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Du Z, Chen G, Li Y, Zheng N, Cheng JX, Yang C. Photoacoustic: A Versatile Nongenetic Method for High-Precision Neuromodulation. Acc Chem Res 2024. [PMID: 38759211 DOI: 10.1021/acs.accounts.4c00119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/19/2024]
Abstract
ConspectusHigh-precision neuromodulation plays a pivotal role in elucidating fundamental principles of neuroscience and treating specific neurological disorders. Optical neuromodulation, enabled by spatial resolution defined by the diffraction limit at the submicrometer scale, is a general strategy to achieve such precision. Optogenetics offers single-neuron spatial resolution with cellular specificity, whereas the requirement of genetic transfection hinders its clinical application. Direct photothermal modulation, an alternative nongenetic optical approach, often associates a large temperature increase with the risk of thermal damage to surrounding tissues.Photoacoustic (also called optoacoustic) neural stimulation is an emerging technology for neural stimulation with the following key features demonstrated. First, the photoacoustic approach demonstrated high efficacy without the need for genetic modification. The generated pulsed ultrasound upon ns laser pulses with energy ranging from a few μJ to tens of μJ is sufficient to activate wild-type neurons. Second, the photoacoustic approach provides sub-100-μm spatial precision. It overcomes the fundamental wave diffraction limit of ultrasound by harnessing the localized ultrasound field generated through light absorption. A spatial precision of 400 μm has been achieved in rodent brains using a fiber-based photoacoustic emitter. Single-cell stimulation in neuronal cultures in vitro and in brain slices ex vivo is achieved using tapered fiber-based photoacoustic emitters. This precision is 10 to 100 times better than for piezo-based low-frequency ultrasound and is essential to pinpoint a specific region or cell population in a living brain. Third, compared to direct photothermal stimulation via temperature increase, photoacoustic stimulation requires a 40 times less laser energy dose to evoke neuron activities and is associated with a minimal temperature increase of less than 1 °C, preventing potential thermal damage to neurons. Fourth, photoacoustics is a versatile approach and can be designed in various platforms aiming at specific applications. Our team has shown the design of fiber-based photoacoustic emitters, photoacoustic nanotransducers, soft biocompatible photoacoustic films, and soft photoacoustic lenses. Since they interact with neurons through ultrasound without the need for direct contact, photoacoustic enables noninvasive transcranial and dura-penetrating brain stimulation without compromising high precision.In this Account, we will first review the basic principles of photoacoustic and discuss the key design elements of PA transducers for neural modulation guided by the principle. We will also highlight how these design goals were achieved from a materials chemistry perspective. The design of different PA interfaces, their unique capability, and their applications in neural systems will be reviewed. In the end, we will discuss the remaining challenges and future perspectives for this technology.
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Affiliation(s)
- Zhiyi Du
- Department of Chemistry, Boston University, Boston, Massachusetts 02215, United States
| | - Guo Chen
- Department of Electrical and Computer Engineering, Boston University, Boston, Massachusetts 02215, United States
| | - Yueming Li
- Department of Electrical and Computer Engineering, Boston University, Boston, Massachusetts 02215, United States
| | - Nan Zheng
- Division of Materials Science and Engineering, Boston University, Boston, Massachusetts 02215, United States
| | - Ji-Xin Cheng
- Department of Electrical and Computer Engineering, Boston University, Boston, Massachusetts 02215, United States
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts 02215, United States
| | - Chen Yang
- Department of Chemistry, Boston University, Boston, Massachusetts 02215, United States
- Department of Electrical and Computer Engineering, Boston University, Boston, Massachusetts 02215, United States
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2
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Celinskis D, Black CJ, Murphy J, Barrios-Anderson A, Friedman NG, Shaner NC, Saab CY, Gomez-Ramirez M, Borton DA, Moore CI. Toward a brighter constellation: multiorgan neuroimaging of neural and vascular dynamics in the spinal cord and brain. Neurophotonics 2024; 11:024209. [PMID: 38725801 PMCID: PMC11079446 DOI: 10.1117/1.nph.11.2.024209] [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] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Revised: 03/18/2024] [Accepted: 03/19/2024] [Indexed: 05/12/2024]
Abstract
Significance Pain comprises a complex interaction between motor action and somatosensation that is dependent on dynamic interactions between the brain and spinal cord. This makes understanding pain particularly challenging as it involves rich interactions between many circuits (e.g., neural and vascular) and signaling cascades throughout the body. As such, experimentation on a single region may lead to an incomplete and potentially incorrect understanding of crucial underlying mechanisms. Aim We aimed to develop and validate tools to enable detailed and extended observation of neural and vascular activity in the brain and spinal cord. The first key set of innovations was targeted to developing novel imaging hardware that addresses the many challenges of multisite imaging. The second key set of innovations was targeted to enabling bioluminescent (BL) imaging, as this approach can address limitations of fluorescent microscopy including photobleaching, phototoxicity, and decreased resolution due to scattering of excitation signals. Approach We designed 3D-printed brain and spinal cord implants to enable effective surgical implantations and optical access with wearable miniscopes or an open window (e.g., for one- or two-photon microscopy or optogenetic stimulation). We also tested the viability for BL imaging and developed a novel modified miniscope optimized for these signals (BLmini). Results We describe "universal" implants for acute and chronic simultaneous brain-spinal cord imaging and optical stimulation. We further describe successful imaging of BL signals in both foci and a new miniscope, the "BLmini," which has reduced weight, cost, and form-factor relative to standard wearable miniscopes. Conclusions The combination of 3D-printed implants, advanced imaging tools, and bioluminescence imaging techniques offers a coalition of methods for understanding spinal cord-brain interactions. Our work has the potential for use in future research into neuropathic pain and other sensory disorders and motor behavior.
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Affiliation(s)
- Dmitrijs Celinskis
- Carney Institute for Brain Science, Providence, Rhode Island, United States
| | | | - Jeremy Murphy
- Carney Institute for Brain Science, Providence, Rhode Island, United States
| | | | - Nina G. Friedman
- Carney Institute for Brain Science, Providence, Rhode Island, United States
| | - Nathan C. Shaner
- University of California San Diego, School of Medicine, La Jolla, California, United States
| | - Carl Y. Saab
- Cleveland Clinic Lerner Research Institute, Neurological Institute, Department of Biomedical Engineering, Cleveland, Ohio, United States
| | - Manuel Gomez-Ramirez
- University of Rochester, School of Arts and Sciences, Rochester, New York, United States
| | - David A. Borton
- Carney Institute for Brain Science, Providence, Rhode Island, United States
- Brown University, School of Engineering, Providence, Rhode Island, United States
- Center for Neurorestoration and Neurotechnology, Providence VA Medical Center, Providence, Rhode Island, United States
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3
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Bassetto CAZ, Pfeffermann J, Yadav R, Strassgschwandtner S, Glasnov T, Bezanilla F, Pohl P. Photolipid excitation triggers depolarizing optocapacitive currents and action potentials. Nat Commun 2024; 15:1139. [PMID: 38326372 PMCID: PMC10850502 DOI: 10.1038/s41467-024-45403-y] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Accepted: 01/22/2024] [Indexed: 02/09/2024] Open
Abstract
Optically-induced changes in membrane capacitance may regulate neuronal activity without requiring genetic modifications. Previously, they mainly relied on sudden temperature jumps due to light absorption by membrane-associated nanomaterials or water. Yet, nanomaterial targeting or the required high infrared light intensities obstruct broad applicability. Now, we propose a very versatile approach: photolipids (azobenzene-containing diacylglycerols) mediate light-triggered cellular de- or hyperpolarization. As planar bilayer experiments show, the respective currents emerge from millisecond-timescale changes in bilayer capacitance. UV light changes photolipid conformation, which awards embedding plasma membranes with increased capacitance and evokes depolarizing currents. They open voltage-gated sodium channels in cells, generating action potentials. Blue light reduces the area per photolipid, decreasing membrane capacitance and eliciting hyperpolarization. If present, mechanosensitive channels respond to the increased mechanical membrane tension, generating large depolarizing currents that elicit action potentials. Membrane self-insertion of administered photolipids and focused illumination allows cell excitation with high spatiotemporal control.
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Affiliation(s)
- Carlos A Z Bassetto
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL, 60637, USA
| | - Juergen Pfeffermann
- Institute of Biophysics, Johannes Kepler University Linz, Gruberstraße 40, 4020, Linz, Austria
| | - Rohit Yadav
- Institute of Biophysics, Johannes Kepler University Linz, Gruberstraße 40, 4020, Linz, Austria
| | | | - Toma Glasnov
- Institute of Chemistry, Karl-Franzens-University, Graz, Austria
| | - Francisco Bezanilla
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL, 60637, USA.
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile.
| | - Peter Pohl
- Institute of Biophysics, Johannes Kepler University Linz, Gruberstraße 40, 4020, Linz, Austria.
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4
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Celinskis D, Black CJ, Murphy J, Barrios-Anderson A, Friedman N, Shaner NC, Saab C, Gomez-Ramirez M, Lipscombe D, Borton DA, Moore CI. Towards a Brighter Constellation: Multi-Organ Neuroimaging of Neural and Vascular Dynamics in the Spinal Cord and Brain. bioRxiv 2023:2023.12.25.573323. [PMID: 38234789 PMCID: PMC10793404 DOI: 10.1101/2023.12.25.573323] [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] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2024]
Abstract
Significance Pain is comprised of a complex interaction between motor action and somatosensation that is dependent on dynamic interactions between the brain and spinal cord. This makes understanding pain particularly challenging as it involves rich interactions between many circuits (e.g., neural and vascular) and signaling cascades throughout the body. As such, experimentation on a single region may lead to an incomplete and potentially incorrect understanding of crucial underlying mechanisms. Aim Here, we aimed to develop and validate new tools to enable detailed and extended observation of neural and vascular activity in the brain and spinal cord. The first key set of innovations were targeted to developing novel imaging hardware that addresses the many challenges of multi-site imaging. The second key set of innovations were targeted to enabling bioluminescent imaging, as this approach can address limitations of fluorescent microscopy including photobleaching, phototoxicity and decreased resolution due to scattering of excitation signals. Approach We designed 3D-printed brain and spinal cord implants to enable effective surgical implantations and optical access with wearable miniscopes or an open window (e.g., for one- or two-photon microscopy or optogenetic stimulation). We also tested the viability for bioluminescent imaging, and developed a novel modified miniscope optimized for these signals (BLmini). Results Here, we describe novel 'universal' implants for acute and chronic simultaneous brain-spinal cord imaging and optical stimulation. We further describe successful imaging of bioluminescent signals in both foci, and a new miniscope, the 'BLmini,' which has reduced weight, cost and form-factor relative to standard wearable miniscopes. Conclusions The combination of 3D printed implants, advanced imaging tools, and bioluminescence imaging techniques offers a new coalition of methods for understanding spinal cord-brain interactions. This work has the potential for use in future research into neuropathic pain and other sensory disorders and motor behavior.
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Affiliation(s)
| | | | - Jeremy Murphy
- Carney Institute for Brain Science, Providence, RI, USA
| | | | - Nina Friedman
- Carney Institute for Brain Science, Providence, RI, USA
| | - Nathan C. Shaner
- University of California San Diego School of Medicine, La Jolla, CA, USA
| | - Carl Saab
- Cleveland Clinic Lerner Research Institute, Department of Biomedical Engineering and Neurological Institute, Cleveland, OH, USA
| | | | | | - David A. Borton
- Carney Institute for Brain Science, Providence, RI, USA
- School of Engineering, Brown University, RI, USA
- Center for Neurorestoration and Neurotechnology, Providence VA Medical Center, RI, USA
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5
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Phillips RS, Baertsch NA. Interdependence of cellular and network properties in respiratory rhythmogenesis. bioRxiv 2023:2023.10.30.564834. [PMID: 37961254 PMCID: PMC10634953 DOI: 10.1101/2023.10.30.564834] [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] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
How breathing is generated by the preBötzinger Complex (preBötC) remains divided between two ideological frameworks, and the persistent sodium current (INaP) lies at the heart of this debate. Although INaP is widely expressed, the pacemaker hypothesis considers it essential because it endows a small subset of neurons with intrinsic bursting or "pacemaker" activity. In contrast, burstlet theory considers INaP dispensable because rhythm emerges from "pre-inspiratory" spiking activity driven by feed-forward network interactions. Using computational modeling, we discover that changes in spike shape can dissociate INaP from intrinsic bursting. Consistent with many experimental benchmarks, conditional effects on spike shape during simulated changes in oxygenation, development, extracellular potassium, and temperature alter the prevalence of intrinsic bursting and pre-inspiratory spiking without altering the role of INaP. Our results support a unifying hypothesis where INaP and excitatory network interactions, but not intrinsic bursting or pre-inspiratory spiking, are critical interdependent features of preBötC rhythmogenesis.
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Affiliation(s)
- Ryan S Phillips
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle WA, USA
| | - Nathan A Baertsch
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle WA, USA
- Pulmonary, Critical Care and Sleep Medicine, Department of Pediatrics, University of Washington, Seattle WA, USA
- Department of Physiology and Biophysics, University of Washington, Seattle WA, USA
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6
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Xu S, Momin M, Ahmed S, Hossain A, Veeramuthu L, Pandiyan A, Kuo CC, Zhou T. Illuminating the Brain: Advances and Perspectives in Optoelectronics for Neural Activity Monitoring and Modulation. Adv Mater 2023; 35:e2303267. [PMID: 37726261 DOI: 10.1002/adma.202303267] [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] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Revised: 05/30/2023] [Indexed: 09/21/2023]
Abstract
Optogenetic modulation of brain neural activity that combines optical and electrical modes in a unitary neural system has recently gained robust momentum. Controlling illumination spatial coverage, designing light-activated modulators, and developing wireless light delivery and data transmission are crucial for maximizing the use of optical neuromodulation. To this end, biocompatible electrodes with enhanced optoelectrical performance, device integration for multiplexed addressing, wireless transmission, and multimodal operation in soft systems have been developed. This review provides an outlook for uniformly illuminating large brain areas while spatiotemporally imaging the neural responses upon optoelectrical stimulation with little artifacts. Representative concepts and important breakthroughs, such as head-mounted illumination, multiple implanted optical fibers, and micro-light-delivery devices, are discussed. Examples of techniques that incorporate electrophysiological monitoring and optoelectrical stimulation are presented. Challenges and perspectives are posed for further research efforts toward high-density optoelectrical neural interface modulation, with the potential for nonpharmacological neurological disease treatments and wireless optoelectrical stimulation.
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Affiliation(s)
- Shumao Xu
- Department of Engineering Science and Mechanics, Center for Neural Engineering, The Pennsylvania State University, Pennsylvania, 16802, USA
| | - Marzia Momin
- Department of Engineering Science and Mechanics, Center for Neural Engineering, The Pennsylvania State University, Pennsylvania, 16802, USA
| | - Salahuddin Ahmed
- Department of Engineering Science and Mechanics, Center for Neural Engineering, The Pennsylvania State University, Pennsylvania, 16802, USA
| | - Arafat Hossain
- Department of Electrical Engineering, The Pennsylvania State University, Pennsylvania, 16802, USA
| | - Loganathan Veeramuthu
- Department of Molecular Science and Engineering, National Taipei University of Technology, Taipei, 10608, Republic of China
| | - Archana Pandiyan
- Department of Molecular Science and Engineering, National Taipei University of Technology, Taipei, 10608, Republic of China
| | - Chi-Ching Kuo
- Department of Molecular Science and Engineering, National Taipei University of Technology, Taipei, 10608, Republic of China
| | - Tao Zhou
- Department of Engineering Science and Mechanics, Center for Neural Engineering, The Pennsylvania State University, Pennsylvania, 16802, USA
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7
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Bassetto CAZ, Pfeffermann J, Yadav R, Strassgschwandtner S, Glasnov T, Bezanilla F, Pohl P. Photolipid excitation triggers depolarizing optocapacitive currents and action potentials. bioRxiv 2023:2023.08.11.552849. [PMID: 37645959 PMCID: PMC10462005 DOI: 10.1101/2023.08.11.552849] [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] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
Optically-induced changes in membrane capacitance may regulate neuronal activity without requiring genetic modifications. Previously, they mainly relied on sudden temperature jumps due to light absorption by membrane-associated nanomaterials or water. Yet, nanomaterial targeting or the required high infrared light intensities obstruct broad applicability. Now, we propose a very versatile approach: photolipids (azobenzene-containing diacylglycerols) mediate light-triggered cellular de- or hyperpolarization. As planar bilayer experiments show, the respective currents emerge from millisecond-timescale changes in bilayer capacitance. UV light changes photolipid conformation, which awards embedding plasma membranes with increased capacitance and evokes depolarizing currents. They open voltage-gated sodium channels in cells, generating action potentials. Blue light reduces the area per photolipid, decreasing membrane capacitance and eliciting hyperpolarization. If present, mechanosensitive channels respond to the increased mechanical membrane tension, generating large depolarizing currents that elicit action potentials. Membrane self-insertion of administered photolipids and focused illumination allows cell excitation with high spatiotemporal control.
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Affiliation(s)
- Carlos A. Z. Bassetto
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL 60637, USA
| | - Juergen Pfeffermann
- Institute of Biophysics, Johannes Kepler University Linz, Gruberstraße 40, 4020 Linz, Austria
| | - Rohit Yadav
- Institute of Biophysics, Johannes Kepler University Linz, Gruberstraße 40, 4020 Linz, Austria
| | | | - Toma Glasnov
- Institute of Chemistry, Karl-Franzens-University, Graz, Austria
| | - Francisco Bezanilla
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL 60637, USA
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Peter Pohl
- Institute of Biophysics, Johannes Kepler University Linz, Gruberstraße 40, 4020 Linz, Austria
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8
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Sung K, Jo S, Lee J, Park JH, Park YH, Moon J, Kim SJ, Jeong J, Lee J, Eom K. Computational analysis of multichannel magnetothermal neural stimulation using magnetic resonator array. Biomed Eng Lett 2023; 13:209-219. [PMID: 37124115 PMCID: PMC10130299 DOI: 10.1007/s13534-023-00267-x] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 01/24/2023] [Accepted: 02/01/2023] [Indexed: 02/12/2023] Open
Abstract
Heating nanoparticles with a magnetic field could facilitate selective remote control of neural activity in deep tissue. However, current magnetothermal stimulation approaches are limited to single-channel stimulation. Here, we investigated various designs for multichannel magnetothermal stimulation based on an array of resonant coils that are driven by a single loop coil. Using a tuning capacitor that allows resonant coils to resonate at the operating frequency, each coil's ON and OFF resonance can be controlled, enabling us to select stimulation channels. We found that smaller inner diameters of resonant coils produce more localized magnetic fields while larger coils produce magnetic fields over a longer distance. The constructed multichannel resonant coil arrays can provide a high enough magnetic field intensity to raise the temperature of nanoparticles by 8 °C when we apply 35.2 W into the loop coil that is spaced 1 mm from the target neurons. This multichannel stimulation using a simple resonant circuit approach would be useful for clinical applications of magnetothermal neural stimulation.
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Affiliation(s)
- Kyungmo Sung
- Department of Electronics Engineering, College of Engineering, Pusan National University, Busan, 46241 Republic of Korea
| | - Seonghoon Jo
- Department of Electronics Engineering, College of Engineering, Pusan National University, Busan, 46241 Republic of Korea
| | - Jaewook Lee
- Department of Electronics Engineering, College of Engineering, Pusan National University, Busan, 46241 Republic of Korea
| | - Jeong Hoan Park
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore, 117583 Singapore
| | - Young Hoon Park
- Department of Electronics Engineering, College of Engineering, Pusan National University, Busan, 46241 Republic of Korea
| | - Jeongjoo Moon
- Department of Electronics Engineering, College of Engineering, Pusan National University, Busan, 46241 Republic of Korea
| | - Sung June Kim
- School of Electrical and Computer Engineering, Seoul National University, Seoul, 08826 Republic of Korea
| | - Joonsoo Jeong
- School of Biomedical Convergence Engineering, Pusan National University, Yangsan, 50612 Republic of Korea
| | - Jonghwan Lee
- Center for Biomedical Engineering, School of Engineering, Brown University, Providence, RI 02912 USA
- Carney Institute for Brain Science, Brown University, Providence, RI 02912 USA
| | - Kyungsik Eom
- Department of Electronics Engineering, College of Engineering, Pusan National University, Busan, 46241 Republic of Korea
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Bassetto CAZ, Pinto BI, Latorre R, Bezanilla F. Ion channel thermodynamics studied with temperature jumps measured at the cell membrane. Biophys J 2023; 122:661-671. [PMID: 36654507 PMCID: PMC9989882 DOI: 10.1016/j.bpj.2023.01.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Revised: 11/29/2022] [Accepted: 01/12/2023] [Indexed: 01/19/2023] Open
Abstract
Perturbing the temperature of a system modifies its energy landscape, thus providing a ubiquitous tool to understand biological processes. Here, we developed a framework to generate sudden temperature jumps (Tjumps) and sustained temperature steps (Tsteps) to study the temperature dependence of membrane proteins under voltage clamp while measuring the membrane temperature. Utilizing the melanin under the Xenopus laevis oocytes membrane as a photothermal transducer, we achieved short Tjumps up to 9°C in less than 1.5 ms and constant Tsteps for durations up to 150 ms. We followed the temperature at the membrane with sub-ms time resolution by measuring the time course of membrane capacitance, which is linearly related to temperature. We applied Tjumps in Kir1.1 isoform b, which reveals a highly temperature-sensitive blockage relief, and characterized the effects of Tsteps on the temperature-sensitive channels TRPM8 and TRPV1. These newly developed approaches provide a general tool to study membrane protein thermodynamics.
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Affiliation(s)
- Carlos A Z Bassetto
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, Illinois
| | - Bernardo I Pinto
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, Illinois
| | - Ramon Latorre
- Centro Interdisciplinario de Neurociencias de Valparaiso, Universidad de Valparaiso, Valparaiso, Chile.
| | - Francisco Bezanilla
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, Illinois; Centro Interdisciplinario de Neurociencias de Valparaiso, Universidad de Valparaiso, Valparaiso, Chile.
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Hall D. Biophysical Reviews: Turning the page from 2022 to 2023. Biophys Rev 2023; 15:1-11. [PMID: 36909962 PMCID: PMC9995637 DOI: 10.1007/s12551-023-01049-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/27/2023] [Indexed: 02/25/2023] Open
Abstract
This Editorial (vol. 15 issue 1-Regular Issue featuring an Issue Focus on the "100th Anniversary of Har Gobind Khorana") first describes the issue contents before providing both, a look back at some journal highlights from 2022, and a look forward to what we can expect from 2023. The Editorial closes with a roundup of new journal access features and an acknowledgement of those supporting the journal.
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Affiliation(s)
- Damien Hall
- WPI Nano Life Science Institute, Kanazawa University, Kakumamachi, Kanazawa, Ishikawa 920-1164 Japan
- Department of Applied Physics, Aalto University, 00076 Aalto, Finland
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11
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Flood MD, Veloz HLB, Hattar S, Carvalho-de-Souza JL. Robust visual cortex evoked potentials (VEP) in Gnat1 and Gnat2 knockout mice. Front Cell Neurosci 2022; 16:1090037. [PMID: 36605613 PMCID: PMC9807669 DOI: 10.3389/fncel.2022.1090037] [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] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Accepted: 12/05/2022] [Indexed: 12/24/2022] Open
Abstract
Intrinsically photosensitive retinal ganglion cells (ipRGCs) express the photopigment melanopsin, imparting to themselves the ability to respond to light in the absence of input from rod or cone photoreceptors. Since their discovery ipRGCs have been found to play a significant role in non-image-forming aspects of vision, including circadian photoentrainment, neuroendocrine regulation, and pupillary control. In the past decade it has become increasingly clear that some ipRGCs also contribute directly to pattern-forming vision, the ability to discriminate shapes and objects. However, the degree to which melanopsin-mediated phototransduction, versus that of rods and cones, contributes to this function is still largely unknown. Earlier attempts to quantify this contribution have relied on genetic knockout models that target key phototransductive proteins in rod and cone photoreceptors, ideally to isolate melanopsin-mediated responses. In this study we used the Gnat1-/-; Gnat2cpfl3/cpfl3 mouse model, which have global knockouts for the rod and cone α-transducin proteins. These genetic modifications completely abolish rod and cone photoresponses under light-adapted conditions, locking these cells into a "dark" state. We recorded visually evoked potentials in these animals and found that they still showed robust light responses, albeit with reduced light sensitivity, with similar magnitudes to control mice. These responses had characteristics that were in line with a melanopsin-mediated signal, including delayed kinetics and increased saturability. Additionally, we recorded electroretinograms in a sub-sample of these mice and were unable to find any characteristic waveform related the activation of photoreceptors or second-order retinal neurons, suggesting ipRGCs as the origin of light responses. Our results show a profound ability for melanopsin phototransduction to directly contribute to the primary pattern-forming visual pathway.
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Affiliation(s)
- Michael D. Flood
- Department of Anesthesiology, College of Medicine, The University of Arizona, Tucson, AZ, United States
| | - Hannah L. B. Veloz
- Department of Anesthesiology, College of Medicine, The University of Arizona, Tucson, AZ, United States
| | - Samer Hattar
- Section on Light and Circadian Rhythms (SLCR), National Institute of Mental Health, Bethesda, MD, United States
| | - Joao L. Carvalho-de-Souza
- Department of Anesthesiology, College of Medicine, The University of Arizona, Tucson, AZ, United States,Department of Physiology, College of Medicine, The University of Arizona, Tucson, AZ, United States,Department of Ophthalmology and Vision Science, College of Medicine, The University of Arizona, Tucson, AZ, United States,BIO5 Institute, The University of Arizona, Tucson, AZ, United States,*Correspondence: Joao L. Carvalho-de-Souza,
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12
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Chaves G, Rodríguez-Corrales JÁ, Solís C. Editorial for 'Issue focus on 2nd Costa Rica biophysics symposium - March 11th-12th, 2021'. Biophys Rev 2022; 14:545-548. [PMID: 35465247 PMCID: PMC9017410 DOI: 10.1007/s12551-022-00947-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Accepted: 03/16/2022] [Indexed: 12/30/2022] Open
Abstract
This Editorial describes both the motivation for, and the five articles appearing in, the Issue Focus dedicated to the 2nd Costa Rica Biophysics Symposium which was held in March 2021. Some recent history about both the symposium and developments in science occurring within Costa Rica is described.
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Affiliation(s)
- Gustavo Chaves
- Center of Physiology, Pathophysiology and Biophysics, Klinikum Nürnberg Medical School-PMU Nürnberg, Nuremberg, Bavaria Germany
| | | | - Christopher Solís
- Department of Physiology and Biophysics, College of Medicine, The University of Illinois at Chicago, Chicago, IL USA
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Abstract
This Issue of Biophysical Reviews (Volume 14, Issue 2) presents a new feature known as an 'Issue Focus' - a contiguous thematic block of five articles placed within a regular Issue format. The current 'Issue Focus' is concerned with the recent developments in Costa Rican biophysical science. The regular aspect of this Issue consists of a 'Meet the Editor' piece by Sabrina Leslie, the first instalment of an ongoing Commentary feature known as the 'Editors' Roundup', and five disparate review articles covering a variety of topics.
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Affiliation(s)
- Damien Hall
- WPI Nano Life Science Institute. Kanazawa University, Kakumamachi, Kanazawa, Ishikawa 920-1164 Japan
- Department of Applied Physics, Aalto University, 00076 Aalto, Finland
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