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Mehidine H, Refregiers M, Jamme F, Varlet P, Juchaux M, Devaux B, Abi Haidar D. Molecular changes tracking through multiscale fluorescence microscopy differentiate Meningioma grades and non-tumoral brain tissues. Sci Rep 2021; 11:3816. [PMID: 33589651 PMCID: PMC7884789 DOI: 10.1038/s41598-020-78678-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 11/19/2020] [Indexed: 11/08/2022] Open
Abstract
Meningioma is the most common primary intracranial extra-axial tumor. Total surgical removal is the standard therapeutic method to treat this type of brain tumors. However, the risk of recurrence depends on the tumor grade and the extent of the resection including the infiltrated dura mater and, if necessary, the infiltrated bone. Therefore, proper resection of all invasive tumor borders without touching eloquent areas is of primordial in order to decrease the risk of recurrence. Nowadays, none of the intraoperative used tools is able to provide a precise real-time histopathological information on the tumor surrounding areas to help the surgeon to achieve a gross total removal. To respond to this problem, our team is developing a multimodal two-photon fluorescence endomicroscope, compatible with the surgeon tool, to better delimitate tumor boundaries, relying on the endogenous fluorescence of brain tissues. In this context, we are building a tissue database in order to specify each brain tissue, whether healthy or tumoral, with its specific optical signature. In this study, we present a multimodal and multiscale optical measurements on non-tumoral control brain tissue obtained in epilepsy surgery patients and several meningioma grades. We investigated tissue auto-fluorescence to track the molecular changes associated with the tumor grade from deep ultra-violet (DUV) to near infrared (NIR) excitation. Micro-spectroscopy, fluorescence lifetime imaging, two-photon fluorescence imaging and Second Harmonic Generation (SHG) imaging were performed. Several optically derived parameters such as collagen crosslinks fluorescence in DUV, SHG emission in NIR and long lifetime intensity fraction of Nicotinamide Adenine Dinucleotide and Flavins were correlated to discriminate cancerous tissue from control one. While collagen response managed to discriminate meningioma grades from control samples with a 100% sensitivity and 90% specificity through a 3D discriminative algorithm.
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Affiliation(s)
- Hussein Mehidine
- Université Paris-Saclay, CNRS/IN2P3, IJCLab, 91405, Orsay, France
- Université de Paris, IJCLab, 91405, Orsay, France
| | | | - Frédéric Jamme
- DISCO Beamline, Synchrotron SOLEIL, 91192, Gif-sur-Yvette, France
| | - Pascale Varlet
- GHU Psychiatrie et Neurosciences, site Sainte-Anne, service de neuropathologie, 75014, Paris, France
- IMA BRAIN, INSERM U894, Centre de Psychiatrie Et de Neurosciences, 75014, Paris, France
- Université de Paris, 75006, Paris, France
| | - Marjorie Juchaux
- Université Paris-Saclay, CNRS/IN2P3, IJCLab, 91405, Orsay, France
| | - Bertrand Devaux
- GHU Psychiatrie et Neurosciences, site Sainte-Anne, service de neuropathologie, 75014, Paris, France
- Université de Paris, 75006, Paris, France
| | - Darine Abi Haidar
- Université Paris-Saclay, CNRS/IN2P3, IJCLab, 91405, Orsay, France.
- Université de Paris, IJCLab, 91405, Orsay, France.
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2
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Hirmiz N, Tsikouras A, Osterlund EJ, Richards M, Andrews DW, Fang Q. Cross-talk reduction in a multiplexed synchroscan streak camera with simultaneous calibration. OPTICS EXPRESS 2019; 27:22602-22614. [PMID: 31510548 DOI: 10.1364/oe.27.022602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 07/14/2019] [Indexed: 06/10/2023]
Abstract
The streak camera is a picosecond resolution photodetector with parallel input capability; however, the degree of multiplexing is limited by crosstalk and temporal uncertainty in the sweeping field. We introduced a fixed time delay between adjacent fibers to reduce crosstalk in the synchroscan mode. The fixed delay and a tunable electronic delay between the input pulse and the synchroscan unit allows robust separation modes between the streaks, while spatial and temporal nonlinearities can be calibrated in. The efficacy of the design is demonstrated through a 100-fold multiplexed confocal fluorescence lifetime imaging microscope in live cells.
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3
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Ranawat H, Pal S, Mazumder N. Recent trends in two-photon auto-fluorescence lifetime imaging (2P-FLIM) and its biomedical applications. Biomed Eng Lett 2019; 9:293-310. [PMID: 31456890 PMCID: PMC6694381 DOI: 10.1007/s13534-019-00119-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 05/30/2019] [Accepted: 06/27/2019] [Indexed: 02/07/2023] Open
Abstract
Two photon fluorescence microscopy and the numerous technical advances to it have served as valuable tools in biomedical research. The fluorophores (exogenous or endogenous) absorb light and emit lower energy photons than the absorption energy and the emission (fluorescence) signal is measured using a fluorescence decay graph. Additionally, high spatial resolution images can be acquired in two photon fluorescence lifetime imaging (2P-FLIM) with improved penetration depth which helps in detection of fluorescence signal in vivo. 2P-FLIM is a non-invasive imaging technique in order to visualize cellular metabolic, by tracking intrinsic fluorophores present in it, such as nicotinamide adenine dinucleotide, flavin adenine dinucleotide and tryptophan etc. 2P-FLIM of these molecules enable the visualization of metabolic alterations, non-invasively. This comprehensive review discusses the numerous applications of 2P-FLIM towards cancer, neuro-degenerative, infectious diseases, and wound healing.
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Affiliation(s)
- Harsh Ranawat
- Department of Biophysics, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal, Karnataka 576104 India
| | - Sagnik Pal
- Department of Biophysics, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal, Karnataka 576104 India
| | - Nirmal Mazumder
- Department of Biophysics, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal, Karnataka 576104 India
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Mehidine H, Sibai M, Poulon F, Pallud J, Varlet P, Zanello M, Devaux B, Abi Haidar D. Multimodal imaging to explore endogenous fluorescence of fresh and fixed human healthy and tumor brain tissues. JOURNAL OF BIOPHOTONICS 2019; 12:e201800178. [PMID: 30203459 DOI: 10.1002/jbio.201800178] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2018] [Accepted: 09/07/2018] [Indexed: 06/08/2023]
Abstract
To complement a project toward label-free optical biopsy and enhanced resection which the overall goal is to develop a multimodal nonlinear endomicroscope, this multimodal approach aims to enhance the accuracy in classifying brain tissue into solid tumor, infiltration and normal tissue intraoperatively. Multiple optical measurements based on one- and two-photon spectral and lifetime autofluorescence, including second harmonic generation imaging, were acquired. As a prerequisite, studying the effect of the time of measurement postexcision on tissue's spectral/lifetime fluorescence properties was warranted, so spectral and lifetime fluorescences of fresh brain tissues were measured using a point-based linear endoscope. Additionally, a comparative study on tissue's optical properties obtained by multimodal nonlinear optical imaging microscope from fresh and fixed tissue was necessary to test whether clinical validation of the nonlinear endomicroscope is feasible by extracting optical signatures from fixed tissue rather than from freshly excised samples. The former is generally chosen for convenience. Results of this study suggest that an hour is necessary postexcision to have consistent fluorescence intensities\lifetimes. The fresh (a,b,c) vs fixed (d,e,f) tissue study indicates that while all optical signals differ after fixation. The characteristic features extracted from one- and two-photon excitation still discriminate normal brain (a,d) cortical tissue, glioblastoma (GBM) (b,e) and metastases (c,f).
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Affiliation(s)
- Hussein Mehidine
- IMNC Laboratory, UMR 8165-CNRS/ IN2P3, Paris-Saclay University, Orsay, France
- Paris Diderot University, Sorbonne Paris Cité, F-75013, Paris, France
| | - Mira Sibai
- IMNC Laboratory, UMR 8165-CNRS/ IN2P3, Paris-Saclay University, Orsay, France
| | - Fanny Poulon
- IMNC Laboratory, UMR 8165-CNRS/ IN2P3, Paris-Saclay University, Orsay, France
| | - Johan Pallud
- Neurosurgery Department, Sainte-Anne Hospital, Paris, France
- IMA BRAIN, INSERMU894, Centre de Psychiatrie et de Neurosciences, Paris, France
- Paris Descartes University, Paris, France
| | - Pascale Varlet
- IMA BRAIN, INSERMU894, Centre de Psychiatrie et de Neurosciences, Paris, France
- Paris Descartes University, Paris, France
- Neuropathology Department, Sainte-Anne Hospital, Paris, France
| | - Marc Zanello
- Neurosurgery Department, Sainte-Anne Hospital, Paris, France
- Paris Descartes University, Paris, France
| | - Bertrand Devaux
- Neurosurgery Department, Sainte-Anne Hospital, Paris, France
- Paris Descartes University, Paris, France
| | - Darine Abi Haidar
- IMNC Laboratory, UMR 8165-CNRS/ IN2P3, Paris-Saclay University, Orsay, France
- Paris Diderot University, Sorbonne Paris Cité, F-75013, Paris, France
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5
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Ramanujan VK. Rapid Assessment of Mitochondrial Complex I Activity and Metabolic Phenotyping of Breast Cancer Cells by NAD(p)H Cytometry. Cytometry A 2018; 95:101-109. [PMID: 30536579 DOI: 10.1002/cyto.a.23681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Revised: 09/11/2018] [Accepted: 10/30/2018] [Indexed: 11/10/2022]
Abstract
Cancer cells are known to display a variety of metabolic reprogramming strategies to fulfill their own growth and proliferative agenda. With the advent of high resolution imaging strategies, metabolomics techniques, and so forth, there is an increasing appreciation of critical role that tumor cell metabolism plays in the overall breast cancer (BC) growth. In this report, we demonstrate a sensitive, flow-cytometry-based assay for rapidly assessing the metabolic phenotypes in isolated suspensions of breast cancer cells. By measuring the temporal variation of NAD(p)H signals in unlabeled, living cancer cells, and by measuring mitochondrial membrane potential {Δψm } in fluorescently labeled cells, we demonstrate that these signals can reliably distinguish the metabolic phenotype of human breast cancer cells and can track the cellular sensitivity to drug candidates. We further show the utility of this metabolic ratio {Δψm /NAD(p)H} in monitoring mitochondrial functional improvement as well as metabolic heterogeneity in primary murine tumor cells isolated from tumor biopsies. Together, these results demonstrate a novel possibility for rapid metabolic functional screening applications as well as a metabolic phenotyping tool for determining drug sensitivity in living cancer cells. © 2018 International Society for Advancement of Cytometry.
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Affiliation(s)
- V Krishnan Ramanujan
- Metabolic Photonics Laboratory, Departments of Surgery and Biomedical Sciences, Cedars-Sinai Medical Center, 8700 Beverly Blvd, Los Angeles, California, 90048
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6
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Abstract
Multicomponent reactions are a valuable tool for the synthesis of functional π-electron systems. Two different approaches can be taken into account for accessing the target structures. In the more conventional scaffold approach an already existing chromophore is coupled with other components to give a complex functional π-system. Here, electronically monotonous components can also be introduced, which may exert synergistic electronic effects within the novel compound. The more demanding chromophore concept generates a complete π-electron system and a scaffold concurrently. The latter approach is particularly stimulating for methodologists since π-systems might be accessible from simple starting materials. This review encompasses the advances in the preparation of functional π-electron systems via multicomponent processes during the past few years, based both on the scaffold and chromophore concepts. Besides the synthetic strategies the most important properties, i.e. redox potentials, absorption and emission maxima or fluorescence quantum yields, of the synthesized molecules are highlighted.
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Affiliation(s)
- Lucilla Levi
- Institut für Organische Chemie und Makromolekulare Chemie, Heinrich-Heine-Universität Düsseldorf, Universitätsstr. 1, D-40225 Düsseldorf, Germany.
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7
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Scaglione CN, Xu Q, Ramanujan VK. Direct measurement of catalase activity in living cells and tissue biopsies. Biochem Biophys Res Commun 2016; 470:192-196. [PMID: 26772884 DOI: 10.1016/j.bbrc.2016.01.026] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Accepted: 01/05/2016] [Indexed: 12/12/2022]
Abstract
Spatiotemporal regulation of enzyme-substrate interactions governs the decision-making steps in biological systems. Enzymes, being functional units of every living cell, contribute to the macromolecular stability of cell survival, proliferation and hence are vital windows to unraveling the biological complexity. Experimental measurements capturing this dynamics of enzyme-substrate interactions in real time add value to this understanding. Furthermore these measurements, upon validation in realistic biological specimens such as clinical biopsies - can further improve our capability in disease diagnostics and treatment monitoring. Towards this direction, we describe here a novel, high-sensitive measurement system for measuring diffusion-limited enzyme-substrate kinetics in real time. Using catalase (enzyme) and hydrogen peroxide (substrate) as the example pair, we demonstrate that this system is capable of direct measurement of catalase activity in vitro and the measured kinetics follows the classical Michaelis-Menten reaction kinetics. We further demonstrate the system performance by measuring catalase activity in living cells and in very small amounts of liver biopsies (down to 1 μg total protein). Catalase-specific enzyme activity is demonstrated by genetic and pharmacological tools. Finally we show the clinically-relevant diagnostic capability of our system by comparing the catalase activities in liver biopsies from young and old mouse (liver and serum) samples. We discuss the potential applicability of this system in clinical diagnostics as well as in intraoperative surgical settings.
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Affiliation(s)
- Christine N Scaglione
- Metabolic Photonics Laboratory, Departments of Surgery and Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
| | - Qijin Xu
- Metabolic Photonics Laboratory, Departments of Surgery and Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
| | - V Krishnan Ramanujan
- Metabolic Photonics Laboratory, Departments of Surgery and Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA.
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8
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Ramanujan VK. Metabolic Plasticity in Cancer Cells: Reconnecting Mitochondrial Function to Cancer Control. JOURNAL OF CELL SCIENCE & THERAPY 2015; 6:211. [PMID: 26457230 PMCID: PMC4598183 DOI: 10.4172/2157-7013.1000211] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Anomalous increase in glycolytic activity defines one of the key metabolic alterations in cancer cells. A realization of this feature has led to critical advancements in cancer detection techniques such as positron emission tomography (PET) as well as a number of therapeutic avenues targeting the key glycolytic steps within a cancer cell. A normal healthy cell's survival relies on a sensitive balance between the primordial glycolysis and a more regulated mitochondrial bioenergetics. The salient difference between these two bioenergetics pathways is that oxygen availability is an obligatory requirement for mitochondrial pathway while glycolysis can function without oxygen. Early observations that some cancer cells up-regulate glycolytic activity even in the presence of oxygen (aerobic glycolysis) led to a hypothesis that such an altered cancer cell metabolism stems from inherent mitochondrial dysfunction. While a general validity of this hypothesis is still being debated, a number of recent research efforts have yielded clarity on the physiological origins of this aerobic glycolysis phenotype in cancer cells. Building on these recent studies, we present a generalized scheme of cancer cell metabolism and propose a novel hypothesis that might rationalize new avenues of cancer intervention.
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Affiliation(s)
- V. Krishnan Ramanujan
- Metabolic Photonics Laboratory, Department of Surgery, Biomedical Imaging Research Institute, Department of Biomedical Sciences, Samuel Oschin Comprehensive Cancer Institute, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048, USA
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9
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Ramanujan VK. Metabolic imaging in multiple time scales. Methods 2013; 66:222-9. [PMID: 24013043 DOI: 10.1016/j.ymeth.2013.08.027] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2013] [Revised: 08/13/2013] [Accepted: 08/23/2013] [Indexed: 10/26/2022] Open
Abstract
We report here a novel combination of time-resolved imaging methods for probing mitochondrial metabolism in multiple time scales at the level of single cells. By exploiting a mitochondrial membrane potential reporter fluorescence we demonstrate the single cell metabolic dynamics in time scales ranging from microseconds to seconds to minutes in response to glucose metabolism and mitochondrial perturbations in real time. Our results show that in comparison with normal human mammary epithelial cells, the breast cancer cells display significant alterations in metabolic responses at all measured time scales by single cell kinetics, fluorescence recovery after photobleaching and by scaling analysis of time-series data obtained from mitochondrial fluorescence fluctuations. Furthermore scaling analysis of time-series data in living cells with distinct mitochondrial dysfunction also revealed significant metabolic differences thereby suggesting the broader applicability (e.g. in mitochondrial myopathies and other metabolic disorders) of the proposed strategies beyond the scope of cancer metabolism. We discuss the scope of these findings in the context of developing portable, real-time metabolic measurement systems that can find applications in preclinical and clinical diagnostics.
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Affiliation(s)
- V Krishnan Ramanujan
- Metabolic Photonics Laboratory, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Suite D6067, Los Angeles, CA 90048, USA; Department of Surgery, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048, USA; Department of Biomedical Sciences, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048, USA; Biomedical Imaging Research Institute, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048, USA.
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10
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Yaseen MA, Sakadžić S, Wu W, Becker W, Kasischke KA, Boas DA. In vivo imaging of cerebral energy metabolism with two-photon fluorescence lifetime microscopy of NADH. BIOMEDICAL OPTICS EXPRESS 2013; 4:307-21. [PMID: 23412419 PMCID: PMC3567717 DOI: 10.1364/boe.4.000307] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2012] [Revised: 01/17/2013] [Accepted: 01/17/2013] [Indexed: 05/04/2023]
Abstract
Minimally invasive, specific measurement of cellular energy metabolism is crucial for understanding cerebral pathophysiology. Here, we present high-resolution, in vivo observations of autofluorescence lifetime as a biomarker of cerebral energy metabolism in exposed rat cortices. We describe a customized two-photon imaging system with time correlated single photon counting detection and specialized software for modeling multiple-component fits of fluorescence decay and monitoring their transient behaviors. In vivo cerebral NADH fluorescence suggests the presence of four distinct components, which respond differently to brief periods of anoxia and likely indicate different enzymatic formulations. Individual components show potential as indicators of specific molecular pathways involved in oxidative metabolism.
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Affiliation(s)
- Mohammad A. Yaseen
- Optics Division, MGH/MIT/HMS Athinoula A. Martinos Center for
Biomedical Imaging, Massachusetts General Hospital/Harvard Medical School, Charlestown,
Massachusetts 02129, USA
| | - Sava Sakadžić
- Optics Division, MGH/MIT/HMS Athinoula A. Martinos Center for
Biomedical Imaging, Massachusetts General Hospital/Harvard Medical School, Charlestown,
Massachusetts 02129, USA
| | - Weicheng Wu
- Optics Division, MGH/MIT/HMS Athinoula A. Martinos Center for
Biomedical Imaging, Massachusetts General Hospital/Harvard Medical School, Charlestown,
Massachusetts 02129, USA
| | - Wolfgang Becker
- Becker & Hickl GmbH, Nahmitzer Damm 30, 12277 Berlin,
Germany
| | - Karl A. Kasischke
- Department of Neurology, University of Ulm Medical Center, Oberer
Eselsberg 45, 89075 Ulm, Germany
| | - David A. Boas
- Optics Division, MGH/MIT/HMS Athinoula A. Martinos Center for
Biomedical Imaging, Massachusetts General Hospital/Harvard Medical School, Charlestown,
Massachusetts 02129, USA
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11
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Suhane S, Kanzaki H, Arumugaswami V, Murali R, Ramanujan VK. Mitochondrial NDUFS3 regulates the ROS-mediated onset of metabolic switch in transformed cells. Biol Open 2013; 2:295-305. [PMID: 23519235 PMCID: PMC3603411 DOI: 10.1242/bio.20133244] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2012] [Accepted: 12/06/2012] [Indexed: 12/22/2022] Open
Abstract
Aerobic glycolysis in transformed cells is an unique metabolic phenotype characterized by a hyperactivated glycolytic pathway even in the presence of oxygen. It is not clear if the onset of aerobic glycolysis is regulated by mitochondrial dysfunction and, if so, what the metabolic windows of opportunity available to control this metabolic switch (mitochondrial to glycolytic) landscape are in transformed cells. Here we report a genetically-defined model system based on the gene-silencing of a mitochondrial complex I subunit, NDUFS3, where we demonstrate the onset of metabolic switch in isogenic human embryonic kidney cells by differential expression of NDUFS3. By means of extensive metabolic characterization, we demonstrate that NDUFS3 gene silencing systematically introduces mitochondrial dysfunction thereby leading to the onset of aerobic glycolysis in a manner dependent on NDUFS3 protein levels. Furthermore, we show that the sustained imbalance in free radical dynamics is a necessary condition to sustain the observed metabolic switch in cell lines with the most severe NDUFS3 suppression. Together, our data reveal a novel role for mitochondrial complex I subunit NDUFS3 in regulating the degree of mitochondrial dysfunction in living cells, thereby setting a “metabolic threshold” for the observation of aerobic glycolysis phenotype within the confines of mitochondrial dysfunction.
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Affiliation(s)
- Sonal Suhane
- Metabolic Photonics Laboratory, Cedars-Sinai Medical Center , 8700 Beverly Boulevard, Davis 6066, Los Angeles, CA 90048 , USA ; Department of Surgery, Cedars-Sinai Medical Center , 8700 Beverly Boulevard, Davis 6066, Los Angeles, CA 90048 , USA
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12
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Al-Awadi NA, Ibrahim MR, Elnagdi MH, John E, Ibrahim YA. Enaminones in a multicomponent synthesis of 4-aryldihydropyridines for potential applications in photoinduced intramolecular electron-transfer systems. Beilstein J Org Chem 2012; 8:441-7. [PMID: 22509215 PMCID: PMC3326623 DOI: 10.3762/bjoc.8.50] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2012] [Accepted: 03/07/2012] [Indexed: 11/23/2022] Open
Abstract
An efficient three component reaction with enaminones, primary amines and aldehydes resulted in easy access to 1,4-dihydropyridines with different substituents at the 1-, 3-, 4- and 5-positions. Microwaves improved the reaction yield, reducing also considerably the reaction time and the amount of solvent used. Chiral primary amines gave chiral 1-substituted-1,4-dihydropyridines. The 4-(1-naphthyl) and 4-(phenanthren-9-yl)dihydropyridine derivatives exhibited an interesting photoluminescence behavior, which suggests their potential application as suitable photoinduced intramolecular electron-transfer systems.
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Affiliation(s)
- Nouria A Al-Awadi
- Chemistry Department, Faculty of Science, Kuwait University, P.O. Box 5969, Safat 13060, Kuwait
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13
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Palero JA, Bader AN, de Bruijn HS, der Ploeg van den Heuvel AV, Sterenborg HJCM, Gerritsen HC. In vivo monitoring of protein-bound and free NADH during ischemia by nonlinear spectral imaging microscopy. BIOMEDICAL OPTICS EXPRESS 2011; 2:1030-9. [PMID: 21559117 PMCID: PMC3087562 DOI: 10.1364/boe.2.001030] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2011] [Revised: 03/19/2011] [Accepted: 03/29/2011] [Indexed: 05/20/2023]
Abstract
Nonlinear spectral imaging microscopy (NSIM) allows simultaneous morphological and spectroscopic investigation of intercellular events within living animals. In this study we used NSIM for in vivo time-lapse in-depth spectral imaging and monitoring of protein-bound and free reduced nicotinamide adenine dinucleotide (NADH) in mouse keratinocytes following total acute ischemia for 3.3 h at ~3 min time intervals. The high spectral resolution of NSIM images allows discrimination between the two-photon excited fluorescence emission of protein-bound and free NAD(P)H by applying linear spectral unmixing to the spectral image data. Results reveal the difference in the dynamic response between protein-bound and free NAD(P)H to ischemia-induced hypoxia/anoxia. Our results demonstrate the capability of nonlinear spectral imaging microscopy in unraveling dynamic cellular metabolic events within living animals for long periods of time.
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Affiliation(s)
- Jonathan A. Palero
- Molecular BioPhysics, Utrecht University, 3584 CC Utrecht, The Netherlands
- Currently with ICFO-Institut de Ciències Fotòniques, Mediterranean Technology Park, 08860 Castelldefels (Barcelona), Spain
| | - Arjen N. Bader
- Molecular BioPhysics, Utrecht University, 3584 CC Utrecht, The Netherlands
| | - Henriëtte S. de Bruijn
- Department of Radiation Oncology,Center of Optical Diagnostics and Therapy, Erasmus Medical Center,3008 AE Rotterdam, The Netherlands
| | | | - Henricus J. C. M. Sterenborg
- Department of Radiation Oncology,Center of Optical Diagnostics and Therapy, Erasmus Medical Center,3008 AE Rotterdam, The Netherlands
| | - Hans C. Gerritsen
- Molecular BioPhysics, Utrecht University, 3584 CC Utrecht, The Netherlands
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14
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Pande P, Jo JA. Automated analysis of fluorescence lifetime imaging microscopy (FLIM) data based on the Laguerre deconvolution method. IEEE Trans Biomed Eng 2010; 58:172-81. [PMID: 20934946 DOI: 10.1109/tbme.2010.2084086] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
In fluorescence lifetime imaging microscopy (FLIM), fluorescence time decay at each pixel of the imaged sample are measured. Every recorded fluorescence decay corresponds to the time convolution of the instrument response with the intrinsic fluorescence impulse response function (IRF), from which the sample fluorescence lifetime is determined. To estimate the IRF, the instrument response thus needs to be deconvolved from the recorded fluorescence decay. We have recently introduced a novel FLIM time-deconvolution method based on the linear expansion of the fluorescence decays on an orthonormal Laguerre basis. Since this method allows simultaneous estimation of the IRFs at all pixels, it performs at least two orders of magnitude faster than standard algorithms. In its original implementation, however, the Laguerre basis, determined by the Laguerre parameter α, is selected using a heuristic approach. Here, we present an automated implementation, whereby the Laguerre parameter α is treated as a free parameter within a nonlinear least squares optimization scheme. The new implementation combines the unmatched inherent computational speed of the Laguerre deconvolution method with a systematic model selection approach. This method will thus facilitate applications of FLIM requiring automatic estimation of the spatial distribution of fluorescence lifetimes, such as in in vivo tissue FLIM imaging.
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Affiliation(s)
- Paritosh Pande
- Department of Biomedical Engineering, Texas A&M University, College Station, TX 77943, USA.
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15
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Joshi S, Agarwal S. The proposed role of optical sensing in translational stroke research. Ann N Y Acad Sci 2010; 1199:149-57. [PMID: 20633120 DOI: 10.1111/j.1749-6632.2009.05381.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The past three decades of clinical disappointments in treating stroke must compel us to rethink our strategy. Given the enormous complexity of the clinical disease, the "one size fits all" approach to stroke treatment is unlikely to succeed. The effective treatment of stroke aimed at reversing ischemic injury will require monitoring of tissue injury and response to therapeutic interventions, perhaps the use of multiple drugs, sequentially administered in a timely manner. The proposed sequential intra-arterial therapy for stroke (SITS) relies on the development of novel intra-arterial treatments of ischemic brain injury in the magnetic resonance imaging environment. However, translating SITS protocol from bench to bedside could greatly benefit from the advances in optical technologies. Compared to magnetic resonance imaging, optical sensing technology promises to be quicker, cheaper, simpler, and more versatile, and thus is ideally suited for investigating the fast kinetics and monitoring the pharmacological effects of intra-arterial drugs.
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16
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Affiliation(s)
- Mikhail Y. Berezin
- Department of Radiology, Washington University School of Medicine, 4525 Scott Ave, St. Louis, USA, Tel. 314-747-0701, 314-362-8599, fax 314-747-5191
| | - Samuel Achilefu
- Department of Radiology, Washington University School of Medicine, 4525 Scott Ave, St. Louis, USA, Tel. 314-747-0701, 314-362-8599, fax 314-747-5191
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Preclinical evaluation of nuclear morphometry and tissue topology for breast carcinoma detection and margin assessment. Breast Cancer Res Treat 2010; 126:345-54. [PMID: 20446030 DOI: 10.1007/s10549-010-0914-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2010] [Accepted: 04/21/2010] [Indexed: 10/19/2022]
Abstract
Prevention and early detection of breast cancer are the major prophylactic measures taken to reduce the breast cancer related mortality and morbidity. Clinical management of breast cancer largely relies on the efficacy of the breast-conserving surgeries and the subsequent radiation therapy. A key problem that limits the success of these surgeries is the lack of accurate, real-time knowledge about the positive tumor margins in the surgically excised tumors in the operating room. This leads to tumor recurrence and, hence, the need for repeated surgeries. Current intraoperative techniques such as frozen section pathology or touch imprint cytology severely suffer from poor sampling and non-optimal detection sensitivity. Even though histopathology analysis can provide information on positive tumor margins post-operatively (~2-3 days), this information is of no immediate utility in the operating rooms. In this article, we propose a novel image analysis method for tumor margin assessment based on nuclear morphometry and tissue topology and demonstrate its high sensitivity/specificity in preclinical animal model of breast carcinoma. The method relies on imaging nuclear-specific fluorescence in the excised surgical specimen and on extracting nuclear morphometric parameters (size, number, and area fraction) from the spatial distribution of the observed fluorescence in the tissue. We also report the utility of tissue topology in tumor margin assessment by measuring the fractal dimension in the same set of images. By a systematic analysis of multiple breast tissues specimens, we show here that the proposed method is not only accurate (~97% sensitivity and 96% specificity) in thin sections, but also in three-dimensional (3D) thick tissues that mimic the realistic lumpectomy specimens. Our data clearly precludes the utility of nuclear size as a reliable diagnostic criterion for tumor margin assessment. On the other hand, nuclear area fraction addresses this issue very effectively since it is a combination of both nuclear size and count in any given region of the analyzed image, and thus yields high sensitivity and specificity (~97%) in tumor detection. This is further substantiated by an independent parameter, fractal dimension, based on the tissue topology. Although the basic definition of cancer as an uncontrolled cell growth entails a high nuclear density in tumor regions, a simple but systematic exploration of nuclear distribution in thick tissues by nuclear morphometry and tissue topology as performed in this study has never been carried out, to the best of our knowledge. We discuss the practical aspects of implementing this imaging approach in automated tissue sampling scenario where the accuracy of tumor margin assessment can be significantly increased by scanning the entire surgical specimen rather than sampling only a few sections as in current histopathology analysis.
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Thomas P, Pande P, Clubb F, Adame J, Jo JA. Biochemical Imaging of Human Atherosclerotic Plaques with Fluorescence Lifetime Angioscopy. Photochem Photobiol 2010; 86:727-31. [DOI: 10.1111/j.1751-1097.2010.00707.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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19
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Van Noorden CJF. Imaging enzymes at work: metabolic mapping by enzyme histochemistry. J Histochem Cytochem 2010; 58:481-97. [PMID: 20124092 DOI: 10.1369/jhc.2010.955518] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
For the understanding of functions of proteins in biological and pathological processes, reporter molecules such as fluorescent proteins have become indispensable tools for visualizing the location of these proteins in intact animals, tissues, and cells. For enzymes, imaging their activity also provides information on their function or functions, which does not necessarily correlate with their location. Metabolic mapping enables imaging of activity of enzymes. The enzyme under study forms a reaction product that is fluorescent or colored by conversion of either a fluorogenic or chromogenic substrate or a fluorescent substrate with different spectral characteristics. Most chromogenic staining methods were developed in the latter half of the twentieth century but still find new applications in modern cell biology and pathology. Fluorescence methods have rapidly evolved during the last decade. This review critically evaluates the methods that are available at present for metabolic mapping in living animals, unfixed cryostat sections of tissues, and living cells, and refers to protocols of the methods of choice.
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Affiliation(s)
- Cornelis J F Van Noorden
- Department of Cell Biology and Histology, Academic Medical Center, Meibergdreef 15, 1105 AZ Amsterdam, The Netherlands.
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Jimenez AJ, Fagnoni M, Mella M, Albini A. Photoinduced electron and energy transfer in aryldihydropyridines. J Org Chem 2009; 74:6615-22. [PMID: 19642692 DOI: 10.1021/jo9010816] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Dimethyl 2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylates (Hantzsch DHPs) fluoresce weakly in fluid solution. However, these compounds exhibit an efficient fluorescence both in a viscous medium (glycerin) at room temperature and in a glassy matrix at 77 K (but no phosphorescence, since ISC is negligible). DHPs bearing an aryl group in position 4 have been synthesized. These contain two different pi systems separated by an sp(3) carbon (DHP-Ar dyads). The occurrence of energy and electron transfer processes between the chromophores is investigated through luminescence measurements. In particular, when (3)Ar emits at a slow rate (e.g., Ar = phenanthryl) or not at all (Ar = nitrophenyl) the intradyad forward/backward electron transfer sequence offers a path for arriving at the DHP-localized triplet and the corresponding phosphorescence is observed. When (3)Ar emits at a faster rate (Ar = acylphenyl), the phosphorescence from either of the two localized triplets, (3)Ar or (3)DHP, can be observed depending on lambda(exc). When the aryl group has a triplet energy lower than that of (3)DHP, this functions as emitting (4-cyano-1-naphthyl) or nonemitting (MeO(2)CCH horizontal lineCHC(6)H(4)) energy sink. The results document the possibility of building tailor-made Hantzsch aryldihydropyridines as versatile photoactivated dyads.
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Affiliation(s)
- Angel J Jimenez
- Department of Organic Chemistry, University of Pavia, v. Taramelli 10, 27100 Pavia, Italy
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