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Buratti S, Grenzi M, Tortora G, Nastasi SP, Dell'Aglio E, Bassi A, Costa A. Noninvasive In Planta Live Measurements of H 2O 2 and Glutathione Redox Potential with Fluorescent roGFPs-Based Sensors. Methods Mol Biol 2024; 2798:45-64. [PMID: 38587735 DOI: 10.1007/978-1-0716-3826-2_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/09/2024]
Abstract
In this protocol, we present a noninvasive in planta bioimaging technique for the analysis of hydrogen peroxide (H2O2) and glutathione redox potential in adult Arabidopsis thaliana plants. The technique is based on the use of stereo fluorescence microscopy to image A. thaliana plants expressing the two genetically encoded fluorescent sensors roGFP2-Orp1 and Grx1-roGFP2. We provide a detailed step-by-step protocol for performing low magnification imaging with mature plants grown in soil or hydroponic systems. This protocol aims to serve the scientific community by providing an accessible approach to noninvasive in planta bioimaging and data analysis.
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Affiliation(s)
- Stefano Buratti
- Department of Biosciences, Università degli Studi di Milano, Milan, Italy
| | - Matteo Grenzi
- Department of Biosciences, Università degli Studi di Milano, Milan, Italy
| | | | - Sara Paola Nastasi
- Department of Biosciences, Università degli Studi di Milano, Milan, Italy
| | - Elisa Dell'Aglio
- Department of Biosciences, Università degli Studi di Milano, Milan, Italy
| | - Andrea Bassi
- Department of Physics, Politecnico di Milano, Milan, Italy
| | - Alex Costa
- Department of Biosciences, Università degli Studi di Milano, Milan, Italy.
- Institute of Biophysics, National Research Council of Italy (CNR), Milan, Italy.
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2
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Hu H, Dong K, Yan B, Mu Y, Liao Y, Zhang L, Guo S, Xiao X, Wang X. Highly-sensitive and homogenous detection of 8-oxoguanine based DNA oxidative damage by a CRISPR-enhanced structure-switching aptamer assay. Biosens Bioelectron 2023; 239:115588. [PMID: 37597500 DOI: 10.1016/j.bios.2023.115588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Revised: 08/05/2023] [Accepted: 08/09/2023] [Indexed: 08/21/2023]
Abstract
8-oxoguanine (8-oxoG) based DNA damage is the most common type of DNA damage which greatly affect gene expression. Therefore, accurate quantification of 8-oxoG based DNA damage is of high clinical significance. However, current methods for 8-oxoG detection struggle to balance convenience, low cost, and sensitivity. Herein, we have proposed and investigated the shortened crRNA mode of CRISPR-Cas12a system and greatly enhanced its signal-to-noise ratio. Taking advantages of the shortened crRNA mode, we further developed a CRISPR-enhanced structure-switching aptamer assay (CESA) for 8-oxoG. The analytical performance of CESA was thoroughly investigated via detecting free 8-oxoG and 8-oxoG on gDNA. The CESA displayed impressive sensitivity for free 8-oxoG, with detection and quantification limits of 32.3 pM and 0.107 nM. These limits modestly rose to 64.5 pM and 0.215 nM when examining 8-oxoG on gDNA. To demonstrate the clinical practicability and significance of the CESA system, we further applied it to measuring 8-oxoG levels in 7 plasma samples (Cervical carcinoma, 11.87 ± 0.69 nM VS. Healthy control, 2.66 ± 0.42 nM), 24 seminal plasma samples (Asthenospermia, 22.29 ± 7.48 nM VS. Normal sperm, 9.75 ± 3.59 nM), 10 breast-tissue gDNA samples (Breast cancer, 2.77 ± 0.63 nM/μg VS. Healthy control, 0.41 ± 0.09 nM/μg), and 24 sperm gDNA samples (Asthenospermia, 28.62 ± 4.84 VS. Normal sperm, 16.67 ± 3.31). This work not only proposes a novel design paradigm of shortened crRNA for developing CRISPR-Cas12a based biosensors but also offers a powerful tool for detecting 8-oxoG based DNA damage.
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Affiliation(s)
- Hao Hu
- Department of Breast Surgery, Second Hospital of Jilin University, No.4026 Yatai Street, Nanguan District, Changchun, 130041, China; Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Kejun Dong
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China; Department of Obstetrics and Gynecology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Bei Yan
- Ningxia Human Sperm Bank, General Hospital of Ningxia Medical University, Yinchuan, 750004, PR China; Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Yaoqin Mu
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Yangwei Liao
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Lei Zhang
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Songcheng Guo
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Xianjin Xiao
- Department of Breast Surgery, Second Hospital of Jilin University, No.4026 Yatai Street, Nanguan District, Changchun, 130041, China; Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China; Wuhan Huchuang Biotechnology Co, Ltd, No.818 Gaoxin Avenue, Wuhan, 430070, China.
| | - Xinyu Wang
- Department of Breast Surgery, Second Hospital of Jilin University, No.4026 Yatai Street, Nanguan District, Changchun, 130041, China.
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3
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Kayser C, Melkes B, Derieux C, Bock A. Spatiotemporal GPCR signaling illuminated by genetically encoded fluorescent biosensors. Curr Opin Pharmacol 2023; 71:102384. [PMID: 37327640 DOI: 10.1016/j.coph.2023.102384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Revised: 05/04/2023] [Accepted: 05/06/2023] [Indexed: 06/18/2023]
Abstract
G protein-coupled receptors (GPCRs) are ligand-activated cell membrane proteins and represent the most important class of drug targets. GPCRs adopt several active conformations that stimulate different intracellular G proteins (and other transducers) and thereby modulate second messenger levels, eventually resulting in receptor-specific cell responses. It is increasingly accepted that not only the type of active signaling protein but also the duration of its stimulation and the subcellular location from where receptors signal distinctly contribute to the overall cell response. However, the molecular principles governing such spatiotemporal GPCR signaling and their role in disease are incompletely understood. Genetically encoded, fluorescent biosensors-in particular for the GPCR/cAMP signaling axis-have been pivotal to the discovery and molecular understanding of novel concepts in spatiotemporal GPCR signaling. These include GPCR priming, location bias, and receptor-associated independent cAMP nanodomains. Here, we review such technologies that we believe will illuminate the spatiotemporal organization of other GPCR signaling pathways that define the complex signaling architecture of the cell.
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Affiliation(s)
- Charlotte Kayser
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), Robert-Rössle-Straße 10, 13125 Berlin, Germany
| | - Barbora Melkes
- Rudolf-Boehm-Institute of Pharmacology and Toxicology, Medical Faculty, Leipzig University, Härtelstr. 16-18, 04107 Leipzig, Germany
| | - Cécile Derieux
- Rudolf-Boehm-Institute of Pharmacology and Toxicology, Medical Faculty, Leipzig University, Härtelstr. 16-18, 04107 Leipzig, Germany
| | - Andreas Bock
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), Robert-Rössle-Straße 10, 13125 Berlin, Germany; Rudolf-Boehm-Institute of Pharmacology and Toxicology, Medical Faculty, Leipzig University, Härtelstr. 16-18, 04107 Leipzig, Germany.
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4
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Zhu J, Yang B, Peng L, Wu J, Hao H, Lou S. Target-triggered double fluorescent biosensors for rapid and sensitive detection of long-chain perfluorinated compounds using DNA probe and lysozyme fiber. Sci Total Environ 2023; 860:160496. [PMID: 36436631 DOI: 10.1016/j.scitotenv.2022.160496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 11/16/2022] [Accepted: 11/21/2022] [Indexed: 06/16/2023]
Abstract
Perfluorinated compounds (PFCs) are useful man-made chemicals and serve as new emerging organic pollutants due to their environmental and health concerns. Chromatography-mass detection methods often need complex procedure and are also too expensive, so there is a critical demand to develop rapid, inexpensive, easy-to-operate and sensitive methods for PFCs detection. In this work, double fluorescent biosensors ('DT sensor' and 'FT sensor') have been designed to quantitatively detect long-chain perfluorinated compounds (PFCs), due to their strong hydrophobic interaction with DNA probe or lysozyme fiber. The ratio and rapid fluorescence responses offered more obvious signal changes, and high sensitivity with a limit of detection (LOD) of 0.16 μM (98.2 ppb) for perfluorododecanoic acid (PFDoA). For three PFCs with longer perfluoroalkyl chain (CF2), increased detection sensitivity was achieved due to a stronger hydrophobicity. The fluorescent biosensors showed a good selectivity for long-chain PFCs and served as cross-reactive sensors to differentiate three different long-chain PFCs. The biosensors also had robust signal response in tap water or serum samples, and the LOD can be further lowered to pM (ppt) level after sample preconcentration.
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Affiliation(s)
- Jian Zhu
- Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education, College of Chemistry, Xiangtan University, Xiangtan 410005, PR China
| | - Bin Yang
- Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education, College of Chemistry, Xiangtan University, Xiangtan 410005, PR China.
| | - Li Peng
- Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education, College of Chemistry, Xiangtan University, Xiangtan 410005, PR China
| | - Jinwei Wu
- Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education, College of Chemistry, Xiangtan University, Xiangtan 410005, PR China
| | - Huimin Hao
- Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education, College of Chemistry, Xiangtan University, Xiangtan 410005, PR China
| | - Shuyan Lou
- Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education, College of Chemistry, Xiangtan University, Xiangtan 410005, PR China
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Costa CF, Li H, Hussein MAF, Yang Y, Lismont C, Fransen M. Assessment of the Peroxisomal Redox State in Living Cells Using NADPH- and NAD +/NADH-Specific Fluorescent Protein Sensors. Methods Mol Biol 2023; 2643:183-197. [PMID: 36952186 DOI: 10.1007/978-1-0716-3048-8_13] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/24/2023]
Abstract
The pyridine nucleotides NAD(H) and NADP(H) are key molecules in cellular metabolism, and measuring their levels and oxidation states with spatiotemporal precision is of great value in biomedical research. Traditional methods to assess the redox state of these metabolites are intrusive and prohibit live-cell quantifications. This obstacle was surpassed by the development of genetically encoded fluorescent biosensors enabling dynamic measurements with subcellular resolution in living cells. Here, we provide step-by-step protocols to monitor the intraperoxisomal NADPH levels and NAD+/NADH redox state in cellulo by using targeted variants of iNAP1 and SoNar, respectively.
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Affiliation(s)
- Cláudio F Costa
- Department of Cellular and Molecular Medicine, Laboratory of Peroxisome Biology and Intracellular Communication, KU Leuven, Leuven, Belgium
| | - Hongli Li
- Department of Cellular and Molecular Medicine, Laboratory of Peroxisome Biology and Intracellular Communication, KU Leuven, Leuven, Belgium
| | - Mohamed A F Hussein
- Department of Cellular and Molecular Medicine, Laboratory of Peroxisome Biology and Intracellular Communication, KU Leuven, Leuven, Belgium
- Department of Biochemistry, Faculty of Pharmacy, Assiut University, Asyut, Egypt
| | - Yi Yang
- Synthetic Biology and Biotechnology Laboratory, State Key Laboratory of Bioreactor Engineering, Shanghai Collaborative Innovation Center for Biomanufacturing Technology, East China University of Science and Technology, Shanghai, China
- State Key Laboratory of Neuroscience, CAS Center for Excellence in Brain Science, Institute of Neuroscience, Chinese Academy of Sciences, Shanghai, China
| | - Celien Lismont
- Department of Cellular and Molecular Medicine, Laboratory of Peroxisome Biology and Intracellular Communication, KU Leuven, Leuven, Belgium
| | - Marc Fransen
- Department of Cellular and Molecular Medicine, Laboratory of Peroxisome Biology and Intracellular Communication, KU Leuven, Leuven, Belgium.
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Guo X, Wang M, Ma L, Cui Z, Liu Z, Yang H, Liu Y. Carboxyl porphyrin as signal molecule for sensitive fluorescent detection of aflatoxin B 1 via ARGET-ATRP. Spectrochim Acta A Mol Biomol Spectrosc 2022; 280:121535. [PMID: 35752041 DOI: 10.1016/j.saa.2022.121535] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2022] [Revised: 06/03/2022] [Accepted: 06/17/2022] [Indexed: 05/27/2023]
Abstract
In this work, a novel fluorescent biosensor for sensitive detecting of aflatoxin B1 (AFB1) was constructed through activators regenerated by electron transfer for atom transfer radical polymerization (ARGET-ATRP) for the first time. The AFB1 antigen was immobilized on the carboxy magnetic beads (MBs) by forming a sandwich-type "aptamer-antigen-antibody" immune system. Then, acrylamid (AM) was introduced through ARGET-ATRP to provide binding sites for the signaling molecules. Finally, carboxy porphyrins (TPP*) were connected with monomers through an amide bond and fixed on the MBs. Under the optimal experimental conditions, the fluorescence intensity and the logarithm of the concentration of AFB1 showed a good relationship from 100 fg mL-1 to 100 ng mL-1, with the limit of detection (LOD) as low as 8.38 fg mL-1. In addition, the method shows good selectivity and excellent reproducibility. More importantly, the biosensor has applied to the quantitative analysis of AFB1 in four Chinese medicines, and this strategy could potentially serve as a novel means for sensitive detecting of AFB1 in complex matrices.
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Affiliation(s)
- Xiaoyu Guo
- Pharmacy College, Henan University of Chinese Medicine, Zhengzhou 450046, People's Republic of China
| | - Mengli Wang
- Pharmacy College, Henan University of Chinese Medicine, Zhengzhou 450046, People's Republic of China
| | - Lele Ma
- Pharmacy College, Henan University of Chinese Medicine, Zhengzhou 450046, People's Republic of China
| | - Zhenzhen Cui
- Pharmacy College, Henan University of Chinese Medicine, Zhengzhou 450046, People's Republic of China
| | - Zenghui Liu
- Pharmacy College, Henan University of Chinese Medicine, Zhengzhou 450046, People's Republic of China
| | - Huaixia Yang
- Pharmacy College, Henan University of Chinese Medicine, Zhengzhou 450046, People's Republic of China.
| | - Yanju Liu
- Pharmacy College, Henan University of Chinese Medicine, Zhengzhou 450046, People's Republic of China.
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Henderson CA, Rail CA, Butt LE, Vincent HA, Callaghan AJ. Generation of small molecule-binding RNA arrays and their application to fluorogen-binding RNA aptamers. Methods 2019; 167:39-53. [PMID: 31055072 PMCID: PMC7068705 DOI: 10.1016/j.ymeth.2019.04.021] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Revised: 04/04/2019] [Accepted: 04/29/2019] [Indexed: 12/23/2022] Open
Abstract
The discovery and engineering of more and more functions of RNA has highlighted the utility of RNA-targeting small molecules. Recently, several fluorogen-binding RNA aptamers have been developed that have been applied to live cell imaging of RNA and metabolites as RNA tags or biosensors, respectively. Although the design and application of these fluorogen-binding RNA aptamer-based devices is straightforward in theory, in practice, careful optimisation is required. For this reason, high throughput in vitro screening techniques, capable of quantifying fluorogen-RNA aptamer interactions, would be beneficial. We recently developed a method for generating functional-RNA arrays and demonstrated that they could be used to detect fluorogen-RNA aptamer interactions. Specifically, we were able to visualise the interaction between malachite green and the malachite green-binding aptamer. Here we expand this study to demonstrate that functional-RNA arrays can be used to quantify fluorogen-aptamer interactions. As proof-of-concept, we provide detailed protocols for the production of malachite green-binding RNA aptamer and DFHBI-binding Spinach RNA aptamer arrays. Furthermore, we discuss the potential utility of the technology to fluorogen-binding RNA aptamers, including application as a molecular biosensor platform. We anticipate that functional-RNA array technology will be beneficial for a wide variety of biological disciplines.
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Affiliation(s)
- Charlotte A Henderson
- School of Biological Sciences and Institute of Biological and Biomedical Sciences, University of Portsmouth, Portsmouth PO1 2DY, United Kingdom
| | - Callum A Rail
- School of Biological Sciences and Institute of Biological and Biomedical Sciences, University of Portsmouth, Portsmouth PO1 2DY, United Kingdom
| | - Louise E Butt
- School of Biological Sciences and Institute of Biological and Biomedical Sciences, University of Portsmouth, Portsmouth PO1 2DY, United Kingdom
| | - Helen A Vincent
- School of Biological Sciences and Institute of Biological and Biomedical Sciences, University of Portsmouth, Portsmouth PO1 2DY, United Kingdom.
| | - Anastasia J Callaghan
- School of Biological Sciences and Institute of Biological and Biomedical Sciences, University of Portsmouth, Portsmouth PO1 2DY, United Kingdom.
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Zhou Y, Shen S, Lau C, Lu J. A conformational switch-based fluorescent biosensor for homogeneous detection of telomerase activity. Talanta 2019; 199:21-26. [PMID: 30952248 DOI: 10.1016/j.talanta.2019.02.018] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Revised: 01/30/2019] [Accepted: 02/03/2019] [Indexed: 10/27/2022]
Abstract
As a universal tumor biomarker, research on the activity and inhibition of telomerase is of great importance for cancer diagnosis and therapy. Herein, we demonstrate the conformational switch-based fluorescence detection of telomerase activity using a redesigned RNA aptamer Spinach. Briefly, the original Spinach aptamer was extended at its 5' end and folded into an inactive conformation, where association with the small molecule fluorophore, 5-difluoro-4-hydroxybenzylidene imidazolinone (DFHBI) was prevented. Only in the presence of telomerase, (TTAGGG)n repeats were added to the 3' end of the telomerase substrate primer, and the elongation products hybridized with inactive Spinach molecules, triggering its conformational switch and refolding it into the active, DFHBI-binding conformation. Moreover, the fluorescence signal was further amplified through a target recycling circuit, where Ribonuclease H (RNase H) specifically hydrolyzed the phosphodiester bonds of RNA in the DNA-RNA hybrid. The released telomere products could then hybridize to new inactive Spinach molecules and initiate multiple amplification cycles. The proposed fluorescent biosensor presented great performance for telomerase activity detection from 100 to 5 × 104 Hela cells with a detection limit of 100 cells. Besides, this new assay offers a good biosensing platform for differentiation of cancer cell lines from normal cell line and evaluation the inhibition efficiency of telomere-binding ligand, which is of great importance for telomerase-related cancer diagnosis and therapy.
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Affiliation(s)
- Ying Zhou
- School of Pharmacy, Fudan University, 826 Zhangheng Road, Shanghai 201203, China
| | - Shujuan Shen
- School of Pharmacy, Fudan University, 826 Zhangheng Road, Shanghai 201203, China
| | - Choiwan Lau
- School of Pharmacy, Fudan University, 826 Zhangheng Road, Shanghai 201203, China
| | - Jianzhong Lu
- School of Pharmacy, Fudan University, 826 Zhangheng Road, Shanghai 201203, China.
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Steinhorn B, Sartoretto JL, Sorrentino A, Romero N, Kalwa H, Abel ED, Michel T. Insulin-dependent metabolic and inotropic responses in the heart are modulated by hydrogen peroxide from NADPH-oxidase isoforms NOX2 and NOX4. Free Radic Biol Med 2017; 113:16-25. [PMID: 28917508 PMCID: PMC5699944 DOI: 10.1016/j.freeradbiomed.2017.09.006] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Revised: 08/22/2017] [Accepted: 09/09/2017] [Indexed: 01/08/2023]
Abstract
RATIONALE Hydrogen peroxide (H2O2) is a stable reactive oxygen species (ROS) that has long been implicated in insulin signal transduction in adipocytes. However, H2O2's role in mediating insulin's effects on the heart are unknown. OBJECTIVE We investigated the role of H2O2 in activating insulin-dependent changes in cardiac myocyte metabolic and inotropic pathways. The sources of insulin-dependent H2O2 generation were also studied. METHODS AND RESULTS In addition to the canonical role of insulin in modulating cardiac metabolic pathways, we found that insulin also inhibited beta adrenergic-induced increases in cardiac contractility. Catalase and NADPH oxidase (NOX) inhibitors blunted activation of insulin-responsive kinases Akt and mTOR and attenuated beta adrenergic receptor-mediated responses. These insulin responses were lost in a mouse model of type 2 diabetes, suggesting a role for these H2O2-dependent pathways in the diabetic heart. The H2O2-sensitive fluorescent biosensor HyPer revealed rapid increases in cytosolic and caveolar H2O2 concentrations in response to insulin treatment, which were blocked by NOX inhibitors and attenuated in NOX2 KO and NOX4 KO mice. In NOX2 KO cardiac myocytes, insulin-mediated phosphorylation of Akt and mTOR was blocked, while these responses were unaffected in cardiac myocytes from NOX4 KO mice. In contrast, insulin's effects on contractility were lost in cardiac myocytes from NOX4 KO animals but were retained in NOX2 KO mice. CONCLUSIONS These studies identify a proximal point of bifurcation in cardiac insulin signaling through the simultaneous activation of both NOX2 and NOX4. Each NOX isoform generates H2O2 in cardiac myocytes with distinct time courses, with H2O2 derived from NOX2 augmenting Akt-dependent metabolic effects of insulin, while H2O2 from NOX4 blocks beta adrenergic increases in inotropy. These findings suggest that insulin resistance in the diabetic heart may lead to potentially deleterious potentiation of beta adrenergic responses.
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Affiliation(s)
- Benjamin Steinhorn
- Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, United States
| | - Juliano L Sartoretto
- Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, United States
| | - Andrea Sorrentino
- Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, United States
| | - Natalia Romero
- Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, United States
| | - Hermann Kalwa
- Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, United States
| | - E Dale Abel
- University of Iowa School of Medicine, United States
| | - Thomas Michel
- Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, United States.
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Park KS, Lee CY, Kang KS, Park HG. Aptamer-mediated universal enzyme assay based on target-triggered DNA polymerase activity. Biosens Bioelectron 2016; 88:48-54. [PMID: 27499380 DOI: 10.1016/j.bios.2016.07.038] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2016] [Revised: 07/06/2016] [Accepted: 07/11/2016] [Indexed: 11/18/2022]
Abstract
We herein describe an innovative method for a universal fluorescence turn-on enzyme assay, which relies on the target enzyme-triggered DNA polymerase activity. In the first target recognition step, the target enzyme is designed to destabilize detection probe derived from an aptamer specific to DNA polymerase containing the overhang sequence and the complementary blocker DNA, which consequently leads to the recovery of DNA polymerase activity inhibited by the detection probe. This target-triggered polymerase activity is monitored in the second signal transduction step based on primer extension reaction coupled with TaqMan probe. Utilizing this design principle, we have successfully detected the activities of two model enzymes, exonuclease I and uracil DNA glycosylase with high sensitivity and selectivity. Since this strategy is composed of separated target recognition and signal transduction modules, it could be universally employed for the sensitive determination of numerous different target enzymes by simply redesigning the overhang sequence of detection probe, while keeping TaqMan probe-based signal transduction module as a universal signaling tool.
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Affiliation(s)
- Ki Soo Park
- Department of Chemical and Biomolecular Engineering (BK 21+ program), Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 305-338, Republic of Korea; Center for Systems Biology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
| | - Chang Yeol Lee
- Department of Chemical and Biomolecular Engineering (BK 21+ program), Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 305-338, Republic of Korea
| | - Kyoung Suk Kang
- Department of Chemical and Biomolecular Engineering (BK 21+ program), Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 305-338, Republic of Korea
| | - Hyun Gyu Park
- Department of Chemical and Biomolecular Engineering (BK 21+ program), Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 305-338, Republic of Korea.
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