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Jobin ML, De Smedt-Peyrusse V, Ducrocq F, Baccouch R, Oummadi A, Pedersen MH, Medel-Lacruz B, Angelo MF, Villette S, Van Delft P, Fouillen L, Mongrand S, Selent J, Tolentino-Cortez T, Barreda-Gómez G, Grégoire S, Masson E, Durroux T, Javitch JA, Guixà-González R, Alves ID, Trifilieff P. Impact of membrane lipid polyunsaturation on dopamine D2 receptor ligand binding and signaling. Mol Psychiatry 2023; 28:1960-1969. [PMID: 36604603 DOI: 10.1038/s41380-022-01928-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 12/05/2022] [Accepted: 12/14/2022] [Indexed: 01/07/2023]
Abstract
Increasing evidence supports a relationship between lipid metabolism and mental health. In particular, the biostatus of polyunsaturated fatty acids (PUFAs) correlates with some symptoms of psychiatric disorders, as well as the efficacy of pharmacological treatments. Recent findings highlight a direct association between brain PUFA levels and dopamine transmission, a major neuromodulatory system implicated in the etiology of psychiatric symptoms. However, the mechanisms underlying this relationship are still unknown. Here we demonstrate that membrane enrichment in the n-3 PUFA docosahexaenoic acid (DHA), potentiates ligand binding to the dopamine D2 receptor (D2R), suggesting that DHA acts as an allosteric modulator of this receptor. Molecular dynamics simulations confirm that DHA has a high preference for interaction with the D2R and show that membrane unsaturation selectively enhances the conformational dynamics of the receptor around its second intracellular loop. We find that membrane unsaturation spares G protein activity but potentiates the recruitment of β-arrestin in cells. Furthermore, in vivo n-3 PUFA deficiency blunts the behavioral effects of two D2R ligands, quinpirole and aripiprazole. These results highlight the importance of membrane unsaturation for D2R activity and provide a putative mechanism for the ability of PUFAs to enhance antipsychotic efficacy.
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Affiliation(s)
- Marie-Lise Jobin
- Université de Bordeaux, INRAE, Bordeaux INP, NutriNeuro, 33000, Bordeaux, France
| | | | - Fabien Ducrocq
- Université de Bordeaux, INRAE, Bordeaux INP, NutriNeuro, 33000, Bordeaux, France
| | - Rim Baccouch
- Institute of Chemistry & Biology of Membranes & Nanoobjects, CNRS UMR 5248, Université de Bordeaux, Bordeaux INP, 33600, Pessac, France
| | - Asma Oummadi
- Université de Bordeaux, INRAE, Bordeaux INP, NutriNeuro, 33000, Bordeaux, France
| | - Maria Hauge Pedersen
- Department of Psychiatry, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, 10032, USA
- Division of Molecular Therapeutics, New York State Psychiatric Institute, New York, NY, 10032, USA
| | - Brian Medel-Lacruz
- Research Programme on Biomedical Informatics (GRIB), Hospital del Mar Medical Research Institute (IMIM)-Department of Experimental and Health Sciences, Pompeu Fabra University (UPF), 08003, Barcelona, Spain
| | | | - Sandrine Villette
- Institute of Chemistry & Biology of Membranes & Nanoobjects, CNRS UMR 5248, Université de Bordeaux, Bordeaux INP, 33600, Pessac, France
| | - Pierre Van Delft
- Laboratory of Membrane Biogenesis (LBM), Research Mix Unity (UMR) 5200, National Scientific Research Center (CNRS), University of Bordeaux, Bordeaux, France
| | - Laetitia Fouillen
- Laboratory of Membrane Biogenesis (LBM), Research Mix Unity (UMR) 5200, National Scientific Research Center (CNRS), University of Bordeaux, Bordeaux, France
| | - Sébastien Mongrand
- Laboratory of Membrane Biogenesis (LBM), Research Mix Unity (UMR) 5200, National Scientific Research Center (CNRS), University of Bordeaux, Bordeaux, France
| | - Jana Selent
- Research Programme on Biomedical Informatics (GRIB), Hospital del Mar Medical Research Institute (IMIM)-Department of Experimental and Health Sciences, Pompeu Fabra University (UPF), 08003, Barcelona, Spain
| | | | - Gabriel Barreda-Gómez
- Research Department, IMG Pharma Biotech S.L., BIC Bizkaia (612), 48160, Derio, Spain
| | - Stéphane Grégoire
- Centre des Sciences du Goût et de l'Alimentation, AgroSup Dijon, CNRS, INRAE, Université Bourgogne Franche-Comté, 21000, Dijon, France
| | - Elodie Masson
- Centre des Sciences du Goût et de l'Alimentation, AgroSup Dijon, CNRS, INRAE, Université Bourgogne Franche-Comté, 21000, Dijon, France
| | - Thierry Durroux
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France
| | - Jonathan A Javitch
- Department of Psychiatry, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, 10032, USA
- Division of Molecular Therapeutics, New York State Psychiatric Institute, New York, NY, 10032, USA
- Department of Molecular Pharmacology and Therapeutics, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, 10032, USA
| | - Ramon Guixà-González
- Condensed Matter Theory Group, Paul Scherrer Institute (PSI), 5232, Villigen, PSI, Switzerland.
| | - Isabel D Alves
- Institute of Chemistry & Biology of Membranes & Nanoobjects, CNRS UMR 5248, Université de Bordeaux, Bordeaux INP, 33600, Pessac, France.
| | - Pierre Trifilieff
- Université de Bordeaux, INRAE, Bordeaux INP, NutriNeuro, 33000, Bordeaux, France.
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Baccouch R, Shi Y, Vernay E, Mathelié-Guinlet M, Taib-Maamar N, Villette S, Feuillie C, Rascol E, Nuss P, Lecomte S, Molinari M, Staneva G, Alves ID. The impact of lipid polyunsaturation on the physical and mechanical properties of lipid membranes. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2023; 1865:184084. [PMID: 36368636 DOI: 10.1016/j.bbamem.2022.184084] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 10/21/2022] [Accepted: 10/25/2022] [Indexed: 11/09/2022]
Abstract
The lipid composition of cellular membranes and the balance between the different lipid components can be impacted by aging, certain pathologies, specific diets and other factors. This is the case in a subgroup of individuals with psychiatric disorders, such as schizophrenia, where cell membranes of patients have been shown to be deprived in polyunsaturated fatty acids (PUFAs), not only in brain areas where the target receptors are expressed but also in peripheral tissues. This PUFA deprivation thus represents a biomarker of such disorders that might impact not only the interaction of antipsychotic medications with these membranes but also the activation and signaling of the targeted receptors embedded in the lipid membrane. Therefore, it is crucial to understand how PUFAs levels alterations modulate the different physical properties of membranes. In this paper, several biophysical approaches were combined (Laurdan fluorescence spectroscopy, atomic force microscopy, differential scanning calorimetry, molecular modeling) to characterize membrane properties such as fluidity, elasticity and thickness in PUFA-enriched cell membranes and lipid model systems reflecting the PUFA imbalance observed in some diseases. The impact of both the number of unsaturations and their position along the chain on the above properties was investigated. Briefly, data revealed that PUFA presence in membranes increases membrane fluidity, elasticity and flexibility and decreases its thickness and order parameter. Both the level of unsaturation and their position affect these membrane properties.
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Affiliation(s)
- Rim Baccouch
- Univ. Bordeaux, CNRS, Bordeaux INP, CBMN, UMR 5248, Bat B14, allée Geoffroy St. Hilaire, F-33600 Pessac, France
| | - Yarong Shi
- Laboratoire de Recherche en Nanosciences, LRN EA4682, University of Reims Champagne Ardenne, France
| | - Emilie Vernay
- Univ. Bordeaux, CNRS, Bordeaux INP, CBMN, UMR 5248, Bat B14, allée Geoffroy St. Hilaire, F-33600 Pessac, France
| | - Marion Mathelié-Guinlet
- Univ. Bordeaux, CNRS, Bordeaux INP, CBMN, UMR 5248, Bat B14, allée Geoffroy St. Hilaire, F-33600 Pessac, France
| | - Nada Taib-Maamar
- Univ. Bordeaux, CNRS, Bordeaux INP, CBMN, UMR 5248, Bat B14, allée Geoffroy St. Hilaire, F-33600 Pessac, France
| | - Sandrine Villette
- Univ. Bordeaux, CNRS, Bordeaux INP, CBMN, UMR 5248, Bat B14, allée Geoffroy St. Hilaire, F-33600 Pessac, France
| | - Cécile Feuillie
- Univ. Bordeaux, CNRS, Bordeaux INP, CBMN, UMR 5248, Bat B14, allée Geoffroy St. Hilaire, F-33600 Pessac, France
| | - Estelle Rascol
- Univ. Bordeaux, CNRS, Bordeaux INP, CBMN, UMR 5248, Bat B14, allée Geoffroy St. Hilaire, F-33600 Pessac, France
| | - Philippe Nuss
- Centre de Recherche Saint-Antoine, INSERM UMRS 938, Sorbonne Université, Paris, France; Service de psychiatrie et de psychologie médicale, Sorbonne Université, Hôpital Saint-Antoine, AP-HP, Paris, France
| | - Sophie Lecomte
- Univ. Bordeaux, CNRS, Bordeaux INP, CBMN, UMR 5248, Bat B14, allée Geoffroy St. Hilaire, F-33600 Pessac, France
| | - Michael Molinari
- Univ. Bordeaux, CNRS, Bordeaux INP, CBMN, UMR 5248, Bat B14, allée Geoffroy St. Hilaire, F-33600 Pessac, France
| | - Galya Staneva
- Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl.21, 1113 Sofia, Bulgaria
| | - Isabel D Alves
- Univ. Bordeaux, CNRS, Bordeaux INP, CBMN, UMR 5248, Bat B14, allée Geoffroy St. Hilaire, F-33600 Pessac, France.
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Falcón-González JM, Cantú-Cárdenas LG, García-González A, Carrillo-Tripp M. Differences in the local anaesthesia effect by lidocaine and bupivacaine based on free energy analysis. MOLECULAR SIMULATION 2022. [DOI: 10.1080/08927022.2022.2053118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- José Marcos Falcón-González
- Unidad Profesional Interdisciplinaria de Ingeniería Campus Guanajuato, Instituto Politécnico Nacional, Silao de la Victoria, Guanajuato, México
| | - Lucía Guadalupe Cantú-Cárdenas
- Facultad de Ciencias Químicas, Laboratorio de Fisicoquímica de Interfases, Universidad Autónoma de Nuevo León, San Nicolás de los Garza, NL, México
| | - Alcione García-González
- Facultad de Ciencias Químicas, Laboratorio de Fisicoquímica de Interfases, Universidad Autónoma de Nuevo León, San Nicolás de los Garza, NL, México
| | - Mauricio Carrillo-Tripp
- Biomolecular Diversity Laboratory, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional Unidad Monterrey, Apodaca, Nuevo León, México
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Grage SL, Culetto A, Ulrich AS, Weinschenk S. Membrane-Mediated Activity of Local Anesthetics. Mol Pharmacol 2021; 100:502-512. [PMID: 34475108 DOI: 10.1124/molpharm.121.000252] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 07/19/2021] [Indexed: 01/06/2023] Open
Abstract
The activity of local anesthetics (LAs) has been attributed to the inhibition of ion channels, causing anesthesia. However, there is a growing body of research showing that LAs act on a wide range of receptors and channel proteins far beyond simple analgesia. The current concept of ligand recognition may no longer explain the multitude of protein targets influenced by LAs. We hypothesize that LAs can cause anesthesia without directly binding to the receptor proteins just by changing the physical properties of the lipid bilayer surrounding these proteins and ion channels based on LAs' amphiphilicity. It is possible that LAs act in one of the following ways: They 1) dissolve raft-like membrane microdomains, 2) impede nerve impulse propagation by lowering the lipid phase transition temperature, or 3) modulate the lateral pressure profile of the lipid bilayer. This could also explain the numerous additional effects of LAs besides anesthesia. Furthermore, the concepts of membrane-mediated activity and binding to ion channels do not have to exclude each other. If we were to consider LA as the middle part of a continuum between unspecific membrane-mediated activity on one end and highly specific ligand binding on the other end, we could describe LA as the link between the unspecific action of general anesthetics and toxins with their highly specific receptor binding. This comprehensive membrane-mediated model offers a fresh perspective to clinical and pharmaceutical research and therapeutic applications of local anesthetics. SIGNIFICANCE STATEMENT: Local anesthetics, according to the World Health Organization, belong to the most important drugs available to mankind. Their rediscovery as therapeutics and not only anesthetics marks a milestone in global pain therapy. The membrane-mediated mechanism of action proposed in this review can explain their puzzling variety of target proteins and their thus far inexplicable therapeutic effects. The new concept presented here places LAs on a continuum of structures and molecular mechanisms in between small general anesthetics and the more complex molecular toxins.
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Affiliation(s)
- Stephan L Grage
- Institute of Biological Interfaces (IBG-2), Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany (S.L.G., A.C., A.S.U.); Institute of Organic Chemistry, KIT, Karlsruhe, Germany (A.C., A.S.U.); Women's Hospital, Department of Gynecological Endocrinology and Fertility Disorders, Heidelberg, Germany (S.W.); and The HUNTER Group, Heidelberg University, Women's Hospital, Im Neuenheimer Feld 440, 69120 Heidelberg, Germany, Heidelberg University, Women's Hospital, Neural Therapy Education & Research Group (S.W.)
| | - Anke Culetto
- Institute of Biological Interfaces (IBG-2), Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany (S.L.G., A.C., A.S.U.); Institute of Organic Chemistry, KIT, Karlsruhe, Germany (A.C., A.S.U.); Women's Hospital, Department of Gynecological Endocrinology and Fertility Disorders, Heidelberg, Germany (S.W.); and The HUNTER Group, Heidelberg University, Women's Hospital, Im Neuenheimer Feld 440, 69120 Heidelberg, Germany, Heidelberg University, Women's Hospital, Neural Therapy Education & Research Group (S.W.)
| | - Anne S Ulrich
- Institute of Biological Interfaces (IBG-2), Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany (S.L.G., A.C., A.S.U.); Institute of Organic Chemistry, KIT, Karlsruhe, Germany (A.C., A.S.U.); Women's Hospital, Department of Gynecological Endocrinology and Fertility Disorders, Heidelberg, Germany (S.W.); and The HUNTER Group, Heidelberg University, Women's Hospital, Im Neuenheimer Feld 440, 69120 Heidelberg, Germany, Heidelberg University, Women's Hospital, Neural Therapy Education & Research Group (S.W.)
| | - Stefan Weinschenk
- Institute of Biological Interfaces (IBG-2), Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany (S.L.G., A.C., A.S.U.); Institute of Organic Chemistry, KIT, Karlsruhe, Germany (A.C., A.S.U.); Women's Hospital, Department of Gynecological Endocrinology and Fertility Disorders, Heidelberg, Germany (S.W.); and The HUNTER Group, Heidelberg University, Women's Hospital, Im Neuenheimer Feld 440, 69120 Heidelberg, Germany, Heidelberg University, Women's Hospital, Neural Therapy Education & Research Group (S.W.)
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5
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EPA and DHA differentially modulate membrane elasticity in the presence of cholesterol. Biophys J 2021; 120:2317-2329. [PMID: 33887229 PMCID: PMC8390804 DOI: 10.1016/j.bpj.2021.04.009] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2020] [Revised: 03/15/2021] [Accepted: 04/09/2021] [Indexed: 12/16/2022] Open
Abstract
Polyunsaturated fatty acids (PUFAs) modify the activity of a wide range of membrane proteins and are increasingly hypothesized to modulate protein activity by indirectly altering membrane physical properties. Among the various physical properties affected by PUFAs, the membrane area expansion modulus (Ka), which measures membrane strain in response to applied force, is expected to be a significant controller of channel activity. Yet, the impact of PUFAs on membrane Ka has not been measured previously. Through a series of micropipette aspiration studies, we measured the apparent Ka (Kapp) of phospholipid model membranes containing nonesterified fatty acids. First, we measured membrane Kapp as a function of the location of the unsaturated bonds and degree of unsaturation in the incorporated fatty acids and found that Kapp generally decreases in the presence of fatty acids with three or more unsaturated bonds. Next, we assessed how select ω-3 PUFAs, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), affect the Kapp of membranes containing cholesterol. In vesicles prepared with high amounts of cholesterol, which should increase the propensity of the membrane to phase segregate, we found that inclusion of DHA decreases the Kapp in comparison to EPA. We also measured how these ω-3 PUFAs affect membrane fluidity and bending rigidity to determine how membrane Kapp changes in relation to these other physical properties. Our study shows that PUFAs generally decrease the Kapp of membranes and that EPA and DHA have differential effects on Kapp when membranes contain higher levels of cholesterol. Our results suggest membrane phase behavior and the distribution of membrane-elasticizing amphiphiles impact the ability of a membrane to stretch.
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Pal A, Metherel AH, Fiabane L, Buddenbaum N, Bazinet RP, Shaikh SR. Do Eicosapentaenoic Acid and Docosahexaenoic Acid Have the Potential to Compete against Each Other? Nutrients 2020; 12:nu12123718. [PMID: 33276463 PMCID: PMC7760937 DOI: 10.3390/nu12123718] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 11/23/2020] [Accepted: 11/28/2020] [Indexed: 12/15/2022] Open
Abstract
Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are n-3 polyunsaturated fatty acids (PUFAs) consumed in low abundance in the Western diet. Increased consumption of n-3 PUFAs may have beneficial effects for a wide range of physiological outcomes including chronic inflammation. However, considerable mechanistic gaps in knowledge exist about EPA versus DHA, which are often studied as a mixture. We suggest the novel hypothesis that EPA and DHA may compete against each other through overlapping mechanisms. First, EPA and DHA may compete for residency in membrane phospholipids and thereby differentially displace n-6 PUFAs, which are highly prevalent in the Western diet. This would influence biosynthesis of downstream metabolites of inflammation initiation and resolution. Second, EPA and DHA exert different effects on plasma membrane biophysical structure, creating an additional layer of competition between the fatty acids in controlling signaling. Third, DHA regulates membrane EPA levels by lowering its rate of conversion to EPA's elongation product n-3 docosapentaenoic acid. Collectively, we propose the critical need to investigate molecular competition between EPA and DHA in health and disease, which would ultimately impact dietary recommendations and precision nutrition trials.
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Affiliation(s)
- Anandita Pal
- Department of Nutrition, Gillings School of Global Public Health and School of Medicine, The University of North Carolina at Chapel Hill, 170 Rosenau Hall, CB# 7400, 135 Dauer Drive, Chapel Hill, NC 27516, USA; (A.P.); (L.F.); (N.B.)
| | - Adam H. Metherel
- Department of Nutritional Sciences, Medical Sciences Building, 5th Floor, Room 5358, University of Toronto, 1 King’s College Circle, Toronto, ON M5S 1A8, Canada; (A.H.M.); (R.P.B.)
| | - Lauren Fiabane
- Department of Nutrition, Gillings School of Global Public Health and School of Medicine, The University of North Carolina at Chapel Hill, 170 Rosenau Hall, CB# 7400, 135 Dauer Drive, Chapel Hill, NC 27516, USA; (A.P.); (L.F.); (N.B.)
| | - Nicole Buddenbaum
- Department of Nutrition, Gillings School of Global Public Health and School of Medicine, The University of North Carolina at Chapel Hill, 170 Rosenau Hall, CB# 7400, 135 Dauer Drive, Chapel Hill, NC 27516, USA; (A.P.); (L.F.); (N.B.)
| | - Richard P. Bazinet
- Department of Nutritional Sciences, Medical Sciences Building, 5th Floor, Room 5358, University of Toronto, 1 King’s College Circle, Toronto, ON M5S 1A8, Canada; (A.H.M.); (R.P.B.)
| | - Saame Raza Shaikh
- Department of Nutrition, Gillings School of Global Public Health and School of Medicine, The University of North Carolina at Chapel Hill, 170 Rosenau Hall, CB# 7400, 135 Dauer Drive, Chapel Hill, NC 27516, USA; (A.P.); (L.F.); (N.B.)
- Correspondence: ; Tel.: +1-919-843-4348
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Harayama T, Shimizu T. Roles of polyunsaturated fatty acids, from mediators to membranes. J Lipid Res 2020; 61:1150-1160. [PMID: 32487545 PMCID: PMC7397749 DOI: 10.1194/jlr.r120000800] [Citation(s) in RCA: 72] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 05/28/2020] [Indexed: 12/20/2022] Open
Abstract
PUFAs, such as AA and DHA, are recognized as important biomolecules, but understanding their precise roles and modes of action remains challenging. PUFAs are precursors for a plethora of signaling lipids, for which knowledge about synthetic pathways and receptors has accumulated. However, due to their extreme diversity and the ambiguity concerning the identity of their cognate receptors, the roles of PUFA-derived signaling lipids require more investigation. In addition, PUFA functions cannot be explained just as lipid mediator precursors because they are also critical for the regulation of membrane biophysical properties. The presence of PUFAs in membrane lipids also affects the functions of transmembrane proteins and peripheral membrane proteins. Although the roles of PUFAs as membrane lipid building blocks were difficult to analyze, the discovery of lysophospholipid acyltransferases (LPLATs), which are critical for their incorporation, advanced our understanding. Recent studies unveiled how LPLATs affect PUFA levels in membrane lipids, and their genetic manipulation became an excellent strategy to study the roles of PUFA-containing lipids. In this review, we will provide an overview of metabolic pathways regulating PUFAs as lipid mediator precursors and membrane components and update recent progress about their functions. Some issues to be solved for future research will also be discussed.
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Affiliation(s)
- Takeshi Harayama
- Department of Biochemistry and National Centre of Competence in Research in Chemical Biology, University of Geneva, CH-1211 Geneva, Switzerland
| | - Takao Shimizu
- Department of Lipid Signaling, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo 162-8655, Japan and Department of Lipidomics, Graduate School of Medicine, University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
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Leonard AN, Wang E, Monje-Galvan V, Klauda JB. Developing and Testing of Lipid Force Fields with Applications to Modeling Cellular Membranes. Chem Rev 2019; 119:6227-6269. [DOI: 10.1021/acs.chemrev.8b00384] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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9
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Hantal G, Fábián B, Sega M, Jójárt B, Jedlovszky P. Effect of general anesthetics on the properties of lipid membranes of various compositions. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2018; 1861:594-609. [PMID: 30571949 DOI: 10.1016/j.bbamem.2018.12.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 12/05/2018] [Accepted: 12/13/2018] [Indexed: 10/27/2022]
Abstract
Computer simulations of four lipid membranes of different compositions, namely neat DPPC and PSM, and equimolar DPPC-cholesterol and PSM-cholesterol mixtures, are performed in the presence and absence of the general anesthetics diethylether and sevoflurane both at 1 and 600 bar. The results are analyzed in order to identify membrane properties that are potentially related to the molecular mechanism of anesthesia, namely that change in the same way in any membrane with any anesthetics, and change oppositely with increasing pressure. We find that the lateral lipid density satisfies both criteria: it is decreased by anesthetics and increased by pressure. This anesthetic-induced swelling is attributed to only those anesthetic molecules that are located close to the boundary of the apolar phase. This lateral expansion is found to lead to increased lateral mobility of the lipids, an effect often thought to be related to general anesthesia; to an increased fraction of the free volume around the outer preferred position of anesthetics; and to the decrease of the lateral pressure in the nearby range of the ester and amide groups, a region into which anesthetic molecules already cannot penetrate. All these changes are reverted by the increase of pressure. Another important finding of this study is that cholesterol has an opposite effect on the membrane properties than anesthetics, and, correspondingly, these changes are less marked in the presence of cholesterol. Therefore, changes in the membrane that can lead to general anesthesia are expected to occur in the membrane domains of low cholesterol content.
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Affiliation(s)
- György Hantal
- Faculty of Physics, University of Vienna, Sensengasse 8/9, A-1090 Vienna, Austria
| | - Balázs Fábián
- Department of Inorganic and Analytical Chemistry, Budapest University of Technology and Economics, Szt. Gellért tér 4, H-1111 Budapest, Hungary; Institut UTINAM (CNRS UMR 6213), Université Bourgogne Franche-Comté, 16 route de Gray, F-25030 Besançon, France
| | - Marcello Sega
- Faculty of Physics, University of Vienna, Sensengasse 8/9, A-1090 Vienna, Austria
| | - Balázs Jójárt
- Institute of Food Engineering, University of Szeged, Moszkvai krt 5-7, H-6725 Szeged, Hungary
| | - Pál Jedlovszky
- Department of Chemistry, Eszterházy Károly University, Leányka utca 6, H-3300 Eger, Hungary.
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10
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Palaiokostas M, Ding W, Shahane G, Orsi M. Effects of lipid composition on membrane permeation. SOFT MATTER 2018; 14:8496-8508. [PMID: 30346462 DOI: 10.1039/c8sm01262h] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Passive permeation through lipid membranes is an essential process in biology. In vivo membranes typically consist of mixtures of lamellar and nonlamellar lipids. Lamellar lipids are characterized by their tendency to form lamellar sheet-like structures, which are predominant in nature. Nonlamellar lipids, when isolated, instead form more geometrically complex nonlamellar phases. While mixed lamellar/nonlamellar lipid membranes tend to adopt the ubiquitous lamellar bilayer structure, the presence of nonlamellar lipids is known to have profound effects on key membrane properties, such as internal distributions of stress and elastic properties, which in turn may alter related biological processes. This work focuses on one such process, i.e., permeation, by utilising atomistic molecular dynamics simulations in order to obtain transfer free energy profiles, diffusion profiles and permeation coefficients for a series of thirteen small molecules and drugs. Each permeant is tested on two bilayer membranes of different lipid composition, i.e., purely lamellar and mixed lamellar/nonlamellar. Our results indicate that the presence of nonlamellar lipids reduces permeation for smaller molecules (molecular weight < 100) but facilitates it for the largest ones (molecular weight > 100). This work represents an advancement towards the development of more realistic in silico permeability assays, which may have a substantial future impact in the area of rational drug design.
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Affiliation(s)
- Michail Palaiokostas
- School of Engineering and Materials Science, Queen Mary University of London, London, UK
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HTMoL: full-stack solution for remote access, visualization, and analysis of molecular dynamics trajectory data. J Comput Aided Mol Des 2018; 32:869-876. [DOI: 10.1007/s10822-018-0141-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Accepted: 08/01/2018] [Indexed: 10/28/2022]
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12
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Salas-Estrada LA, Leioatts N, Romo TD, Grossfield A. Lipids Alter Rhodopsin Function via Ligand-like and Solvent-like Interactions. Biophys J 2018; 114:355-367. [PMID: 29401433 PMCID: PMC5984976 DOI: 10.1016/j.bpj.2017.11.021] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Revised: 09/20/2017] [Accepted: 11/09/2017] [Indexed: 10/18/2022] Open
Abstract
Rhodopsin, a prototypical G protein-coupled receptor, is a membrane protein that can sense dim light. This highly effective photoreceptor is known to be sensitive to the composition of its lipidic environment, but the molecular mechanisms underlying this fine-tuned modulation of the receptor's function and structural stability are not fully understood. There are two competing hypotheses to explain how this occurs: 1) lipid modulation occurs via solvent-like interactions, where lipid composition controls membrane properties like hydrophobic thickness, which in turn modulate the protein's conformational equilibrium; or 2) protein-lipid interactions are ligand-like, with specific hot spots and long-lived binding events. By analyzing an ensemble of all-atom molecular dynamics simulations of five different states of rhodopsin, we show that a local ordering effect takes place in the membrane upon receptor activation. Likewise, docosahexaenoic acid acyl tails and phosphatidylethanolamine headgroups behave like weak ligands, preferentially binding to the receptor in inactive-like conformations and inducing subtle but significant structural changes.
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Affiliation(s)
- Leslie A Salas-Estrada
- Department of Biochemistry and Biophysics, University of Rochester Medical Center, Rochester, New York
| | - Nicholas Leioatts
- Department of Theoretical and Computational Biophysics, Max Plank Institute for Biophysical Chemistry, Göttingen, Germany
| | - Tod D Romo
- Center for Integrated Research Computing, University of Rochester, Rochester, New York
| | - Alan Grossfield
- Department of Biochemistry and Biophysics, University of Rochester Medical Center, Rochester, New York.
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13
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Shahid F, Farooqui Z, Khan AA, Khan F. Oral Nigella sativa oil and thymoquinone administration ameliorates the effect of long-term cisplatin treatment on the enzymes of carbohydrate metabolism, brush border membrane, and antioxidant defense in rat intestine. Naunyn Schmiedebergs Arch Pharmacol 2018; 391:145-157. [PMID: 29302711 DOI: 10.1007/s00210-017-1444-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2017] [Accepted: 11/27/2017] [Indexed: 12/22/2022]
Abstract
We have previously shown that oral administration of Nigella sativa oil (NSO) ameliorates the deleterious gastrointestinal effects of cisplatin (CP), administered as a single dose. Since a typical clinical CP dosing regimen involves multiple cycles of CP administration in lower doses, in the present study we investigate the protective efficacy of NSO and its major bioactive constituent, thymoquinone (TQ), against multiple-dose CP treatment-induced deleterious biochemical and histological changes in rat intestine. Rats were divided into six groups, viz., control, CP, CP+NSO, CP+TQ, NSO, and TQ. Animals in CP+NSO and CP+TQ groups were pre-administered NSO (2 ml/kg bwt, orally) and TQ (1.5 mg/kg bwt, orally), respectively, daily for 14 days and were then treated with five repeated doses of CP (3 mg/kg bwt, i.p.), every fourth day for 20 days while still receiving NSO/TQ. CP treatment alone led to a significant decline in specific activities of brush border membrane (BBM) enzymes while NSO or TQ administration to CP-treated rats significantly prevented the decline in BBM enzyme activities in the isolated brush border membrane vesicles (BBMV) as well as in mucosal homogenates. Furthermore, both NSO and TQ administration markedly ameliorated CP-induced alterations on carbohydrate metabolism enzymes and the enzymatic and non-enzymatic parameters of antioxidant defense system in the intestinal mucosa. However, NSO appeared to be more efficacious than TQ in protecting against CP-induced gastrointestinal dysfunction. Histopathological findings corroborated the biochemical results. Thus, NSO and TQ may prove clinically useful in amelioration of the intestinal toxicity associated with long-term CP chemotherapy.
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Affiliation(s)
- Faaiza Shahid
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, U.P., 202002, India
| | - Zeba Farooqui
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, U.P., 202002, India
| | - Aijaz Ahmed Khan
- Department of Anatomy, Faculty of Medicine, J. N. Medical College, Aligarh Muslim University, Aligarh, U.P., 202002, India
| | - Farah Khan
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, U.P., 202002, India.
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14
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Ridone P, Grage SL, Patkunarajah A, Battle AR, Ulrich AS, Martinac B. "Force-from-lipids" gating of mechanosensitive channels modulated by PUFAs. J Mech Behav Biomed Mater 2017; 79:158-167. [PMID: 29304430 DOI: 10.1016/j.jmbbm.2017.12.026] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2017] [Revised: 12/20/2017] [Accepted: 12/22/2017] [Indexed: 12/15/2022]
Abstract
The level of fatty acid saturation in phospholipids is a crucial determinant of the biophysical properties of the lipid bilayer. Integral membrane proteins are sensitive to changes of their bilayer environment such that their activities and localization can be profoundly affected. When incorporated into phospholipids of mammalian cells, poly-unsaturated fatty acids (PUFAs) determine the mechanical properties of the bilayer thereby affecting several membrane-associated functions such as endo- and exo-cytosis and ion channel/membrane receptor signalling cascades. In order to understand how membrane tension is propagated through poly-unsaturated bilayers, we characterized the effect of lipid saturation on liposome reconstituted MscS and MscL, the two bacterial mechanosensitive ion channels that have for many years served as models of ion- channel-mediated mechanotransduction. The combination of NMR and patch clamp experiments in this study demonstrate that bilayer thinning is the main responsible factor for the modulation of the MscL threshold of activation while a change in transbilayer pressure profile is indicated as the main factor behind the observed modulation of the MscS kinetics. Together, our data offer a novel insight into how the structural shape differences between the two types of mechanosensitive channels determine their differential modulation by poly-unsaturated phospholipids and thus lay the foundation for future functional studies of eukaryotic ion channels involved in the physiology of mechanosensory transduction processes in mammalian cells. SUMMARY Mechanosensitive channels MscL and MscS are differentially modulated by poly-unsaturated fatty acids in lipid bilayers. MscL becomes sensitized because of increased hydrophobic mismatch while MscS open state is stabilized due to changes in the bilayer lateral pressure profile determined by NMR.
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Affiliation(s)
- Pietro Ridone
- Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia
| | - Stephan L Grage
- Institute for Biological Interfaces IBG-2, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Amrutha Patkunarajah
- School of Medical Sciences, University of New South Wales, Kensington, Sydney 2052, Australia
| | - Andrew R Battle
- Translational Research Institute (TRI) and Institute of Health and Biomedical Innovation (IHBI), School of Biomedical Sciences, Queensland University of Technology (QUT), Brisbane, QLD 4000, Australia
| | - Anne S Ulrich
- Institute for Biological Interfaces IBG-2, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Boris Martinac
- Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia; St Vincent's Clinical School, University of New South Wales, Darlinghurst, NSW 2010, Australia.
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15
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Falcón-González JM, Jiménez-Domínguez G, Ortega-Blake I, Carrillo-Tripp M. Multi-Phase Solvation Model for Biological Membranes: Molecular Action Mechanism of Amphotericin B. J Chem Theory Comput 2017; 13:3388-3397. [DOI: 10.1021/acs.jctc.7b00337] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- J. M. Falcón-González
- Laboratorio
de la Diversidad Biomolecular, Centro de Investigación y de Estudios Avanzados Unidad Monterrey, Vía del Conocimiento 201,
Parque PIIT, C.P. 66600, Apodaca, Nuevo León, México
- Unidad
Profesional Interdisciplinaria de Ingeniería Campus Guanajuato, Instituto Politécnico Nacional, Av. Mineral de Valenciana No. 200,
Col. Fraccionamiento Industrial Puerto Interior, C.P. 36275, Silao de la Victoria, Guanajuato, México
| | - G. Jiménez-Domínguez
- Laboratorio
de la Diversidad Biomolecular, Centro de Investigación y de Estudios Avanzados Unidad Monterrey, Vía del Conocimiento 201,
Parque PIIT, C.P. 66600, Apodaca, Nuevo León, México
| | - I. Ortega-Blake
- Instituto
de Ciencias Físicas, Universidad Nacional Autónoma de México, Apartado Postal 48-3, C.P. 62251, Cuernavaca, Morelos, México
| | - M. Carrillo-Tripp
- Laboratorio
de la Diversidad Biomolecular, Centro de Investigación y de Estudios Avanzados Unidad Monterrey, Vía del Conocimiento 201,
Parque PIIT, C.P. 66600, Apodaca, Nuevo León, México
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16
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Fábián B, Sega M, Voloshin VP, Medvedev NN, Jedlovszky P. Lateral Pressure Profile and Free Volume Properties in Phospholipid Membranes Containing Anesthetics. J Phys Chem B 2017; 121:2814-2824. [DOI: 10.1021/acs.jpcb.7b00990] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Balázs Fábián
- Department of Inorganic
and Analytical Chemistry, Budapest University of Technology and Economics, Szent Gellért tér 4, H-1111 Budapest, Hungary
- Institut UTINAM (CNRS UMR 6213), Université Bourgogne Franche-Comté, 16 route de Gray, F-25030 Besançon, France
| | - Marcello Sega
- Faculty of
Physics, University of Vienna, Sensengasse 8/9, A-1090 Vienna, Austria
| | - Vladimir P. Voloshin
- Institute of Chemical Kinetics and Combustion, Siberian Branch of the Russian Academy of Sciences (SB RAS), Novosibirsk 630090, Russia
| | - Nikolai N. Medvedev
- Novosibirsk State University, Novosibirsk 630090, Russia
- Institute of Chemical Kinetics and Combustion, Siberian Branch of the Russian Academy of Sciences (SB RAS), Novosibirsk 630090, Russia
| | - Pál Jedlovszky
- Department of Chemistry, Eszterházy Károly University, Leányka utca 6, H-3300 Eger, Hungary
- MTA-BME Research Group of Technical Analytical Chemistry, Szent Gellért tér
4, H-1111 Budapest, Hungary
- Laboratory of Interfaces and Nanosize Systems,
Institute of Chemistry, Eötvös Loránd University, Pázmány Peter Stny 1/A, H-1117 Budapest, Hungary
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17
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Shahid F, Farooqui Z, Rizwan S, Abidi S, Parwez I, Khan F. Oral administration of Nigella sativa oil ameliorates the effect of cisplatin on brush border membrane enzymes, carbohydrate metabolism and antioxidant system in rat intestine. ACTA ACUST UNITED AC 2017; 69:299-306. [PMID: 28215571 DOI: 10.1016/j.etp.2017.02.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Revised: 01/30/2017] [Accepted: 02/07/2017] [Indexed: 12/25/2022]
Abstract
Cisplatin (CP) is an effective chemotherapeutic agent that induces gastrointestinal toxicity. Nigella sativa oil (NSO) has been shown to be beneficial in a wide range of gastrointestinal disorders. The present study investigates the possible protective effect of NSO on CP-induced gastrointestinal toxicity. NSO administration (2ml/kg bwt, orally), prior to and following, a single dose CP treatment (6mg/kg bwt. ip), significantly attenuated the CP-induced decrease in brush border membrane (BBM) enzyme activities in intestinal homogenates and BBM vesicles (BBMV). NSO administration also mitigated CP induced alterations in the activities of carbohydrate metabolism enzymes and in the enzymatic and non-enzymatic antioxidant parameters in the intestine. The results suggest that NSO by empowering the endogenous antioxidant system improves intestinal redox and metabolic status and restores BBM integrity in CP treated rats. Histopathological studies supported the biochemical findings. Thus, NSO may help prevent the accompanying gastrointestinal dysfunction in CP chemotherapy.
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Affiliation(s)
- Faaiza Shahid
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh 202002, U.P., India
| | - Zeba Farooqui
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh 202002, U.P., India
| | - Sana Rizwan
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh 202002, U.P., India
| | - Subuhi Abidi
- Department of Zoology, Faculty of Life Sciences, Aligarh Muslim University, Aligarh 202002, U.P., India
| | - Iqbal Parwez
- Department of Zoology, Faculty of Life Sciences, Aligarh Muslim University, Aligarh 202002, U.P., India
| | - Farah Khan
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh 202002, U.P., India.
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18
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Ermilova I, Lyubartsev AP. Extension of the Slipids Force Field to Polyunsaturated Lipids. J Phys Chem B 2016; 120:12826-12842. [DOI: 10.1021/acs.jpcb.6b05422] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Inna Ermilova
- Department of Materials and
Environmental Chemistry, Stockholm University, SE 106 91 Stockholm, Sweden
| | - Alexander P. Lyubartsev
- Department of Materials and
Environmental Chemistry, Stockholm University, SE 106 91 Stockholm, Sweden
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19
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Farooqui Z, Afsar M, Rizwan S, Khan AA, Khan F. Oral administration of Nigella sativa oil ameliorates the effect of cisplatin on membrane enzymes, carbohydrate metabolism and oxidative damage in rat liver. Toxicol Rep 2016; 3:328-335. [PMID: 28959553 PMCID: PMC5615832 DOI: 10.1016/j.toxrep.2016.02.004] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Revised: 02/09/2016] [Accepted: 02/09/2016] [Indexed: 11/12/2022] Open
Abstract
Cisplatin (CP) is a potent anti-cancer drug widely used against solid tumors. However, it exhibits pronounced adverse effects including hepatotoxicity. Several strategies were attempted to prevent CP hepatotoxicity but were not found suitable for therapeutic application. Nigella sativa has been shown to prevent/reduce the progression of certain type of cardiovascular, kidney and liver diseases. Present study investigates whether N. sativa oil (NSO) can prevent CP induced hepatotoxic effects. Rats were divided into four groups viz. control, CP, NSO and CPNSO. Animals in CPNSO and NSO group were administered NSO (2 ml/kg bwt, orally) with or without single hepatotoxic dose of CP (6 mg/kg bwt, i.p.) respectively. CP hepatotoxicity was recorded by increased serum ALT and AST activities. CP treatment caused oxidant/antioxidant imbalances as reflected by increased lipid peroxidation and decreased enzymatic and non-enzymatic antioxidants. Furthermore, the activities of various carbohydrate metabolism and membrane enzymes were altered by CP treatment. In contrast, NSO administration to CP treated rats, markedly ameliorated the CP elicited deleterious alterations in liver. Histopathological observations showed extensive liver damage in CP treated animals while greatly reduced tissue injury in CPNSO group. In conclusion, NSO appears to protect CP induced hepatotoxicity by improving energy metabolism and strengthening antioxidant defense mechanism.
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Key Words
- ACPase, acid phosphatase
- ALP, alkaline phosphatise
- ALT, alanine aminotransferase
- AST, aspartate aminotransferases
- Antioxidant
- BBM, brush border membrane
- BBMV, BBM vesicles
- BUN, blood urea nitrogen
- CAT, catalase
- CP, cisplatin
- Carbohydrate metabolism
- Chl, cholesterol
- Cisplatin
- FBPase, fructose 1,6
- G6PDH, glucose 6-phosphate dehydrogenase
- G6Pase, glucose 6-phosphatase
- GGTase, γ-glutamyl transferase
- GR, glutathione reductase
- GSH, glutathione
- GSHPx, glutathione peroxidise
- GST, glutathione S-transferase
- Glc, glucose
- H2O2, hydrogen peroxide
- HK, hexokinase
- LAP, leucine aminopeptidase
- LDH, lactate dehydrogenase
- LPO, lipid peroxidation
- MDA, malondialdehyde
- MDH, malate dehydrogenase
- ME, malic enzyme
- NADP, nicotinamide adenine dinucleotide phosphate
- NADPH, nicotinamide adenine dinucleotide phosphate reduced
- NSO, Nigella sativa oil
- Nigella sativa oil
- PLs, phospholipids
- PUFA, polyunsaturated fatty acids
- Pi, inorganic phosphate
- ROS, reactive oxygen species
- SH, sulfhydryl
- SOD, superoxide dismutase
- Scr, serum creatinine
- TCA, tricarboxylic acid
- TR, thioredoxin reductase
- μm, micrometer
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Affiliation(s)
- Zeba Farooqui
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh 202002, U.P., India
| | - Mohammad Afsar
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh 202002, U.P., India
| | - Sana Rizwan
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh 202002, U.P., India
| | - Aijaz Ahmed Khan
- Department of Anatomy, Faculty of Medicine, J. N. Medical College, Aligarh Muslim University, Aligarh 202002, U.P., India
| | - Farah Khan
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh 202002, U.P., India
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20
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The Deleterious Effects of Oxidative and Nitrosative Stress on Palmitoylation, Membrane Lipid Rafts and Lipid-Based Cellular Signalling: New Drug Targets in Neuroimmune Disorders. Mol Neurobiol 2015; 53:4638-58. [PMID: 26310971 DOI: 10.1007/s12035-015-9392-y] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2015] [Accepted: 08/11/2015] [Indexed: 12/18/2022]
Abstract
Oxidative and nitrosative stress (O&NS) is causatively implicated in the pathogenesis of Alzheimer's and Parkinson's disease, multiple sclerosis, chronic fatigue syndrome, schizophrenia and depression. Many of the consequences stemming from O&NS, including damage to proteins, lipids and DNA, are well known, whereas the effects of O&NS on lipoprotein-based cellular signalling involving palmitoylation and plasma membrane lipid rafts are less well documented. The aim of this narrative review is to discuss the mechanisms involved in lipid-based signalling, including palmitoylation, membrane/lipid raft (MLR) and n-3 polyunsaturated fatty acid (PUFA) functions, the effects of O&NS processes on these processes and their role in the abovementioned diseases. S-palmitoylation is a post-translational modification, which regulates protein trafficking and association with the plasma membrane, protein subcellular location and functions. Palmitoylation and MRLs play a key role in neuronal functions, including glutamatergic neurotransmission, and immune-inflammatory responses. Palmitoylation, MLRs and n-3 PUFAs are vulnerable to the corruptive effects of O&NS. Chronic O&NS inhibits palmitoylation and causes profound changes in lipid membrane composition, e.g. n-3 PUFA depletion, increased membrane permeability and reduced fluidity, which together lead to disorders in intracellular signal transduction, receptor dysfunction and increased neurotoxicity. Disruption of lipid-based signalling is a source of the neuroimmune disorders involved in the pathophysiology of the abovementioned diseases. n-3 PUFA supplementation is a rational therapeutic approach targeting disruptions in lipid-based signalling.
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21
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Arnold W, Giroud S, Valencak TG, Ruf T. Ecophysiology of Omega Fatty Acids: A Lid for Every Jar. Physiology (Bethesda) 2015; 30:232-40. [DOI: 10.1152/physiol.00047.2014] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Omega fatty acids affect various physiological functions, such as locomotion, cardiac function, and thermogenesis. We highlight evidence from animal models that points to pathways by which specific omega fatty acids exert differential effects. We suggest that optimizing the omega fatty acid composition of tissues involves trade-offs between costs and benefits of specific fatty acids.
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Affiliation(s)
- Walter Arnold
- Department of Integrative Biology and Evolution, Research Institute of Wildlife Ecology, University of Veterinary Medicine Vienna, Austria
| | - Sylvain Giroud
- Department of Integrative Biology and Evolution, Research Institute of Wildlife Ecology, University of Veterinary Medicine Vienna, Austria
| | - Teresa G. Valencak
- Department of Integrative Biology and Evolution, Research Institute of Wildlife Ecology, University of Veterinary Medicine Vienna, Austria
| | - Thomas Ruf
- Department of Integrative Biology and Evolution, Research Institute of Wildlife Ecology, University of Veterinary Medicine Vienna, Austria
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22
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Zhan H, Lazaridis T. Inclusion of lateral pressure/curvature stress effects in implicit membrane models. Biophys J 2013; 104:643-54. [PMID: 23442915 DOI: 10.1016/j.bpj.2012.12.022] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Revised: 12/06/2012] [Accepted: 12/10/2012] [Indexed: 02/06/2023] Open
Abstract
Implicit membrane models usually treat the membrane as a hydrophobic slab and neglect lateral pressure/curvature stress effects. As a result, they cannot distinguish, for example, PE from PC lipids. Here, the implicit membrane model IMM1 is extended to include these effects using a combination of classical thermodynamics and membrane elasticity theory. The proposed model is tested by molecular dynamics simulation of the peptides alamethicin, melittin, cyclotide kalata B1, 18A, and KKpL15. The lateral pressure term stabilizes interfacial binding due to the negative pressure at the hydrocarbon-water interface. In agreement with experiment, increase in the peptide/lipid molar ratio shifts the equilibrium from the interfacial to the transmembrane orientation. Simulations of mixed DOPC/DOPE bilayers show that increase of the DOPE mole fraction in general stabilizes interfacial orientations and destabilizes transmembrane orientations. The extent of the stabilization or destabilization varies depending on the exact position of the peptides. The computational results are in good agreement with experiments.
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Affiliation(s)
- Huan Zhan
- Department of Chemistry, City College of New York/City University of New York, New York, New York, USA
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23
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Rabinovich AL, Lyubartsev AP. Computer simulation of lipid membranes: Methodology and achievements. POLYMER SCIENCE SERIES C 2013. [DOI: 10.1134/s1811238213070060] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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24
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Rizwan S, Naqshbandi A, Khan F. Dietary flaxseed oil supplementation mitigates the effect of lead on the enzymes of carbohydrate metabolism, brush border membrane, and oxidative stress in rat kidney tissues. Biol Trace Elem Res 2013; 153:279-90. [PMID: 23613149 DOI: 10.1007/s12011-013-9669-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2012] [Accepted: 04/10/2013] [Indexed: 10/26/2022]
Abstract
Lead is a heavy metal widely distributed in the environment. Lead is a ubiquitous environmental toxin that is capable of causing numerous acute and chronic illnesses. Human and animal exposure demonstrates that lead is nephrotoxic. However, attempts to reduce lead-induced nephrotoxicity were not found suitable for clinical use. Recently, flaxseed oil (FXO), a rich source of ω-3 fatty acids and lignans, has been shown to prevent/reduce the progression of certain types of cardiovascular and renal disorders. In view of this, the present study investigates the protective effect of FXO on lead acetate (PbAc)-induced renal damage. Rats were pre-fed normal diet and the diet rich in FXO for 14 days, and then, four doses of lead acetate (25 mg/kg body weight) were administered intraperitoneally while still on diet. Various serum parameters, enzymes of carbohydrate metabolism, brush border membrane (BBM), and oxidative stress were analyzed in rat kidney. PbAc nephrotoxicity was characterized by increased serum creatinine and blood urea nitrogen. PbAc increased the activities of lactate dehydrogenase and NADP-malic enzyme, whereas it decreased malate and glucose-6-phosphate dehydrogenase, glucose-6-phosphatase, fructose-1, 6-bisphosphatase, and BBM enzyme activities. PbAc caused oxidant/antioxidant imbalances as reflected by increased lipid peroxidation and decreased activities of superoxide dismutase, glutathione peroxidase, and catalase. In contrast, FXO alone enhanced the enzyme activities of carbohydrate metabolism, BBM, and antioxidant defense system. FXO feeding to PbAc-treated rats markedly enhanced resistance to PbAc-elicited deleterious effects. In conclusion, dietary FXO supplementation ameliorated PbAc-induced specific metabolic alterations and oxidative damage by empowering antioxidant defense mechanism and improving BBM integrity and energy metabolism.
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Affiliation(s)
- Sana Rizwan
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, India
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25
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Orsi M, Essex JW. Physical properties of mixed bilayers containing lamellar and nonlamellar lipids: insights from coarse-grain molecular dynamics simulations. Faraday Discuss 2013; 161:249-72; discussion 273-303. [DOI: 10.1039/c2fd20110k] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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26
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Maftouni N, Amininasab M, Vali M, Ejtehadi M, Kowsari F. A Molecular Dynamics Simulation Study of Nanomechanical Properties of Asymmetric Lipid Bilayer. J Membr Biol 2012; 246:67-73. [DOI: 10.1007/s00232-012-9505-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2012] [Accepted: 09/19/2012] [Indexed: 11/30/2022]
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27
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Skjevik ÅA, Madej BD, Walker RC, Teigen K. LIPID11: a modular framework for lipid simulations using amber. J Phys Chem B 2012; 116:11124-36. [PMID: 22916730 DOI: 10.1021/jp3059992] [Citation(s) in RCA: 156] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Accurate simulation of complex lipid bilayers has long been a goal in condensed phase molecular dynamics (MD). Structure and function of membrane-bound proteins are highly dependent on the lipid bilayer environment and are challenging to study through experimental methods. Within Amber, there has been limited focus on lipid simulations, although some success has been seen with the use of the General Amber Force Field (GAFF). However, to date there are no dedicated Amber lipid force fields. In this paper we describe a new charge derivation strategy for lipids consistent with the Amber RESP approach and a new atom and residue naming and type convention. In the first instance, we have combined this approach with GAFF parameters. The result is LIPID11, a flexible, modular framework for the simulation of lipids that is fully compatible with the existing Amber force fields. The charge derivation procedure, capping strategy, and nomenclature for LIPID11, along with preliminary simulation results and a discussion of the planned long-term parameter development are presented here. Our findings suggest that LIPID11 is a modular framework feasible for phospholipids and a flexible starting point for the development of a comprehensive, Amber-compatible lipid force field.
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Affiliation(s)
- Åge A Skjevik
- Department of Biomedicine, University of Bergen, N-5009 Bergen, Norway
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28
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Klauda JB, Monje V, Kim T, Im W. Improving the CHARMM force field for polyunsaturated fatty acid chains. J Phys Chem B 2012; 116:9424-31. [PMID: 22697583 DOI: 10.1021/jp304056p] [Citation(s) in RCA: 121] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
CHARMM36 (C36) is the most up-to-date pairwise additive all-atom lipid force field and is able to accurately represent bilayer properties of saturated and monounsaturated lipid molecules in the natural constant particle, pressure, and temperature (NPT) ensemble. However, molecular dynamics (MD) simulations on 1-stearoyl-2-docosahexaenoyl-sn-glycerco-3-phosphocholine (SDPC) bilayers of the polyunsaturated fatty acid (PUFA) chains result in inaccuracies of the surface area per lipid (SA), deuterium order parameters (S(CD)), and X-ray form factors. Therefore, in this study, high-level quantum mechanical calculations are used to improve the dihedral potential of neighboring double bonds, and the corresponding force field is referred to as C36p. The SA for SDPC at 303 K increases from 63.2 ± 0.2 (C36) to 70.8 ± 0.2 (C36p) Å(2) and agrees favorably with X-ray diffraction results at 297 K. The resulting S(CD) are in excellent agreement with experimental values of both the sn-1 and sn-2 chains. Calculated NMR (13)C relaxation times and X-ray form factors from MD simulations of SDPC bilayers also agree with experiments. MD simulations of 1,2-diarachidonyl-phosphatidylcholine (DAPC) bilayers are used to further validate our force field parameters on a lipid with both chains containing PUFAs. As expected, the thickness of DAPC bilayers is reduced, and the SA is increased compared to the SDPC bilayers. This update in the PUFA force field should allow for accurate MD simulations of PUFA-containing bilayers in the NPT ensemble.
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Affiliation(s)
- Jeffery B Klauda
- Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, Maryland 20742, USA.
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Sato S, Kawamoto J, Sato SB, Watanabe B, Hiratake J, Esaki N, Kurihara T. Occurrence of a bacterial membrane microdomain at the cell division site enriched in phospholipids with polyunsaturated hydrocarbon chains. J Biol Chem 2012; 287:24113-21. [PMID: 22648406 DOI: 10.1074/jbc.m111.318311] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In this study, we found that phospholipids containing an eicosapentaenyl group form a novel membrane microdomain at the cell division site of a Gram-negative bacterium, Shewanella livingstonensis Ac10, using chemically synthesized fluorescent probes. The occurrence of membrane microdomains in eukaryotes and prokaryotes has been demonstrated with various imaging tools for phospholipids with different polar headgroups. However, few studies have focused on the hydrocarbon chain-dependent localization of membrane-resident phospholipids in vivo. We previously found that lack of eicosapentaenoic acid (EPA), a polyunsaturated fatty acid found at the sn-2 position of glycerophospholipids, causes a defect in cell division after DNA replication of S. livingstonensis Ac10. Here, we synthesized phospholipid probes labeled with a fluorescent 7-nitro-2,1,3-benzoxadiazol-4-yl (NBD) group to study the localization of EPA-containing phospholipids by fluorescence microscopy. A fluorescent probe in which EPA was bound to the glycerol backbone via an ester bond was found to be unsuitable for imaging because EPA was released from the probe by in vivo hydrolysis. To overcome this problem, we synthesized hydrolysis-resistant ether-type phospholipid probes. Using these probes, we found that the fluorescence localized between two nucleoids at the cell center during cell division when the cells were grown in the presence of the eicosapentaenyl group-containing probe (N-NBD-1-oleoyl-2-eicosapentaenyl-sn-glycero-3-phosphoethanolamine), whereas this localization was not observed with the oleyl group-containing control probe (N-NBD-1-oleoyl-2-oleyl-sn-glycero-3-phosphoethanolamine). Thus, phospholipids containing an eicosapentaenyl group are specifically enriched at the cell division site. Formation of a membrane microdomain enriched in EPA-containing phospholipids at the nucleoid occlusion site probably facilitates cell division.
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Affiliation(s)
- Sho Sato
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
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Khan MW, Priyamvada S, Khan SA, Khan S, Naqshbandi A, Yusufi ANK. Protective effect of ω-3 polyunsaturated fatty acids (PUFAs) on sodium nitroprusside-induced nephrotoxicity and oxidative damage in rat kidney. Hum Exp Toxicol 2012; 31:1035-49. [PMID: 22549094 DOI: 10.1177/0960327112444475] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Sodium nitroprusside (SNP) a nitric oxide (NO) donor has proven toxic effects. Dietary ω-3 polyunsaturated fatty acid (PUFA) has been shown to reduce the severity of numerous ailments. Present study examined whether intake of fish oil (FO)/flaxseed oil (FXO, Omega Nutrition, St Vancouver, Canada) would have protective effect against SNP-induced toxicity. Male Wistar rats (150 ± 10 g) were used in this study. Initially animals were divided into two groups: one fed on normal diet and the other on 15% FO/FXO for 15 days. On the 16th day, SNP (1.5 mg/kg body weight) was administered intraperitoneally for 7 days daily. After 7 days animals were killed, kidneys were harvested for further analysis. SNP induced nephrotoxicity by increasing serum creatinine and blood urea nitrogen, SNP significantly decreased malate dehydrogenase, glucose-6-phosphatase, fructose-1,6-bisphosphatase and malic enzyme but increased lactate dehydrogenase and glucose-6-phosphate dehydrogenase. Brush border membrane enzymes such as alkaline phosphatase, γ-glutamyl transpeptidase and leucine amino peptidase were also decreased. The activity of catalase and glutathione peroxidase decreased concomitantly with increased lipid peroxidation, indicating that the significant kidney damage has been inflicted by SNP. Feeding of FO and FXO with SNP ameliorated the changes in various parameters caused by SNP. The results of the present study suggest that ω-3 PUFA-enriched FO and FXO from seafoods and plant sources, respectively, are similarly effective in reducing SNP-induced nephrotoxicity and oxidative damage. Thus, vegetarians who cannot consume FO can have similar health benefits from plant-derived ω-3 PUFA.
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Affiliation(s)
- M W Khan
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, UP, India.
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31
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Khan MW, Priyamvada S, Khan SA, Khan S, Naqshbandi A, Yusufi ANK. Protective effect of ω-3 polyunsaturated fatty acids onL-arginine-induced nephrotoxicity and oxidative damage in rat kidney. Hum Exp Toxicol 2012; 31:1022-34. [DOI: 10.1177/0960327112440110] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- MW Khan
- Department of Biochemistry, Aligarh Muslim University, Aligarh, Uttar Pradesh, India
| | - S Priyamvada
- Department of Biochemistry, Aligarh Muslim University, Aligarh, Uttar Pradesh, India
| | - SA Khan
- Department of Biochemistry, Aligarh Muslim University, Aligarh, Uttar Pradesh, India
| | - S Khan
- Department of Biochemistry, Aligarh Muslim University, Aligarh, Uttar Pradesh, India
| | - A Naqshbandi
- Department of Biochemistry, Aligarh Muslim University, Aligarh, Uttar Pradesh, India
| | - ANK Yusufi
- Department of Biochemistry, Aligarh Muslim University, Aligarh, Uttar Pradesh, India
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32
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Determining the Gaussian curvature modulus of lipid membranes in simulations. Biophys J 2012; 102:1403-10. [PMID: 22455923 DOI: 10.1016/j.bpj.2012.02.013] [Citation(s) in RCA: 145] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2011] [Revised: 01/25/2012] [Accepted: 02/08/2012] [Indexed: 11/20/2022] Open
Abstract
The Gaussian curvature modulus κ¯ of lipid bilayers likely contributes more than 100 kcal/mol to every cellular fission or fusion event. This huge impact on membrane remodeling energetics might be a factor that codetermines the complex lipid composition of biomembranes through tuning of κ¯. Yet, its value has been measured only for a handful of simple lipids, and no simulation has so far determined it better than a factor of two, rendering a systematic investigation of such enticing speculations impossible. Here we propose a highly accurate method to determine κ¯ in computer simulations. It relies on the interplay between curvature stress and edge tension of partially curved axisymmetric membrane disks and requires determining their closing probability. For a simplified lipid model we obtain κ¯ and its relation to the normal bending modulus κ for membranes differing both in stiffness and spontaneous lipid curvature. The elastic ratio κ¯/κ can be determined with a few percent statistical accuracy. Its value agrees with the scarce experimental data, and its change with spontaneous lipid curvature is compatible with theoretical expectations, thereby granting additional information on monolayer properties. We also show that an alternative determination of these elastic parameters based on moments of the lateral stress profile gives markedly different and unphysical values.
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Saito H, Shinoda W. Cholesterol Effect on Water Permeability through DPPC and PSM Lipid Bilayers: A Molecular Dynamics Study. J Phys Chem B 2011; 115:15241-50. [DOI: 10.1021/jp201611p] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Hiroaki Saito
- Faculty of Mathematics and Physics, Institute of Science and Engineering, Kanazawa University, Kanazawa 920-1192, Japan
- CREST, Japan Science and Technology Agency (JST), 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
| | - Wataru Shinoda
- Nanosystem Research Institute (NRI), National Institute of Advanced Industrial Science and Technology (AIST), Central 2, 1-1-1 Umezono, Tsukuba 305-8568, Japan
- CREST, Japan Science and Technology Agency (JST), 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
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34
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Nakamura T, Shinoda W, Ikeshoji T. Novel numerical method for calculating the pressure tensor in spherical coordinates for molecular systems. J Chem Phys 2011; 135:094106. [DOI: 10.1063/1.3626410] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Mouritsen OG. Lipids, curvature, and nano-medicine. EUR J LIPID SCI TECH 2011; 113:1174-1187. [PMID: 22164124 PMCID: PMC3229985 DOI: 10.1002/ejlt.201100050] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2011] [Revised: 06/30/2011] [Accepted: 06/30/2011] [Indexed: 12/29/2022]
Abstract
The physical properties of the lamellar lipid-bilayer component of biological membranes are controlled by a host of thermodynamic forces leading to overall tensionless bilayers with a conspicuous lateral pressure profile and build-in curvature-stress instabilities that may be released locally or globally in terms of morphological changes. In particular, the average molecular shape and the propensity of the different lipid and protein species for forming non-lamellar and curved structures are a source of structural transitions and control of biological function. The effects of different lipids, sterols, and proteins on membrane structure are discussed and it is shown how one can take advantage of the curvature-stress modulations brought about by specific molecular agents, such as fatty acids, lysolipids, and other amphiphilic solutes, to construct intelligent drug-delivery systems that function by enzymatic triggering via curvature.Practical applications: The simple concept of lipid molecular shape and how it impacts on the structure of lipid aggregates, in particular the curvature and curvature stress in lipid bilayers and liposomes, can be exploited to construct liposome-based drug-delivery systems, e.g., for use as nano-medicine in cancer therapy. Non-lamellar-forming lysolipids and fatty acids, some of which may be designed to be prodrugs, can be created by phospholipase action in diseased tissues thereby providing for targeted drug release and proliferation of molecular entities with conical shape that break down the permeability barrier of the target cells and may hence enhance efficacy.
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Affiliation(s)
- Ole G Mouritsen
- MEMPHYS - Center for Biomembrane Physics, Department of Physics and Chemistry, University of Southern Denmark Campusvej, Odense M, Denmark
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36
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Warschawski DE, Arnold AA, Beaugrand M, Gravel A, Chartrand É, Marcotte I. Choosing membrane mimetics for NMR structural studies of transmembrane proteins. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2011; 1808:1957-74. [DOI: 10.1016/j.bbamem.2011.03.016] [Citation(s) in RCA: 239] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2010] [Revised: 03/28/2011] [Accepted: 03/29/2011] [Indexed: 12/11/2022]
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O’Connor JW, Klauda JB. Lipid Membranes with a Majority of Cholesterol: Applications to the Ocular Lens and Aquaporin 0. J Phys Chem B 2011; 115:6455-64. [DOI: 10.1021/jp108650u] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Joseph W. O’Connor
- Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, Maryland 20742, United States
| | - Jeffery B. Klauda
- Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, Maryland 20742, United States
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38
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Arnold W, Ruf T, Frey-Roos F, Bruns U. Diet-independent remodeling of cellular membranes precedes seasonally changing body temperature in a hibernator. PLoS One 2011; 6:e18641. [PMID: 21533242 PMCID: PMC3076425 DOI: 10.1371/journal.pone.0018641] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2010] [Accepted: 03/14/2011] [Indexed: 11/23/2022] Open
Abstract
Polyunsaturated fatty acids (PUFA) have a multitude of health effects. Their incorporation into membrane phospholipids (PL) is generally believed to depend directly on dietary influx. PL influence transmembrane protein activity and thus can compensate temperature effects; e.g. PL n-6 PUFA are thought to stabilize heart function at low body temperature (Tb), whereas long chain (>C18) n-3 PUFA may boost oxidative capacity. We found substantial remodeling of membranes in free-living alpine marmots which was largely independent of direct dietary supply. Organ PL n-6 PUFA and n-6 to n-3 ratios were highest at onset and end of hibernation after rapid increases during a brief transitional period prior to hibernation. In contrast, longer chain PL n-3 PUFA content was low at end of summer but maximal at end of hibernation. After termination of hibernation in spring, these changes in PL composition were rapidly reversed. Our results demonstrate selective trafficking of PUFA within the body, probably governed by a circannual endogenous rhythm, as hibernating marmots were in winter burrows isolated for seven months from food and external cues signaling the approaching spring. High concentrations of PL n-6 PUFA throughout hibernation are in line with their hypothesized function of boosting SERCA 2a activity at low Tb. Furthermore, we found increasing rate of rewarming from torpor during winter indicating increasing oxidative capacity that could be explained by the accumulation of long-chain PL n-3 PUFA. It may serve to minimize the time necessary for rewarming despite the increasing temperature range to be covered, because rewarming is a period of highest metabolic rate and hence production of reactive oxygen species. Considering the importance of PUFA for health our results may have important biomedical implications, as seasonal changes of Tb and associated remodeling of membranes are not restricted to hibernators but presumably common among endothermic organisms.
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Affiliation(s)
- Walter Arnold
- Research Institute of Wildlife Ecology, University of Veterinary Medicine, Vienna, Austria.
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Intramolecular hydrogen bonding in articaine can be related to superior bone tissue penetration: a molecular dynamics study. Biophys Chem 2010; 154:18-25. [PMID: 21227568 DOI: 10.1016/j.bpc.2010.12.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2010] [Revised: 12/08/2010] [Accepted: 12/08/2010] [Indexed: 11/24/2022]
Abstract
Local anesthetics (LAs) are drugs that cause reversible loss of nociception during surgical procedures. Articaine is a commonly used LA in dentistry that has proven to be exceptionally effective in penetrating bone tissue and induce anesthesia on posterior teeth in maxilla and mandibula. In the present study, our aim was to gain a deeper understanding of the penetration of articaine through biological membranes by studying the interactions of articaine with a phospholipid membrane. Our approach involves Langmuir monolayer experiments combined with molecular dynamics simulations. Membrane permeability of LAs can be modulated by pH due to a titratable amine group with a pKa value close to physiological pH. A change in protonation state is thus known to act as a lipophilicity switch in LAs. Our study shows that articaine has an additional unique lipophilicity switch in its ability to form an intramolecular hydrogen bond. We suggest this intramolecular hydrogen bond as a novel and additional solvent-dependent mechanism for modulation of lipophilicity of articaine which may enhance its diffusion through membranes and connective tissue.
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40
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Santo KP, Kovalenko A, Stepanova M. Self-Consistent Field Modeling of Three-Dimensional Morphologies of Branched Lipid Surfactant at Air-Water Interface. MACROMOL THEOR SIMUL 2010. [DOI: 10.1002/mats.200900076] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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41
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Raza Shaikh S. Diet-induced docosahexaenoic acid non-raft domains and lymphocyte function. Prostaglandins Leukot Essent Fatty Acids 2010; 82:159-64. [PMID: 20207118 DOI: 10.1016/j.plefa.2010.02.026] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2009] [Indexed: 11/16/2022]
Abstract
Docosahexaenoic acid (DHA) is an n-3 polyunsaturated fatty acid (PUFA) that generally suppresses the function of T lymphocytes and antigen presenting cells (APCs). An emerging mechanism by which DHA modifies lymphocyte function is through changes in the organization of sphingolipid/cholesterol lipid raft membrane domains. Two contradictory models have been proposed to explain how DHA exerts its effects through changes in raft organization. The biophysical model, developed in model membranes, shows that DHA-containing phospholipids form unique non-raft membrane domains, that are organizationally distinct from lipid rafts, which serve to alter the conformation and/or lateral organization of lymphocyte proteins. In contrast, the cellular model on DHA and rafts shows that DHA suppresses lymphocyte function, in part, by directly incorporating into lipid rafts and altering protein activity. To reconcile opposing biophysical and cellular viewpoints, a major revision to existing models is presented herein. Based largely on quantitative microscopy data, it is proposed that DHA, consumed through the diet, modifies lymphocyte function, in part, through the formation of nanometer scale DHA-rich domains. These nano-scale domains disrupt the optimal raft-dependent clustering of proteins necessary for initial signaling. The data covered in this review highlights the importance of understanding how dietary n-3 PUFAs modify lymphocyte membranes, which is essential toward developing these fatty acids as therapeutic agents for treating inflammatory diseases.
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Affiliation(s)
- Saame Raza Shaikh
- Department of Biochemistry and Molecular Biology, Brody School of Medicine, East Carolina University, Greenville, NC 28590, USA.
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Ermakov YA, Kamaraju K, Sengupta K, Sukharev S. Gadolinium ions block mechanosensitive channels by altering the packing and lateral pressure of anionic lipids. Biophys J 2010; 98:1018-27. [PMID: 20303859 PMCID: PMC2849073 DOI: 10.1016/j.bpj.2009.11.044] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2009] [Revised: 11/20/2009] [Accepted: 11/25/2009] [Indexed: 11/28/2022] Open
Abstract
Effects of polyvalent ions on the lateral packing of phospholipids have been known for decades, but the physiological consequences have not been systematically studied. Gd(3+) is a relatively nonspecific agent that blocks mechano-gated channels with a variable affinity. In this study, we show that the large mechanosensitive channel MscL of Escherichia coli is effectively blocked by Gd(3+) only when reconstituted with negatively charged phospholipids (e.g., PS). Taking this lead, we studied effects of Gd(3+) on monolayers and unilamellar vesicles made of natural brain PS, DMPS, and its mixtures with DMPC. In monolayer experiments, we found that muM Gd(3+) present in the subphase leads to approximately 8% lateral compaction of brain PS (at 35 mN/m). Gd(3+) more strongly shrinks and rigidifies DMPS films causing a spontaneous liquid expanded-to-compact transition to the limiting 40 A(2)/mol. Pressure-area isotherms of uncharged DMPC were unaffected by Gd(3+), and neutralization of DMPS surface by low pH did not produce strong compaction. Upshifts of surface potential isotherms of DMPS monolayers reflected changes in the diffuse double layer due to neutralization of headgroup charges by Gd(3+), whereas the increased packing density produced up to a 200 mV change in the interfacial dipole potential. The slopes of surface potential versus reciprocal area predicted that Gd(3+) induced a modest ( approximately 18%) increase in the magnitude of the individual lipid dipoles in DMPS. Isothermal titration calorimetry indicated that binding of Gd(3+) to DMPS liposomes in the gel state is endothermic, whereas binding to liquid crystalline liposomes produces heat consistent with the isothermal liquid-to-gel phase transition induced by the ion. Both titration curves suggested a K(b) of approximately 10(6) M(-1). We conclude that anionic phospholipids serve as high-affinity receptors for Gd(3+) ions, and the ion-induced compaction generates a lateral pressure increase estimated as tens of mN/m. This pressure can "squeeze" the channel and shift the equilibrium toward the closed state.
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Key Words
- dmpc, dimirystoyl phosphatidylcholine
- dmps, dimirystoyl phosphatidylserine
- edl, electric double layer
- gcs, gouy-chapman-stern approximation
- gd3+, gadolinium
- itc, isothermal titration calorimetry
- le-lc transition, liquid expanded–liquid compact transition
- mscl, mechanosensitive channel of large conductance
- mscs, mechanosensitive channel of small conductance
- pc, phosphatidylcholine
- pe, phosphatidylethanolamine
- ps, phosphatidylserine
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Affiliation(s)
- Yury A. Ermakov
- The Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, Moscow, Russia
| | - Kishore Kamaraju
- Department of Biology, University of Maryland, College Park, Maryland
| | - Krishnendu Sengupta
- Indian Association for the Cultivation of Sciences, Kolkata, West Bengal, India
| | - Sergei Sukharev
- Department of Biology, University of Maryland, College Park, Maryland
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Cloning and functional expression of an MscL ortholog from Rhizobium etli: characterization of a mechanosensitive channel. J Membr Biol 2010; 234:13-27. [PMID: 20177670 DOI: 10.1007/s00232-010-9235-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2009] [Accepted: 01/26/2010] [Indexed: 10/19/2022]
Abstract
Rhizobium etli is equipped with several systems to handle both hyper- and hypo-osmotic stress. For adaptation to hypo-osmotic stress, R. etli possesses a single gene with clear homology to MscS, four MscS-like channels and one ortholog of MscL (ReMscL, identity approximately 44% compared to Escherichia coli MscL). We subcloned and expressed the ReMscL channel ortholog from R. etli in E. coli to examine its activity by patch clamp in giant spheroplasts and characterized it at the single-channel level. We obtained evidence that ReMscL prevents the lysis of E. coli null mutant log-phase cells upon a rapid, osmotic downshock and identified a slight pH dependence for ReMscL activation. Here, we describe the facilitation of ReMscL activation by arachidonic acid (AA) and a reversible inhibitory effect of Gd(3+). The results obtained in these experiments suggest a stabilizing effect of micromolar AA and traces of Gd(3+) ions in the partially expanded conformation of the protein. Finally, we discuss a possible correlation between the number of gene paralogs for MS channels and the habitats of several microorganisms. Taken together, our data show that ReMscL may play an important role in free-living rhizobacteria during hypo-osmotic shock in the rhizosphere.
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Baoukina S, Marrink SJ, Tieleman DP. Lateral pressure profiles in lipid monolayers. Faraday Discuss 2010; 144:393-409; discussion 445-81. [DOI: 10.1039/b905647e] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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45
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Priyamvada S, Khan SA, Khan MW, Khan S, Farooq N, Khan F, Yusufi ANK. Studies on the protective effect of dietary fish oil on uranyl-nitrate-induced nephrotoxicity and oxidative damage in rat kidney. Prostaglandins Leukot Essent Fatty Acids 2010; 82:35-44. [PMID: 19931439 DOI: 10.1016/j.plefa.2009.10.009] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2009] [Accepted: 10/13/2009] [Indexed: 10/20/2022]
Abstract
Human and animal exposure demonstrates that uranium is nephrotoxic. However, attempts to reduce it were not found suitable for clinical use. Dietary fish oil (FO) enriched in omega-3 fatty acids reduces the severity of cardiovascular and renal diseases. Present study investigates the protective effect of FO on uranyl nitrate (UN)-induced renal damage. Rats prefed with experimental diets for 15 days, given single nephrotoxic dose of UN (0.5mg/kg body weight) intraperitoneally. After 5d of UN treatment, serum/urine parameters, enzymes of carbohydrate metabolism, brush border membrane (BBM), oxidative stress and phosphate transport were analyzed in rat kidney. UN nephrotoxicity was characterized by increased serum creatinine and blood urea nitrogen. UN increased the activity of lactate dehydrogenase and NADP-malic enzyme whereas decreased malate, isocitrate and glucose-6-phophate dehydrogenases; glucose-6-phophatase, fructose-1, 6-bisphosphatase and BBM enzyme activities. UN caused oxidant/antioxidant imbalances as reflected by increased lipid peroxidation, activities of superoxide dismutase, glutathione peroxidase and decreased catalase activity. Feeding FO alone increased activities of enzymes of glucose metabolism, BBM, oxidative stress and Pi transport. UN-elicited alterations were prevented by FO feeding. However, corn oil had no such effects and was not similarly effective. In conclusion, FO appears to protect against UN-induced nephrotoxicity by improving energy metabolism and antioxidant defense mechanism.
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Affiliation(s)
- Shubha Priyamvada
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh 202002, UP, India
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Shaikh SR, Locascio DS, Soni SP, Wassall SR, Stillwell W. Oleic- and docosahexaenoic acid-containing phosphatidylethanolamines differentially phase separate from sphingomyelin. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2009; 1788:2421-6. [PMID: 19735642 DOI: 10.1016/j.bbamem.2009.08.019] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2009] [Revised: 08/22/2009] [Accepted: 08/31/2009] [Indexed: 10/20/2022]
Abstract
A central tenet of the lipid raft model is the existence of non-raft domains. In support of this view, we have established in model membranes that a phosphatidylethanolamine (PE)-containing docosahexaenoic acid (DHA) forms organizationally distinct non-raft domains in the presence of sphingomyelin (SM) and cholesterol (Chol). We have shown that formation of DHA-rich domains is driven by unfavorable molecular interactions between the rigid Chol molecule and the highly flexible DHA acyl chain. However, the molecular interactions between SM and the DHA-containing PE, which could also contribute to the formation of DHA-rich non-raft domains, have not been sufficiently investigated. To address this issue, we use differential scanning calorimetry (DSC) to study the phase behavior of mixtures of SM with either 1-palmitoyl-2-docosahexaenoyl-sn-glycero-3-phosphoethanolamine (16:0-22:6PE) or 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanolamine (16:0-18:1PE), an oleic acid (OA)-containing control, over a wide range of concentrations. Deconvolution of binary DSC scans shows that both 16:0-22:6PE and 16:0-18:1PE phase separate from SM. Analysis of transition temperatures and partial phase diagrams, constructed from the DSC scans for the first time, shows that 16:0-22:6PE displays greater non-ideal mixing with SM compared to 16:0-18:1PE. Our findings support a model in which DHA- and OA-containing PEs differentially phase separate from SM over a wide range of molar ratios to initiate the formation of non-raft domains, which is greatly enhanced by DHA, but not OA, in the presence of cholesterol.
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Affiliation(s)
- Saame Raza Shaikh
- Department of Biochemistry and Molecular Biology, Brody School of Medicine, East Carolina University, 600 Moye Boulevard, Greenville, NC 27834, USA.
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Shaikh SR, Rockett BD, Salameh M, Carraway K. Docosahexaenoic acid modifies the clustering and size of lipid rafts and the lateral organization and surface expression of MHC class I of EL4 cells. J Nutr 2009; 139:1632-9. [PMID: 19640970 DOI: 10.3945/jn.109.108720] [Citation(s) in RCA: 95] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
An emerging molecular mechanism by which docosahexaenoic acid (DHA) exerts its effects is modification of lipid raft organization. The biophysical model, based on studies with liposomes, shows that DHA avoids lipid rafts because of steric incompatibility between DHA and cholesterol. The model predicts that DHA does not directly modify rafts; rather, it incorporates into nonrafts to modify the lateral organization and/or conformation of membrane proteins, such as the major histocompatibility complex (MHC) class I. Here, we tested predictions of the model at a cellular level by incorporating oleic acid, eicosapentaenoic acid (EPA), and DHA, compared with a bovine serum albumin (BSA) control, into the membranes of EL4 cells. Quantitative microscopy showed that DHA, but not EPA, treatment, relative to the BSA control diminished lipid raft clustering and increased their size. Approximately 30% of DHA was incorporated directly into rafts without changing the distribution of cholesterol between rafts and nonrafts. Quantification of fluorescence colocalization images showed that DHA selectively altered MHC class I lateral organization by increasing the fraction of the nonraft protein into rafts compared with BSA. Both DHA and EPA treatments increased antibody binding to MHC class I compared with BSA. Antibody titration showed that DHA and EPA did not change MHC I conformation but increased total surface levels relative to BSA. Taken together, our findings are not in agreement with the biophysical model. Therefore, we propose a model that reconciles contradictory viewpoints from biophysical and cellular studies to explain how DHA modifies lipid rafts on several length scales. Our study supports the notion that rafts are an important target of DHA's mode of action.
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Affiliation(s)
- Saame Raza Shaikh
- Department of Biochemistry and Molecular Biology, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA.
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48
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Loukin SH, Su Z, Kung C. Hypotonic shocks activate rat TRPV4 in yeast in the absence of polyunsaturated fatty acids. FEBS Lett 2009; 583:754-8. [PMID: 19174160 DOI: 10.1016/j.febslet.2009.01.027] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2008] [Revised: 01/14/2009] [Accepted: 01/16/2009] [Indexed: 01/23/2023]
Abstract
Transient-receptor-potential channels (TRPs) underlie the sensing of chemicals, heat, and mechanical force. We expressed the rat TRPV1 and TRPV4 subtypes in yeast and monitored their activities in vivo as Ca(2+) rise using transgenic aequorin. Heat and capsaicin activate TRPV1 but not TRPV4 in yeast. Hypotonic shocks activate TRPV4 but not TRPV1. Osmotic swelling is modeled to activate enzyme(s), producing polyunsaturated fatty acids (PUFAs) to open TRPV4 in mammalian cells. This model relegates mechanosensitivity to the enzyme and not the channel. Yeast has only a single Delta9 fatty-acid monodesaturase and cannot make PUFAs suggesting an alternative mechanism for TRPV4 activation. We discuss possible explanations of this difference.
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Affiliation(s)
- Stephen H Loukin
- Laboratory of Molecular Biology, University of Wisconsin-Madison, 1525 Linden Drive Madison, WI 53706, USA
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Róg T, Vattulainen I, Jansen M, Ikonen E, Karttunen M. Comparison of cholesterol and its direct precursors along the biosynthetic pathway: effects of cholesterol, desmosterol and 7-dehydrocholesterol on saturated and unsaturated lipid bilayers. J Chem Phys 2009; 129:154508. [PMID: 19045210 DOI: 10.1063/1.2996296] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Despite extensive studies, the remarkable structure-function relationship of cholesterol in cellular membranes has remained rather elusive. This is exemplified by the fact that the membrane properties of cholesterol are distinctly different from those of many other sterols. Here we elucidate this issue through atomic-scale simulations of desmosterol and 7-dehydrocholesterol (7DHC), which are immediate precursors of cholesterol in its two distinct biosynthetic pathways. While desmosterol and 7DHC differ from cholesterol only by one additional double bond, we find that their influence on saturated lipid bilayers is substantially different from cholesterol. The capability to form ordered regions in a saturated (dipalmitoyl-phosphatidylcholine) membrane is given by cholesterol > 7DHC > desmosterol, indicating the important role of cholesterol in saturated lipid environments. For comparison, in an unsaturated (dioleoyl-phosphatidylcholine) bilayer, the membrane properties of all sterols were found to be essentially identical. Our studies indicate that the different membrane ordering properties of sterols can be characterized by a single experimentally accessible parameter, the sterol tilt. The smaller the tilt, the more ordered are the lipids around a given sterol. The molecular level mechanisms responsible for tilt modulation are found to be related to changes in local packing around the additional double bonds.
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Affiliation(s)
- Tomasz Róg
- Department of Physics, Helsinki University of Technology, Otakaari 1, F1-02150 Espoo, Finland
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The influence of 1-alkanols and external pressure on the lateral pressure profiles of lipid bilayers. Biophys J 2008; 95:5766-78. [PMID: 18849412 DOI: 10.1529/biophysj.108.142125] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The suggestion by Robert Cantor, that drug-induced pressure changes in lipid bilayers can change the conformational equilibrium between open and closed states of membrane proteins and thereby cause anesthesia, attracted much attention lately. Here, we studied the effect of both large external pressure and of 1-alkanols of different chain lengths--some of them anesthetics, others not--on the lateral pressure profiles across dimyristoylphosphatidylcholine (DMPC) bilayers by molecular dynamics simulations. For a pure DMPC bilayer, high pressure both reduced and broadened the tension at the interface hydrophobic/hydrophilic and diminished the repulsion between the phospholipid headgroups. Whereas the effect of ethanol on the lateral pressure profile was similar to the effect of a large external pressure on a DMPC bilayer, long-chain 1-alkanols significantly amplified local maxima and minima in the lateral pressure profile. For most 1-alkanols, external pressure had moderate effects and did not reverse the changes 1-alkanols exerted on the pressure profile. Nevertheless, assuming the bent helix model as a simple geometric model for the transmembrane region of a membrane protein, protein conformational equilibria were shifted in opposite directions by addition of 1-alkanols and additional application of external pressure.
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