1
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Deal PE, Lee H, Mondal A, Lolicato M, Mendonça PRFD, Black H, Jang S, El-Hilali X, Bryant C, Isacoff EY, Renslo AR, Minor DL. Development of covalent chemogenetic K 2P channel activators. Cell Chem Biol 2024; 31:1305-1323.e9. [PMID: 39029456 DOI: 10.1016/j.chembiol.2024.06.006] [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: 11/01/2023] [Revised: 04/19/2024] [Accepted: 06/19/2024] [Indexed: 07/21/2024]
Abstract
K2P potassium channels regulate excitability by affecting cellular resting membrane potential in the brain, cardiovascular system, immune cells, and sensory organs. Despite their important roles in anesthesia, arrhythmia, pain, hypertension, sleep, and migraine, the ability to control K2P function remains limited. Here, we describe a chemogenetic strategy termed CATKLAMP (covalent activation of TREK family K+ channels to clamp membrane potential) that leverages the discovery of a K2P modulator pocket site that reacts with electrophile-bearing derivatives of a TREK subfamily small-molecule activator, ML335, to activate the channel irreversibly. We show that CATKLAMP can be used to probe fundamental aspects of K2P function, as a switch to silence neuronal firing, and is applicable to all TREK subfamily members. Together, our findings exemplify a means to alter K2P channel activity that should facilitate molecular and systems level studies of K2P function and enable the search for new K2P modulators.
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Affiliation(s)
- Parker E Deal
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA 93858-2330, USA; Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, CA 93858-2330, USA
| | - Haerim Lee
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA 93858-2330, USA
| | - Abhisek Mondal
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA 93858-2330, USA
| | - Marco Lolicato
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA 93858-2330, USA
| | | | - Holly Black
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Seil Jang
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA 93858-2330, USA
| | - Xochina El-Hilali
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, CA 93858-2330, USA
| | - Clifford Bryant
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, CA 93858-2330, USA
| | - Ehud Y Isacoff
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA; Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA 94720, USA; Weill Neurohub, University of California, Berkeley, Berkeley, CA 94720, USA; Molecular Biophysics and Integrated Bio-imaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 USA
| | - Adam R Renslo
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, CA 93858-2330, USA.
| | - Daniel L Minor
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA 93858-2330, USA; Molecular Biophysics and Integrated Bio-imaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 USA; Departments of Biochemistry and Biophysics, and Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA 93858-2330, USA; California Institute for Quantitative Biomedical Research, University of California, San Francisco, San Francisco, CA 93858-2330, USA; Kavli Institute for Fundamental Neuroscience, University of California, San Francisco, San Francisco, CA 93858-2330, USA.
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2
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Yun J, Huang Y, Miller ADC, Chang BL, Baldini L, Dhanabalan KM, Li E, Li H, Mukherjee A. Destabilized reporters for background-subtracted, chemically-gated, and multiplexed deep-tissue imaging. Chem Sci 2024; 15:11108-11121. [PMID: 39027298 PMCID: PMC11253201 DOI: 10.1039/d4sc00377b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Accepted: 05/23/2024] [Indexed: 07/20/2024] Open
Abstract
Tracking gene expression in deep tissues requires genetic reporters that can be unambiguously detected using tissue penetrant techniques. Magnetic resonance imaging (MRI) is uniquely suited for this purpose; however, there is a dearth of reporters that can be reliably linked to gene expression with minimal interference from background tissue signals. Here, we present a conceptually new method for generating background-subtracted, drug-gated, multiplex images of gene expression using MRI. Specifically, we engineered chemically erasable reporters consisting of a water channel, aquaporin-1, fused to destabilizing domains, which are stabilized by binding to cell-permeable small-molecule ligands. We showed that this approach allows for highly specific detection of gene expression through differential imaging. In addition, by engineering destabilized aquaporin-1 variants with orthogonal ligand requirements, it is possible to distinguish distinct subpopulations of cells in mixed cultures. Finally, we demonstrated this approach in a mouse tumor model through differential imaging of gene expression with minimal background.
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Affiliation(s)
- Jason Yun
- Department of Chemistry, University of California Santa Barbara CA 93106 USA
| | - Yimeng Huang
- Department of Chemistry, University of California Santa Barbara CA 93106 USA
| | - Austin D C Miller
- Biomolecular Science and Engineering Graduate Program, University of California Santa Barbara CA 93106 USA
| | - Brandon L Chang
- Department of Molecular, Cell, and Developmental Biology, University of California Santa Barbara CA 93106 USA
| | - Logan Baldini
- Department of Chemical Engineering, University of California Santa Barbara CA 93106 USA
| | - Kaamini M Dhanabalan
- Department of Chemical Engineering, University of California Santa Barbara CA 93106 USA
| | - Eugene Li
- Department of Chemical Engineering, University of California Santa Barbara CA 93106 USA
| | - Honghao Li
- Department of Chemistry, University of California Santa Barbara CA 93106 USA
| | - Arnab Mukherjee
- Department of Chemistry, University of California Santa Barbara CA 93106 USA
- Biomolecular Science and Engineering Graduate Program, University of California Santa Barbara CA 93106 USA
- Department of Chemical Engineering, University of California Santa Barbara CA 93106 USA
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3
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Wang W. Protein-Based Tools for Studying Neuromodulation. ACS Chem Biol 2024; 19:788-797. [PMID: 38581649 PMCID: PMC11129172 DOI: 10.1021/acschembio.4c00037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/08/2024]
Abstract
Neuromodulators play crucial roles in regulating neuronal activity and affecting various aspects of brain functions, including learning, memory, cognitive functions, emotional states, and pain modulation. In this Account, we describe our group's efforts in designing sensors and tools for studying neuromodulation. Our lab focuses on developing new classes of integrators that can detect neuromodulators across the whole brain while leaving a mark for further imaging analysis at high spatial resolution. Our lab also designed chemical- and light-dependent protein switches for controlling peptide activity to potentially modulate the endogenous receptors of the neuromodulatory system in order to study the causal effects of selective neuronal pathways.
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Affiliation(s)
- Wenjing Wang
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, 48109, USA
- Department of Chemistry, University of Michigan, Ann Arbor, MI, 48109, USA
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4
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Terzi F, Knabbe J, Cambridge SB. In Vivo Optical Interrogation of Neuronal Responses to Genetic, Cell Type-Specific Silencing. J Neurosci 2023; 43:8607-8620. [PMID: 37923378 PMCID: PMC10727181 DOI: 10.1523/jneurosci.2253-22.2023] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 05/05/2023] [Accepted: 06/26/2023] [Indexed: 11/07/2023] Open
Abstract
We established a low background, Cre-dependent version of the inducible Tet-On system for fast, cell type-specific transgene expression in vivo Coexpression of a constitutive, Cre-dependent fluorescent marker selectively allowed single-cell analyses before and after inducible, Tet-dependent transgene expression. Here, we used this method for precise, acute manipulation of neuronal activity in the living brain. The goal was to study neuronal network homeostasis at cellular resolution. Single induction of the potassium channel Kir2.1 produced cell type-specific silencing within hours that lasted for at least 3 d. Longitudinal in vivo imaging of spontaneous calcium transients and neuronal morphology demonstrated that prolonged silencing did not alter spine densities or synaptic input strength. Furthermore, selective induction of Kir2.1 in parvalbumin interneurons increased the activity of surrounding neurons in a distance-dependent manner. This high-resolution, inducible interference and interval imaging of individual cells (high I5, HighFive) method thus allows visualizing temporally precise, genetic perturbations of defined cells.SIGNIFICANCE STATEMENT Gene function is studied by KO or overexpression of a specific gene followed by analyses of phenotypic changes. However, being able to predict and analyze exactly those cells in which genetic manipulation will occur is not possible. We combined two prominent transgene overexpression methods to fluorescently highlight the targeted cells appropriately before cell type-specific transgene induction. By inducing a potassium channel that decreases neuronal firing, we investigated how neuronal networks in the living mouse brain possibly compensate swift changes in cellular activities. Unlike in vitro, known compensatory homeostatic mechanisms, such as changes in synapses, were not observed in vivo Overall, we demonstrated with our method rapid genetic manipulation and analysis of neuronal activities as well as precision transgene expression.
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Affiliation(s)
- Firat Terzi
- Heidelberg University, Heidelberg, 69120, Germany
| | | | - Sidney B Cambridge
- Heidelberg University, Heidelberg, 69120, Germany
- Dr. Senckenberg Anatomy, Institute for Anatomy II, Goethe-University Frankfurt am Main, Frankfurt, 60590, Germany
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5
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Deal PE, Lee H, Mondal A, Lolicato M, de Mendonca PRF, Black H, El-Hilali X, Bryant C, Isacoff EY, Renslo AR, Minor DL. Development of covalent chemogenetic K 2P channel activators. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.15.561774. [PMID: 37905049 PMCID: PMC10614804 DOI: 10.1101/2023.10.15.561774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/02/2023]
Abstract
K2P potassium channels regulate excitability by affecting cellular resting membrane potential in the brain, cardiovascular system, immune cells, and sensory organs. Despite their important roles in anesthesia, arrhythmia, pain, hypertension, sleep, and migraine, the ability to control K2P function remains limited. Here, we describe a chemogenetic strategy termed CATKLAMP (Covalent Activation of TREK family K+ channels to cLAmp Membrane Potential) that leverages the discovery of a site in the K2P modulator pocket that reacts with electrophile-bearing derivatives of a TREK subfamily small molecule activator, ML335, to activate the channel irreversibly. We show that the CATKLAMP strategy can be used to probe fundamental aspects of K2P function, as a switch to silence neuronal firing, and is applicable to all TREK subfamily members. Together, our findings exemplify a new means to alter K2P channel activity that should facilitate studies both molecular and systems level studies of K2P function and enable the search for new K2P modulators.
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Affiliation(s)
- Parker E. Deal
- Cardiovascular Research Institute, University of California, San Francisco, California 93858-2330 USA
- Department of Pharmaceutical Chemistry, University of California, San Francisco, California 93858-2330 USA
| | - Haerim Lee
- Cardiovascular Research Institute, University of California, San Francisco, California 93858-2330 USA
| | - Abhisek Mondal
- Cardiovascular Research Institute, University of California, San Francisco, California 93858-2330 USA
| | - Marco Lolicato
- Cardiovascular Research Institute, University of California, San Francisco, California 93858-2330 USA
| | | | - Holly Black
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, California 94720, United States
| | - Xochina El-Hilali
- Department of Pharmaceutical Chemistry, University of California, San Francisco, California 93858-2330 USA
| | - Clifford Bryant
- Department of Pharmaceutical Chemistry, University of California, San Francisco, California 93858-2330 USA
| | - Ehud Y. Isacoff
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, California 94720, United States
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, California 94720, United States
- Weill Neurohub, University of California, Berkeley, Berkeley, California 94720, United States
- Molecular Biophysics and Integrated Bio-imaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 USA
| | - Adam R. Renslo
- Department of Pharmaceutical Chemistry, University of California, San Francisco, California 93858-2330 USA
| | - Daniel L. Minor
- Cardiovascular Research Institute, University of California, San Francisco, California 93858-2330 USA
- Molecular Biophysics and Integrated Bio-imaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 USA
- Departments of Biochemistry and Biophysics, and Cellular and Molecular Pharmacology, University of California, San Francisco, California 93858-2330 USA
- California Institute for Quantitative Biomedical Research, University of California, San Francisco, California 93858-2330 USA
- Kavli Institute for Fundamental Neuroscience, University of California, San Francisco, California 93858-2330 USA
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6
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Yun J, Baldini L, Huang Y, Li E, Li H, Chacko AN, Miller AD, Wan J, Mukherjee A. Engineering ligand stabilized aquaporin reporters for magnetic resonance imaging. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.02.543364. [PMID: 37333371 PMCID: PMC10274688 DOI: 10.1101/2023.06.02.543364] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/20/2023]
Abstract
Imaging transgene expression in live tissues requires reporters that are detectable with deeply penetrant modalities, such as magnetic resonance imaging (MRI). Here, we show that LSAqp1, a water channel engineered from aquaporin-1, can be used to create background-free, drug-gated, and multiplex images of gene expression using MRI. LSAqp1 is a fusion protein composed of aquaporin-1 and a degradation tag that is sensitive to a cell-permeable ligand, which allows for dynamic small molecule modulation of MRI signals. LSAqp1 improves specificity for imaging gene expression by allowing reporter signals to be conditionally activated and distinguished from the tissue background by difference imaging. In addition, by engineering destabilized aquaporin-1 variants with different ligand requirements, it is possible to image distinct cell types simultaneously. Finally, we expressed LSAqp1 in a tumor model and showed successful in vivo imaging of gene expression without background activity. LSAqp1 provides a conceptually unique approach to accurately measure gene expression in living organisms by combining the physics of water diffusion and biotechnology tools to control protein stability.
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Affiliation(s)
- Jason Yun
- Department of Chemistry, University of California, Santa Barbara, CA 93106, USA
| | - Logan Baldini
- Department of Chemical Engineering, University of California, Santa Barbara, CA 93106, USA
| | - Yimeng Huang
- Department of Chemistry, University of California, Santa Barbara, CA 93106, USA
| | - Eugene Li
- Department of Chemical Engineering, University of California, Santa Barbara, CA 93106, USA
| | - Honghao Li
- Department of Chemistry, University of California, Santa Barbara, CA 93106, USA
| | - Asish N. Chacko
- Department of Chemistry, University of California, Santa Barbara, CA 93106, USA
| | - Austin D.C. Miller
- Biomolecular Science and Engineering, University of California, Santa Barbara, CA 93106, USA
| | - Jinyang Wan
- Department of Chemistry, University of California, Santa Barbara, CA 93106, USA
| | - Arnab Mukherjee
- Department of Chemistry, University of California, Santa Barbara, CA 93106, USA
- Department of Chemical Engineering, University of California, Santa Barbara, CA 93106, USA
- Biomolecular Science and Engineering, University of California, Santa Barbara, CA 93106, USA
- Biological Engineering, University of California, Santa Barbara, CA 93106, USA
- Neuroscience Research Institute, University of California, Santa Barbara, CA 93106, USA
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7
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Sood A, Desseigne M, Dev A, Maurizi L, Kumar A, Millot N, Han SS. A Comprehensive Review on Barium Titanate Nanoparticles as a Persuasive Piezoelectric Material for Biomedical Applications: Prospects and Challenges. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023; 19:e2206401. [PMID: 36585372 DOI: 10.1002/smll.202206401] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 11/24/2022] [Indexed: 06/17/2023]
Abstract
Stimulation of cells with electrical cues is an imperative approach to interact with biological systems and has been exploited in clinical practices over a wide range of pathological ailments. This bioelectric interface has been extensively explored with the help of piezoelectric materials, leading to remarkable advancement in the past two decades. Among other members of this fraternity, colloidal perovskite barium titanate (BaTiO3 ) has gained substantial interest due to its noteworthy properties which includes high dielectric constant and excellent ferroelectric properties along with acceptable biocompatibility. Significant progression is witnessed for BaTiO3 nanoparticles (BaTiO3 NPs) as potent candidates for biomedical applications and in wearable bioelectronics, making them a promising personal healthcare platform. The current review highlights the nanostructured piezoelectric bio interface of BaTiO3 NPs in applications comprising drug delivery, tissue engineering, bioimaging, bioelectronics, and wearable devices. Particular attention has been dedicated toward the fabrication routes of BaTiO3 NPs along with different approaches for its surface modifications. This review offers a comprehensive discussion on the utility of BaTiO3 NPs as active devices rather than passive structural unit behaving as carriers for biomolecules. The employment of BaTiO3 NPs presents new scenarios and opportunity in the vast field of nanomedicines for biomedical applications.
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Affiliation(s)
- Ankur Sood
- School of Chemical Engineering, Yeungnam University, 280 Daehak-ro, Gyeongsan, 38541, South Korea
| | - Margaux Desseigne
- Laboratoire Interdisciplinaire Carnot de Bourgogne, UMR 6303 CNRS/Université Bourgogne Franche-Comté, 9 Avenue Alain Savary, BP 47870, Dijon, 21078, France
| | - Atul Dev
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, University of California Davis, 2921 Stockton Boulevard, Sacramento, CA, 95817, USA
| | - Lionel Maurizi
- Laboratoire Interdisciplinaire Carnot de Bourgogne, UMR 6303 CNRS/Université Bourgogne Franche-Comté, 9 Avenue Alain Savary, BP 47870, Dijon, 21078, France
| | - Anuj Kumar
- School of Chemical Engineering, Yeungnam University, 280 Daehak-ro, Gyeongsan, 38541, South Korea
- Institute of Cell Culture, Yeungnam University, 280 Daehak-ro, Gyeongsan, 38541, South Korea
| | - Nadine Millot
- Laboratoire Interdisciplinaire Carnot de Bourgogne, UMR 6303 CNRS/Université Bourgogne Franche-Comté, 9 Avenue Alain Savary, BP 47870, Dijon, 21078, France
| | - Sung Soo Han
- School of Chemical Engineering, Yeungnam University, 280 Daehak-ro, Gyeongsan, 38541, South Korea
- Institute of Cell Culture, Yeungnam University, 280 Daehak-ro, Gyeongsan, 38541, South Korea
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8
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Protease-controlled secretion and display of intercellular signals. Nat Commun 2022; 13:912. [PMID: 35177637 PMCID: PMC8854555 DOI: 10.1038/s41467-022-28623-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Accepted: 02/03/2022] [Indexed: 02/07/2023] Open
Abstract
To program intercellular communication for biomedicine, it is crucial to regulate the secretion and surface display of signaling proteins. If such regulations are at the protein level, there are additional advantages, including compact delivery and direct interactions with endogenous signaling pathways. Here we create a modular, generalizable design called Retained Endoplasmic Cleavable Secretion (RELEASE), with engineered proteins retained in the endoplasmic reticulum and displayed/secreted in response to specific proteases. The design allows functional regulation of multiple synthetic and natural proteins by synthetic protease circuits to realize diverse signal processing capabilities, including logic operation and threshold tuning. By linking RELEASE to additional sensing and processing circuits, we can achieve elevated protein secretion in response to "undruggable" oncogene KRAS mutants. RELEASE should enable the local, programmable delivery of intercellular cues for a broad variety of fields such as neurobiology, cancer immunotherapy and cell transplantation.
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9
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Marino A, Genchi GG, Sinibaldi E, Ciofani G. Piezoelectric Effects of Materials on Bio-Interfaces. ACS APPLIED MATERIALS & INTERFACES 2017; 9:17663-17680. [PMID: 28485910 DOI: 10.1021/acsami.7b04323] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Electrical stimulation of cells and tissues is an important approach of interaction with living matter, which has been traditionally exploited in the clinical practice for a wide range of pathological conditions, in particular, related to excitable tissues. Standard methods of stimulation are, however, often invasive, being based on electrodes and wires used to carry current to the intended site. The possibility to achieve an indirect electrical stimulation, by means of piezoelectric materials, is therefore of outstanding interest for all the biomedical research, and it emerged in the latest decade as a most promising tool in many bioapplications. In this paper, we summarize the most recent achievements obtained by our group and by others in the exploitation of piezoelectric nanoparticles and nanocomposites for cell stimulation, describing the important implications that these studies present in nanomedicine and tissue engineering. A particular attention will be also dedicated to the physical modeling, which can be extremely useful in the description of the complex mechanisms involved in the mechanical/electrical transduction, yet also to gain new insights at the base of the observed phenomena.
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Affiliation(s)
| | | | | | - Gianni Ciofani
- Department of Mechanical and Aerospace Engineering, Politecnico di Torino , Corso Duca degli Abruzzi 24, 10129 Torino, Italy
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10
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Abstract
Protein homeostasis networks are highly regulated systems responsible for maintaining the health and productivity of cells. Whereas therapeutics have been developed to disrupt protein homeostasis, more recently identified techniques have been used to repurpose homeostatic networks to effect degradation of disease-relevant proteins. Here, we review recent advances in the use of small molecules to degrade proteins in a selective manner. First, we highlight all-small-molecule techniques with direct clinical application. Second, we describe techniques that may find broader acceptance in the biomedical research community that require little or no synthetic chemistry. In addition to serving as innovative research tools, these new approaches to control intracellular protein levels offer the potential to develop novel therapeutics targeting proteins that are not currently pharmaceutically vulnerable.
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Affiliation(s)
- Daniel P Bondeson
- Department of Molecular, Cellular, and Developmental Biology, Department of Chemistry, and Department of Pharmacology, Yale University, New Haven, Connecticut 06511;
| | - Craig M Crews
- Department of Molecular, Cellular, and Developmental Biology, Department of Chemistry, and Department of Pharmacology, Yale University, New Haven, Connecticut 06511;
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