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Krogman WL, Woodard T, McKay RSF. Anesthetic Mechanisms: Synergistic Interactions With Lipid Rafts and Voltage-Gated Sodium Channels. Anesth Analg 2024; 139:92-106. [PMID: 37968836 DOI: 10.1213/ane.0000000000006738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2023]
Abstract
Despite successfully utilizing anesthetics for over 150 years, the mechanism of action remains relatively unknown. Recent studies have shown promising results, but due to the complex interactions between anesthetics and their targets, there remains a clear need for further mechanistic research. We know that lipophilicity is directly connected to anesthetic potency since lipid solubility relates to anesthetic partition into the membrane. However, clinically relevant concentrations of anesthetics do not significantly affect lipid bilayers but continue to influence various molecular targets. Lipid rafts are derived from liquid-ordered phases of the plasma membrane that contain increased concentrations of cholesterol and sphingomyelin and act as staging platforms for membrane proteins, including ion channels. Although anesthetics do not perturb membranes at clinically relevant concentrations, they have recently been shown to target lipid rafts. In this review, we summarize current research on how different types of anesthetics-local, inhalational, and intravenous-bind and affect both lipid rafts and voltage-gated sodium channels, one of their major targets, and how those effects synergize to cause anesthesia and analgesia. Local anesthetics block voltage-gated sodium channel pores while also disrupting lipid packing in ordered membranes. Inhalational anesthetics bind to the channel pore and the voltage-sensing domain while causing an increase in the number, size, and diameter of lipid rafts. Intravenous anesthetics bind to the channel primarily at the voltage-sensing domain and the selectivity filter, while causing lipid raft perturbation. These changes in lipid nanodomain structure possibly give proteins access to substrates that have translocated as a result of these structural alterations, resulting in lipid-driven anesthesia. Overall, anesthetics can impact channel activity either through direct interaction with the channel, indirectly through the lipid raft, or both. Together, these result in decreased sodium ion flux into the cell, disrupting action potentials and producing anesthetic effects. However, more research is needed to elucidate the indirect mechanisms associated with channel disruption through the lipid raft, as not much is known about anionic lipid products and their influence over voltage-gated sodium channels. Anesthetics' effect on S-palmitoylation, a promising mechanism for direct and indirect influence over voltage-gated sodium channels, is another auspicious avenue of research. Understanding the mechanisms of different types of anesthetics will allow anesthesiologists greater flexibility and more specificity when treating patients.
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Affiliation(s)
- William L Krogman
- From the Department of Anesthesiology, University of Kansas School of Medicine - Wichita, Wichita, Kansas
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2
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Alobeedallah H, Cornell B, Ghazal M, Coster H. The Effect of Benzyl Alcohol on the Voltage-Current Characteristics of Tethered Lipid Bilayers. J Membr Biol 2023; 256:423-431. [PMID: 37728833 DOI: 10.1007/s00232-023-00291-z] [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: 11/13/2022] [Accepted: 08/21/2023] [Indexed: 09/21/2023]
Abstract
In this study a lipid bilayer membrane model was used in which the bilayer is tethered to a solid substrate with molecular tethers. Voltage-current (V-I) measurements of the tethered bilayer membranes (tBLM) and tBLM with benzyl alcohol (BZA) incorporated in their structures, were measured using triangular voltage ramps of 0-500 mV. The temperature dependence of the conductance deduced from the V-I measurements are described. An evaluation of the activation energies for electrical conductance showed that BZA decreased the activation/ Born energies for ionic conduction of tethered lipid membranes. It is concluded that BZA increased the average pore radius of the tBLM.
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Affiliation(s)
- Hadeel Alobeedallah
- Department of Electrical, Computer and Biomedical Engineering, Abu Dhabi University, Abu Dhabi, United Arab Emirates.
| | - Bruce Cornell
- SDx Tethered Membranes Pty Ltd, Roseville, Sydney, 2069, Australia
| | - Mohammed Ghazal
- Department of Electrical, Computer and Biomedical Engineering, Abu Dhabi University, Abu Dhabi, United Arab Emirates
| | - Hans Coster
- School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, 2006, Australia
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Jang IS, Nakamura M, Nonaka K, Noda M, Kotani N, Katsurabayashi S, Nagami H, Akaike N. Protein Kinase A Is Responsible for the Presynaptic Inhibition of Glycinergic and Glutamatergic Transmissions by Xenon in Rat Spinal Cord and Hippocampal CA3 Neurons. J Pharmacol Exp Ther 2023; 386:331-343. [PMID: 37391223 DOI: 10.1124/jpet.123.001599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 04/16/2023] [Accepted: 06/09/2023] [Indexed: 07/02/2023] Open
Abstract
The effects of a general anesthetic xenon (Xe) on spontaneous, miniature, electrically evoked synaptic transmissions were examined using the "synapse bouton preparation," with which we can clearly evaluate pure synaptic responses and accurately quantify pre- and postsynaptic transmissions. Glycinergic and glutamatergic transmissions were investigated in rat spinal sacral dorsal commissural nucleus and hippocampal CA3 neurons, respectively. Xe presynaptically inhibited spontaneous glycinergic transmission, the effect of which was resistant to tetrodotoxin, Cd2+, extracellular Ca2+, thapsigargin (a selective sarcoplasmic/endoplasmic reticulum Ca2+-ATPase inhibitor), SQ22536 (an adenylate cyclase inhibitor), 8-Br-cAMP (membrane-permeable cAMP analog), ZD7288 (an hyperpolarization-activated cyclic nucleotide-gated channel blocker), chelerythrine (a PKC inhibitor), and KN-93 (a CaMKII inhibitor) while being sensitive to PKA inhibitors (H-89, KT5720, and Rp-cAMPS). Moreover, Xe inhibited evoked glycinergic transmission, which was canceled by KT5720. Like glycinergic transmission, spontaneous and evoked glutamatergic transmissions were also inhibited by Xe in a KT5720-sensitive manner. Our results suggest that Xe decreases glycinergic and glutamatergic spontaneous and evoked transmissions at the presynaptic level in a PKA-dependent manner. These presynaptic responses are independent of Ca2+ dynamics. We conclude that PKA can be the main molecular target of Xe in the inhibitory effects on both inhibitory and excitatory neurotransmitter release. SIGNIFICANCE STATEMENT: Spontaneous and evoked glycinergic and glutamatergic transmissions were investigated using the whole-cell patch clamp technique in rat spinal sacral dorsal commissural nucleus and hippocampal CA3 neurons, respectively. Xenon (Xe) significantly inhibited glycinergic and glutamatergic transmission presynaptically. As a signaling mechanism, protein kinase A was responsible for the inhibitory effects of Xe on both glycine and glutamate release. These results may help understand how Xe modulates neurotransmitter release and exerts its excellent anesthetic properties.
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Affiliation(s)
- Il-Sung Jang
- Kyungpook National University, Daegu, Republic of Korea (I.S.J., M.Na); Kumamoto Health Science University, Kumamoto, Japan (K.N.); Kyushu University, Fukuoka, Japan (M.No); Kitamoto Hospital, Saitama, Japan (N.K., N.A.); Fukuoka University, Fukuoka, Japan (S.K.); and Kumamoto Kinoh Hospital, Kumamoto, Japan (H.N., N.A.)
| | - Michiko Nakamura
- Kyungpook National University, Daegu, Republic of Korea (I.S.J., M.Na); Kumamoto Health Science University, Kumamoto, Japan (K.N.); Kyushu University, Fukuoka, Japan (M.No); Kitamoto Hospital, Saitama, Japan (N.K., N.A.); Fukuoka University, Fukuoka, Japan (S.K.); and Kumamoto Kinoh Hospital, Kumamoto, Japan (H.N., N.A.)
| | - Kiku Nonaka
- Kyungpook National University, Daegu, Republic of Korea (I.S.J., M.Na); Kumamoto Health Science University, Kumamoto, Japan (K.N.); Kyushu University, Fukuoka, Japan (M.No); Kitamoto Hospital, Saitama, Japan (N.K., N.A.); Fukuoka University, Fukuoka, Japan (S.K.); and Kumamoto Kinoh Hospital, Kumamoto, Japan (H.N., N.A.)
| | - Mami Noda
- Kyungpook National University, Daegu, Republic of Korea (I.S.J., M.Na); Kumamoto Health Science University, Kumamoto, Japan (K.N.); Kyushu University, Fukuoka, Japan (M.No); Kitamoto Hospital, Saitama, Japan (N.K., N.A.); Fukuoka University, Fukuoka, Japan (S.K.); and Kumamoto Kinoh Hospital, Kumamoto, Japan (H.N., N.A.)
| | - Naoki Kotani
- Kyungpook National University, Daegu, Republic of Korea (I.S.J., M.Na); Kumamoto Health Science University, Kumamoto, Japan (K.N.); Kyushu University, Fukuoka, Japan (M.No); Kitamoto Hospital, Saitama, Japan (N.K., N.A.); Fukuoka University, Fukuoka, Japan (S.K.); and Kumamoto Kinoh Hospital, Kumamoto, Japan (H.N., N.A.)
| | - Shutaro Katsurabayashi
- Kyungpook National University, Daegu, Republic of Korea (I.S.J., M.Na); Kumamoto Health Science University, Kumamoto, Japan (K.N.); Kyushu University, Fukuoka, Japan (M.No); Kitamoto Hospital, Saitama, Japan (N.K., N.A.); Fukuoka University, Fukuoka, Japan (S.K.); and Kumamoto Kinoh Hospital, Kumamoto, Japan (H.N., N.A.)
| | - Hideaki Nagami
- Kyungpook National University, Daegu, Republic of Korea (I.S.J., M.Na); Kumamoto Health Science University, Kumamoto, Japan (K.N.); Kyushu University, Fukuoka, Japan (M.No); Kitamoto Hospital, Saitama, Japan (N.K., N.A.); Fukuoka University, Fukuoka, Japan (S.K.); and Kumamoto Kinoh Hospital, Kumamoto, Japan (H.N., N.A.)
| | - Norio Akaike
- Kyungpook National University, Daegu, Republic of Korea (I.S.J., M.Na); Kumamoto Health Science University, Kumamoto, Japan (K.N.); Kyushu University, Fukuoka, Japan (M.No); Kitamoto Hospital, Saitama, Japan (N.K., N.A.); Fukuoka University, Fukuoka, Japan (S.K.); and Kumamoto Kinoh Hospital, Kumamoto, Japan (H.N., N.A.)
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4
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Böhm J, Scherzer S. Signaling and transport processes related to the carnivorous lifestyle of plants living on nutrient-poor soil. PLANT PHYSIOLOGY 2021; 187:2017-2031. [PMID: 35235668 PMCID: PMC8890503 DOI: 10.1093/plphys/kiab297] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 06/04/2021] [Indexed: 05/29/2023]
Abstract
In Eukaryotes, long-distance and rapid signal transmission is required in order to be able to react fast and flexibly to external stimuli. This long-distance signal transmission cannot take place by diffusion of signal molecules from the site of perception to the target tissue, as their speed is insufficient. Therefore, for adequate stimulus transmission, plants as well as animals make use of electrical signal transmission, as this can quickly cover long distances. This update summarises the most important advances in plant electrical signal transduction with a focus on the carnivorous Venus flytrap. It highlights the different types of electrical signals, examines their underlying ion fluxes and summarises the carnivorous processes downstream of the electrical signals.
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Affiliation(s)
- Jennifer Böhm
- Institute for Molecular Plant Physiology and Biophysics, University of Würzburg, 97082 Würzburg, Germany
| | - Sönke Scherzer
- Institute for Molecular Plant Physiology and Biophysics, University of Würzburg, 97082 Würzburg, Germany
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Spieth L, Berghoff SA, Stumpf SK, Winchenbach J, Michaelis T, Watanabe T, Gerndt N, Düking T, Hofer S, Ruhwedel T, Shaib AH, Willig K, Kronenberg K, Karst U, Frahm J, Rhee JS, Minguet S, Möbius W, Kruse N, von der Brelie C, Michels P, Stadelmann C, Hülper P, Saher G. Anesthesia triggers drug delivery to experimental glioma in mice by hijacking caveolar transport. Neurooncol Adv 2021; 3:vdab140. [PMID: 34647026 PMCID: PMC8500692 DOI: 10.1093/noajnl/vdab140] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Background Pharmaceutical intervention in the CNS is hampered by the shielding function of the blood–brain barrier (BBB). To induce clinical anesthesia, general anesthetics such as isoflurane readily penetrate the BBB. Here, we investigated whether isoflurane can be utilized for therapeutic drug delivery. Methods Barrier function in primary endothelial cells was evaluated by transepithelial/transendothelial electrical resistance, and nanoscale STED and SRRF microscopy. In mice, BBB permeability was quantified by extravasation of several fluorescent tracers. Mouse models including the GL261 glioma model were evaluated by MRI, immunohistochemistry, electron microscopy, western blot, and expression analysis. Results Isoflurane enhances BBB permeability in a time- and concentration-dependent manner. We demonstrate that, mechanistically, isoflurane disturbs the organization of membrane lipid nanodomains and triggers caveolar transport in brain endothelial cells. BBB tightness re-establishes directly after termination of anesthesia, providing a defined window for drug delivery. In a therapeutic glioblastoma trial in mice, simultaneous exposure to isoflurane and cytotoxic agent improves efficacy of chemotherapy. Conclusions Combination therapy, involving isoflurane-mediated BBB permeation with drug administration has far-reaching therapeutic implications for CNS malignancies.
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Affiliation(s)
- Lena Spieth
- Max-Planck-Institute of Experimental Medicine, Department of Neurogenetics, Göttingen, Germany
| | - Stefan A Berghoff
- Max-Planck-Institute of Experimental Medicine, Department of Neurogenetics, Göttingen, Germany
| | - Sina K Stumpf
- Max-Planck-Institute of Experimental Medicine, Department of Neurogenetics, Göttingen, Germany
| | - Jan Winchenbach
- Max-Planck-Institute of Experimental Medicine, Department of Neurogenetics, Göttingen, Germany
| | - Thomas Michaelis
- Max-Planck-Institut für biophysikalische Chemie, Biomedizinische NMR, Göttingen, Germany
| | - Takashi Watanabe
- Max-Planck-Institut für biophysikalische Chemie, Biomedizinische NMR, Göttingen, Germany
| | - Nina Gerndt
- Max-Planck-Institute of Experimental Medicine, Department of Neurogenetics, Göttingen, Germany
| | - Tim Düking
- Max-Planck-Institute of Experimental Medicine, Department of Neurogenetics, Göttingen, Germany
| | - Sabine Hofer
- Max-Planck-Institut für biophysikalische Chemie, Biomedizinische NMR, Göttingen, Germany
| | - Torben Ruhwedel
- Max-Planck-Institute of Experimental Medicine, Department of Neurogenetics, Göttingen, Germany.,Max-Planck-Institute of Experimental Medicine, Electron Microscopy Core Unit, Göttingen, Germany
| | - Ali H Shaib
- Max-Planck-Institute of Experimental Medicine, Department of Molecular Neurobiology, Göttingen, Germany
| | - Katrin Willig
- Max-Planck-Institute of Experimental Medicine, Group of Optical Nanoscopy in Neuroscience, Göttingen, Germany.,University Medical Center, Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), Göttingen, Germany
| | - Katharina Kronenberg
- Westfälische Wilhelms-Universität Münster, Institute of Inorganic and Analytical Chemistry, Münster, Germany
| | - Uwe Karst
- Westfälische Wilhelms-Universität Münster, Institute of Inorganic and Analytical Chemistry, Münster, Germany
| | - Jens Frahm
- Max-Planck-Institut für biophysikalische Chemie, Biomedizinische NMR, Göttingen, Germany
| | - Jeong Seop Rhee
- Max-Planck-Institute of Experimental Medicine, Department of Molecular Neurobiology, Göttingen, Germany
| | - Susana Minguet
- Albert-Ludwigs-University of Freiburg, Faculty of Biology, Freiburg, Germany. Signalling Research Centres BIOSS and CIBSS, Freiburg, Germany. Center of Chronic Immunodeficiency CCI, University Clinics and Medical Faculty, Freiburg, Germany
| | - Wiebke Möbius
- Max-Planck-Institute of Experimental Medicine, Department of Neurogenetics, Göttingen, Germany.,Max-Planck-Institute of Experimental Medicine, Electron Microscopy Core Unit, Göttingen, Germany.,University Medical Center, Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), Göttingen, Germany
| | - Niels Kruse
- University Medical Center Göttingen, Institute for Neuropathology, Göttingen, Germany
| | | | - Peter Michels
- University Medical Center Göttingen, Institute for Anesthesiology, Göttingen, Germany
| | - Christine Stadelmann
- University Medical Center Göttingen, Institute for Neuropathology, Göttingen, Germany
| | - Petra Hülper
- Klinikum Oldenburg, Oldenburg, University Hospital, Germany
| | - Gesine Saher
- Max-Planck-Institute of Experimental Medicine, Department of Neurogenetics, Göttingen, Germany
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Martins LF, Palace Carvalho AJ, Morgado P, Filipe EJ. Solubility of xenon in liquid n-alkanes and cycloalkanes by computer simulation. Towards the perfect anaesthetic. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.117272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Petrov E, Verkhovskiy A. Xenon as a transdermal enhancer for niacinamide in Strat-M™ membranes. Med Gas Res 2021; 12:24-27. [PMID: 34472499 PMCID: PMC8447954 DOI: 10.4103/2045-9912.320704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Xenon is confirmed to diffuse readily through membranes and has properties of transdermal enhancer. In this study, the ability of xenon to regulate the transdermal diffusion of niacinamide was investigated using a model of an artificial skin analogue of Strat-M™ membranes in Franz cells. Based on the data obtained, we found that in the simplified biophysical model of Strat-M™ membranes xenon exerts its enhancer effect based on the heterogeneous nucleation of xenon at the interfaces in the microporous structures of Strat-M™ membranes.
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Affiliation(s)
- Evgeny Petrov
- Laboratory of Biochemistry of Transport Systems, Faculty of Innovative Technologies, National Research Tomsk State University, Tomsk, Russian Federation
| | - Alexander Verkhovskiy
- Laboratory of Biochemistry of Transport Systems, Faculty of Innovative Technologies, National Research Tomsk State University, Tomsk, Russian Federation
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Towards Quantum-Chemical Modeling of the Activity of Anesthetic Compounds. Int J Mol Sci 2021; 22:ijms22179272. [PMID: 34502179 PMCID: PMC8431746 DOI: 10.3390/ijms22179272] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 08/16/2021] [Accepted: 08/17/2021] [Indexed: 12/16/2022] Open
Abstract
The modeling of the activity of anesthetics is a real challenge because of their unique electronic and structural characteristics. Microscopic approaches relevant to the typical features of these systems have been developed based on the advancements in the theory of intermolecular interactions. By stressing the quantum chemical point of view, here, we review the advances in the field highlighting differences and similarities among the chemicals within this group. The binding of the anesthetics to their partners has been analyzed by Symmetry-Adapted Perturbation Theory to provide insight into the nature of the interaction and the modeling of the adducts/complexes allows us to rationalize their anesthetic properties. A new approach in the frame of microtubule concept and the importance of lipid rafts and channels in membranes is also discussed.
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Baluška F, Yokawa K. Anaesthetics and plants: from sensory systems to cognition-based adaptive behaviour. PROTOPLASMA 2021; 258:449-454. [PMID: 33462719 PMCID: PMC7907011 DOI: 10.1007/s00709-020-01594-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Accepted: 11/25/2020] [Indexed: 05/02/2023]
Abstract
Plants are not only sensitive to exogenous anaesthetics, but they also produce multitudes of endogenous substances, especially when stressed, that often have anaesthetic and anelgesic properties when applied to both humans and animals. Moreover, plants rely on neurotransmitters and their receptors for cell-cell communication and integration in a similar fashion to the use of neural systems in animals and humans. Plants also use their plant-specific sensory systems and neurotransmitter-based communication, including long-distance action potentials, to manage stress via cognition-like plant-specific behaviour and adaptation.
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Affiliation(s)
| | - Ken Yokawa
- Faculty of Engineering, Kitami Institute of Technology, Hokkaido, 090-8597, Japan.
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10
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Interaction of drugs with lipid raft membrane domains as a possible target. Drug Target Insights 2021; 14:34-47. [PMID: 33510571 PMCID: PMC7832984 DOI: 10.33393/dti.2020.2185] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 11/11/2020] [Indexed: 01/23/2023] Open
Abstract
Introduction Plasma membranes are not the homogeneous bilayers of uniformly distributed lipids but the lipid complex with laterally separated lipid raft membrane domains, which provide receptor, ion channel and enzyme proteins with a platform. The aim of this article is to review the mechanistic interaction of drugs with membrane lipid rafts and address the question whether drugs induce physicochemical changes in raft-constituting and raft-surrounding membranes. Methods Literature searches of PubMed/MEDLINE and Google Scholar databases from 2000 to 2020 were conducted to include articles published in English in internationally recognized journals. Collected articles were independently reviewed by title, abstract and text for relevance. Results The literature search indicated that pharmacologically diverse drugs interact with raft model membranes and cellular membrane lipid rafts. They could physicochemically modify functional protein-localizing membrane lipid rafts and the membranes surrounding such domains, affecting the raft organizational integrity with the resultant exhibition of pharmacological activity. Raft-acting drugs were characterized as ones to decrease membrane fluidity, induce liquid-ordered phase or order plasma membranes, leading to lipid raft formation; and ones to increase membrane fluidity, induce liquid-disordered phase or reduce phase transition temperature, leading to lipid raft disruption. Conclusion Targeting lipid raft membrane domains would open a new way for drug design and development. Since angiotensin-converting enzyme 2 receptors which are a cell-specific target of and responsible for the cellular entry of novel coronavirus are localized in lipid rafts, agents that specifically disrupt the relevant rafts may be a drug against coronavirus disease 2019.
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Reyes-Figueroa AD, Karttunen M, Ruiz-Suárez JC. Cholesterol sequestration by xenon nano bubbles leads to lipid raft destabilization. SOFT MATTER 2020; 16:9655-9661. [PMID: 33078812 DOI: 10.1039/d0sm01256d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Combined coarse-grained (CG) and atomistic molecular dynamics (MD) simulations were performed to study the interactions of xenon with model lipid rafts consisting of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC), 1,2-dilauroyl-sn-glycero-3-phosphocholine (DLPC) and cholesterol (Chol). At a concentration of 2 Xe/lipid we observed an unexpected result: spontaneous nucleation of Xe nano bubbles which rapidly plunged into the bilayer. In this process Chol, essential for raft stabilization, was pulled out from the raft into the hydrophobic zone. When concentration was further increased (3 Xe/lipid), the bubbles increase in size and disrupted both the membrane and raft. We computed the radial distribution functions, pair-wise potentials, second virial coefficients and Schlitter entropy to scrutinize the nature of the interactions. Our findings, concurring with a recent report on the origin of general anaesthesia (M. A. Pavel, E. N. Petersen, H. Wang, R. A. Lerner and S. B. Hansen, Proc. Natl. Acad. Sci. U. S. A., 2020, 117(24), 13757-13766), suggest that the well-known anaesthetic effect of Xe could be mediated by sequestration of Chol, which, in turn, compromises the stability of rafts where specialized proteins needed to produce the nervous signal are anchored.
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Zapata-Morin PA, Sierra-Valdez FJ, Ruiz-Suárez JC. The cut-off effect of n-alcohols in lipid rafts: A lipid-dependent phenomenon ☆. J Mol Graph Model 2020; 101:107732. [PMID: 32920240 DOI: 10.1016/j.jmgm.2020.107732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 08/25/2020] [Accepted: 08/26/2020] [Indexed: 10/23/2022]
Abstract
n-Aliphatic alcohols act as anesthetics only up to a certain chain length, beyond which its biological activity disappears. This is known as the 'cut-off' phenomenon. Although the most accepted explanation is based on action sites in membrane proteins, it is not well understood why alcohols alter their functions. The structural dependence of these protein receptors to lipid domains known as 'lipid rafts', suggests a new approach to tackle the puzzling phenomenon. In this work, by performing molecular dynamic simulations (MDS) to explore the lipid role, we provide relevant molecular details about the membrane-alcohol interaction at the cut-off point regime. Since the high variability of the cut-off points found on protein receptors in neurons may be a consequence of differences in the lipid composition surrounding such proteins, our results could have a clear-cut importance.
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Affiliation(s)
- Patricio A Zapata-Morin
- Facultad de Ciencias Biológicas, Laboratorio de Micología y Fitopatología, Universidad Autónoma de Nuevo León, San Nicolás de Los Garza, Nuevo León, 66455, Mexico
| | - F J Sierra-Valdez
- Centro de Investigación Biomédica, Hospital Zambrano Hellion, TecSalud, Ave. Batallón de San Patricio 112, San Pedro Garza García, 66278, Nuevo León, Mexico; Tecnológico de Monterrey, Escuela de Ingeniería y Ciencias, Ave. Eugenio Garza Sada 2501 Sur, Monterrey, Nuevo León, 64849, Mexico
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Petersen EN, Pavel MA, Wang H, Hansen SB. Disruption of palmitate-mediated localization; a shared pathway of force and anesthetic activation of TREK-1 channels. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2020; 1862:183091. [PMID: 31672538 PMCID: PMC6907892 DOI: 10.1016/j.bbamem.2019.183091] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 09/15/2019] [Accepted: 09/17/2019] [Indexed: 12/22/2022]
Abstract
TWIK related K+ channel (TREK-1) is a mechano- and anesthetic sensitive channel that when activated attenuates pain and causes anesthesia. Recently the enzyme phospholipase D2 (PLD2) was shown to bind to the channel and generate a local high concentration of phosphatidic acid (PA), an anionic signaling lipid that gates TREK-1. In a biological membrane, the cell harnesses lipid heterogeneity (lipid compartments) to control gating of TREK-1 using palmitate-mediated localization of PLD2. Here we discuss the ability of mechanical force and anesthetics to disrupt palmitate-mediated localization of PLD2 giving rise to TREK-1's mechano- and anesthetic-sensitive properties. The likely consequences of this indirect lipid-based mechanism of activation are discussed in terms of a putative model for excitatory and inhibitory mechano-effectors and anesthetic sensitive ion channels in a biological context. Lastly, we discuss the ability of locally generated PA to reach mM concentrations near TREK-1 and the biophysics of localized signaling. Palmitate-mediated localization of PLD2 emerges as a central control mechanism of TREK-1 responding to mechanical force and anesthetic action. This article is part of a Special Issue entitled: Molecular biophysics of membranes and membrane proteins.
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Affiliation(s)
- E Nicholas Petersen
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL 33458, USA; Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458, USA
| | - Mahmud Arif Pavel
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL 33458, USA; Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458, USA
| | - Hao Wang
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL 33458, USA; Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458, USA
| | - Scott B Hansen
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL 33458, USA; Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458, USA.
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14
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Comert F, Greenwood A, Maramba J, Acevedo R, Lucas L, Kulasinghe T, Cairns LS, Wen Y, Fu R, Hammer J, Blazyk J, Sukharev S, Cotten ML, Mihailescu M. The host-defense peptide piscidin P1 reorganizes lipid domains in membranes and decreases activation energies in mechanosensitive ion channels. J Biol Chem 2019; 294:18557-18570. [PMID: 31619519 PMCID: PMC6901303 DOI: 10.1074/jbc.ra119.010232] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Revised: 10/01/2019] [Indexed: 11/06/2022] Open
Abstract
The host-defense peptide (HDP) piscidin 1 (P1), isolated from the mast cells of striped bass, has potent activities against bacteria, viruses, fungi, and cancer cells and can also modulate the activity of membrane receptors. Given its broad pharmacological potential, here we used several approaches to better understand its interactions with multicomponent bilayers representing models of bacterial (phosphatidylethanolamine (PE)/phosphatidylglycerol) and mammalian (phosphatidylcholine/cholesterol (PC/Chol)) membranes. Using solid-state NMR, we solved the structure of P1 bound to PC/Chol and compared it with that of P3, a less potent homolog. The comparison disclosed that although both peptides are interfacially bound and α-helical, they differ in bilayer orientations and depths of insertion, and these differences depend on bilayer composition. Although Chol is thought to make mammalian membranes less susceptible to HDP-mediated destabilization, we found that Chol does not affect the permeabilization effects of P1. X-ray diffraction experiments revealed that both piscidins produce a demixing effect in PC/Chol membranes by increasing the fraction of the Chol-depleted phase. Furthermore, P1 increased the temperature required for the lamellar-to-hexagonal phase transition in PE bilayers, suggesting that it imposes positive membrane curvature. Patch-clamp measurements on the inner Escherichia coli membrane showed that P1 and P3, at concentrations sufficient for antimicrobial activity, substantially decrease the activating tension for bacterial mechanosensitive channels. This indicated that piscidins can cause lipid redistribution and restructuring in the microenvironment near proteins. We conclude that the mechanism of piscidin's antimicrobial activity extends beyond simple membrane destabilization, helping to rationalize its broader spectrum of pharmacological effects.
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Affiliation(s)
- Fatih Comert
- Institute for Bioscience and Biotechnology Research, Rockville, Maryland 20850
| | - Alexander Greenwood
- Department of Applied Science, William and Mary, Williamsburg, Virginia 23185
| | - Joseph Maramba
- Biology Department, University of Maryland, College Park, Maryland 20742
| | - Roderico Acevedo
- Institute for Bioscience and Biotechnology Research, Rockville, Maryland 20850
| | - Laura Lucas
- Institute for Bioscience and Biotechnology Research, Rockville, Maryland 20850
| | - Thulasi Kulasinghe
- Institute for Bioscience and Biotechnology Research, Rockville, Maryland 20850
| | - Leah S Cairns
- Department of Biochemistry and Molecular Biology, The Johns Hopkins University, Baltimore, Maryland 21205
| | - Yi Wen
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York 14853
| | - Riqiang Fu
- National High Magnetic Field Laboratory, Tallahassee, Florida 32310
| | - Janet Hammer
- Department of Biomedical Sciences, Ohio University, Athens, Ohio 45701
| | - Jack Blazyk
- Department of Biomedical Sciences, Ohio University, Athens, Ohio 45701
| | - Sergei Sukharev
- Biology Department, University of Maryland, College Park, Maryland 20742
| | - Myriam L Cotten
- Department of Applied Science, William and Mary, Williamsburg, Virginia 23185.
| | - Mihaela Mihailescu
- Institute for Bioscience and Biotechnology Research, Rockville, Maryland 20850.
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15
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Hishida M, Yanagisawa R, Yamamura Y, Saito K. Phase separation of a ternary lipid vesicle including n-alkane: Rugged vesicle and bilayer flakes formed by separation between highly rigid and flexible domains. J Chem Phys 2019; 150:064904. [PMID: 30769992 DOI: 10.1063/1.5080177] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
We investigate the phase separation of a ternary lipid bilayer including n-alkane and construct the ternary phase diagram. When a certain proportion of a long n-alkane is mixed with a binary mixture of lipids, which exhibit the disordered liquid-crystalline phase and the ordered gel phase at room temperature, we observed the characteristic morphology of bilayers with phase separation. The ordered bilayer forms flat and rigid domains, which is connected or rimmed with flexible domains in the disordered phase. The asymmetric emergence of the phase separation region close to the ordered phase side is interpreted based on the almost equal distribution of the n-alkane to the ordered and disordered phase domains.
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Affiliation(s)
- Mafumi Hishida
- Department of Chemistry, Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8571, Japan
| | - Ryuta Yanagisawa
- Department of Chemistry, Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8571, Japan
| | - Yasuhisa Yamamura
- Department of Chemistry, Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8571, Japan
| | - Kazuya Saito
- Department of Chemistry, Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8571, Japan
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16
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Baluška F, Reber A. Sentience and Consciousness in Single Cells: How the First Minds Emerged in Unicellular Species. Bioessays 2019; 41:e1800229. [PMID: 30714631 DOI: 10.1002/bies.201800229] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Revised: 12/06/2018] [Indexed: 12/13/2022]
Abstract
A reductionistic, bottom-up, cellular-based concept of the origins of sentience and consciousness has been put forward. Because all life is based on cells, any evolutionary theory of the emergence of sentience and consciousness must be grounded in mechanisms that take place in prokaryotes, the simplest unicellular species. It has been posited that subjective awareness is a fundamental property of cellular life. It emerges as an inherent feature of, and contemporaneously with, the very first life-forms. All other varieties of mentation are the result of evolutionary mechanisms based on this singular event. Therefore, all forms of sentience and consciousness evolve from this original instantiation in prokaryotes. It has also been identified that three cellular structures and mechanisms that likely play critical roles here are excitable membranes, oscillating cytoskeletal polymers, and structurally flexible proteins. Finally, basic biophysical principles are proposed to guide those processes that underly the emergence of supracellular sentience from cellular sentience in multicellular organisms.
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Affiliation(s)
- František Baluška
- Institute of Cellular and Molecular Botany, University of Bonn, 53115 Bonn, Germany
| | - Arthur Reber
- Department of Psychology, University of British Columbia, Vancouver, Canada
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17
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Baluška F, Mancuso S. Actin Cytoskeleton and Action Potentials: Forgotten Connections. THE CYTOSKELETON 2019. [DOI: 10.1007/978-3-030-33528-1_5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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18
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Weinrich M, Worcester DL. The actions of volatile anesthetics: a new perspective. Acta Crystallogr D Struct Biol 2018; 74:1169-1177. [PMID: 30605131 PMCID: PMC6317591 DOI: 10.1107/s2059798318004771] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Accepted: 03/22/2018] [Indexed: 11/10/2022] Open
Abstract
This article reviews recent work in applying neutron and X-ray scattering towards the elucidation of the molecular mechanisms of volatile anesthetics. Experimental results on domain mixing in ternary lipid mixtures, and the influence of volatile anesthetics and hydrostatic pressure are placed in the contexts of ion-channel function and receptor trafficking at the postsynaptic density.
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19
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Petrov E, Menon G, Rohde PR, Battle AR, Martinac B, Solioz M. Xenon-inhibition of the MscL mechano-sensitive channel and the CopB copper ATPase under different conditions suggests direct effects on these proteins. PLoS One 2018; 13:e0198110. [PMID: 29864148 PMCID: PMC5986136 DOI: 10.1371/journal.pone.0198110] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Accepted: 05/14/2018] [Indexed: 11/18/2022] Open
Abstract
Xenon is frequently used as a general anesthetic in humans, but the mechanism remains an issue of debate. While for some membrane proteins, a direct interaction of xenon with the protein has been shown to be the inhibitory mechanism, other membrane protein functions could be affected by changes of membrane properties due to partitioning of the gas into the lipid bilayer. Here, the effect of xenon on a mechanosensitive ion channel and a copper ion-translocating ATPase was compared under different conditions. Xenon inhibited spontaneous gating of the Escherichia coli mechano-sensitive mutant channel MscL-G22E, as shown by patch-clamp recording techniques. Under high hydrostatic pressure, MscL-inhibition was reversed. Similarly, the activity of the Enterococcus hirae CopB copper ATPase, reconstituted into proteoliposomes, was inhibited by xenon. However, the CopB ATPase activity was also inhibited by xenon when CopB was in a solubilized state. These findings suggest that xenon acts by directly interacting with these proteins, rather than via indirect effects by altering membrane properties. Also, inhibition of copper transport may be a novel effect of xenon that contributes to anesthesia.
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Affiliation(s)
- Evgeny Petrov
- Laboratory of Biochemistry and Molecular Biology, Tomsk State University, Tomsk, Russia
| | - Gopalakrishnan Menon
- Laboratory of Biochemistry and Molecular Biology, Tomsk State University, Tomsk, Russia
| | - Paul R Rohde
- Victor Chang Cardiac Research Institute, Darlinghurst, Australia
| | - Andrew R Battle
- Victor Chang Cardiac Research Institute, Darlinghurst, Australia.,School of Biomedical Sciences, Queensland University of Technology (QUT), Brisbane, Australia
| | - Boris Martinac
- Victor Chang Cardiac Research Institute, Darlinghurst, Australia.,St Vincent's Clinical School, University of New South Wales, Darlinghurst, Australia
| | - Marc Solioz
- Laboratory of Biochemistry and Molecular Biology, Tomsk State University, Tomsk, Russia.,Department Clinical Research, University of Bern, Bern, Switzerland
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20
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Roose BW, Zemerov SD, Dmochowski IJ. Xenon-Protein Interactions: Characterization by X-Ray Crystallography and Hyper-CEST NMR. Methods Enzymol 2018; 602:249-272. [PMID: 29588032 DOI: 10.1016/bs.mie.2018.02.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The physiological activity of xenon has long been recognized, though the exact nature of its interactions with biomolecules remains poorly understood. Xe is an inert noble gas, but can act as a general anesthetic, most likely by binding internal hydrophobic cavities within proteins. Understanding Xe-protein interactions, therefore, can provide crucial insight regarding the mechanism of Xe anesthesia and potentially other general anesthetic agents. Historically, Xe-protein interactions have been studied primarily through X-ray crystallography and nuclear magnetic resonance (NMR). In this chapter, we first describe our methods for preparing Xe derivatives of protein crystals and identifying Xe-binding sites. Second, we detail our procedure for 129Xe hyper-CEST NMR spectroscopy, a versatile NMR technique well suited for characterizing the weak, transient nature of Xe-protein interactions.
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21
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Banerjee D, Simon CM, Elsaidi SK, Haranczyk M, Thallapally PK. Xenon Gas Separation and Storage Using Metal-Organic Frameworks. Chem 2018. [DOI: 10.1016/j.chempr.2017.12.025] [Citation(s) in RCA: 96] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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22
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Vallverdú J, Castro O, Mayne R, Talanov M, Levin M, Baluška F, Gunji Y, Dussutour A, Zenil H, Adamatzky A. Slime mould: The fundamental mechanisms of biological cognition. Biosystems 2018; 165:57-70. [DOI: 10.1016/j.biosystems.2017.12.011] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Revised: 12/18/2017] [Accepted: 12/20/2017] [Indexed: 01/27/2023]
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23
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Borsacchi S, Geppi M, Macchi S, Ninham BW, Fratini E, Ambrosi M, Baglioni P, Lo Nostro P. Phase transitions in hydrophobe/phospholipid mixtures: hints at connections between pheromones and anaesthetic activity. Phys Chem Chem Phys 2018; 18:15375-83. [PMID: 27210443 DOI: 10.1039/c6cp00659k] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The phase behavior of a mixture of a typical insect pheromone (olean) and a phospholipid (DOPC)/water dispersion is extensively explored through SAXS, NMR and DSC experiments. The results mimic those obtained with anaesthetics in phospholipid/water systems. They also mimic the behavior and microstructure of ternary mixtures of a membrane mimetic, bilayer-forming double chained surfactants, oils and water. Taken together with recent models for conduction of the nervous impulse, all hint at lipid involvement and the underlying unity in mechanisms of pheromone, anaesthetic and hydrophobic drugs, where a local phase change in the lipid membrane architecture may be at least partly involved in the transmission of the signal.
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Affiliation(s)
- Silvia Borsacchi
- Istituto di Chimica dei Composti OrganoMetallici (ICCOM) del CNR, 56124 Pisa, Italy
| | - Marco Geppi
- Department of Chemistry and Industrial Chemistry, University of Pisa, 56124 Pisa, Italy
| | - Sara Macchi
- Department of Chemistry and Industrial Chemistry, University of Pisa, 56124 Pisa, Italy
| | - Barry W Ninham
- Department of Chemistry & CSGI, University of Florence, 50019 Sesto Fiorentino (Firenze), Italy. and Department of Applied Mathematics, Research School of Physical Sciences and Engineering, Australian National University, Canberra, ACT 0200, Australia
| | - Emiliano Fratini
- Department of Chemistry & CSGI, University of Florence, 50019 Sesto Fiorentino (Firenze), Italy.
| | - Moira Ambrosi
- Department of Chemistry & CSGI, University of Florence, 50019 Sesto Fiorentino (Firenze), Italy.
| | - Piero Baglioni
- Department of Chemistry & CSGI, University of Florence, 50019 Sesto Fiorentino (Firenze), Italy. and Enzo Ferroni Foundation, 50019 Sesto Fiorentino (Firenze), Italy
| | - Pierandrea Lo Nostro
- Department of Chemistry & CSGI, University of Florence, 50019 Sesto Fiorentino (Firenze), Italy. and Enzo Ferroni Foundation, 50019 Sesto Fiorentino (Firenze), Italy
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24
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Weinrich M, Worcester DL, Bezrukov SM. Lipid nanodomains change ion channel function. NANOSCALE 2017; 9:13291-13297. [PMID: 28858358 PMCID: PMC5599369 DOI: 10.1039/c7nr03926c] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Signaling proteins and neurotransmitter receptors often associate with saturated chain and cholesterol-rich domains of cell membranes, also known as lipid rafts. The saturated chains and high cholesterol environment in lipid rafts can modulate protein function, but evidence for such modulation of ion channel function in lipid rafts is lacking. Here, using raft-forming model membrane systems containing cholesterol, we show that lipid lateral phase separation at the nanoscale level directly affects the dissociation kinetics of the gramicidin dimer, a model ion channel.
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Affiliation(s)
- Michael Weinrich
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA.
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25
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Ninham BW, Larsson K, Lo Nostro P. Two sides of the coin. Part 2. Colloid and surface science meets real biointerfaces. Colloids Surf B Biointerfaces 2017; 159:394-404. [PMID: 28822288 DOI: 10.1016/j.colsurfb.2017.07.090] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Revised: 06/07/2017] [Accepted: 07/31/2017] [Indexed: 12/23/2022]
Abstract
Part 1 revisited developments in lipid and surfactant self assembly over the past 40 years [1]. New concepts emerged. Here we explore how these developments can be used to make sense of and bring order to a range of complex biological phenomena. Together with Part 1, this contribution is a fundamental revision of intuition at the boundaries of Colloid Science and Biological interfaces from a perspective of nearly 50 years. We offer new insights on a unified treatment of self assembly of lipids, surfactants and proteins in the light of developments presented in Part 1. These were in the enabling disciplines in molecular forces, hydration, oil and electrolyte specificity; and in the role of non Euclidean geometries-across the whole gammut of physical, colloid and surface chemistry, biophysics and membrane biology and medicine. It is where the early founders of the cell theory of biology and the physiologists expected advances to occur as D'Arcy Thompson predicted us 100 years ago.
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Affiliation(s)
- Barry W Ninham
- Department of Applied Mathematics, Research School of Physical Sciences and Engineering, Australian National University, Canberra, ACT 0200, Australia; Department of Chemistry "Ugo Schiff", University of Florence, 50019 Sesto Fiorentino, Firenze, Italy
| | - Kåre Larsson
- Camurus Lipid Research Foundation, Ideon Science Park, 22370 Lund, Sweden
| | - Pierandrea Lo Nostro
- Department of Chemistry "Ugo Schiff", University of Florence, 50019 Sesto Fiorentino, Firenze, Italy; Fondazione Prof. Enzo Ferroni-Onlus, 50019 Sesto Fiorentino, Firenze, Italy.
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26
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Lemoine S, Blanchart K, Souplis M, Lemaitre A, Legallois D, Coulbault L, Simard C, Allouche S, Abraini JH, Hanouz JL, Rouet R, Sallé L, Guinamard R, Manrique A. Argon Exposure Induces Postconditioning in Myocardial Ischemia-Reperfusion. J Cardiovasc Pharmacol Ther 2017; 22:564-573. [PMID: 28381122 DOI: 10.1177/1074248417702891] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BACKGROUND AND PURPOSE Cardioprotection against ischemia-reperfusion (I/R) damages remains a major concern during prehospital management of acute myocardial infarction. Noble gases have shown beneficial effects in preconditioning studies. Because emergency proceedings in the context of myocardial infarction require postconditioning strategies, we evaluated the effects of argon in such protocols on mammalian cardiac tissue. EXPERIMENTAL APPROACHES In rat, cardiac I/R was induced in vivo by transient coronary artery ligature and cardiac functions were evaluated by magnetic resonance imaging. Hypoxia-reoxygenation (H/R)-induced arrhythmias were evaluated in vitro using intracellular microelectrodes on both rat-isolated ventricle and a model of border zone in guinea pig ventricle. Hypoxia-reoxygenation loss of contractile force was assessed in human atrial appendages. In those models, postconditioning was induced by 5 minutes application of argon at the time of reperfusion. KEY RESULTS In the in vivo model, I/R produced left ventricular ejection fraction decrease (24%) and wall motion score increase (36%) which was prevented when argon was applied in postconditioning. In vitro, argon postconditioning abolished H/R-induced arrhythmias such as early after depolarizations, conduction blocks, and reentries. Recovery of contractile force in human atrial appendages after H/R was enhanced in the argon group, increasing from 51% ± 2% in the nonconditioned group to 83% ± 7% in the argon-treated group ( P < .001). This effect of argon was abolished in the presence of wortmannin and PD98059 which inhibit prosurvival phosphatidylinositol-3-kinase (PI3K)/protein kinase B (Akt) and MEK/extracellular receptor kinase 1/2 (ERK 1/2), respectively, or in the presence of the mitochondrial permeability transition pore opener atractyloside, suggesting the involvement of the reperfusion injury salvage kinase pathway. CONCLUSION AND IMPLICATIONS Argon has strong cardioprotective properties when applied in conditions of postconditioning and thus appears as a potential therapeutic tool in I/R situations.
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Affiliation(s)
- Sandrine Lemoine
- 1 Signalisation, Electrophysiologie et Imagerie des lésions d'ischémie-reperfusion myocardique, Normandie Univ, UNICAEN, Caen, France
| | - Katrien Blanchart
- 1 Signalisation, Electrophysiologie et Imagerie des lésions d'ischémie-reperfusion myocardique, Normandie Univ, UNICAEN, Caen, France
| | - Mathieu Souplis
- 1 Signalisation, Electrophysiologie et Imagerie des lésions d'ischémie-reperfusion myocardique, Normandie Univ, UNICAEN, Caen, France
| | - Adrien Lemaitre
- 1 Signalisation, Electrophysiologie et Imagerie des lésions d'ischémie-reperfusion myocardique, Normandie Univ, UNICAEN, Caen, France
| | - Damien Legallois
- 1 Signalisation, Electrophysiologie et Imagerie des lésions d'ischémie-reperfusion myocardique, Normandie Univ, UNICAEN, Caen, France
| | - Laurent Coulbault
- 1 Signalisation, Electrophysiologie et Imagerie des lésions d'ischémie-reperfusion myocardique, Normandie Univ, UNICAEN, Caen, France
| | - Christophe Simard
- 1 Signalisation, Electrophysiologie et Imagerie des lésions d'ischémie-reperfusion myocardique, Normandie Univ, UNICAEN, Caen, France
| | - Stéphane Allouche
- 1 Signalisation, Electrophysiologie et Imagerie des lésions d'ischémie-reperfusion myocardique, Normandie Univ, UNICAEN, Caen, France
| | - Jacques H Abraini
- 1 Signalisation, Electrophysiologie et Imagerie des lésions d'ischémie-reperfusion myocardique, Normandie Univ, UNICAEN, Caen, France
| | - Jean-Luc Hanouz
- 1 Signalisation, Electrophysiologie et Imagerie des lésions d'ischémie-reperfusion myocardique, Normandie Univ, UNICAEN, Caen, France
| | - René Rouet
- 1 Signalisation, Electrophysiologie et Imagerie des lésions d'ischémie-reperfusion myocardique, Normandie Univ, UNICAEN, Caen, France
| | - Laurent Sallé
- 1 Signalisation, Electrophysiologie et Imagerie des lésions d'ischémie-reperfusion myocardique, Normandie Univ, UNICAEN, Caen, France
| | - Romain Guinamard
- 1 Signalisation, Electrophysiologie et Imagerie des lésions d'ischémie-reperfusion myocardique, Normandie Univ, UNICAEN, Caen, France
| | - Alain Manrique
- 1 Signalisation, Electrophysiologie et Imagerie des lésions d'ischémie-reperfusion myocardique, Normandie Univ, UNICAEN, Caen, France
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27
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Reigada R. Alteration of interleaflet coupling due to compounds displaying rapid translocation in lipid membranes. Sci Rep 2016; 6:32934. [PMID: 27596355 PMCID: PMC5011781 DOI: 10.1038/srep32934] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Accepted: 08/17/2016] [Indexed: 12/02/2022] Open
Abstract
The spatial coincidence of lipid domains at both layers of the cell membrane is expected to play an important role in many cellular functions. Competition between the surface interleaflet tension and a line hydrophobic mismatch penalty are conjectured to determine the transversal behavior of laterally heterogeneous lipid membranes. Here, by a combination of molecular dynamics simulations, a continuum field theory and kinetic equations, I demonstrate that the presence of small, rapidly translocating molecules residing in the lipid bilayer may alter its transversal behavior by favoring the spatial coincidence of similar lipid phases.
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Affiliation(s)
- Ramon Reigada
- Department de Química Física and Institut de Química Teòrica i Computacional (IQTCUB), Universitat de Barcelona, c/ Martí i Franqués 1, Pta 4, 08028 Barcelona Spain
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28
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Calcium and protons affect the interaction of neurotransmitters and anesthetics with anionic lipid membranes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2016; 1858:2215-2222. [DOI: 10.1016/j.bbamem.2016.06.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Revised: 06/16/2016] [Accepted: 06/22/2016] [Indexed: 01/09/2023]
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29
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Sierra-Valdez FJ, Ruiz-Suárez JC, Delint-Ramirez I. Pentobarbital modifies the lipid raft-protein interaction: A first clue about the anesthesia mechanism on NMDA and GABA A receptors. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2016; 1858:2603-2610. [PMID: 27457704 DOI: 10.1016/j.bbamem.2016.07.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Revised: 07/19/2016] [Accepted: 07/21/2016] [Indexed: 12/13/2022]
Abstract
Recent studies have shown that anesthetic agents alter the physical properties of lipid rafts on model membranes. However, if this destabilization occurs in brain membranes, altering the lipid raft-protein interaction, remains unknown. We analyzed the effects produced by pentobarbital (PB) on brain plasma membranes and lipid rafts in vivo. We characterized for the first time the thermotropic behavior of plasma membranes, synaptosomes, and lipid rafts from rat brain. We found that the transition temperature from the ordered gel to disordered liquid phase of lipids is close to physiological temperature. We then studied the effect of PB on protein composition of lipid rafts. Our results show a reduction of the total protein associated to rafts, with a higher reduction of the NMDAR compared to the GABAA receptor. Both receptors are considered the main targets of PB. In general, our results suggest that lipid rafts could be plausible mediators in anesthetic action.
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Affiliation(s)
| | - J C Ruiz-Suárez
- Cinvestav-Monterrey, PIIT, Apodaca, Nuevo León, 66600, Mexico
| | - Ilse Delint-Ramirez
- Departamento de Farmacología y Toxicología, Facultad de Medicina, Universidad Autónoma de Nuevo León, Monterrey, Mexico; Centro de Investigación y Desarrollo en Ciencias de la Salud, Universidad Autónoma de Nuevo León, Monterrey, Mexico.
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30
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Exploring the Effects on Lipid Bilayer Induced by Noble Gases via Molecular Dynamics Simulations. Sci Rep 2015; 5:17235. [PMID: 26601882 PMCID: PMC4658558 DOI: 10.1038/srep17235] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Accepted: 10/27/2015] [Indexed: 12/30/2022] Open
Abstract
Noble gases seem to have no significant effect on the anesthetic targets due to their simple, spherical shape. However, xenon has strong narcotic efficacy and can be used clinically, while other noble gases cannot. The mechanism remains unclear. Here, we performed molecular dynamics simulations on phospholipid bilayers with four kinds of noble gases to elucidate the difference of their effects on the membrane. Our results showed that the sequence of effects on membrane exerted by noble gases from weak to strong was Ne, Ar, Kr and Xe, the same order as their relative narcotic potencies as well as their lipid/water partition percentages. Compared with the other three kinds of noble gases, more xenon molecules were distributed between the lipid tails and headgroups, resulting in membrane’s lateral expansion and lipid tail disorder. It may contribute to xenon’s strong anesthetic potency. The results are well consistent with the membrane mediated mechanism of general anesthesia.
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Worcester DL, Weinrich M. Hydrostatic Pressure Promotes Domain Formation in Model Lipid Raft Membranes. J Phys Chem Lett 2015; 6:4417-4421. [PMID: 26538052 DOI: 10.1021/acs.jpclett.5b02134] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Neutron diffraction measurements demonstrate that hydrostatic pressure promotes liquid-ordered (Lo) domain formation in lipid membranes prepared as both oriented multilayers and unilamellar vesicles made of a canonical ternary lipid mixture for which demixing transitions have been extensively studied. The results demonstrate an unusually large dependence of the mixing transition on hydrostatic pressure. Additionally, data at 28 °C show that the magnitude of increase in Lo caused by 10 MPa pressure is much the same as the decrease in Lo produced by twice minimum alveolar concentrations (MAC) of general anesthetics such as halothane, nitrous oxide, and xenon. Therefore, the results may provide a plausible explanation for the reversal of general anesthesia by hydrostatic pressure.
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Affiliation(s)
- David L Worcester
- NIST Center for Neutron Research, National Institute of Standards and Technology , Gaithersburg 20899, Maryland, United States
- Department of Physiology and Biophysics, University of California , Irvine 92697, California, United States
| | - Michael Weinrich
- NIST Center for Neutron Research, National Institute of Standards and Technology , Gaithersburg 20899, Maryland, United States
- Eunice Kennedy Shriver National Center of Child Health and Human Development, National Institutes of Health , 31 Center Drive, Bethesda 20892, Maryland, United States
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Effects of neurosteroids on a model membrane including cholesterol: A micropipette aspiration study. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2015; 1848:1268-76. [PMID: 25660752 DOI: 10.1016/j.bbamem.2015.01.017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2014] [Revised: 01/14/2015] [Accepted: 01/23/2015] [Indexed: 11/21/2022]
Abstract
Amphiphilic molecules supposed to affect membrane protein activity could strongly interact also with the lipid component of the membrane itself. Neurosteroids are amphiphilic molecules that bind to plasma membrane receptors of cells in the central nervous system but their effect on membrane is still under debate. For this reason it is interesting to investigate their effects on pure lipid bilayers as model systems. Using the micropipette aspiration technique (MAT), here we studied the effects of a neurosteroid, allopregnanolone (3α,5α-tetrahydroprogesterone or Allo) and of one of its isoforms, isoallopregnanolone (3β,5α-tetrahydroprogesterone or isoAllo), on the physical properties of pure lipid bilayers composed by DOPC/bSM/chol. Allo is a well-known positive allosteric modulator of GABAA receptor activity while isoAllo acts as a non-competitive functional antagonist of Allo modulation. We found that Allo, when applied at nanomolar concentrations (50-200 nM) to a lipid bilayer model system including cholesterol, induces an increase of the lipid bilayer area and a decrease of the mechanical parameters. Conversely, isoAllo, decreases the lipid bilayer area and, when applied, at the same nanomolar concentrations, it does not affect significantly its mechanical parameters. We characterized the kinetics of Allo uptake by the lipid bilayer and we also discussed its aspects in relation to the slow kinetics of Allo gating effects on GABAA receptors. The overall results presented here show that a correlation exists between the modulation of Allo and isoAllo of GABAA receptor activity and their effects on a lipid bilayer model system containing cholesterol.
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Sacchi M, Balleza D, Vena G, Puia G, Facci P, Alessandrini A. Effect of neurosteroids on a model lipid bilayer including cholesterol: An Atomic Force Microscopy study. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2015; 1848:1258-67. [PMID: 25620773 DOI: 10.1016/j.bbamem.2015.01.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2014] [Revised: 12/18/2014] [Accepted: 01/02/2015] [Indexed: 12/20/2022]
Abstract
Amphiphilic molecules which have a biological effect on specific membrane proteins, could also affect lipid bilayer properties possibly resulting in a modulation of the overall membrane behavior. In light of this consideration, it is important to study the possible effects of amphiphilic molecule of pharmacological interest on model systems which recapitulate some of the main properties of the biological plasma membranes. In this work we studied the effect of a neurosteroid, Allopregnanolone (3α,5α-tetrahydroprogesterone or Allo), on a model bilayer composed by the ternary lipid mixture DOPC/bSM/chol. We chose ternary mixtures which present, at room temperature, a phase coexistence of liquid ordered (Lo) and liquid disordered (Ld) domains and which reside near to a critical point. We found that Allo, which is able to strongly partition in the lipid bilayer, induces a marked increase in the bilayer area and modifies the relative proportion of the two phases favoring the Ld phase. We also found that the neurosteroid shifts the miscibility temperature to higher values in a way similarly to what happens when the cholesterol concentration is decreased. Interestingly, an isoform of Allo, isoAllopregnanolone (3β,5α-tetrahydroprogesterone or isoAllo), known to inhibit the effects of Allo on GABAA receptors, has an opposite effect on the bilayer properties.
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Affiliation(s)
- Mattia Sacchi
- Dipartimento di Scienze Fisiche, Matematiche e Informatiche, Via Campi 213/A, 41125 Modena, Italy; CNR - Istituto Nanoscienze, S3, Via Campi 213/A, 41125 Modena, Italy
| | - Daniel Balleza
- CNR - Istituto Nanoscienze, S3, Via Campi 213/A, 41125 Modena, Italy
| | - Giulia Vena
- Dipartimento di Scienze della Vita, Università di Modena e Reggio Emilia, Via Campi 287, Modena 287, Italy
| | - Giulia Puia
- Dipartimento di Scienze della Vita, Università di Modena e Reggio Emilia, Via Campi 287, Modena 287, Italy
| | - Paolo Facci
- CNR - Istituto di Biofisica, Via De Marini 6, 16149 Genova, Italy
| | - Andrea Alessandrini
- Dipartimento di Scienze Fisiche, Matematiche e Informatiche, Via Campi 213/A, 41125 Modena, Italy; CNR - Istituto Nanoscienze, S3, Via Campi 213/A, 41125 Modena, Italy.
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Yoshida K, Takashima A, Nishio I. Effect of dibucaine hydrochloride on raft-like lipid domains in model membrane systems. MEDCHEMCOMM 2015. [DOI: 10.1039/c5md00108k] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
To clarify the biophysical and/or physicochemical mechanism of anaesthesia, we investigated the influence of dibucaine hydrochloride (DC·HCl), a local anaesthetic, on raft-like domains in ternary liposomes composed of dioleoylphosphatidylcholine (DOPC), dipalmitoylphosphatidylcholine (DPPC) and cholesterol (Chol).
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Affiliation(s)
- Kazunari Yoshida
- New Industry Creation Hatchery Center
- Tohoku University
- 6-6-10 Aoba
- Aoba-ku
- Japan
| | - Akito Takashima
- Department of Physics and Mathematics
- College of Science and Engineering
- Aoyama Gakuin University
- 5-10-1 Fuchinobe
- Sagamihara
| | - Izumi Nishio
- Department of Physics and Mathematics
- College of Science and Engineering
- Aoyama Gakuin University
- 5-10-1 Fuchinobe
- Sagamihara
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Andrijchenko NN, Ermilov AY, Khriachtchev L, Räsänen M, Nemukhin AV. Toward molecular mechanism of xenon anesthesia: a link to studies of xenon complexes with small aromatic molecules. J Phys Chem A 2014; 119:2517-21. [PMID: 25285819 DOI: 10.1021/jp508800k] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The present study illustrates the steps toward understanding molecular mechanism of xenon anesthesia by focusing on a link to the structures and spectra of intermolecular complexes of xenon with small aromatic molecules. A primary cause of xenon anesthesia is attributed to inhibition of N-methyl-D-aspartate (NMDA) receptors by an unknown mechanism. Following the results of quantum mechanics/molecular mechanics (QM/MM) and molecular dynamics (MD) calculations we report plausible xenon action sites in the ligand binding domain of the NMDA receptor, which are due to interaction of xenon atoms with aromatic amino-acid residues. We rely in these calculations on computational protocols adjusted in combined experimental and theoretical studies of intermolecular complexes of xenon with phenol. Successful reproduction of vibrational shifts in molecular species upon complexation with xenon measured in low-temperature matrices allowed us to select a proper functional form in density functional theory (DFT) approach for use in QM subsystems, as well as to calibrate force field parameters for MD simulations. The results of molecular modeling show that xenon atoms can compete with agonists for a place in the corresponding protein cavity, thus indicating their active role in anesthetic action.
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Affiliation(s)
- Natalya N Andrijchenko
- †Department of Chemistry, M. V. Lomonosov Moscow State University, Leninskie Gory 1/3, Moscow 119991, Russian Federation
| | - Alexander Yu Ermilov
- †Department of Chemistry, M. V. Lomonosov Moscow State University, Leninskie Gory 1/3, Moscow 119991, Russian Federation
| | - Leonid Khriachtchev
- ‡Department of Chemistry, University of Helsinki, P.O. Box 55, Helsinki FI-00014, Finland
| | - Markku Räsänen
- ‡Department of Chemistry, University of Helsinki, P.O. Box 55, Helsinki FI-00014, Finland
| | - Alexander V Nemukhin
- †Department of Chemistry, M. V. Lomonosov Moscow State University, Leninskie Gory 1/3, Moscow 119991, Russian Federation.,§N. M. Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, Kosygina 4, Moscow 119334, Russian Federation
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Barnoud J, Rossi G, Marrink SJ, Monticelli L. Hydrophobic compounds reshape membrane domains. PLoS Comput Biol 2014; 10:e1003873. [PMID: 25299598 PMCID: PMC4191877 DOI: 10.1371/journal.pcbi.1003873] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Accepted: 07/25/2014] [Indexed: 12/12/2022] Open
Abstract
Cell membranes have a complex lateral organization featuring domains with distinct composition, also known as rafts, which play an essential role in cellular processes such as signal transduction and protein trafficking. In vivo, perturbations of membrane domains (e.g., by drugs or lipophilic compounds) have major effects on the activity of raft-associated proteins and on signaling pathways, but they are difficult to characterize because of the small size of the domains, typically below optical resolution. Model membranes, instead, can show macroscopic phase separation between liquid-ordered and liquid-disordered domains, and they are often used to investigate the driving forces of membrane lateral organization. Studies in model membranes have shown that some lipophilic compounds perturb membrane domains, but it is not clear which chemical and physical properties determine domain perturbation. The mechanisms of domain stabilization and destabilization are also unknown. Here we describe the effect of six simple hydrophobic compounds on the lateral organization of phase-separated model membranes consisting of saturated and unsaturated phospholipids and cholesterol. Using molecular simulations, we identify two groups of molecules with distinct behavior: aliphatic compounds promote lipid mixing by distributing at the interface between liquid-ordered and liquid-disordered domains; aromatic compounds, instead, stabilize phase separation by partitioning into liquid-disordered domains and excluding cholesterol from the disordered domains. We predict that relatively small concentrations of hydrophobic species can have a broad impact on domain stability in model systems, which suggests possible mechanisms of action for hydrophobic compounds in vivo.
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Affiliation(s)
- Jonathan Barnoud
- IBCP, CNRS UMR 5086, Lyon, France
- Université Claude Bernard Lyon I, Lyon, France
| | - Giulia Rossi
- Dept of Physics, University of Genoa, Genoa, Italy
| | - Siewert J. Marrink
- Groningen Biomolecular Sciences and Biotechnology Institute and Zernike Institute for Advanced Materials, University of Groningen, Groningen, The Netherlands
| | - Luca Monticelli
- IBCP, CNRS UMR 5086, Lyon, France
- Université Claude Bernard Lyon I, Lyon, France
- * E-mail:
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