1
|
Foong YH, Caldwell B, Thorvaldsen JL, Krapp C, Mesaros CA, Zhou W, Kohli RM, Bartolomei MS. TET1 displays catalytic and non-catalytic functions in the adult mouse cortex. Epigenetics 2024; 19:2374979. [PMID: 38970823 PMCID: PMC11229741 DOI: 10.1080/15592294.2024.2374979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Accepted: 06/26/2024] [Indexed: 07/08/2024] Open
Abstract
TET1/2/3 dioxygenases iteratively demethylate 5-methylcytosine, beginning with the formation of 5-hydroxymethylcytosine (5hmC). The post-mitotic brain maintains higher levels of 5hmC than most peripheral tissues, and TET1 ablation studies have underscored the critical role of TET1 in brain physiology. However, deletion of Tet1 precludes the disentangling of the catalytic and non-catalytic functions of TET1. Here, we dissect these functions of TET1 by comparing adult cortex of Tet1 wildtype (Tet1 WT), a novel Tet1 catalytically dead mutant (Tet1 HxD), and Tet1 knockout (Tet1 KO) mice. Using DNA methylation array, we uncover that Tet1 HxD and KO mutations perturb the methylation status of distinct subsets of CpG sites. Gene ontology (GO) analysis on specific differential 5hmC regions indicates that TET1's catalytic activity is linked to neuronal-specific functions. RNA-Seq further shows that Tet1 mutations predominantly impact the genes that are associated with alternative splicing. Lastly, we performed High-performance Liquid Chromatography Mass-Spectrometry lipidomics on WT and mutant cortices and uncover accumulation of lysophospholipids lysophosphatidylethanolamine and lysophosphatidylcholine in Tet1 HxD cortex. In summary, we show that Tet1 HxD does not completely phenocopy Tet1 KO, providing evidence that TET1 modulates distinct cortical functions through its catalytic and non-catalytic roles.
Collapse
Affiliation(s)
- Yee Hoon Foong
- Department of Cell and Developmental Biology, Perelman School of Medicine, Smilow Center for Translational Research, Philadelphia, PA, USA
| | - Blake Caldwell
- Department of Cell and Developmental Biology, Perelman School of Medicine, Smilow Center for Translational Research, Philadelphia, PA, USA
- Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia, USA
| | - Joanne L. Thorvaldsen
- Department of Cell and Developmental Biology, Perelman School of Medicine, Smilow Center for Translational Research, Philadelphia, PA, USA
| | - Christopher Krapp
- Department of Cell and Developmental Biology, Perelman School of Medicine, Smilow Center for Translational Research, Philadelphia, PA, USA
| | - Clementina A. Mesaros
- Translational Biomarkers Core, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Center of Excellence in Environmental Toxicology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Wanding Zhou
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Children’s Hospital of Philadelphia (CHOP), University of Pennsylvania, Philadelphia, PA, USA
- Penn Epigenetics Institute, Smilow Center for Translational Rsearch, Philadelphia, PA, USA
| | - Rahul M. Kohli
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Penn Epigenetics Institute, Smilow Center for Translational Rsearch, Philadelphia, PA, USA
- Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Marisa S. Bartolomei
- Department of Cell and Developmental Biology, Perelman School of Medicine, Smilow Center for Translational Research, Philadelphia, PA, USA
- Penn Epigenetics Institute, Smilow Center for Translational Rsearch, Philadelphia, PA, USA
| |
Collapse
|
2
|
Yadav P, Beura SK, Panigrahi AR, Kulkarni PP, Yadav MK, Munshi A, Singh SK. Lysophosphatidylcholine induces oxidative stress and calcium-mediated cell death in human blood platelets. Cell Biol Int 2024; 48:1266-1284. [PMID: 38837523 DOI: 10.1002/cbin.12192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 05/06/2024] [Accepted: 05/11/2024] [Indexed: 06/07/2024]
Abstract
Platelets are essential component of circulation that plays a major role in hemostasis and thrombosis. During activation and its demise, platelets release platelet-derived microvesicles, with lysophosphatidylcholine (LPC) being a prominent component in their lipid composition. LPC, an oxidized low-density lipoprotein, is involved in cellular metabolism, but its higher level is implicated in pathologies like atherosclerosis, diabetes, and inflammatory disorders. Despite this, its impact on platelet function remains relatively unexplored. To address this, we studied LPC's effects on washed human platelets. A multimode plate reader was employed to measure reactive oxygen species and intracellular calcium using H2DCF-DA and Fluo-4-AM, respectively. Flow cytometry was utilized to measure phosphatidylserine expression, mitochondrial membrane potential (ΔΨm), and mitochondrial permeability transition pore (mPTP) formation using FITC-Annexin V, JC-1, and CoCl2/calcein-AM, respectively. Additionally, platelet morphology and its ultrastructure were observed via phase contrast and electron microscopy. Sonoclot and light transmission aggregometry were employed to examine fibrin formation and platelet aggregation, respectively. The findings demonstrate that LPC induced oxidative stress and increased intracellular calcium in platelets, resulting in increased phosphatidylserine expression and reduced ΔΨm. LPC triggered caspase-independent platelet death and mPTP opening via cytosolic and mitochondrial calcium, along with microvesiculation and reduced platelet counts. LPC increased the platelet's size, adopting a balloon-shaped morphology, causing membrane fragmentation and releasing its cellular contents, while inducing a pro-coagulant phenotype with increased fibrin formation and reduced integrin αIIbβ3 activation. Conclusively, this study reveals LPC-induced oxidative stress and calcium-mediated platelet death, necrotic in nature with pro-coagulant properties, potentially impacting inflammation and repair mechanisms during vascular injury.
Collapse
Affiliation(s)
- Pooja Yadav
- Department of Zoology, School of Basic Sciences, Central University of Punjab, Ghudda, Bathinda, India
| | - Samir K Beura
- Department of Zoology, School of Basic Sciences, Central University of Punjab, Ghudda, Bathinda, India
| | - Abhishek R Panigrahi
- Department of Zoology, School of Basic Sciences, Central University of Punjab, Ghudda, Bathinda, India
| | - Paresh P Kulkarni
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Mithlesh K Yadav
- Department of Zoology, School of Basic Sciences, Central University of Punjab, Ghudda, Bathinda, India
| | - Anjana Munshi
- Department of Human Genetics and Molecular Medicine, Central University of Punjab, Ghudda, Bathinda, India
| | - Sunil K Singh
- Department of Zoology, School of Basic Sciences, Central University of Punjab, Ghudda, Bathinda, India
- Department of Biochemistry, School of Basic Sciences, Central University of Punjab, Ghudda, Bathinda, India
| |
Collapse
|
3
|
O'Hara MT, Shimozono TM, Dye KJ, Harris D, Yang Z. Surface hydrophilicity promotes bacterial twitching motility. mSphere 2024:e0039024. [PMID: 39194233 DOI: 10.1128/msphere.00390-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2024] [Accepted: 06/24/2024] [Indexed: 08/29/2024] Open
Abstract
Twitching motility is a form of bacterial surface translocation powered by the type IV pilus (T4P). It is frequently analyzed by interstitial colony expansion between agar and the polystyrene surfaces of petri dishes. In such assays, the twitching motility of Acinetobacter nosocomialis was observed with MacConkey but not Luria-Bertani (LB) agar media. One difference between these two media is the presence of bile salts as a selective agent in MacConkey but not in LB. Here, we demonstrate that the addition of bile salts to LB allowed A. nosocomialis to display twitching. Similarly, bile salts enhanced the twitching of Acinetobacter baumannii and Pseudomonas aeruginosa in LB. These observations suggest that there is a common mechanism, whereby bile salts enhance bacterial twitching and promote interstitial colony expansion. Bile salts disrupt lipid membranes and apply envelope stress as detergents. Surprisingly, their stimulatory effect on twitching appears not to be related to a bacterial physiological response to stressors. Rather, it is due to their ability to alter the physicochemical properties of a twitching surface. We observed that while other detergents promoted twitching like bile salts, stresses applied by antibiotics, including the outer membrane-targeting polymyxin B, did not enhance twitching motility. More importantly, bacteria displayed increased twitching on hydrophilic surfaces such as those of glass and tissue culture-treated polystyrene plastics, and bile salts no longer stimulated twitching on these surfaces. Together, our results show that altering the hydrophilicity of a twitching surface significantly impacts T4P functionality. IMPORTANCE The bacterial type IV pilus (T4P) is a critical virulence factor for many medically important pathogens, some of which are prioritized by the World Health Organization for their high levels of antibiotic resistance. The T4P is known to propel bacterial twitching motility, the analysis of which provides a convenient assay for T4P functionality. Here, we show that bile salts and other detergents augment the twitching of multiple bacterial pathogens. We identified the underlying mechanism as the alteration of surface hydrophilicity by detergents. Consequently, hydrophilic surfaces like those of glass or plasma-treated polystyrene promote bacterial twitching, bypassing the requirement for detergents. The implication is that surface properties, such as those of tissues and medical implants, significantly impact the functionality of bacterial T4P as a virulence determinant. This offers valuable insights for developing countermeasures against the colonization and infection by bacterial pathogens of critical importance to human health on a global scale.
Collapse
Affiliation(s)
- Megan T O'Hara
- Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia, USA
| | - Tori M Shimozono
- Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia, USA
| | - Keane J Dye
- Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia, USA
| | - David Harris
- Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia, USA
| | - Zhaomin Yang
- Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia, USA
| |
Collapse
|
4
|
Denieva Z, Kuzmin PI, Galimzyanov TR, Datta SAK, Rein A, Batishchev OV. Human Immunodeficiency Virus Type 1 Gag Polyprotein Modulates Membrane Physical Properties like a Surfactant: Potential Implications for Virus Assembly. ACS Infect Dis 2024; 10:2870-2885. [PMID: 38917054 PMCID: PMC11320576 DOI: 10.1021/acsinfecdis.4c00251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2024] [Revised: 06/17/2024] [Accepted: 06/18/2024] [Indexed: 06/27/2024]
Abstract
Human immunodeficiency virus (HIV) assembly at an infected cell's plasma membrane requires membrane deformation to organize the near-spherical shape of an immature virus. While the cellular expression of HIV Gag is sufficient to initiate budding of virus-like particles, how Gag generates membrane curvature is not fully understood. Using highly curved lipid nanotubes, we have investigated the physicochemical basis of the membrane activity of recombinant nonmyristoylated Gag-Δp6. Gag protein, upon adsorption onto the membrane, resulted in the shape changes of both charged and uncharged nanotubes. This shape change was more pronounced in the presence of charged lipids, especially phosphatidylinositol bisphosphate (PI(4,5)P2). We found that Gag modified the interfacial tension of phospholipid bilayer membranes, as judged by comparison with the effects of amphipathic peptides and nonionic detergent. Bioinformatic analysis demonstrated that a region of the capsid and SP1 domains junction of Gag is structurally similar to the amphipathic peptide magainin-1. This region accounts for integral changes in the physical properties of the membrane upon Gag adsorption, as we showed with the synthetic CA-SP1 junction peptide. Phenomenologically, membrane-adsorbed Gag could diminish the energetic cost of increasing the membrane area in a way similar to foam formation. We propose that Gag acts as a surface-active substance at the HIV budding site that softens the membrane at the place of Gag adsorption, lowering the energy for membrane bending. Finally, our experimental data and theoretical considerations give a lipid-centric view and common mechanism by which proteins could bend membranes, despite not having intrinsic curvature in their molecular surfaces or assemblies.
Collapse
Affiliation(s)
- Zaret
G. Denieva
- A.N.
Frumkin Institute of Physical Chemistry and Electrochemistry, RAS, Leninsky pr., 31, bld. 4, 119071 Moscow, Russia
| | - Peter I. Kuzmin
- A.N.
Frumkin Institute of Physical Chemistry and Electrochemistry, RAS, Leninsky pr., 31, bld. 4, 119071 Moscow, Russia
| | - Timur R. Galimzyanov
- A.N.
Frumkin Institute of Physical Chemistry and Electrochemistry, RAS, Leninsky pr., 31, bld. 4, 119071 Moscow, Russia
| | - Siddhartha A. K. Datta
- Retroviral
Assembly Section, HIV Dynamics and Replication Program, Center for
Cancer Research, National Cancer Institute,
National Institutes of Health, Frederick, Maryland 21702-1201, United States
| | - Alan Rein
- Retroviral
Assembly Section, HIV Dynamics and Replication Program, Center for
Cancer Research, National Cancer Institute,
National Institutes of Health, Frederick, Maryland 21702-1201, United States
| | - Oleg V. Batishchev
- A.N.
Frumkin Institute of Physical Chemistry and Electrochemistry, RAS, Leninsky pr., 31, bld. 4, 119071 Moscow, Russia
| |
Collapse
|
5
|
Sandesha VD, Naveen P, Manikanta K, Mahalingam SS, Girish KS, Kemparaju K. Hump-Nosed Pit Viper ( Hypnale hypnale) Venom-Induced Irreversible Red Blood Cell Aggregation, Inhibition by Monovalent Anti-Venom and N-Acetylcysteine. Cells 2024; 13:994. [PMID: 38920625 PMCID: PMC11201549 DOI: 10.3390/cells13120994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2024] [Revised: 06/03/2024] [Accepted: 06/05/2024] [Indexed: 06/27/2024] Open
Abstract
Envenomation by the Hypnale hypnale in the Western Ghats of India (particularly in the Malabar region of Kerala) and the subcontinent island nation of Sri Lanka is known to inflict devastating mortality and morbidity. Currently, H. hypnale bites in India are devoid of anti-venom regimens. A detailed characterization of the venom is essential to stress the need for therapeutic anti-venom. Notably, the deleterious effects of this venom on human blood cells have largely remained less explored. Therefore, in continuation of our previous study, in the present study, we envisioned investigating the effect of venom on the morphological and physiological properties of red blood cells (RBCs). The venom readily induced deleterious morphological changes and, finally, the aggregation of washed RBCs. The aggregation process was independent of the ROS and the intracellular Ca2+ ion concentration. Confocal and scanning electron microscopy (SEM) images revealed the loss of biconcave morphology and massive cytoskeletal disarray. Crenation or serrated plasma membrane projections were evenly distributed on the surface of the RBCs. The venom did not cause the formation of methemoglobin in washed RBCs but was significantly induced in whole blood. Venom did not affect glucose uptake and Na+/K+ -ATPase activity but inhibited glucose 6 phosphate dehydrogenase activity and decreased the fluidity of the plasma membrane. Venom-induced RBC aggregates exhibited pro-coagulant activity but without affecting platelet aggregation. In pre-incubation or co-treatment studies, none of the bioactive compounds, such as melatonin, curcumin, fisetin, berberine, and quercetin, sugars such as mannose and galactose, and therapeutic polyvalent anti-venoms (Bharat and VINS) were inhibited, whereas only N-acetylcysteine and H. hypnale monovalent anti-venom could inhibit venom-induced deleterious morphological changes and aggregation of RBCs. In post-treatment studies, paradoxically, none of the bioactives and anti-venoms, including N-acetylcysteine and H. hypnale monovalent anti-venom, reversed the venom-induced RBC aggregates.
Collapse
Affiliation(s)
- Vaddaragudisalu D. Sandesha
- Department of Studies in Biochemistry, University of Mysore, Manasagangotri, Mysuru 570006, Karnataka, India; (V.D.S.); (P.N.); (K.M.)
| | - Puttaswamy Naveen
- Department of Studies in Biochemistry, University of Mysore, Manasagangotri, Mysuru 570006, Karnataka, India; (V.D.S.); (P.N.); (K.M.)
| | - Kurnegala Manikanta
- Department of Studies in Biochemistry, University of Mysore, Manasagangotri, Mysuru 570006, Karnataka, India; (V.D.S.); (P.N.); (K.M.)
| | - Shanmuga S. Mahalingam
- Department of Biological Sciences, School of Dental Medicine, Case Western Reserve University, Cleveland, OH 44106, USA;
| | - Kesturu S. Girish
- Department of Studies and Research in Biochemistry, Tumkur University, Tumakuru 572103, Karnataka, India
| | - Kempaiah Kemparaju
- Department of Studies in Biochemistry, University of Mysore, Manasagangotri, Mysuru 570006, Karnataka, India; (V.D.S.); (P.N.); (K.M.)
| |
Collapse
|
6
|
Dimitriou P, Li J, Jamieson WD, Schneider JJ, Castell OK, Barrow DA. Manipulation of encapsulated artificial phospholipid membranes using sub-micellar lysolipid concentrations. Commun Chem 2024; 7:120. [PMID: 38824266 PMCID: PMC11144220 DOI: 10.1038/s42004-024-01209-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Accepted: 05/24/2024] [Indexed: 06/03/2024] Open
Abstract
Droplet Interface Bilayers (DIBs) constitute a commonly used model of artificial membranes for synthetic biology research applications. However, their practical use is often limited by their requirement to be surrounded by oil. Here we demonstrate in-situ bilayer manipulation of submillimeter, hydrogel-encapsulated droplet interface bilayers (eDIBs). Monolithic, Cyclic Olefin Copolymer/Nylon 3D-printed microfluidic devices facilitated the eDIB formation through high-order emulsification. By exposing the eDIB capsules to varying lysophosphatidylcholine (LPC) concentrations, we investigated the interaction of lysolipids with three-dimensional DIB networks. Micellar LPC concentrations triggered the bursting of encapsulated droplet networks, while at lower concentrations the droplet network endured structural changes, precisely affecting the membrane dimensions. This chemically-mediated manipulation of enclosed, 3D-orchestrated membrane mimics, facilitates the exploration of readily accessible compartmentalized artificial cellular machinery. Collectively, the droplet-based construct can pose as a chemically responsive soft material for studying membrane mechanics, and drug delivery, by controlling the cargo release from artificial cell chassis.
Collapse
Affiliation(s)
- Pantelitsa Dimitriou
- School of Engineering, Cardiff University, Queen's Buildings, Cardiff, CF24 3AA, UK.
| | - Jin Li
- School of Engineering, Cardiff University, Queen's Buildings, Cardiff, CF24 3AA, UK.
| | - William David Jamieson
- School of Pharmacy and Pharmaceutical Sciences, College of Biomedical and Life Sciences, Cardiff University, Redwood Building, Kind Edward VII Avenue, Cardiff, CF10 3NB, UK
| | - Johannes Josef Schneider
- Institute of Applied Mathematics and Physics, School of Engineering, Zurich University of Applied Sciences, Technikumstr. 9, 8401, Winterthur, Switzerland
| | - Oliver Kieran Castell
- School of Pharmacy and Pharmaceutical Sciences, College of Biomedical and Life Sciences, Cardiff University, Redwood Building, Kind Edward VII Avenue, Cardiff, CF10 3NB, UK
| | - David Anthony Barrow
- School of Engineering, Cardiff University, Queen's Buildings, Cardiff, CF24 3AA, UK
| |
Collapse
|
7
|
Duché G, Sanderson JM. The Chemical Reactivity of Membrane Lipids. Chem Rev 2024; 124:3284-3330. [PMID: 38498932 PMCID: PMC10979411 DOI: 10.1021/acs.chemrev.3c00608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Revised: 02/27/2024] [Accepted: 02/28/2024] [Indexed: 03/20/2024]
Abstract
It is well-known that aqueous dispersions of phospholipids spontaneously assemble into bilayer structures. These structures have numerous applications across chemistry and materials science and form the fundamental structural unit of the biological membrane. The particular environment of the lipid bilayer, with a water-poor low dielectric core surrounded by a more polar and better hydrated interfacial region, gives the membrane particular biophysical and physicochemical properties and presents a unique environment for chemical reactions to occur. Many different types of molecule spanning a range of sizes, from dissolved gases through small organics to proteins, are able to interact with membranes and promote chemical changes to lipids that subsequently affect the physicochemical properties of the bilayer. This Review describes the chemical reactivity exhibited by lipids in their membrane form, with an emphasis on conditions where the lipids are well hydrated in the form of bilayers. Key topics include the following: lytic reactions of glyceryl esters, including hydrolysis, aminolysis, and transesterification; oxidation reactions of alkenes in unsaturated fatty acids and sterols, including autoxidation and oxidation by singlet oxygen; reactivity of headgroups, particularly with reactive carbonyl species; and E/Z isomerization of alkenes. The consequences of reactivity for biological activity and biophysical properties are also discussed.
Collapse
Affiliation(s)
- Genevieve Duché
- Génie
Enzimatique et Cellulaire, Université
Technologique de Compiègne, Compiègne 60200, France
| | - John M Sanderson
- Chemistry
Department, Durham University, Durham DH1 3LE, United Kingdom
| |
Collapse
|
8
|
Willdigg JR, Patel Y, Arquilevich BE, Subramanian C, Frank MW, Rock CO, Helmann JD. The Bacillus subtilis cell envelope stress-inducible ytpAB operon modulates membrane properties and contributes to bacitracin resistance. J Bacteriol 2024; 206:e0001524. [PMID: 38323910 PMCID: PMC10955860 DOI: 10.1128/jb.00015-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Accepted: 01/17/2024] [Indexed: 02/08/2024] Open
Abstract
Antibiotics that inhibit peptidoglycan synthesis trigger the activation of both specific and general protective responses. σM responds to diverse antibiotics that inhibit cell wall synthesis. Here, we demonstrate that cell wall-inhibiting drugs, such as bacitracin and cefuroxime, induce the σM-dependent ytpAB operon. YtpA is a predicted hydrolase previously proposed to generate the putative lysophospholipid antibiotic bacilysocin (lysophosphatidylglycerol), and YtpB is the branchpoint enzyme for the synthesis of membrane-localized C35 terpenoids. Using targeted lipidomics, we reveal that YtpA is not required for the production of lysophosphatidylglycerol. Nevertheless, ytpA was critical for growth in a mutant strain defective for homeoviscous adaptation due to a lack of genes for the synthesis of branched chain fatty acids and the Des phospholipid desaturase. Consistently, overexpression of ytpA increased membrane fluidity as monitored by fluorescence anisotropy. The ytpA gene contributes to bacitracin resistance in mutants additionally lacking the bceAB or bcrC genes, which directly mediate bacitracin resistance. These epistatic interactions support a model in which σM-dependent induction of the ytpAB operon helps cells tolerate bacitracin stress, either by facilitating the flipping of the undecaprenyl phosphate carrier lipid or by impacting the assembly or function of membrane-associated complexes involved in cell wall homeostasis.IMPORTANCEPeptidoglycan synthesis inhibitors include some of our most important antibiotics. In Bacillus subtilis, peptidoglycan synthesis inhibitors induce the σM regulon, which is critical for intrinsic antibiotic resistance. The σM-dependent ytpAB operon encodes a predicted hydrolase (YtpA) and the enzyme that initiates the synthesis of C35 terpenoids (YtpB). Our results suggest that YtpA is critical in cells defective in homeoviscous adaptation. Furthermore, we find that YtpA functions cooperatively with the BceAB and BcrC proteins in conferring intrinsic resistance to bacitracin, a peptide antibiotic that binds tightly to the undecaprenyl-pyrophosphate lipid carrier that sustains peptidoglycan synthesis.
Collapse
Affiliation(s)
| | - Yesha Patel
- Department of Microbiology, Cornell University, Ithaca, New York, USA
| | | | - Chitra Subramanian
- Department of Host Microbe Interactions, St. Jude Children’s Research Hospital, Memphis, Tennessee, USA
| | - Matthew W. Frank
- Department of Host Microbe Interactions, St. Jude Children’s Research Hospital, Memphis, Tennessee, USA
| | - Charles O. Rock
- Department of Host Microbe Interactions, St. Jude Children’s Research Hospital, Memphis, Tennessee, USA
| | - John D. Helmann
- Department of Microbiology, Cornell University, Ithaca, New York, USA
| |
Collapse
|
9
|
Karal MAS, Billah MM, Ahmed M, Ahamed MK. A review on the measurement of the bending rigidity of lipid membranes. SOFT MATTER 2023; 19:8285-8304. [PMID: 37873600 DOI: 10.1039/d3sm00882g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2023]
Abstract
This review provides an overview of the latest developments in both experimental and simulation techniques used to assess the bending rigidity of lipid membranes. It places special emphasis on experimental methods that utilize model vesicles to manipulate lipid compositions and other experimental parameters to determine the bending rigidity of the membrane. It also describes two commonly used simulation methods for estimating bending rigidity. The impact of various factors on membrane bending rigidity is summarized, including cholesterol, lipids, salt concentration, surface charge, membrane phase state, peptides, proteins, and polyethylene glycol. These factors are shown to influence the bending rigidity, contributing to a better understanding of the biophysical properties of membranes and their role in biological processes. Furthermore, the review discusses future directions and potential advancements in this research field, highlighting areas where further investigation is required.
Collapse
Affiliation(s)
- Mohammad Abu Sayem Karal
- Department of Physics, Bangladesh University of Engineering and Technology, Dhaka 1000, Bangladesh.
| | - Md Masum Billah
- Department of Physics, Jashore University of Science and Technology, Jashore 7408, Bangladesh
| | - Marzuk Ahmed
- Integrated Bioscience Section, Graduate School of Science and Technology, Shizuoka University, Shizuoka 422-8529, Japan
| | - Md Kabir Ahamed
- Radiation, Transport and Waste Safety Division, Bangladesh Atomic Energy Regulatory Authority, Agargaon, Dhaka 1207, Bangladesh
| |
Collapse
|
10
|
Hua L, Kaiser M, Carabadjac I, Meister A, Hause G, Heerklotz H. Vesicle budding caused by lysolipid-induced asymmetry stress. Biophys J 2023; 122:4011-4022. [PMID: 37649254 PMCID: PMC10598287 DOI: 10.1016/j.bpj.2023.08.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 08/10/2023] [Accepted: 08/28/2023] [Indexed: 09/01/2023] Open
Abstract
Lysolipids such as lauroyl, myristoyl, and palmitoyl lysophosphatidylcholine (LPC) insert into the outer leaflet of liposomes but do not flip to the inner leaflet over many hours. This way, they create asymmetry stress between the intrinsic areas of the two leaflets. We have studied how this stress is relaxed with particular emphasis on the budding and fission of small (diameter 20-30 nm) daughter vesicles (DVs). Asymmetric flow field-flow fractionation was utilized to quantify the extent of budding from large unilamellar vesicles after exposure to LPC. Budding starts at a low threshold of the order of 2 mol% LPC in the outer (and ≈0 mol% LPC in the inner) leaflet. We see reason to assume that the fractional fluorescence intensity from DVs is a good approximation for the fraction of membrane lipid, POPC, transferred into DVs. Accordingly, budding starts with a "budding power" of ≈6 POPC molecules budding off per LPC added, corresponding to a more than 10-fold accumulation of LPC in the outer leaflet of DVs to ≈24 mol%. As long as budding is possible, little strain is built up in the membranes, a claim supported by the lack of changes in limiting fluorescence anisotropy, rotational correlation time, and fluorescence lifetime of symmetrically and asymmetrically inserted TMA-DPH. At physiological osmolarity, budding is typically limited to 20-30% of budded fraction with some batch-to-batch variation, but independent of the LPC species. We hypothesize that the budding limit is determined by the excess area of the liposomes upon preparation, which is then used up upon budding given the larger area-to-volume ratio of smaller liposomes. As the mother vesicles approach ideal spheres, budding must stop. This is qualitatively supported by increased and decreased budding limits of osmotically predeflated and preinflated vesicles, respectively.
Collapse
Affiliation(s)
- Lisa Hua
- Institute of Pharmaceutical Sciences, University of Freiburg, Freiburg, Germany.
| | - Michael Kaiser
- Institute of Pharmaceutical Sciences, University of Freiburg, Freiburg, Germany
| | - Iulia Carabadjac
- Institute of Pharmaceutical Sciences, University of Freiburg, Freiburg, Germany
| | - Annette Meister
- ZIK HALOmem and Institute of Biochemistry and Biotechnology, MLU Halle-Wittenberg, Halle, Germany
| | - Gerd Hause
- Biozentrum, MLU Halle-Wittenberg, Halle, Germany
| | - Heiko Heerklotz
- Institute of Pharmaceutical Sciences, University of Freiburg, Freiburg, Germany; Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Canada; Signaling Research Center BIOSS, University of Freiburg, Freiburg, Germany.
| |
Collapse
|
11
|
Speer D, Salvador-Castell M, Huang Y, Liu GY, Sinha SK, Parikh AN. Surfactant-Mediated Structural Modulations to Planar, Amphiphilic Multilamellar Stacks. J Phys Chem B 2023; 127:7497-7508. [PMID: 37584633 PMCID: PMC10476200 DOI: 10.1021/acs.jpcb.3c01654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 08/01/2023] [Indexed: 08/17/2023]
Abstract
The hydrophobic effect, a ubiquitous process in biology, is a primary thermodynamic driver of amphiphilic self-assembly. It leads to the formation of unique morphologies including two highly important classes of lamellar and micellar mesophases. The interactions between these two types of structures and their involved components have garnered significant interest because of their importance in key biochemical technologies related to the isolation, purification, and reconstitution of membrane proteins. This work investigates the structural organization of mixtures of the lamellar-forming phospholipid 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) and two zwitterionic micelle-forming surfactants, being n-dodecyl-N,N-dimethyl-3-ammonio-1-propanesulfonate (Zwittergent 3-12 or DDAPS) and 1-oleoyl-2-hydroxy-sn-glycero-3-phosphocholine (O-Lyso-PC), when assembled by water vapor hydration with X-ray diffraction measurements, brightfield optical microscopy, wide-field fluorescence microscopy, and atomic force microscopy. The results reveal that multilamellar mesophases of these mixtures can be assembled across a wide range of POPC to surfactant (POPC:surfactant) concentration ratios, including ratios far surpassing the classical detergent-saturation limit of POPC bilayers without significant morphological disruptions to the lamellar motif. The mixed mesophases generally decreased in lamellar spacing (D) and headgroup-to-headgroup distance (Dhh) with a higher concentration of the doped surfactant, but trends in water layer thickness (Dw) between each bilayer in the stack are highly variable. Further structural characteristics including mesophase topography, bilayer thickness, and lamellar rupture force were revealed by atomic force microscopy (AFM), exhibiting homogeneous multilamellar stacks with no significant physical differences with changes in the surfactant concentration within the mesophases. Taken together, the outcomes present the assembly of unanticipated and highly unique mixed mesophases with varied structural trends from the involved surfactant and lipidic components. Modulations in their structural properties can be attributed to the surfactant's chemical specificity in relation to POPC, such as the headgroup hydration and the hydrophobic chain tail mismatch. Taken together, our results illustrate how specific chemical complexities of surfactant-lipid interactions can alter the morphologies of mixed mesophases and thereby alter the kinetic pathways by which surfactants dissolve lipid mesophases in bulk aqueous solutions.
Collapse
Affiliation(s)
- Daniel
J. Speer
- Chemistry
Graduate Group, University of California,
Davis, One Shields Avenue, Davis, California 95616, United States
| | - Marta Salvador-Castell
- Department
of Physics, University of California, San
Diego, 9500 Gilman Drive, La Jolla, California 92093, United States
| | - Yuqi Huang
- Department
of Chemistry, University of California,
Davis, One Shields Avenue, Davis, California 95616, United States
| | - Gang-Yu Liu
- Department
of Chemistry, University of California,
Davis, One Shields Avenue, Davis, California 95616, United States
| | - Sunil K. Sinha
- Department
of Physics, University of California, San
Diego, 9500 Gilman Drive, La Jolla, California 92093, United States
| | - Atul N. Parikh
- Chemistry
Graduate Group, University of California,
Davis, One Shields Avenue, Davis, California 95616, United States
- Department
of Biomedical Engineering, University of
California, Davis, One
Shields Avenue, Davis, California 95616, United States
| |
Collapse
|
12
|
Gooran N, Tan SW, Yoon BK, Jackman JA. Unraveling Membrane-Disruptive Properties of Sodium Lauroyl Lactylate and Its Hydrolytic Products: A QCM-D and EIS Study. Int J Mol Sci 2023; 24:ijms24119283. [PMID: 37298235 DOI: 10.3390/ijms24119283] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Revised: 05/15/2023] [Accepted: 05/24/2023] [Indexed: 06/12/2023] Open
Abstract
Membrane-disrupting lactylates are an important class of surfactant molecules that are esterified adducts of fatty acid and lactic acid and possess industrially attractive properties, such as high antimicrobial potency and hydrophilicity. Compared with antimicrobial lipids such as free fatty acids and monoglycerides, the membrane-disruptive properties of lactylates have been scarcely investigated from a biophysical perspective, and addressing this gap is important to build a molecular-level understanding of how lactylates work. Herein, using the quartz crystal microbalance-dissipation (QCM-D) and electrochemical impedance spectroscopy (EIS) techniques, we investigated the real-time, membrane-disruptive interactions between sodium lauroyl lactylate (SLL)-a promising lactylate with a 12-carbon-long, saturated hydrocarbon chain-and supported lipid bilayer (SLB) and tethered bilayer lipid membrane (tBLM) platforms. For comparison, hydrolytic products of SLL that may be generated in biological environments, i.e., lauric acid (LA) and lactic acid (LacA), were also tested individually and as a mixture, along with a structurally related surfactant (sodium dodecyl sulfate, SDS). While SLL, LA, and SDS all had equivalent chain properties and critical micelle concentration (CMC) values, our findings reveal that SLL exhibits distinct membrane-disruptive properties that lie in between the rapid, complete solubilizing activity of SDS and the more modest disruptive properties of LA. Interestingly, the hydrolytic products of SLL, i.e., the LA + LacA mixture, induced a greater degree of transient, reversible membrane morphological changes but ultimately less permanent membrane disruption than SLL. These molecular-level insights support that careful tuning of antimicrobial lipid headgroup properties can modulate the spectrum of membrane-disruptive interactions, offering a pathway to design surfactants with tailored biodegradation profiles and reinforcing that SLL has attractive biophysical merits as a membrane-disrupting antimicrobial drug candidate.
Collapse
Affiliation(s)
- Negin Gooran
- School of Chemical Engineering and Translational Nanobioscience Research Center, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Sue Woon Tan
- School of Chemical Engineering and Translational Nanobioscience Research Center, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Bo Kyeong Yoon
- School of Healthcare and Biomedical Engineering, Chonnam National University, Yeosu 59626, Republic of Korea
| | - Joshua A Jackman
- School of Chemical Engineering and Translational Nanobioscience Research Center, Sungkyunkwan University, Suwon 16419, Republic of Korea
| |
Collapse
|
13
|
Mohamad Ali D, Hogeveen K, Orhant RM, Le Gal de Kerangal T, Ergan F, Ulmann L, Pencreac'h G. Lysophosphatidylcholine-DHA Specifically Induces Cytotoxic Effects of the MDA-MB-231 Human Breast Cancer Cell Line In Vitro-Comparative Effects with Other Lipids Containing DHA. Nutrients 2023; 15:2137. [PMID: 37432249 DOI: 10.3390/nu15092137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 04/27/2023] [Accepted: 04/28/2023] [Indexed: 07/12/2023] Open
Abstract
Docosahexaenoic acid (DHA, C22:6 ω-3) is a dietary polyunsaturated fatty acid that has an important role in human health. Epidemiological studies linked a high intake of DHA to a reduced risk of certain cancers. Recently, attention focused on how the lipid carrier in which DHA is delivered, i.e., esterified on acylglycerols, phospholipids, or free, affects its biological effects. However, studies comparing the effects of these different forms for DHA supply to cancer cells in vitro are limited. In this study, the effect of free DHA and five lipids carrying one to three DHA chains (LPC-DHA, PC-DHA, MAG-DHA, DAG-DHA and TAG-DHA) on the viability of the MDA-MB-231 breast cancer cell line was compared. Our results revealed a strong structure-function relationship of DHA-carrying lipids on the viability of MDA-MB-231 cells. Glycerophosphocholine-based lipids are the most effective DHA carriers in reducing the viability of MDA-MB-231 cells, with LPC-DHA being more effective (IC50 = 23.7 µM) than PC-DHA (IC50 = 67 µM). The other tested lipids are less toxic (MAG-DHA, free DHA) or even not toxic (DAG-DHA, TAG-DHA) under our conditions. Investigating the mechanism of cell death induced by LPC-DHA revealed increased oxidative stress and membrane cell damage.
Collapse
Affiliation(s)
- Dalal Mohamad Ali
- BiOSSE: Biology of Organisms, Stress, Health, Environment, IUT de Laval, Département Génie Biologique, Le Mans Université, F-53020 Laval, France
- Toulouse Biotechnology Institute, Equipe CIMEs, Université de Toulouse, CNRS, INRAE, INSA, F-31077 Toulouse, France
| | - Kevin Hogeveen
- Unité de Toxicologie des Contaminants, ANSES, F-35306 Fougères, France
| | - Rose-Marie Orhant
- BiOSSE: Biology of Organisms, Stress, Health, Environment, IUT de Laval, Département Génie Biologique, Le Mans Université, F-53020 Laval, France
| | - Tiphaine Le Gal de Kerangal
- BiOSSE: Biology of Organisms, Stress, Health, Environment, IUT de Laval, Département Génie Biologique, Le Mans Université, F-53020 Laval, France
| | - Françoise Ergan
- BiOSSE: Biology of Organisms, Stress, Health, Environment, IUT de Laval, Département Génie Biologique, Le Mans Université, F-53020 Laval, France
| | - Lionel Ulmann
- BiOSSE: Biology of Organisms, Stress, Health, Environment, IUT de Laval, Département Génie Biologique, Le Mans Université, F-53020 Laval, France
| | - Gaëlle Pencreac'h
- BiOSSE: Biology of Organisms, Stress, Health, Environment, IUT de Laval, Département Génie Biologique, Le Mans Université, F-53020 Laval, France
| |
Collapse
|
14
|
Rice A, Zimmerberg J, Pastor RW. Initiation and evolution of pores formed by influenza fusion peptides probed by lysolipid inclusion. Biophys J 2023; 122:1018-1032. [PMID: 36575795 PMCID: PMC10111278 DOI: 10.1016/j.bpj.2022.12.029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 12/09/2022] [Accepted: 12/21/2022] [Indexed: 12/28/2022] Open
Abstract
The fusion peptide (FP) domain is necessary for the fusogenic activity of spike proteins in a variety of enveloped viruses, allowing the virus to infect the host cell, and is the only part of the protein that interacts directly with the target membrane lipid tails during fusion. There are consistent findings of poration by this domain in experimental model membrane systems, and, in certain conditions, the isolated FPs can generate pores. Here, we use molecular dynamics simulations to investigate the specifics of how these FP-induced pores form in membranes with different compositions of lysolipid and POPC. The simulations show that pores form spontaneously at high lysolipid concentrations via hybrid intermediates, where FP aggregates in the cis leaflet tilt to form a funnel-like structure that spans the leaflet and locally reduces the hydrophobic thickness that must be traversed by water to form a pore. By restraining a single FP within an FP aggregate to this tilted conformation, pores can be formed in lower-lysolipid-content membranes, including pure POPC, on the 100-ns timescale, much more rapidly than in unbiased simulations in bilayers with the same composition. The pore formation pathway is similar to the spontaneous formation in high lysolipid concentrations. Depending on the membrane composition, the pores can be metastable (as seen in POPC) or lead to membrane rupture.
Collapse
Affiliation(s)
- Amy Rice
- Laboratory of Computational Biology, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland
| | - Joshua Zimmerberg
- Section on Integrative Biophysics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland
| | - Richard W Pastor
- Laboratory of Computational Biology, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland.
| |
Collapse
|
15
|
Lee CH, Lee YY, Chang YC, Pon WL, Lee SP, Wali N, Nakazawa T, Honda Y, Shie JJ, Hsueh YP. A carnivorous mushroom paralyzes and kills nematodes via a volatile ketone. SCIENCE ADVANCES 2023; 9:eade4809. [PMID: 36652525 PMCID: PMC9848476 DOI: 10.1126/sciadv.ade4809] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Accepted: 12/16/2022] [Indexed: 05/27/2023]
Abstract
The carnivorous mushroom Pleurotus ostreatus uses an unknown toxin to rapidly paralyze and kill nematode prey upon contact. We report that small lollipop-shaped structures (toxocysts) on fungal hyphae are nematicidal and that a volatile ketone, 3-octanone, is detected in these fragile toxocysts. Treatment of Caenorhabditis elegans with 3-octanone recapitulates the rapid paralysis, calcium influx, and neuronal cell death arising from fungal contact. Moreover, 3-octanone disrupts cell membrane integrity, resulting in extracellular calcium influx into cytosol and mitochondria, propagating cell death throughout the entire organism. Last, we demonstrate that structurally related compounds are also biotoxic to C. elegans, with the length of the ketone carbon chain being crucial. Our work reveals that the oyster mushroom has evolved a specialized structure containing a volatile ketone to disrupt the cell membrane integrity of its prey, leading to rapid cell and organismal death in nematodes.
Collapse
Affiliation(s)
- Ching-Han Lee
- Institute of Molecular Biology, Academia Sinica, Taipei 11529, Taiwan
| | - Yi-Yun Lee
- Institute of Molecular Biology, Academia Sinica, Taipei 11529, Taiwan
- Molecular Cell Biology, Taiwan International Graduate Program, Academia Sinica and Graduate Institute of Life Science, National Defense Medical Center, Taipei, Taiwan
| | - Yu-Chu Chang
- Department of Biochemistry and Molecular Cell Biology, School of Medicine, Taipei Medical University, Taipei 11031, Taiwan
| | - Wen-Li Pon
- Institute of Molecular Biology, Academia Sinica, Taipei 11529, Taiwan
| | - Sue-Ping Lee
- Institute of Molecular Biology, Academia Sinica, Taipei 11529, Taiwan
| | - Niaz Wali
- Institute of Chemistry, Academia Sinica, Taipei 11529, Taiwan
- Institute of Biochemical Sciences, National Taiwan University, Taipei 10617, Taiwan
- Chemical Biology and Molecular Biophysics, Taiwan International Graduate Program, Academia Sinica, Taipei 10617, Taiwan
| | - Takehito Nakazawa
- Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Yoichi Honda
- Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Jiun-Jie Shie
- Institute of Chemistry, Academia Sinica, Taipei 11529, Taiwan
- Institute of Biochemical Sciences, National Taiwan University, Taipei 10617, Taiwan
- Chemical Biology and Molecular Biophysics, Taiwan International Graduate Program, Academia Sinica, Taipei 10617, Taiwan
| | - Yen-Ping Hsueh
- Institute of Molecular Biology, Academia Sinica, Taipei 11529, Taiwan
- Molecular Cell Biology, Taiwan International Graduate Program, Academia Sinica and Graduate Institute of Life Science, National Defense Medical Center, Taipei, Taiwan
- Department of Biochemical Science and Technology, National Taiwan University, Taipei 10617, Taiwan
- Institute of Biochemistry and Molecular Biology, College of Medicine, National Taiwan University, Taipei 10051, Taiwan
- Department of Biochemical Science and Technology, National Chiayi University, Chiayi City 60004, Taiwan
| |
Collapse
|
16
|
Ursolic Acid Impairs Cellular Lipid Homeostasis and Lysosomal Membrane Integrity in Breast Carcinoma Cells. Cells 2022; 11:cells11244079. [PMID: 36552844 PMCID: PMC9776894 DOI: 10.3390/cells11244079] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 12/02/2022] [Accepted: 12/14/2022] [Indexed: 12/23/2022] Open
Abstract
Cancer is one of the leading causes of death worldwide, thus the search for new cancer therapies is of utmost importance. Ursolic acid is a naturally occurring pentacyclic triterpene with a wide range of pharmacological activities including anti-inflammatory and anti-neoplastic effects. The latter has been assigned to its ability to promote apoptosis and inhibit cancer cell proliferation by poorly defined mechanisms. In this report, we identify lysosomes as the essential targets of the anti-cancer activity of ursolic acid. The treatment of MCF7 breast cancer cells with ursolic acid elevates lysosomal pH, alters the cellular lipid profile, and causes lysosomal membrane permeabilization and leakage of lysosomal enzymes into the cytosol. Lysosomal membrane permeabilization precedes the essential hallmarks of apoptosis placing it as an initial event in the cascade of effects induced by ursolic acid. The disruption of the lysosomal function impairs the autophagic pathway and likely partakes in the mechanism by which ursolic acid kills cancer cells. Furthermore, we find that combining treatment with ursolic acid and cationic amphiphilic drugs can significantly enhance the degree of lysosomal membrane permeabilization and cell death in breast cancer cells.
Collapse
|
17
|
Santos KP, Rodero CF, Ribeiro CM, Gremião MPD, Peccinini RG, Pavan FR, Pearce C, Gonzalez-Juarrero M, Chorilli M. Development of a Mucoadhesive Liquid Crystal System for the Administration of Rifampicin Applicable in Tuberculosis Therapy. LIFE (BASEL, SWITZERLAND) 2022; 12:life12081138. [PMID: 36013317 PMCID: PMC9409883 DOI: 10.3390/life12081138] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/19/2022] [Revised: 07/18/2022] [Accepted: 07/22/2022] [Indexed: 12/03/2022]
Abstract
Since 1966, rifampicin (RIF) has been considered one of the most potent drugs in the treatment of tuberculosis (TB), which is caused by infection with M. tuberculosis (Mtb). New nanostructured formulations for RIF delivery and alternative routes of administration have been studied as potential forms of treatment. This study evaluates a liquid crystal system for RIF delivery, using alternative drug delivery routes. The systems developed are composed of surfactant, oleylamine, and soy phosphatidylcholine. With the aid of polarized light microscopy, it was possible to determine that the developed systems had a hexagonal mesophase. All systems developed showed non-Newtonian pseudoplasticity and a high degree of thixotropy. Liquid crystal systems with RIF showed an increase in elastic potential, indicating greater mu-coadhesiveness. The evaluation of mucoadhesive forces revealed an increase in the mucoadhesive potential in the presence of mucus, indicating the presence of satisfactory mucoadhesive forces. The 9DR and 10DR liquid crystal systems, when submitted to Differential Scanning Calorimetry analysis, remained structured even at temperatures above 100 °C, showing excellent stability. The developed liquid crystal systems showed a tolerable degree of cytotoxicity and bactericidal potential, for example, the 9DR system demonstrated a reduction in bacterial load after the third day and reached zero CFU on the seventh day of the test. The developed systems were also evaluated in the preclinical model of Mtb-infected mice, using the nasal, sublingual, and cutaneous route for the delivery of RIF associated with a nanostructured liquid crystal system as a possible tool in the treatment of TB.
Collapse
Affiliation(s)
- Kaio Pini Santos
- Department of Drugs and Medicines, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara 14800-903, Brazil; (C.F.R.); (M.P.D.G.); (M.C.)
- Correspondence:
| | - Camila Fernanda Rodero
- Department of Drugs and Medicines, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara 14800-903, Brazil; (C.F.R.); (M.P.D.G.); (M.C.)
| | - Camila Maríngolo Ribeiro
- School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara 14800-903, Brazil; (C.M.R.); (R.G.P.); (F.R.P.)
| | - Maria P. D. Gremião
- Department of Drugs and Medicines, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara 14800-903, Brazil; (C.F.R.); (M.P.D.G.); (M.C.)
| | - Rosângela Gonçalves Peccinini
- School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara 14800-903, Brazil; (C.M.R.); (R.G.P.); (F.R.P.)
| | - Fernando Rogerio Pavan
- School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara 14800-903, Brazil; (C.M.R.); (R.G.P.); (F.R.P.)
| | - Camron Pearce
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology & Pathology, Colorado State University, Fort Collins, CO 80523, USA; (C.P.); (M.G.-J.)
| | - Mercedes Gonzalez-Juarrero
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology & Pathology, Colorado State University, Fort Collins, CO 80523, USA; (C.P.); (M.G.-J.)
| | - Marlus Chorilli
- Department of Drugs and Medicines, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara 14800-903, Brazil; (C.F.R.); (M.P.D.G.); (M.C.)
| |
Collapse
|
18
|
An adaptive teosinte mexicana introgression modulates phosphatidylcholine levels and is associated with maize flowering time. Proc Natl Acad Sci U S A 2022; 119:e2100036119. [PMID: 35771940 PMCID: PMC9271162 DOI: 10.1073/pnas.2100036119] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Native Americans domesticated maize (Zea mays ssp. mays) from lowland teosinte parviglumis (Zea mays ssp. parviglumis) in the warm Mexican southwest and brought it to the highlands of Mexico and South America where it was exposed to lower temperatures that imposed strong selection on flowering time. Phospholipids are important metabolites in plant responses to low-temperature and phosphorus availability and have been suggested to influence flowering time. Here, we combined linkage mapping with genome scans to identify High PhosphatidylCholine 1 (HPC1), a gene that encodes a phospholipase A1 enzyme, as a major driver of phospholipid variation in highland maize. Common garden experiments demonstrated strong genotype-by-environment interactions associated with variation at HPC1, with the highland HPC1 allele leading to higher fitness in highlands, possibly by hastening flowering. The highland maize HPC1 variant resulted in impaired function of the encoded protein due to a polymorphism in a highly conserved sequence. A meta-analysis across HPC1 orthologs indicated a strong association between the identity of the amino acid at this position and optimal growth in prokaryotes. Mutagenesis of HPC1 via genome editing validated its role in regulating phospholipid metabolism. Finally, we showed that the highland HPC1 allele entered cultivated maize by introgression from the wild highland teosinte Zea mays ssp. mexicana and has been maintained in maize breeding lines from the Northern United States, Canada, and Europe. Thus, HPC1 introgressed from teosinte mexicana underlies a large metabolic QTL that modulates phosphatidylcholine levels and has an adaptive effect at least in part via induction of early flowering time.
Collapse
|
19
|
Krawczyk HE, Rotsch AH, Herrfurth C, Scholz P, Shomroni O, Salinas-Riester G, Feussner I, Ischebeck T. Heat stress leads to rapid lipid remodeling and transcriptional adaptations in Nicotiana tabacum pollen tubes. PLANT PHYSIOLOGY 2022; 189:490-515. [PMID: 35302599 PMCID: PMC9157110 DOI: 10.1093/plphys/kiac127] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Accepted: 02/19/2022] [Indexed: 06/12/2023]
Abstract
After reaching the stigma, pollen grains germinate and form a pollen tube that transports the sperm cells to the ovule. Due to selection pressure between pollen tubes, pollen grains likely evolved mechanisms to quickly adapt to temperature changes to sustain elongation at the highest possible rate. We investigated these adaptions in tobacco (Nicotiana tabacum) pollen tubes grown in vitro under 22°C and 37°C by a multi-omics approach including lipidomic, metabolomic, and transcriptomic analysis. Both glycerophospholipids and galactoglycerolipids increased in saturated acyl chains under heat stress (HS), while triacylglycerols (TGs) changed less in respect to desaturation but increased in abundance. Free sterol composition was altered, and sterol ester levels decreased. The levels of sterylglycosides and several sphingolipid classes and species were augmented. Most amino acid levels increased during HS, including the noncodogenic amino acids γ-amino butyrate and pipecolate. Furthermore, the sugars sedoheptulose and sucrose showed higher levels. Also, the transcriptome underwent pronounced changes with 1,570 of 24,013 genes being differentially upregulated and 813 being downregulated. Transcripts coding for heat shock proteins and many transcriptional regulators were most strongly upregulated but also transcripts that have so far not been linked to HS. Transcripts involved in TG synthesis increased, while the modulation of acyl chain desaturation seemed not to be transcriptionally controlled, indicating other means of regulation. In conclusion, we show that tobacco pollen tubes are able to rapidly remodel their lipidome under HS likely by post-transcriptional and/or post-translational regulation.
Collapse
Affiliation(s)
- Hannah Elisa Krawczyk
- Department of Plant Biochemistry, Albrecht-von-Haller-Institute for Plant Sciences and Göttingen Center for Molecular Biosciences (GZMB), University of Göttingen, Göttingen 37077, Germany
| | - Alexander Helmut Rotsch
- Department of Plant Biochemistry, Albrecht-von-Haller-Institute for Plant Sciences and Göttingen Center for Molecular Biosciences (GZMB), University of Göttingen, Göttingen 37077, Germany
| | - Cornelia Herrfurth
- Department of Plant Biochemistry, Albrecht-von-Haller-Institute for Plant Sciences and Göttingen Center for Molecular Biosciences (GZMB), University of Göttingen, Göttingen 37077, Germany
- Service Unit for Metabolomics and Lipidomics, Göttingen Center for Molecular Biosciences (GZMB), University of Göttingen, Göttingen 37077, Germany
| | - Patricia Scholz
- Department of Plant Biochemistry, Albrecht-von-Haller-Institute for Plant Sciences and Göttingen Center for Molecular Biosciences (GZMB), University of Göttingen, Göttingen 37077, Germany
| | - Orr Shomroni
- NGS—Integrative Genomics Core Unit (NIG), University Medical Center Göttingen (UMG), Institute of Human Genetics, Göttingen 37077, Germany
| | - Gabriela Salinas-Riester
- NGS—Integrative Genomics Core Unit (NIG), University Medical Center Göttingen (UMG), Institute of Human Genetics, Göttingen 37077, Germany
| | - Ivo Feussner
- Department of Plant Biochemistry, Albrecht-von-Haller-Institute for Plant Sciences and Göttingen Center for Molecular Biosciences (GZMB), University of Göttingen, Göttingen 37077, Germany
- Service Unit for Metabolomics and Lipidomics, Göttingen Center for Molecular Biosciences (GZMB), University of Göttingen, Göttingen 37077, Germany
| | - Till Ischebeck
- Department of Plant Biochemistry, Albrecht-von-Haller-Institute for Plant Sciences and Göttingen Center for Molecular Biosciences (GZMB), University of Göttingen, Göttingen 37077, Germany
- Institute of Plant Biology and Biotechnology (IBBP), University of Münster, Green Biotechnology, Münster 48143, Germany
| |
Collapse
|
20
|
Dadhich R, Kapoor S. Lipidomic and Membrane Mechanical Signatures in Triple-Negative Breast Cancer: Scope for Membrane-Based Theranostics. Mol Cell Biochem 2022; 477:2507-2528. [PMID: 35595957 DOI: 10.1007/s11010-022-04459-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Accepted: 04/28/2022] [Indexed: 10/18/2022]
Abstract
Triple-negative breast cancer (TNBC) is a highly aggressive form of breast cancer associated with poor prognosis, higher grade, and a high rate of metastatic occurrence. Limited therapeutic interventions and the compounding issue of drug resistance in triple-negative breast cancer warrants the discovery of novel therapeutic targets and diagnostic modules. To this view, in addition to proteins, lipids also regulate cellular functions via the formation of membranes that modulate membrane protein function, diffusion, and their localization; thus, orchestrating signaling hot spots enriched in specific lipids/proteins on cell membranes. Lipid deregulation in cancer leads to reprogramming of the membrane dynamics and functions impacting cell proliferation, metabolism, and metastasis, providing exciting starting points for developing lipid-based approaches for treating TNBC. In this review, we provide a detailed account of specific lipidic changes in breast cancer, link the altered lipidome with membrane structure and mechanical properties, and describe how these are linked to subsequent downstream functions implicit in cancer progression, metastasis, and chemoresistance. At the fundamental level, we discuss how the lipid-centric findings in TNBC are providing cues for developing lipid-inspired theranostic strategies while bridging existing gaps in our understanding of the functional involvement of lipid membranes in cancer.
Collapse
Affiliation(s)
- Ruchika Dadhich
- Department of Chemistry, Indian Institute of Technology Bombay, Mumbai, 400076, India
| | - Shobhna Kapoor
- Department of Chemistry, Indian Institute of Technology Bombay, Mumbai, 400076, India. .,Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima, 739-8528, Japan.
| |
Collapse
|
21
|
Bashkirov PV, Kuzmin PI, Vera Lillo J, Frolov VA. Molecular Shape Solution for Mesoscopic Remodeling of Cellular Membranes. Annu Rev Biophys 2022; 51:473-497. [PMID: 35239417 PMCID: PMC10787580 DOI: 10.1146/annurev-biophys-011422-100054] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Cellular membranes self-assemble from and interact with various molecular species. Each molecule locally shapes the lipid bilayer, the soft elastic core of cellular membranes. The dynamic architecture of intracellular membrane systems is based on elastic transformations and lateral redistribution of these elementary shapes, driven by chemical and curvature stress gradients. The minimization of the total elastic stress by such redistribution composes the most basic, primordial mechanism of membrane curvature-composition coupling (CCC). Although CCC is generally considered in the context of dynamic compositional heterogeneity of cellular membrane systems, in this article we discuss a broader involvement of CCC in controlling membrane deformations. We focus specifically on the mesoscale membrane transformations in open, reservoir-governed systems, such as membrane budding, tubulation, and the emergence of highly curved sites of membrane fusion and fission. We reveal that the reshuffling of molecular shapes constitutes an independent deformation mode with complex rheological properties.This mode controls effective elasticity of local deformations as well as stationary elastic stress, thus emerging as a major regulator of intracellular membrane remodeling.
Collapse
Affiliation(s)
- Pavel V Bashkirov
- Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow, Russia
- Department of Molecular and Biological Physics, Moscow Institute of Physics and Technology, Moscow, Russia
| | - Peter I Kuzmin
- A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, Moscow, Russia
| | - Javier Vera Lillo
- Biofisika Institute (CSIC, UPV/EHU) and Department of Biochemistry and Molecular Biology, University of the Basque Country, Leioa, Spain;
| | - Vadim A Frolov
- Biofisika Institute (CSIC, UPV/EHU) and Department of Biochemistry and Molecular Biology, University of the Basque Country, Leioa, Spain;
- Ikerbasque, Basque Foundation for Science, Bilbao, Spain
| |
Collapse
|
22
|
Supported Lipid Bilayer Platform for Characterizing the Membrane-Disruptive Behaviors of Triton X-100 and Potential Detergent Replacements. Int J Mol Sci 2022; 23:ijms23020869. [PMID: 35055053 PMCID: PMC8775805 DOI: 10.3390/ijms23020869] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 01/08/2022] [Accepted: 01/12/2022] [Indexed: 02/07/2023] Open
Abstract
Triton X-100 (TX-100) is a widely used detergent to prevent viral contamination of manufactured biologicals and biopharmaceuticals, and acts by disrupting membrane-enveloped virus particles. However, environmental concerns about ecotoxic byproducts are leading to TX-100 phase out and there is an outstanding need to identify functionally equivalent detergents that can potentially replace TX-100. To date, a few detergent candidates have been identified based on viral inactivation studies, while direct mechanistic comparison of TX-100 and potential replacements from a biophysical interaction perspective is warranted. Herein, we employed a supported lipid bilayer (SLB) platform to comparatively evaluate the membrane-disruptive properties of TX-100 and a potential replacement, Simulsol SL 11W (SL-11W), and identified key mechanistic differences in terms of how the two detergents interact with phospholipid membranes. Quartz crystal microbalance-dissipation (QCM-D) measurements revealed that TX-100 was more potent and induced rapid, irreversible, and complete membrane solubilization, whereas SL-11W caused more gradual, reversible membrane budding and did not induce extensive membrane solubilization. The results further demonstrated that TX-100 and SL-11W both exhibit concentration-dependent interaction behaviors and were only active at or above their respective critical micelle concentration (CMC) values. Collectively, our findings demonstrate that TX-100 and SL-11W have distinct membrane-disruptive effects in terms of potency, mechanism of action, and interaction kinetics, and the SLB platform approach can support the development of biophysical assays to efficiently test potential TX-100 replacements.
Collapse
|
23
|
Rasmussen HØ, Otzen DE, Pedersen JS. Induction, inhibition, and incorporation: Different roles for anionic and zwitterionic lysolipids in the fibrillation of the functional amyloid FapC. J Biol Chem 2022; 298:101569. [PMID: 35007533 PMCID: PMC8888460 DOI: 10.1016/j.jbc.2022.101569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 12/29/2021] [Accepted: 12/30/2021] [Indexed: 11/16/2022] Open
Abstract
Amyloid proteins are widespread in nature both as pathological species involved in several diseases and as functional entities that can provide protection and storage for the organism. Lipids have been found in amyloid deposits from various amyloid diseases and have been shown to strongly affect the formation and structure of both pathological and functional amyloid proteins. Here, we investigate how fibrillation of the functional amyloid FapC from Pseudomonas is affected by two lysolipids, the zwitterionic lipid 1-myristoyl-2-hydroxy-sn-glycero-3-phosphocholine and the anionic lipid 1-myristoyl-2-hydroxy-sn-glycero-3-phospho-(1′-rac-glycerol) (LPG). Small-angle X-ray scattering, circular dichroism, dynamic light scattering, and thioflavin T fluorescence measurements were performed simultaneously on the same sample to ensure reproducibility and allow a multimethod integrated analysis. We found that LPG strongly induces fibrillation around its critical micelle concentration (cmc) by promoting formation of large structures, which mature via accumulation of intermediate fibril structures with a large cross section. At concentrations above its cmc, LPG strongly inhibits fibrillation by locking FapC in a core–shell complex. In contrast, lipid 1-myristoyl-2-hydroxy-sn-glycero-3-phosphocholine induces fibrillation at concentrations above its cmc, not via strong interactions with FapC but by being incorporated during fibrillation and likely stabilizing the fibrillation nucleus to reduce the lag phase. Finally, we show that LPG is not incorporated into the fibril during assembly but rather can coat the final fibril. We conclude that lipids affect both the mechanism and outcome of fibrillation of functional amyloid, highlighting a role for lipid concentration and composition in the onset and mechanism of fibrillation in vivo.
Collapse
Affiliation(s)
- Helena Østergaard Rasmussen
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Gustav Wieds Vej 14, 8000 Aarhus C, Denmark; Department of Chemistry, Aarhus University, Gustav Wieds Vej 14, 8000 Aarhus C, Denmark
| | - Daniel E Otzen
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Gustav Wieds Vej 14, 8000 Aarhus C, Denmark; Department of Molecular Biology and Genetics, Gustav Wieds Vej 14, Aarhus University, 8000 Aarhus C, Denmark.
| | - Jan Skov Pedersen
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Gustav Wieds Vej 14, 8000 Aarhus C, Denmark; Department of Chemistry, Aarhus University, Gustav Wieds Vej 14, 8000 Aarhus C, Denmark.
| |
Collapse
|
24
|
Ismail VS, Britt HM, Mosely JA, Sanderson JM. Peptide lipidation in lysophospholipid micelles and lysophospholipid-enriched membranes. Faraday Discuss 2021; 232:282-294. [PMID: 34555137 DOI: 10.1039/d1fd00030f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Acyl transfer from lipids to membrane-associated peptides is a well-documented process, leading to the generation of a lipidated peptide and a lysolipid. In this article, we demonstrate that acyl transfer from lysophosphatidylcholines (lysoPCs) to the peptide melittin also occurs, both in micelles of pure lysolipid and in lipid/lysolipid mixtures. In the case of bilayers containing lysolipids, acyl transfer from the lysolipid is marginally favoured over transfer from the lipid. In pure bilayers of saturated lipids, the introduction of even small amounts of lysolipid appears to significantly increase the reactivity towards lipidation.
Collapse
Affiliation(s)
- Vian S Ismail
- Chemistry Department, Durham University, Durham, DH1 3LE, UK.
| | - Hannah M Britt
- Chemistry Department, Durham University, Durham, DH1 3LE, UK.
| | - Jackie A Mosely
- National Horizons Centre, School of Health & Life Sciences, Teesside University, Darlington, DL1 1HG, UK.
| | | |
Collapse
|
25
|
Czolkoss S, Borgert P, Poppenga T, Hölzl G, Aktas M, Narberhaus F. Synthesis of the unusual lipid bis(monoacylglycero)phosphate in environmental bacteria. Environ Microbiol 2021; 23:6993-7008. [PMID: 34528360 DOI: 10.1111/1462-2920.15777] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 09/10/2021] [Accepted: 09/13/2021] [Indexed: 01/05/2023]
Abstract
The bacterial membrane is constantly remodelled in response to environmental conditions and the external supply of precursor molecules. Some bacteria are able to acquire exogenous lyso-phospholipids and convert them to the corresponding phospholipids. Here, we report that some soil-dwelling bacteria have alternative options to metabolize lyso-phosphatidylglycerol (L-PG). We find that the plant-pathogen Agrobacterium tumefaciens takes up this mono-acylated phospholipid and converts it to two distinct isoforms of the non-canonical lipid bis(monoacylglycero)phosphate (BMP). Chromatographic separation and quadrupole-time-of-flight MS/MS analysis revealed the presence of two possible BMP stereo configurations acylated at either of the free hydroxyl groups of the glycerol head group. BMP accumulated in the inner membrane and did not visibly alter cell morphology and growth behaviour. The plant-associated bacterium Sinorhizobium meliloti was also able to convert externally provided L-PG to BMP. Other bacteria like Pseudomonas fluorescens and Escherichia coli metabolized L-PG after cell disruption, suggesting that BMP production in the natural habitat relies both on dedicated uptake systems and on head-group acylation enzymes. Overall, our study adds two previously overlooked phospholipids to the repertoire of bacterial membrane lipids and provides evidence for the remarkable condition-responsive adaptation of bacterial membranes.
Collapse
Affiliation(s)
- Simon Czolkoss
- Microbial Biology, Ruhr University Bochum, Universitätsstraße 150, 44801 Bochum, Germany
| | - Pia Borgert
- Microbial Biology, Ruhr University Bochum, Universitätsstraße 150, 44801 Bochum, Germany
| | - Tessa Poppenga
- Microbial Biology, Ruhr University Bochum, Universitätsstraße 150, 44801 Bochum, Germany
| | - Georg Hölzl
- Institute of Molecular Physiology and Biotechnology of Plants (IMBIO), University of Bonn, Karlrobert-Kreiten-Straße 13, 53115 Bonn, Germany
| | - Meriyem Aktas
- Microbial Biology, Ruhr University Bochum, Universitätsstraße 150, 44801 Bochum, Germany
| | - Franz Narberhaus
- Microbial Biology, Ruhr University Bochum, Universitätsstraße 150, 44801 Bochum, Germany
| |
Collapse
|
26
|
Sander CL, Sears AE, Pinto AF, Choi EH, Kahremany S, Gao F, Salom D, Jin H, Pardon E, Suh S, Dong Z, Steyaert J, Saghatelian A, Skowronska-Krawczyk D, Kiser PD, Palczewski K. Nano-scale resolution of native retinal rod disk membranes reveals differences in lipid composition. J Cell Biol 2021; 220:e202101063. [PMID: 34132745 PMCID: PMC8240855 DOI: 10.1083/jcb.202101063] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 04/26/2021] [Accepted: 05/18/2021] [Indexed: 02/07/2023] Open
Abstract
Photoreceptors rely on distinct membrane compartments to support their specialized function. Unlike protein localization, identification of critical differences in membrane content has not yet been expanded to lipids, due to the difficulty of isolating domain-specific samples. We have overcome this by using SMA to coimmunopurify membrane proteins and their native lipids from two regions of photoreceptor ROS disks. Each sample's copurified lipids were subjected to untargeted lipidomic and fatty acid analysis. Extensive differences between center (rhodopsin) and rim (ABCA4 and PRPH2/ROM1) samples included a lower PC to PE ratio and increased LC- and VLC-PUFAs in the center relative to the rim region, which was enriched in shorter, saturated FAs. The comparatively few differences between the two rim samples likely reflect specific protein-lipid interactions. High-resolution profiling of the ROS disk lipid composition gives new insights into how intricate membrane structure and protein activity are balanced within the ROS, and provides a model for future studies of other complex cellular structures.
Collapse
Affiliation(s)
- Christopher L. Sander
- Department of Pharmacology, Case Western Reserve University, Cleveland, OH
- Department of Ophthalmology, Gavin Herbert Eye Institute, University of California, Irvine, Irvine, CA
| | - Avery E. Sears
- Department of Pharmacology, Case Western Reserve University, Cleveland, OH
- Department of Ophthalmology, Gavin Herbert Eye Institute, University of California, Irvine, Irvine, CA
| | - Antonio F.M. Pinto
- Clayton Foundation Laboratories for Peptide Biology, Salk Institute for Biological Studies, La Jolla, CA
| | - Elliot H. Choi
- Department of Pharmacology, Case Western Reserve University, Cleveland, OH
- Department of Ophthalmology, Gavin Herbert Eye Institute, University of California, Irvine, Irvine, CA
| | - Shirin Kahremany
- Department of Ophthalmology, Gavin Herbert Eye Institute, University of California, Irvine, Irvine, CA
| | - Fangyuan Gao
- Department of Ophthalmology, Gavin Herbert Eye Institute, University of California, Irvine, Irvine, CA
| | - David Salom
- Department of Ophthalmology, Gavin Herbert Eye Institute, University of California, Irvine, Irvine, CA
| | - Hui Jin
- Department of Pharmacology, Case Western Reserve University, Cleveland, OH
| | - Els Pardon
- Vlaams Instituut voor Biotechnologie–Vrije Universiteit Brussel Center for Structural Biology, Vlaams Instituut voor Biotechnologie, Brussels, Belgium
- Structural Biology Brussels, Vrije Universiteit Brussel, Brussels, Belgium
| | - Susie Suh
- Department of Pharmacology, Case Western Reserve University, Cleveland, OH
- Department of Ophthalmology, Gavin Herbert Eye Institute, University of California, Irvine, Irvine, CA
| | - Zhiqian Dong
- Department of Ophthalmology, Gavin Herbert Eye Institute, University of California, Irvine, Irvine, CA
| | - Jan Steyaert
- Vlaams Instituut voor Biotechnologie–Vrije Universiteit Brussel Center for Structural Biology, Vlaams Instituut voor Biotechnologie, Brussels, Belgium
- Structural Biology Brussels, Vrije Universiteit Brussel, Brussels, Belgium
| | - Alan Saghatelian
- Clayton Foundation Laboratories for Peptide Biology, Salk Institute for Biological Studies, La Jolla, CA
| | - Dorota Skowronska-Krawczyk
- Department of Ophthalmology, Gavin Herbert Eye Institute, University of California, Irvine, Irvine, CA
- Department of Physiology and Biophysics, University of California, Irvine, Irvine, CA
| | - Philip D. Kiser
- Department of Ophthalmology, Gavin Herbert Eye Institute, University of California, Irvine, Irvine, CA
- Department of Physiology and Biophysics, University of California, Irvine, Irvine, CA
- Research Service, VA Long Beach Healthcare System, Long Beach, CA
| | - Krzysztof Palczewski
- Department of Ophthalmology, Gavin Herbert Eye Institute, University of California, Irvine, Irvine, CA
- Department of Physiology and Biophysics, University of California, Irvine, Irvine, CA
- Department of Chemistry, University of California, Irvine, Irvine, CA
| |
Collapse
|
27
|
Modeling the saturation of detergent association in mixed liposome systems. Colloids Surf B Biointerfaces 2021; 206:111927. [PMID: 34216851 DOI: 10.1016/j.colsurfb.2021.111927] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 06/08/2021] [Accepted: 06/14/2021] [Indexed: 11/20/2022]
Abstract
Cells tune the lipid types present in their membranes to adjust for thermal and chemical stability, as well as to promote association and dissociation of small molecules and bound proteins. Understanding the influence of lipid type on molecule association would open doors for targeted cell therapies, in particular when molecular association is observed in the presence of competing membranes. For this reason, we modeled and experimentally observed the association of a small molecule with two membrane types present by measuring the association of the detergent Triton X-100 with two types of liposomes, egg phosphatidylcholine (ePC) liposomes and egg phosphatidic acid (ePA) liposomes, at varying ratios. We called this mixed liposomes, as each liposome population was formed from a different lipid type. Absorbance spectrometry was used to observe the stages of detergent association with mixed liposomes and to determine the detergent concentration at which the liposomes were fully saturated. A saturation model was also derived that predicts the detergent associated with each liposome type when the lipid bilayers are fully saturated with detergent. The techinical input parameters for the model are the detergent to lipid ratio and the relative absorbance intensity for each of the pure liposome species at saturation. With that, the association of detergent with any mixture of those liposome types at saturation can be determined.
Collapse
|
28
|
Pezeshkian W, Ipsen JH. Creasing of flexible membranes at vanishing tension. Phys Rev E 2021; 103:L041001. [PMID: 34005975 DOI: 10.1103/physreve.103.l041001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 03/30/2021] [Indexed: 11/07/2022]
Abstract
The properties of freestanding tensionless interfaces and membranes at low bending rigidity κ are dominated by strong fluctuations and self-avoidance and are thus outside the range of standard perturbative analysis. We analyze this regime by a simple discretized, self-avoiding membrane model on a frame subject to periodic boundary conditions by use of Monte Carlo simulation and dynamically triangulated surface techniques. We find that at low bending rigidities, the membrane properties fall into three regimes: Below the collapse transition κ_{BP} it is subject to branched polymer instability where the framed surface is not defined, in a range below a threshold rigidity κ_{c} the conformational correlation function are characterized by power-law behavior with a continuously varying exponent α, 2<α≤4 and above κ_{c}, α=4 characteristic for linearized bending excitations. Response functions specific heat and area compressibility display pronounced peaks close to κ_{c}. The results may be important for the description of soft interface systems, such as microemulsions and membranes with in-plane cooperative phenomena.
Collapse
Affiliation(s)
- Weria Pezeshkian
- Groningen Biomolecular Sciences and Biotechnology Institute and Zernike Institute for Advanced Materials, University of Groningen, Groningen, Netherlands
| | - John H Ipsen
- MEMPHYS/PhyLife, Department of Physics, Chemistry and Pharmacy (FKF), University of Southern Denmark, Campusvej 55, 5230 Odense M, Denmark
| |
Collapse
|
29
|
Amorim R, Simões ICM, Veloso C, Carvalho A, Simões RF, Pereira FB, Thiel T, Normann A, Morais C, Jurado AS, Wieckowski MR, Teixeira J, Oliveira PJ. Exploratory Data Analysis of Cell and Mitochondrial High-Fat, High-Sugar Toxicity on Human HepG2 Cells. Nutrients 2021; 13:nu13051723. [PMID: 34069635 PMCID: PMC8161147 DOI: 10.3390/nu13051723] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 05/06/2021] [Accepted: 05/17/2021] [Indexed: 12/13/2022] Open
Abstract
Non-alcoholic steatohepatitis (NASH), one of the deleterious stages of non-alcoholic fatty liver disease, remains a significant cause of liver-related morbidity and mortality worldwide. In the current work, we used an exploratory data analysis to investigate time-dependent cellular and mitochondrial effects of different supra-physiological fatty acids (FA) overload strategies, in the presence or absence of fructose (F), on human hepatoma-derived HepG2 cells. We measured intracellular neutral lipid content and reactive oxygen species (ROS) levels, mitochondrial respiration and morphology, and caspases activity and cell death. FA-treatments induced a time-dependent increase in neutral lipid content, which was paralleled by an increase in ROS. Fructose, by itself, did not increase intracellular lipid content nor aggravated the effects of palmitic acid (PA) or free fatty acids mixture (FFA), although it led to an up-expression of hepatic fructokinase. Instead, F decreased mitochondrial phospholipid content, as well as OXPHOS subunits levels. Increased lipid accumulation and ROS in FA-treatments preceded mitochondrial dysfunction, comprising altered mitochondrial membrane potential (ΔΨm) and morphology, and decreased oxygen consumption rates, especially with PA. Consequently, supra-physiological PA alone or combined with F prompted the activation of caspase pathways leading to a time-dependent decrease in cell viability. Exploratory data analysis methods support this conclusion by clearly identifying the effects of FA treatments. In fact, unsupervised learning algorithms created homogeneous and cohesive clusters, with a clear separation between PA and FFA treated samples to identify a minimal subset of critical mitochondrial markers in order to attain a feasible model to predict cell death in NAFLD or for high throughput screening of possible therapeutic agents, with particular focus in measuring mitochondrial function.
Collapse
Affiliation(s)
- Ricardo Amorim
- CNC-Center for Neuroscience and Cell Biology, CIBB-Centre for Innovative Biomedicine and Biotechnology, University of Coimbra, UC-Biotech, Biocant Park, 3060-197 Cantanhede, Portugal; (R.A.); (C.V.); (A.C.); (R.F.S.); (J.T.)
- CIQUP/Department of Chemistry and Biochemistry, Faculty of Sciences, University of Porto, 4169-007 Porto, Portugal
- PhD Programme in Experimental Biology and Biomedicine (PDBEB), Institute for Interdisciplinary Research (IIIUC), University of Coimbra, 3004-531 Coimbra, Portugal
| | - Inês C. M. Simões
- Laboratory of Mitochondrial Biology and Metabolism, Nencki Institute of Experimental Biology of Polish Academy of Sciences, 02-093 Warsaw, Poland; (I.C.M.S.); (M.R.W.)
| | - Caroline Veloso
- CNC-Center for Neuroscience and Cell Biology, CIBB-Centre for Innovative Biomedicine and Biotechnology, University of Coimbra, UC-Biotech, Biocant Park, 3060-197 Cantanhede, Portugal; (R.A.); (C.V.); (A.C.); (R.F.S.); (J.T.)
| | - Adriana Carvalho
- CNC-Center for Neuroscience and Cell Biology, CIBB-Centre for Innovative Biomedicine and Biotechnology, University of Coimbra, UC-Biotech, Biocant Park, 3060-197 Cantanhede, Portugal; (R.A.); (C.V.); (A.C.); (R.F.S.); (J.T.)
- PhD Programme in Experimental Biology and Biomedicine (PDBEB), Institute for Interdisciplinary Research (IIIUC), University of Coimbra, 3004-531 Coimbra, Portugal
| | - Rui F. Simões
- CNC-Center for Neuroscience and Cell Biology, CIBB-Centre for Innovative Biomedicine and Biotechnology, University of Coimbra, UC-Biotech, Biocant Park, 3060-197 Cantanhede, Portugal; (R.A.); (C.V.); (A.C.); (R.F.S.); (J.T.)
- PhD Programme in Experimental Biology and Biomedicine (PDBEB), Institute for Interdisciplinary Research (IIIUC), University of Coimbra, 3004-531 Coimbra, Portugal
| | - Francisco B. Pereira
- Center for Informatics and Systems, University of Coimbra, Polo II, Pinhal de Marrocos, 3030-290 Coimbra, Portugal;
- Coimbra Polytechnic-ISEC, 3030-190 Coimbra, Portugal
| | - Theresa Thiel
- Mediagnostic, D-72770 Reutlingen, Germany; (T.T.); (A.N.)
| | - Andrea Normann
- Mediagnostic, D-72770 Reutlingen, Germany; (T.T.); (A.N.)
| | - Catarina Morais
- Center for Neuroscience and Cell Biology, Department of Life Sciences, University of Coimbra, Calçada Martim de Freitas, 3000-456 Coimbra, Portugal; (C.M.); (A.S.J.)
| | - Amália S. Jurado
- Center for Neuroscience and Cell Biology, Department of Life Sciences, University of Coimbra, Calçada Martim de Freitas, 3000-456 Coimbra, Portugal; (C.M.); (A.S.J.)
| | - Mariusz R. Wieckowski
- Laboratory of Mitochondrial Biology and Metabolism, Nencki Institute of Experimental Biology of Polish Academy of Sciences, 02-093 Warsaw, Poland; (I.C.M.S.); (M.R.W.)
| | - José Teixeira
- CNC-Center for Neuroscience and Cell Biology, CIBB-Centre for Innovative Biomedicine and Biotechnology, University of Coimbra, UC-Biotech, Biocant Park, 3060-197 Cantanhede, Portugal; (R.A.); (C.V.); (A.C.); (R.F.S.); (J.T.)
- CIQUP/Department of Chemistry and Biochemistry, Faculty of Sciences, University of Porto, 4169-007 Porto, Portugal
| | - Paulo J. Oliveira
- CNC-Center for Neuroscience and Cell Biology, CIBB-Centre for Innovative Biomedicine and Biotechnology, University of Coimbra, UC-Biotech, Biocant Park, 3060-197 Cantanhede, Portugal; (R.A.); (C.V.); (A.C.); (R.F.S.); (J.T.)
- Correspondence:
| |
Collapse
|
30
|
Zheng L, Xie C, Zheng J, Dong Q, Si T, Zhang J, Hou ST. An imbalanced ratio between PC(16:0/16:0) and LPC(16:0) revealed by lipidomics supports the role of the Lands cycle in ischemic brain injury. J Biol Chem 2021; 296:100151. [PMID: 33288676 PMCID: PMC7900749 DOI: 10.1074/jbc.ra120.016565] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Revised: 12/01/2020] [Accepted: 12/06/2020] [Indexed: 12/31/2022] Open
Abstract
Promoting brain recovery after stroke is challenging as a plethora of inhibitory molecules are produced in the brain preventing it from full healing. Moreover, the full scope of inhibitory molecules produced is not well understood. Here, using a high-sensitivity UPLC-MS-based shotgun lipidomics strategy, we semiquantitively measured the differential lipid contents in the mouse cerebral cortex recovering from a transient middle cerebral artery occlusion (MCAO). The lipidomic data were interrogated using the soft independent modeling of class analogy (SIMCA) method involving principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA). Statistics of the 578 confirmed lipids revealed 84 species were differentially changed during MCAO/reperfusion. The most dynamic changes in lipids occurred between 1 and 7 days post-MCAO, whereas concentrations had subsided to the Sham group level at 14 and 28 days post-MCAO. Quantitative analyses revealed a strong monotonic relationship between the reduction in phosphatidylcholine (PC)(16:0/16:0) and the increase in lysophosphatidylcholine (LPC)(16:0) levels (Spearman's Rs = -0.86) during the 1 to 7 days reperfusion period. Inhibition of cPLA2 prevented changes in the ratio between PC(16:0/16:0) and LPC(16:0), indicating altered Land's cycle of PC. A series of in vitro studies showed that LPC(16:0), but not PC(16:0/16:0), was detrimental to the integrity of neuronal growth cones and neuronal viability through evoking intracellular calcium influx. In contrast, PC(16:0/16:0) significantly suppressed microglial secretion of IL-1β and TNF-α, limiting neuroinflammation pathways. Together, these data support the role of the imbalanced ratio between PC(16:0/16:0) and LPC(16:0), maintained by Lands' cycle, in neuronal damage and microglia-mediated inflammatory response during ischemic recovery.
Collapse
Affiliation(s)
- Lifeng Zheng
- Brain Research Centre and Department of Biology, Southern University of Science and Technology, Shenzhen, Guangdong Province, China
| | - Chengbin Xie
- Brain Research Centre and Department of Biology, Southern University of Science and Technology, Shenzhen, Guangdong Province, China
| | - Ju Zheng
- Brain Research Centre and Department of Biology, Southern University of Science and Technology, Shenzhen, Guangdong Province, China
| | - Qiangrui Dong
- Brain Research Centre and Department of Biology, Southern University of Science and Technology, Shenzhen, Guangdong Province, China
| | - Tengxiao Si
- Brain Research Centre and Department of Biology, Southern University of Science and Technology, Shenzhen, Guangdong Province, China
| | - Jing Zhang
- Brain Research Centre and Department of Biology, Southern University of Science and Technology, Shenzhen, Guangdong Province, China
| | - Sheng-Tao Hou
- Brain Research Centre and Department of Biology, Southern University of Science and Technology, Shenzhen, Guangdong Province, China; Department of Biochemistry, Microbiology, and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada.
| |
Collapse
|
31
|
Affiliation(s)
- Chandra Has
- Department of Chemical Engineering, Indian Institute of Technology Bombay, Mumbai, India
| |
Collapse
|
32
|
Szlasa W, Zendran I, Zalesińska A, Tarek M, Kulbacka J. Lipid composition of the cancer cell membrane. J Bioenerg Biomembr 2020; 52:321-342. [PMID: 32715369 PMCID: PMC7520422 DOI: 10.1007/s10863-020-09846-4] [Citation(s) in RCA: 177] [Impact Index Per Article: 44.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Accepted: 07/10/2020] [Indexed: 12/12/2022]
Abstract
Cancer cell possesses numerous adaptations to resist the immune system response and chemotherapy. One of the most significant properties of the neoplastic cells is the altered lipid metabolism, and consequently, the abnormal cell membrane composition. Like in the case of phosphatidylcholine, these changes result in the modulation of certain enzymes and accumulation of energetic material, which could be used for a higher proliferation rate. The changes are so prominent, that some lipids, such as phosphatidylserines, could even be considered as the cancer biomarkers. Additionally, some changes of biophysical properties of cell membranes lead to the higher resistance to chemotherapy, and finally to the disturbances in signalling pathways. Namely, the increased levels of certain lipids, like for instance phosphatidylserine, lead to the attenuation of the immune system response. Also, changes in lipid saturation prevent the cells from demanding conditions of the microenvironment. Particularly interesting is the significance of cell membrane cholesterol content in the modulation of metastasis. This review paper discusses the roles of each lipid type in cancer physiology. The review combined theoretical data with clinical studies to show novel therapeutic options concerning the modulation of cell membranes in oncology.
Collapse
Affiliation(s)
- Wojciech Szlasa
- Faculty of Medicine, Wroclaw Medical University, Wrocław, Poland
| | - Iga Zendran
- Faculty of Medicine, Wroclaw Medical University, Wrocław, Poland
| | | | - Mounir Tarek
- Université de Lorraine, CNRS, LPCT, F-54000, Nancy, France
| | - Julita Kulbacka
- Department of Molecular and Cellular Biology, Faculty of Pharmacy, Wroclaw Medical University, Wrocław, Poland.
| |
Collapse
|
33
|
Drzazga A, Cichońska E, Koziołkiewicz M, Gendaszewska-Darmach E. Formation of βTC3 and MIN6 Pseudoislets Changes the Expression Pattern of Gpr40, Gpr55, and Gpr119 Receptors and Improves Lysophosphatidylcholines-Potentiated Glucose-Stimulated Insulin Secretion. Cells 2020; 9:E2062. [PMID: 32917053 PMCID: PMC7565006 DOI: 10.3390/cells9092062] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 09/01/2020] [Accepted: 09/08/2020] [Indexed: 02/06/2023] Open
Abstract
The impaired spatial arrangement and connections between cells creating islets of Langerhans as well as altered expression of G protein-coupled receptors (GPCRs) often lead to dysfunction of insulin-secreting pancreatic β cells and can significantly contribute to the development of diabetes. Differences in glucose-stimulated insulin secretion (GSIS) are noticeable not only in diabetic individuals but also in model pancreatic β cells, e.g., βTC3 and MIN6 β cell lines with impaired and normal insulin secretion, respectively. Now, we compare the ability of GPCR agonists (lysophosphatidylcholines bearing fatty acid chains of different lengths) to potentiate GSIS in βTC3 and MIN6 β cell models, cultured as adherent monolayers and in a form of pseudoislets (PIs) with pancreatic MS1 endothelial cells. Our aim was also to investigate differences in expression of the GPCRs responsive to LPCs in these experimental systems. Aggregation of β cells into islet-like structures greatly enhanced the expression of Gpr40, Gpr55, and Gpr119 receptors. In contrast, the co-culture of βTC3 cells with endothelial cells converted the GPCR expression pattern closer to the pattern observed in MIN6 cells. Additionally, the efficiencies of various LPC species in βTC3-MS1 PIs also shifted toward the MIN6 cell model.
Collapse
Affiliation(s)
- Anna Drzazga
- Institute of Molecular and Industrial Biotechnology, Faculty of Biotechnology and Food Sciences, Lodz University of Technology, Stefanowskiego 4/10, 90-924 Lodz, Poland; (E.C.); (M.K.)
| | | | | | - Edyta Gendaszewska-Darmach
- Institute of Molecular and Industrial Biotechnology, Faculty of Biotechnology and Food Sciences, Lodz University of Technology, Stefanowskiego 4/10, 90-924 Lodz, Poland; (E.C.); (M.K.)
| |
Collapse
|
34
|
Concentration-Dependent Effects of N-3 Long-Chain Fatty Acids on Na,K-ATPase Activity in Human Endothelial Cells. Molecules 2019; 25:molecules25010128. [PMID: 31905689 PMCID: PMC6982972 DOI: 10.3390/molecules25010128] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Revised: 12/20/2019] [Accepted: 12/25/2019] [Indexed: 11/17/2022] Open
Abstract
N-3 eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) seem to prevent endothelial dysfunction, a crucial step in atherogenesis, by modulating the levels of vasoactive molecules and by influencing Na,K-ATPase activity of vascular myocytes. The activity of endothelial Na,K-ATPase controls the ionic homeostasis of the neighboring cells, as well as cell function. However, controversy exists with respect to the vascular protective effect of EPA and DHA. We argue that this dispute might be due to the use of different concentrations of EPA and DHA in different studies. Therefore, this study was designed to define an optimal concentration of EPA and DHA to investigate endothelial function. For this purpose, human endothelial cells were exposed for 24 h to different concentrations of DHA or EPA (0–20 μM) to study membrane fluidity, peroxidation potential and Na,K-ATPase activity. EPA and DHA were linearly incorporated and this incorporation was mirrored by the linear increase of unsaturation index, membrane fluidity, and peroxidation potential. Na,K-ATPase activity peaked at 3.75 μM of EPA and DHA and then gradually decreased. It is noteworthy that DHA effects were always more pronounced than EPA. Concluding, low concentrations of EPA and DHA minimize peroxidation sensitivity and optimize Na,K-ATPase activity.
Collapse
|
35
|
Pezeshkian W, Ipsen JH. Fluctuations and conformational stability of a membrane patch with curvature inducing inclusions. SOFT MATTER 2019; 15:9974-9981. [PMID: 31754667 DOI: 10.1039/c9sm01762c] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Membranes with curvature inducing inclusions display a range of cooperative phenomena, which can be linked to biomembrane function, e.g. membrane tubulation, vesiculation, softening and spontaneous tension. We investigate how these phenomena are related for a fluctuating, framed membrane through analysis of a descretized membrane model by Monte Carlo simulation techniques. The membrane model is based on a dynamically triangulated surface equipped with non-interacting, up-down symmetry breaking inclusions where only terms coupled linearly to mean-curvature are maintained. We show that the lateral configurational entropy plays a key role for the mechanical properties of the semi-flexible membrane, e.g. a pronounced softening at intermediate inclusion coverages of the membrane and generation of membrane tension. Tensionless framed membranes will remain quasi-flat up to some threshold coverage, where a shape instability occurs with formation of pearling or tubular membranes, which below full coverage is associated with segregation of inclusions between the curved and flat membrane geometries. For inclusions with preference for highly curved membranes the instability appears at dilute inclusion coverages and is accompanied by strong configurational fluctuations.
Collapse
Affiliation(s)
- Weria Pezeshkian
- Groningen Biomolecular Sciences and Biotechnology Institute and Zernike Institute for Advanced Materials, University of Groningen, Groningen, The Netherlands.
| | | |
Collapse
|
36
|
Clark ST, Arras MML, Sarles SA, Frymier PD. Lipid shape determination of detergent solubilization in mixed-lipid liposomes. Colloids Surf B Biointerfaces 2019; 187:110609. [PMID: 31806354 DOI: 10.1016/j.colsurfb.2019.110609] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Revised: 09/17/2019] [Accepted: 10/21/2019] [Indexed: 11/16/2022]
Abstract
The effects of lipid charge and head group size on liposome partitioning by detergents is an important consideration for applications such as liposomal drug delivery or proteoliposome formation. Yet, the solubilization of mixed-lipid liposomes, those containing multiple types of lipids, by detergents has received insufficient attention. This study examines the incorporation into and subsequent dissolution of mixed-lipid liposomes comprised of both egg phosphatidylcholine (ePC) and egg phosphatidic acid (ePA) by the detergent Triton-X100 (TX). Liposomes were prepared with mixtures of the two lipids, ePC and ePA, at molar ratios from 0 to 1, then step-wise solubilized with TX. Changes in turbidity, size distribution, and molar heat power at constant temperature throughout the solubilization process were assessed. The data suggest that the difference in lipid shapes (shape factors = 0.74 and 1.4 [1,2]) affects packing in membranes, and hence influences how much TX can be incorporated before disruption. As such, liposomes containing the observed ratios of ePA incorporated higher concentrations of TX before initiating dissolution into detergent and lipid mixed-micelles. The cause was concluded to be increased mismatching in the bilayer from the conical shape of ePA compared to the cylindrical shape of ePC. Additionally, the degree to which ePA is approximated as conical versus cylindrical was modulated with pH. It was confirmed that less conical ePA behaved more similarly to ePC than more conical ePA. The understanding gained here on lipid shape in liposome incorporation of TX enables research to use in vitro liposomes that more closely mimic native membranes.
Collapse
Affiliation(s)
- Samantha T Clark
- Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, 1512 Middle Dr, Knoxville, TN 37996, USA
| | - Matthias M L Arras
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Stephen A Sarles
- Department of Mechanical, Aerospace, and Biomedical Engineering, University of Tennessee, 1512 Middle Drive, 414 Dougherty Engineering Building, Knoxville, TN 37996, USA
| | - Paul D Frymier
- Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, 1512 Middle Dr, Knoxville, TN 37996, USA.
| |
Collapse
|
37
|
Abstract
Formation of a transport vesicle in membrane trafficking pathways requires deformation of the membrane to form a highly curved structure. A recent study reveals a crucial function for the conical lipid lysophosphatidylinositol in reducing the bending rigidity of the membrane during COPII vesicle budding in the early secretory pathway.
Collapse
|
38
|
Heinrich P, Braunbeck T. Bioavailability of microplastic-bound pollutants in vitro: The role of adsorbate lipophilicity and surfactants. Comp Biochem Physiol C Toxicol Pharmacol 2019; 221:59-67. [PMID: 30940555 DOI: 10.1016/j.cbpc.2019.03.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Revised: 03/25/2019] [Accepted: 03/27/2019] [Indexed: 11/30/2022]
Abstract
The potential role of microplastic particles (MPs) as vectors for lipophilic organic pollutants enhancing their uptake by organisms has repeatedly been discussed in the scientific community. Likewise, several studies indicate an important role of surfactants in pollutant-transfer from MP to organisms. Employing polyethylene particles, the bioavailability of three MP-bound inducers of 7-ethoxyresorufin-O-deethylase (EROD) with variable lipophilicity was quantitatively compared via EROD activity in RTL-W1 cells. In addition, non-cytotoxic surfactant concentrations of Pluronic F-127, rhamnolipids, sodium deoxycholate and sodium dodecyl sulfate (SDS) supplemented to the medium were tested for their effects on pollutant desorption from MPs as well as on cellular EROD induction. Bioavailability of MP-bound pollutants was negatively correlated with lipophilicity, and all surfactants were found to modulate the cellular response towards inducers by unidentified mechanisms. After experimental correction for effects on the cellular response, all surfactants except SDS moderately increased desorption of inducer from MPs. Results on the impact of lipophilicity agree with previously published thermodynamic models, indicating that appreciable pollutant desorption from MPs may only occur for substances with comparatively low lipophilicity, the accumulation of which on MPs is negligible in the environment. However, the role of surfactants should be considered further with respect to potential effects on sorption of pollutants to and from MPs.
Collapse
Affiliation(s)
- Patrick Heinrich
- Aquatic Ecology and Toxicology Section, Centre for Organismal Studies, University of Heidelberg, Im Neuenheimer Feld 504, D-69120 Heidelberg, Germany.
| | - Thomas Braunbeck
- Aquatic Ecology and Toxicology Section, Centre for Organismal Studies, University of Heidelberg, Im Neuenheimer Feld 504, D-69120 Heidelberg, Germany
| |
Collapse
|
39
|
Functional Reconstitution of HlyB, a Type I Secretion ABC Transporter, in Saposin-A Nanoparticles. Sci Rep 2019; 9:8436. [PMID: 31182729 PMCID: PMC6558041 DOI: 10.1038/s41598-019-44812-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2018] [Accepted: 05/23/2019] [Indexed: 11/08/2022] Open
Abstract
Type I secretion systems (T1SS) are ubiquitous transport machineries in Gram-negative bacteria. They comprise a relatively simple assembly of three membrane-localised proteins: an inner-membrane complex composed of an ABC transporter and a membrane fusion protein, and a TolC-like outer membrane component. T1SS transport a wide variety of substrates with broad functional diversity. The ABC transporter hemolysin B (HlyB), for example, is part of the hemolysin A-T1SS in Escherichia coli. In contrast to canonical ABC transporters, an accessory domain, a C39 peptidase-like domain (CLD), is located at the N-terminus of HlyB and is essential for secretion. In this study, we have established an optimised purification protocol for HlyB and the subsequent reconstitution employing the saposin-nanoparticle system. We point out the negative influence of free detergent on the basal ATPase activity of HlyB, studied the influence of a lysolipid or lipid matrix on activity and present functional studies with the full-length substrate proHlyA in its folded and unfolded states, which both have a stimulatory effect on the ATPase activity.
Collapse
|
40
|
Funato K, Riezman H, Muñiz M. Vesicular and non-vesicular lipid export from the ER to the secretory pathway. Biochim Biophys Acta Mol Cell Biol Lipids 2019; 1865:158453. [PMID: 31054928 DOI: 10.1016/j.bbalip.2019.04.013] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Revised: 12/20/2018] [Accepted: 01/06/2019] [Indexed: 11/26/2022]
Abstract
The endoplasmic reticulum is the site of synthesis of most glycerophospholipids, neutral lipids and the initial steps of sphingolipid biosynthesis of the secretory pathway. After synthesis, these lipids are distributed within the cells to create and maintain the specific compositions of the other secretory organelles. This represents a formidable challenge, particularly while there is a simultaneous and quantitatively important flux of membrane components stemming from the vesicular traffic of proteins through the pathway, which can also vary depending on the cell type and status. To meet this challenge cells have developed an intricate system of interorganellar contacts and lipid transport proteins, functioning in non-vesicular lipid transport, which are able to ensure membrane lipid homeostasis even in the absence of membrane trafficking. Nevertheless, under normal conditions, lipids are transported in cells by both vesicular and non-vesicular mechanisms. In this review we will discuss the mechanism and roles of vesicular and non-vesicular transport of lipids from the ER to other organelles of the secretory pathway.
Collapse
Affiliation(s)
- Kouichi Funato
- Department of Bioresource Science and Technology, Hiroshima University, Japan.
| | - Howard Riezman
- NCCR Chemical Biology and Department of Biochemistry, Sciences II, University of Geneva, Switzerland.
| | - Manuel Muñiz
- Department of Cell Biology, University of Seville, 41012 Seville, Spain; Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Spain.
| |
Collapse
|
41
|
Wang Y, Mousley CJ, Lete MG, Bankaitis VA. An equal opportunity collaboration between lipid metabolism and proteins in the control of membrane trafficking in the trans-Golgi and endosomal systems. Curr Opin Cell Biol 2019; 59:58-72. [PMID: 31039522 DOI: 10.1016/j.ceb.2019.03.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 03/25/2019] [Accepted: 03/27/2019] [Indexed: 12/18/2022]
Abstract
Recent years have witnessed the evolution of the cell biology of lipids into an extremely active area of investigation. Deciphering the involvement of lipid metabolism and lipid signaling in membrane trafficking pathways defines a major nexus of contemporary experimental activity on this front. Significant effort in that direction is invested in understanding the trans-Golgi network/endosomal system where unambiguous connections between membrane trafficking and inositol lipid and phosphatidylcholine metabolism were first discovered. However, powered by new advances in contemporary cell biology, the march of science is rapidly expanding that window of inquiry to include ever more diverse arms of the lipid metabolome, and to include other compartments of the secretory pathway as well.
Collapse
Affiliation(s)
- Yaxi Wang
- Department of Biochemistry & Biophysics, Texas A&M University, College Station, TX 77843-2128, USA
| | - Carl J Mousley
- School of Biomedical Sciences, Curtin Health Innovation Research Institute (CHIRI), Faculty of Health Sciences, Curtin University, Bentley, WA 6102, Australia
| | - Marta G Lete
- Department of Molecular and Cellular Medicine, Texas A&M Health Science Center, College Station, TX 77843-1114, USA
| | - Vytas A Bankaitis
- Department of Biochemistry & Biophysics, Texas A&M University, College Station, TX 77843-2128, USA; Department of Molecular and Cellular Medicine, Texas A&M Health Science Center, College Station, TX 77843-1114, USA.
| |
Collapse
|
42
|
Engel KM, Baumann S, Rolle-Kampczyk U, Schiller J, von Bergen M, Grunewald S. Metabolomic profiling reveals correlations between spermiogram parameters and the metabolites present in human spermatozoa and seminal plasma. PLoS One 2019; 14:e0211679. [PMID: 30785892 PMCID: PMC6382115 DOI: 10.1371/journal.pone.0211679] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Accepted: 01/20/2019] [Indexed: 01/07/2023] Open
Abstract
In 50% of all infertility cases, the male is subfertile or infertile, however, the underlying mechanisms are often unknown. Even when assisted reproductive procedures such as in vitro fertilization and intracytoplasmic sperm injection are performed, the causes of male factor infertility frequently remain elusive. Since the overall activity of cells is closely linked to their metabolic capacity, we analyzed a panel of 180 metabolites in human sperm and seminal plasma and elucidated their associations with spermiogram parameters. Therefore, metabolites from a group of 20 healthy donors were investigated using a targeted LC-MS/MS approach. The correlation analyses of the amino acids, biogenic amines, acylcarnitines, lysophosphatidylcholines, phosphatidylcholines, sphingomyelins and sugars from sperm and seminal plasma with standard spermiogram parameters revealed that metabolites in sperm are closely related to sperm motility, whereas those in seminal plasma are closely related to sperm concentration and morphology. This study provides essential insights into the metabolome of human sperm and seminal plasma and its associations with sperm functions. This metabolomics technique could be a promising screening tool to detect the factors of male infertility in cases where the cause of infertility is unclear.
Collapse
Affiliation(s)
- Kathrin M. Engel
- Training Center of the European Academy of Andrology (EAA), Dermatology, Venerology and Allergology Clinic, University Hospital Leipzig, Leipzig, Germany
- Institute of Medical Physics and Biophysics, Faculty of Medicine, University of Leipzig, Leipzig, Germany
| | - Sven Baumann
- Department of Molecular Systems Biology, Helmholtz Centre for Environmental Research – UFZ, Leipzig, Germany
| | - Ulrike Rolle-Kampczyk
- Department of Molecular Systems Biology, Helmholtz Centre for Environmental Research – UFZ, Leipzig, Germany
| | - Jürgen Schiller
- Institute of Medical Physics and Biophysics, Faculty of Medicine, University of Leipzig, Leipzig, Germany
| | - Martin von Bergen
- Department of Molecular Systems Biology, Helmholtz Centre for Environmental Research – UFZ, Leipzig, Germany
- Institute of Biochemistry, Faculty of Life Sciences, University of Leipzig, Leipzig, Germany
| | - Sonja Grunewald
- Training Center of the European Academy of Andrology (EAA), Dermatology, Venerology and Allergology Clinic, University Hospital Leipzig, Leipzig, Germany
- * E-mail:
| |
Collapse
|
43
|
Lebecque S, Lins L, Dayan FE, Fauconnier ML, Deleu M. Interactions Between Natural Herbicides and Lipid Bilayers Mimicking the Plant Plasma Membrane. FRONTIERS IN PLANT SCIENCE 2019; 10:329. [PMID: 30936889 PMCID: PMC6431664 DOI: 10.3389/fpls.2019.00329] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Accepted: 02/28/2019] [Indexed: 05/06/2023]
Abstract
Natural phytotoxic compounds could become an alternative to traditional herbicides in the framework of sustainable agriculture. Nonanoic acid, sarmentine and sorgoleone are such molecules extracted from plants and able to inhibit the growth of various plant species. However, their mode of action is not fully understood and despite clues indicating that they could affect the plant plasma membrane, molecular details of such phenomenon are lacking. In this paper, we investigate the interactions between those natural herbicides and artificial bilayers mimicking the plant plasma membrane. First, their ability to affect lipid order and fluidity is evaluated by means of fluorescence measurements. It appears that sorgoleone has a clear ordering effect on lipid bilayers, while nonanoic acid and sarmentine induce no or little change to these parameters. Then, a thermodynamic characterization of interactions of each compound with lipid vesicles is obtained with isothermal titration calorimetry, and their respective affinity for bilayers is found to be ranked as follows: sorgoleone > sarmentine > nonanoic acid. Finally, molecular dynamics simulations give molecular details about the location of each compound within a lipid bilayer and confirm the rigidifying effect of sorgoleone. Data also suggest that mismatch in alkyl chain length between nonanoic acid or sarmentine and lipid hydrophobic tails could be responsible for bilayer destabilization. Results are discussed regarding their implications for the phytotoxicity of these compounds.
Collapse
Affiliation(s)
- Simon Lebecque
- TERRA, Laboratory of Molecular Biophysics at Interfaces, Gembloux Agro-Bio Tech, University of Liège, Gembloux, Belgium
- TERRA – AgricultureIsLife, Gembloux Agro-Bio Tech, University of Liège, Gembloux, Belgium
| | - Laurence Lins
- TERRA, Laboratory of Molecular Biophysics at Interfaces, Gembloux Agro-Bio Tech, University of Liège, Gembloux, Belgium
| | - Franck E. Dayan
- Department of Bioagricultural Sciences and Pest Management, Colorado State University, Fort Collins, CO, United States
| | - Marie-Laure Fauconnier
- General and Organic Chemistry Laboratory, Gembloux Agro-Bio Tech, University of Liège, Gembloux, Belgium
| | - Magali Deleu
- TERRA, Laboratory of Molecular Biophysics at Interfaces, Gembloux Agro-Bio Tech, University of Liège, Gembloux, Belgium
- *Correspondence: Magali Deleu,
| |
Collapse
|
44
|
Canul-Sánchez JA, Hernández-Araiza I, Hernández-García E, Llorente I, Morales-Lázaro SL, Islas LD, Rosenbaum T. Different agonists induce distinct single-channel conductance states in TRPV1 channels. J Gen Physiol 2018; 150:1735-1746. [PMID: 30409787 PMCID: PMC6279355 DOI: 10.1085/jgp.201812141] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 09/20/2018] [Accepted: 10/16/2018] [Indexed: 11/20/2022] Open
Abstract
TRPV1 is a polymodal ion channel that can be activated by lysophosphatidic acid (LPA), resulting in pain. Here we show that TRPV1 activation by LPA promotes a distinct open state with a different single-channel conductance from that induced by capsaicin. The TRPV1 ion channel is a membrane protein that is expressed in primary afferent nociceptors, where it is activated by a diverse array of stimuli. Our prior work has shown that this channel is activated by lysophosphatidic acid (LPA), an unsaturated lysophospholipid that is produced endogenously and released under certain pathophysiological conditions, resulting in the sensation of pain. Macroscopic currents activated by saturating concentrations of LPA applied to excised membrane patches are larger in magnitude than those activated by saturating concentrations of capsaicin, which causes near-maximal TRPV1 open probability. Here we show that activation of TRPV1 by LPA is associated with a higher single-channel conductance than activation by capsaicin. We also observe that the effects of LPA on TRPV1 are not caused by an increase in the surface charge nor are they mimicked by a structurally similar lipid, ruling out the contribution of change in membrane properties. Finally, we demonstrate that the effects of LPA on the unitary conductance of TRPV1 depend upon the presence of a positively charged residue in the C terminus of the channel, suggesting that LPA induces a distinct conformational change.
Collapse
Affiliation(s)
- Jesús Aldair Canul-Sánchez
- Departamento de Neurociencia Cognitiva, División Neurociencias, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, México City, México
| | - Ileana Hernández-Araiza
- Departamento de Neurociencia Cognitiva, División Neurociencias, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, México City, México
| | - Enrique Hernández-García
- Departamento de Neurociencia Cognitiva, División Neurociencias, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, México City, México
| | - Itzel Llorente
- Departamento de Neurociencia Cognitiva, División Neurociencias, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, México City, México
| | - Sara L Morales-Lázaro
- Departamento de Neurociencia Cognitiva, División Neurociencias, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, México City, México
| | - León D Islas
- Departamento de Fisiología, Facultad de Medicina, Universidad Nacional Autónoma de México, México City, México
| | - Tamara Rosenbaum
- Departamento de Neurociencia Cognitiva, División Neurociencias, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, México City, México
| |
Collapse
|
45
|
Allolio C, Haluts A, Harries D. A local instantaneous surface method for extracting membrane elastic moduli from simulation: Comparison with other strategies. Chem Phys 2018. [DOI: 10.1016/j.chemphys.2018.03.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
|
46
|
Rondelli V, Del Favero E, Brocca P, Fragneto G, Trapp M, Mauri L, Ciampa M, Romani G, Braun C, Winterstein L, Schroeder I, Thiel G, Moroni A, Cantu' L. Directional K+ channel insertion in a single phospholipid bilayer: Neutron reflectometry and electrophysiology in the joint exploration of a model membrane functional platform. Biochim Biophys Acta Gen Subj 2018; 1862:1742-1750. [DOI: 10.1016/j.bbagen.2018.05.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 04/27/2018] [Accepted: 05/07/2018] [Indexed: 01/05/2023]
|
47
|
Melero A, Chiaruttini N, Karashima T, Riezman I, Funato K, Barlowe C, Riezman H, Roux A. Lysophospholipids Facilitate COPII Vesicle Formation. Curr Biol 2018; 28:1950-1958.e6. [PMID: 29887313 PMCID: PMC6013297 DOI: 10.1016/j.cub.2018.04.076] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Revised: 03/05/2018] [Accepted: 04/24/2018] [Indexed: 12/15/2022]
Abstract
Coat protein complex II (COPII) proteins form vesicles from the endoplasmic reticulum to export cargo molecules to the Golgi apparatus. Among the many proteins involved in this process, Sec12 is a key regulator, functioning as the guanosine diphosphate (GDP) exchange factor for Sar1p, the small guanosine triphosphatase (GTPase) that initiates COPII assembly. Here we show that overexpression of phospholipase B3 in the thermosensitive sec12-4 mutant partially restores growth and protein transport at non-permissive temperatures. Lipidomics analyses of these cells show a higher content of lysophosphatidylinositol (lysoPI), consistent with the lipid specificity of PLB3. Furthermore, we show that lysoPI is specifically enriched in COPII vesicles isolated from in vitro budding assays. As these results suggested that lysophospholipids could facilitate budding under conditions of defective COPII coat dynamics, we reconstituted COPII binding onto giant liposomes with purified proteins and showed that lysoPI decreases membrane rigidity and enhances COPII recruitment to liposomes. Our results support a mechanical facilitation of COPII budding by lysophospholipids. COPII mutant sec12-4 is rescued by the overexpression of an ER resident phospholipase Lipidomic analysis of COPII vesicles shows enrichment in lysophospholipids Recruitment of COPII proteins to liposomes increases in presence of lysophospholipids Lysophosphatidylinositol lowers the rigidity of membranes in vitro
Collapse
Affiliation(s)
- Alejandro Melero
- Department of Biochemistry, University of Geneva, 1211 Geneva, Switzerland; Swiss National Centre for Competence in Research in Chemical Biology, 1211 Geneva, Switzerland
| | | | - Takefumi Karashima
- Department of Bioresource Science and Technology, Hiroshima University, Hiroshima 739-8528, Japan
| | - Isabelle Riezman
- Department of Biochemistry, University of Geneva, 1211 Geneva, Switzerland
| | - Kouichi Funato
- Department of Bioresource Science and Technology, Hiroshima University, Hiroshima 739-8528, Japan
| | - Charles Barlowe
- Department of Biochemistry, Geisel School of Medicine at Dartmouth, Hanover, NH 03755-3844, USA
| | - Howard Riezman
- Department of Biochemistry, University of Geneva, 1211 Geneva, Switzerland; Swiss National Centre for Competence in Research in Chemical Biology, 1211 Geneva, Switzerland.
| | - Aurélien Roux
- Department of Biochemistry, University of Geneva, 1211 Geneva, Switzerland; Swiss National Centre for Competence in Research in Chemical Biology, 1211 Geneva, Switzerland.
| |
Collapse
|
48
|
Micelles with ultralow critical micelle concentration as carriers for drug delivery. Nat Biomed Eng 2018; 2:318-325. [PMID: 30936455 DOI: 10.1038/s41551-018-0234-x] [Citation(s) in RCA: 157] [Impact Index Per Article: 26.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Accepted: 04/05/2018] [Indexed: 12/27/2022]
Abstract
Conventional micellar carriers disassemble into free surfactants when diluted at concentrations below the critical micelle concentration (CMC). This limits the bioavailability in vivo of injected hydrophobic drugs encapsulated in micellar systems. Here, we show that a micelle comprising a superhydrophilic zwitterionic polymer domain and a superhydrophobic lipid domain has an undetectable CMC below 10-6 mM-a value that is orders of magnitude lower than the CMCs (>10-3 mM) of typical micellar systems. We also show that zwitterionic moieties or zwitterionic polymers added to a micelle solution stabilize the micelles at concentrations below their inherent CMC. In a mouse model of melanoma, ultralow-CMC micelles encapsulating docetaxel led to the complete eradication of tumours, whereas conventional docetaxel micellar formulations did not reverse tumour growth. Ultralow-CMC micelles might become next-generation carriers for drug delivery.
Collapse
|
49
|
Petty HR. Frontiers of Complex Disease Mechanisms: Membrane Surface Tension May Link Genotype to Phenotype in Glaucoma. Front Cell Dev Biol 2018; 6:32. [PMID: 29682502 PMCID: PMC5897435 DOI: 10.3389/fcell.2018.00032] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Accepted: 03/13/2018] [Indexed: 12/19/2022] Open
Abstract
Although many monogenic diseases are understood based upon structural changes of gene products, less progress has been made concerning polygenic disease mechanisms. This article presents a new interdisciplinary approach to understand complex diseases, especially their genetic polymorphisms. I focus upon primary open angle glaucoma (POAG). Although elevated intraocular pressure (IOP) and oxidative stress are glaucoma hallmarks, the linkages between these factors and cell death are obscure. Reactive oxygen species (ROS) promote the formation of oxidatively truncated phosphoglycerides (OTP), free fatty acids, lysophosphoglycerides, oxysterols, and other chemical species that promote membrane disruption and decrease membrane surface tension. Several POAG-linked gene polymorphisms identify proteins that manage damaged lipids and/or influence membrane surface tension. POAG-related genes expected to participate in these processes include: ELOVL5, ABCA1, APOE4, GST, CYP46A1, MYOC, and CAV. POAG-related gene products are expected to influence membrane surface tension, strength, and repair. I propose that heightened IOP overcomes retinal ganglion cell (RGC) membrane compressive strength, weakened by damaged lipid accumulation, to form pores. The ensuing structural failure promotes apoptosis and blindness. The linkage between glaucoma genotype and phenotype is mediated by physical events. Force balancing between the IOP and compressive strength regulates pore nucleation; force balancing between pore line tension and membrane surface tension regulates pore growth. Similar events may contribute to traumatic brain injury, Alzheimer's disease, and macular degeneration.
Collapse
Affiliation(s)
- Howard R Petty
- Department of Ophthalmology and Visual Sciences, The University of Michigan Medical School, Ann Arbor, MI, United States
| |
Collapse
|
50
|
Chabanon M, Rangamani P. Solubilization kinetics determines the pulsatory dynamics of lipid vesicles exposed to surfactant. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2018; 1860:2032-2041. [PMID: 29572034 DOI: 10.1016/j.bbamem.2018.03.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 03/14/2018] [Accepted: 03/16/2018] [Indexed: 11/25/2022]
Abstract
We establish a biophysical model for the dynamics of lipid vesicles exposed to surfactants. The solubilization of the lipid membrane due to the insertion of surfactant molecules induces a reduction of membrane surface area at almost constant vesicle volume. This results in a rate-dependent increase of membrane tension and leads to the opening of a micron-sized pore. We show that solubilization kinetics due to surfactants can determine the regime of pore dynamics: either the pores open and reseal within a second (short-lived pore), or the pore stays open up to a few minutes (long-lived pore). First, we validate our model with previously published experimental measurements of pore dynamics. Then, we investigate how the solubilization kinetics and membrane properties affect the dynamics of the pore and construct a phase diagram for short and long-lived pores. Finally, we examine the dynamics of sequential pore openings and show that cyclic short-lived pores occur with a period inversely proportional to the solubilization rate. By deriving a theoretical expression for the cycle period, we provide an analytical tool to estimate the solubilization rate of lipid vesicles by surfactants. Our findings shed light on some fundamental biophysical mechanisms that allow simple cell-like structures to sustain their integrity against environmental stresses, and have the potential to aid the design of vesicle-based drug delivery systems. This article is part of a Special Issue entitled: Emergence of Complex Behavior in Biomembranes edited by Marjorie Longo.
Collapse
Affiliation(s)
- Morgan Chabanon
- Department of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla 92093, CA, USA.
| | - Padmini Rangamani
- Department of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla 92093, CA, USA.
| |
Collapse
|