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Jaramillo-Granada AM, Li J, Flores Villarreal A, Lozano O, Ruiz-Suárez JC, Monje-Galvan V, Sierra-Valdez FJ. Modulation of Phospholipase A 2 Membrane Activity by Anti-inflammatory Drugs. Langmuir 2024; 40:7038-7048. [PMID: 38511880 DOI: 10.1021/acs.langmuir.4c00084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/22/2024]
Abstract
The phospholipase A2 (PLA2) superfamily consists of lipolytic enzymes that hydrolyze specific cell membrane phospholipids and have long been considered a central hub of biosynthetic pathways, where their lipid metabolites exert a variety of physiological roles. A misregulated PLA2 activity is associated with mainly inflammatory-derived pathologies and thus has shown relevant therapeutic potential. Many natural and synthetic anti-inflammatory drugs (AIDs) have been proposed as direct modulators of PLA2 activity. However, despite the specific chemical properties that these drugs share in common, little is known about the indirect modulation able to finely tune membrane structural changes at the precise lipid-binding site. Here, we use a novel experimental strategy based on differential scanning calorimetry to systematically study the structural properties of lipid membrane systems during PLA2 cleavage and under the influence of several AIDs. For a better understanding of the AIDs-membrane interaction, we present a comprehensive and comparative set of molecular dynamics (MD) simulations. Our thermodynamic results clearly demonstrate that PLA2 cleavage is hindered by those AIDs that significantly reduce the lipid membrane cooperativity, while the rest of the AIDs oppositely tend to catalyze PLA2 activity to different extents. On the other hand, our MD simulations support experimental results by providing atomistic details on the binding, insertion, and dynamics of each AID on a pure lipid system; the drug efficacy to impact membrane cooperativity is related to the lipid order perturbation. This work suggests a membrane-based mechanism of action for diverse AIDs against PLA2 activity and provides relevant clues that must be considered in its modulation.
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Affiliation(s)
- Angela M Jaramillo-Granada
- Centro de Investigación y de Estudios Avanzados-Monterrey, Parque de Investigación e Innovación Tecnológica, Apodaca, Nuevo León 66600, Mexico
| | - Jinhui Li
- Department of Chemical and Biological Engineering, State University of New York (SUNY) at Buffalo, Buffalo, New York 14260, United States
| | | | - Omar Lozano
- Escuela de Medicina y Ciencias de la Salud, Tecnologico de Monterrey, Monterrey, Nuevo León 64460, Mexico
- Institute for Obesity Research, Tecnologico de Monterrey, Monterrey, Nuevo León 64849, Mexico
| | - J C Ruiz-Suárez
- Centro de Investigación y de Estudios Avanzados-Monterrey, Parque de Investigación e Innovación Tecnológica, Apodaca, Nuevo León 66600, Mexico
| | - Viviana Monje-Galvan
- Department of Chemical and Biological Engineering, State University of New York (SUNY) at Buffalo, Buffalo, New York 14260, United States
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2
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Romero LO, Caires R, Kaitlyn Victor A, Ramirez J, Sierra-Valdez FJ, Walsh P, Truong V, Lee J, Mayor U, Reiter LT, Vásquez V, Cordero-Morales JF. Linoleic acid improves PIEZO2 dysfunction in a mouse model of Angelman Syndrome. Nat Commun 2023; 14:1167. [PMID: 36859399 PMCID: PMC9977963 DOI: 10.1038/s41467-023-36818-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Accepted: 02/17/2023] [Indexed: 03/03/2023] Open
Abstract
Angelman syndrome (AS) is a neurogenetic disorder characterized by intellectual disability and atypical behaviors. AS results from loss of expression of the E3 ubiquitin-protein ligase UBE3A from the maternal allele in neurons. Individuals with AS display impaired coordination, poor balance, and gait ataxia. PIEZO2 is a mechanosensitive ion channel essential for coordination and balance. Here, we report that PIEZO2 activity is reduced in Ube3a deficient male and female mouse sensory neurons, a human Merkel cell carcinoma cell line and female human iPSC-derived sensory neurons with UBE3A knock-down, and de-identified stem cell-derived neurons from individuals with AS. We find that loss of UBE3A decreases actin filaments and reduces PIEZO2 expression and function. A linoleic acid (LA)-enriched diet increases PIEZO2 activity, mechano-excitability, and improves gait in male AS mice. Finally, LA supplementation increases PIEZO2 function in stem cell-derived neurons from individuals with AS. We propose a mechanism whereby loss of UBE3A expression reduces PIEZO2 function and identified a fatty acid that enhances channel activity and ameliorates AS-associated mechano-sensory deficits.
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Affiliation(s)
- Luis O Romero
- Department of Physiology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN, 38103, USA
- Integrated Biomedical Sciences Graduate Program, College of Graduate Health Sciences, Memphis, TN, 38163, USA
| | - Rebeca Caires
- Department of Physiology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN, 38103, USA
| | - A Kaitlyn Victor
- Department of Neurology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN, 38103, USA
| | - Juanma Ramirez
- Department of Biochemistry and Molecular Biology, Faculty of Science and Technology, UPV/EHU, Leioa, Bizkaia, Spain
| | - Francisco J Sierra-Valdez
- School of Engineering and Sciences, Tecnológico de Monterrey, Ave. Eugenio Garza Sada 2501 Sur, Monterrey, 64849, Mexico
| | | | | | - Jungsoo Lee
- Department of Physiology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN, 38103, USA
| | - Ugo Mayor
- Department of Biochemistry and Molecular Biology, Faculty of Science and Technology, UPV/EHU, Leioa, Bizkaia, Spain
- Ikerbasque, Basque Foundation for Science, Bilbao, Bizkaia, Spain
| | - Lawrence T Reiter
- Department of Neurology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN, 38103, USA
- Department of Anatomy and Neurobiology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN, 38104, USA
- Department of Pediatrics, College of Medicine, University of Tennessee Health Science Center, Memphis, TN, 38104, USA
| | - Valeria Vásquez
- Department of Physiology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN, 38103, USA.
| | - Julio F Cordero-Morales
- Department of Physiology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN, 38103, USA.
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Velez-Saboyá CS, Oropeza-Guzman E, Sierra-Valdez FJ, Ruiz-Suárez JC. Ca 2+-mediated enhancement of anesthetic diffusion across phospholipid multilamellar systems. Biochim Biophys Acta Biomembr 2020; 1863:183509. [PMID: 33189718 DOI: 10.1016/j.bbamem.2020.183509] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 10/14/2020] [Accepted: 11/09/2020] [Indexed: 11/28/2022]
Abstract
Although sharing common properties with other divalent cations, calcium ions induce fine-tuned electrostatic effects essential in many biological processes. Not only related with protein structure or ion channels, calcium is also determinant for other biomolecules such as lipids or even drugs. Cellular membranes are the first interaction barriers for drugs. Depending on their hydrophilic, hydrophobic or amphipathic properties, they have to overcome such barriers to permeate and diffuse through inner lipid bilayers, cells or even tissues. In this context, the role of calcium in the permeation of cationic amphiphilic drugs (CADs) through lipid membranes is not well understood. We combine differential scanning calorimetry (DSC) and Fourier-transform infrared spectroscopy (FTIR) to investigate the effect of Ca2+ on the interlamellar diffusion kinetics of the local anesthetic tetracaine (TTC) in multilamellar artificial membrane systems. Our DSC results show the interesting phenomenon that TTC diffusion can be modified in two different ways in the presence of Ca2+. Furthermore, TTC diffusion exhibits a thermal-dependent membrane interaction in the presence of Ca2+. The FTIR results suggest the presence of ion-dipole interactions between Ca2+ and the carbonyl group of TTC, leading us to hypothesize that Ca2+ destabilizes the hydration shell of TTC, which in turn diffuses deeper into the multilamellar lipid structures. Our results demonstrate the relevance of the Ca2+ ion in the drug permeation and diffusion through lipid bilayers.
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Affiliation(s)
- Carol S Velez-Saboyá
- Centro de Investigación y de Estudios Avanzados del IPN (CINVESTAV) Unidad Monterrey, Apodaca, Nuevo León 66600, Mexico
| | - Eric Oropeza-Guzman
- Centro de Investigación y de Estudios Avanzados del IPN (CINVESTAV) Unidad Monterrey, Apodaca, Nuevo León 66600, Mexico
| | - Francisco J Sierra-Valdez
- Tecnologico de Monterrey, Escuela de Ingeniería y Ciencias, Ave. Eugenio Garza Sada 2501, Monterrey, N.L. 64849, Mexico
| | - Jesús C Ruiz-Suárez
- Centro de Investigación y de Estudios Avanzados del IPN (CINVESTAV) Unidad Monterrey, Apodaca, Nuevo León 66600, Mexico.
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4
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Zapata-Morin PA, Sierra-Valdez FJ, Ruiz-Suárez JC. The cut-off effect of n-alcohols in lipid rafts: A lipid-dependent phenomenon ☆. J Mol Graph Model 2020; 101:107732. [PMID: 32920240 DOI: 10.1016/j.jmgm.2020.107732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 08/25/2020] [Accepted: 08/26/2020] [Indexed: 10/23/2022]
Abstract
n-Aliphatic alcohols act as anesthetics only up to a certain chain length, beyond which its biological activity disappears. This is known as the 'cut-off' phenomenon. Although the most accepted explanation is based on action sites in membrane proteins, it is not well understood why alcohols alter their functions. The structural dependence of these protein receptors to lipid domains known as 'lipid rafts', suggests a new approach to tackle the puzzling phenomenon. In this work, by performing molecular dynamic simulations (MDS) to explore the lipid role, we provide relevant molecular details about the membrane-alcohol interaction at the cut-off point regime. Since the high variability of the cut-off points found on protein receptors in neurons may be a consequence of differences in the lipid composition surrounding such proteins, our results could have a clear-cut importance.
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Affiliation(s)
- Patricio A Zapata-Morin
- Facultad de Ciencias Biológicas, Laboratorio de Micología y Fitopatología, Universidad Autónoma de Nuevo León, San Nicolás de Los Garza, Nuevo León, 66455, Mexico
| | - F J Sierra-Valdez
- Centro de Investigación Biomédica, Hospital Zambrano Hellion, TecSalud, Ave. Batallón de San Patricio 112, San Pedro Garza García, 66278, Nuevo León, Mexico; Tecnológico de Monterrey, Escuela de Ingeniería y Ciencias, Ave. Eugenio Garza Sada 2501 Sur, Monterrey, Nuevo León, 64849, Mexico
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5
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Romero LO, Massey AE, Mata-Daboin AD, Sierra-Valdez FJ, Chauhan SC, Cordero-Morales JF, Vásquez V. Dietary fatty acids fine-tune Piezo1 mechanical response. Nat Commun 2019; 10:1200. [PMID: 30867417 PMCID: PMC6416271 DOI: 10.1038/s41467-019-09055-7] [Citation(s) in RCA: 134] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Accepted: 02/18/2019] [Indexed: 12/18/2022] Open
Abstract
Mechanosensitive ion channels rely on membrane composition to transduce physical stimuli into electrical signals. The Piezo1 channel mediates mechanoelectrical transduction and regulates crucial physiological processes, including vascular architecture and remodeling, cell migration, and erythrocyte volume. The identity of the membrane components that modulate Piezo1 function remain largely unknown. Using lipid profiling analyses, we here identify dietary fatty acids that tune Piezo1 mechanical response. We find that margaric acid, a saturated fatty acid present in dairy products and fish, inhibits Piezo1 activation and polyunsaturated fatty acids (PUFAs), present in fish oils, modulate channel inactivation. Force measurements reveal that margaric acid increases membrane bending stiffness, whereas PUFAs decrease it. We use fatty acid supplementation to abrogate the phenotype of gain-of-function Piezo1 mutations causing human dehydrated hereditary stomatocytosis. Beyond Piezo1, our findings demonstrate that cell-intrinsic lipid profile and changes in the fatty acid metabolism can dictate the cell's response to mechanical cues.
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Affiliation(s)
- Luis O Romero
- Department of Physiology, College of Medicine, University of Tennessee Health Science Center, 71S. Manassas St., Memphis, TN, 38163, USA
| | - Andrew E Massey
- Department of Pharmaceutical Sciences and Institute of Biomarker and Molecular Therapeutics (IBMT), College of Pharmacy, University of Tennessee Health Science Center, 881 Madison Ave., Memphis, TN, 38163, USA
| | - Alejandro D Mata-Daboin
- Department of Physiology, College of Medicine, University of Tennessee Health Science Center, 71S. Manassas St., Memphis, TN, 38163, USA
| | - Francisco J Sierra-Valdez
- Department of Physiology, College of Medicine, University of Tennessee Health Science Center, 71S. Manassas St., Memphis, TN, 38163, USA
- Centro de Investigación Biomédica, Hospital Zambrano Hellion, TecSalud, Ave. Batallon de San Patricio 112, 66278, San Pedro Garza García, Nuevo León, Mexico
- Tecnólogico de Monterrey, Escuela de Ingeniería y Ciencias, Ave. Eugenio Garza Sada 2501 Sur, 64849, Monterrey, Nuevo León, Mexico
| | - Subhash C Chauhan
- Department of Pharmaceutical Sciences and Institute of Biomarker and Molecular Therapeutics (IBMT), College of Pharmacy, University of Tennessee Health Science Center, 881 Madison Ave., Memphis, TN, 38163, USA
| | - Julio F Cordero-Morales
- Department of Physiology, College of Medicine, University of Tennessee Health Science Center, 71S. Manassas St., Memphis, TN, 38163, USA
| | - Valeria Vásquez
- Department of Physiology, College of Medicine, University of Tennessee Health Science Center, 71S. Manassas St., Memphis, TN, 38163, USA.
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Sierra-Valdez FJ, Stein RA, Velissety P, Vasquez V, Cordero-Morales JF. Purification and Reconstitution of TRPV1 for Spectroscopic Analysis. J Vis Exp 2018. [PMID: 30035769 DOI: 10.3791/57796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Polymodal ion channels transduce multiple stimuli of different natures into allosteric changes; these dynamic conformations are challenging to determine and remain largely unknown. With recent advances in single-particle cryo-electron microscopy (cryo-EM) shedding light on the structural features of agonist binding sites and the activation mechanism of several ion channels, the stage is set for an in-depth dynamic analysis of their gating mechanisms using spectroscopic approaches. Spectroscopic techniques such as electron paramagnetic resonance (EPR) and double electron-electron resonance (DEER) have been mainly restricted to the study of prokaryotic ion channels that can be purified in large quantities. The requirement for large amounts of functional and stable membrane proteins has hampered the study of mammalian ion channels using these approaches. EPR and DEER offer many advantages, including determination of the structure and dynamic changes of mobile protein regions, albeit at low resolution, that might be difficult to obtain by X-ray crystallography or cryo-EM, and monitoring reversible gating transition (i.e., closed, open, sensitized, and desensitized). Here, we provide protocols for obtaining milligrams of functional detergent-solubilized transient receptor potential cation channel subfamily V member 1 (TRPV1) that can be labeled for EPR and DEER spectroscopy.
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Affiliation(s)
| | - Richard A Stein
- Department of Molecular Physiology and Biophysics, Vanderbilt University Medical Center
| | - Phanindra Velissety
- Department of Physiology, University of Tennessee Health Science Center; CuriRX, Inc
| | - Valeria Vasquez
- Department of Physiology, University of Tennessee Health Science Center
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7
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Caires R, Sierra-Valdez FJ, Millet JR, Herwig JD, Roan E, Vásquez V, Cordero-Morales JF. Omega-3 Fatty Acids Modulate TRPV4 Function through Plasma Membrane Remodeling. Cell Rep 2017; 21:246-258. [DOI: 10.1016/j.celrep.2017.09.029] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2017] [Revised: 07/18/2017] [Accepted: 09/07/2017] [Indexed: 12/26/2022] Open
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Pérez-Isidoro R, Sierra-Valdez FJ, Ruiz-Suárez JC. Anesthetic diffusion through lipid membranes depends on the protonation rate. Sci Rep 2014; 4:7534. [PMID: 25520016 PMCID: PMC4269894 DOI: 10.1038/srep07534] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Accepted: 11/26/2014] [Indexed: 12/16/2022] Open
Abstract
Hundreds of substances possess anesthetic action. However, despite decades of research and tests, a golden rule is required to reconcile the diverse hypothesis behind anesthesia. What makes an anesthetic to be local or general in the first place? The specific targets on proteins, the solubility in lipids, the diffusivity, potency, action time? Here we show that there could be a new player equally or even more important to disentangle the riddle: the protonation rate. Indeed, such rate modulates the diffusion speed of anesthetics into lipid membranes; low protonation rates enhance the diffusion for local anesthetics while high ones reduce it. We show also that there is a pH and membrane phase dependence on the local anesthetic diffusion across multiple lipid bilayers. Based on our findings we incorporate a new clue that may advance our understanding of the anesthetic phenomenon.
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Zapata-Morin PA, Sierra-Valdez FJ, Ruiz-Suárez JC. The interaction of local anesthetics with lipid membranes. J Mol Graph Model 2014; 53:200-205. [PMID: 25181454 DOI: 10.1016/j.jmgm.2014.08.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Revised: 08/11/2014] [Accepted: 08/12/2014] [Indexed: 11/28/2022]
Abstract
Molecular Dynamic Simulations are performed to evaluate the interaction of lidocaine, procaine and tetracaine with a lipid membrane. The main interest is to evaluate the structural changes produced by these local anesthetics in the bilayers. Penetration trajectories, interaction energies, entropy changes and an order parameter are calculated to quantify the destabilization of the lipid configurations. We show that such structural parameters give important information to understand how anesthetic agents influence the structure of plasma membranes. Graphic processing units (GPUs) are used in our simulations.
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10
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Sierra-Valdez FJ, Ruiz-Suárez J. Physical Aspects of the Cut-Off Effect of N-Alcohols in Pure Lipid Membranes. Biophys J 2014. [DOI: 10.1016/j.bpj.2013.11.3885] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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11
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Sierra-Valdez FJ, Forero-Quintero LS, Zapata-Morin PA, Costas M, Chavez-Reyes A, Ruiz-Suárez JC. The influence of non polar and polar molecules in mouse motile cells membranes and pure lipid bilayers. PLoS One 2013; 8:e59364. [PMID: 23565149 PMCID: PMC3614556 DOI: 10.1371/journal.pone.0059364] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2012] [Accepted: 02/13/2013] [Indexed: 11/18/2022] Open
Abstract
We report an experimental study of mouse sperm motility that shows chief aspects characteristic of neurons: the anesthetic (produced by tetracaine) and excitatory (produced by either caffeine or calcium) effects and their antagonic action. While tetracaine inhibits sperm motility and caffeine has an excitatory action, the combination of these two substances balance the effects, producing a motility quite similar to that of control cells. We also study the effects of these agents (anesthetic and excitatory) on the melting points of pure lipid liposomes constituted by 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and dipalmitoyl phosphatidic acid (DPPA). Tetracaine induces a large fluidization of the membrane, shifting the liposomes melting transition temperature to much lower values. The effect of caffeine is null, but its addition to tetracaine-doped liposomes greatly screen the fluidization effect. A high calcium concentration stiffens pure lipid membranes and strongly reduces the effect of tetracaine. Molecular Dynamics Simulations are performed to further understand our experimental findings at the molecular level. We find a strong correlation between the effect of antagonic molecules that could explain how the mechanical properties suitable for normal cell functioning are affected and recovered.
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Affiliation(s)
| | | | | | - Miguel Costas
- Departamento de Fisicoquímica, Facultad de Química, Universidad Nacional Autónoma de México, Cd. Universitaria, México D.F., México
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Sierra-Valdez FJ, Cisneros-Mejorado AJ, Sánchez Herrera DP, Ruiz-Suárez JC. A thermal study of cellular motility by optical time-resolved correlation. Rev Sci Instrum 2012; 83:044302. [PMID: 22559553 DOI: 10.1063/1.3700248] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The study of motor properties of cells under appropriate physical-chemical conditions is a significant problem nowadays. The standard techniques presently used do not allow to evaluate neither large samples nor to control their thermodynamic conditions. In this work, we report a cell motility sensor based on an optical technique with a time-resolved correlation, adapted in a system able to study several samples simultaneously. Image correlation analysis is used to follow their temporal behavior. A wide variety of motile cells, such as archaea, bacteria, spermatozoa, and even contractile cells, can be studied using this technique. Here, we tested our technique with the study of sperm motility. In particular, both the sperm motility and its prevalence are studied under a temperature range from 0 to 37 °C. We found that incubation at 10 °C presents the lengthiest prevalence in motility and observed, for the first time, an interesting thermal reversibility behavior.
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Affiliation(s)
- F J Sierra-Valdez
- Cinvestav-Monterrey, Vía del Conocimiento 201, PIIT, Autopista al Aeropuerto, Km. 9.5, Apodaca NL 66600, Mexico
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13
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Sierra-Valdez FJ, Pacheco-Vázquez F, Carvente O, Malloggi F, Cruz-Damas J, Rechtman R, Ruiz-Suárez JC. Acoustic gaps in a chain of magnetic spheres. Phys Rev E Stat Nonlin Soft Matter Phys 2010; 81:011301. [PMID: 20365362 DOI: 10.1103/physreve.81.011301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2009] [Revised: 11/11/2009] [Indexed: 05/29/2023]
Abstract
Acoustic gaps are normally observed in granular inhomogeneous structures made of composite materials. The modulation of the elastic properties in such media creates the coherent effects of scattering and interference that ultimately lead to frequency intervals where sound propagation is forbidden. Contrastingly, we report here an experimental observation of acoustic gaps in homogeneous media; specifically, in granular chains. The beads used in our study are magnetic. Therefore, instead of modulating the elastic properties of the chain, we modulate the magnetization (i.e., the contact forces). We also observe that the propagation speed of acoustic signals through the magnetic chains used in this study is at odds with the speed predicted by Hertz's law.
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