1
|
Mei N, Liang J, McRae DM, Leonenko Z. Localized surface plasmon resonance and atomic force microscopy study of model lipid membranes and their interactions with amyloid and melatonin. NANOTECHNOLOGY 2024; 35:305101. [PMID: 38636478 DOI: 10.1088/1361-6528/ad403b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Accepted: 04/18/2024] [Indexed: 04/20/2024]
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by the accumulation of amyloid plaques in the brain. The toxicity of amyloid to neuronal cell surfaces arises from interactions between small intermediate aggregates, namely amyloid oligomers, and the cell membrane. The nature of these interactions changes with age and disease progression. In our previous work, we demonstrated that both membrane composition and nanoscale structure play crucial roles in amyloid toxicity, and that membrane models mimicking healthy neuron were less affected by amyloid than model membranes mimicking AD neuronal membranes. This understanding introduces the possibility of modifying membrane properties with membrane-active molecules, such as melatonin, to protect them from amyloid-induced damage. In this study, we employed atomic force microscopy and localized surface plasmon resonance to investigate the protective effects of melatonin. We utilized synthetic lipid membranes that mimic the neuronal cellular membrane at various stages of AD and explored their interactions with amyloid-β(1-42) in the presence of melatonin. Our findings reveal that the early diseased membrane model is particularly vulnerable to amyloid binding and subsequent damage. However, melatonin exerts its most potent protective effect on this early-stage membrane. These results suggest that melatonin could act at the membrane level to alleviate amyloid toxicity, offering the most protection during the initial stages of AD.
Collapse
Affiliation(s)
- Nanqin Mei
- Department of Physics and Astronomy, University of Waterloo, Waterloo, ON, N2L 3G1, Canada
- Waterloo Institute for Nanotechnology, University of Waterloo, Waterloo, ON, N2L 3G1, Canada
| | - Jingwen Liang
- Department of Physics and Astronomy, University of Waterloo, Waterloo, ON, N2L 3G1, Canada
| | - Danielle M McRae
- Department of Physics and Astronomy, University of Waterloo, Waterloo, ON, N2L 3G1, Canada
| | - Zoya Leonenko
- Department of Physics and Astronomy, University of Waterloo, Waterloo, ON, N2L 3G1, Canada
- Waterloo Institute for Nanotechnology, University of Waterloo, Waterloo, ON, N2L 3G1, Canada
- Department of Biology, University of Waterloo, Waterloo, ON, N2L 3G1, Canada
| |
Collapse
|
2
|
Ivankov O, Kondela T, Dushanov EB, Ermakova EV, Murugova TN, Soloviov D, Kuklin AI, Kučerka N. Cholesterol and melatonin regulated membrane fluidity does not affect the membrane breakage triggered by amyloid-beta peptide. Biophys Chem 2023; 298:107023. [PMID: 37148823 DOI: 10.1016/j.bpc.2023.107023] [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: 01/01/2023] [Revised: 04/12/2023] [Accepted: 04/12/2023] [Indexed: 05/08/2023]
Abstract
We have studied by means of small angle neutron scattering and diffraction, and molecular dynamics simulations the effect of lipid membrane fluidity on the amyloid-beta peptide interactions with the membrane. These interactions have been discovered previously to trigger the reorganization of model membranes between unilamellar vesicles and planar membranes (bicelle-like structures) during the lipid phase transition. The morphology changes were taking place in rigid membranes prepared of fully saturated lipids and were proposed to play a role in the onset of amyloid related disorders. We show in this study that the replacement of fully saturated lipids by more fluid mono-unsaturated lipids eliminates the mentioned morphology changes, most likely due to the absence of phase transition within the temperature range investigated. We have therefore controlled the membrane rigidity also while ensuring the presence of membrane phase transition within the biologically relevant temperatures. It was done by the addition of melatonin and/or cholesterol to the initial membranes made of saturated lipids. Small angle neutron scattering experiments performed over a range of cholesterol and melatonin concentrations show their distinctive effects on the local membrane structure only. The cholesterol for example affects the membrane curvature such that spontaneously formed unilamellar vesicles are of much larger sizes than those formed by the neat lipid membranes or membranes with melatonin added. The temperature dependent experiments, however, reveal no influence on the previously discovered membrane breakage whether cholesterol or melatonin have been added.
Collapse
Affiliation(s)
- O Ivankov
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Dubna 141980, Russia.
| | - T Kondela
- Department of Nuclear Physics and Biophysics, Faculty of Mathematics, Physics and Informatics, Comenius University Bratislava, Bratislava 842 48, Slovakia
| | - E B Dushanov
- Laboratory of Radiation Biology, Joint Institute for Nuclear Research, Dubna 141980, Russia
| | - E V Ermakova
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Dubna 141980, Russia
| | - T N Murugova
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Dubna 141980, Russia
| | - D Soloviov
- European Molecular Biology Laboratory (EMBL), Hamburg Outstation c/o DESY, Notkestrasse 85, 22607 Hamburg, Germany
| | - A I Kuklin
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Dubna 141980, Russia; Research Center for Molecular Mechanisms of Aging and Age-related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny 141701, Russia
| | - N Kučerka
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Dubna 141980, Russia; Department of Physical Chemistry of Drugs, Faculty of Pharmacy, Comenius University Bratislava, Bratislava SK-832 32, Slovakia.
| |
Collapse
|
3
|
Markowska M, Niemczyk S, Romejko K. Melatonin Treatment in Kidney Diseases. Cells 2023; 12:cells12060838. [PMID: 36980179 PMCID: PMC10047594 DOI: 10.3390/cells12060838] [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: 01/18/2023] [Revised: 03/01/2023] [Accepted: 03/07/2023] [Indexed: 03/11/2023] Open
Abstract
Melatonin is a neurohormone that is mainly secreted by the pineal gland. It coordinates the work of the superior biological clock and consequently affects many processes in the human body. Disorders of the waking and sleeping period result in nervous system imbalance and generate metabolic and endocrine derangements. The purpose of this review is to provide information regarding the potential benefits of melatonin use, particularly in kidney diseases. The impact on the cardiovascular system, diabetes, and homeostasis causes melatonin to be indirectly connected to kidney function and quality of life in people with chronic kidney disease. Moreover, there are numerous reports showing that melatonin plays a role as an antioxidant, free radical scavenger, and cytoprotective agent. This means that the supplementation of melatonin can be helpful in almost every type of kidney injury because inflammation, apoptosis, and oxidative stress occur, regardless of the mechanism. The administration of melatonin has a renoprotective effect and inhibits the progression of complications connected to renal failure. It is very important that exogenous melatonin supplementation is well tolerated and that the number of side effects caused by this type of treatment is low.
Collapse
|
4
|
Xue M, Cao Y, Shen C, Guo W. Computational Advances of Protein/Neurotransmitter-membrane Interactions Involved in Vesicle Fusion and Neurotransmitter Release. J Mol Biol 2023; 435:167818. [PMID: 36089056 DOI: 10.1016/j.jmb.2022.167818] [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: 05/31/2022] [Revised: 08/22/2022] [Accepted: 09/04/2022] [Indexed: 02/04/2023]
Abstract
Vesicle fusion is of crucial importance to neuronal communication at neuron terminals. The exquisite but complex fusion machinery for neurotransmitter release is tightly controlled and regulated by protein/neurotransmitter-membrane interactions. Computational 'microscopies', in particular molecular dynamics simulations and related techniques, have provided notable insight into the physiological process over the past decades, and have made enormous contributions to fields such as neurology, pharmacology and pathophysiology. Here we review the computational advances of protein/neurotransmitter-membrane interactions related to presynaptic vesicle-membrane fusion and neurotransmitter release, and outline the in silico challenges ahead for understanding this important physiological process.
Collapse
Affiliation(s)
- Minmin Xue
- Key Laboratory for Intelligent Nano Materials and Devices of Ministry of Education, State Key Laboratory of Mechanics and Control of Mechanical Structures, and Institute for Frontier Science, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China
| | - Yuwei Cao
- State Key Laboratory of Tribology, Department of Mechanical Engineering, Tsinghua University, Beijing, China
| | - Chun Shen
- Key Laboratory for Intelligent Nano Materials and Devices of Ministry of Education, State Key Laboratory of Mechanics and Control of Mechanical Structures, and Institute for Frontier Science, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China.
| | - Wanlin Guo
- Key Laboratory for Intelligent Nano Materials and Devices of Ministry of Education, State Key Laboratory of Mechanics and Control of Mechanical Structures, and Institute for Frontier Science, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China; State Key Laboratory of Tribology, Department of Mechanical Engineering, Tsinghua University, Beijing, China.
| |
Collapse
|
5
|
Somjid S, Shinsuphan N, Temprom L, Krongsuk S. Effects of cholesterol and temperature on structural properties and dynamic behavior of niosome bilayers with melatonin Inclusion: A Coarse-Grained simulation study. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.120686] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
6
|
Katata VM, Maximino MD, Silva CY, Alessio P. The Role of Cholesterol in the Interaction of the Lipid Monolayer with the Endocrine Disruptor Bisphenol-A. MEMBRANES 2022; 12:membranes12080729. [PMID: 35893447 PMCID: PMC9332047 DOI: 10.3390/membranes12080729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 06/30/2022] [Accepted: 07/05/2022] [Indexed: 11/16/2022]
Abstract
Among pollutants of emerging concern, endocrine disruptors (ED) have been shown to cause side effects in humans and animals. Bisphenol-A (BPA) is an ED by-product of the plastic industry and one of the chemicals with the highest volume produced yearly. Here, we studied the role of cholesterol in the BPA exposure effects over membrane models. We used Langmuir films of both neat lipid DPPC (1,2-dipalmitoyl-sn-glycero-3-phosphocholine) and cholesterol (Chol) and a binary mixture containing DPPC/Chol, exposing it to BPA. We evaluate changes in the π-A isotherms and the PM–IRRAS (polarization modulation–infrared reflection adsorption spectroscopy) spectra. BPA exposure induced changes in the DPPC and Chol neat monolayers, causing mean molecular area expansion and altering profiles. However, at high surface pressure, the BPA was expelled from the air–water interface. For the DPPC/Chol mixture, BPA caused expansion throughout the whole compression, indicating that BPA is present at the monolayer interface. The PM–IRRAS analysis showed that BPA interacted with the phosphate group of DPPC through hydrogen bonding, which caused the area’s expansion. Such evidence might be biologically relevant to better understand the mechanism of action of BPA in cell membranes once phosphatidylcholines and Chol are found in mammalian membranes.
Collapse
|
7
|
Loh D, Reiter RJ. Melatonin: Regulation of Prion Protein Phase Separation in Cancer Multidrug Resistance. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27030705. [PMID: 35163973 PMCID: PMC8839844 DOI: 10.3390/molecules27030705] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 01/11/2022] [Accepted: 01/17/2022] [Indexed: 12/13/2022]
Abstract
The unique ability to adapt and thrive in inhospitable, stressful tumor microenvironments (TME) also renders cancer cells resistant to traditional chemotherapeutic treatments and/or novel pharmaceuticals. Cancer cells exhibit extensive metabolic alterations involving hypoxia, accelerated glycolysis, oxidative stress, and increased extracellular ATP that may activate ancient, conserved prion adaptive response strategies that exacerbate multidrug resistance (MDR) by exploiting cellular stress to increase cancer metastatic potential and stemness, balance proliferation and differentiation, and amplify resistance to apoptosis. The regulation of prions in MDR is further complicated by important, putative physiological functions of ligand-binding and signal transduction. Melatonin is capable of both enhancing physiological functions and inhibiting oncogenic properties of prion proteins. Through regulation of phase separation of the prion N-terminal domain which targets and interacts with lipid rafts, melatonin may prevent conformational changes that can result in aggregation and/or conversion to pathological, infectious isoforms. As a cancer therapy adjuvant, melatonin could modulate TME oxidative stress levels and hypoxia, reverse pH gradient changes, reduce lipid peroxidation, and protect lipid raft compositions to suppress prion-mediated, non-Mendelian, heritable, but often reversible epigenetic adaptations that facilitate cancer heterogeneity, stemness, metastasis, and drug resistance. This review examines some of the mechanisms that may balance physiological and pathological effects of prions and prion-like proteins achieved through the synergistic use of melatonin to ameliorate MDR, which remains a challenge in cancer treatment.
Collapse
Affiliation(s)
- Doris Loh
- Independent Researcher, Marble Falls, TX 78654, USA
- Correspondence: (D.L.); (R.J.R.)
| | - Russel J. Reiter
- Department of Cellular and Structural Biology, UT Health San Antonio, San Antonio, TX 78229, USA
- Correspondence: (D.L.); (R.J.R.)
| |
Collapse
|
8
|
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
|
9
|
Loh D, Reiter RJ. Melatonin: Regulation of Biomolecular Condensates in Neurodegenerative Disorders. Antioxidants (Basel) 2021; 10:1483. [PMID: 34573116 PMCID: PMC8465482 DOI: 10.3390/antiox10091483] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 09/10/2021] [Accepted: 09/13/2021] [Indexed: 12/12/2022] Open
Abstract
Biomolecular condensates are membraneless organelles (MLOs) that form dynamic, chemically distinct subcellular compartments organizing macromolecules such as proteins, RNA, and DNA in unicellular prokaryotic bacteria and complex eukaryotic cells. Separated from surrounding environments, MLOs in the nucleoplasm, cytoplasm, and mitochondria assemble by liquid-liquid phase separation (LLPS) into transient, non-static, liquid-like droplets that regulate essential molecular functions. LLPS is primarily controlled by post-translational modifications (PTMs) that fine-tune the balance between attractive and repulsive charge states and/or binding motifs of proteins. Aberrant phase separation due to dysregulated membrane lipid rafts and/or PTMs, as well as the absence of adequate hydrotropic small molecules such as ATP, or the presence of specific RNA proteins can cause pathological protein aggregation in neurodegenerative disorders. Melatonin may exert a dominant influence over phase separation in biomolecular condensates by optimizing membrane and MLO interdependent reactions through stabilizing lipid raft domains, reducing line tension, and maintaining negative membrane curvature and fluidity. As a potent antioxidant, melatonin protects cardiolipin and other membrane lipids from peroxidation cascades, supporting protein trafficking, signaling, ion channel activities, and ATPase functionality during condensate coacervation or dissolution. Melatonin may even control condensate LLPS through PTM and balance mRNA- and RNA-binding protein composition by regulating N6-methyladenosine (m6A) modifications. There is currently a lack of pharmaceuticals targeting neurodegenerative disorders via the regulation of phase separation. The potential of melatonin in the modulation of biomolecular condensate in the attenuation of aberrant condensate aggregation in neurodegenerative disorders is discussed in this review.
Collapse
Affiliation(s)
- Doris Loh
- Independent Researcher, Marble Falls, TX 78654, USA
| | - Russel J. Reiter
- Department of Cellular and Structural Biology, UT Health Science Center, San Antonio, TX 78229, USA
| |
Collapse
|
10
|
Ritwiset A, Khajonrit J, Krongsuk S, Maensiri S. Molecular insight on the formation structure and dynamics of melatonin in an aqueous solution and at the Water-Air interface: A molecular dynamics study. J Mol Graph Model 2021; 108:107983. [PMID: 34274727 DOI: 10.1016/j.jmgm.2021.107983] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 06/27/2021] [Accepted: 07/05/2021] [Indexed: 11/18/2022]
Abstract
Melatonin is a natural hormone that has been shown highly antioxidant effects. Consequently, it has been extensively studied for its therapeutic potential in several diseases such as insomnia, cardiovascular, Alzheimer, and certain types of cancers. Recently, it has been used to adjuvant treatment for COVID-19 patients. It is well-known that melatonin is highly hydrophobic, resulting in lower solubility. However, the molecular structure and dynamic behavior of the formation of melatonin in an aqueous solution and at the water-air interface have not yet been clearly explained. This information is necessary for the melatonin formulation in drug delivery systems. The present work focuses on the molecular structure and dynamics of melatonin molecules in the aqueous solution and at the water-air interface based on using a molecular dynamics simulation study. The results showed that most melatonin molecules were aggregated in an aqueous solution while they were formed a self-assembled monolayer with the ordered structure at the water-air interface. The strong interaction of melatonin depends on their functional group which showed a similar trend for both systems and was sequenced as follows: carbonyl O > indole NH > amide NH > methoxy OA, respectively. However, the carbonyl O and the indole NH groups exhibit strong interactions with water molecules at the interface. Consequently, the two preferred orientations of the melatonin head group can be observed at the water-air interface (i.e., one is to turn the head group to the water surface with the tilted angle of ~40°-60° and the second one is to turn the head group away from the water surface with the tilted angle of ~130°). The longer lifetime of hydrogen bonds formed between melatonin themselves in the bulk water reveals that the stability of melatonin aggregation in an aqueous solution is more stable. Therefore, melatonin has less soluble in an aqueous solution.
Collapse
Affiliation(s)
- Aksornnarong Ritwiset
- School of Physics, Institute of Science, Suranaree University of Technology, Nakhon Ratchasima, 30000, Thailand
| | - Jessada Khajonrit
- School of Physics, Institute of Science, Suranaree University of Technology, Nakhon Ratchasima, 30000, Thailand
| | - Sriprajak Krongsuk
- Department of Physics, Faculty of Science, Khon Kaen University, Khon Kaen, 40002, Thailand; Institute of Nanomaterials Research and Innovation for Energy (IN-RIE), Khon Kaen University, Khon Kaen, 40002, Thailand; Institute of Nanomaterials Research and Innovation for Energy (IN-RIE), Research Network of NANOTEC-KKU (RNN), Khon Kaen University, Khon Kaen, 40002, Thailand
| | - Santi Maensiri
- School of Physics, Institute of Science, Suranaree University of Technology, Nakhon Ratchasima, 30000, Thailand; SUT Center of Excellence on Advanced Functional Nanomaterials, Suranaree University of Technology, Nakhon Ratchasima, 30000, Thailand.
| |
Collapse
|
11
|
Kondela T, Dushanov E, Vorobyeva M, Mamatkulov K, Drolle E, Soloviov D, Hrubovčák P, Kholmurodov K, Arzumanyan G, Leonenko Z, Kučerka N. Investigating the competitive effects of cholesterol and melatonin in model lipid membranes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2021; 1863:183651. [PMID: 34023300 DOI: 10.1016/j.bbamem.2021.183651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 05/11/2021] [Accepted: 05/14/2021] [Indexed: 10/21/2022]
Abstract
We have studied the impact of cholesterol and/or melatonin on the static and dynamical properties of bilayers made of DPPC or DOPC utilizing neutron scattering techniques, Raman spectroscopy and molecular dynamics simulations. While differing in the amplitude of the effect due to cholesterol or melatonin when comparing their interactions with the two lipids, their addition ensued recognizable changes to both types of bilayers. As expected, based on the two-component systems of lipid/cholesterol or lipid/melatonin studied previously, we show the impact of cholesterol and melatonin being opposite and competitive in the case of three-component systems of lipid/cholesterol/melatonin. The effect of cholesterol appears to prevail over that of melatonin in the case of structural properties of DPPC-based bilayers, which can be explained by its interactions targeting primarily the saturated lipid chains. The dynamics of hydrocarbon chains represented by the ratio of trans/gauche conformers reveals the competitive effect of cholesterol and melatonin being somewhat more balanced. The additive yet opposing effects of cholesterol and melatonin have been observed also in the case of structural properties of DOPC-based bilayers. We report that cholesterol induced an increase in bilayer thickness, while melatonin induced a decrease in bilayer thickness in the three-component systems of DOPC/cholesterol/melatonin. Commensurately, by evaluating the projected area of DOPC, we demonstrate a lipid area decrease with an increasing concentration of cholesterol, and a lipid area increase with an increasing concentration of melatonin. The demonstrated condensing effect of cholesterol and the fluidizing effect of melatonin appear in an additive manner upon their mutual presence.
Collapse
Affiliation(s)
- Tomáš Kondela
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Joliot-Curie 6, Dubna, Moscow Region 141980, Russian Federation; Faculty of Mathematics, Physics and Informatics, Comenius University in Bratislava, Mlynska dolina, Bratislava 842 48, Slovakia
| | - Ermuhammad Dushanov
- Laboratory of Radiation Biology, Joint Institute for Nuclear Research, Joliot-Curie 6, Dubna, Moscow Region 141980, Russian Federation; Department of Biophysics, Dubna State University, Universitetskaya 19, Dubna, Moscow Region 141980, Russian Federation
| | - Maria Vorobyeva
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Joliot-Curie 6, Dubna, Moscow Region 141980, Russian Federation
| | - Kahramon Mamatkulov
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Joliot-Curie 6, Dubna, Moscow Region 141980, Russian Federation
| | - Elizabeth Drolle
- Department of Biology, University of Waterloo, Waterloo, Ontario, Canada
| | - Dmytro Soloviov
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Joliot-Curie 6, Dubna, Moscow Region 141980, Russian Federation; Faculty of Physics, Taras Shevchenko National University of Kyiv, Hlushkova Ave. 4, Kyiv 03127, Ukraine
| | - Pavol Hrubovčák
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Joliot-Curie 6, Dubna, Moscow Region 141980, Russian Federation; Department of Condensed Matter Physics, P. J. Šafárik University, Park Angelinum 9, Košice 04154, Slovakia
| | - Kholmirzo Kholmurodov
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Joliot-Curie 6, Dubna, Moscow Region 141980, Russian Federation; Department of Chemistry, New Technologies and Materials, Dubna State University, Universitetskaya 19, Dubna, Moscow Region 141980, Russian Federation
| | - Grigory Arzumanyan
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Joliot-Curie 6, Dubna, Moscow Region 141980, Russian Federation
| | - Zoya Leonenko
- Department of Biology, University of Waterloo, Waterloo, Ontario, Canada; Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario, Canada
| | - Norbert Kučerka
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Joliot-Curie 6, Dubna, Moscow Region 141980, Russian Federation; Department of Physical Chemistry of Drugs, Faculty of Pharmacy, Comenius University in Bratislava, Odbojárov 10, Bratislava 832 32, Slovakia.
| |
Collapse
|
12
|
Sharifian Gh M. Recent Experimental Developments in Studying Passive Membrane Transport of Drug Molecules. Mol Pharm 2021; 18:2122-2141. [PMID: 33914545 DOI: 10.1021/acs.molpharmaceut.1c00009] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The ability to measure the passive membrane permeation of drug-like molecules is of fundamental biological and pharmaceutical importance. Of significance, passive diffusion across the cellular membranes plays an effective role in the delivery of many pharmaceutical agents to intracellular targets. Hence, approaches for quantitative measurement of membrane permeability have been the topics of research for decades, resulting in sophisticated biomimetic systems coupled with advanced techniques. In this review, recent developments in experimental approaches along with theoretical models for quantitative and real-time analysis of membrane transport of drug-like molecules through mimetic and living cell membranes are discussed. The focus is on time-resolved fluorescence-based, surface plasmon resonance, and second-harmonic light scattering approaches. The current understanding of how properties of the membrane and permeant affect the permeation process is discussed.
Collapse
Affiliation(s)
- Mohammad Sharifian Gh
- Department of Cell Biology, University of Virginia, Charlottesville, Virginia 22908, United States
| |
Collapse
|
13
|
Martí J, Lu H. Microscopic Interactions of Melatonin, Serotonin and Tryptophan with Zwitterionic Phospholipid Membranes. Int J Mol Sci 2021; 22:2842. [PMID: 33799606 PMCID: PMC8001758 DOI: 10.3390/ijms22062842] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 03/05/2021] [Accepted: 03/08/2021] [Indexed: 12/15/2022] Open
Abstract
The interactions at the atomic level between small molecules and the main components of cellular plasma membranes are crucial for elucidating the mechanisms allowing for the entrance of such small species inside the cell. We have performed molecular dynamics and metadynamics simulations of tryptophan, serotonin, and melatonin at the interface of zwitterionic phospholipid bilayers. In this work, we will review recent computer simulation developments and report microscopic properties, such as the area per lipid and thickness of the membranes, atomic radial distribution functions, angular orientations, and free energy landscapes of small molecule binding to the membrane. Cholesterol affects the behaviour of the small molecules, which are mainly buried in the interfacial regions. We have observed a competition between the binding of small molecules to phospholipids and cholesterol through lipidic hydrogen-bonds. Free energy barriers that are associated to translational and orientational changes of melatonin have been found to be between 10-20 kJ/mol for distances of 1 nm between melatonin and the center of the membrane. Corresponding barriers for tryptophan and serotonin that are obtained from reversible work methods are of the order of 10 kJ/mol and reveal strong hydrogen bonding between such species and specific phospholipid sites. The diffusion of tryptophan and melatonin is of the order of 10-7 cm2/s for the cholesterol-free and cholesterol-rich setups.
Collapse
Affiliation(s)
- Jordi Martí
- Department of Physics, Technical University of Catalonia-Barcelona Tech, 08034 Barcelona, Spain
| | - Huixia Lu
- School of Pharmacy, Shanghai Jiaotong University, Shanghai 200240, China;
| |
Collapse
|
14
|
Moss III FR, Cabrera GE, McKenna GM, Salerno GJ, Shuken SR, Landry ML, Weiss TM, Burns NZ, Boxer SG. Halogenation-Dependent Effects of the Chlorosulfolipids of Ochromonas danica on Lipid Bilayers. ACS Chem Biol 2020; 15:2986-2995. [PMID: 33035052 DOI: 10.1021/acschembio.0c00624] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The chlorosulfolipids are amphiphilic natural products with stereochemically complex patterns of chlorination and sulfation. Despite their role in toxic shellfish poisoning, potential pharmacological activities, and unknown biological roles, they remain understudied due to the difficulties in purifying them from natural sources. The structure of these molecules, with a charged sulfate group in the middle of the hydrophobic chain, appears incompatible with the conventional lipid bilayer structure. Questions about chlorosulfolipids remain unanswered partly due to the unavailability of structural analogues with which to conduct structure-function studies. We approach this problem by combining enantioselective total synthesis and membrane biophysics. Using a combination of Langmuir pressure-area isotherms of lipid monolayers, fluorescence imaging of vesicles, mass spectrometry imaging, natural product isolation, small-angle X-ray scattering, and cryogenic electron microscopy, we show that danicalipin A (1) likely inserts into lipid bilayers in the headgroup region and alters their structure and phase behavior. Specifically, danicalipin A (1) thins the bilayer and fluidizes it, allowing even saturated lipid to form fluid bilayers. Lipid monolayers show similar fluidizing upon insertion of danicalipin A (1). Furthermore, we show that the halogenation of the molecule is critical for its membrane activity, likely due to sterically controlled conformational changes. Synthetic unchlorinated and monochlorinated analogues do not thin and fluidize lipid bilayers to the same extent as the natural product. Overall, this study sheds light on how amphiphilic small molecules interact with lipid bilayers and the importance of stereochemistry and halogenation for this interaction.
Collapse
Affiliation(s)
- Frank R. Moss III
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Gabrielle E. Cabrera
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Grace M. McKenna
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Giulio J. Salerno
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Steven R. Shuken
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Matthew L. Landry
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Thomas M. Weiss
- Stanford Synchrotron Radiation Laboratory, Stanford Linear Accelerator Center, Stanford University, Menlo Park, California 94025, United States
| | - Noah Z. Burns
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Steven G. Boxer
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| |
Collapse
|
15
|
Mei N, Robinson M, Davis JH, Leonenko Z. Melatonin Alters Fluid Phase Coexistence in POPC/DPPC/Cholesterol Membranes. Biophys J 2020; 119:2391-2402. [PMID: 33157120 DOI: 10.1016/j.bpj.2020.10.030] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 08/30/2020] [Accepted: 10/21/2020] [Indexed: 12/22/2022] Open
Abstract
The structure and biophysical properties of lipid membranes are important for cellular functions in health and disease. In Alzheimer's disease, the neuronal membrane is a target for toxic amyloid-β (Aβ). Melatonin is an important pineal gland hormone that has been shown to protect against Aβ toxicity in cellular and animal studies, but the molecular mechanism of this protection is not fully understood. Melatonin is a small membrane-active molecule that has been shown to interact with model lipid membranes and alter the membrane biophysical properties, such as membrane molecular order and dynamics. This effect of melatonin has been previously studied in simple model bilayers with one or two lipid components. To make it more relevant to neuronal membranes, we used a more complex ternary lipid mixture as our membrane model. In this study, we used 2H-NMR to investigate the effect of melatonin on the phase behavior of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC), 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC), and cholesterol lipid membranes. We used deuterium-labeled POPC-d31 and DPPC-d62,separately to probe the changes in hydrocarbon chain order as a function of temperature and melatonin concentration. We find that POPC/DPPC/cholesterol at molar proportions of 3:3:2 is close to liquid-disordered/liquid-ordered phase separation and that melatonin can induce phase separation in these ternary mixtures by preferentially incorporating into the disordered phase and increasing its level of disorder. At 5 mol% melatonin, we observed phase separation in samples with POPC-d31, but not with DPPC-d62, whereas at 10 mol% melatonin, phase separation was observed in both samples with either POPC-d31 or DPPC-d62. These results indicate that melatonin can have a strong effect on membrane structure and physical properties, which may provide some clues to understanding how melatonin protects against Aβ, and that choice of chain perdeuteration is an important consideration from a technical point of view.
Collapse
Affiliation(s)
- Nanqin Mei
- Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario, Canada
| | - Morgan Robinson
- Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario, Canada; Department of Biology, University of Waterloo, Waterloo, Ontario, Canada
| | - James H Davis
- Department of Physics, University of Guelph, Guelph, Ontario, Canada.
| | - Zoya Leonenko
- Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario, Canada; Department of Biology, University of Waterloo, Waterloo, Ontario, Canada; Waterloo Institute of Nanotechnology, University of Waterloo, Waterloo, Ontario, Canada.
| |
Collapse
|
16
|
Melatonin regulates Aβ production/clearance balance and Aβ neurotoxicity: A potential therapeutic molecule for Alzheimer's disease. Biomed Pharmacother 2020; 132:110887. [PMID: 33254429 DOI: 10.1016/j.biopha.2020.110887] [Citation(s) in RCA: 86] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 10/07/2020] [Accepted: 10/12/2020] [Indexed: 02/06/2023] Open
Abstract
Alzheimer's disease (AD) is an age-related neurodegenerative disease with multiple predisposing factors and complicated pathogenesis. Aβ peptide is one of the most important pathogenic factors in the etiology of AD. Accumulating evidence indicates that the imbalance of Aβ production and Aβ clearance in the brain of AD patients leads to Aβ deposition and neurotoxic Aβ oligomer formation. Melatonin shows a potent neuroprotective effect and can prevent or slow down the progression of AD, supporting the view that melatonin is a potential therapeutic molecule for AD. Melatonin modulates the regulatory network of secretase expression and affects the function of secretase, thereby inhibiting amyloidogenic APP processing and Aβ production. Additionally, melatonin ameliorates Aβ-induced neurotoxicity and probably promotes Aβ clearance through glymphatic-lymphatic drainage, BBB transportation and degradation pathways. In this review, we summarize and discuss the role of melatonin against Aβ-dependent AD pathogenesis. We explore the potential cellular and molecular mechanisms of melatonin on Aβ production and assembly, Aβ clearance, Aβ neurotoxicity and circadian cycle disruption. We summarize multiple clinical trials of melatonin treatment in AD patients, showing that melatonin has a promising effect on improving sleep quality and cognitive function. This review aims to stimulate further research on melatonin as a potential therapeutic agent for AD.
Collapse
|
17
|
The effects of melatonin, serotonin, tryptophan and NAS on the biophysical properties of DPPC monolayers. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183363. [DOI: 10.1016/j.bbamem.2020.183363] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 05/15/2020] [Accepted: 05/18/2020] [Indexed: 12/24/2022]
|
18
|
Lolicato F, Juhola H, Zak A, Postila PA, Saukko A, Rissanen S, Enkavi G, Vattulainen I, Kepczynski M, Róg T. Membrane-Dependent Binding and Entry Mechanism of Dopamine into Its Receptor. ACS Chem Neurosci 2020; 11:1914-1924. [PMID: 32538079 PMCID: PMC7735663 DOI: 10.1021/acschemneuro.9b00656] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Synaptic neurotransmission has recently been proposed to function via either a membrane-independent or a membrane-dependent mechanism, depending on the neurotransmitter type. In the membrane-dependent mechanism, amphipathic neurotransmitters first partition to the lipid headgroup region and then diffuse along the membrane plane to their membrane-buried receptors. However, to date, this mechanism has not been demonstrated for any neurotransmitter-receptor complex. Here, we combined isothermal calorimetry measurements with a diverse set of molecular dynamics simulation methods to investigate the partitioning of an amphipathic neurotransmitter (dopamine) and the mechanism of its entry into the ligand-binding site. Our results show that the binding of dopamine to its receptor is consistent with the membrane-dependent binding and entry mechanism. Both experimental and simulation results showed that dopamine favors binding to lipid membranes especially in the headgroup region. Moreover, our simulations revealed a ligand-entry pathway from the membrane to the binding site. This pathway passes through a lateral gate between transmembrane alpha-helices 5 and 6 on the membrane-facing side of the protein. All in all, our results demonstrate that dopamine binds to its receptor by a membrane-dependent mechanism, and this is complemented by the more traditional binding mechanism directly through the aqueous phase. The results suggest that the membrane-dependent mechanism is common in other synaptic receptors, too.
Collapse
Affiliation(s)
- Fabio Lolicato
- Department of Physics, University of Helsinki, P.O. Box 64, FI-00014 Helsinki, Finland
- Biochemistry Center, Heidelberg University, D-69120 Heidelberg, Germany
| | - Hanna Juhola
- Computational Physics Laboratory, Tampere University, FI-33100 Tampere, Finland
| | - Agata Zak
- Faculty of Chemistry, Jagiellonian University, Gronostajowa 2, 30-387 Kraków, Poland
| | - Pekka A. Postila
- Institute of Biomedicine, Faculty of Medicine, University of Turku, FI-20014 Turku, Finland
| | - Annina Saukko
- Department of Applied Physics, University of Eastern Finland, P.O.B. 1627, FI-70211 Kuopio, Finland
- Department of Medical Physics, Turku University Hospital, FI-20520 Turku, Finland
| | - Sami Rissanen
- Computational Physics Laboratory, Tampere University, FI-33100 Tampere, Finland
| | - Giray Enkavi
- Department of Physics, University of Helsinki, P.O. Box 64, FI-00014 Helsinki, Finland
| | - Ilpo Vattulainen
- Department of Physics, University of Helsinki, P.O. Box 64, FI-00014 Helsinki, Finland
- Computational Physics Laboratory, Tampere University, FI-33100 Tampere, Finland
- MEMPHYS − Center for Biomembrane Physics
| | - Mariusz Kepczynski
- Faculty of Chemistry, Jagiellonian University, Gronostajowa 2, 30-387 Kraków, Poland
| | - Tomasz Róg
- Department of Physics, University of Helsinki, P.O. Box 64, FI-00014 Helsinki, Finland
| |
Collapse
|
19
|
Cellular absorption of small molecules: free energy landscapes of melatonin binding at phospholipid membranes. Sci Rep 2020; 10:9235. [PMID: 32513935 PMCID: PMC7280225 DOI: 10.1038/s41598-020-65753-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2019] [Accepted: 05/05/2020] [Indexed: 12/28/2022] Open
Abstract
Free energy calculations are essential to unveil mechanisms at the atomic scale such as binding of small solutes and their translocation across cell membranes, eventually producing cellular absorption. Melatonin regulates biological rhythms and is directly related to carcinogenesis and neurodegenerative disorders. Free energy landscapes obtained from well-tempered metadynamics simulations precisely describe the characteristics of melatonin binding to specific sites in the membrane and reveal the role of cholesterol in free energy barrier crossing. A specific molecular torsional angle and the distance between melatonin and the center of the membrane along the normal to the membrane Z-axis have been considered as suitable reaction coordinates. Free energy barriers between two particular orientations of the molecular structure (folded and extended) have been found to be of about 18 kJ/mol for z-distances of about 1–2 nm. The ability of cholesterol to expel melatonin out of the internal regions of the membrane towards the interface and the external solvent is explained from a free energy perspective. The calculations reported here offer detailed free energy landscapes of melatonin embedded in model cell membranes and reveal microscopic information on its transition between free energy minima, including the location of relevant transition states, and provide clues on the role of cholesterol in the cellular absorption of small molecules.
Collapse
|
20
|
Josey BP, Heinrich F, Silin V, Lösche M. Association of Model Neurotransmitters with Lipid Bilayer Membranes. Biophys J 2020; 118:1044-1057. [PMID: 32032504 DOI: 10.1016/j.bpj.2020.01.016] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Revised: 01/08/2020] [Accepted: 01/15/2020] [Indexed: 11/15/2022] Open
Abstract
Aimed at reproducing the results of electrophysiological studies of synaptic signal transduction, conventional models of neurotransmission are based on the specific binding of neurotransmitters to ligand-gated receptor ion channels. However, the complex kinetic behavior observed in synaptic transmission cannot be reproduced in a standard kinetic model without the ad hoc postulation of additional conformational channel states. On the other hand, if one invokes unspecific neurotransmitter adsorption to the bilayer-a process not considered in the established models-the electrophysiological data can be rationalized with only the standard set of three conformational receptor states that also depend on this indirect coupling of neurotransmitters via their membrane interaction. Experimental verification has been difficult because binding affinities of neurotransmitters to the lipid bilayer are low. We quantify this interaction with surface plasmon resonance to measure equilibrium dissociation constants in neurotransmitter membrane association. Neutron reflection measurements on artificial membranes, so-called sparsely tethered bilayer lipid membranes, reveal the structural aspects of neurotransmitters' association with zwitterionic and anionic bilayers. We thus establish that serotonin interacts nonspecifically with the membrane at physiologically relevant concentrations, whereas γ-aminobutyric acid does not. Surface plasmon resonance shows that serotonin adsorbs with millimolar affinity, and neutron reflectometry shows that it penetrates the membrane deeply, whereas γ-aminobutyric is excluded from the bilayer.
Collapse
Affiliation(s)
- Brian P Josey
- Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania
| | - Frank Heinrich
- Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania; National Institute of Standards and Technology, Center for Neutron Research, Gaithersburg, Maryland
| | - Vitalii Silin
- Institute for Bioscience and Biotechnology Research, Rockville, Maryland
| | - Mathias Lösche
- Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania; National Institute of Standards and Technology, Center for Neutron Research, Gaithersburg, Maryland; Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania.
| |
Collapse
|
21
|
Lu H, Martí J. Binding and dynamics of melatonin at the interface of phosphatidylcholine-cholesterol membranes. PLoS One 2019; 14:e0224624. [PMID: 31697738 PMCID: PMC6837308 DOI: 10.1371/journal.pone.0224624] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Accepted: 10/17/2019] [Indexed: 12/18/2022] Open
Abstract
The characterization of interactions between melatonin, one main ingredient of medicines regulating sleeping rhythms, and basic components of cellular plasma membranes (phospholipids, cholesterol, metal ions and water) is very important to elucidate the main mechanisms for the introduction of melatonin into cells and also to identify its local structure and microscopic dynamics. Molecular dynamics simulations of melatonin inside mixtures of dimyristoylphosphatidylcholine and cholesterol in NaCl solution at physiological concentration have been performed at 303.15 K to systematically explore melatonin-cholesterol, melatonin-lipid and melatonin-water interactions. Properties such as the area per lipid and thickness of the membrane as well as selected radial distribution functions, binding free energies, angular distributions, atomic spectral densities and translational diffusion of melatonin are reported. The presence of cholesterol significantly affects the behavior of melatonin, which is mainly buried into the interfaces of membranes. Introducing cholesterol into the system helps melatonin change from folded to extended configurations more easily. Our results suggest that there exists a competition between the binding of melatonin to phospholipids and to cholesterol by means of hydrogen-bonds. Spectral densities of melatonin reported in this work, in overall good agreement with experimental data, revealed the participation of each atom of melatonin to its complete spectrum. Melatonin self-diffusion coefficients are of the order of 10-7 cm2/s and they significantly increase when cholesterol is addeed to the membrane.
Collapse
Affiliation(s)
- Huixia Lu
- Department of Physics, Technical University of Catalonia-Barcelona Tech. Barcelona, Catalonia, Spain
| | - Jordi Martí
- Department of Physics, Technical University of Catalonia-Barcelona Tech. Barcelona, Catalonia, Spain
| |
Collapse
|
22
|
A Perspective: Active Role of Lipids in Neurotransmitter Dynamics. Mol Neurobiol 2019; 57:910-925. [PMID: 31595461 PMCID: PMC7031182 DOI: 10.1007/s12035-019-01775-7] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Accepted: 09/01/2019] [Indexed: 12/30/2022]
Abstract
Synaptic neurotransmission is generally considered as a function of membrane-embedded receptors and ion channels in response to the neurotransmitter (NT) release and binding. This perspective aims to widen the protein-centric view by including another vital component—the synaptic membrane—in the discussion. A vast set of atomistic molecular dynamics simulations and biophysical experiments indicate that NTs are divided into membrane-binding and membrane-nonbinding categories. The binary choice takes place at the water-membrane interface and follows closely the positioning of the receptors’ binding sites in relation to the membrane. Accordingly, when a lipophilic NT is on route to a membrane-buried binding site, it adheres on the membrane and, then, travels along its plane towards the receptor. In contrast, lipophobic NTs, which are destined to bind into receptors with extracellular binding sites, prefer the water phase. This membrane-based sorting splits the neurotransmission into membrane-independent and membrane-dependent mechanisms and should make the NT binding into the receptors more efficient than random diffusion would allow. The potential implications and notable exceptions to the mechanisms are discussed here. Importantly, maintaining specific membrane lipid compositions (MLCs) at the synapses, especially regarding anionic lipids, affect the level of NT-membrane association. These effects provide a plausible link between the MLC imbalances and neurological diseases such as depression or Parkinson’s disease. Moreover, the membrane plays a vital role in other phases of the NT life cycle, including storage and release from the synaptic vesicles, transport from the synaptic cleft, as well as their synthesis and degradation.
Collapse
|
23
|
The Mystery behind the Pineal Gland: Melatonin Affects the Metabolism of Cholesterol. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2019; 2019:4531865. [PMID: 31360294 PMCID: PMC6652030 DOI: 10.1155/2019/4531865] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 05/20/2019] [Accepted: 06/23/2019] [Indexed: 12/17/2022]
Abstract
Melatonin may be considered a cardioprotective agent. Since atherogenesis is partly associated with the metabolism of lipoproteins, it seems plausible that melatonin affects cardiovascular risk by modulating the metabolism of cholesterol and its subfractions. Moreover, cholesterol-driven atherogenesis can be hypothetically reduced by melatonin, mainly due to the minimalization of harmful reactions triggered in the cardiovascular system by the reactive oxygen species-induced toxic derivatives of cholesterol. In this review, we attempted to summarize the available data on the hypolipemizing effects of melatonin, with some emphasis on the molecular mechanisms underlying these reactions. We aimed to attract readers' attention to the numerous gaps of knowledge present in the reviewed field and the essential irrelevance between the findings originating from different sources: clinical observations and in vitro mechanistic and molecular studies, as well as preclinical experiments involving animal models. Overall, such inconsistencies make it currently impossible to give a reliable opinion on the action of melatonin on the metabolism of lipoproteins.
Collapse
|
24
|
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: 173] [Impact Index Per Article: 34.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [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
|
25
|
Koehn JT, Beuning CN, Peters BJ, Dellinger SK, Van Cleave C, Crick DC, Crans DC. Investigating Substrate Analogues for Mycobacterial MenJ: Truncated and Partially Saturated Menaquinones. Biochemistry 2019; 58:1596-1615. [DOI: 10.1021/acs.biochem.9b00007] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
26
|
Santos RMD, Marani F, Chiba FY, Mattera MSDLC, Tsosura TVS, Tessarin GWL, Pereira RF, Belardi BE, Pinheiro BCES, Sumida DH. Melatonin promotes reduction in TNF levels and improves the lipid profile and insulin sensitivity in pinealectomized rats with periodontal disease. Life Sci 2018; 213:32-39. [PMID: 30321542 DOI: 10.1016/j.lfs.2018.09.056] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 09/25/2018] [Accepted: 09/28/2018] [Indexed: 02/04/2023]
Abstract
AIM This study aimed to investigate the effects of melatonin (ME) on insulin resistance (IR) and signaling (IS), proinflammatory cytokine levels, and lipid profiles in pinealectomyzed (PNX) rats with periodontal disease (PD). MAIN METHODS One hundred and forty-four rats (age = 40 days) were distributed into 8 groups: 1) control (CN); 2) PD only; 3) PNX only; 4) PNX and PD (PNXPD); 5) CN treated with ME (CNM); 6) PD treated with ME (PDM); 7) PNX treated with ME(PNXM); 8) PNX and PD treated with ME(PNXPDM). The PNX groups were subjected to pinealectomy at 40 and at 60 days of age. The animals were then subjected to PD induction in the mandibular first molars. After PD induction, the ME replacement therapy (MERT-5 mg/kg body weight) was performed using water for 28 days. After this period, the plasma concentration of glucose, insulin, TNF, IL-6, triglycerides, total cholesterol, HDL-cholesterol, LDL-cholesterol, and VLDL-cholesterol and the HOMA-IR index were determined. Akt serine phosphorylation status in the white adipose tissue, gastrocnemius muscle, and rat liver were also evaluated. KEY FINDINGS PD, PNX, and PNXPD groups showed an increase in IR with elevated plasma levels of insulin and TNF compared to CN group. PNX and PNXPD groups presented alteration in lipid profile compared to CN group. MERT improved all of the analyzed parameters. No difference was observed in the IS among different groups. SIGNIFICANCE The results suggest that MERT efficiently prevents IR, improves lipid profile, and increases plasma levels of insulin and TNF in PD and PNX rats.
Collapse
Affiliation(s)
- Rodrigo Martins Dos Santos
- Programa de Pós-graduação Multicêntrico em Ciências Fisiológicas-SBFis, Brazil; Department of Basic Sciences, School of Dentistry of Araçatuba, São Paulo State University (UNESP), Araçatuba, SP, Brazil
| | - Fernando Marani
- Programa de Pós-graduação Multicêntrico em Ciências Fisiológicas-SBFis, Brazil; Department of Basic Sciences, School of Dentistry of Araçatuba, São Paulo State University (UNESP), Araçatuba, SP, Brazil
| | - Fernando Yamamoto Chiba
- Preventive and Social Dentistry Post-Graduation Program School of Dentistry of Araçatuba, São Paulo State University (UNESP), Araçatuba, SP, Brazil
| | - Maria Sara de Lima Coutinho Mattera
- Programa de Pós-graduação Multicêntrico em Ciências Fisiológicas-SBFis, Brazil; Department of Basic Sciences, School of Dentistry of Araçatuba, São Paulo State University (UNESP), Araçatuba, SP, Brazil
| | - Thais Verônica Saori Tsosura
- Programa de Pós-graduação Multicêntrico em Ciências Fisiológicas-SBFis, Brazil; Department of Basic Sciences, School of Dentistry of Araçatuba, São Paulo State University (UNESP), Araçatuba, SP, Brazil
| | - Gestter Willian Lattari Tessarin
- Department of Basic Sciences, School of Dentistry of Araçatuba, São Paulo State University (UNESP), Araçatuba, SP, Brazil; Institute of Biosciences of Botucatu, São Paulo State University, Botucatu, São Paulo, Brazil
| | - Renato Felipe Pereira
- Programa de Pós-graduação Multicêntrico em Ciências Fisiológicas-SBFis, Brazil; Department of Basic Sciences, School of Dentistry of Araçatuba, São Paulo State University (UNESP), Araçatuba, SP, Brazil
| | - Bianca Elvira Belardi
- Department of Basic Sciences, School of Dentistry of Araçatuba, São Paulo State University (UNESP), Araçatuba, SP, Brazil
| | - Beatriz Costa E Silva Pinheiro
- Department of Basic Sciences, School of Dentistry of Araçatuba, São Paulo State University (UNESP), Araçatuba, SP, Brazil
| | - Doris Hissako Sumida
- Programa de Pós-graduação Multicêntrico em Ciências Fisiológicas-SBFis, Brazil; Department of Basic Sciences, School of Dentistry of Araçatuba, São Paulo State University (UNESP), Araçatuba, SP, Brazil.
| |
Collapse
|
27
|
Juhola H, Postila PA, Rissanen S, Lolicato F, Vattulainen I, Róg T. Negatively Charged Gangliosides Promote Membrane Association of Amphipathic Neurotransmitters. Neuroscience 2018; 384:214-223. [DOI: 10.1016/j.neuroscience.2018.05.035] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Revised: 05/21/2018] [Accepted: 05/22/2018] [Indexed: 01/09/2023]
|
28
|
Peters BJ, Van Cleave C, Haase AA, Hough JPB, Giffen-Kent KA, Cardiff GM, Sostarecz AG, Crick DC, Crans DC. Structure Dependence of Pyridine and Benzene Derivatives on Interactions with Model Membranes. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:8939-8951. [PMID: 29958493 PMCID: PMC6106790 DOI: 10.1021/acs.langmuir.8b01661] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Pyridine-based small-molecule drugs, vitamins, and cofactors are vital for many cellular processes, but little is known about their interactions with membrane interfaces. These specific membrane interactions of these small molecules or ions can assist in diffusion across membranes or reach a membrane-bound target. This study explores how minor differences in small molecules (isoniazid, benzhydrazide, isonicotinamide, nicotinamide, picolinamide, and benzamide) can affect their interactions with model membranes. Langmuir monolayer studies of dipalmitoylphosphatidylcholine (DPPC) or dipalmitoylphosphatidylethanolamine (DPPE), in the presence of the molecules listed, show that isoniazid and isonicotinamide affect the DPPE monolayer at lower concentrations than the DPPC monolayer, demonstrating a preference for one phospholipid over the other. The Langmuir monolayer studies also suggest that nitrogen content and stereochemistry of the small molecule can affect the phospholipid monolayers differently. To determine the molecular interactions of the simple N-containing aromatic pyridines with a membrane-like interface, 1H one-dimensional NMR and 1H-1H two-dimensional NMR techniques were utilized to obtain information about the position and orientation of the molecules of interest within aerosol-OT (AOT) reverse micelles. These studies show that all six of the molecules reside near the AOT sulfonate headgroups and ester linkages in similar positions, but nicotinamide and picolinamide tilt at the water-AOT interface to varying degrees. Combined, these studies demonstrate that small structural changes of small N-containing molecules can affect their specific interactions with membrane-like interfaces and specificity toward different membrane components.
Collapse
Affiliation(s)
| | | | | | | | | | | | - Audra G Sostarecz
- Department of Chemistry , Monmouth College , Monmouth , Illinois 61462 , United States
| | | | | |
Collapse
|
29
|
Cholesterol modulates the liposome membrane fluidity and permeability for a hydrophilic molecule. Food Chem Toxicol 2018; 113:40-48. [PMID: 29337230 DOI: 10.1016/j.fct.2018.01.017] [Citation(s) in RCA: 134] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Revised: 01/09/2018] [Accepted: 01/11/2018] [Indexed: 01/27/2023]
Abstract
The effect of cholesterol (CHOL) content on the permeability and fluidity of dipalmitoylphosphatidylcholine (DPPC) liposome membrane was investigated. Liposomes encapsulating sulforhodamine B (SRB), a fluorescent dye, were prepared by reverse phase evaporation technique (REV) at various DPPC:CHOL molar ratios (from 100:0 to 100:100). The release kinetics of SRB was studied during 48 h in buffer (pH 7.4) containing NaCl at 37 °C. The DPPC:CHOL formulations were also characterized for their size, polydispersity index and morphology. Increasing CHOL concentration induced an increase in the mean liposomes size accompanying with a shape transition from irregular to nanosized, regular and spherical vesicles. The release kinetics of SRB showed a biphasic pattern; the release data was then analyzed using different mathematical models. On the overall, the SRB release was governed by a non-Fickian diffusion during the first period (0-10 h) while it followed a Fickian diffusion between 10 and 48 h. Changes in DPPC liposome membrane fluidity of various batches (CHOL% 0, 10, 20, 30 and 100) were monitored by using 5- and 16 doxyl stearic acids (DSA) as spin labels. CHOL induced a decrease in the bilayer fluidity. Concisely, CHOL represents a critical component in modulating the release of hydrophilic molecules from lipid vesicles.
Collapse
|
30
|
Koehn J, Magallanes ES, Peters BJ, Beuning CN, Haase AA, Zhu MJ, Rithner CD, Crick DC, Crans DC. A Synthetic Isoprenoid Lipoquinone, Menaquinone-2, Adopts a Folded Conformation in Solution and at a Model Membrane Interface. J Org Chem 2018; 83:275-288. [PMID: 29168636 PMCID: PMC5759649 DOI: 10.1021/acs.joc.7b02649] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Indexed: 11/29/2022]
Abstract
Menaquinones (naphthoquinones, MK) are isoprenoids that play key roles in the respiratory electron transport system of some prokaryotes by shuttling electrons between membrane-bound protein complexes acting as electron acceptors and donors. Menaquinone-2 (MK-2), a truncated MK, was synthesized, and the studies presented herein characterize the conformational and chemical properties of the hydrophobic MK-2 molecule. Using 2D NMR spectroscopy, we established for the first time that MK-2 has a folded conformation defined by the isoprenyl side-chain folding back over the napthoquinone in a U-shape, which depends on the specific environmental conditions found in different solvents. We used molecular mechanics to illustrate conformations found by the NMR experiments. The measured redox potentials of MK-2 differed in three organic solvents, where MK-2 was most easily reduced in DMSO, which may suggest a combination of solvent effect (presumably in part because of differences in dielectric constants) and/or conformational differences of MK-2 in different organic solvents. Furthermore, MK-2 was found to associate with the interface of model membranes represented by Langmuir phospholipid monolayers and Aerosol-OT (AOT) reverse micelles. MK-2 adopts a slightly different U-shaped conformation within reverse micelles compared to within solution, which is in sharp contrast to the extended conformations illustrated in literature for MKs.
Collapse
Affiliation(s)
- Jordan
T. Koehn
- Chemistry
Department, Cell and Molecular Biology Program,
and Microbiology, Immunology,
and Pathology Department, Colorado State
University, Fort Collins, Colorado 80523, United States
| | - Estela S. Magallanes
- Chemistry
Department, Cell and Molecular Biology Program,
and Microbiology, Immunology,
and Pathology Department, Colorado State
University, Fort Collins, Colorado 80523, United States
| | - Benjamin J. Peters
- Chemistry
Department, Cell and Molecular Biology Program,
and Microbiology, Immunology,
and Pathology Department, Colorado State
University, Fort Collins, Colorado 80523, United States
| | - Cheryle N. Beuning
- Chemistry
Department, Cell and Molecular Biology Program,
and Microbiology, Immunology,
and Pathology Department, Colorado State
University, Fort Collins, Colorado 80523, United States
| | - Allison A. Haase
- Chemistry
Department, Cell and Molecular Biology Program,
and Microbiology, Immunology,
and Pathology Department, Colorado State
University, Fort Collins, Colorado 80523, United States
| | - Michelle J. Zhu
- Chemistry
Department, Cell and Molecular Biology Program,
and Microbiology, Immunology,
and Pathology Department, Colorado State
University, Fort Collins, Colorado 80523, United States
| | - Christopher D. Rithner
- Chemistry
Department, Cell and Molecular Biology Program,
and Microbiology, Immunology,
and Pathology Department, Colorado State
University, Fort Collins, Colorado 80523, United States
| | - Dean C. Crick
- Chemistry
Department, Cell and Molecular Biology Program,
and Microbiology, Immunology,
and Pathology Department, Colorado State
University, Fort Collins, Colorado 80523, United States
| | - Debbie C. Crans
- Chemistry
Department, Cell and Molecular Biology Program,
and Microbiology, Immunology,
and Pathology Department, Colorado State
University, Fort Collins, Colorado 80523, United States
| |
Collapse
|
31
|
Chen LY, Renn TY, Liao WC, Mai FD, Ho YJ, Hsiao G, Lee AW, Chang HM. Melatonin successfully rescues hippocampal bioenergetics and improves cognitive function following drug intoxication by promoting Nrf2-ARE signaling activity. J Pineal Res 2017; 63. [PMID: 28480587 DOI: 10.1111/jpi.12417] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Accepted: 05/02/2017] [Indexed: 12/25/2022]
Abstract
Prolonged exposure to gamma-hydroxybutyric acid (GHB) would cause drug intoxication in which impaired cognitive function results from enhanced hippocampal oxidative stress may serve as a major symptom in this deficiency. Considering melatonin possesses significant anti-oxidative efficacy, this study aimed to determine whether melatonin would successfully promote the nuclear factor erythroid 2-related factor 2 and antioxidant responsive element (Nrf2-ARE) signaling, depress oxidative stress, and rescue hippocampal bioenergetics and cognitive function following drug intoxication injury. Adolescent rats subjected to 10 days of GHB were received melatonin at doses of either 10 or 100 mg/kg. Time-of-flight secondary ion mass spectrometry, biochemical assay, quantitative histochemistry, [14 C]-2-deoxyglucose analysis, together with Morris water maze were employed to detect the molecular signaling, oxidative status, bioenergetic level, as well as the cognitive performances, respectively. Results indicated that in GHB-intoxicated rats, enhanced oxidative stress, increased cholesterol level, and decreased anti-oxidative enzymes activities were detected in hippocampal regions. Intense oxidative stress paralleled well with reduced bioenergetics and poor performance in behavioral testing. However, in rats treated with melatonin following GHB intoxication, all above parameters and cognitive function were gradually returned to nearly normal levels. Melatonin also remarkably promoted the translocation of Nrf2 from cytoplasm to nucleus in a dose-dependent manner, thereby increased the Nrf2-ARE signaling-related downstream anti-oxidative enzymes activities. As melatonin effectively rescues hippocampal bioenergetics through depressing the oxidative stress by promoting Nrf2-ARE molecular machinery, this study thus highlights for the first time that clinical use of melatonin may serve as a therapeutic strategy to improve the cognitive function in unsuspecting victims suffered from GHB intoxication injury.
Collapse
Affiliation(s)
- Li-You Chen
- Department of Anatomy, School of Medicine, College of Medicine, Chung Shan Medical University, Taichung, Taiwan
- Department of Medical Education, Chung Shan Medical University Hospital, Taichung, Taiwan
| | - Ting-Yi Renn
- Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Wen-Chieh Liao
- Department of Anatomy, School of Medicine, College of Medicine, Chung Shan Medical University, Taichung, Taiwan
| | - Fu-Der Mai
- Department of Biochemistry and Molecular Cell Biology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Ying-Jui Ho
- School of Psychology, College of Medical Science and Technology, Chung Shan Medical University, Taichung, Taiwan
| | - George Hsiao
- Department of Pharmacology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Ai-Wei Lee
- Department of Anatomy and Cell Biology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Hung-Ming Chang
- Department of Anatomy and Cell Biology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| |
Collapse
|
32
|
Mokkila S, Postila PA, Rissanen S, Juhola H, Vattulainen I, Róg T. Calcium Assists Dopamine Release by Preventing Aggregation on the Inner Leaflet of Presynaptic Vesicles. ACS Chem Neurosci 2017; 8:1242-1250. [PMID: 28165217 DOI: 10.1021/acschemneuro.6b00395] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
In this study, the dopamine-lipid bilayer interactions were probed with three physiologically relevant ion compositions using atomistic molecular dynamics simulations and free energy calculations. The in silico results indicate that calcium is able to decrease significantly the binding of dopamine to a neutral (zwitterionic) phosphatidylcholine lipid bilayer model mimicking the inner leaflet of a presynaptic vesicle. We argue that the observed calcium-induced effect is likely in crucial role in the neurotransmitter release from the presynaptic vesicles docked in the active zone of nerve terminals. The inner leaflets of presynaptic vesicles, which are responsible for releasing neurotransmitters into the synaptic cleft, are mainly composed of neutral lipids such as phosphatidylcholine and phosphatidylethanolamine. The neutrality of the lipid head group region, enhanced by a low pH level, should limit membrane aggregation of transmitters. In addition, the simulations suggest that the high calcium levels inside presynaptic vesicles prevent even the most lipophilic transmitters such as dopamine from adhering to the inner leaflet surface, thus rendering unhindered neurotransmitter release feasible.
Collapse
Affiliation(s)
- Sini Mokkila
- Department of Physics, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere, Finland
| | - Pekka A. Postila
- Structural Bioinformatics Laboratory, Biochemistry,
Faculty of Science and Engineering, Åbo Akademi University, 20500 Turku, Finland
| | - Sami Rissanen
- Department of Physics, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere, Finland
| | - Hanna Juhola
- Department of Physics, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere, Finland
| | - Ilpo Vattulainen
- Department of Physics, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere, Finland
- Department of Physics, University of Helsinki, P.O. Box 64, FI-00014 Helsinki, Finland
- MEMPHYS − Center for Biomembrane
Physics, University of Southern Denmark, 5230 Odense, Denmark
| | - Tomasz Róg
- Department of Physics, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere, Finland
- Department of Physics, University of Helsinki, P.O. Box 64, FI-00014 Helsinki, Finland
| |
Collapse
|
33
|
A Biocompatible Synthetic Lung Fluid Based on Human Respiratory Tract Lining Fluid Composition. Pharm Res 2017; 34:2454-2465. [PMID: 28560698 PMCID: PMC5736781 DOI: 10.1007/s11095-017-2169-4] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Accepted: 04/27/2017] [Indexed: 11/03/2022]
Abstract
PURPOSE To characterise a biorelevant simulated lung fluid (SLF) based on the composition of human respiratory tract lining fluid. SLF was compared to other media which have been utilized as lung fluid simulants in terms of fluid structure, biocompatibility and performance in inhalation biopharmaceutical assays. METHODS The structure of SLF was investigated using cryo-transmission electron microscopy, photon correlation spectroscopy and Langmuir isotherms. Biocompatibility with A549 alveolar epithelial cells was determined by MTT assay, morphometric observations and transcriptomic analysis. Biopharmaceutical applicability was evaluated by measuring the solubility and dissolution of beclomethasone dipropionate (BDP) and fluticasone propionate (FP), in SLF. RESULTS SLF exhibited a colloidal structure, possessing vesicles similar in nature to those found in lung fluid extracts. No adverse effect on A549 cells was apparent after exposure to the SLF for 24 h, although some metabolic changes were identified consistent with the change of culture medium to a more lung-like composition. The solubility and dissolution of BDP and FP in SLF were enhanced compared to Gamble's solution. CONCLUSION The SLF reported herein constitutes a biorelevant synthetic simulant which is suitable to study biopharmaceutical properties of inhalation medicines such as those being proposed for an inhaled biopharmaceutics classification system.
Collapse
|
34
|
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]
|
35
|
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
|
36
|
Alsop RJ, Toppozini L, Marquardt D, Kučerka N, Harroun TA, Rheinstädter MC. Aspirin inhibits formation of cholesterol rafts in fluid lipid membranes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2015; 1848:805-12. [DOI: 10.1016/j.bbamem.2014.11.023] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2014] [Revised: 11/18/2014] [Accepted: 11/19/2014] [Indexed: 12/20/2022]
|
37
|
Dies H, Cheung B, Tang J, Rheinstädter MC. The organization of melatonin in lipid membranes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2015; 1848:1032-40. [PMID: 25602914 DOI: 10.1016/j.bbamem.2015.01.006] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2014] [Revised: 12/29/2014] [Accepted: 01/10/2015] [Indexed: 12/21/2022]
Abstract
Melatonin is a hormone that has been shown to have protective effects in several diseases that are associated with cholesterol dysregulation, including cardiovascular disease, Alzheimer's disease, and certain types of cancers. We studied the interaction of melatonin with model membranes made of dimyristoylphosphatidylcholine (DMPC) at melatonin concentrations ranging from 0.5mol% to 30mol%. From 2-dimensional X-ray diffraction measurements, we find that melatonin induces a re-ordering of the lipid membrane that is strongly dependent on the melatonin concentration. At low melatonin concentrations, we observe the presence of melatonin-enriched patches in the membrane, which are significantly thinner than the lipid bilayer. The melatonin molecules were found to align parallel to the lipid tails in these patches. At high melatonin concentrations of 30mol%, we observe a highly ordered melatonin structure that is uniform throughout the membrane, where the melatonin molecules align parallel to the bilayers and one melatonin molecule associates with 2 lipid molecules. Understanding the organization and interactions of melatonin in membranes, and how these are dependent on the concentration, may shed light into its anti-amyloidogenic, antioxidative and photoprotective properties and help develop a structural basis for these properties.
Collapse
Affiliation(s)
- Hannah Dies
- Department of Physics and Astronomy, McMaster University, Hamilton, Ontario Canada.
| | - Bonnie Cheung
- Department of Physics and Astronomy, McMaster University, Hamilton, Ontario Canada
| | - Jennifer Tang
- Department of Physics and Astronomy, McMaster University, Hamilton, Ontario Canada
| | | |
Collapse
|
38
|
Róg T, Vattulainen I. Cholesterol, sphingolipids, and glycolipids: what do we know about their role in raft-like membranes? Chem Phys Lipids 2014; 184:82-104. [PMID: 25444976 DOI: 10.1016/j.chemphyslip.2014.10.004] [Citation(s) in RCA: 140] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2014] [Revised: 10/24/2014] [Accepted: 10/25/2014] [Indexed: 12/14/2022]
Abstract
Lipids rafts are considered to be functional nanoscale membrane domains enriched in cholesterol and sphingolipids, characteristic in particular of the external leaflet of cell membranes. Lipids, together with membrane-associated proteins, are therefore considered to form nanoscale units with potential specific functions. Although the understanding of the structure of rafts in living cells is quite limited, the possible functions of rafts are widely discussed in the literature, highlighting their importance in cellular functions. In this review, we discuss the understanding of rafts that has emerged based on recent atomistic and coarse-grained molecular dynamics simulation studies on the key lipid raft components, which include cholesterol, sphingolipids, glycolipids, and the proteins interacting with these classes of lipids. The simulation results are compared to experiments when possible.
Collapse
Affiliation(s)
- Tomasz Róg
- Department of Physics, Tampere University of Technology, Tampere, Finland
| | - Ilpo Vattulainen
- Department of Physics, Tampere University of Technology, Tampere, Finland; MEMPHYS-Center for Biomembrane Physics, University of Southern Denmark, Odense, Denmark.
| |
Collapse
|