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Miao S, Fourgeaud L, Burrola PG, Stern S, Zhang Y, Happonen KE, Novak SW, Gage FH, Lemke G. Tyro3 promotes the maturation of glutamatergic synapses. Front Neurosci 2024; 18:1327423. [PMID: 38410160 PMCID: PMC10894971 DOI: 10.3389/fnins.2024.1327423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Accepted: 01/26/2024] [Indexed: 02/28/2024] Open
Abstract
The receptor tyrosine kinase Tyro3 is abundantly expressed in neurons of the neocortex, hippocampus, and striatum, but its role in these cells is unknown. We found that neuronal expression of this receptor was markedly up-regulated in the postnatal mouse neocortex immediately prior to the final development of glutamatergic synapses. In the absence of Tyro3, cortical and hippocampal synapses never completed end-stage differentiation and remained electrophysiologically and ultrastructurally immature. Tyro3-/- cortical neurons also exhibited diminished plasma membrane expression of the GluA2 subunits of AMPA-type glutamate receptors, which are essential to mature synaptic function. Correspondingly, GluA2 membrane insertion in wild-type neurons was stimulated by Gas6, a Tyro3 ligand widely expressed in the postnatal brain. Behaviorally, Tyro3-/- mice displayed learning enhancements in spatial recognition and fear-conditioning assays. Together, these results demonstrate that Tyro3 promotes the functional maturation of glutamatergic synapses by driving plasma membrane translocation of GluA2 AMPA receptor subunits.
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Affiliation(s)
- Sheng Miao
- Molecular Neurobiology Laboratory, The Salk Institute for Biological Studies, La Jolla, CA, United States
| | - Lawrence Fourgeaud
- Molecular Neurobiology Laboratory, The Salk Institute for Biological Studies, La Jolla, CA, United States
| | - Patrick G Burrola
- Molecular Neurobiology Laboratory, The Salk Institute for Biological Studies, La Jolla, CA, United States
| | - Shani Stern
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, CA, United States
- Sagol Department of Neurobiology, University of Haifa, Haifa, Israel
| | - Yuhan Zhang
- Division of Biological Sciences, University of California, San Diego, La Jolla, CA, United States
| | - Kaisa E Happonen
- Molecular Neurobiology Laboratory, The Salk Institute for Biological Studies, La Jolla, CA, United States
| | - Sammy Weiser Novak
- Waitt Advanced Biophotonics Laboratory, The Salk Institute for Biological Studies, La Jolla, CA, United States
| | - Fred H Gage
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, CA, United States
| | - Greg Lemke
- Molecular Neurobiology Laboratory, The Salk Institute for Biological Studies, La Jolla, CA, United States
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Yang F, Almasieh M, Levin LA. In Vivo Imaging of Secondary Neurodegeneration Associated With Phosphatidylserine Externalization Along Axotomized Axons. Invest Ophthalmol Vis Sci 2024; 65:24. [PMID: 38345553 PMCID: PMC10866172 DOI: 10.1167/iovs.65.2.24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Accepted: 12/11/2023] [Indexed: 02/15/2024] Open
Abstract
Purpose Axonal degeneration in acute and chronic disorders is well-characterized, comprising retrograde (proximal) and Wallerian (distal) degeneration, but the mechanism of propagation remains less understood. Methods Laser injury with a diode-pumped solid-state 532 nm laser was used to axotomize retinal ganglion cell axons. We used confocal in vivo imaging to demonstrate that phosphatidylserine externalization is a biomarker of early axonal degeneration after selective intraretinal axotomy. Results Quantitative dynamic analysis revealed that the rate of axonal degeneration was fastest within 40 minutes, then decreased exponentially afterwards. Axonal degeneration was constrained within the same axotomized axonal bundles. Remarkably, axon degeneration arising from the site of injury induced a secondary degeneration of distal normal axons. Conclusions Axonal degeneration in vivo is a progressive process associated with phosphatidylserine externalization, which can propagate not only along the axon but to adjacent uninjured axons. This finding has implications for acute and chronic neurodegenerative disorders associated with axonal injury.
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Affiliation(s)
- Fan Yang
- Department of Ophthalmology and Visual Sciences, McGill University, Montreal, Canada
| | - Mohammadali Almasieh
- Department of Ophthalmology and Visual Sciences, McGill University, Montreal, Canada
| | - Leonard A. Levin
- Department of Ophthalmology and Visual Sciences, McGill University, Montreal, Canada
- Department of Neurology and Neurosurgery, McGill University, Montreal, Canada
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Risner ML, Ribeiro M, McGrady NR, Kagitapalli BS, Chamling X, Zack DJ, Calkins DJ. Neutral sphingomyelinase inhibition promotes local and network degeneration in vitro and in vivo. Cell Commun Signal 2023; 21:305. [PMID: 37904133 PMCID: PMC10614343 DOI: 10.1186/s12964-023-01291-1] [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: 06/08/2023] [Accepted: 08/22/2023] [Indexed: 11/01/2023] Open
Abstract
BACKGROUND Cell-to-cell communication is vital for tissues to respond, adapt, and thrive in the prevailing milieu. Several mechanisms mediate intercellular signaling, including tunneling nanotubes, gap junctions, and extracellular vesicles (EV). Depending on local and systemic conditions, EVs may contain cargoes that promote survival, neuroprotection, or pathology. Our understanding of pathologic intercellular signaling has been bolstered by disease models using neurons derived from human pluripotent stems cells (hPSC). METHODS Here, we used hPSC-derived retinal ganglion cells (hRGC) and the mouse visual system to investigate the influence of modulating EV generation on intercellular trafficking and cell survival. We probed the impact of EV modulation on cell survival by decreasing the catabolism of sphingomyelin into ceramide through inhibition of neutral sphingomyelinase (nSMase), using GW4869. We assayed for cell survival in vitro by probing for annexin A5, phosphatidylserine, viable mitochondria, and mitochondrial reactive oxygen species. In vivo, we performed intraocular injections of GW4869 and measured RGC and superior colliculus neuron density and RGC anterograde axon transport. RESULTS Following twenty-four hours of dosing hRGCs with GW4869, we found that inhibition of nSMase decreased ceramide and enhanced GM1 ganglioside accumulation. This inhibition also reduced the density of small EVs, increased the density of large EVs, and enriched the pro-apoptotic protein, annexin A5. Reducing nSMase activity increased hRGC apoptosis initiation due to enhanced density and uptake of apoptotic particles, as identified by the annexin A5 binding phospholipid, phosphatidylserine. We assayed intercellular trafficking of mitochondria by developing a coculture system of GW4869-treated and naïve hRGCs. In treated cells, inhibition of nSMase reduced the number of viable mitochondria, while driving mitochondrial reactive oxygen species not only in treated, but also in naive hRGCs added in coculture. In mice, 20 days following a single intravitreal injection of GW4869, we found a significant loss of RGCs and their axonal recipient neurons in the superior colliculus. This followed a more dramatic reduction in anterograde RGC axon transport to the colliculus. CONCLUSION Overall, our data suggest that perturbing the physiologic catabolism of sphingomyelin by inhibiting nSMase reorganizes plasma membrane associated sphingolipids, alters the profile of neuron-generated EVs, and promotes neurodegeneration in vitro and in vivo by shifting the balance of pro-survival versus -degenerative EVs. Video Abstract.
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Affiliation(s)
- Michael L Risner
- Department of Ophthalmology and Visual Sciences, Vanderbilt Eye Institute, Vanderbilt University Medical Center, AA7103 MCN/VUIIS, 1161 21st Ave S., Nashville, TN, 37232, USA.
- Department of Foundational Medical Studies, Eye Research Center, Oakland University William Beaumont School of Medicine, 369 Dodge Hall, 118 Library Dr., Rochester, MI, 48309, USA.
| | - Marcio Ribeiro
- Department of Ophthalmology and Visual Sciences, Vanderbilt Eye Institute, Vanderbilt University Medical Center, AA7103 MCN/VUIIS, 1161 21st Ave S., Nashville, TN, 37232, USA
| | - Nolan R McGrady
- Department of Ophthalmology and Visual Sciences, Vanderbilt Eye Institute, Vanderbilt University Medical Center, AA7103 MCN/VUIIS, 1161 21st Ave S., Nashville, TN, 37232, USA
| | - Bhanu S Kagitapalli
- Department of Ophthalmology and Visual Sciences, Vanderbilt Eye Institute, Vanderbilt University Medical Center, AA7103 MCN/VUIIS, 1161 21st Ave S., Nashville, TN, 37232, USA
| | - Xitiz Chamling
- Department of Ophthalmology, Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21287, USA
| | - Donald J Zack
- Department of Ophthalmology, Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21287, USA
| | - David J Calkins
- Department of Ophthalmology and Visual Sciences, Vanderbilt Eye Institute, Vanderbilt University Medical Center, AA7103 MCN/VUIIS, 1161 21st Ave S., Nashville, TN, 37232, USA.
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4
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Lieffrig SA, Gyimesi G, Mao Y, Finnemann SC. Clearance phagocytosis by the retinal pigment epithelial during photoreceptor outer segment renewal: Molecular mechanisms and relation to retinal inflammation. Immunol Rev 2023; 319:81-99. [PMID: 37555340 PMCID: PMC10615845 DOI: 10.1111/imr.13264] [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: 05/15/2023] [Accepted: 07/18/2023] [Indexed: 08/10/2023]
Abstract
Mammalian photoreceptor outer segment renewal is a highly coordinated process that hinges on timed cell signaling between photoreceptor neurons and the adjacent retinal pigment epithelial (RPE). It is a strictly rhythmic, synchronized process that underlies in part circadian regulation. We highlight findings from recently developed methods that quantify distinct phases of outer segment renewal in retinal tissue. At light onset, outer segments expose the conserved "eat-me" signal phosphatidylserine exclusively at their distal, most aged tip. A coordinated two-receptor efferocytosis process follows, in which ligands bridge outer segment phosphatidylserine with the RPE receptors αvβ5 integrin, inducing cytosolic signaling toward Rac1 and focal adhesion kinase/MERTK, and with MERTK directly, additionally inhibiting RhoA/ROCK and thus enabling F-actin dynamics favoring outer segment fragment engulfment. Photoreceptors and RPE persist for life with each RPE cell in the eye servicing dozens of overlying photoreceptors. Thus, RPE cells phagocytose more often and process more material than any other cell type. Mutant mice with impaired outer segment renewal largely retain functional photoreceptors and retinal integrity. However, when anti-inflammatory signaling in the RPE via MERTK or the related TYRO3 is lacking, catastrophic inflammation leads to immune cell infiltration that swiftly destroys the retina causing blindness.
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Affiliation(s)
- Stephanie A. Lieffrig
- Center for Cancer, Genetic Diseases and Gene Regulation, Department of Biological Sciences, Fordham University, Bronx, NY
| | - Gavin Gyimesi
- Center for Cancer, Genetic Diseases and Gene Regulation, Department of Biological Sciences, Fordham University, Bronx, NY
| | | | - Silvia C. Finnemann
- Center for Cancer, Genetic Diseases and Gene Regulation, Department of Biological Sciences, Fordham University, Bronx, NY
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Dirvelyte E, Bujanauskiene D, Jankaityte E, Daugelaviciene N, Kisieliute U, Nagula I, Budvytyte R, Neniskyte U. Genetically encoded phosphatidylserine biosensor for in vitro, ex vivo and in vivo labelling. Cell Mol Biol Lett 2023; 28:59. [PMID: 37501184 PMCID: PMC10373266 DOI: 10.1186/s11658-023-00472-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Accepted: 06/27/2023] [Indexed: 07/29/2023] Open
Abstract
BACKGROUND The dynamics of phosphatidylserine in the plasma membrane is a tightly regulated feature of eukaryotic cells. Phosphatidylserine (PS) is found preferentially in the inner leaflet of the plasma membrane. Disruption of this asymmetry leads to the exposure of phosphatidylserine on the cell surface and is associated with cell death, synaptic pruning, blood clotting and other cellular processes. Due to the role of phosphatidylserine in widespread cellular functions, an efficient phosphatidylserine probe is needed to study them. Currently, a few different phosphatidylserine labelling tools are available; however, these labels have unfavourable signal-to-noise ratios and are difficult to use in tissues due to limited permeability. Their application in living tissue requires injection procedures that damage the tissue and release damage-associated molecular patterns, which in turn stimulates phosphatidylserine exposure. METHODS For this reason, we developed a novel genetically encoded phosphatidylserine probe based on the C2 domain of the lactadherin (MFG-E8) protein, suitable for labelling exposed phosphatidylserine in various research models. We tested the C2 probe specificity to phosphatidylserine on hybrid bilayer lipid membranes by observing surface plasmon resonance angle shift. Then, we analysed purified fused C2 proteins on different cell culture lines or engineered AAVs encoding C2 probes on tissue cultures after apoptosis induction. For in vivo experiments, neurotropic AAVs were intravenously injected into perinatal mice, and after 2 weeks, brain slices were collected to observe C2-SNAP expression. RESULTS The biophysical analysis revealed the high specificity of the C2 probe for phosphatidylserine. The fused recombinant C2 proteins were suitable for labelling phosphatidylserine on the surface of apoptotic cells in various cell lines. We engineered AAVs and validated them in organotypic brain tissue cultures for non-invasive delivery of the genetically encoded C2 probe and showed that these probes were expressed in the brain in vivo after intravenous AAV delivery to mice. CONCLUSIONS We have demonstrated that the developed genetically encoded PS biosensor can be utilised in a variety of assays as a two-component system of C2 and C2m2 fusion proteins. This system allows for precise quantification and PS visualisation at directly specified threshold levels, enabling the evaluation of PS exposure in both physiological and cell death processes.
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Affiliation(s)
- Eimina Dirvelyte
- VU LSC-EMBL Partnership Institute for Genome Editing Technologies, Life Sciences Center, Vilnius University, Vilnius, Lithuania
| | - Daina Bujanauskiene
- VU LSC-EMBL Partnership Institute for Genome Editing Technologies, Life Sciences Center, Vilnius University, Vilnius, Lithuania
- Institute of Bioscience, Life Sciences Center, Vilnius University, Vilnius, Lithuania
| | - Evelina Jankaityte
- VU LSC-EMBL Partnership Institute for Genome Editing Technologies, Life Sciences Center, Vilnius University, Vilnius, Lithuania
- Institute of Biochemistry, Life Sciences Center, Vilnius University, Vilnius, Lithuania
| | - Neringa Daugelaviciene
- VU LSC-EMBL Partnership Institute for Genome Editing Technologies, Life Sciences Center, Vilnius University, Vilnius, Lithuania
| | - Ugne Kisieliute
- Institute of Bioscience, Life Sciences Center, Vilnius University, Vilnius, Lithuania
| | - Igor Nagula
- VU LSC-EMBL Partnership Institute for Genome Editing Technologies, Life Sciences Center, Vilnius University, Vilnius, Lithuania
| | - Rima Budvytyte
- VU LSC-EMBL Partnership Institute for Genome Editing Technologies, Life Sciences Center, Vilnius University, Vilnius, Lithuania
- Institute of Biochemistry, Life Sciences Center, Vilnius University, Vilnius, Lithuania
| | - Urte Neniskyte
- VU LSC-EMBL Partnership Institute for Genome Editing Technologies, Life Sciences Center, Vilnius University, Vilnius, Lithuania.
- Institute of Bioscience, Life Sciences Center, Vilnius University, Vilnius, Lithuania.
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Barth ND, Mendive‐Tapia L, Subiros‐Funosas R, Ghashghaei O, Lavilla R, Maiorino L, He X, Dransfield I, Egeblad M, Vendrell M. A Bivalent Activatable Fluorescent Probe for Screening and Intravital Imaging of Chemotherapy-Induced Cancer Cell Death. ANGEWANDTE CHEMIE (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2022; 134:e202113020. [PMID: 38505298 PMCID: PMC10947113 DOI: 10.1002/ange.202113020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Indexed: 11/11/2022]
Abstract
The detection and quantification of apoptotic cells is a key process in cancer research, particularly during the screening of anticancer therapeutics and in mechanistic studies using preclinical models. Intravital optical imaging enables high-resolution visualisation of cellular events in live organisms; however, there are few fluorescent probes that can reliably provide functional readouts in situ without interference from tissue autofluorescence. We report the design and optimisation of the fluorogenic probe Apotracker Red for real-time detection of cancer cell death. The strong fluorogenic behaviour, high selectivity, and excellent stability of Apotracker Red make it a reliable optical reporter for the characterisation of the effects of anticancer drugs in cells in vitro and for direct imaging of chemotherapy-induced apoptosis in vivo in mouse models of breast cancer.
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Affiliation(s)
- Nicole D. Barth
- Centre for Inflammation ResearchThe University of EdinburghUK
| | | | | | - Ouldouz Ghashghaei
- Laboratory of Medicinal ChemistryFaculty of Pharmacy and Institute of Biomedicine (IBUB)University of BarcelonaSpain
| | - Rodolfo Lavilla
- Laboratory of Medicinal ChemistryFaculty of Pharmacy and Institute of Biomedicine (IBUB)University of BarcelonaSpain
| | - Laura Maiorino
- Cold Spring Harbor LaboratoryCold Spring HarborNY11724USA
| | - Xue‐Yan He
- Cold Spring Harbor LaboratoryCold Spring HarborNY11724USA
| | - Ian Dransfield
- Centre for Inflammation ResearchThe University of EdinburghUK
| | - Mikala Egeblad
- Cold Spring Harbor LaboratoryCold Spring HarborNY11724USA
| | - Marc Vendrell
- Centre for Inflammation ResearchThe University of EdinburghUK
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7
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NeuroD1 induces microglial apoptosis and cannot induce microglia-to-neuron cross-lineage reprogramming. Neuron 2021; 109:4094-4108.e5. [PMID: 34875233 DOI: 10.1016/j.neuron.2021.11.008] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 06/28/2021] [Accepted: 09/24/2021] [Indexed: 11/21/2022]
Abstract
The regenerative capacity of neurons is limited in the central nervous system (CNS), with irreversible neuronal loss upon insult. In contrast, microglia exhibit extraordinary capacity for repopulation. Matsuda et al. (2019) recently reported NeuroD1-induced microglia-to-neuron conversion, aiming to provide an "unlimited" source to regenerate neurons. However, the extent to which NeuroD1 can exert cross-lineage reprogramming of microglia (myeloid lineage) to neurons (neuroectodermal lineage) is unclear. In this study, we unexpectedly found that NeuroD1 cannot convert microglia to neurons in mice. Instead, NeuroD1 expression induces microglial cell death. Moreover, lineage tracing reveals non-specific leakage of similar lentiviruses as previously used for microglia-to-neuron conversion, which confounds the microglia-to-neuron observation. In summary, we demonstrated that NeuroD1 cannot induce microglia-to-neuron cross-lineage reprogramming. We here propose rigid principles for verifying glia-to-neuron conversion. This Matters Arising paper is in response to Matsuda et al. (2019), published in Neuron.
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8
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Barth N, Mendive-Tapia L, Subiros-Funosas R, Ghashghaie O, Lavilla R, Maiorino L, He XY, Dransfield I, Egeblad M, Vendrell M. A Bivalent Activatable Fluorescent Probe for Screening and Intravital Imaging of Chemotherapy-induced Cancer Cell Death. Angew Chem Int Ed Engl 2021; 61:e202113020. [PMID: 34762762 PMCID: PMC8991960 DOI: 10.1002/anie.202113020] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Indexed: 11/21/2022]
Abstract
The detection and quantification of apoptotic cells is a key process in cancer research, particularly during the screening of anticancer therapeutics and in mechanistic studies using preclinical models. Intravital optical imaging enables high‐resolution visualisation of cellular events in live organisms; however, there are few fluorescent probes that can reliably provide functional readouts in situ without interference from tissue autofluorescence. We report the design and optimisation of the fluorogenic probe Apotracker Red for real‐time detection of cancer cell death. The strong fluorogenic behaviour, high selectivity, and excellent stability of Apotracker Red make it a reliable optical reporter for the characterisation of the effects of anticancer drugs in cells in vitro and for direct imaging of chemotherapy‐induced apoptosis in vivo in mouse models of breast cancer.
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Affiliation(s)
- Nicole Barth
- The University of Edinburgh, Centre for Inflammation Research, UNITED KINGDOM
| | | | | | - Ouldouz Ghashghaie
- University of Barcelona: Universitat de Barcelona, Faculty of Pharmacy, SPAIN
| | - Rodolfo Lavilla
- University of Barcelona: Universitat de Barcelona, Faculty of Pharmacy, UNITED KINGDOM
| | - Laura Maiorino
- Cold Spring Harbor Laboratory, Cold Spring Harbor Laboratory, UNITED STATES
| | - Xue-Yan He
- Cold Spring Harbor Laboratory, Cold Spring Harbor Laboratory, UNITED STATES
| | - Ian Dransfield
- The University of Edinburgh, Centre for inflammation research, UNITED KINGDOM
| | - Mikala Egeblad
- Cold Spring Harbor Laboratory, Cold Spring Harbor Laboratory, UNITED STATES
| | - Marc Vendrell
- University of Edinburgh, Centre for Inflammation Research, 47 Little France Crescent, EH16 4TJ, Edinburgh, UNITED KINGDOM
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9
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Li T, Yu D, Oak HC, Zhu B, Wang L, Jiang X, Molday RS, Kriegstein A, Piao X. Phospholipid-flippase chaperone CDC50A is required for synapse maintenance by regulating phosphatidylserine exposure. EMBO J 2021; 40:e107915. [PMID: 34585770 PMCID: PMC8561630 DOI: 10.15252/embj.2021107915] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 08/25/2021] [Accepted: 09/01/2021] [Indexed: 12/13/2022] Open
Abstract
Synaptic refinement is a critical physiological process that removes excess synapses to establish and maintain functional neuronal circuits. Recent studies have shown that focal exposure of phosphatidylserine (PS) on synapses acts as an "eat me" signal to mediate synaptic pruning. However, the molecular mechanism underlying PS externalization at synapses remains elusive. Here, we find that murine CDC50A, a chaperone of phospholipid flippases, localizes to synapses, and that its expression depends on neuronal activity. Cdc50a knockdown leads to phosphatidylserine exposure at synapses and subsequent erroneous synapse removal by microglia partly via the GPR56 pathway. Taken together, our data support that CDC50A safeguards synapse maintenance by regulating focal phosphatidylserine exposure at synapses.
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Affiliation(s)
- Tao Li
- Weill Institute for NeuroscienceUniversity of California, San Francisco (UCSF)San FranciscoCAUSA
- Newborn Brain Research InstituteUniversity of California, San Francisco (UCSF)San FranciscoCAUSA
| | - Diankun Yu
- Weill Institute for NeuroscienceUniversity of California, San Francisco (UCSF)San FranciscoCAUSA
- Newborn Brain Research InstituteUniversity of California, San Francisco (UCSF)San FranciscoCAUSA
| | - Hayeon C Oak
- Weill Institute for NeuroscienceUniversity of California, San Francisco (UCSF)San FranciscoCAUSA
- Newborn Brain Research InstituteUniversity of California, San Francisco (UCSF)San FranciscoCAUSA
| | - Beika Zhu
- Weill Institute for NeuroscienceUniversity of California, San Francisco (UCSF)San FranciscoCAUSA
- Newborn Brain Research InstituteUniversity of California, San Francisco (UCSF)San FranciscoCAUSA
| | - Li Wang
- Weill Institute for NeuroscienceUniversity of California, San Francisco (UCSF)San FranciscoCAUSA
- Department of NeurologyUniversity of California, San FranciscoSan FranciscoCAUSA
| | - Xueqiao Jiang
- Weill Institute for NeuroscienceUniversity of California, San Francisco (UCSF)San FranciscoCAUSA
- Newborn Brain Research InstituteUniversity of California, San Francisco (UCSF)San FranciscoCAUSA
| | - Robert S Molday
- Department of Biochemistry and Molecular BiologyUniversity of British ColumbiaVancouverBCCanada
| | - Arnold Kriegstein
- Weill Institute for NeuroscienceUniversity of California, San Francisco (UCSF)San FranciscoCAUSA
- Department of NeurologyUniversity of California, San FranciscoSan FranciscoCAUSA
| | - Xianhua Piao
- Weill Institute for NeuroscienceUniversity of California, San Francisco (UCSF)San FranciscoCAUSA
- Newborn Brain Research InstituteUniversity of California, San Francisco (UCSF)San FranciscoCAUSA
- Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell ResearchUniversity of California, San Francisco (UCSF)San FranciscoCAUSA
- Division of NeonatologyDepartment of PediatricsUniversity of California, San Francisco (UCSF)San FranciscoCAUSA
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10
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Wang Y, Goodman CL, Ringbauer J, Li Y, Stanley D. Prostaglandin A 2 induces apoptosis in three cell lines derived from the fall armyworm, Spodoptera frugiperda. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2021; 108:e21844. [PMID: 34519097 DOI: 10.1002/arch.21844] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Accepted: 08/31/2021] [Indexed: 06/13/2023]
Abstract
Animals maintain homeostasis of cell numbers, constantly creating new cells and eliminating others. Programmed cell death, apoptosis, is a mechanism of cell elimination and it acts in many aspects of animal biology. Drawing on the biomedical background, several signals launch the apoptosis mechanisms, including prostaglandins (PGs). Based on this information, we posed the hypothesis that PGs similarly induce apoptosis in insect cell lines. We used three Spodoptera frugiperda cell lines, including two newly established, BCIRL-SfNS-0518B-YL derived from the central nervous system and BCIRL-Sf4FB-0614-SGS derived from fat body, and the commercially available Sf9 cells. Using a kinetic apoptosis kit, we found treating SfNS cells for 18 h with 15 or 20 μM PGA2 led to decreases in cell numbers, coupled with increased numbers of apoptotic and dead cells. Similar exposures to 10 μM PGA2 (24 h) led to substantial increases in apoptotic cells, confirmed by a terminal deoxynucleotidyl transferase dUTP nick end labeling assay on a flow cytometer. The influence of PGA2 treatments increased with dosage, as we recorded about 20% apoptosis at 24 h post-PGA2 treatments (10 μM) and about 34% apoptosis at 24 h post-30 μM treatments. PGA2 treatments led to 10- to 30-fold increases in messenger RNAs (mRNAs) encoding apoptosis-specific caspases-1, -2, -3, and -5 at 12 h and 40- to 60-fold increases in mRNAs encoding caspases-1 and -2, 10-fold increases for caspases-3 and -5 at 24 h. These findings strongly support our hypothesis that PGs induce apoptosis in an insect cell line and confirm an additional PG action in insect biology.
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Affiliation(s)
- Yong Wang
- College of Bioscience and Biotechnology, Insect Resource Research Center for Engineering and Technology of Liaoning Province, Shenyang Agricultural University, Shenyang, China
| | - Cynthia L Goodman
- USDA/Agricultural Research Service, Biological Control of Insects Research Laboratory, Columbia, Missouri, USA
| | - Joseph Ringbauer
- USDA/Agricultural Research Service, Biological Control of Insects Research Laboratory, Columbia, Missouri, USA
| | - Yaofa Li
- Plant Protection Institute, Hebei Academy of Agricultural and Forestry Sciences, Baoding, China
| | - David Stanley
- USDA/Agricultural Research Service, Biological Control of Insects Research Laboratory, Columbia, Missouri, USA
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11
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Huang Y, Happonen KE, Burrola PG, O'Connor C, Hah N, Huang L, Nimmerjahn A, Lemke G. Microglia use TAM receptors to detect and engulf amyloid β plaques. Nat Immunol 2021; 22:586-594. [PMID: 33859405 PMCID: PMC8102389 DOI: 10.1038/s41590-021-00913-5] [Citation(s) in RCA: 201] [Impact Index Per Article: 67.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Accepted: 03/05/2021] [Indexed: 01/31/2023]
Abstract
Two microglial TAM receptor tyrosine kinases, Axl and Mer, have been linked to Alzheimer's disease, but their roles in disease have not been tested experimentally. We find that in Alzheimer's disease and its mouse models, induced expression of Axl and Mer in amyloid plaque-associated microglia was coupled to induced plaque decoration by the TAM ligand Gas6 and its co-ligand phosphatidylserine. In the APP/PS1 mouse model of Alzheimer's disease, genetic ablation of Axl and Mer resulted in microglia that were unable to normally detect, respond to, organize or phagocytose amyloid-β plaques. These major deficits notwithstanding, TAM-deficient APP/PS1 mice developed fewer dense-core plaques than APP/PS1 mice with normal microglia. Our findings reveal that the TAM system is an essential mediator of microglial recognition and engulfment of amyloid plaques and that TAM-driven microglial phagocytosis does not inhibit, but rather promotes, dense-core plaque development.
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Affiliation(s)
- Youtong Huang
- Molecular Neurobiology Laboratory, The Salk Institute for Biological Studies, La Jolla, CA, USA
- Division of Biological Sciences, University of California, San Diego, La Jolla, CA, USA
| | - Kaisa E Happonen
- Molecular Neurobiology Laboratory, The Salk Institute for Biological Studies, La Jolla, CA, USA
| | - Patrick G Burrola
- Molecular Neurobiology Laboratory, The Salk Institute for Biological Studies, La Jolla, CA, USA
| | - Carolyn O'Connor
- Flow Cytometry Core, The Salk Institute for Biological Studies, La Jolla, CA, USA
| | - Nasun Hah
- Chapman Foundations Genomic Sequencing Core, The Salk Institute for Biological Studies, La Jolla, CA, USA
| | - Ling Huang
- Razavi Newman Integrative Genomics and Bioinformatics Core, The Salk Institute for Biological Studies, La Jolla, CA, USA
| | - Axel Nimmerjahn
- Waitt Advanced Biophotonics Center, The Salk Institute for Biological Studies, La Jolla, CA, USA
| | - Greg Lemke
- Molecular Neurobiology Laboratory, The Salk Institute for Biological Studies, La Jolla, CA, USA.
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12
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Khan I, Yousif A, Chesnokov M, Hong L, Chefetz II. A decade of cell death studies: Breathing new life into necroptosis. Pharmacol Ther 2021; 220:107717. [DOI: 10.1016/j.pharmthera.2020.107717] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Accepted: 10/19/2020] [Indexed: 12/31/2022]
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13
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Liang X, Wang K, Du J, Tian J, Zhang H. The first visualization of chemotherapy-induced tumor apoptosis via magnetic particle imaging in a mouse model. Phys Med Biol 2020; 65:195004. [PMID: 32764190 DOI: 10.1088/1361-6560/abad7c] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Imaging technologies that allow non-radiative visualization and quantification of apoptosis have a great potential for assessing therapy response, early diagnosis, and disease monitoring. Magnetic particle imaging (MPI), the direct imaging of magnetic nanoparticles as positive contrast agent and sole signal source, enables high image contrast (no tissue background signal), potential high sensitivity, and quantifiable signal intensity. These properties confer a great potential for application to tumor apoptosis monitoring. In this study, a simple and robust method was used to conjugate Alexa Fluor 647-AnnexinV (AF647-Anx), which can avidly bind to apoptotic cells, to superparamagnetic iron oxide (SPIO) nanoparticles, termed AF647-Anx-SPIO, which serves as an MPI-detectable tracer. Based on this apoptosis-specific tracer, MPI can accurately and unambiguously detect and quantify apoptotic tumor cells. AF647-Anx-SPIO showed relatively high affinity for apoptotic cells, and differences in binding between treated (apoptotic rate 67.21% ± 1.36%) and untreated (apoptotic rate 10.12 ± 0.11%) cells could be detected by MPI in vitro (P < 0.05). Moreover, the imaging signal was almost proportional to the number of apoptotic cells determined using an MPI scanner (R 2 = 0.99). There was a greater accumulation of AF647-Anx-SPIO in tumors of drug-treated animals than in tumors of untreated animals (P < 0.05), and the difference could be detected by MPI ex vivo, while for in vivo imaging, no MPI imaging signal was detected in either group. Overall, this preliminary study demonstrates that MPI could be a potential imaging modality for tumor apoptosis imaging.
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Affiliation(s)
- Xin Liang
- Department of Radiology, First Clinical Medical College, Shanxi Medical University, Taiyuan, Shanxi Province, People's Republic of China. College of Medical Imaging, Shanxi Medical University, Taiyuan, Shanxi Province, People's Republic of China
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14
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Barth ND, Subiros-Funosas R, Mendive-Tapia L, Duffin R, Shields MA, Cartwright JA, Henriques ST, Sot J, Goñi FM, Lavilla R, Marwick JA, Vermeren S, Rossi AG, Egeblad M, Dransfield I, Vendrell M. A fluorogenic cyclic peptide for imaging and quantification of drug-induced apoptosis. Nat Commun 2020; 11:4027. [PMID: 32788676 PMCID: PMC7423924 DOI: 10.1038/s41467-020-17772-7] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Accepted: 07/17/2020] [Indexed: 02/06/2023] Open
Abstract
Programmed cell death or apoptosis is a central biological process that is dysregulated in many diseases, including inflammatory conditions and cancer. The detection and quantification of apoptotic cells in vivo is hampered by the need for fixatives or washing steps for non-fluorogenic reagents, and by the low levels of free calcium in diseased tissues that restrict the use of annexins. In this manuscript, we report the rational design of a highly stable fluorogenic peptide (termed Apo-15) that selectively stains apoptotic cells in vitro and in vivo in a calcium-independent manner and under wash-free conditions. Furthermore, using a combination of chemical and biophysical methods, we identify phosphatidylserine as a molecular target of Apo-15. We demonstrate that Apo-15 can be used for the quantification and imaging of drug-induced apoptosis in preclinical mouse models, thus creating opportunities for assessing the in vivo efficacy of anti-inflammatory and anti-cancer therapeutics. Programmed cell death or apoptosis is an essential biological process that is impaired in some diseases and can be used to assess the effectiveness of drugs. Here the authors design Apo-15 as a fluorogenic peptide for the detection and real-time imaging of apoptotic cells.
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Affiliation(s)
- Nicole D Barth
- Centre for Inflammation Research, University of Edinburgh, EH16 4TJ, Edinburgh, UK
| | | | - Lorena Mendive-Tapia
- Centre for Inflammation Research, University of Edinburgh, EH16 4TJ, Edinburgh, UK
| | - Rodger Duffin
- Centre for Inflammation Research, University of Edinburgh, EH16 4TJ, Edinburgh, UK
| | - Mario A Shields
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, 11724, USA
| | | | - Sónia Troeira Henriques
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, 4072, Australia.,School of Biomedical Sciences, Queensland University of Technology, Translational Research Institute, Brisbane, QLD, 4102, Australia
| | - Jesus Sot
- Instituto Biofisika (CSIC, UPV/EHU) and Departamento de Bioquímica, Universidad del País Vasco, Campus de Leioa, 48940, Leioa, Spain
| | - Felix M Goñi
- Instituto Biofisika (CSIC, UPV/EHU) and Departamento de Bioquímica, Universidad del País Vasco, Campus de Leioa, 48940, Leioa, Spain
| | - Rodolfo Lavilla
- Laboratory of Medicinal Chemistry and Institute of Biomedicine U. Barcelona (IBUB), Faculty of Pharmacy, University of Barcelona, 08028, Barcelona, Spain
| | - John A Marwick
- Centre for Inflammation Research, University of Edinburgh, EH16 4TJ, Edinburgh, UK
| | - Sonja Vermeren
- Centre for Inflammation Research, University of Edinburgh, EH16 4TJ, Edinburgh, UK
| | - Adriano G Rossi
- Centre for Inflammation Research, University of Edinburgh, EH16 4TJ, Edinburgh, UK
| | - Mikala Egeblad
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, 11724, USA
| | - Ian Dransfield
- Centre for Inflammation Research, University of Edinburgh, EH16 4TJ, Edinburgh, UK.
| | - Marc Vendrell
- Centre for Inflammation Research, University of Edinburgh, EH16 4TJ, Edinburgh, UK.
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15
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Zhang Y, Li H, Li X, Wu J, Xue T, Wu J, Shen H, Li X, Shen M, Chen G. TMEM16F Aggravates Neuronal Loss by Mediating Microglial Phagocytosis of Neurons in a Rat Experimental Cerebral Ischemia and Reperfusion Model. Front Immunol 2020; 11:1144. [PMID: 32733436 PMCID: PMC7359929 DOI: 10.3389/fimmu.2020.01144] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Accepted: 05/11/2020] [Indexed: 12/20/2022] Open
Abstract
Cerebral ischemia is a severe, acute condition, normally caused by cerebrovascular disease, and results in high rates of disability, and death. Phagoptosis is a newly recognized form of cell death caused by phagocytosis of viable cells, and has been reported to contribute to neuronal loss in brain tissue after ischemic stroke. Previous data indicated that exposure of phosphatidylserine to viable neurons could induce microglial phagocytosis of such neurons. Phosphatidylserine can be reversibly exposed to viable cells as a result of a calcium-activated phospholipid scramblase named TMEM16F. TMEM16F-mediated phospholipid scrambling on platelet membranes is critical for hemostasis and thrombosis, which plays an important role in Scott syndrome and has been confirmed by much research. However, few studies have investigated the association between TMEM16F and phagocytosis in ischemic stroke. In this study, a middle-cerebral-artery occlusion/reperfusion (MCAO/R) model was used in adult male Sprague-Dawley rats in vivo, and cultured neurons were exposed to oxygen-glucose deprivation/reoxygenation (OGD/R) to simulate cerebral ischemia-reperfusion (I/R) injury in vitro. We found that the protein level of TMEM16F was significantly increased at 12 h after I-R injury both in vivo and in vitro, and reversible phosphatidylserine exposure was confirmed in neurons undergoing I/R injury in vitro. Additionally, we constructed a LV-TMEM16F-RNAi transfection system to suppress the expression of TMEM16F during and after cerebral ischemia. As a result, TMEM16F knockdown alleviated motor function injury and decreased the microglial phagocytosis of viable neurons in the penumbra through inhibiting the “eat-me” signal phosphatidylserine. Our data indicate that reducing neuronal phosphatidylserine-exposure via deficiency of TMEM16F blocks phagocytosis of neurons and rescues stressed-but-still-viable neurons in the penumbra, which may contribute to reducing infarct volume and improving functional recovering.
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Affiliation(s)
- Yijie Zhang
- Brain and Nerve Research Laboratory, Department of Neurosurgery, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Haiying Li
- Brain and Nerve Research Laboratory, Department of Neurosurgery, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Xiang Li
- Brain and Nerve Research Laboratory, Department of Neurosurgery, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Jie Wu
- Brain and Nerve Research Laboratory, Department of Neurosurgery, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Tao Xue
- Brain and Nerve Research Laboratory, Department of Neurosurgery, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Jiang Wu
- Brain and Nerve Research Laboratory, Department of Neurosurgery, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Haitao Shen
- Brain and Nerve Research Laboratory, Department of Neurosurgery, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Xiang Li
- Brain and Nerve Research Laboratory, Department of Neurosurgery, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Meifen Shen
- Brain and Nerve Research Laboratory, Department of Neurosurgery, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Gang Chen
- Brain and Nerve Research Laboratory, Department of Neurosurgery, The First Affiliated Hospital of Soochow University, Suzhou, China
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16
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Abstract
Apoptosis is an important and necessary cell death program which promotes homeostasis and organismal survival. When dysregulated, however, it can lead to a myriad of pathologies from neurodegenerative diseases to cancer. Apoptosis is therefore the subject of intense study aimed at dissecting its pathways and molecular mechanisms. Although many assay methods exist for confirming whether an apoptotic response has occurred in vitro, most methods are destructive and involve laborious operator effort or specialized instrumentation. Here we describe a real-time, no-wash, microplate method which utilizes recombinant annexin V fusion proteins containing evolved binary subunits of NanoBiT™ luciferase. The fusion proteins, a time-released enzymatic substrate, a necrosis detection dye and exogenous calcium ions are delivered via an optimized and physiologically inert reagent directly to cells in culture at the time of treatment or dosing. Luminescent signals proportional to phosphatidylserine (PS) exposure and fluorescent signals generated as a result of loss of membrane integrity are then collected using a standard multimode plate reader at scheduled intervals over the exposure. The resulting luminescent and fluorescent data are then used to define the kinetics and magnitude of an apoptotic response. This study details our efforts to develop, characterize, and demonstrate the features of the assay by providing relevant examples from diverse cell models for programmed cell death.
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17
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Bae SY, Guan N, Yan R, Warner K, Taylor SD, Meyer AS. Measurement and models accounting for cell death capture hidden variation in compound response. Cell Death Dis 2020; 11:255. [PMID: 32312951 PMCID: PMC7171175 DOI: 10.1038/s41419-020-2462-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Revised: 04/06/2020] [Accepted: 04/07/2020] [Indexed: 11/09/2022]
Abstract
Cancer cell sensitivity or resistance is almost universally quantified through a direct or surrogate measure of cell number. However, compound responses can occur through many distinct phenotypic outcomes, including changes in cell growth, apoptosis, and non-apoptotic cell death. These outcomes have divergent effects on the tumor microenvironment, immune response, and resistance mechanisms. Here, we show that quantifying cell viability alone is insufficient to distinguish between these compound responses. Using an alternative assay and drug-response analysis amenable to high-throughput measurement, we find that compounds with identical viability outcomes can have very different effects on cell growth and death. Moreover, additive compound pairs with distinct growth/death effects can appear synergistic when only assessed by viability. Overall, these results demonstrate an approach to incorporating measurements of cell death when characterizing a pharmacologic response.
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Affiliation(s)
- Song Yi Bae
- Department of Pharmacology, University of Minnesota-Twin Cities, Minneapolis, MN, USA
| | - Ning Guan
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Rui Yan
- Institute for Computational and Mathematical Engineering, Stanford University, Stanford, CA, USA
| | - Katrina Warner
- Biological and Biomedical Sciences Program, Harvard University, Cambridge, MA, USA
| | - Scott D Taylor
- Department of Bioengineering, University of California, Los Angeles, CA, USA
| | - Aaron S Meyer
- Department of Bioengineering, University of California, Los Angeles, CA, USA.
- Department of Bioinformatics, University of California, Los Angeles, CA, USA.
- Jonsson Comprehensive Cancer Center, University of California, Los Angeles, CA, USA.
- Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, University of California, Los Angeles, CA, USA.
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18
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An X, Naowarojna N, Liu P, Reinhard BM. Hybrid Plasmonic Photoreactors as Visible Light-Mediated Bactericides. ACS APPLIED MATERIALS & INTERFACES 2020; 12:106-116. [PMID: 31800205 DOI: 10.1021/acsami.9b14834] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Photocatalytic compounds and complexes, such as tris(bipyridine)ruthenium(II), [Ru(bpy)3]2+, have recently attracted attention as light-mediated bactericides that can help to address the need for new antibacterial strategies. We demonstrate in this work that the bactericidal efficacy of [Ru(bpy)3]2+ and the control of its antibacterial function can be significantly enhanced through combination with a plasmonic nanoantenna. We report strong, visible light-controlled bacterial inactivation with a nanocomposite design that incorporates [Ru(bpy)3]2+ as a photocatalyst and a Ag nanoparticle (NP) core as a light-concentrating nanoantenna into a plasmonic hybrid photoreactor. The hybrid photoreactor platform is facilitated by a self-assembled lipid membrane that encapsulates the Ag NP and binds the photocatalyst. The lipid membrane renders the nanocomposite biocompatible in the absence of resonant illumination. Upon illumination, the plasmon-enhanced photoexcitation of the metal-to-ligand charge-transfer band of [Ru(bpy)3]2+ prepares the reactive excited state of the complex that oxidizes the nanocomposite membrane and increases its permeability. The photooxidation induces the release of [Ru(bpy)3]2+, Ag+, and peroxidized lipids into the ambient medium, where they interact synergistically to inactivate bacteria. We measured a 7 order of magnitude decrease in Gram-positive Arthrobacter sp. and a 4 order of magnitude decrease in Gram-negative Escherichia coli colony forming units with the photoreactor bactericides after visible light illumination for 1 h. In both cases, the photoreactor exceeds the bactericidal standard of a log reduction value of 3 and surpasses the antibacterial effect of free Ag NPs or [Ru(bpy)3]2+ by >4 orders of magnitude. We also implement the inactivation of a bacterial thin film in a proof-of-concept study.
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Affiliation(s)
- Xingda An
- Department of Chemistry , Boston University , Boston , Massachusetts 02215 , United States
- Photonics Center , Boston University , Boston , Massachusetts 02215 , United States
| | - Nathchar Naowarojna
- Department of Chemistry , Boston University , Boston , Massachusetts 02215 , United States
| | - Pinghua Liu
- Department of Chemistry , Boston University , Boston , Massachusetts 02215 , United States
| | - Björn M Reinhard
- Department of Chemistry , Boston University , Boston , Massachusetts 02215 , United States
- Photonics Center , Boston University , Boston , Massachusetts 02215 , United States
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19
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Shlomovitz I, Speir M, Gerlic M. Flipping the dogma - phosphatidylserine in non-apoptotic cell death. Cell Commun Signal 2019; 17:139. [PMID: 31665027 PMCID: PMC6819419 DOI: 10.1186/s12964-019-0437-0] [Citation(s) in RCA: 97] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Accepted: 09/10/2019] [Indexed: 12/18/2022] Open
Abstract
The exposure of phosphatidylserine (PS) on the outer plasma membrane has long been considered a unique feature of apoptotic cells. Together with other "eat me" signals, it enables the recognition and phagocytosis of dying cells (efferocytosis), helping to explain the immunologically-silent nature of apoptosis. Recently, however, PS exposure has also been reported in non-apoptotic forms of regulated inflammatory cell death, such as necroptosis, challenging previous dogma. In this review, we outline the evidence for PS exposure in non-apoptotic cells and extracellular vesicles (EVs), and discuss possible mechanisms based on our knowledge of apoptotic-PS exposure. In addition, we examine the outcomes of non-apoptotic PS exposure, including the reversibility of cell death, efferocytosis, and consequent inflammation. By examining PS biology, we challenge the established approach of distinguishing apoptosis from other cell death pathways by AnnexinV staining of PS externalization. Finally, we re-evaluate how PS exposure is thought to define apoptosis as an immunologically silent process distinct from other non-apoptotic and inflammatory cell death pathways. Ultimately, we suggest that a complete understanding of how regulated cell death processes affect the immune system is far from being fully elucidated.
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Affiliation(s)
- Inbar Shlomovitz
- Department of Clinical Microbiology and Immunology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Mary Speir
- Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical Research, Clayton, VIC 3168 Australia
- Department of Molecular and Translational Science, Monash University, Clayton, VIC 3800 Australia
| | - Motti Gerlic
- Department of Clinical Microbiology and Immunology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
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20
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Dias MC, Stuqui B, Provazzi PJS, Bittar C, Candido NM, de Matos RPA, Badial RM, do Bonfim CM, Melli PPDS, Quintana SM, Cordeiro JA, Rahal P, Calmon MDF. Analysis of Nucleotide Alterations in the E6 Genomic Region of Human Papillomavirus Types 6 and 11 in Condyloma Acuminatum Samples from Brazil. Adv Virol 2019; 2019:5697573. [PMID: 31186642 PMCID: PMC6521423 DOI: 10.1155/2019/5697573] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Revised: 02/27/2019] [Accepted: 03/17/2019] [Indexed: 11/17/2022] Open
Abstract
Condyloma acuminata (CA), or genital warts, are benign proliferative epidermal or mucous lesions that are caused by infection with human papillomavirus (HPV), mainly the low-risk types 6 and 11. HPV variants are defined as viral sequences that share identity in the nucleotide sequence of the L1 gene greater than 98%. Based on this criterion, HPV6 and 11 variant lineages have been studied, and there are ongoing attempts to correlate these genetic variants with different clinical findings of infection. Therefore, the aims of this study were to detect variants and nucleotide alterations present in the E6 regions of HPV types 6 and 11 found in CA samples, to correlate the HPV presence with the clinical-pathological data of the patients, and to determine phylogenetic relationships with variants from other places in the world. The E6 regions of 25 HPV6 samples and 7 HPV11 samples from CA were amplified using PCR with specific primers. The products were ligated to a cloning vector and five colonies of each sample were sequenced to observe the nucleotide alterations. Twelve samples were identified as the HPV6B3 variant, presenting the mutation (guanine) G474A (adenine), and one of them also showed the mutation (thymine) T369G. The other 13 patients were positive for HPV6B1 without nucleotide alterations. In the analysis of the HPV11 samples, all patients showed the mutations T137C and (cytosine) C380T. One patient also presented the nucleotide alteration T410C. None of the mutations found in the 32 analyzed samples resulted in amino acid changes. Patient age, local occurrence, and HIV infection did not show significant association with HPV infection. Besides, the data found in this study did not show a relationship with the geographical region of isolation when compared to other data from different regions of the world. In this way, despite the nucleotide alterations found, it was not possible to observe amino acid changes and variants grouping according to geographical region.
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Affiliation(s)
- Marina Carrara Dias
- Institute of Biosciences, Letters and Exact Sciences of São Paulo State University, São José do Rio Preto, SP, Brazil
| | - Bruna Stuqui
- Institute of Biosciences, Letters and Exact Sciences of São Paulo State University, São José do Rio Preto, SP, Brazil
| | - Paola Jocelan Scarin Provazzi
- Institute of Biosciences, Letters and Exact Sciences of São Paulo State University, São José do Rio Preto, SP, Brazil
| | - Cíntia Bittar
- Institute of Biosciences, Letters and Exact Sciences of São Paulo State University, São José do Rio Preto, SP, Brazil
| | - Natália Maria Candido
- Institute of Biosciences, Letters and Exact Sciences of São Paulo State University, São José do Rio Preto, SP, Brazil
| | - Renata Prandini Adum de Matos
- Institute of Biosciences, Letters and Exact Sciences of São Paulo State University, São José do Rio Preto, SP, Brazil
| | - Rodolfo Miglioli Badial
- Institute of Biosciences, Letters and Exact Sciences of São Paulo State University, São José do Rio Preto, SP, Brazil
| | - Caroline Measso do Bonfim
- Institute of Biosciences, Letters and Exact Sciences of São Paulo State University, São José do Rio Preto, SP, Brazil
| | | | | | | | - Paula Rahal
- Institute of Biosciences, Letters and Exact Sciences of São Paulo State University, São José do Rio Preto, SP, Brazil
| | - Marilia de Freitas Calmon
- Institute of Biosciences, Letters and Exact Sciences of São Paulo State University, São José do Rio Preto, SP, Brazil
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21
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Mazzoni F, Müller C, DeAssis J, Lew D, Leevy WM, Finnemann SC. Non-invasive in vivo fluorescence imaging of apoptotic retinal photoreceptors. Sci Rep 2019; 9:1590. [PMID: 30733587 PMCID: PMC6367443 DOI: 10.1038/s41598-018-38363-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Accepted: 12/27/2018] [Indexed: 12/05/2022] Open
Abstract
Phosphatidylserine externalization is an early molecular signature for apoptosis. In many retinal degenerative diseases, photoreceptor neurons die by apoptosis. Here, we report utility of the phosphatidylserine-binding conjugate of Bis(zinc(II)-dipicolylamine (Zn-DPA) with Texas-red (PSVue-550) in transiently labeling apoptotic photoreceptors in living pigmented or albino rats and mice with retinal degeneration. Applying PSVue-550 as eyedrop is non-toxic and eliminates need for intraocular injection. PSVue-550 fluorescence specifically and transiently labeling dying retinal photoreceptors is detectable in anesthetized animals using standard retinal or whole small animal imaging systems. Importantly, prior PSVue-550 eyedrop administration and imaging does not affect repeat testing. Altogether, our results establish PSVue-550 imaging as a completely non-invasive method that provides the opportunity to longitudinally monitor retinal photoreceptor cell death in preclinical studies.
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Affiliation(s)
- Francesca Mazzoni
- Department of Biological Sciences, Center for Cancer, Genetic Diseases and Gene Regulation, Fordham University, Bronx, NY, 10458, USA
| | - Claudia Müller
- Department of Biological Sciences, Center for Cancer, Genetic Diseases and Gene Regulation, Fordham University, Bronx, NY, 10458, USA
| | - Jonathan DeAssis
- Department of Biological Sciences, Center for Cancer, Genetic Diseases and Gene Regulation, Fordham University, Bronx, NY, 10458, USA
| | - Deborah Lew
- Department of Biological Sciences, Center for Cancer, Genetic Diseases and Gene Regulation, Fordham University, Bronx, NY, 10458, USA
| | - W Matthew Leevy
- Department of Biological Sciences, 100 Galvin Life Science Center, University of Notre Dame, Notre Dame, IN, 46556, USA
| | - Silvia C Finnemann
- Department of Biological Sciences, Center for Cancer, Genetic Diseases and Gene Regulation, Fordham University, Bronx, NY, 10458, USA.
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22
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Murschhauser A, Röttgermann PJF, Woschée D, Ober MF, Yan Y, Dawson KA, Rädler JO. A high-throughput microscopy method for single-cell analysis of event-time correlations in nanoparticle-induced cell death. Commun Biol 2019; 2:35. [PMID: 30701200 PMCID: PMC6345847 DOI: 10.1038/s42003-019-0282-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Accepted: 12/27/2018] [Indexed: 12/20/2022] Open
Abstract
The temporal context of cell death decisions remains generally hidden in ensemble measurements with endpoint readouts. Here, we describe a method to extract event times from fluorescence time traces of cell death-related markers in automated live-cell imaging on single-cell arrays (LISCA) using epithelial A549 lung and Huh7 liver cancer cells as a model system. In pairwise marker combinations, we assess the chronological sequence and delay times of the events lysosomal membrane permeabilization, mitochondrial outer membrane permeabilization and oxidative burst after exposure to 58 nm amino-functionalized polystyrene nanoparticles (PS-NH2 nanoparticles). From two-dimensional event-time scatter plots we infer a lysosomal signal pathway at a low dose of nanoparticles (25 µg mL-1) for both cell lines, while at a higher dose (100 µg mL-1) a mitochondrial pathway coexists in A549 cells, but not in Huh7. In general, event-time correlations provide detailed insights into heterogeneity and interdependencies in signal transmission pathways.
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Affiliation(s)
- Alexandra Murschhauser
- Faculty of Physics and Center for NanoSciene (CeNS), Ludwig-Maximilians-Universität, Geschwister-Scholl-Platz 1, Munich, 80539 Germany
| | - Peter J. F. Röttgermann
- Faculty of Physics and Center for NanoSciene (CeNS), Ludwig-Maximilians-Universität, Geschwister-Scholl-Platz 1, Munich, 80539 Germany
| | - Daniel Woschée
- Faculty of Physics and Center for NanoSciene (CeNS), Ludwig-Maximilians-Universität, Geschwister-Scholl-Platz 1, Munich, 80539 Germany
| | - Martina F. Ober
- Faculty of Physics and Center for NanoSciene (CeNS), Ludwig-Maximilians-Universität, Geschwister-Scholl-Platz 1, Munich, 80539 Germany
| | - Yan Yan
- Centre for BioNano Interactions, School of Chemistry and Chemical Biology, University College Dublin, Belfield, Dublin 4, Ireland
| | - Kenneth A. Dawson
- Centre for BioNano Interactions, School of Chemistry and Chemical Biology, University College Dublin, Belfield, Dublin 4, Ireland
| | - Joachim O. Rädler
- Faculty of Physics and Center for NanoSciene (CeNS), Ludwig-Maximilians-Universität, Geschwister-Scholl-Platz 1, Munich, 80539 Germany
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23
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Su D, Hu X, Dong C, Ren J. Determination of Caspase-3 Activity and Its Inhibition Constant by Combination of Fluorescence Correlation Spectroscopy with a Microwell Chip. Anal Chem 2017; 89:9788-9796. [DOI: 10.1021/acs.analchem.7b01735] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Di Su
- School of Chemistry & Chemical Engineering, State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, P. R. China
| | - Xiaocai Hu
- School of Chemistry & Chemical Engineering, State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, P. R. China
| | - Chaoqing Dong
- School of Chemistry & Chemical Engineering, State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, P. R. China
| | - Jicun Ren
- School of Chemistry & Chemical Engineering, State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, P. R. China
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24
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Lemke G. Phosphatidylserine Is the Signal for TAM Receptors and Their Ligands. Trends Biochem Sci 2017; 42:738-748. [PMID: 28734578 DOI: 10.1016/j.tibs.2017.06.004] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2017] [Revised: 06/04/2017] [Accepted: 06/08/2017] [Indexed: 12/20/2022]
Abstract
Nature repeatedly repurposes, in that molecules that serve as metabolites, energy depots, or polymer subunits are at the same time used to deliver signals within and between cells. The preeminent example of this repurposing is ATP, which functions as a building block for nucleic acids, an energy source for enzymatic reactions, a phosphate donor to regulate intracellular signaling, and a neurotransmitter to control the activity of neurons. A series of recent studies now consolidates the view that phosphatidylserine (PtdSer), a common phospholipid constituent of membrane bilayers, is similarly repurposed for use as a signal between cells and that the ligands and receptors of the Tyro3/Axl/Mer (TAM) family of receptor tyrosine kinases (RTKs) are prominent transducers of this signal.
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Affiliation(s)
- Greg Lemke
- Molecular Neurobiology Laboratory, Salk Institute for Biological Studies, La Jolla, CA 92037, USA; Immunobiology and Microbial Pathogenesis Laboratory, Salk Institute for Biological Studies, La Jolla, CA 92037, USA.
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Zargarian S, Shlomovitz I, Erlich Z, Hourizadeh A, Ofir-Birin Y, Croker BA, Regev-Rudzki N, Edry-Botzer L, Gerlic M. Phosphatidylserine externalization, "necroptotic bodies" release, and phagocytosis during necroptosis. PLoS Biol 2017. [PMID: 28650960 PMCID: PMC5501695 DOI: 10.1371/journal.pbio.2002711] [Citation(s) in RCA: 134] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Necroptosis is a regulated, nonapoptotic form of cell death initiated by receptor-interacting protein kinase-3 (RIPK3) and mixed lineage kinase domain-like (MLKL) proteins. It is considered to be a form of regulated necrosis, and, by lacking the “find me” and “eat me” signals that are a feature of apoptosis, necroptosis is considered to be inflammatory. One such “eat me” signal observed during apoptosis is the exposure of phosphatidylserine (PS) on the outer plasma membrane. Here, we demonstrate that necroptotic cells also expose PS after phosphorylated mixed lineage kinase-like (pMLKL) translocation to the membrane. Necroptotic cells that expose PS release extracellular vesicles containing proteins and pMLKL to their surroundings. Furthermore, inhibition of pMLKL after PS exposure can reverse the process of necroptosis and restore cell viability. Finally, externalization of PS by necroptotic cells drives recognition and phagocytosis, and this may limit the inflammatory response to this nonapoptotic form of cell death. The exposure of PS to the outer membrane and to extracellular vesicles is therefore a feature of necroptotic cell death and may serve to provide an immunologically-silent window by generating specific “find me” and “eat me” signals. Necroptosis, a recently discovered regulated form of cell death, is widely considered to be inflammatory due to the absence of specific “find me” and “eat me” signals prior to lytic death. Here, we demonstrate that necroptotic cells generate “find me” and “eat me” signals by exposure of phosphatidylserine on their outer plasma membrane. This was further associated with the release of extracellular vesicles (“necroptotic bodies”) that contain phosphatidylserine, pMLKL (a key necroptotic marker), as well as other proteins. These signals drive recognition and phagocytosis of necroptotic cells to modulate the immune response. The exposure of phosphatidylserine and release of “necroptotic bodies” indicate that apoptosis and necroptosis share some common biochemical and cellular features and highlight the need for new biomarkers to distinguish apoptotic and necroptotic cell death.
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Affiliation(s)
- Sefi Zargarian
- Department of Clinical Microbiology and Immunology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Inbar Shlomovitz
- Department of Clinical Microbiology and Immunology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Ziv Erlich
- Department of Clinical Microbiology and Immunology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Aria Hourizadeh
- Department of Clinical Microbiology and Immunology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Yifat Ofir-Birin
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Ben A. Croker
- Division of Hematology/Oncology, Boston Children’s Hospital, Boston, Massachusetts, United States of America
- Department of Pediatrics, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Neta Regev-Rudzki
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Liat Edry-Botzer
- Department of Clinical Microbiology and Immunology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Motti Gerlic
- Department of Clinical Microbiology and Immunology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
- * E-mail:
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Axonal Degeneration in Retinal Ganglion Cells Is Associated with a Membrane Polarity-Sensitive Redox Process. J Neurosci 2017; 37:3824-3839. [PMID: 28275163 DOI: 10.1523/jneurosci.3882-16.2017] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Revised: 02/15/2017] [Accepted: 02/28/2017] [Indexed: 12/13/2022] Open
Abstract
Axonal degeneration is a pathophysiological mechanism common to several neurodegenerative diseases. The slow Wallerian degeneration (WldS) mutation, which results in reduced axonal degeneration in the central and peripheral nervous systems, has provided insight into a redox-dependent mechanism by which axons undergo self-destruction. We studied early molecular events in axonal degeneration with single-axon laser axotomy and time-lapse imaging, monitoring the initial changes in transected axons of purified retinal ganglion cells (RGCs) from wild-type and WldS rat retinas using a polarity-sensitive annexin-based biosensor (annexin B12-Cys101,Cys260-N,N'-dimethyl-N-(iodoacetyl)-N'-(7-nitrobenz-2-oxa-1,3-diazol-4-yl) ethylenediamine). Transected axons demonstrated a rapid and progressive change in membrane phospholipid polarity, manifested as phosphatidylserine externalization, which was significantly delayed and propagated more slowly in axotomized WldS RGCs compared with wild-type axons. Delivery of bis(3-propionic acid methyl ester)phenylphosphine borane complex, a cell-permeable intracellular disulfide-reducing drug, slowed the onset and velocity of phosphatidylserine externalization in wild-type axons significantly, replicating the WldS phenotype, whereas extracellular redox modulation reversed the WldS phenotype. These findings are consistent with an intra-axonal redox mechanism for axonal degeneration associated with the initiation and propagation of phosphatidylserine externalization after axotomy.SIGNIFICANCE STATEMENT Axonal degeneration is a neuronal process independent of somal apoptosis, the propagation of which is unclear. We combined single-cell laser axotomy with time-lapse imaging to study the dynamics of phosphatidylserine externalization immediately after axonal injury in purified retinal ganglion cells. The extension of phosphatidylserine externalization was slowed and delayed in Wallerian degeneration slow (WldS) axons and this phenotype could be reproduced by intra-axonal disulfide reduction in wild-type axons and reversed by extra-axonal reduction in WldS axons. These results are consistent with a redox mechanism for propagation of membrane polarity asymmetry in axonal degeneration.
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Sommer A, Kordowski F, Büch J, Maretzky T, Evers A, Andrä J, Düsterhöft S, Michalek M, Lorenzen I, Somasundaram P, Tholey A, Sönnichsen FD, Kunzelmann K, Heinbockel L, Nehls C, Gutsmann T, Grötzinger J, Bhakdi S, Reiss K. Phosphatidylserine exposure is required for ADAM17 sheddase function. Nat Commun 2016; 7:11523. [PMID: 27161080 PMCID: PMC4866515 DOI: 10.1038/ncomms11523] [Citation(s) in RCA: 122] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Accepted: 04/05/2016] [Indexed: 02/07/2023] Open
Abstract
ADAM17, a prominent member of the 'Disintegrin and Metalloproteinase' (ADAM) family, controls vital cellular functions through cleavage of transmembrane substrates. Here we present evidence that surface exposure of phosphatidylserine (PS) is pivotal for ADAM17 to exert sheddase activity. PS exposure is tightly coupled to substrate shedding provoked by diverse ADAM17 activators. PS dependency is demonstrated in the following: (a) in Raji cells undergoing apoptosis; (b) in mutant PSA-3 cells with manipulatable PS content; and (c) in Scott syndrome lymphocytes genetically defunct in their capacity to externalize PS in response to intracellular Ca(2+) elevation. Soluble phosphorylserine but not phosphorylcholine inhibits substrate cleavage. The isolated membrane proximal domain (MPD) of ADAM17 binds to PS but not to phosphatidylcholine liposomes. A cationic PS-binding motif is identified in this domain, replacement of which abrogates liposome-binding and renders the protease incapable of cleaving its substrates in cells. We speculate that surface-exposed PS directs the protease to its targets where it then executes its shedding function.
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Affiliation(s)
- Anselm Sommer
- Department of Dermatology, University of Kiel, Schittenhelmstrasse 7, Kiel 24105, Germany
| | - Felix Kordowski
- Department of Dermatology, University of Kiel, Schittenhelmstrasse 7, Kiel 24105, Germany
| | - Joscha Büch
- Department of Dermatology, University of Kiel, Schittenhelmstrasse 7, Kiel 24105, Germany
| | - Thorsten Maretzky
- Arthritis and Tissue Degeneration Program, Hospital for Special Surgery at Weill Medical College of Cornell University, New York, New York 10021, USA
| | - Astrid Evers
- Arthritis and Tissue Degeneration Program, Hospital for Special Surgery at Weill Medical College of Cornell University, New York, New York 10021, USA
| | - Jörg Andrä
- Hamburg University of Applied Science, Ulmenliet 20, Hamburg 21033, Germany
| | - Stefan Düsterhöft
- Institute of Biochemistry, University of Kiel, Olshausenstrasse 40, Kiel 24098, Germany
| | - Matthias Michalek
- Institute of Biochemistry, University of Kiel, Olshausenstrasse 40, Kiel 24098, Germany
| | - Inken Lorenzen
- Institute of Biochemistry, University of Kiel, Olshausenstrasse 40, Kiel 24098, Germany
| | - Prasath Somasundaram
- Division of Systematic Proteome Research and Bioanalytics, Institute for Experimental Medicine, University of Kiel, Kiel 24105, Germany
| | - Andreas Tholey
- Division of Systematic Proteome Research and Bioanalytics, Institute for Experimental Medicine, University of Kiel, Kiel 24105, Germany
| | - Frank D Sönnichsen
- Otto Diels Institute for Organic Chemistry, University of Kiel, Kiel 24118, Germany
| | - Karl Kunzelmann
- Physiological Institute, University of Regensburg, Universitätsstrasse 31, Regensburg 93053, Germany
| | - Lena Heinbockel
- Forschungszentrum Borstel, Leibniz-Zentrum für Medizin and Biowissenschaften, Borstel 23845, Germany
| | - Christian Nehls
- Forschungszentrum Borstel, Leibniz-Zentrum für Medizin and Biowissenschaften, Borstel 23845, Germany
| | - Thomas Gutsmann
- Forschungszentrum Borstel, Leibniz-Zentrum für Medizin and Biowissenschaften, Borstel 23845, Germany
| | - Joachim Grötzinger
- Institute of Biochemistry, University of Kiel, Olshausenstrasse 40, Kiel 24098, Germany
| | - Sucharit Bhakdi
- Department of Dermatology, University of Kiel, Schittenhelmstrasse 7, Kiel 24105, Germany
| | - Karina Reiss
- Department of Dermatology, University of Kiel, Schittenhelmstrasse 7, Kiel 24105, Germany
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28
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Röttgermann PJF, Dawson KA, Rädler JO. Time-Resolved Study of Nanoparticle Induced Apoptosis Using Microfabricated Single Cell Arrays. ACTA ACUST UNITED AC 2016; 5:microarrays5020008. [PMID: 27600074 PMCID: PMC5003484 DOI: 10.3390/microarrays5020008] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Revised: 04/01/2016] [Accepted: 04/07/2016] [Indexed: 02/06/2023]
Abstract
Cell fate decisions like apoptosis are heterogeneously implemented within a cell population and, consequently, the population response is recognized as sum of many individual dynamic events. Here, we report on the use of micro-patterned single-cell arrays for real-time tracking of nanoparticle-induced (NP) cell death in sets of thousands of cells in parallel. Annexin (pSIVA) and propidium iodide (PI), two fluorescent indicators of apoptosis, are simultaneously monitored after exposure to functionalized polystyrene (PS - NH 2) nanobeads as a model system. We find that the distribution of Annexin onset times shifts to later times and broadens as a function of decreasing NP dose. We discuss the mean time-to-death as a function of dose, and show how the EC 50 value depends both on dose and time of measurement. In addition, the correlations between the early and late apoptotic markers indicate a systematic shift from apoptotic towards necrotic cell death during the course of the experiment. Thus, our work demonstrates the potential of array-based single cell cytometry for kinetic analysis of signaling cascades in a high-throughput format.
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Affiliation(s)
- Peter J F Röttgermann
- Faculty of Physics and Center for NanoSciene (CeNS), Ludwig-Maximilians-Universität, Geschwister-Scholl-Platz 1, 80539 Munich, Germany.
| | - Kenneth A Dawson
- Centre for BioNano Interactions, School of Chemistry and Chemical Biology, University College Dublin, Belfield, Dublin 4, Ireland.
| | - Joachim O Rädler
- Faculty of Physics and Center for NanoSciene (CeNS), Ludwig-Maximilians-Universität, Geschwister-Scholl-Platz 1, 80539 Munich, Germany.
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29
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Calì B, Ceolin S, Ceriani F, Bortolozzi M, Agnellini AHR, Zorzi V, Predonzani A, Bronte V, Molon B, Mammano F. Critical role of gap junction communication, calcium and nitric oxide signaling in bystander responses to focal photodynamic injury. Oncotarget 2016; 6:10161-74. [PMID: 25868859 PMCID: PMC4496347 DOI: 10.18632/oncotarget.3553] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2015] [Accepted: 02/14/2015] [Indexed: 12/02/2022] Open
Abstract
Ionizing and nonionizing radiation affect not only directly targeted cells but also surrounding “bystander” cells. The underlying mechanisms and therapeutic role of bystander responses remain incompletely defined. Here we show that photosentizer activation in a single cell triggers apoptosis in bystander cancer cells, which are electrically coupled by gap junction channels and support the propagation of a Ca2+ wave initiated in the irradiated cell. The latter also acts as source of nitric oxide (NO) that diffuses to bystander cells, in which NO levels are further increased by a mechanism compatible with Ca2+-dependent enzymatic production. We detected similar signals in tumors grown in dorsal skinfold chambers applied to live mice. Pharmacological blockade of connexin channels significantly reduced the extent of apoptosis in bystander cells, consistent with a critical role played by intercellular communication, Ca2+ and NO in the bystander effects triggered by photodynamic therapy.
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Affiliation(s)
- Bianca Calì
- Foundation for Advanced Biomedical Research, Venetian Institute of Molecular Medicine, Padua, Italy.,University of Padua, Department of Surgery Oncology and Gastroenterology, Oncology and Immunology Section, Padua, Italy
| | - Stefano Ceolin
- University of Padua, Department of Physics and Astronomy, Padua, Italy
| | - Federico Ceriani
- Foundation for Advanced Biomedical Research, Venetian Institute of Molecular Medicine, Padua, Italy.,University of Padua, Department of Physics and Astronomy, Padua, Italy
| | - Mario Bortolozzi
- Foundation for Advanced Biomedical Research, Venetian Institute of Molecular Medicine, Padua, Italy.,University of Padua, Department of Physics and Astronomy, Padua, Italy
| | - Andrielly H R Agnellini
- Foundation for Advanced Biomedical Research, Venetian Institute of Molecular Medicine, Padua, Italy.,University of Padua, Department of Surgery Oncology and Gastroenterology, Oncology and Immunology Section, Padua, Italy
| | - Veronica Zorzi
- Foundation for Advanced Biomedical Research, Venetian Institute of Molecular Medicine, Padua, Italy.,University of Padua, Department of Physics and Astronomy, Padua, Italy
| | | | - Vincenzo Bronte
- Foundation for Advanced Biomedical Research, Venetian Institute of Molecular Medicine, Padua, Italy.,Verona University Hospital, Department of Pathology and Diagnostics, Immunology Section, Verona, Italy
| | | | - Fabio Mammano
- Foundation for Advanced Biomedical Research, Venetian Institute of Molecular Medicine, Padua, Italy.,University of Padua, Department of Physics and Astronomy, Padua, Italy.,Present address: CNR, Institute of Cell Biology and Neurobiology, Monterotondo (RM), Italy
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30
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von Büdingen HC, Mei F, Greenfield A, Jahn S, Shen YAA, Reid HH, McKemy DD, Chan JR. The myelin oligodendrocyte glycoprotein directly binds nerve growth factor to modulate central axon circuitry. J Cell Biol 2015; 210:891-8. [PMID: 26347141 PMCID: PMC4576870 DOI: 10.1083/jcb.201504106] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
Myelin oligodendrocyte glycoprotein, expressed on the outermost lamellae of the
myelin sheath, is a novel and specific binding partner for NGF that may modulate
local concentrations of the neurotrophin in the spinal cord microenvironment. Myelin oligodendrocyte glycoprotein (MOG) is a central nervous system myelin-specific
molecule expressed on the outer lamellae of myelin. To date, the exact function of
MOG has remained unknown, with MOG knockout mice displaying normal myelin
ultrastructure and no apparent specific phenotype. In this paper, we identify nerve
growth factor (NGF) as a binding partner for MOG and demonstrate that this
interaction is capable of sequestering NGF from TrkA-expressing neurons to modulate
axon growth and survival. Deletion of MOG results in aberrant sprouting of
nociceptive neurons in the spinal cord. Binding of NGF to MOG may offer widespread
implications into mechanisms that underlie pain pathways.
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31
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Zeng W, Wang X, Xu P, Liu G, Eden HS, Chen X. Molecular imaging of apoptosis: from micro to macro. Theranostics 2015; 5:559-82. [PMID: 25825597 PMCID: PMC4377726 DOI: 10.7150/thno.11548] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Accepted: 02/18/2015] [Indexed: 12/21/2022] Open
Abstract
Apoptosis, or programmed cell death, is involved in numerous human conditions including neurodegenerative diseases, ischemic damage, autoimmune disorders and many types of cancer, and is often confused with other types of cell death. Therefore strategies that enable visualized detection of apoptosis would be of enormous benefit in the clinic for diagnosis, patient management, and development of new therapies. In recent years, improved understanding of the apoptotic machinery and progress in imaging modalities have provided opportunities for researchers to formulate microscopic and macroscopic imaging strategies based on well-defined molecular markers and/or physiological features. Correspondingly, a large collection of apoptosis imaging probes and approaches have been documented in preclinical and clinical studies. In this review, we mainly discuss microscopic imaging assays and macroscopic imaging probes, ranging in complexity from simple attachments of reporter moieties to proteins that interact with apoptotic biomarkers, to rationally designed probes that target biochemical changes. Their clinical translation will also be our focus.
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32
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Pradhan N, Pratheek B, Garai A, Kumar A, Meena VS, Ghosh S, Singh S, Kumari S, Chandrashekar T, Goswami C, Chattopadhyay S, Kar S, Maiti PK. Induction of apoptosis by Fe(salen)Cl through caspase-dependent pathway specifically in tumor cells. Cell Biol Int 2014; 38:1118-31. [DOI: 10.1002/cbin.10308] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2013] [Accepted: 04/14/2014] [Indexed: 12/21/2022]
Affiliation(s)
| | - B.M. Pratheek
- School of Biological Sciences; National Institute of Science Education & Research; Bhubaneswar India
| | - Antara Garai
- School of Chemical Sciences; National Institute of Science Education & Research; Bhubaneswar India
| | - Ashutosh Kumar
- School of Biological Sciences; National Institute of Science Education & Research; Bhubaneswar India
| | - Vikram S. Meena
- School of Biological Sciences; National Institute of Science Education & Research; Bhubaneswar India
| | - Shyamasree Ghosh
- School of Biological Sciences; National Institute of Science Education & Research; Bhubaneswar India
| | | | - Shikha Kumari
- School of Biological Sciences; National Institute of Science Education & Research; Bhubaneswar India
| | - T.K. Chandrashekar
- School of Chemical Sciences; National Institute of Science Education & Research; Bhubaneswar India
| | - Chandan Goswami
- School of Biological Sciences; National Institute of Science Education & Research; Bhubaneswar India
| | - Subhasis Chattopadhyay
- School of Biological Sciences; National Institute of Science Education & Research; Bhubaneswar India
| | - Sanjib Kar
- School of Chemical Sciences; National Institute of Science Education & Research; Bhubaneswar India
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Ruggiero L, Finnemann SC. Lack of effect of microfilament or microtubule cytoskeleton-disrupting agents on restriction of externalized phosphatidylserine to rod photoreceptor outer segment tips. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2014; 801:91-6. [PMID: 24664685 PMCID: PMC6788739 DOI: 10.1007/978-1-4614-3209-8_12] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
In the mammalian retina, life-long renewal of rod photoreceptor outer segments involves circadian shedding of distal outer segment tips and their prompt phagocytosis by the adjacent retinal pigment epithelium (RPE) every morning after light onset. Failure of this process causes retinal dystrophy in animal models and its decline likely contributes to retinal aging and some forms of degeneration of the human retina. We previously found that surface exposure of the membrane phospholipid phosphatidylserine (PS) is restricted to outer segment tips with discrete boundaries in mouse retina and that both frequency and length of tips exposing PS peak after light onset. Here, we sought to test mechanisms photoreceptors use to restrict PS specifically to their outer segment tips. To this end, we tested whether nocodazole or cytochalasin D, perturbing microtubule or F-actin microfilament cytoskeleton, respectively, affect localization of externalized PS at outer segment tips. Fluorescence imaging of PS exposed by rods in freshly dissected, live mouse retina showed normal PS demarcation of outer segment tips regardless of drug treatment. These results suggest that the mechanism that restricts externalized PS to rod tips is independent of F-actin and microtubule cytoskeletal systems.
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Affiliation(s)
- Linda Ruggiero
- Department of Biological Sciences, Center for Cancer, Genetic Diseases, and Gene Regulation, Fordham University, 441 East Fordham Road, Larkin Hall, 10458, Bronx, NY, USA,
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34
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Halama A, Riesen N, Möller G, Hrabě de Angelis M, Adamski J. Identification of biomarkers for apoptosis in cancer cell lines using metabolomics: tools for individualized medicine. J Intern Med 2013; 274:425-39. [PMID: 24127940 DOI: 10.1111/joim.12117] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND Metabolomics is a versatile unbiased method to search for biomarkers of human disease. In particular, one approach in cancer therapy is to promote apoptosis in tumour cells; this could be improved with specific biomarkers of apoptosis for monitoring treatment. We recently observed specific metabolic patterns in apoptotic cell lines; however, in that study, apoptosis was only induced with one pro-apoptotic agent, staurosporine. OBJECTIVE The aim of this study was to find novel biomarkers of apoptosis by verifying our previous findings using two further pro-apoptotic agents, 5-fluorouracil and etoposide, that are commonly used in anticancer treatment. METHODS Metabolic parameters were assessed in HepG2 and HEK293 cells using the newborn screening assay adapted for cell culture approaches, quantifying the levels of amino acids and acylcarnitines with mass spectrometry. RESULTS We were able to identify apoptosis-specific changes in the metabolite profile. Moreover, the amino acids alanine and glutamate were both significantly up-regulated in apoptotic HepG2 and HEK293 cells irrespective of the apoptosis inducer. CONCLUSION Our observations clearly indicate the potential of metabolomics in detecting metabolic biomarkers applicable in theranostics and for monitoring drug efficacy.
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Affiliation(s)
- A Halama
- Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Experimental Genetics, Genome Analysis Center, Neuherberg, Germany
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35
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Liu R, Lin G, Xu H. An efficient method for dorsal root ganglia neurons purification with a one-time anti-mitotic reagent treatment. PLoS One 2013; 8:e60558. [PMID: 23565257 PMCID: PMC3614500 DOI: 10.1371/journal.pone.0060558] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2012] [Accepted: 02/27/2013] [Indexed: 11/18/2022] Open
Abstract
Background The dorsal root ganglia (DRG) neuron is an invaluable tool in axon growth, growth factor regulation, myelin formation and myelin-relevant researches. The purification of DRG neurons is a key step in these studies. Traditionally, purified DRG neurons were obtained in two weeks after exposure to several rounds of anti-mitotic reagent. Methods and Results In this report, a novel, simple and efficient method for DRG purification is presented. DRG cultures were treated once with a high-dose anti-mitotic reagent cocktail for 72 hours. Using this new method, DRG neurons were obtained with 99% purification within 1 week. We confirmed that the neurite growth and the viability of the purified DRG neurons have no difference from the DRG neurons purified by traditional method. Furthermore, P0 and MBP expression was observed in myelin by immunocytochemistry in the DRG/SC co-culture system. The formation of mature node of Ranvier in DRG-Schwann cell co-culture system was observed using anti-Nav 1.6 and anti-caspr antibody. Conclusion and Significance The results indicate that this high dose single treatment did not compromise the capacity of DRG neurons for myelin formation in the DRG/SC co-culture system. In conclusion, a convenient approach for purifying DRG neurons was developed which is time-saving and high-efficiency.
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Affiliation(s)
- Rui Liu
- The Geriatric Department, Tangdu Hospital, The Fourth Military Medical University, Xi'an, Shaanxi Province, PR China
- * E-mail: (HX); (RL)
| | - Gou Lin
- LONI, Department of Neurology, University of California Los Angeles, Los Angeles, California, United States of America
| | - Hanpeng Xu
- The Basic Medical School, The Fourth Military Medical University, Xi'an, Shaanxi Province, PR China
- * E-mail: (HX); (RL)
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36
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Ruan L, Xu Z, Lan T, Wang J, Liu H, Li C, Dong C, Ren J. Highly sensitive method for assay of drug-induced apoptosis using fluorescence correlation spectroscopy. Anal Chem 2012; 84:7350-8. [PMID: 22876965 DOI: 10.1021/ac301654g] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Apoptosis plays a crucial role in many biological processes and pathogenesis of various malignancies and diseases of the immune system. In this paper, we described a novel method for sensitive detection of drug-induced apoptosis by using fluorescence correlation spectroscopy (FCS). The principle of this method is based on the assay of DNA fragmentation in the process of the drug-induced apoptosis. FCS is a single molecule method, and it can be used for sensitive and selective assay of DNA fragmentation without separation. We first developed a highly sensitive method for characterization of DNA fragments using a home-built FCS system and SYBR Green I as fluorescent DNA-intercalating dye, and then established a model of drug-induced apoptosis using human pancreatic cancer cells and a drug lidamycin. Furthermore, FCS method established was used to directly detect the fragmentation of DNA extracted from apoptotic cells or in the apoptotic cell lysate. In FCS assay, the single-component model and the multiple-components model were used to fit raw FCS data. The characteristic diffusion time of DNA fragments was used as an important parameter to distinguish the apoptotic status of cells. The obtained data documented that the characteristic diffusion time of DNA fragments from apoptotic cells significantly decreased with an increase of lidamycin concentration, which implied that DNA fragmentation occurred in lidamycin-induced apoptosis. The FCS results are well in line with the data obtained from flow cytometer and gel electrophoresis. Compared to current methods, the method described here is sensitive and simple, and more importantly, our detection volume is less than 1 fL, and the sample requirement can easily be reduced to nL level using a droplets array technology. Therefore, our method probably becomes a high throughput detection platform for early detection of cell apoptosis and screening of apoptosis-based anticancer drugs.
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Affiliation(s)
- Lingao Ruan
- College of Chemistry and Chemical Engineering, State Key Laboratory of Metal Matrix Composites, Shanghai Jiaotong University, Shanghai 200240, People's Republic of China
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Kanamori A, Catrinescu MM, Belisle JM, Costantino S, Levin LA. Retrograde and Wallerian axonal degeneration occur synchronously after retinal ganglion cell axotomy. THE AMERICAN JOURNAL OF PATHOLOGY 2012; 181:62-73. [PMID: 22642911 DOI: 10.1016/j.ajpath.2012.03.030] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2011] [Revised: 03/05/2012] [Accepted: 03/15/2012] [Indexed: 01/23/2023]
Abstract
Axonal injury and degeneration are pivotal pathological events in diseases of the nervous system. In the past decade, it has been recognized that the process of axonal degeneration is distinct from somal degeneration and that axoprotective strategies may be distinct from those that protect the soma. Preserving the cell body via neuroprotection cannot improve function if the axon is damaged, because the soma is still disconnected from its target. Therefore, understanding the mechanisms of axonal degeneration is critical for developing new therapeutic interventions for axonal disease treatment. We combined in vivo imaging with a multilaser confocal scanning laser ophthalmoscope and in vivo axotomy with a diode-pumped solid-state laser to assess the time course of Wallerian and retrograde degeneration of unmyelinated retinal ganglion cell axons in living rats for 4 weeks after intraretinal axotomy. Laser injury resulted in reproducible axon loss both distal and proximal to the site of injury. Longitudinal polarization-sensitive imaging of axons demonstrated that Wallerian and retrograde degeneration occurred synchronously. Neurofilament immunostaining of retinal whole-mounts confirmed axonal loss and demonstrated sparing of adjacent axons to the axotomy site. In vivo fluorescent imaging of axonal transport and photobleaching of labeled axons demonstrated that the laser axotomy model did not affect adjacent axon function. These results are consistent with a shared mechanism for Wallerian and retrograde degeneration.
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Affiliation(s)
- Akiyasu Kanamori
- Maisonneuve-Rosemont Hospital Research Center and Department of Ophthalmology, University of Montreal, Quebec, Canada
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Diurnal, localized exposure of phosphatidylserine by rod outer segment tips in wild-type but not Itgb5-/- or Mfge8-/- mouse retina. Proc Natl Acad Sci U S A 2012; 109:8145-8. [PMID: 22566632 DOI: 10.1073/pnas.1121101109] [Citation(s) in RCA: 115] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
In the mammalian retina, life-long renewal of light-sensitive photoreceptor outer segments (POS) involves circadian shedding of distal rod POS tips and their subsequent phagocytosis by the adjacent retinal pigment epithelium (RPE) every morning after light onset. Molecular mechanisms that promote or synchronize POS tip shedding have thus far remained unknown. Here we examined plasma membrane asymmetry of living POS by quantifying surface exposure of the membrane phospholipid phosphatidylserine (PS) using antibodies, annexin V, and pSIVA (polarity-sensitive indicator of viability and apoptosis), an annexin-based biosensor with switchable states of fluorescence. We found that isolated POS particles possess externalized PS, whose blockade or removal reduces their binding and engulfment by RPE in culture. Imaging of live photoreceptors in freshly dissected mouse retina detected PS externalization restricted to POS tips with discrete boundaries. In wild-type mice, frequency of rod tips exposing PS and length of tips with exposed PS peak shortly after light onset. In contrast, PS-marked POS tips do not vary in mice lacking the diurnal phagocytic rhythm of the RPE due to loss of either the phagocytosis receptor αvβ5 integrin, expressed by the RPE but not by photoreceptors, or its extracellular ligand milk fat globule-EGF factor 8 (MFG-E8). These data identify a molecular distinction, localized PS exposure, that is specific to the surface of rod POS tips. Enhanced PS exposure preceding rod shedding and phagocytosis suggests that surface PS promotes these processes. Moreover, our results demonstrate that the diurnal rhythm of PS demarcation of POS tips is not intrinsic to rod photoreceptors but requires activities of the RPE as well.
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Das S, Powe AM, Baker GA, Valle B, El-Zahab B, Sintim HO, Lowry M, Fakayode SO, McCarroll ME, Patonay G, Li M, Strongin RM, Geng ML, Warner IM. Molecular Fluorescence, Phosphorescence, and Chemiluminescence Spectrometry. Anal Chem 2011; 84:597-625. [DOI: 10.1021/ac202904n] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Susmita Das
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Aleeta M. Powe
- Department of Chemistry, University of Louisville, Louisville, Kentucky 40208, United States
| | - Gary A. Baker
- Department of Chemistry, University of Missouri−Columbia, Columbia, Missouri 65211-7600, United States
| | - Bertha Valle
- Department of Chemistry, Texas Southern University, Houston, Texas 77004, United States
| | - Bilal El-Zahab
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Herman O. Sintim
- Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, United States
| | - Mark Lowry
- Department of Chemistry, Portland State University, Portland, Oregon 97207, United States
| | - Sayo O. Fakayode
- Department of Chemistry, Winston-Salem State University, Winston-Salem, North Carolina 27110, United States
| | - Matthew E. McCarroll
- Department of Chemistry and Biochemistry, Southern Illinois University, Carbondale, Illinois 62901-4409, United States
| | - Gabor Patonay
- Department of Chemistry, Georgia State University, Atlanta, Georgia 30302-4098, United States
| | - Min Li
- Process Development Center, Albemarle Corporation, Baton Rouge, Louisiana 70805, United States
| | - Robert M. Strongin
- Department of Chemistry, Portland State University, Portland, Oregon 97207, United States
| | - Maxwell L. Geng
- Department of Chemistry, University of Iowa, Iowa City, Iowa 52242, United States
| | - Isiah M. Warner
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
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Diemert S, Dolga AM, Tobaben S, Grohm J, Pfeifer S, Oexler E, Culmsee C. Impedance measurement for real time detection of neuronal cell death. J Neurosci Methods 2011; 203:69-77. [PMID: 21963366 DOI: 10.1016/j.jneumeth.2011.09.012] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2011] [Revised: 09/13/2011] [Accepted: 09/15/2011] [Indexed: 02/08/2023]
Abstract
Detection of neuronal cell death is a standard requirement in cell culture models of neurodegenerative diseases. Although plenty of viability assays are available for in vitro applications, most of these are endpoint measurements providing only little information on the kinetics of cell death. Here, we validated the xCELLigence system based on impedance measurement for real-time detection of cell death in a neuronal cell line of immortalized hippocampal neurons (HT-22 cells), neuronal progenitor cells (NPC) and differentiated primary cortical neurons. We found a good correlation between impedance measurements and endpoint viability assays in HT-22 cells and NPC, for detecting proliferation, cell death kinetics and also neuroprotective effects of pharmacological inhibitors of apoptosis. In primary neurons we could not detect dendritic outgrowth during differentiation of the cells. Cell death in primary neurons was detectable by the xCELLigence system, however, the changes in the cell index on the basis of impedance measurements depended to a great extent on the severity of the insult. Cell death induced by ionomycin, e.g. shows as a fast paced process involving a strong cellular disintegration, which allows for impedance-based detection. Cell death accompanied by less pronounced morphological changes like glutamate induced cell death, however, is not well accessible by this approach. In conclusion, our data show that impedance measurement is a convenient and reliable method for the detection of proliferation and kinetics of cell death in neuronal cell lines, whereas this method is less suitable for the assessment of neuronal differentiation and viability of primary neurons.
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Affiliation(s)
- S Diemert
- Institute for Pharmacology and Clinical Pharmacy, Biochemical-Pharmacological Center Marburg, University of Marburg, Karl-von-Frisch Straße 1, 35032 Marburg, Germany.
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Krajewska M, You Z, Rong J, Kress C, Huang X, Yang J, Kyoda T, Leyva R, Banares S, Hu Y, Sze CH, Whalen MJ, Salmena L, Hakem R, Head BP, Reed JC, Krajewski S. Neuronal deletion of caspase 8 protects against brain injury in mouse models of controlled cortical impact and kainic acid-induced excitotoxicity. PLoS One 2011; 6:e24341. [PMID: 21957448 PMCID: PMC3174961 DOI: 10.1371/journal.pone.0024341] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2011] [Accepted: 08/09/2011] [Indexed: 11/25/2022] Open
Abstract
Background Acute brain injury is an important health problem. Given the critical position of caspase 8 at the crossroads of cell death pathways, we generated a new viable mouse line (Ncasp8−/−), in which the gene encoding caspase 8 was selectively deleted in neurons by cre-lox system. Methodology/Principal Findings Caspase 8 deletion reduced rates of neuronal cell death in primary neuronal cultures and in whole brain organotypic coronal slice cultures prepared from 4 and 8 month old mice and cultivated up to 14 days in vitro. Treatments of cultures with recombinant murine TNFα (100 ng/ml) or TRAIL (250 ng/mL) plus cyclohexamide significantly protected neurons against cell death induced by these apoptosis-inducing ligands. A protective role of caspase 8 deletion in vivo was also demonstrated using a controlled cortical impact (CCI) model of traumatic brain injury (TBI) and seizure-induced brain injury caused by kainic acid (KA). Morphometric analyses were performed using digital imaging in conjunction with image analysis algorithms. By employing virtual images of hundreds of brain sections, we were able to perform quantitative morphometry of histological and immunohistochemical staining data in an unbiased manner. In the TBI model, homozygous deletion of caspase 8 resulted in reduced lesion volumes, improved post-injury motor performance, superior learning and memory retention, decreased apoptosis, diminished proteolytic processing of caspases and caspase substrates, and less neuronal degeneration, compared to wild type, homozygous cre, and caspase 8-floxed control mice. In the KA model, Ncasp8−/− mice demonstrated superior survival, reduced seizure severity, less apoptosis, and reduced caspase 3 processing. Uninjured aged knockout mice showed improved learning and memory, implicating a possible role for caspase 8 in cognitive decline with aging. Conclusions Neuron-specific deletion of caspase 8 reduces brain damage and improves post-traumatic functional outcomes, suggesting an important role for this caspase in pathophysiology of acute brain trauma.
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Affiliation(s)
- Maryla Krajewska
- Sanford-Burnham Medical Research Institute, La Jolla, California, United States of America
| | - Zerong You
- Neuroscience Center, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, United States of America
| | - Juan Rong
- Sanford-Burnham Medical Research Institute, La Jolla, California, United States of America
| | - Christina Kress
- Sanford-Burnham Medical Research Institute, La Jolla, California, United States of America
| | - Xianshu Huang
- Sanford-Burnham Medical Research Institute, La Jolla, California, United States of America
| | - Jinsheng Yang
- Neuroscience Center, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, United States of America
| | - Tiffany Kyoda
- Sanford-Burnham Medical Research Institute, La Jolla, California, United States of America
| | - Ricardo Leyva
- Sanford-Burnham Medical Research Institute, La Jolla, California, United States of America
| | - Steven Banares
- Sanford-Burnham Medical Research Institute, La Jolla, California, United States of America
| | - Yue Hu
- Department of Anesthesiology, University of California San Diego, La Jolla, California, United States of America
- VA San Diego Healthcare System, San Diego, California, United States of America
| | - Chia-Hung Sze
- Sanford-Burnham Medical Research Institute, La Jolla, California, United States of America
| | - Michael J. Whalen
- Neuroscience Center, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, United States of America
| | - Leonardo Salmena
- Department of Medical Biophysics, Ontario Cancer Institute, Toronto, Ontario, Canada
| | - Razqallah Hakem
- Department of Medical Biophysics, Ontario Cancer Institute, Toronto, Ontario, Canada
| | - Brian P. Head
- Department of Anesthesiology, University of California San Diego, La Jolla, California, United States of America
| | - John C. Reed
- Sanford-Burnham Medical Research Institute, La Jolla, California, United States of America
- * E-mail: (SK); (JCR)
| | - Stan Krajewski
- Sanford-Burnham Medical Research Institute, La Jolla, California, United States of America
- * E-mail: (SK); (JCR)
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