1
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Wei Y, Lv J, Zhu S, Wang S, Su J, Xu C. Enzyme-responsive liposomes for controlled drug release. Drug Discov Today 2024; 29:104014. [PMID: 38705509 DOI: 10.1016/j.drudis.2024.104014] [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: 12/16/2023] [Revised: 04/19/2024] [Accepted: 04/29/2024] [Indexed: 05/07/2024]
Abstract
Compared to other nanovectors, liposomes exhibit unique advantages, such as good biosafety and high drug-loading capacity. However, slow drug release from conventional liposomes makes most payloads unavailable, restricting the therapeutic efficacy. Therefore, in the last ∼20 years, enzyme-responsive liposomes have been extensively investigated, which liberate drugs under the stimulation of enzymes overexpressed at disease sites. In this review, we elaborate on the research progress on enzyme-responsive liposomes. The involved enzymes mainly include phospholipases, particularly phospholipase A2, matrix metalloproteinases, cathepsins, and esterases. These enzymes can cleave ester bonds or specific peptide sequences incorporated in the liposomes for controlled drug release by disrupting the primary structure of liposomes, detaching protective polyethylene glycol shells, or activating liposome-associated prodrugs. Despite decades of efforts, there are still a lack marketed products of enzyme-responsive liposomes. Therefore, more efforts should be made to improve the safety and effectiveness of enzyme-responsive liposomes and address the issues associated with production scale-up.
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Affiliation(s)
- Yan Wei
- Institute of Translational Medicine, Shanghai University, Shanghai 200444, China; Organoid Research Center, Shanghai University, Shanghai 200444, China; Department of Orthopedics, Shanghai Zhongye Hospital, Shanghai 200941, China.
| | - Jiajing Lv
- Institute of Translational Medicine, Shanghai University, Shanghai 200444, China; Organoid Research Center, Shanghai University, Shanghai 200444, China
| | - Shiyu Zhu
- Institute of Translational Medicine, Shanghai University, Shanghai 200444, China; Organoid Research Center, Shanghai University, Shanghai 200444, China
| | - Sicheng Wang
- Department of Orthopedics, Shanghai Zhongye Hospital, Shanghai 200941, China.
| | - Jiacan Su
- Institute of Translational Medicine, Shanghai University, Shanghai 200444, China; Organoid Research Center, Shanghai University, Shanghai 200444, China; Department of Orthopedics, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200092, China.
| | - Can Xu
- Department of Gastroenterology, Changhai Hospital, Shanghai 200433, China.
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2
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Min S, Picou C, Jeong HJ, Bower A, Jeong K, Chung JK. Melittin-Phospholipase A 2 Synergism Is Mediated by Liquid-Liquid Miscibility Phase Transition in Giant Unilamellar Vesicles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:7456-7462. [PMID: 38546877 DOI: 10.1021/acs.langmuir.3c03920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/10/2024]
Abstract
The primary constituents of honeybee venom, melittin and phospholipase A2 (PLA2), display toxin synergism in which the PLA2 activity is significantly enhanced by the presence of melittin. It has been shown previously that this is accomplished by the disruption in lipid packing, which allows PLA2 to become processive on the membrane surface. In this work, we show that melittin is capable of driving miscibility phase transition in giant unilamellar vesicles (GUVs) and that it raises the miscibility transition temperature (Tmisc) in a concentration-dependent manner. The induced phase separation enhances the processivity of PLA2, particularly at its boundaries, where a substantial difference in domain thickness creates a membrane discontinuity. The catalytic action of PLA2, in response, induces changes in the membrane, rendering it more conducive to melittin binding. This, in turn, facilitates further lipid phase separation and eventual vesicle lysis. Overall, our results show that melittin has powerful membrane-altering capabilities that activate PLA2 in various membrane contexts. More broadly, they exemplify how this biochemical system actively modulates and capitalizes on the spatial distribution of membrane lipids to efficiently achieve its objectives.
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Affiliation(s)
- Sein Min
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523 United States
| | - Cyrus Picou
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523 United States
| | - Hye Jin Jeong
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523 United States
| | - Adam Bower
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523 United States
| | - Keunhong Jeong
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523 United States
| | - Jean K Chung
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523 United States
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3
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Nakashima A, Tomono S, Yamazaki T, Inui M, Morita N, Ichimonji I, Takagi H, Nagaoka F, Matsumoto M, Ito Y, Yanagishita T, Miyake K, Watanabe D, Akashi-Takamura S. Phospholipase A2 from bee venom increases poly(I:C)-induced activation in human keratinocytes. Int Immunol 2021; 32:371-383. [PMID: 31957789 DOI: 10.1093/intimm/dxaa005] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Accepted: 01/15/2020] [Indexed: 12/11/2022] Open
Abstract
Bee venom (BV) induces skin inflammation, characterized by erythema, blisters, edemas, pain and itching. Although BV has been found to have an inhibitory effect on toll-like receptors (TLRs), we here show that BV enhances keratinocyte responses to polyinosinic-polycytidylic acid [poly(I:C)], a ligand for TLR3. Our results revealed that the enhanced TLR activity was primarily induced by secretory phospholipase A2 (sPLA2), a component of BV (BV-sPLA2). PLA2 mediates the hydrolysis of membrane phospholipids into lysophospholipids and free fatty acids. We demonstrated that BV-sPLA2 increased the intracellular uptake of poly(I:C), phosphorylation of the nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinases (MAPKs), and poly(I:C)-mediated interleukin 8 production in human keratinocytes. We further showed that the enzymatic activity of BV-sPLA2 was essential for the increased uptake of poly(I:C). These findings suggest that BV-sPLA2 may induce a modification of the cell membrane structure, leading to enhanced poly(I:C) uptake in keratinocytes. BV-sPLA2 might be able to promote wound healing by enhancing TLR3 responses.
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Affiliation(s)
- Akina Nakashima
- Department of Microbiology and Immunology, Aichi Medical University School of Medicine, Nagakute, Aichi, Japan.,Department of Dermatology, Aichi Medical University School of Medicine, Nagakute, Aichi, Japan
| | - Susumu Tomono
- Department of Microbiology and Immunology, Aichi Medical University School of Medicine, Nagakute, Aichi, Japan
| | - Tatsuya Yamazaki
- Department of Microbiology and Immunology, Aichi Medical University School of Medicine, Nagakute, Aichi, Japan
| | - Masanori Inui
- Department of Microbiology and Immunology, Aichi Medical University School of Medicine, Nagakute, Aichi, Japan
| | - Naoko Morita
- Department of Microbiology and Immunology, Aichi Medical University School of Medicine, Nagakute, Aichi, Japan
| | - Isao Ichimonji
- Department of Microbiology and Immunology, Aichi Medical University School of Medicine, Nagakute, Aichi, Japan
| | - Hidekazu Takagi
- Department of Microbiology and Immunology, Aichi Medical University School of Medicine, Nagakute, Aichi, Japan
| | - Fumiaki Nagaoka
- Department of Microbiology and Immunology, Aichi Medical University School of Medicine, Nagakute, Aichi, Japan
| | - Misako Matsumoto
- Department of Vaccine Immunology, Hokkaido University Graduate School of Medicine, Kita-ku, Sapporo, Japan.,Nebuta Research Institute for Life Sciences, Aomori University, Kohbata, Aomori, Japan
| | - Yasuhiko Ito
- Department of Nephrology and Rheumatology, Aichi Medical University School of Medicine, Nagakute, Aichi, Japan
| | - Takeshi Yanagishita
- Department of Dermatology, Aichi Medical University School of Medicine, Nagakute, Aichi, Japan
| | - Kensuke Miyake
- Division of Innate Immunity, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Daisuke Watanabe
- Department of Dermatology, Aichi Medical University School of Medicine, Nagakute, Aichi, Japan
| | - Sachiko Akashi-Takamura
- Department of Microbiology and Immunology, Aichi Medical University School of Medicine, Nagakute, Aichi, Japan
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4
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Simonsen AC, Boye TL, Nylandsted J. Annexins Bend Wound Edges during Plasma Membrane Repair. Curr Med Chem 2020; 27:3600-3610. [DOI: 10.2174/0929867326666190121121143] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Revised: 11/23/2018] [Accepted: 12/04/2018] [Indexed: 02/06/2023]
Abstract
The plasma membrane of eukaryotic cells defines the boundary to the extracellular environment
and, thus provides essential protection from the surroundings. Consequently, disruptions to
the cell membrane triggered by excessive mechanical or biochemical stresses pose fatal threats to
cells, which they need to cope with to survive. Eukaryotic cells cope with these threats by activating
their plasma membrane repair system, which is shared by other cellular functions, and includes
mechanisms to remove damaged membrane by internalization (endocytosis), shedding, reorganization
of cytoskeleton and membrane fusion events to reseal the membrane. Members of the
annexin protein family, which are characterized by their Ca2+-dependent binding to anionic phospholipids,
are important regulators of plasma membrane repair. Recent studies based on cellular and
biophysical membrane models show that they have more distinct functions in the repair response
than previously assumed by regulating membrane curvature and excision of damaged membrane. In
cells, plasma membrane injury and flux of Ca2+ ions into the cytoplasm trigger recruitment of annexins
including annexin A4 and A6 to the membrane wound edges. Here, they induce curvature and
constriction force, which help pull the wound edges together for eventual fusion. Cancer cells are
dependent on efficient plasma membrane repair to counteract frequent stress-induced membrane
injuries, which opens novel avenues to target cancer cells through their membrane repair system.
Here, we discuss mechanisms of single cell wound healing implicating annexin proteins and membrane
curvature.
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Affiliation(s)
- Adam Cohen Simonsen
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, DK- 5230 Odense M, Denmark
| | - Theresa Louise Boye
- Membrane Integrity Group, Unit for Cell Death and Metabolism, Center for Autophagy, Recycling and Disease, Danish Cancer Society Research Center, Strandboulevarden 49, DK- 2100 Copenhagen, Denmark
| | - Jesper Nylandsted
- Membrane Integrity Group, Unit for Cell Death and Metabolism, Center for Autophagy, Recycling and Disease, Danish Cancer Society Research Center, Strandboulevarden 49, DK- 2100 Copenhagen, Denmark
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5
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Berg Klenow M, Camillus Jeppesen J, Simonsen AC. Membrane rolling induced by bacterial toxins. SOFT MATTER 2020; 16:1614-1626. [PMID: 31957755 DOI: 10.1039/c9sm01913h] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Membrane curvature effects are important in numerous cellular processes and many membrane interacting proteins induce spontaneous curvature upon membrane binding. Shiga and cholera toxins both belong to the AB5 family of toxins and consist of a toxic A subunit and a membrane-binding pentameric B subunit. Shiga and cholera toxins induce tubular membrane invaginations in cells and GUVs due to curvature effects and the toxins are known from MD simulations to induce curvature. Membrane invaginations have been linked to uptake of the toxins into cells. As a novel model system to experimentally characterize curvature-inducing proteins, we study the morphology induced in planar membrane patches. It was previously shown that annexins induce distinct morphologies in membrane patches including membrane rolling. In this study we show that the B subunits of Shiga and cholera toxins (STxB, CTxB) both induce roll-up of cell-sized membrane patches. Rolling starts from the free membrane edges of the patch and is completed within a few seconds. We characterize the branched roll morphology and find experimental estimates for the spontaneous curvature of the toxins based on the topography of rolls. The estimates are in agreement with previous MD simulations. We quantify the dynamics of rolling as induced by the toxins and demonstrate agreement with a theoretical model of the rolling dynamics. The model solves the equation of motion for a membrane roll and includes viscous drag and adhesion to the support. The results suggest that membrane rolling may be a general phenomenon displayed by many proteins that induce negative curvature in membranes with free edges.
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Affiliation(s)
- Martin Berg Klenow
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, 5230 Odense M, Denmark.
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6
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Dols-Perez A, Fumagalli L, Gomila G. Interdigitation in spin-coated lipid layers in air. Colloids Surf B Biointerfaces 2018; 172:400-406. [PMID: 30195157 DOI: 10.1016/j.colsurfb.2018.08.041] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Revised: 08/14/2018] [Accepted: 08/19/2018] [Indexed: 10/28/2022]
Abstract
In this study, we show that dry saturated phospholipid layers prepared by the spin-coating technique could present thinner regions associated to interdigitated phases under some conditions. The morphological characteristics of lipid layers of saturated phosphocholines, such as dilauroylphosphatidylcholine (DLPC), dimyristoylphosphatidylcholine (DMPC), dipalmitoylphosphatidylcholine (DPPC) and distearoylphosphatidylcholine (DSPC), have been measured by Atomic Force Microscopy and revealed that the presence of interdigitated regions is not induced by the same parameters that induce them in hydrated samples. To achieve these results the effect of the lipid hidrocabonated chain length, the presence of alcohol in the coating solution, the spinning velocity and the presence of cholesterol were tested. We showed that DPPC and DSPC bilayers, on the one side, can show structures with similar height than interdigitated regions observed in hydrated samples, while, on the other side, DLPC and DMPC tend to show no evidence of interdigitation. Results indicate that the presence of interdigitated areas is due to the presence of lateral tensions and, hence, that they can be eliminated by releasing these tensions by, for instance, the addition of cholesterol. These results demonstrate that interdigitation in lipid layers is a rather general phenomena and can be observed in lipid bilayers in dry conditions.
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Affiliation(s)
- Aurora Dols-Perez
- Department of Bionanoscience, Kavli Institute of Nanoscience, Delft University of Technology, Van der Maasweg 9, 2629 HZ, Delft, Netherlands.
| | - Laura Fumagalli
- School of Physics and Astronomy, University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom
| | - Gabriel Gomila
- Institut de Bioenginyeria de Catalunya (IBEC), C/ Baldiri i Reixac 15-21, 08028, Barcelona, Spain; Departament d'Enginyeria Electrònica i Biomèdica, Universitat de Barcelona, C/ Martí i Franquès 1, 08028, Barcelona, Spain
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7
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Nyström L, Malmsten M. Membrane interactions and cell selectivity of amphiphilic anticancer peptides. Curr Opin Colloid Interface Sci 2018. [DOI: 10.1016/j.cocis.2018.06.009] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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8
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Boye TL, Jeppesen JC, Maeda K, Pezeshkian W, Solovyeva V, Nylandsted J, Simonsen AC. Annexins induce curvature on free-edge membranes displaying distinct morphologies. Sci Rep 2018; 8:10309. [PMID: 29985397 PMCID: PMC6037701 DOI: 10.1038/s41598-018-28481-z] [Citation(s) in RCA: 69] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Accepted: 06/19/2018] [Indexed: 12/31/2022] Open
Abstract
Annexins are a family of proteins characterized by their ability to bind anionic membranes in response to Ca2+-activation. They are involved in a multitude of cellular functions including vesiculation and membrane repair. Here, we investigate the effect of nine annexins (ANXA1-ANXA7, ANXA11, ANXA13) on negatively charged double supported membrane patches with free edges. We find that annexin members can be classified according to the membrane morphology they induce and matching a dendrogam of the annexin family based on full amino acid sequences. ANXA1 and ANXA2 induce membrane folding and blebbing initiated from membrane structural defects inside patches while ANXA6 induces membrane folding originating both from defects and from the membrane edges. ANXA4 and ANXA5 induce cooperative roll-up of the membrane starting from free edges, producing large rolls. In contrast, ANXA3 and ANXA13 roll the membrane in a fragmented manner producing multiple thin rolls. In addition to rolling, ANXA7 and ANXA11 are characterized by their ability to form fluid lenses localized between the membrane leaflets. A shared feature necessary for generating these morphologies is the ability to induce membrane curvature on free edged anionic membranes. Consequently, induction of membrane curvature may be a significant property of the annexin protein family that is important for their function.
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Affiliation(s)
- Theresa Louise Boye
- Membrane Integrity Group, Unit for Cell Death and Metabolism, Danish Cancer Society Research Center, Strandboulevarden 49, DK-2100, Copenhagen, Denmark
| | - Jonas Camillus Jeppesen
- University of Southern Denmark (SDU), Campusvej 55, DK-5230, Odense M, Denmark.,Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Odense, Denmark
| | - Kenji Maeda
- Membrane Integrity Group, Unit for Cell Death and Metabolism, Danish Cancer Society Research Center, Strandboulevarden 49, DK-2100, Copenhagen, Denmark
| | - Weria Pezeshkian
- University of Southern Denmark (SDU), Campusvej 55, DK-5230, Odense M, Denmark.,Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Odense, Denmark
| | - Vita Solovyeva
- University of Southern Denmark (SDU), Campusvej 55, DK-5230, Odense M, Denmark.,Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | - Jesper Nylandsted
- Membrane Integrity Group, Unit for Cell Death and Metabolism, Danish Cancer Society Research Center, Strandboulevarden 49, DK-2100, Copenhagen, Denmark.,Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, DK-2200, Copenhagen N, Denmark
| | - Adam Cohen Simonsen
- University of Southern Denmark (SDU), Campusvej 55, DK-5230, Odense M, Denmark. .,Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Odense, Denmark.
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9
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Abstract
Lauryl gallate (LG) is an antioxidant agent. However, it exhibits poor solubility in water. Its interactions with the membrane result in structure evolution thus affecting the membrane functionality. In this paper the Brewster angle microscope coupled with the Langmuir trough was applied to determine the morphology, phase behaviour, thickness and miscibility of ternary Langmuir monolayers with equal mole fractions of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC); 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) and an increasing mole fraction of LG. The results were discussed as regards analogous systems where cholesterol (Chol) was the third component. Moreover, the phosphatidylcholine–lauryl gallate (PC–LG) interactions were monitored by the attenuated total reflectance Fourier transform infrared spectroscopy and time-of-flight secondary ion mass spectrometry. Besides lipid composition, the addition of LG was found to be a significant factor to modulate the model membrane properties. The LG molecules adjust themselves to the PC monolayer structure. The hydrophobic fragment is dipped into the membrane interior while the hydroxyl groups of phenolic gallate moiety associate with the polar groups of PC mainly through hydrogen bonding inducing the compacting effect. LG is found to be deeply submerged within DOPC, closer to the double bonds, and its insertion practically does not affect the DPPC/DOPC membrane fluidity. This is crucial for getting more profound insight into the role of LG in stabilizing the non-raft domains, mostly exposed to oxidation in which LG can co-localize and serve its antioxidant function.
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10
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Xu J, Sun S, Wang Z, Peng S, Hu S, Zhang L. pH-Induced evolution of surface patterns in micelles assembled from dirhamnolipids: dissipative particle dynamics simulation. Phys Chem Chem Phys 2018; 20:9460-9470. [DOI: 10.1039/c8cp00751a] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Dissipative particle dynamics (DPD) simulation is used to study the effect of pH on the morphological transition in micelles assembled from dirhamnolipids (diRLs), and analyze the pH-driven mechanism and influence factors of micellar surface patterns.
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Affiliation(s)
- Jianchang Xu
- School of Chemistry and Chemical Engineering
- South China University of Technology
- Guangzhou 510640
- China
| | - Shuangqing Sun
- College of Science
- China University of Petroleum (East China)
- Qingdao 266580
- China
| | - Zhikun Wang
- College of Science
- China University of Petroleum (East China)
- Qingdao 266580
- China
| | - Shiyuan Peng
- School of Chemistry and Chemical Engineering
- South China University of Technology
- Guangzhou 510640
- China
| | - Songqing Hu
- College of Science
- China University of Petroleum (East China)
- Qingdao 266580
- China
| | - Lijuan Zhang
- School of Chemistry and Chemical Engineering
- South China University of Technology
- Guangzhou 510640
- China
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11
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Annexin A4 and A6 induce membrane curvature and constriction during cell membrane repair. Nat Commun 2017; 8:1623. [PMID: 29158488 PMCID: PMC5696365 DOI: 10.1038/s41467-017-01743-6] [Citation(s) in RCA: 109] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Accepted: 10/12/2017] [Indexed: 11/12/2022] Open
Abstract
Efficient cell membrane repair mechanisms are essential for maintaining membrane integrity and thus for cell life. Here we show that the Ca2+- and phospholipid-binding proteins annexin A4 and A6 are involved in plasma membrane repair and needed for rapid closure of micron-size holes. We demonstrate that annexin A4 binds to artificial membranes and generates curvature force initiated from free edges, whereas annexin A6 induces constriction force. In cells, plasma membrane injury and Ca2+ influx recruit annexin A4 to the vicinity of membrane wound edges where its homo-trimerization leads to membrane curvature near the edges. We propose that curvature force is utilized together with annexin A6-mediated constriction force to pull the wound edges together for eventual fusion. We show that annexin A4 can counteract various plasma membrane disruptions including holes of several micrometers indicating that induction of curvature force around wound edges is an early key event in cell membrane repair. The role of annexins in cell membrane repair is largely undefined. Here the authors use a model lipid bilayer to show that annexin A4 induces curvature at the membrane free edge and annexin A6 induces constriction force, and find that both annexins are recruited to wound edges in cells and are required for repair.
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12
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Østrem RG, Parhamifar L, Pourhassan H, Clergeaud G, Nielsen OL, Kjær A, Hansen AE, Andresen TL. Secretory phospholipase A 2 responsive liposomes exhibit a potent anti-neoplastic effect in vitro, but induce unforeseen severe toxicity in vivo. J Control Release 2017; 262:212-221. [PMID: 28754610 DOI: 10.1016/j.jconrel.2017.07.031] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Revised: 06/30/2017] [Accepted: 07/24/2017] [Indexed: 01/22/2023]
Abstract
The clinical use of liposomal drug delivery vehicles is often hindered by insufficient drug release. Here we present the rational design of liposomes optimized for secretory phospholipase A2 (sPLA2) triggered drug release, and test their utility in vitro and in vivo. We hypothesized that by adjusting the level of cholesterol in anionic, unsaturated liposomes we could tune the enzyme specificity based on membrane fluidity, thus obtaining liposomes with an improved therapeutic outcome and reduced side effects. Cholesterol is generally important as a component in the membranes of liposome drug delivery systems due to its stabilizing effects in vivo. The incorporation of cholesterol in sPLA2 sensitive liposomes has not previously been possible due to reduced sPLA2 activity. However, in the present work we solved this challenge by optimizing membrane fluidity. In vitro release studies revealed enzyme specific drug release. Treatment of two different cancer cell lines with liposomal oxaliplatin revealed efficient growth inhibition compared to that of clinically used stealth liposomes. The in vivo therapeutic effect was evaluated in nude NMRI mice using the sPLA2 secreting mammary carcinoma cell line MT-3. Three days after first treatment all mice having received the novel sPLA2 sensitive liposome formulation were euthanized due to severe systemic toxicity. Thus the present study demonstrates that great caution should be implemented when utilizing sPLA2 sensitive liposomes and that the real utility can only be disclosed in vivo. The present studies have clinical implications, as sPLA2 sensitive formulations are currently undergoing clinical trials (LiPlaCis®).
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Affiliation(s)
- Ragnhild Garborg Østrem
- Technical University of Denmark, Department of Micro- and Nanotechnology, Center for Nanomedicine and Theranostics, Produktionstorvet, 2800 Kgs. Lyngby, Denmark
| | - Ladan Parhamifar
- Technical University of Denmark, Department of Micro- and Nanotechnology, Center for Nanomedicine and Theranostics, Produktionstorvet, 2800 Kgs. Lyngby, Denmark
| | - Houman Pourhassan
- Technical University of Denmark, Department of Micro- and Nanotechnology, Center for Nanomedicine and Theranostics, Produktionstorvet, 2800 Kgs. Lyngby, Denmark
| | - Gael Clergeaud
- Technical University of Denmark, Department of Micro- and Nanotechnology, Center for Nanomedicine and Theranostics, Produktionstorvet, 2800 Kgs. Lyngby, Denmark
| | - Ole Lerberg Nielsen
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Ridebanevej 3, 1870 Frederiksberg C, Denmark
| | - Andreas Kjær
- Cluster for Molecular Imaging, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen N, Denmark
| | - Anders Elias Hansen
- Technical University of Denmark, Department of Micro- and Nanotechnology, Center for Nanomedicine and Theranostics, Produktionstorvet, 2800 Kgs. Lyngby, Denmark; Cluster for Molecular Imaging, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen N, Denmark
| | - Thomas Lars Andresen
- Technical University of Denmark, Department of Micro- and Nanotechnology, Center for Nanomedicine and Theranostics, Produktionstorvet, 2800 Kgs. Lyngby, Denmark.
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13
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Faizullin DA, Dzyurkevich MS, Valiullina YA, Islamov DR, Kataeva ON, Zuev YF, Plemenkov VV, Stoikov II. Novel type of isoprenoid membrane anchors: an investigation of binding properties with dipalmitoylphosphatidylcholine vesicles. J PHYS ORG CHEM 2017. [DOI: 10.1002/poc.3618] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Dzhigangir A. Faizullin
- Kazan Institute of Biochemistry and Biophysics; Russian Academy of Sciences; Kazan Russia
- Alexander Butlerov Institute of Chemistry; Kazan Federal University; Kazan Russia
| | | | - Yuliya A. Valiullina
- Kazan Institute of Biochemistry and Biophysics; Russian Academy of Sciences; Kazan Russia
| | - Daut R. Islamov
- Alexander Butlerov Institute of Chemistry; Kazan Federal University; Kazan Russia
| | - Olga N. Kataeva
- A.E. Arbuzov Institute of Organic and Physical Chemistry; Russian Academy of Sciences; Kazan Russia
| | - Yuriy F. Zuev
- Kazan Institute of Biochemistry and Biophysics; Russian Academy of Sciences; Kazan Russia
- Alexander Butlerov Institute of Chemistry; Kazan Federal University; Kazan Russia
| | - Vitaliy V. Plemenkov
- Institute of Biochemistry; Immanuel Kant Baltic Federal University; Kaliningrad Russia
| | - Ivan I. Stoikov
- Alexander Butlerov Institute of Chemistry; Kazan Federal University; Kazan Russia
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14
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Brewer J, Thoke HS, Stock RP, Bagatolli LA. Enzymatic studies on planar supported membranes using a widefield fluorescence LAURDAN Generalized Polarization imaging approach. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2017; 1859:888-895. [DOI: 10.1016/j.bbamem.2017.01.024] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Revised: 01/15/2017] [Accepted: 01/19/2017] [Indexed: 12/01/2022]
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15
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Suladze S, Cinar S, Sperlich B, Winter R. Pressure Modulation of the Enzymatic Activity of Phospholipase A2, A Putative Membrane-Associated Pressure Sensor. J Am Chem Soc 2015; 137:12588-96. [DOI: 10.1021/jacs.5b07009] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Saba Suladze
- Department of Chemistry and
Chemical Biology, Biophysical Chemistry, TU Dortmund University, Otto-Hahn-Str. 6, D-44221 Dortmund, Germany
| | - Suleyman Cinar
- Department of Chemistry and
Chemical Biology, Biophysical Chemistry, TU Dortmund University, Otto-Hahn-Str. 6, D-44221 Dortmund, Germany
| | - Benjamin Sperlich
- Department of Chemistry and
Chemical Biology, Biophysical Chemistry, TU Dortmund University, Otto-Hahn-Str. 6, D-44221 Dortmund, Germany
| | - Roland Winter
- Department of Chemistry and
Chemical Biology, Biophysical Chemistry, TU Dortmund University, Otto-Hahn-Str. 6, D-44221 Dortmund, Germany
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16
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Yokota K, Ogino T. Phase separation in lipid bilayer membranes induced by intermixing at a boundary of two phases with different components. Chem Phys Lipids 2015; 191:147-52. [PMID: 26363303 DOI: 10.1016/j.chemphyslip.2015.09.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Revised: 09/01/2015] [Accepted: 09/02/2015] [Indexed: 11/29/2022]
Abstract
We have demonstrated that dynamic phase separation is induced by coalescence of two self-spreading supported lipid bilayers (SLBs) with different components. Coalescence between a phosphocholine/sphingolipid SLB and a phosphocholine/cholesterol one forms raft-like liquid ordered (Lo) domains, which can be observed by fluorescence microscopy at the boundary of two phases. This phase separation process indicates that lipid molecules, such as sphingolipid and cholesterol, are intermixed. When saturated phospholipid is used instead of sphingolipid, small Lo domains are formed. Cholesterol is harder to incorporate with domains of saturated phospholipid than that of sphingolipid. This technique is very useful for observation of lipid-lipid interactions.
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Affiliation(s)
- Keiji Yokota
- Graduate School of Engineering, Yokohama National University, 79-5, Tokiwadai, Yokohama 240-8501, Japan
| | - Toshio Ogino
- Graduate School of Engineering, Yokohama National University, 79-5, Tokiwadai, Yokohama 240-8501, Japan; CREST, JST, Japan.
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17
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Hansen AH, Mouritsen OG, Arouri A. Enzymatic action of phospholipase A2 on liposomal drug delivery systems. Int J Pharm 2015; 491:49-57. [DOI: 10.1016/j.ijpharm.2015.06.005] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Revised: 06/03/2015] [Accepted: 06/04/2015] [Indexed: 12/17/2022]
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18
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Abstract
All biological membranes consist of a complex composite of macromolecules and macromolecular assemblies, of which the fluid lipid-bilayer component is a core element with regard to cell encapsulation and barrier properties. The fluid lipid bilayer also supports the functional machinery of receptors, channels and pumps that are associated with the membrane. This bilayer is stabilized by weak physical and colloidal forces, and its nature is that of a self-assembled system of amphiphiles in water. Being only approximately 5 nm in thickness and still encapsulating a cell that is three orders of magnitude larger in diameter, the lipid bilayer as a material has very unusual physical properties, both in terms of structure and dynamics. Although the lipid bilayer is a fluid, it has a distinct and structured trans-bilayer profile, and in the plane of the bilayer the various molecular components, viz different lipid species and membrane proteins, have the capacity to organize laterally in terms of differentiated domains on different length and time scales. These elements of small-scale structure and order are crucial for the functioning of the membrane. It has turned out to be difficult to quantitatively study the small-scale structure of biological membranes. A major part of the insight into membrane micro- and nano-domains and the concepts used to describe them have hence come from studies of simple lipid bilayers as models of membranes, by use of a wide range of theoretical, experimental and simulational approaches. Many questions remain to be answered as to which extent the result from model studies can carry over to real biological membranes.
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Liland NS, Simonsen AC, Duelund L, Torstensen BE, Berntssen MHG, Mouritsen OG. Polyaromatic hydrocarbons do not disturb liquid-liquid phase coexistence, but increase the fluidity of model membranes. Chem Phys Lipids 2014; 184:18-24. [PMID: 25181555 DOI: 10.1016/j.chemphyslip.2014.08.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Revised: 08/26/2014] [Accepted: 08/28/2014] [Indexed: 12/21/2022]
Abstract
Polyaromatic hydrocarbons (PAHs) is a group of compounds, many of which are toxic, formed by incomplete combustion or thermal processing of organic material. They are highly lipophilic and thus present in some seed oils used for human consumption as well as being increasingly common in aquaculture diets due to inclusion of vegetable oils. Cytotoxic effects of PAHs have been thought to be partly due to a membrane perturbing effect of these compounds. A series of studies were here performed to examine the effects of three different PAHs (naphthalene, phenanthrene and benzo[a]pyrene) with different molecular sizes (two, three and five rings, respectively) and fat solubility (Kow 3.29, 4.53 and 6.04, respectively) on membrane models. The effects of PAHs on liquid-liquid phase coexistence in solid-supported lipid bilayers (dioleoylphosphocholine:dipalmitoylphosphatidylcholine:cholesterol) were assessed using fluorescence microscopy. Benzo[a]pyrene had a slight affinity for the liquid-ordered phase, but there were no effects of adding any of the other PAHs on the number or size of the liquid domains (liquid-ordered and liquid-disordered). Benzo[a]pyrene and phenanthrene, but not naphthalene, lowered the transition temperature (Tm) and the enthalpy (ΔH) characterising the transition from the solid to the liquid-crystalline phase in DPPC vesicles. The membrane effects of the PAH molecules are likely related to size, with bigger and more fat-soluble molecules having a fluidising effect when embedded in the membrane, possibly causing some of the observed toxic effects in fish exposed to these contaminants.
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Affiliation(s)
- Nina S Liland
- National Institute of Nutrition and Seafood Research (NIFES), P.O. Box 2029, Strandgaten 229, Bergen 5817, Norway.
| | - Adam C Simonsen
- MEMPHYS, University of Southern Denmark, Campusvej 55, Odense-M DK-5230, Denmark.
| | - Lars Duelund
- MEMPHYS, University of Southern Denmark, Campusvej 55, Odense-M DK-5230, Denmark.
| | - Bente E Torstensen
- National Institute of Nutrition and Seafood Research (NIFES), P.O. Box 2029, Strandgaten 229, Bergen 5817, Norway.
| | - Marc H G Berntssen
- National Institute of Nutrition and Seafood Research (NIFES), P.O. Box 2029, Strandgaten 229, Bergen 5817, Norway.
| | - Ole G Mouritsen
- MEMPHYS, University of Southern Denmark, Campusvej 55, Odense-M DK-5230, Denmark.
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20
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Beaulieu E, Ioffe J, Watson SN, Hermann PM, Wildering WC. Oxidative-stress induced increase in circulating fatty acids does not contribute to phospholipase A2-dependent appetitive long-term memory failure in the pond snail Lymnaea stagnalis. BMC Neurosci 2014; 15:56. [PMID: 24886155 PMCID: PMC4013061 DOI: 10.1186/1471-2202-15-56] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2013] [Accepted: 04/23/2014] [Indexed: 11/23/2022] Open
Abstract
Background Reactive oxygen species (ROS) are essential for normal physiological functioning of the brain. However, uncompensated increase in ROS levels may results in oxidative stress. Phospholipase A2 (PLA2) is one of the key players activated by elevated ROS levels resulting in the hydrolysis of various products from the plasmamembrane such as peroxidized fatty acids. Free fatty acids (FFAs) and fatty acid metabolites are often implicated to the genesis of cognitive impairment. Previously we have shown that age-, and experimentally induced oxidative stress causes PLA2-dependent long-term memory (LTM) failure in an aversive operant conditioning model in Lymnaea stagnalis. In the present study, we investigate the effects of experimentally induced oxidative stress and the role of elevated levels of circulating FFAs on LTM function using a non-aversive appetitive classical conditioning paradigm. Results We show that intracoelomic injection of exogenous PLA2 or pro-oxidant induced PLA2 activation negatively affects LTM performance in our learning paradigm. In addition, we show that experimental induction of oxidative stress causes significant temporal changes in circulating FFA levels. Importantly, the time of training coincides with the peak of this change in lipid metabolism. However, intracoelomic injection with exogenous arachidonic acid, one of the main FFAs released by PLA2, does not affect LTM function. Moreover, sequestrating circulating FFAs with the aid of bovine serum albumin does not rescue pro-oxidant induced appetitive LTM failure. Conclusions Our data substantiates previous evidence linking lipid peroxidation and PLA2 activation to age- and oxidative stress-related cognitive impairment, neuronal dysfunction and disease. In addition however, our data indicate that lipid peroxidation induced increased levels of circulating (per)oxidized FFAs are not a factor in oxidative stress induced LTM impairment.
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Affiliation(s)
| | | | | | | | - Willem C Wildering
- Department of Biological Sciences, Faculty of Science, University of Calgary, Calgary, Alberta T2N 1N4, Canada.
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21
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Rocha S, De Keersmaecker H, Hutchison JA, Vanhoorelbeke K, Martens JA, Hofkens J, Uji-i H. Membrane remodeling processes induced by phospholipase action. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:4743-4751. [PMID: 24694028 DOI: 10.1021/la500121f] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Important cellular events such as division require drastic changes in the shape of the membrane. These remodeling processes can be triggered by the binding of specific proteins or by changes in membrane composition and are linked to phospholipid metabolism for which dedicated enzymes, named phospholipases, are responsible. Here wide-field fluorescence microscopy is used to visualize shape changes induced by the action of phospholipase A1 on dye-labeled supported membranes of POPC (1-palmitoyl-2-oleoly-sn-glycero-3-phosphocholine). Time-lapse imaging demonstrates that layers either shrink and disappear or fold and collapse into vesicles. These vesicles can undergo further transformations such as budding, tubulation, and pearling within 5 min of formation. Using dye-labeled phospholipases, we can monitor the presence of the enzyme at specific positions on the membrane as the shape transformations occur. Furthermore, incorporating the products of hydrolysis into POPC membranes is shown to induce transformations similar to those observed for enzyme action. The results suggest that phospholipase-mediated hydrolysis plays an important role in membrane transformations by altering the membrane composition, and a model is proposed for membrane curvature based on the presence and shape of hydrolysis products.
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Affiliation(s)
- Susana Rocha
- Molecular Imaging and Photonics, Faculty of Science and ‡Centre for Surface Chemistry and Catalysis, Faculty of Bioscience Engineering, KU Leuven , Belgium
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22
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Dols-Perez A, Fumagalli L, Gomila G. Structural and nanomechanical effects of cholesterol in binary and ternary spin-coated single lipid bilayers in dry conditions. Colloids Surf B Biointerfaces 2014; 116:295-302. [DOI: 10.1016/j.colsurfb.2013.12.049] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2013] [Revised: 11/26/2013] [Accepted: 12/21/2013] [Indexed: 12/24/2022]
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23
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Khmelinskaia A, Ibarguren M, de Almeida RFM, López DJ, Paixão VA, Ahyayauch H, Goñi FM, Escribá PV. Changes in membrane organization upon spontaneous insertion of 2-hydroxylated unsaturated fatty acids in the lipid bilayer. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:2117-2128. [PMID: 24490728 DOI: 10.1021/la403977f] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Recent research regarding 2-hydroxylated fatty acids (2OHFAs) showed clear evidence of their benefits in the treatment of cancer, inflammation, and neurodegenerative disorders such as Alzheimer's disease. Monolayer compressibility isotherms and isothermal titration calorimetry of 2OHFA (C18-C22) in phosphatidylcholine/phosphatidylethanolamine/sphingomyelin/cholesterol (1:1:1:1 mole ratio), a mixture that mimics the composition of mammalian plasma membrane, were performed to assess the membrane binding capacity of 2OHFAs and their natural, nonhydroxylated counterparts. The results show that 2OHFAs are surface-active substances that bind membranes through exothermic, spontaneous processes. The main effects of 2OHFAs are a decrease in lipid order, with a looser packing of the acyl chains, and a decreased dipole potential, regardless of the 2OHFAs' relative affinity for the lipid bilayer. The strongest effects are usually observed for 2-hydroxyarachidonic (C20:4) acid, and the weakest one, for 2-hydroxydocosahexaenoic acid (C22:6). In addition, 2OHFAs cause increased hydration, except in gel-phase membranes, which can be explained by the 2OHFA preference for membrane defects. Concerning the membrane dipole potential, the magnitude of the reduction induced by 2OHFAs was particularly marked in the liquid-ordered (lo) phase (cholesterol/sphingomyelin-rich) membranes, those where order reduction was the smallest, suggesting a disruption of cholesterol-sphingolipid interactions that are responsible for the large dipole potential in those membranes. Moreover, 2OHFA effects were larger than for both lo and ld phases separately in model membranes with liquid disordered (ld)/lo coexistence when both phases were present in significant amounts, possibly because of the facilitating effect of ld/lo domain interfaces. The specific and marked changes induced by 2OHFAs in several membrane properties suggest that the initial interaction with the membrane and subsequent reorganization might constitute an important step in their mechanisms of action.
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Affiliation(s)
- Alena Khmelinskaia
- Centro de Quimica e Bioquimica, DQB, Faculdade de Ciências da Universidade de Lisboa , Campo Grande, Ed. C8, 1749-016 Lisboa Portugal
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24
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Lin CY, Chao L. Tunable nucleation time of functional sphingomyelinase--lipid features studied by membrane array statistic tool. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:13008-17. [PMID: 24059643 DOI: 10.1021/la401826b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Aggregation or assembly of lipids and proteins could significantly change the proteins' function. A peripheral membrane enzyme, sphingomyelinase (SMase), has been reported to be able to assemble to a functional feature with its lipid substrate, sphingomyelin (SM), and its lipid product, ceramide (Cer). SMase seems to processes its substrate more effectively in this feature. Here, we report that the functional feature has a tunable formation time. The peculiar behavior is that the feature formation has a time lag depending on the membrane composition. We hypothesized that the time lag is due to the significant nucleation energy barrier when the feature phase forms in its metastable parent phase in the 2-D lipid membrane. To study the stochastic nucleation of the feature, we built a corralled lipid membrane platform with numerous isolated membrane systems in parallel to capture the nucleation statistics. Using the high-throughput approach and the appropriate experimental design to circumvent the interplay of the complicated phase segregation in membranes induced by SMase, we found that the nucleation rate of the feature can be tuned by the supersaturation of the enzyme, the lipid substrate, and the lipid product, in the fluid phase of the membrane. The correlation between the supersaturation and the nucleation rate can be well described by the classical nucleation theory equation, suggesting that the feature formation follows the nucleation process with a certain component ratio specified in the equation. The certain relative component ratio suggests that the feature may have certain organization instead of being random aggregation. In addition, our finding suggests that nucleation could serve as a time lag control mechanism in this enzymatic system, and ways to reduce nucleation energy barrier could be used to shorten the aggregation time lag and vice versa.
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Affiliation(s)
- Charng-Yu Lin
- Department of Chemical Engineering, National Taiwan University , Taipei 106, Taiwan
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25
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Arouri A, Hansen AH, Rasmussen TE, Mouritsen OG. Lipases, liposomes and lipid-prodrugs. Curr Opin Colloid Interface Sci 2013. [DOI: 10.1016/j.cocis.2013.06.001] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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26
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Wu H, Yu L, Tong Y, Ge A, Yau S, Osawa M, Ye S. Enzyme-catalyzed hydrolysis of the supported phospholipid bilayers studied by atomic force microscopy. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2013; 1828:642-51. [DOI: 10.1016/j.bbamem.2012.09.010] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2012] [Revised: 09/06/2012] [Accepted: 09/07/2012] [Indexed: 01/17/2023]
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27
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Gözen I, Jesorka A. Instrumental Methods to Characterize Molecular Phospholipid Films on Solid Supports. Anal Chem 2012; 84:822-38. [DOI: 10.1021/ac203126f] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Irep Gözen
- Department of Chemical and Biological
Engineering, Chalmers University of Technology, Kemivägen 10, 41296 Göteborg, Sweden
| | - Aldo Jesorka
- Department of Chemical and Biological
Engineering, Chalmers University of Technology, Kemivägen 10, 41296 Göteborg, Sweden
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28
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Correlation between the ripple phase and stripe domains in membranes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2011; 1808:2849-58. [DOI: 10.1016/j.bbamem.2011.08.023] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2011] [Revised: 08/12/2011] [Accepted: 08/16/2011] [Indexed: 12/19/2022]
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29
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Dols-Perez A, Fumagalli L, Simonsen AC, Gomila G. Ultrathin spin-coated dioleoylphosphatidylcholine lipid layers in dry conditions: a combined atomic force microscopy and nanomechanical study. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:13165-13172. [PMID: 21936555 DOI: 10.1021/la202942j] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Atomic force microscopy (AFM) has been used to study the structural and mechanical properties of low concentrated spin-coated dioleoylphosphatidylcholine (DOPC) layers in dry environment (RH ≈ 0%) at the nanoscale. It is shown that for concentrations in the 0.1-1 mM range the structure of the DOPC spin-coated samples consists of an homogeneous lipid monolayer ∼1.3 nm thick covering the whole substrate on top of which lipid bilayer (or multilayer) micro- and nanometric patches and rims are formed. The thickness of the bilayer structures is found to be ∼4.5 nm (or multiples of this value for multilayer structures), while the lateral dimensions range from micrometers to tens of nanometer depending on the lipid concentration. The force required to break a bilayer (breakthrough force) is found to be ∼0.24 nN. No dependence of the mechanical values on the lateral dimensions of the bilayer structures is evidenced. Remarkably, the thickness and breakthrough force values of the bilayers measured in dry environment are very similar to values reported in the literature for supported DOPC bilayers in pure water.
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Affiliation(s)
- Aurora Dols-Perez
- Nanobioelec group, Institut de Bioenginyeria de Catalunya (IBEC), Baldiri i Reixac 15-21, 08028 Barcelona, Spain.
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30
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Leidy C, Ocampo J, Duelund L, Mouritsen OG, Jørgensen K, Peters GH. Membrane restructuring by phospholipase A2 is regulated by the presence of lipid domains. Biophys J 2011; 101:90-9. [PMID: 21723818 DOI: 10.1016/j.bpj.2011.02.062] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2010] [Revised: 02/22/2011] [Accepted: 02/24/2011] [Indexed: 12/13/2022] Open
Abstract
Secretory phospholipase A(2) (sPLA(2)) catalyzes the hydrolysis of glycerophospholipids. This enzyme is sensitive to membrane structure, and its activity has been shown to increase in the presence of liquid-crystalline/gel (L(α)/L(β)) lipid domains. In this work, we explore whether lipid domains can also direct the activity of the enzyme by inducing hydrolysis of certain lipid components due to preferential activity of the enzyme toward lipid domains susceptible to sPLA(2). Specifically, we show that the presence of L(α)/L(β) and L(α)/P(β') phase coexistence in a 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC)/1,2 distearoyl-sn-glycero-3-phosphocholine (DSPC) system results in the preferential hydrolysis of the shorter-chained lipid component in the mixture, leading to an enrichment in the longer-chained component. The restructuring process is monitored by atomic force microscopy on supported single and double bilayers formed by vesicle fusion. We observe that during preferential hydrolysis of the DMPC-rich L(α) regions, the L(β) and P(β') regions grow and reseal, maintaining membrane integrity. This result indicates that a sharp reorganization of the membrane structure can occur during sPLA(2) hydrolysis without necessarily destroying the membrane. We confirm by high-performance liquid chromatography the preferential hydrolysis of DMPC within the phase coexistence region of the DMPC/DSPC phase diagram, showing that this preferential hydrolysis is accentuated close to the solidus phase boundary. Differential scanning calorimetry results show that this preferential hydrolysis in the presence of lipid domains leads to a membrane system with a higher-temperature melting profile due to enrichment in DSPC. Together, these results show that the presence of lipid domains can induce specificity in the hydrolytic activity of the enzyme, resulting in marked differences in the physical properties of the membrane end-product.
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Affiliation(s)
- Chad Leidy
- Department of Physics, Universidad de los Andes, Bogotá, Colombia.
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31
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Abstract
Ever since it was discovered that biological membranes have a core of a bimolecular sheet of lipid molecules, lipid bilayers have been a model laboratory for investigating physicochemical and functional properties of biological membranes. Experimental and theoretical models help the experimental scientist to plan experiments and interpret data. Theoretical models are the theoretical scientist's preferred toys to make contact between membrane theory and experiments. Most importantly, models serve to shape our intuition about which membrane questions are the more fundamental and relevant ones to pursue. Here we review some membrane models for lipid self-assembly, monolayers, bilayers, liposomes, and lipid-protein interactions and illustrate how such models can help answering questions in modern lipid cell biology.
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Affiliation(s)
- Ole G Mouritsen
- MEMPHYS-Center for Biomembrane Physics, Department of Physics and Chemistry, University of Southern Denmark, DK-5230 Odense M, Denmark.
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32
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Mouritsen OG. Lipids, curvature, and nano-medicine. EUR J LIPID SCI TECH 2011; 113:1174-1187. [PMID: 22164124 PMCID: PMC3229985 DOI: 10.1002/ejlt.201100050] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2011] [Revised: 06/30/2011] [Accepted: 06/30/2011] [Indexed: 12/29/2022]
Abstract
The physical properties of the lamellar lipid-bilayer component of biological membranes are controlled by a host of thermodynamic forces leading to overall tensionless bilayers with a conspicuous lateral pressure profile and build-in curvature-stress instabilities that may be released locally or globally in terms of morphological changes. In particular, the average molecular shape and the propensity of the different lipid and protein species for forming non-lamellar and curved structures are a source of structural transitions and control of biological function. The effects of different lipids, sterols, and proteins on membrane structure are discussed and it is shown how one can take advantage of the curvature-stress modulations brought about by specific molecular agents, such as fatty acids, lysolipids, and other amphiphilic solutes, to construct intelligent drug-delivery systems that function by enzymatic triggering via curvature.Practical applications: The simple concept of lipid molecular shape and how it impacts on the structure of lipid aggregates, in particular the curvature and curvature stress in lipid bilayers and liposomes, can be exploited to construct liposome-based drug-delivery systems, e.g., for use as nano-medicine in cancer therapy. Non-lamellar-forming lysolipids and fatty acids, some of which may be designed to be prodrugs, can be created by phospholipase action in diseased tissues thereby providing for targeted drug release and proliferation of molecular entities with conical shape that break down the permeability barrier of the target cells and may hence enhance efficacy.
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Affiliation(s)
- Ole G Mouritsen
- MEMPHYS - Center for Biomembrane Physics, Department of Physics and Chemistry, University of Southern Denmark Campusvej, Odense M, Denmark
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33
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Lee JCM, Simonyi A, Sun AY, Sun GY. Phospholipases A2 and neural membrane dynamics: implications for Alzheimer's disease. J Neurochem 2011; 116:813-9. [PMID: 21214562 DOI: 10.1111/j.1471-4159.2010.07033.x] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Phospholipases A(2) (PLA(2)s) are essential enzymes in cells. They are not only responsible for maintaining the structural organization of cell membranes, but also play a pivotal role in the regulation of cell functions. Activation of PLA(2) s results in the release of fatty acids and lysophospholipids, products that are lipid mediators and compounds capable of altering membrane microdomains and physical properties. Although not fully understood, recent studies have linked aberrant PLA(2) activity to oxidative signaling pathways involving NADPH oxidase that underlie the pathophysiology of a number of neurodegenerative diseases. In this paper, we review studies describing the involvement of cytosolic PLA(2) in oxidative signaling pathways leading to neuronal impairment and activation of glial cell inflammatory responses. In addition, this review also includes information on the role of cytosolic PLA(2) and exogenous secretory PLA(2) on membrane physical properties, dynamics, and membrane proteins. Unraveling the mechanisms that regulate specific types of PLA(2)s and their effects on membrane dynamics are important prerequisites towards understanding their roles in the pathophysiology of Alzheimer's disease, and in the development of novel therapeutics to retard progression of the disease.
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Affiliation(s)
- James C-M Lee
- Biological Engineering Department, University of Missouri, Columbia, Missouri 65211, USA
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34
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Mouritsen OG. Lipidology and lipidomics––quo vadis? A new era for the physical chemistry of lipids. Phys Chem Chem Phys 2011; 13:19195-205. [DOI: 10.1039/c1cp22484k] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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35
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Steinem C, Janshoff A. Multicomponent membranes on solid substrates: Interfaces for protein binding. Curr Opin Colloid Interface Sci 2010. [DOI: 10.1016/j.cocis.2010.06.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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36
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Bagatolli LA, Ipsen JH, Simonsen AC, Mouritsen OG. An outlook on organization of lipids in membranes: Searching for a realistic connection with the organization of biological membranes. Prog Lipid Res 2010; 49:378-89. [DOI: 10.1016/j.plipres.2010.05.001] [Citation(s) in RCA: 174] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2010] [Revised: 04/30/2010] [Accepted: 05/01/2010] [Indexed: 12/20/2022]
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Fluorescent probe partitioning in giant unilamellar vesicles of ‘lipid raft’ mixtures. Biochem J 2010; 430:415-23. [DOI: 10.1042/bj20100516] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Direct visualization of raft-like lo (liquid-ordered) domains in model systems and cells using microscopic techniques requires fluorescence probes with known partitioning preference for one of the phases present. However, fluorescent probes may display dissimilar partitioning preferences in different lipid sys-tems and can also affect the phase behaviour of the host lipid bilayer. Therefore a detailed understanding of the behaviour of fluorescent probes in defined lipid bilayer systems with known phase behaviour is essential before they can be used for identifying domain phase states. Using giant unilamellar vesicles composed of the ternary lipid mixture DOPC (1,2-dioleoyl-sn-glycero-3-phosphocholine)/DPPC (1,2-dipalmitoyl-sn-glycero-3-phosphocholine)/cholesterol, for which the phase behaviour is known, we examined nine commonly used fluorescent probes using confocal fluorescence microscopy. The partitioning preference of each probe was assigned either on the basis of quantification of the domain area fractions or by using a well-characterized ld (liquid-disordered)-phase marker. Fluorescent probes were examined both individually and using dual or triple labelling approaches. Most of the probes partitioned individually into the ld phase, whereas only NAP (naphtho[2,3-a]pyrene) and NBD-DPPE [1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine-N-(7-nitro-2-1,3-benzoxadiazol-4-yl] preferred the lo phase. We found that Rh-DPPE (Lissamine™ rhodamine B–1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine) increased the miscibility transition temperature, Tmix. Interestingly, the partitioning of DiIC18 (1,1′-dioctadecyl-3,3,3′,3′-tetramethylindocarbocyanine perchlorate) was influenced by Bodipy®-PC [2-(4,4-difluoro-5,7-dimethyl-4-bora-3a,4a-diaza-s-indacene-3-pentanoyl)-1-hexa-decanoyl-sn-glycero-3-phosphocholine]. The specific use of each of the fluorescent probes is determined by its photostability, partitioning preference, ability to detect lipid phase separations and induced change in Tmix. We demonstrate the importance of testing a specific fluorescent probe in a given model membrane system, rather than assuming that it labels a particular lipid phase.
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Ocampo J, Afanador N, Vives MJ, Moreno JC, Leidy C. The antibacterial activity of phospholipase A2 type IIA is regulated by the cooperative lipid chain melting behavior in Staphylococcus aureus. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2010; 1798:1021-8. [DOI: 10.1016/j.bbamem.2009.11.017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2009] [Revised: 10/31/2009] [Accepted: 11/24/2009] [Indexed: 11/29/2022]
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Gudmand M, Rocha S, Hatzakis NS, Peneva K, Müllen K, Stamou D, Uji-I H, Hofkens J, Bjørnholm T, Heimburg T. Influence of lipid heterogeneity and phase behavior on phospholipase A2 action at the single molecule level. Biophys J 2010; 98:1873-82. [PMID: 20441751 PMCID: PMC2862199 DOI: 10.1016/j.bpj.2010.01.035] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2009] [Revised: 01/14/2010] [Accepted: 01/15/2010] [Indexed: 10/19/2022] Open
Abstract
We monitored the action of phospholipase A(2) (PLA(2)) on L- and D-dipalmitoyl-phosphatidylcholine (DPPC) Langmuir monolayers by mounting a Langmuir-trough on a wide-field fluorescence microscope with single molecule sensitivity. This made it possible to directly visualize the activity and diffusion behavior of single PLA(2) molecules in a heterogeneous lipid environment during active hydrolysis. The experiments showed that enzyme molecules adsorbed and interacted almost exclusively with the fluid region of the DPPC monolayers. Domains of gel state L-DPPC were degraded exclusively from the gel-fluid interface where the buildup of negatively charged hydrolysis products, fatty acid salts, led to changes in the mobility of PLA(2). The mobility of individual enzymes on the monolayers was characterized by single particle tracking. Diffusion coefficients of enzymes adsorbed to the fluid interface were between 3.2 microm(2)/s on the L-DPPC and 4.9 microm(2)/s on the D-DPPC monolayers. In regions enriched with hydrolysis products, the diffusion dropped to approximately 0.2 microm(2)/s. In addition, slower normal and anomalous diffusion modes were seen at the L-DPPC gel domain boundaries where hydrolysis took place. The average residence times of the enzyme in the fluid regions of the monolayer and on the product domain were between approximately 30 and 220 ms. At the gel domains it was below the experimental time resolution, i.e., enzymes were simply reflected from the gel domains back into solution.
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Affiliation(s)
- Martin Gudmand
- Membrane Biophysics Group, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
- Nano-Science Center, University of Copenhagen, Copenhagen, Denmark
| | - Susana Rocha
- Laboratory for Photochemistry and Spectroscopy, Department of Chemistry, Catholic University of Leuven, Leuven, Belgium
| | | | - Kalina Peneva
- Max Planck Institut für Polymerforschung, Mainz, Germany
| | - Klaus Müllen
- Max Planck Institut für Polymerforschung, Mainz, Germany
| | - Dimitrios Stamou
- Nano-Science Center, University of Copenhagen, Copenhagen, Denmark
| | - Hiroshi Uji-I
- Laboratory for Photochemistry and Spectroscopy, Department of Chemistry, Catholic University of Leuven, Leuven, Belgium
| | - Johan Hofkens
- Laboratory for Photochemistry and Spectroscopy, Department of Chemistry, Catholic University of Leuven, Leuven, Belgium
| | - Thomas Bjørnholm
- Nano-Science Center, University of Copenhagen, Copenhagen, Denmark
| | - Thomas Heimburg
- Membrane Biophysics Group, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
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Silva LC, Futerman AH, Prieto M. Lipid raft composition modulates sphingomyelinase activity and ceramide-induced membrane physical alterations. Biophys J 2009; 96:3210-22. [PMID: 19383465 DOI: 10.1016/j.bpj.2008.12.3923] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2008] [Revised: 12/09/2008] [Accepted: 12/11/2008] [Indexed: 01/08/2023] Open
Abstract
Lipid rafts and ceramide (Cer)-platforms are membrane domains that play an important role in several biological processes. Cer-platforms are commonly formed in the plasma membrane by the action of sphingomyelinase (SMase) upon hydrolysis of sphingomyelin (SM) within lipid rafts. The interplay among SMase activity, initial membrane properties (i.e., phase behavior and lipid lateral organization) and lipid composition, and the amount of product (Cer) generated, and how it modulates membrane properties were studied using fluorescence methodologies in model membranes. The activity of SMase was evaluated by following the hydrolysis of radioactive SM. It was observed that 1), the enzyme activity and extent of hydrolysis are strongly dependent on membrane physical properties but not on substrate content, and are higher in raft-like mixtures, i.e., mixtures with liquid-disordered/liquid-ordered phase separation; and 2), Cer-induced alterations are also dependent on membrane composition, specifically the cholesterol (Chol) content. In the lowest-Chol range, Cer segregates together with SM into small ( approximately 8.5 nm) Cer/SM-gel domains. With increasing Chol, the ability of Cer to recruit SM and form gel domains strongly decreases. In the high-Chol range, a Chol-enriched/SM-depleted liquid-ordered phase predominates. Together, these data suggest that in biological membranes, Chol in particular and raft domains in general play an important role in modulating SMase activity and regulating membrane physical properties by restraining Cer-induced alterations.
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Affiliation(s)
- Liana C Silva
- Centro de Química-Física Molecular & Institute of Nanoscience and Nanotechnology, Instituto Superior Técnico, Lisbon, Portugal
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Vandoolaeghe P, Rennie AR, Campbell RA, Nylander T. Neutron reflectivity studies of the interaction of cubic-phase nanoparticles with phospholipid bilayers of different coverage. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:4009-4020. [PMID: 19714826 DOI: 10.1021/la802766n] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Liquid-crystalline cubic-phase nanoparticles (CPNPs) (known as Cubosome particles), based on the lipid glycerol monooleate and stabilized by the nonionic block copolymer Pluronic F-127, interact with supported model membranes consisting of dioleoylphosphatidylcholine (DOPC) in a complex and dynamic fashion. Neutron reflectivity measurements on the interaction of CPNPs with bilayers of different coverage have increased our understanding of an interfacial exchange mechanism that is relevant to delivery applications. To access the composition of the adsorption layer, the method of isotopic contrast between the components was exploited by using DOPC with perdeuterated acyl chains, which are distinguishable (high scattering contrast) from the hydrogenous components of the CPNPs. The exchange of material between CPNPs and the bilayer takes place regardless of the initial bilayer coverage. However, this parameter has a strong influence on the physical nature of the layer formed upon interaction. For a bilayer of "high coverage" (80%), extensive exchange takes place between the CPNP components and the bilayer, and at steady state the surface layer comprises 72% glycerol monooleate and 8% DOPC, with no change in the solvent content. An analogous experiment involving pure glycerol monooleate liquid crystals shows that lipid exchange occurs even in the absence of the stabilizing polymer. For bilayers of "low coverage" (55%), the exchange mechanism involves an initial adsorption of material from the CPNPs to fill in the bilayer defects. However, most of the bilayer breaks up and only 15% coverage remains after 30 h. The evolution of a Bragg diffraction peak was monitored in this case to show that the bound nanoparticles occupy >7% surface coverage and have a periodicity in the density of the internal lipid structure that decreases with time. This progression is attributed to the incorporation of d-DOPC molecules within the internal cubic structure of the nanoparticles. The broadening of the diffraction peak with time, together with a final mean position that is closely related to the periodicity of the lamellar phase organization of GMO, shows that the lipid-exchange process results in either a contraction of the unit cell of the cubic-phase nanoparticles or a progression of the lipid arrangement to the lamellar phase.
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Affiliation(s)
- Pauline Vandoolaeghe
- Center for Chemistry and Chemical Engineering, Physical Chemistry 1, Lund University, P.O. Box 124, SE-22100 Lund, Sweden.
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Activation of phospholipase A2 by temporin B: formation of antimicrobial peptide-enzyme amyloid-type cofibrils. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2009; 1788:1064-72. [PMID: 19285031 DOI: 10.1016/j.bbamem.2009.03.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2008] [Revised: 03/03/2009] [Accepted: 03/03/2009] [Indexed: 11/21/2022]
Abstract
Phospholipases A2 have been shown to be activated in a concentration dependent manner by a number of antimicrobial peptides, including melittin, magainin 2, indolicidin, and temporins B and L. Here we used fluorescently labelled bee venom PLA2 (PLA2D) and the saturated phospholipid substrate 1,2-dipalmitoyl-glycero-sn-3-phosphocholine (L-DPPC), exhibiting a lag-burst behaviour upon the initiation of the hydrolytic reaction by PLA2. Increasing concentrations of Cys-temporin B and its fluorescent Texas red derivative (TRC-temB) caused progressive shortening of the lag period. TRC-temB/PLA2D interaction was observed by Förster resonance energy transfer (FRET), with maximum efficiency coinciding with the burst in hydrolysis. Subsequently, supramolecular structures became visible by microscopy, revealing amyloid-like fibrils composed of both the activating peptide and PLA2. Reaction products, palmitic acid and 1-palmitoyl-2-lyso-glycero-sn-3-phosphocholine (lysoPC, both at >8 mol%) were required for FRET when using the non-hydrolysable substrate enantiomer 2,3-dipalmitoyl-glycero-sn-1-phosphocholine (D-DPPC). A novel mechanism of PLA2 activation by co-fibril formation and associated conformational changes is suggested.
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