1
|
Sharma A, Kumar V, Chakraborty S. Micro-Solvation of Propofol in Propylene Glycol-Water Binary Mixtures: Molecular Dynamics Simulation Studies. J Phys Chem B 2023; 127:11011-11022. [PMID: 37972382 DOI: 10.1021/acs.jpcb.3c04932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2023]
Abstract
The water microstructure around propofol plays a crucial role in controlling their solubility in the binary mixture. The unusual nature of such a water microstructure can influence both translational and reorientational dynamics, as well as the water hydrogen bond network near propofol. We have carried out all-atom molecular dynamics simulations of five different compositions of the propylene glycol (PG)/water binary mixture containing propofol (PFL) molecules to investigate the differential behavior of water microsolvation shells around propofol, which is likely to control the propofol solubility. It is evident from the simulation snapshots for various compositions that the PG at high molecular ratio favors the water cluster and extended chainlike network that percolates within the PG matrix, where the propofol is in the dispersed state. We estimated that the radial distribution function indicates higher ordered water microstructure around propofol for high PG content, as compared to the lower PG content in the PG/water mixture. So, the hydrophilic PG regulates the stability of the water micronetwork around propofol and its solubility in the binary mixture. We observed that the translational and rotational mobility of water belonging to the propofol microsolvation shell is hindered for high PG content and relaxed toward the low PG molecular ratio in the PG/water mixture. It has been noticed that the structural relaxation of the hydrogen bond formed between the propofol and the water molecules present in the propofol microsolvation shell for all five compositions is found to be slower for high PG content and becomes faster on the way to low PG content in the mixture. Simultaneously, we calculated the intermittent residence time correlation function of the water molecules belonging to the microsolvation shell around the propofol for five different compositions and found a faster short time decay followed up with long time components. Again, the origin of such long time decay is primarily from the structural relaxation of the microsolvation shell around the propofol, where the high PG content shows the slower structural relaxation that turns faster as the PG content approaches to the other end of the compositions. So, our studies showed that the slower structural relaxation of the microsolvation shell around propofol for a high PG molecular ratio in the PG/water mixture correlate well with the extensive ordering of the water microstructure and restricted water mobility and facilitates the dissolution process of propofol in the binary mixture.
Collapse
Affiliation(s)
- Anupama Sharma
- Department of Computational Sciences, School of Basic Sciences, Central University of Punjab, Bathinda 151401, India
| | - Vishal Kumar
- Department of Computational Sciences, School of Basic Sciences, Central University of Punjab, Bathinda 151401, India
| | - Sudip Chakraborty
- Department of Computational Sciences, School of Basic Sciences, Central University of Punjab, Bathinda 151401, India
| |
Collapse
|
2
|
Nguyen TQT, Lund FW, Zanjani AAH, Khandelia H. Magic mushroom extracts in lipid membranes. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2022; 1864:183957. [PMID: 35561790 DOI: 10.1016/j.bbamem.2022.183957] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 04/28/2022] [Accepted: 05/02/2022] [Indexed: 06/15/2023]
Abstract
The active hallucinogen of magic mushrooms, psilocin, is being repurposed to treat nicotine addiction and treatment-resistant depression. Psilocin belongs to the tryptamine class of psychedelic compounds which include the hormone serotonin. It is believed that psilocin exerts its effect by binding to the serotonin 5-HT2A receptor. However, recent in-vivo evidence suggests that psilocin may employ a different mechanism to exert its effects. Membrane-mediated receptor desensitization of neurotransmitter receptors is one such mechanism. We compare the impact of the neutral and charged versions of psilocin and serotonin on the properties of zwitterionic and anionic lipid membranes using molecular dynamics simulations and calorimetry. Both compounds partition to the lipid interface and induce membrane thinning. The tertiary amine in psilocin, as opposed to the primary amine in serotonin, limits psilocin's impact on the membrane although more psilocin partitions into the membrane than serotonin. Calorimetry corroborates that both compounds induce a classical melting point depression like anesthetics do. Our results also lend support to a membrane-mediated receptor-binding mechanism for both psilocin and serotonin and provide physical insights into subtle chemical changes that can alter the membrane-binding of psychedelic compounds.
Collapse
Affiliation(s)
- Teresa Quynh Tram Nguyen
- Physical Life Science, Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Frederik Wendelboe Lund
- Physical Life Science, Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Ali Asghar Hakami Zanjani
- Physical Life Science, Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark.
| | - Himanshu Khandelia
- Physical Life Science, Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark.
| |
Collapse
|
3
|
Róg T, Girych M, Bunker A. Mechanistic Understanding from Molecular Dynamics in Pharmaceutical Research 2: Lipid Membrane in Drug Design. Pharmaceuticals (Basel) 2021; 14:1062. [PMID: 34681286 PMCID: PMC8537670 DOI: 10.3390/ph14101062] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Revised: 10/14/2021] [Accepted: 10/15/2021] [Indexed: 11/17/2022] Open
Abstract
We review the use of molecular dynamics (MD) simulation as a drug design tool in the context of the role that the lipid membrane can play in drug action, i.e., the interaction between candidate drug molecules and lipid membranes. In the standard "lock and key" paradigm, only the interaction between the drug and a specific active site of a specific protein is considered; the environment in which the drug acts is, from a biophysical perspective, far more complex than this. The possible mechanisms though which a drug can be designed to tinker with physiological processes are significantly broader than merely fitting to a single active site of a single protein. In this paper, we focus on the role of the lipid membrane, arguably the most important element outside the proteins themselves, as a case study. We discuss work that has been carried out, using MD simulation, concerning the transfection of drugs through membranes that act as biological barriers in the path of the drugs, the behavior of drug molecules within membranes, how their collective behavior can affect the structure and properties of the membrane and, finally, the role lipid membranes, to which the vast majority of drug target proteins are associated, can play in mediating the interaction between drug and target protein. This review paper is the second in a two-part series covering MD simulation as a tool in pharmaceutical research; both are designed as pedagogical review papers aimed at both pharmaceutical scientists interested in exploring how the tool of MD simulation can be applied to their research and computational scientists interested in exploring the possibility of a pharmaceutical context for their research.
Collapse
Affiliation(s)
- Tomasz Róg
- Department of Physics, University of Helsinki, 00014 Helsinki, Finland;
| | - Mykhailo Girych
- Department of Physics, University of Helsinki, 00014 Helsinki, Finland;
| | - Alex Bunker
- Drug Research Program, Division of Pharmaceutical Biosciences, Faculty of Pharmacy, University of Helsinki, 00014 Helsinki, Finland;
| |
Collapse
|
4
|
Cetuk H, Anishkin A, Scott AJ, Rempe SB, Ernst RK, Sukharev S. Partitioning of Seven Different Classes of Antibiotics into LPS Monolayers Supports Three Different Permeation Mechanisms through the Outer Bacterial Membrane. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:1372-1385. [PMID: 33449700 DOI: 10.1021/acs.langmuir.0c02652] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The outer membrane (OM) of Gram-negative (G-) bacteria presents a barrier for many classes of antibacterial agents. Lipopolysaccharide (LPS), present in the outer leaflet of the OM, is stabilized by divalent cations and is considered to be the major impediment for antibacterial agent permeation. However, the actual affinities of major antibiotic classes toward LPS have not yet been determined. In the present work, we use Langmuir monolayers formed from E. coli Re and Rd types of LPS to record pressure-area isotherms in the presence of antimicrobial agents. Our observations suggest three general types of interactions. First, some antimicrobials demonstrated no measurable interactions with LPS. This lack of interaction in the case of cefsulodin, a third-generation cephalosporin antibiotic, correlates with its low efficacy against G- bacteria. Ampicillin and ciprofloxacin also show no interactions with LPS, but in contrast to cefsulodin, both exhibit good efficacy against G- bacteria, indicating permeation through common porins. Second, we observe substantial intercalation of the more hydrophobic antibiotics, novobiocin, rifampicin, azithromycin, and telithromycin, into relaxed LPS monolayers. These largely repartition back to the subphase with monolayer compression. We find that the hydrophobic area, charge, and dipole all show correlations with both the mole fraction of antibiotic retained in the monolayer at the monolayer-bilayer equivalence pressure and the efficacies of these antibiotics against G- bacteria. Third, amine-rich gentamicin and the cationic antimicrobial peptides polymyxin B and colistin show no hydrophobic insertion but are instead strongly driven into the polar LPS layer by electrostatic interactions in a pressure-independent manner. Their intercalation stably increases the area per molecule (by up to 20%), which indicates massive formation of defects in the LPS layer. These defects support a self-promoted permeation mechanism of these antibiotics through the OM, which explains the high efficacy and specificity of these antimicrobials against G- bacteria.
Collapse
Affiliation(s)
- Hannah Cetuk
- Biology Department, University of Maryland, College Park, Maryland 20742, United States
| | - Andriy Anishkin
- Biology Department, University of Maryland, College Park, Maryland 20742, United States
| | - Alison J Scott
- Department of Microbial Pathogenesis, University of Maryland, Baltimore, Baltimore Maryland 21201, United States
| | - Susan B Rempe
- Center for Chemical, Biological, Radiation, and Nuclear Defense and Energy Technology, Sandia National Laboratories, Albuquerque, New Mexico 87185, United States
| | - Robert K Ernst
- Department of Microbial Pathogenesis, University of Maryland, Baltimore, Baltimore Maryland 21201, United States
| | - Sergei Sukharev
- Biology Department, University of Maryland, College Park, Maryland 20742, United States
| |
Collapse
|
5
|
Alet AI, Batista da Silva MV, Castellini HV, Alet NA, Riquelme BD. In vitro alteration on erythrocytes mechanical properties by propofol, remifentanil and vecuronium. Microvasc Res 2021; 135:104132. [PMID: 33421433 DOI: 10.1016/j.mvr.2021.104132] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Revised: 12/30/2020] [Accepted: 12/31/2020] [Indexed: 11/18/2022]
Abstract
Several studies report flow disturbance and microcirculation disorders upon anesthesia treatment. These alterations are often related to blood rheology changes. In this work, it was attempted to make a detailed description of the alterations in erythrocyte mechanical properties by the action of propofol, remifentanil, and vecuronium. For this, an in vitro study was performed on red blood cell samples from healthy donors incubated with solutions of propofol (4 μg/mL whole blood), remifentanil (10 ng/mL plasma), and vecuronium (0.15 μg/mL plasma). Erythrocyte viscoelastic parameters were determined by octuplicate using a Reómetro Eritrocitario. Also, a Wilcoxon signed rank-test with Yates correction for continuity was performed to analyze the overall alteration in the mechanical properties of erythrocytes. Statistical analysis showed that the three studied anesthetics changed the erythrocyte mechanical properties at different parts of the membrane. These results would imply an interaction of these anesthetics with the erythrocyte membrane. Finally, this could conduce to alterations in microcirculation.
Collapse
Affiliation(s)
- Analía I Alet
- Facultad Cs. Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 535, 2000 Rosario, Argentina.
| | - Marcus V Batista da Silva
- Facultad Cs. Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 535, 2000 Rosario, Argentina.
| | - Horacio V Castellini
- Facultad Cs. Exactas Ingeniería y Agrimensura, Universidad Nacional de Rosario, Pellegrini 250, 2000 Rosario, Argentina.
| | - Nicolás A Alet
- Facultad Cs. Médicas, Universidad Nacional de Rosario, Santa Fe 3100, 2000 Rosario, Hospital Provincial del Centenario. Urquiza 3101, 2000 Rosario, Argentina.
| | - Bibiana D Riquelme
- Facultad Cs. Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 535, 2000 Rosario, Argentina; Grupo de Física Biomédica, IFIR (CONICET-UNR), Bv. 27 de febrero 210 bis, 2000 Rosario, Argentina.
| |
Collapse
|
6
|
Effects of gabergic phenols on the dynamic and structure of lipid bilayers: A molecular dynamic simulation approach. PLoS One 2019; 14:e0218042. [PMID: 31237897 PMCID: PMC6592534 DOI: 10.1371/journal.pone.0218042] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Accepted: 05/24/2019] [Indexed: 11/19/2022] Open
Abstract
γ-Aminobutyric acid (GABA) is the major inhibitory neurotransmitter in the vertebrate and invertebrate nervous system. GABAA receptors are activated by GABA and their agonists, and modulated by a wide variety of recognized drugs, including barbiturates, anesthetics, and benzodiazepines. The phenols propofol, thymol, chlorothymol, carvacrol and eugenol act as positive allosteric modulators on GABAA-R receptor. These GABAergic phenols interact with the lipid membrane, therefore, their anesthetic activity could be the combined result of their specific activity (with receptor proteins) as well as nonspecific interactions (with surrounding lipid molecules) modulating the supramolecular organization of the receptor environment. Therefore, we aimed to contribute to a description of the molecular events that occur at the membrane level as part of the mechanism of general anesthesia, using a molecular dynamic simulation approach. Equilibrium molecular dynamics simulations indicate that the presence of GABAergic phenols in a DPPC bilayer orders lipid acyl chains for carbons near the interface and their effect is not significant at the bilayer center. Phenols interacts with the polar interface of phospholipid bilayer, particularly forming hydrogen bonds with the glycerol and phosphate group. Also, potential of mean force calculations using umbrella sampling show that propofol partition is mainly enthalpic driven at the polar region and entropic driven at the hydrocarbon chains. Finally, potential of mean force indicates that propofol partition into a gel DPPC phase is not favorable. Our in silico results were positively contrasted with previous experimental data.
Collapse
|
7
|
Enkavi G, Javanainen M, Kulig W, Róg T, Vattulainen I. Multiscale Simulations of Biological Membranes: The Challenge To Understand Biological Phenomena in a Living Substance. Chem Rev 2019; 119:5607-5774. [PMID: 30859819 PMCID: PMC6727218 DOI: 10.1021/acs.chemrev.8b00538] [Citation(s) in RCA: 175] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Indexed: 12/23/2022]
Abstract
Biological membranes are tricky to investigate. They are complex in terms of molecular composition and structure, functional over a wide range of time scales, and characterized by nonequilibrium conditions. Because of all of these features, simulations are a great technique to study biomembrane behavior. A significant part of the functional processes in biological membranes takes place at the molecular level; thus computer simulations are the method of choice to explore how their properties emerge from specific molecular features and how the interplay among the numerous molecules gives rise to function over spatial and time scales larger than the molecular ones. In this review, we focus on this broad theme. We discuss the current state-of-the-art of biomembrane simulations that, until now, have largely focused on a rather narrow picture of the complexity of the membranes. Given this, we also discuss the challenges that we should unravel in the foreseeable future. Numerous features such as the actin-cytoskeleton network, the glycocalyx network, and nonequilibrium transport under ATP-driven conditions have so far received very little attention; however, the potential of simulations to solve them would be exceptionally high. A major milestone for this research would be that one day we could say that computer simulations genuinely research biological membranes, not just lipid bilayers.
Collapse
Affiliation(s)
- Giray Enkavi
- Department
of Physics, University of
Helsinki, P.O. Box 64, FI-00014 Helsinki, Finland
| | - Matti Javanainen
- Department
of Physics, University of
Helsinki, P.O. Box 64, FI-00014 Helsinki, Finland
- Institute
of Organic Chemistry and Biochemistry of the Czech Academy
of Sciences, Flemingovo naḿesti 542/2, 16610 Prague, Czech Republic
- Computational
Physics Laboratory, Tampere University, P.O. Box 692, FI-33014 Tampere, Finland
| | - Waldemar Kulig
- Department
of Physics, University of
Helsinki, P.O. Box 64, FI-00014 Helsinki, Finland
| | - Tomasz Róg
- Department
of Physics, University of
Helsinki, P.O. Box 64, FI-00014 Helsinki, Finland
- Computational
Physics Laboratory, Tampere University, P.O. Box 692, FI-33014 Tampere, Finland
| | - Ilpo Vattulainen
- Department
of Physics, University of
Helsinki, P.O. Box 64, FI-00014 Helsinki, Finland
- Computational
Physics Laboratory, Tampere University, P.O. Box 692, FI-33014 Tampere, Finland
- MEMPHYS-Center
for Biomembrane Physics
| |
Collapse
|
8
|
Oakes V, Domene C. Capturing the Molecular Mechanism of Anesthetic Action by Simulation Methods. Chem Rev 2018; 119:5998-6014. [DOI: 10.1021/acs.chemrev.8b00366] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Victoria Oakes
- Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, United Kingdom
| | - Carmen Domene
- Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, United Kingdom
- Department of Chemistry, University of Oxford, Oxford OX1 3TA, United Kingdom
| |
Collapse
|
9
|
Niga P, Hansson-Mille PM, Swerin A, Claesson PM, Schoelkopf J, Gane PAC, Bergendal E, Tummino A, Campbell RA, Magnus Johnson C. Interactions between model cell membranes and the neuroactive drug propofol. J Colloid Interface Sci 2018; 526:230-243. [PMID: 29734090 DOI: 10.1016/j.jcis.2018.03.052] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Revised: 03/12/2018] [Accepted: 03/14/2018] [Indexed: 12/13/2022]
Abstract
Vibrational sum frequency spectroscopy (VSFS) complemented by surface pressure isotherm and neutron reflectometry (NR) experiments were employed to investigate the interactions between propofol, a small amphiphilic molecule that currently is the most common general anaesthetic drug, and phospholipid monolayers. A series of biologically relevant saturated phospholipids of varying chain length from C18 to C14 were spread on either pure water or propofol (2,6-bis(1-methylethyl)phenol) solution in a Langmuir trough, and the change in the molecular structure of the film, induced by the interaction with propofol, was studied with respect to the surface pressure. The results from the surface pressure isotherm experiments revealed that propofol, as long as it remains at the interface, enhances the fluidity of the phospholipid monolayer. The VSF spectra demonstrate that for each phospholipid the amount of propofol in the monolayer region decreases with increasing surface pressure. Such squeeze out is in contrast to the enhanced interactions that can be exhibited by more complex amphiphilic molecules such as peptides. At surface pressures of 22-25 mN m-1, which are relevant for biological cell membranes, most of the propofol has been expelled from the monolayer, especially in the case of the C16 and C18 phospholipids that adopt a liquid condensed phase packing of its alkyl tails. At lower surface pressures of 5 mN m-1, the effect of propofol on the structure of the alkyl tails is enhanced when the phospholipids are present in a liquid expanded phase. Specifically, for the C16 phospholipid, NR data reveal that propofol is located exclusively in the head group region, which is rationalized in the context of previous studies. The results imply a non-homogeneous distribution of propofol in the plane of real cell membranes, which is an inference that requires urgent testing and may help to explain why such low concentration of the drug are required to induce general anaesthesia.
Collapse
Affiliation(s)
- Petru Niga
- RISE - Research Institute of Sweden, Bioscience and Materials - Surface, Process and Formulation Box 5607, SE-114 28 Stockholm, Sweden.
| | - Petra M Hansson-Mille
- RISE - Research Institute of Sweden, Bioscience and Materials - Surface, Process and Formulation Box 5607, SE-114 28 Stockholm, Sweden
| | - Agne Swerin
- RISE - Research Institute of Sweden, Bioscience and Materials - Surface, Process and Formulation Box 5607, SE-114 28 Stockholm, Sweden; KTH Royal Institute of Technology, Department of Chemistry, Division of Surface and Corrosion Science, SE-100 44 Stockholm, Sweden
| | - Per M Claesson
- RISE - Research Institute of Sweden, Bioscience and Materials - Surface, Process and Formulation Box 5607, SE-114 28 Stockholm, Sweden; KTH Royal Institute of Technology, Department of Chemistry, Division of Surface and Corrosion Science, SE-100 44 Stockholm, Sweden
| | | | - Patrick A C Gane
- Omya International AG, Baslerstrasse 42, CH-4665 Oftringen, Switzerland; Aalto University, School of Chemical Engineering, Department of Bioproducts and Biosystems, P.O. Box 16300, FI-00076 Aalto, Helsinki, Finland
| | - Erik Bergendal
- KTH Royal Institute of Technology, Department of Chemistry, Division of Surface and Corrosion Science, SE-100 44 Stockholm, Sweden
| | - Andrea Tummino
- Institut Laue-Langevin, 71 avenue des Martyrs, 38042 Grenoble, France; Eötvös Loránd University, Budapest 112, P.O. Box 32, H-1518, Hungary
| | | | - C Magnus Johnson
- KTH Royal Institute of Technology, Department of Chemistry, Division of Surface and Corrosion Science, SE-100 44 Stockholm, Sweden.
| |
Collapse
|
10
|
Nuriya M, Yasui D, Yamada T, Aoki T, Yasui M. Direct posttranslational modification of astrocytic connexin 43 proteins by the general anesthetic propofol in the cerebral cortex. Biochem Biophys Res Commun 2018; 497:734-741. [DOI: 10.1016/j.bbrc.2018.02.142] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Accepted: 02/16/2018] [Indexed: 10/18/2022]
|
11
|
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]
|
12
|
From hopanoids to cholesterol: Molecular clocks of pentameric ligand-gated ion channels. Prog Lipid Res 2016; 63:1-13. [DOI: 10.1016/j.plipres.2016.03.003] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2015] [Revised: 03/22/2016] [Accepted: 03/24/2016] [Indexed: 11/21/2022]
|
13
|
Mariani ME, Sánchez-Borzone ME, García DA. Effects of bioactive monoterpenic ketones on membrane organization. A langmuir film study. Chem Phys Lipids 2016; 198:39-45. [DOI: 10.1016/j.chemphyslip.2016.05.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Revised: 04/13/2016] [Accepted: 05/03/2016] [Indexed: 10/21/2022]
|
14
|
Postila PA, Vattulainen I, Róg T. Selective effect of cell membrane on synaptic neurotransmission. Sci Rep 2016; 6:19345. [PMID: 26782980 PMCID: PMC4725992 DOI: 10.1038/srep19345] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Accepted: 12/07/2015] [Indexed: 12/25/2022] Open
Abstract
Atomistic molecular dynamics simulations were performed with 13 non-peptidic neurotransmitters (NTs) in three different membrane environments. The results provide compelling evidence that NTs are divided into membrane-binding and membrane-nonbinding molecules. NTs adhere to the postsynaptic membrane surface whenever the ligand-binding sites of their synaptic receptors are buried in the lipid bilayer. In contrast, NTs that have extracellular ligand-binding sites do not have a similar tendency to adhere to the membrane surface. This finding is a seemingly simple yet important addition to the paradigm of neurotransmission, essentially dividing it into membrane-independent and membrane-dependent mechanisms. Moreover, the simulations also indicate that the lipid composition especially in terms of charged lipids can affect the membrane partitioning of NTs. The revised paradigm, highlighting the importance of cell membrane and specific lipids for neurotransmission, should to be of interest to neuroscientists, drug industry and the general public alike.
Collapse
Affiliation(s)
- Pekka A. Postila
- Department of Physics, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere, Finland
- Department of Chemistry and Biochemistry, University of California San Diego, 92093-0340 San Diego, CA, USA
| | - Ilpo Vattulainen
- Department of Physics, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere, Finland
- MEMPHYS– Center for Biomembrane Physics, University of Southern Denmark, Odense, Denmark
- Department of Physics, University of Helsinki, P.O. Box 64, FI-00014, Helsinki, Finland
| | - Tomasz Róg
- Department of Physics, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere, Finland
| |
Collapse
|
15
|
Membrane Affinity of Platensimycin and Its Dialkylamine Analogs. Int J Mol Sci 2015; 16:17909-32. [PMID: 26247942 PMCID: PMC4581228 DOI: 10.3390/ijms160817909] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Revised: 07/22/2015] [Accepted: 07/24/2015] [Indexed: 12/13/2022] Open
Abstract
Membrane permeability is a desired property in drug design, but there have been difficulties in quantifying the direct drug partitioning into native membranes. Platensimycin (PL) is a new promising antibiotic whose biosynthetic production is costly. Six dialkylamine analogs of PL were synthesized with identical pharmacophores but different side chains; five of them were found inactive. To address the possibility that their activity is limited by the permeation step, we calculated polarity, measured surface activity and the ability to insert into the phospholipid monolayers. The partitioning of PL and the analogs into the cytoplasmic membrane of E. coli was assessed by activation curve shifts of a re-engineered mechanosensitive channel, MscS, in patch-clamp experiments. Despite predicted differences in polarity, the affinities to lipid monolayers and native membranes were comparable for most of the analogs. For PL and the di-myrtenyl analog QD-11, both carrying bulky sidechains, the affinity for the native membrane was lower than for monolayers (half-membranes), signifying that intercalation must overcome the lateral pressure of the bilayer. We conclude that the biological activity among the studied PL analogs is unlikely to be limited by their membrane permeability. We also discuss the capacity of endogenous tension-activated channels to detect asymmetric partitioning of exogenous substances into the native bacterial membrane and the different contributions to the thermodynamic force which drives permeation.
Collapse
|
16
|
Alsop RJ, Armstrong CL, Maqbool A, Toppozini L, Dies H, Rheinstädter MC. Cholesterol expels ibuprofen from the hydrophobic membrane core and stabilizes lamellar phases in lipid membranes containing ibuprofen. SOFT MATTER 2015; 11:4756-4767. [PMID: 25915907 DOI: 10.1039/c5sm00597c] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
There is increasing evidence that common drugs, such as aspirin and ibuprofen, interact with lipid membranes. Ibuprofen is one of the most common over the counter drugs in the world, and is used for relief of pain and fever. It interacts with the cyclooxygenase pathway leading to inhibition of prostaglandin synthesis. From X-ray diffraction of highly oriented model membranes containing between 0 and 20 mol% ibuprofen, 20 mol% cholesterol, and dimyristoylphosphatidylcholine (DMPC), we present evidence for a non-specific interaction between ibuprofen and cholesterol in lipid bilayers. At a low ibuprofen concentrations of 2 mol%, three different populations of ibuprofen molecules were found: two in the lipid head group region and one in the hydrophobic membrane core. At higher ibuprofen concentrations of 10 and 20 mol%, the lamellar bilayer structure is disrupted and a lamellar to cubic phase transition was observed. In the presence of 20 mol% cholesterol, ibuprofen (at 5 mol%) was found to be expelled from the membrane core and reside solely in the head group region of the bilayers. 20 mol% cholesterol was found to stabilize lamellar membrane structure and the formation of a cubic phase at 10 and 20 mol% ibuprofen was suppressed. The results demonstrate that ibuprofen interacts with lipid membranes and that the interaction is strongly dependent on the presence of cholesterol.
Collapse
Affiliation(s)
- Richard J Alsop
- Department of Physics and Astronomy, McMaster University, ABB-241, 1280 Main Street West, Hamilton, Ontario L8S 4M1, Canada.
| | | | | | | | | | | |
Collapse
|
17
|
Macroscopic and macromolecular specificity of alkylphenol anesthetics for neuronal substrates. Sci Rep 2015; 5:9695. [PMID: 25853337 PMCID: PMC4894431 DOI: 10.1038/srep09695] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2014] [Accepted: 02/24/2015] [Indexed: 01/06/2023] Open
Abstract
We used a photoactive general anesthetic called meta-azi-propofol (AziPm) to test the selectivity and specificity of alkylphenol anesthetic binding in mammalian brain. Photolabeling of rat brain sections with [3H]AziPm revealed widespread but heterogeneous ligand distribution, with [3H]AziPm preferentially binding to synapse-dense areas compared to areas composed largely of cell bodies or myelin. With [3H]AziPm and propofol, we determined that alkylphenol general anesthetics bind selectively and specifically to multiple synaptic protein targets. In contrast, the alkylphenol anesthetics do not bind to specific sites on abundant phospholipids or cholesterol, although [3H]AziPm shows selectivity for photolabeling phosphatidylethanolamines. Together, our experiments suggest that alkylphenol anesthetic substrates are widespread in number and distribution, similar to those of volatile general anesthetics, and that multi-target mechanisms likely underlie their pharmacology.
Collapse
|
18
|
Weiser BP, Bu W, Wong D, Eckenhoff RG. Sites and functional consequence of VDAC-alkylphenol anesthetic interactions. FEBS Lett 2014; 588:4398-403. [PMID: 25448677 DOI: 10.1016/j.febslet.2014.10.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2014] [Revised: 09/10/2014] [Accepted: 10/10/2014] [Indexed: 10/24/2022]
Abstract
General anesthetics have previously been shown to bind mitochondrial VDAC. Here, using a photoactive analog of the anesthetic propofol, we determined that alkylphenol anesthetics bind to Gly56 and Val184 on rat VDAC1. By reconstituting rat VDAC into planar bilayers, we determined that propofol potentiates VDAC gating with asymmetry at the voltage polarities; in contrast, propofol does not affect the conductance of open VDAC. Additional experiments showed that propofol also does not affect gramicidin A properties that are sensitive to lipid bilayer mechanics. Together, this suggests propofol affects VDAC function through direct protein binding, likely at the lipid-exposed channel surface, and that gating can be modulated by ligand binding to the distal ends of VDAC β-strands where Gly56 and Val184 are located.
Collapse
Affiliation(s)
- Brian P Weiser
- Department of Anesthesiology and Critical Care, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, United States; Department of Pharmacology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, United States
| | - Weiming Bu
- Department of Anesthesiology and Critical Care, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, United States
| | - David Wong
- Drexel University College of Medicine, Philadelphia, PA 19129, United States
| | - Roderic G Eckenhoff
- Department of Anesthesiology and Critical Care, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, United States.
| |
Collapse
|