Health, Portland, OR 97232, USA
| | - Brad Fortune
- Discoveries in Sight Research Laboratories, Devers Eye Institute, and
Legacy Research Institute, Legacy Health, Portland, OR 97232, USA
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61
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Abstract
Since the initial description of apoptosis, a number of different forms of cell death have been described. In this review we will focus on classic caspase-dependent apoptosis and its variations that contribute to diseases. Over fifty years of research have clarified molecular mechanisms involved in apoptotic signaling as well and shown that alterations of these pathways lead to human diseases. Indeed both reduced and increased apoptosis can result in pathology. More recently these findings have led to the development of therapeutic approaches based on regulation of apoptosis, some of which are in clinical trials or have entered medical practice.
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Affiliation(s)
- Bartolo Favaloro
- Dipartimento di Scienze Biomediche, Universita' "G. d'Annunzio" Chieti-Pescara, Italy
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62
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Sabirzhanov B, Stoica BA, Hanscom M, Piao CS, Faden AI. Over-expression of HSP70 attenuates caspase-dependent and caspase-independent pathways and inhibits neuronal apoptosis. J Neurochem 2012; 123:542-54. [PMID: 22909049 DOI: 10.1111/j.1471-4159.2012.07927.x] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2012] [Revised: 08/13/2012] [Accepted: 08/14/2012] [Indexed: 01/22/2023]
Abstract
HSP70 is a member of the family of heat-shock proteins that are known to be up-regulated in neurons following injury and/or stress. HSP70 over-expression has been linked to neuroprotection in multiple models, including neurodegenerative disorders. In contrast, less is known about the neuroprotective effects of HSP70 in neuronal apoptosis and with regard to modulation of programmed cell death (PCD) mechanisms in neurons. We examined the effects of HSP70 over-expression by transfection with HSP70-expression plasmids in primary cortical neurons and the SH-SY5Y neuronal cell line using four independent models of apoptosis: etoposide, staurosporine, C2-ceramide, and β-Amyloid. In these apoptotic models, neurons transfected with the HSP70 construct showed significantly reduced induction of nuclear apoptotic markers and/or cell death. Furthermore, we demonstrated that HSP70 binds and potentially inactivates Apoptotic protease-activating factor 1, as well as apoptosis-inducing factor, key molecules involved in development of caspase-dependent and caspase-independent PCD, respectively. Markers of caspase-dependent PCD, including active caspase-3, caspase-9, and cleaved PARP were attenuated in neurons over-expressing HSP70. These data indicate that HSP70 protects against neuronal apoptosis and suggest that these effects reflect, at least in part, to inhibition of both caspase-dependent and caspase-independent PCD pathways.
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Affiliation(s)
- Boris Sabirzhanov
- Department of Anesthesiology, Shock Trauma & Anesthesiology Research (STAR) Organized Research Center, University of Maryland School of Medicine, Baltimore, MD, USA.
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63
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Galvao J, Davis BM, Cordeiro MF. In vivo imaging of retinal ganglion cell apoptosis. Curr Opin Pharmacol 2012; 13:123-7. [PMID: 22995681 DOI: 10.1016/j.coph.2012.08.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2012] [Revised: 08/27/2012] [Accepted: 08/28/2012] [Indexed: 01/24/2023]
Abstract
Apoptosis, or programmed cell death, plays a vital role in normal development and ageing. However, dysregulation of this process is responsible for many disease states including; cancer, autoimmune and neurodegeneration. For this reason, in vivo visualisation of apoptosis may prove a useful tool for both laboratory research and clinical diagnostics. Glaucoma comprises a distinctive group of chronic optic neuropathies, characterised by the progressive loss of retinal ganglion cells (RGCs). Early diagnosis of glaucoma remains a clear and unmet need. Recently, there have been significant advances in the detection of apoptosis in vivo using fluorescent probes to visualise single RGCs undergoing apoptosis, specifically DARC (Detection of Apoptotic Retinal Cells) [1] and capQ technology [2(••)].
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Affiliation(s)
- Joana Galvao
- Glaucoma & Retinal Neurodegeneration Research Group, University College London, London EC1 V9EL, UK
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64
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Cao K, Farahi M, Dakanali M, Chang WM, Sigurdson CJ, Theodorakis EA, Yang J. Aminonaphthalene 2-cyanoacrylate (ANCA) probes fluorescently discriminate between amyloid-β and prion plaques in brain. J Am Chem Soc 2012; 134:17338-41. [PMID: 22866977 DOI: 10.1021/ja3063698] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
A major challenge for diagnosing and monitoring the progression of amyloid-based diseases is the capability to distinguish between amyloid deposits that are associated with related, but distinctly different, diseases. Here, we demonstrate that aminonaphthalenyl 2-cyanoacrylate-based probes can fluorescently discriminate between different types of amyloid deposits in brain. The discriminating capability of these molecular rotors is due to the stabilization of the ground versus excited states of these probes as a function of the polarity of their microenvironment (i.e., within the binding pocket on the amyloid). This property makes it possible, for the first time, to estimate the inherent static relative permittivity (ε(0)) of the binding pocket of each amyloid within tissue. The capability to selectively follow the deposition of specific amyloids in tissue may provide important information for therapeutic development that is not readily accessible from currently available technology.
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Affiliation(s)
- Kevin Cao
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093-0358, USA
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65
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Tucci P. Caloric restriction: is mammalian life extension linked to p53? Aging (Albany NY) 2012; 4:525-34. [PMID: 22983298 PMCID: PMC3461340 DOI: 10.18632/aging.100481] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2012] [Accepted: 08/21/2012] [Indexed: 12/21/2022]
Abstract
Caloric restriction, that is limiting food intake, is recognized in mammals as the best characterized and most reproducible strategy for extending lifespan, retarding physiological aging and delaying the onset of age-associated diseases. The aim of this mini review is to argue that p53 is the connection in the abilities of both the Sirt-1 pathway and the TOR pathway to impact on longevity of cells and organisms. This novel, lifespan regulating function of p53 may be evolutionarily more ancient than its relatively recent role in apoptosis and tumour suppression, and is likely to provide many new insights into lifespan modulation.
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Affiliation(s)
- Paola Tucci
- Medical Research Council, Toxicology Unit, Leicester University, Leicester LE1 9HN, UK.
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66
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Abstract
Although the adult human brain has a small number of neural stem cells, they are insufficient to repair the damaged brain to achieve significant functional recovery for neurodegenerative diseases and stroke. Stem cell therapy, by either enhancing endogenous neurogenesis, or transplanting stem cells, has been regarded as a promising solution. However, the harsh environment of the diseased brain posts a severe threat to the survival and correct differentiation of those new stem cells. Hormesis (or preconditioning, stress adaptation) is an adaptation mechanism by which cells or organisms are potentiated to survive an otherwise lethal condition, such as the harsh oxidative stress in the stroke brain. Stem cells treated by low levels of chemical, physical, or pharmacological stimuli have been shown to survive better in the neurodegenerative brain. Thus combining hormesis and stem cell therapy might improve the outcome for treatment of these diseases. In addition, since the cell death patterns and their underlying molecular mechanism may vary in different neurodegenerative diseases, even in different progression stages of the same disease, it is essential to design a suitable and optimum hormetic strategy that is tailored to the individual patient.
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Affiliation(s)
- Guanghu Wang
- Institute of Molecular Medicine and Genetics, Medical College of Georgia, Georgia Health Sciences University
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67
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Hamley IW. The Amyloid Beta Peptide: A Chemist’s Perspective. Role in Alzheimer’s and Fibrillization. Chem Rev 2012; 112:5147-92. [DOI: 10.1021/cr3000994] [Citation(s) in RCA: 670] [Impact Index Per Article: 55.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- I. W. Hamley
- Department
of Chemistry, University of Reading, Whiteknights, Reading RG6 6AD,
U.K
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68
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Chiu K, Chan TF, Wu A, Leung IYP, So KF, Chang RCC. Neurodegeneration of the retina in mouse models of Alzheimer's disease: what can we learn from the retina? AGE (DORDRECHT, NETHERLANDS) 2012; 34:633-49. [PMID: 21559868 PMCID: PMC3337933 DOI: 10.1007/s11357-011-9260-2] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/15/2011] [Accepted: 04/26/2011] [Indexed: 05/30/2023]
Abstract
Alzheimer's disease (AD) is an age-related progressive neurodegenerative disease commonly found among elderly. In addition to cognitive and behavioral deficits, vision abnormalities are prevalent in AD patients. Recent studies investigating retinal changes in AD double-transgenic mice have shown altered processing of amyloid precursor protein and accumulation of β-amyloid peptides in neurons of retinal ganglion cell layer (RGCL) and inner nuclear layer (INL). Apoptotic cells were also detected in the RGCL. Thus, the pathophysiological changes of retinas in AD patients are possibly resembled by AD transgenic models. The retina is a simple model of the brain in the sense that some pathological changes and therapeutic strategies from the retina may be observed or applicable to the brain. Furthermore, it is also possible to advance our understanding of pathological mechanisms in other retinal degenerative diseases. Therefore, studying AD-related retinal degeneration is a promising way for the investigation on (1) AD pathologies and therapies that would eventually benefit the brain and (2) cellular mechanisms in other retinal degenerations such as glaucoma and age-related macular degeneration. This review will highlight the efforts on retinal degenerative research using AD transgenic mouse models.
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Affiliation(s)
- Kin Chiu
- Laboratory of Neurodegenerative Diseases, Department of Anatomy, The University of Hong Kong, Pokfulam, Hong Kong China
| | - Tin-Fung Chan
- Laboratory of Neurodegenerative Diseases, Department of Anatomy, The University of Hong Kong, Pokfulam, Hong Kong China
| | - Andrew Wu
- Laboratory of Neurodegenerative Diseases, Department of Anatomy, The University of Hong Kong, Pokfulam, Hong Kong China
| | - Irene Yan-Pui Leung
- Laboratory of Neurodegenerative Diseases, Department of Anatomy, The University of Hong Kong, Pokfulam, Hong Kong China
| | - Kwok-Fai So
- Laboratory of Neurodegenerative Diseases, Department of Anatomy, The University of Hong Kong, Pokfulam, Hong Kong China
- Research Centre of Heart, Brain, Hormone and Healthy Aging, The University of Hong Kong, Pokfulam, Hong Kong China
- State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Rm. L1-49, Laboratory Block, Faculty of Medicine Building, 21 Sassoon Road, Pokfulam, Hong Kong China
| | - Raymond Chuen-Chung Chang
- Laboratory of Neurodegenerative Diseases, Department of Anatomy, The University of Hong Kong, Pokfulam, Hong Kong China
- Research Centre of Heart, Brain, Hormone and Healthy Aging, The University of Hong Kong, Pokfulam, Hong Kong China
- State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Rm. L1-49, Laboratory Block, Faculty of Medicine Building, 21 Sassoon Road, Pokfulam, Hong Kong China
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69
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Parnell M, Guo L, Abdi M, Cordeiro MF. Ocular manifestations of Alzheimer's disease in animal models. Int J Alzheimers Dis 2012; 2012:786494. [PMID: 22666623 PMCID: PMC3362039 DOI: 10.1155/2012/786494] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2012] [Accepted: 03/11/2012] [Indexed: 12/29/2022] Open
Abstract
Alzheimer's disease (AD) is the most common form of dementia, and the pathological changes of senile plaques (SPs) and neurofibrillary tangles (NFTs) in AD brains are well described. Clinically, a diagnosis remains a postmortem one, hampering both accurate and early diagnosis as well as research into potential new treatments. Visual deficits have long been noted in AD patients, and it is becoming increasingly apparent that histopathological changes already noted in the brain also occur in an extension of the brain; the retina. Due to the optically transparent nature of the eye, it is possible to image the retina at a cellular level noninvasively and thus potentially allow an earlier diagnosis as well as a way of monitoring progression and treatment effects. Transgenic animal models expressing amyloid precursor protein (APP) presenilin (PS) and tau mutations have been used successfully to recapitulate the pathological findings of AD in the brain. This paper will cover the ocular abnormalities that have been detected in these transgenic AD animal models.
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Affiliation(s)
- Miles Parnell
- Glaucoma & Retinal Neurodegeneration Research Group, Visual Neuroscience, UCL Institute of Ophthalmology, London EC1V 9EL, UK
- Sutton Eye Unit, Epsom and St. Helier NHS Trust, Cotswold Road, Sutton, Surry, London, UK
| | - Li Guo
- Glaucoma & Retinal Neurodegeneration Research Group, Visual Neuroscience, UCL Institute of Ophthalmology, London EC1V 9EL, UK
| | - Mohamed Abdi
- St. Georges Healthcare NHS Trust, Blackshaw Road, Tooting, London, UK
| | - M. Francesca Cordeiro
- Glaucoma & Retinal Neurodegeneration Research Group, Visual Neuroscience, UCL Institute of Ophthalmology, London EC1V 9EL, UK
- Western Eye Hospital, Imperial College Healthcare Trust, London, UK
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70
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Abstract
Frequently, low doses of toxins and other stressors not only are harmless but also activate an adaptive stress response that raise the resistance of the organism against high doses of the same agent. This phenomenon, which is known as "hormesis", is best represented by ischemic preconditioning, the situation in which short ischemic episodes protect the brain and the heart against prolonged shortage of oxygen and nutrients. Many molecules that cause cell death also elicit autophagy, a cytoprotective mechanism relying on the digestion of potentially harmful intracellular structures, notably mitochondria. When high doses of these agents are employed, cells undergo mitochondrial outer membrane permeabilization and die. In contrast, low doses of such cytotoxic agents can activate hormesis in several paradigms, and this may explain the lifespan-prolonging potential of autophagy inducers including resveratrol and caloric restriction.
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71
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Bucur O, Stancu AL, Khosravi-Far R, Almasan A. Analysis of apoptosis methods recently used in Cancer Research and Cell Death & Disease publications. Cell Death Dis 2012; 3:e263. [PMID: 22297295 PMCID: PMC3288344 DOI: 10.1038/cddis.2012.2] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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72
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Abstract
Primary open angle glaucoma and Alzheimer’s disease have long been established as two separate pathological entities, primarily affecting the elderly. The progressive, irreversible course of both diseases has significant implications on an aging population. As the complex pathophysiology of the two diseases has progressively unraveled over the past two decades, common pathophysiological changes have also been elucidated. Some of these mechanisms have established a strong grounding, whilst others remain principally speculative. The mutual neuropathological changes in primary open angle glaucoma and Alzheimer’s disease have facilitated the development of neuroprotective strategies. While most of these strategies are still in the preclinical phase, they have shown great promise in experimental animal studies. Further understanding of the common pathophysiology of primary open angle glaucoma and Alzheimer’s disease and their timeline may have great implications on early diagnosis and effective therapeutic targeting.
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Affiliation(s)
- Mukhtar Bizrah
- Glaucoma & Retinal Neurodegeneration Research Group, Visual Neuroscience, UCL Institute of Ophthalmology, London, UK; Western Eye Hospital, Imperial College Healthcare Trust, London, UK
- Guy’s & St Thomas’ NHS Foundation Trust, London, UK
| | - Li Guo
- Glaucoma & Retinal Neurodegeneration Research Group, Visual Neuroscience, UCL Institute of Ophthalmology, London, UK; Western Eye Hospital, Imperial College Healthcare Trust, London, UK
| | - Maria Francesca Cordeiro
- Glaucoma & Retinal Neurodegeneration Research Group, Visual Neuroscience, UCL Institute of Ophthalmology, London, UK; Western Eye Hospital, Imperial College Healthcare Trust, London, UK
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73
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Cell death pathology: cross-talk with autophagy and its clinical implications. Biochem Biophys Res Commun 2011; 414:277-81. [PMID: 21963447 DOI: 10.1016/j.bbrc.2011.09.080] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2011] [Accepted: 09/14/2011] [Indexed: 12/12/2022]
Abstract
Autophagy is a self-digesting mechanism that cells adopt to respond to stressful stimuli. Morphologically, cells dying by autophagy show multiple cytoplasmic double-membraned vacuoles, and, if prolonged, autophagy can lead to cell death, "autophagic cell death". Thus, autophagy can act both as a temporary protective mechanism during a brief stressful episode and be a mode of cell death in its own right. In this mini-review we focus on recent knowledge concerning the connection between autophagy and programmed cell death, evaluating their possible implications for therapy in pathologies like cancer and neurodegeneration.
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74
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LEMA C, VARELA-RAMIREZ A, AGUILERA RJ. Differential nuclear staining assay for high-throughput screening to identify cytotoxic compounds. CURRENT CELLULAR BIOCHEMISTRY 2011; 1:1-14. [PMID: 27042697 PMCID: PMC4816492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
As large quantities of novel synthetic molecules continue to be generated there is a challenge to identify therapeutic agents with cytotoxic activity. Here we introduce a Differential Nuclear Staining (DNS) assay adapted to live-cell imaging for high throughput screening (HTS) that utilizes two fluorescent DNA intercalators, Hoechst 33342 and Propidium iodide (PI). Since Hoechst can readily cross cell membranes to stain DNA of living and dead cells, it was used to label the total number of cells. In contrast, PI only enters cells with compromised plasma membranes, thus selectively labeling dead cells. The DNS assay was successfully validated by utilizing well known cytotoxic agents with fast or slow cytotoxic activities. The assay was found to be suitable for HTS with Z' factors ranging from 0.86 to 0.60 for 96 and 384-well formats, respectively. Furthermore, besides plate-to-plate reproducibility, assay quality performance was evaluated by determining ratios of signal-to-noise and signal-to-background, as well as coefficient of variation, which resulted in adequate values and validated the assay for HTS initiatives. As proof of concept, eighty structurally diverse compounds from a small molecule library were screened in a 96-well plate format using the DNS assay. Using this DNS assay, six hits with cytotoxic properties were identified and all of them were also successfully identified by using the commercially available MTS assay (CellTiter 96® Cell Proliferation Assay). In addition, the DNS and a flow cytometry assay were used to validate the activity of the cytotoxic compounds. The DNS assay was also used to generate dose-response curves and to obtain CC50 values. The results indicate that the DNS assay is reliable and robust and suitable for primary and secondary screens of compounds with potential cytotoxic activity.
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Affiliation(s)
- Carolina LEMA
- University of Texas at El Paso, Department of Biological Sciences, Bioscience Research Building, 500 West University Ave. El Paso, Texas 79968-0519, USA
| | - Armando VARELA-RAMIREZ
- University of Texas at El Paso, Department of Biological Sciences, Bioscience Research Building, 500 West University Ave. El Paso, Texas 79968-0519, USA
| | - Renato J. AGUILERA
- University of Texas at El Paso, Department of Biological Sciences, Bioscience Research Building, 500 West University Ave. El Paso, Texas 79968-0519, USA
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75
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Abstract
The strong interest in cell death, and the shift in emphasis from basic mechanisms to translational aspects fostered the launch last year of the new sister journal of Cell Death and Differentiation, named Cell Death and Disease, to reflect its stronger focus towards clinical applications. Here, we review that first year of activity, which reflects an enthusiastic response by the scientific community. On the basis of this, we now launch two novel initiatives, the start of a new section dedicated to cancer metabolism and the opening of a new editorial office in Shanghai.
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76
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Dasari B, Prasanthi JRP, Marwarha G, Singh BB, Ghribi O. Cholesterol-enriched diet causes age-related macular degeneration-like pathology in rabbit retina. BMC Ophthalmol 2011; 11:22. [PMID: 21851605 PMCID: PMC3170645 DOI: 10.1186/1471-2415-11-22] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2011] [Accepted: 08/18/2011] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Alzheimer's disease (AD) and age-related macular degeneration (AMD) share several pathological hallmarks including β-amyloid (Aβ) accumulation, oxidative stress, and apoptotic cell death. The causes of AD and AMD are likely multi-factorial with several factors such as diet, environment, and genetic susceptibility participating in the pathogenesis of these diseases. Epidemiological studies correlated high plasma cholesterol levels with high incidence of AD, and feeding rabbits with a diet rich in cholesterol has been shown to induce AD-like pathology in rabbit brain. High intake of cholesterol and saturated fat were also long been suspected to increase the risk for AMD. However, the extent to which cholesterol-enriched diet may also cause AMD-like features in rabbit retinas is not well known. METHODS Male New Zealand white rabbits were fed normal chow or a 2% cholesterol-enriched diet for 12 weeks. At necropsy, animals were perfused with Dulbecco's phosphate-buffered saline and the eyes were promptly removed. One eye of each animal was used for immunohistochemistry and retina dissected from the other eye was used for Western blot, ELISA assays, spectrophotometry and mass spectrometry analyses. RESULTS Increased levels of Aβ, decreased levels of the anti-apoptotic protein Bcl-2, increased levels of the pro-apoptotic Bax and gadd153 proteins, emergence of TUNEL-positive cells, and increased generation of reactive oxygen species were found in retinas from cholesterol-fed compared to normal chow-fed rabbits. Additionally, astrogliosis, drusen-like debris and cholesterol accumulations in retinas from cholesterol-fed rabbits were observed. As several lines of evidence suggest that oxidized cholesterol metabolites (oxysterols) may be the link by which cholesterol contributes to the pathogenesis of AMD, we determined levels of oxysterols and found a dramatic increase in levels of oxysterols in retinas from cholesterol-fed rabbits. CONCLUSIONS Our results suggest that cholesterol-enriched diets cause retinal degeneration that is relevant to AMD. Furthermore, our data suggests high cholesterol levels and subsequent increase in the cholesterol metabolites as potential culprits to AMD.
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Affiliation(s)
- Bhanu Dasari
- Department of Pharmacology, Physiology and Therapeutics, University of North Dakota School of Medicine and Health Sciences, Grand Forks, North Dakota, 58202, USA
| | - Jaya RP Prasanthi
- Department of Pharmacology, Physiology and Therapeutics, University of North Dakota School of Medicine and Health Sciences, Grand Forks, North Dakota, 58202, USA
| | - Gurdeep Marwarha
- Department of Pharmacology, Physiology and Therapeutics, University of North Dakota School of Medicine and Health Sciences, Grand Forks, North Dakota, 58202, USA
| | - Brij B Singh
- Department of Biochemistry and Molecular Biology, University of North Dakota School of Medicine and Health Sciences, Grand Forks, North Dakota, 58202, USA
| | - Othman Ghribi
- Department of Pharmacology, Physiology and Therapeutics, University of North Dakota School of Medicine and Health Sciences, Grand Forks, North Dakota, 58202, USA
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77
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Abstract
Apoptosis is a form of programmed cell death that is implicated in both pathological and physiological processes throughout the body. Its imaging in vivo with intravenous radiolabelled-annexin V has been heralded as an important advance, with around 30 clinical trials demonstrating its application in the early detection and monitoring of disease, and the assessment of efficacy of potential and existing therapies. A recent development has been the use of fluorescently labeled annexin V to visualize single retinal cells undergoing the process of apoptosis in vivo with ophthalmoscopy. This has been given the acronym DARC (Detection of Apoptosing Retinal Cells). DARC so far has only been used experimentally, but clinical trials are starting shortly in glaucoma patients. Results suggest that DARC may provide a direct assessment of retinal ganglion cell health. By enabling early assessment and quantitative analysis of cellular degeneration in glaucoma, it is hoped that DARC can identify patients before the onset of irreversible vision loss. Furthermore, in addition to aiding the tracking of disease, it may provide a rapid and objective assessment of potential and effective therapies, providing a new and meaningful clinical endpoint in glaucomatous disease that is so badly needed.
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78
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Schutters K, Reutelingsperger C. Phosphatidylserine targeting for diagnosis and treatment of human diseases. Apoptosis 2010; 15:1072-82. [PMID: 20440562 PMCID: PMC2929432 DOI: 10.1007/s10495-010-0503-y] [Citation(s) in RCA: 126] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Cells are able to execute apoptosis by activating series of specific biochemical reactions. One of the most prominent characteristics of cell death is the externalization of phosphatidylserine (PS), which in healthy cells resides predominantly in the inner leaflet of the plasma membrane. These features have made PS-externalization a well-explored phenomenon to image cell death for diagnostic purposes. In addition, it was demonstrated that under certain conditions viable cells express PS at their surface such as endothelial cells of tumor blood vessels, stressed tumor cells and hypoxic cardiomyocytes. Hence, PS has become a potential target for therapeutic strategies aiming at Targeted Drug Delivery. In this review we highlight the biomarker PS and various PS-binding compounds that have been employed to target PS for diagnostic purposes. We emphasize the 35 kD human protein annexin A5, that has been developed as a Molecular Imaging agent to measure cell death in vitro, and non-invasively in vivo in animal models and in patients with cardiovascular diseases and cancer. Recently focus has shifted from diagnostic towards therapeutic applications employing annexin A5 in strategies to deliver drugs to cells that express PS at their surface.
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Affiliation(s)
- Kristof Schutters
- Department of Biochemistry, Cardiovascular Research Institute Maastricht, Maastricht University, The Netherlands.
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79
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Koronyo-Hamaoui M, Koronyo Y, Ljubimov AV, Miller CA, Ko MK, Black KL, Schwartz M, Farkas DL. Identification of amyloid plaques in retinas from Alzheimer's patients and noninvasive in vivo optical imaging of retinal plaques in a mouse model. Neuroimage 2010; 54 Suppl 1:S204-17. [PMID: 20550967 DOI: 10.1016/j.neuroimage.2010.06.020] [Citation(s) in RCA: 440] [Impact Index Per Article: 31.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2010] [Revised: 06/04/2010] [Accepted: 06/07/2010] [Indexed: 01/10/2023] Open
Abstract
Noninvasive monitoring of β-amyloid (Aβ) plaques, the neuropathological hallmarks of Alzheimer's disease (AD), is critical for AD diagnosis and prognosis. Current visualization of Aβ plaques in brains of live patients and animal models is limited in specificity and resolution. The retina as an extension of the brain presents an appealing target for a live, noninvasive optical imaging of AD if disease pathology is manifested there. We identified retinal Aβ plaques in postmortem eyes from AD patients (n=8) and in suspected early stage cases (n=5), consistent with brain pathology and clinical reports; plaques were undetectable in age-matched non-AD individuals (n=5). In APP(SWE)/PS1(∆E9) transgenic mice (AD-Tg; n=18) but not in non-Tg wt mice (n=10), retinal Aβ plaques were detected following systemic administration of curcumin, a safe plaque-labeling fluorochrome. Moreover, retinal plaques were detectable earlier than in the brain and accumulated with disease progression. An immune-based therapy effective in reducing brain plaques, significantly reduced retinal Aβ plaque burden in immunized versus non-immunized AD mice (n=4 mice per group). In live AD-Tg mice (n=24), systemic administration of curcumin allowed noninvasive optical imaging of retinal Aβ plaques in vivo with high resolution and specificity; plaques were undetectable in non-Tg wt mice (n=11). Our discovery of Aβ specific plaques in retinas from AD patients, and the ability to noninvasively detect individual retinal plaques in live AD mice establish the basis for developing high-resolution optical imaging for early AD diagnosis, prognosis assessment and response to therapies.
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Affiliation(s)
- Maya Koronyo-Hamaoui
- Department of Neurosurgery and Maxine Dunitz Neurosurgical Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA.
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80
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Kanamori A, Catrinescu MM, Kanamori N, Mears KA, Beaubien R, Levin LA. Superoxide is an associated signal for apoptosis in axonal injury. Brain 2010; 133:2612-25. [PMID: 20495185 DOI: 10.1093/brain/awq105] [Citation(s) in RCA: 93] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Optic neuropathy is the leading cause of irreversible blindness, and a paradigm for central nervous system axonal disease. The primary event is damage to retinal ganglion cell axons, with subsequent death of the cell body by apoptosis. Trials of neuroprotection for these and other neuronal diseases have mostly failed, primarily because mechanisms of neuroprotection in animals do not necessarily translate to humans. We developed a methodology for imaging an intracellular transduction pathway that signals neuronal death in the living animal. Using longitudinal confocal scanning multilaser ophthalmoscopy, we identified the production of superoxide within retrograde-labelled rat retinal ganglion cells after optic nerve transection. Superoxide was visualized by real-time imaging of its reaction product with intravitreally administered hydroethidine and confirmed by differential spectroscopy of the specific product 2-hydroxyethidium. Retinal ganglion cell superoxide increased within 24 h after axotomy, peaking at 4 days, and was not observed in contralateral untransected eyes. The superoxide signal preceded phosphatidylserine externalization, indicating that superoxide generation was an early event and preceded apoptosis. Intravitreal pegylated superoxide dismutase blocked superoxide generation after axotomy and delayed retinal ganglion cell death. Together, these results are consistent with superoxide being an upstream signal for retinal ganglion cell apoptosis after optic nerve injury. Early detection of axonal injury with superoxide could serve as a predictive biomarker for patients with optic neuropathy.
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Affiliation(s)
- Akiyasu Kanamori
- Maisonneuve-Rosemont Hospital Research Centre and Department of Ophthalmology, University of Montreal, 5415 boul. de l'Assomption, Montréal, Quebec, Canada
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81
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Schutters K, Reutelingsperger C. Phosphatidylserine targeting for diagnosis and treatment of human diseases. Apoptosis 2010. [PMID: 20440562 DOI: 10.1007/s10495-010�0503-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Cells are able to execute apoptosis by activating series of specific biochemical reactions. One of the most prominent characteristics of cell death is the externalization of phosphatidylserine (PS), which in healthy cells resides predominantly in the inner leaflet of the plasma membrane. These features have made PS-externalization a well-explored phenomenon to image cell death for diagnostic purposes. In addition, it was demonstrated that under certain conditions viable cells express PS at their surface such as endothelial cells of tumor blood vessels, stressed tumor cells and hypoxic cardiomyocytes. Hence, PS has become a potential target for therapeutic strategies aiming at Targeted Drug Delivery. In this review we highlight the biomarker PS and various PS-binding compounds that have been employed to target PS for diagnostic purposes. We emphasize the 35 kD human protein annexin A5, that has been developed as a Molecular Imaging agent to measure cell death in vitro, and non-invasively in vivo in animal models and in patients with cardiovascular diseases and cancer. Recently focus has shifted from diagnostic towards therapeutic applications employing annexin A5 in strategies to deliver drugs to cells that express PS at their surface.
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Affiliation(s)
- Kristof Schutters
- Department of Biochemistry, Cardiovascular Research Institute Maastricht, Maastricht University, The Netherlands.
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