151
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Abstract
Strategies for gene delivery comprise a diverse range of live and synthetic approaches; DNA delivery for the purposes of immunisation in turn comprises a large part of this research. This review mainly discusses synthetic systems for application in the delivery of plasmid DNA vaccines, outlining polylactide-co-glycolide, liposome, chitosan and complex combination delivery systems. Areas of promise for DNA vaccine candidates include immune modulation of allergic responses and veterinarian application. The potential for realistic consideration of DNA vaccines as an alternative to existing approaches is dependent on the development of efficient DNA vaccine vectors and improved systems for DNA vaccine delivery. DNA vaccine technology may yet prove to be an important asset in an environment where there is a critical need for therapeutic and prophylactic strategies to combat a wide range of disease states.
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Affiliation(s)
- H Oya Alpar
- University of London, School of Pharmacy, UK.
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152
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Abstract
Among several drug delivery systems, liposomal encapsulated anti-cancer agents represent an advanced and versatile technology. Several formulations of liposomal anthracyclines are approved, e.g. for the treatment of metastatic breast cancer (pegylated and non-pegylated liposomal doxorubicin) or AIDS-related Kaposi's sarcoma (pegylated liposomal doxorubicin and liposomal daunorubicin). Meanwhile, virtually all anti-cancer drugs have been encapsulated in liposomes using different technologies. This review will summarize preclinical and clinical data of approved and exemplary emerging liposomal anti-cancer agents.
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Affiliation(s)
- Ralf-Dieter Hofheinz
- Onkologisches Zentrum, III. Medizinische Klinik, Fakultät für Klinische Medizin Mannheim, Universität Heidelberg, Mannheim, Germany.
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153
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Abstract
In the past two decades there have been major advances in the development of liposomal drug delivery systems suitable for applications ranging from cancer chemotherapy to gene therapy. In general, an optimized system consists of liposomes with a diameter of approximately 100 nm that possess a long circulation lifetime (half-life >5 h). Such liposomes will circulate sufficiently long to take advantage of a phenomenon known as disease site targeting, wherein liposomes accumulate at sites of disease, such as tumors, as a result of the leaky vasculature and reduced blood flow exhibited by the diseased tissue. The extended circulation lifetime is achieved by the use of saturated lipids and cholesterol or by the presence of PEG-containing lipids. This chapter will focus on the methodology required for the generation of two very different classes of liposomal carrier systems: those containing conventional small molecular weight (usually anticancer) drugs and those containing larger genetic (oligonucleotide and plasmid DNA) drugs. Initially, we will examine the encapsulation of small, weakly basic drugs within liposomes in response to transmembrane pH and ion gradients. Procedures will be described for the formation of large unilamellar vesicles (LUVs) by extrusion methods and for loading anticancer drugs into LUVs in response to transmembrane pH gradients. Three methods for generating transmembrane pH gradients will be discussed: (1) the use of intravesicular citrate buffer, (2) the use of transmembrane ammonia gradients, and (3) ionophore-mediated generation of pH gradients via transmembrane ion gradients. We will also discuss the loading of doxorubicin into LUVs by formation of drug-metal ion complexes. Different approaches are required for encapsulating macromolecules within LUVs. Plasmid DNA can be encapsulated by a detergent-dialysis approach, giving rise to stabilized plasmid-lipid particles, vectors with potential for systemic gene delivery. Antisense oligonucleotides can be spontaneously entrapped upon electrostatic interaction with ethanol-destabilized cationic liposomes, giving rise to small multilamellar systems known as stabilized antisense-lipid particles (SALP). These vectors have the potential to regulate gene expression.
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Affiliation(s)
- David B Fenske
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada
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154
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Fujisawa S, Kadoma Y, Ishihara M, Atsumi T, Yokoe I. Dipalmitoylphosphatidylcholine (DPPC) and DPPC/Cholesterol Liposomes as Predictors of the Cytotoxicity ofBis‐GMA Related Compounds. J Liposome Res 2004; 14:39-49. [PMID: 15461931 DOI: 10.1081/lpr-120039662] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
In light of recent development, dental materials such as 2, 2-bis [4-2(-hydroxy-3-methacryloyloxypropoxy)phenyl] propane, ( bis-GMA); 2, 2-bis [4-(1-hydroxymethyl-2-methacryloxy)phenyl] propane, (iso-bis-GMA); and triethyleneglycol dimethacrylate, (TEGDMA) were investigated to determine whether their phase transition properties (phase transition temperature, temperature width, cooperativity) could be induced in samples of DPPC or DPPC/cholesterol (CHOL) liposomes using differential scanning calorimetry (DSC). The changes in phase transition properties of DPPC liposomes caused by addition of TEGDMA were greater than those caused by addition of bis-GMA or iso-bis-GMA, but the extent of changes in the properties of DPPC/CHOL (10:1 or 4:1) liposomes declined in the order of bis-GMA > iso-bis-GMA > TEGDMA. The degree of alteration was related to the cytotoxicity of these compounds. DPPC/CHOL liposomes were found to be better predictors of cytotoxicity than DPPC liposomes. Whether the computational approach to studying the molecular mechanism of alteration is applicable using descriptors such as reactivity of energy of the highest occupied molecular orbital (HOMO) and/or lowest unoccupied molecular orbital (LUMO) was investigated, and the data suggested that these descriptors are useful for studying the interactive roles of dental materials.
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Affiliation(s)
- Seiichiro Fujisawa
- Department of Oral Diagnosis, Meikai University School of Dentistry, Sakado, Saitama, Japan.
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155
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Chemotherapeutic engineering: Application and further development of chemical engineering principles for chemotherapy of cancer and other diseases. Chem Eng Sci 2003. [DOI: 10.1016/s0009-2509(03)00234-3] [Citation(s) in RCA: 253] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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156
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Harrington KJ, Syrigos KN, Vile RG. Liposomally targeted cytotoxic drugs for the treatment of cancer. J Pharm Pharmacol 2002; 54:1573-600. [PMID: 12542887 DOI: 10.1211/0022357002243] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Phospholipid spherules composed of lipid bilayer membranes entrapping a central aqueous core were first described more than 30 years ago (Bangham et al 1965). The term liposome was coined in 1968 (Sessa & Weissmann 1968) and the first suggestions that these vesicles might have potential as vehicles for targeted drug delivery for a range of diseases, including cancer, appeared shortly afterwards (Gregoriades et al 1974; Gregoriades 1976a, b). However, the process of turning this expectation into a clinical reality has suffered a number of setbacks and has taken more than a quarter of a century. In the process, new types of liposomes with favourable in-vivo pharmacokinetics and biodistribution patterns have been generated (Lasic & Papahadjopoulos 1995). Many of these preparations have been subjected to extensive examination and an increasing number of agents have entered clinical trials. In this review, we will trace the development of those liposomes that are currently undergoing (or are about to undergo) clinical evaluation.
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Affiliation(s)
- Kevin J Harrington
- Cancer Research UK Targeted Therapy Laboratory, Chester Beatty Laboratories, Institute of Cancer Research, London, UK.
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157
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Walde P, Ichikawa S. Enzymes inside lipid vesicles: preparation, reactivity and applications. BIOMOLECULAR ENGINEERING 2001; 18:143-77. [PMID: 11576871 DOI: 10.1016/s1389-0344(01)00088-0] [Citation(s) in RCA: 438] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
There are a number of methods that can be used for the preparation of enzyme-containing lipid vesicles (liposomes) which are lipid dispersions that contain water-soluble enzymes in the trapped aqueous space. This has been shown by many investigations carried out with a variety of enzymes. A review of these studies is given and some of the main results are summarized. With respect to the vesicle-forming amphiphiles used, most preparations are based on phosphatidylcholine, either the natural mixtures obtained from soybean or egg yolk, or chemically defined compounds, such as DPPC (1,2-dipalmitoyl-sn-glycero-3-phosphocholine) or POPC (1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine). Charged enzyme-containing lipid vesicles are often prepared by adding a certain amount of a negatively charged amphiphile (typically dicetylphosphate) or a positively charged lipid (usually stearylamine). The presence of charges in the vesicle membrane may lead to an adsorption of the enzyme onto the interior or exterior site of the vesicle bilayers. If (i) the high enzyme encapsulation efficiencies; (ii) avoidance of the use of organic solvents during the entrapment procedure; (iii) relatively monodisperse spherical vesicles of about 100 nm diameter; and (iv) a high degree of unilamellarity are required, then the use of the so-called 'dehydration-rehydration method', followed by the 'extrusion technique' has shown to be superior over other procedures. In addition to many investigations in the field of cheese production--there are several studies on the (potential) medical and biomedical applications of enzyme-containing lipid vesicles (e.g. in the enzyme-replacement therapy or for immunoassays)--including a few in vivo studies. In many cases, the enzyme molecules are expected to be released from the vesicles at the target site, and the vesicles in these cases serve as the carrier system. For (potential) medical applications as enzyme carriers in the blood circulation, the preparation of sterically stabilized lipid vesicles has proven to be advantageous. Regarding the use of enzyme-containing vesicles as submicrometer-sized nanoreactors, substrates are added to the bulk phase. Upon permeation across the vesicle bilayer(s), the trapped enzymes inside the vesicles catalyze the conversion of the substrate molecules into products. Using physical (e.g. microwave irradiation) or chemical methods (e.g. addition of micelle-forming amphiphiles at sublytic concentration), the bilayer permeability can be controlled to a certain extent. A detailed molecular understanding of these (usually) submicrometer-sized bioreactor systems is still not there. There are only a few approaches towards a deeper understanding and modeling of the catalytic activity of the entrapped enzyme molecules upon externally added substrates. Using micrometer-sized vesicles (so-called 'giant vesicles') as simple models for the lipidic matrix of biological cells, enzyme molecules can be microinjected inside individual target vesicles, and the corresponding enzymatic reaction can be monitored by fluorescence microscopy using appropriate fluorogenic substrate molecules.
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Affiliation(s)
- P Walde
- Institut für Polymere, ETH-Zentrum, Universitätstrasse 6, CH-8092, Zürich, Switzerland.
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158
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Harrington KJ, Lewanski CR, Stewart JS. Liposomes as vehicles for targeted therapy of cancer. Part 1: preclinical development. Clin Oncol (R Coll Radiol) 2000; 12:2-15. [PMID: 10749014 DOI: 10.1053/clon.2000.9104] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- K J Harrington
- ICRF Oncology Unit, Imperial College of Science, Technology and Medicine, Hammersmith Hospital, London, UK.
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159
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Pinto-Alphandary H, Andremont A, Couvreur P. Targeted delivery of antibiotics using liposomes and nanoparticles: research and applications. Int J Antimicrob Agents 2000; 13:155-68. [PMID: 10724019 DOI: 10.1016/s0924-8579(99)00121-1] [Citation(s) in RCA: 237] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
This review examines current technologies for increasing the bioavailability of antibiotics by means of liposomes or nanoparticles. The main focus is on liposomes. These carriers were preferentially developed because their composition is compatible with biological constituents. Biodegradable polymers in the form of colloidal particles have also been used and show promise for future applications in antimicrobial chemotherapy. The in vivo behaviour of both types of carriers and consequently their therapeutic potential, are determined by their route of administration. Conventional carrier strategies permit the mononuclear phagocyte system to be targeted by intravenous injection of antibiotics. Stealthy strategies avoid major uptake by these cells and extend the systemic presence of these carriers. The purpose of this review is to provide background information in antibiotic targeting gathered from papers published over the last twenty years. It seems clear that such drug carriers (liposomes, nanoparticles) allow increased drug concentration at infected sites but reduce drug toxicity.
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Affiliation(s)
- H Pinto-Alphandary
- UMR CNRS 8612 Faculté de Pharmacie, Université Paris XI, Châtenay-Malabry, France.
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160
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Abstract
A family of mesoporous molecular sieves (denoted MSU-G) with vesiclelike hierarchical structures and unprecedented thermal (1000 degreesC) and hydrothermal stabilities (more than 150 hours at 100 degreesC) associated with high SiO4 cross-linking was prepared through a supramolecular assembly pathway that relies on hydrogen bonding between electrically neutral gemini surfactants of the type CnH2n+1NH(CH2)2NH2 and silica precursors derived from tetraethylorthosilicate. The vesicle shells are constructed of one or more undulated silica sheets that are about 3 nanometers thick with mesopores (average diameters from 2.7 to 4.0 nanometers) running both parallel and orthogonal to the silica sheets, which makes the framework structure bicontinuous and highly accessible. Catalytic metal ion centers [for example, Ti(IV) and Al(III)] have been incorporated into the framework with the retention of hierarchical structure.
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Affiliation(s)
- SS Kim
- Department of Chemistry and Center for Fundamental Materials Research, Michigan State University, East Lansing, MI 48824, USA
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161
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Ansari NH, He Q, Cook JD, Wen J, Srivastava SK. Delivery of liposome-sequestered hydrophobic proteins to lysosomes of normal and Batten disease cells. J Neurosci Res 1997; 47:341-7. [PMID: 9039656 DOI: 10.1002/(sici)1097-4547(19970201)47:3<341::aid-jnr12>3.0.co;2-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
We have developed a method to deliver hydrophobic proteins such as ATP synthase subunit c and ubiquitin to lysosomes of PMN (polymorphonucleocytes) and fibroblasts. ATP synthase subunit c is stored in the lysosomes of various tissues in late infantile and juvenile forms of neuronal ceriod lipofuscinosis, also called Batten disease (BD). Whether this protein storage is due to an abbreviation in protein or in the lysosomal hydrolases of BD is still not clear. We have sequestered this protein and ubiquitin in the lipid membrane of liposomes. The liposomes coated with autologous heat-aggregated IgG or apolipoprotein E when presented to the PMN and fibroblasts, respectively, accumulated in the lysosomes. Both normal and BD PMN degraded 125I-ubiquitin; the rate of degradation was, however, slower by Batten PMN. These studies indicate that a hydrophobic molecule such as subunit c can be delivered to PMN and fibroblasts, and the sequestered proteins are accessible to lysosomal hydrolases. Therefore, this technique can be used to study the metabolism of highly hydrophobic proteins by lysosomes, especially the biochemical mechanism(s) of subunit c storage in BD.
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Affiliation(s)
- N H Ansari
- Department of Human Biological Chemistry and Genetics, University of Texas Medical Branch, Galveston 77555-0647, USA
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162
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Affiliation(s)
- M Ranson
- CRC Department of Medical Oncology, Christie Hospital NHS Trust, Manchester, U.K
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163
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Abstract
Liposomal drug-delivery systems have come of age in recent years, with several liposomal drugs currently in advanced clinical trials or already on the market. It is clear from numerous pre-clinical and clinical studies that drugs, such as antitumor drugs, packaged in liposomes exhibit reduced toxicities, while retaining, or gaining enhanced, efficacy. This results, in part, from altered pharmacokinetics, which lead to drug accumulation at disease sites, such as tumors, and reduced distribution to sensitive tissues. Fusogenic liposomal systems that are under development have the potential to deliver drugs intracellularly, and this is expected to markedly enhance therapeutic activity. Advances in liposome design are leading to new applications for the delivery of new biotechnology products, such as recombinant proteins, antisense oligonucleotides and cloned genes.
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Affiliation(s)
- A Chonn
- INEX Pharmaceuticals Corporation, Vancouver, Canada
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164
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Abstract
An autobiographical account of the liposome, from the perplexities of a blood smear to the growth of a multi-million pound business.
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Affiliation(s)
- A D Bangham
- Institute of Animal Physiology, Babraham, Cambridge
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165
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Buttgereit F, Brand MD, Müller M. Effects of methylprednisolone on the energy metabolism of quiescent and ConA-stimulated thymocytes of the rat. Biosci Rep 1993; 13:41-52. [PMID: 7687156 DOI: 10.1007/bf01138177] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The short-term effects of high concentrations of Methylprednisolone (MP) on the energy metabolism of quiescent and Concanavalin A-stimulated rat thymocytes were investigated in vitro. Concanavalin A (ConA) stimulated the respiration rate of quiescent thymocytes by 35%. Addition of more than 0.15 mg MP/10(7) cells to ConA-stimulated cells reversed this respiratory stimulation; in addition, higher concentrations of MP caused a similar progressive decrease in the rate of respiration of both quiescent and ConA-stimulated cells. Similarly, the stimulation of respiration by ConA was greatly reduced in MP-treated cells. MP addition lowered cytoplasmic [Ca2+] and, at high concentrations, abolished the ability of ConA to increase [Ca2+]. Thus MP both reverses and prevents the immediate stimulation of thymocytes by ConA. In quiescent thymocytes, MP strongly inhibited that part of the oxygen consumption used to drive the cycle of Na+ influx across the plasma membrane and Na+ efflux on the Na+K(+)-ATPase, but did not inhibit oxygen consumption used to drive protein synthesis. In ConA-stimulated thymocytes MP had the same effects and also strongly inhibited oxygen consumption dependent on the cycle of Ca2+ influx across the plasma membrane and Ca2+ efflux on the Ca(2+)-ATPase, but had little effect on oxygen consumption used to drive RNA and DNA synthesis. These results show that MP prevents cation cycling in thymocytes (either by preventing cation influx or by inhibiting cation pumps) and prevents mitogenic stimulation of the cells. The high MP concentration required and the speed of onset of the effects (less than 30 s) provide strong evidence that these effects of MP are not mediated by glucocorticoid receptors and subsequent activation of gene expression. They may be caused by direct effects of MP on the properties of the plasma membrane. These effects are considered to be, at least partially, responsible for the beneficial results that currently have been obtained using MP megadoses in various clinical situations.
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Affiliation(s)
- F Buttgereit
- Department of Internal Medicine, Humboldt University (Charité), Berlin, Germany
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166
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167
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Fujisawa S, Kadoma Y, Komoda Y. 1H and 13C NMR studies of the interaction of eugenol, phenol, and triethyleneglycol dimethacrylate with phospholipid liposomes as a model system for odontoblast membranes. J Dent Res 1988; 67:1438-41. [PMID: 3183163 DOI: 10.1177/00220345880670111501] [Citation(s) in RCA: 60] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
To clarify the mechanism of the interaction of eugenol with odontoblast membranes compared with that of phenol and triethyleneglycol dimethacrylate (TEGDMA), we employed dipalmitoylphosphatidylcholine (DPPC) liposomes as a model system for odontoblast membranes. 1H and 13C nuclear magnetic resonance spectroscopy (NMR) was used as the spectroscopic approach in the study of this interaction. No signals of 1H and 13C due to eugenol in the DPPC/eugenol liposomes were observed, indicating that the mobility of eugenol was strongly disturbed by DPPC and that eugenol did not diffuse from the liposomes once it was incorporated. The change in chemical shifts due to phenol between the free state and the DPPC/phenol liposomes was not found, indicating that phenol resides in the aqueous phase or near the surfaces of liposomes, its interaction being markedly weaker than that of eugenol. The signals due to TEGDMA in the DPPC/TEGDMA liposomes were split into two peaks: a lower-field peak (free TEGDMA) and a higher-field one (membrane-bound TEGDMA). TEGDMA with ethyleneglycol groups seemed to be activated on the liposomes as a surfactant-like agent.
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Affiliation(s)
- S Fujisawa
- School of Dentistry, Tokyo Medical and Dental University, Japan
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168
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Baeza I, Ibañez M, Lazcano A, Santiago C, Arguello C, Wong C, Oró J. Liposomes with polyribonucleotides as model of precellular systems. ORIGINS LIFE EVOL B 1987; 17:321-31. [PMID: 3627767 DOI: 10.1007/bf02386471] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
A study of the encapsulation of poly(U) and poly(C) within liposomes made from dipalmitoylphosphatidyl choline (DPPC), from egg yolk phosphatidyl choline (PC), and from PC with cholesterol (CHOL) was made. The liposomes were prepared under anoxic conditions following the reverse-phase evaporation method. Determinations showed that 36 to 70% of the available lipids form liposomes and 2 to 5% of the polyribonucleotides can be entrapped by liposomes. The encapsulation of polyribonucleotides has also been measured in the presence of urea, cyanamide and Zn++, condensing agents in prebiotic polymerization reactions. DPPC and PC:CHOL liposomes were formed in the presence of 1.0 M urea, although no PC liposomes were formed. The three types of liposomes were readily formed at 0.01 M urea, but in no case an enhancement of encapsulation efficiency of poly(U) was observed due to the presence of urea. Similar results were obtained with cyanamide. An enhanced encapsulation of poly(U) by the three types of liposomes was observed when Zn++ was in the range of 0.001 to 0.01 M. Poly(U) encapsulation was 15 to 25 times higher when liposomes were prepared from DPPC at 0.01 M Zn++. Similar results were obtained with poly(C). The advantages of DPPC-polyribonucleotide liposomes as precellular systems are discussed.
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169
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Choi SJ, Schumacher HR, Clayburne G, Rothfuss MS, Sieck M. Liposome-induced synovitis in rabbits. Light and electron microscopic studies. ARTHRITIS AND RHEUMATISM 1986; 29:889-96. [PMID: 3741501 DOI: 10.1002/art.1780290711] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
A solution containing synthetic liposomes was injected into rabbit knee joints. This induced light and electron microscopic findings very similar to those seen in acute or chronic arthritis, not attributable to any mechanism other than to spherulites, in humans. Synovial fluid studies revealed leukocytosis and abundant extracellular, and/or intracellular positively birefringent spherulites, which appeared as Maltese crosses. Histologic studies of synovial membranes showed infiltration with polymorphonuclear neutrophils or mononuclear cells. Examination of the synovial fluids and synovial membranes by electron microscopy revealed intracellular multilayered membranous arrays of varying shapes. These observations suggest that further consideration should be given to a phlogistic role for similar spherulites found in some patients.
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170
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Deamer DW. Role of amphiphilic compounds in the evolution of membrane structure on the early earth. ORIGINS LIFE EVOL B 1986; 17:3-25. [PMID: 3796965 DOI: 10.1007/bf01809809] [Citation(s) in RCA: 72] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
A variety of amphiphilic compounds have the capacity to self-assemble into membranous structures in the form of bilayers. The earliest cellular organisms must have incorporated such compounds into boundary membranes, and this review discusses amphiphilic components of the prebiotic environment which would be candidates. One possible source is organic material carried to the earth's surface by meteoritic infall. To test this, we have extracted and analysed non-polar substances from the Murchison carbonaceous chondrite, and found that at least some of the components can produce boundary structures which resemble membranes. This observation suggests that membranous boundary structures were present on the early earth, and available to participate in the origin and evolution of the first cellular forms of life.
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171
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Deliconstantinos G. Cortisol effect on (Na+ + K+)-stimulated ATPase activity and on bilayer fluidity of dog brain synaptosomal plasma membranes. Neurochem Res 1985; 10:1605-13. [PMID: 3003615 DOI: 10.1007/bf00988602] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The binding of [14C]cortisol into dog brain synaptosomal plasma membranes (SPM) follows an exponential path described by the general formula y = a.ebx. The specific activity of the SPM-bound (Na+ + K+)-stimulated ATPase was linearly increased at different concentrations of cortisol. Changes in the allosteric properties of (Na+ + K+)-stimulated ATPase by fluoride (F-) (i.e. changes of Hill coefficients) indicate that cortisol increases the membrane fluidity. The fluorescence anisotropy of 1,6-diphenyl-1,3,5-hexatriene-labeled SPM decreased in cortisol treated SPM compared to untreated (control) SPM, which is consistent with a general increase in membrane fluidity. This increase of fluidity by cortisol may play a role in the physiological effects of this hormone in the brain.
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172
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Rabovsky J, Marion KJ, Resnick H. Hydrocarbon solvents: effect on calcium mediated events in liposomes. Chem Phys Lipids 1985. [DOI: 10.1016/0009-3084(85)90071-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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173
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Vonderhaar BK, Bhattacharya A, Alhadi T, Liscia DS, Andrew EM, Young JK, Ginsburg E, Bhattacharjee M, Horn TM. Isolation, characterization, and regulation of the prolactin receptor. J Dairy Sci 1985; 68:466-88. [PMID: 2985666 DOI: 10.3168/jds.s0022-0302(85)80847-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The prolactin, or lactogenic hormone, receptor has been purified (approximately 80%) from lactating mouse liver and human term placenta by the nondenaturing zwitterionic detergent 3-[(3-cholamidopropyl)-dimethylammonio]-1-propane sulfonate and a prolactin affinity column. The isolated "core-binding unit" has a molecular weight of 37,000 +/- 2,000 daltons. It retains the specificity for lactogenic hormones and binds prolactin with an affinity (Ka = 2 to 6 X 10(9) M-1) similar to that of the receptor as it occurs in its membranous environment (Ka = 3 to 5 X 10(9) M-1). Whether this "core-binding unit" exists on the cell surface in a cryptic or active form is influenced greatly by its association with other membrane proteins and the concentration of phosphatidylcholine within its local membranous environment.
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MESH Headings
- Animals
- Cholic Acids
- Chromatography, Affinity
- Concanavalin A/pharmacology
- Electrophoresis, Polyacrylamide Gel
- Female
- Humans
- Immunodiffusion
- Liver/analysis
- Mice
- Mice, Inbred Strains
- Microscopy, Electron
- Microsomes/analysis
- Microsomes, Liver/analysis
- Models, Biological
- Molecular Weight
- Phospholipids/metabolism
- Placenta/analysis
- Prolactin/metabolism
- Protein Binding
- Rabbits
- Rats
- Rats, Inbred Strains
- Receptors, Cell Surface/isolation & purification
- Receptors, Cell Surface/metabolism
- Receptors, Prolactin
- Solubility
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174
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Thunnissen IE, Marani E, Rietveld WJ. 'Homing' of Lucifer Yellow liposomes into hypothalamic neurons: a combined neuroanatomical Golgi and tracing technique. J Neurosci Methods 1984; 12:113-23. [PMID: 6084792 DOI: 10.1016/0165-0270(84)90010-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Liposomes are combined with Lucifer Yellow in order to evoke neuronal uptake of this fluorescent dye in the medial basal hypothalamus. Lucifer Yellow liposomes are preferentially taken up by hypothalamic neurons. The dye spreads into the dendrites and axons, producing Golgi-revealing views of several neurons near the injection site in which both untrapped and liposome-entrapped Lucifer Yellow has been microiontophoretically administered. The capriciousness of the labeled neurons makes it possible to study the dendritic arborization and spines, while the axon with its collaterals can be followed to their targets. Moreover, the dye is also taken up retrogradely. When retrograde uptake over great distances occurs, the Golgi-like appearance is missing, because only then is perikaryal labeling found.
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175
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Fujisawa S, Kadoma Y, Masuhara E. A calorimetric study of the interaction of synthetic phospholipid liposomes with vinyl monomers, acrylates and methacrylates. ACTA ACUST UNITED AC 1984; 18:1105-14. [PMID: 6544795 DOI: 10.1002/jbm.820180912] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Mono-, di-, and trimethacrylates (monomers) are widely used in dentistry as restorative materials, adhesives, prosthetic devices, etc. It is known that the residual monomers released from the cured resin have been implicated in toxicological effects. In order to monitor the biological actions at the membrane level induced by monomers, we studied the changes in the phase transition temperature (T) and enthalpy (delta H) of dipalmitoyl-phosphatidylcholine liposomes induced by 37 different monomers using differential scanning calorimetry (DSC). The monomers that caused large changes in the T and delta H were vinyl monomers; acrylates; monomethacrylates that contain hydroxy, carbonyl, amino and phenyl groups; dimethacrylates with short-chain substituents; and aliphatic trimethacrylates. It is suggested that the changes in the T and delta H values may be due not only to hydrophobic interactions, but also to interactions induced by the double bonds or the functional groups in the monomers. On the other hand, methacrylates with simple alkyl ester linkage and dimethacrylates with bisphenol A groups exhibited the smallest changes. The changes in the T and delta H induced by highly hydrophobic methacrylates were small due to their slower interaction. These changes in transition properties of liposomes seem to be related to biological activities.
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176
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Ganesan M, Weiner N, Flynn G, Ho N. Influence of liposomal drug entrapment on percutaneous absorption. Int J Pharm 1984. [DOI: 10.1016/0378-5173(84)90225-4] [Citation(s) in RCA: 102] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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177
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Edwards JC, Chapman D, Cramp WA, Yatvin MB. The effects of ionizing radiation on biomembrane structure and function. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 1984; 43:71-93. [PMID: 6374762 DOI: 10.1016/0079-6107(84)90004-x] [Citation(s) in RCA: 99] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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178
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Espinola LG, Wider EA, Stella AM, Del C. Batlle AM. Enzyme replacement therapy in porphyrias—II: Entrapment of δ-aminolaevulinate dehydratase in liposomes. ACTA ACUST UNITED AC 1983. [DOI: 10.1016/0020-711x(83)90115-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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179
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Abstract
Interactions of 14 organic compounds, such as phenols, aromatic carboxylic acids, steroids, and methacrylates with the multi-lamellar lecithin-cholesterol liposomes, were monitored in biological systems. It was found that their actions with our artificial liposomes were quite similar to those of biological membranes described previously.
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180
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Koŕeh K, Seligman ML, Flamm ES, Demopoulos HB. Lipid antioxidant properties of naloxone in vitro. Biochem Biophys Res Commun 1981; 102:1317-22. [PMID: 7317053 DOI: 10.1016/s0006-291x(81)80155-6] [Citation(s) in RCA: 38] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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181
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Hardy JG, Wilson CG. Radionuclide imaging in pharmaceutical, physiological and pharmacological research. CLINICAL PHYSICS AND PHYSIOLOGICAL MEASUREMENT : AN OFFICIAL JOURNAL OF THE HOSPITAL PHYSICISTS' ASSOCIATION, DEUTSCHE GESELLSCHAFT FUR MEDIZINISCHE PHYSIK AND THE EUROPEAN FEDERATION OF ORGANISATIONS FOR MEDICAL PHYSICS 1981; 2:71-121. [PMID: 6802552 DOI: 10.1088/0143-0815/2/2/006] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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182
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183
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Perrin DD, Stünzi H. Viral chemotherapy: antiviral actions of metal ions and metal-chelating agents. Pharmacol Ther 1981; 12:255-97. [PMID: 7232497 DOI: 10.1016/0163-7258(81)90083-8] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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184
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Rosenqvist E, Michaelsen TE, Vistnes AI. Effect of streptolysin O and digitonin on egg lecithin/cholesterol vesicles. BIOCHIMICA ET BIOPHYSICA ACTA 1980; 600:91-102. [PMID: 6249363 DOI: 10.1016/0005-2736(80)90414-9] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Artificial membrane vesicles (liposomes) have been used to study the lytic mechanism of the bacterial toxin, streptolysin O, compared to that of the well-known plant glycoside, digitonin. Two types of vesicle were prepared: large unilamellar vesicles and multilamellar liposomes. The vesicles were prepared with varying molar ratios of egg lecithin and cholesterol and loaded with the water-soluble spin label, TEMPO-choline chloride. Lysis of the vesicles was registered as release of spin label and monitored by change in the electron spin resonance (ESR) spectrum. In this system digitonin was able to lyse both large unilamellar vesicles and multilamellar liposomes. The effectiveness of lysis increased by increasing the percentage of cholesterol, but even at 0% cholesterol a significant level of lysis was observed by addition of a large enough concentration of digitonin. In contrast, no lysis was detected from multilamellar liposomes after exposure to streptolysin O, even when they consisted of 50 mol% cholesterol. On the other hand, large unilamellar vesicles could be lysed by streptolysin O, provided the cholesterol content was greater than 33%. At 67 mol% cholesterol in the membranes, the degree of lysis was diminished compared to 50%, which appeared to be optimal. This is the first demonstration of liposome lysis by streptolysin O and demonstrates the cholesterol specificity which has previously been shown by inhibition studies.
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185
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Abstract
The distribution of 131I-labelled liposomes with sodium iodide entrapped in the aqueous core has been compared with that of a preparation containing iodinated phospholipid, following i.v. administration to rabbits. Liver uptake was observed initially with both liposomes, but the distribution of the former preparation soon became indistinguishable from that of [131I] sodium iodide. Iodine-131 was still detectable in the liver 150 h after administration of the phospholipid labelled material. Scintigrams showing the distributions of the radionuclides following administration of 131I-labelled liposomes and 99mTc-DTPA liposomes indicate that there may be some biliary clearance.
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186
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Konings AW, Damen J, Trieling WB. Protection of liposomal lipids against radiation induced oxidative damage. INTERNATIONAL JOURNAL OF RADIATION BIOLOGY AND RELATED STUDIES IN PHYSICS, CHEMISTRY, AND MEDICINE 1979; 35:343-50. [PMID: 312791 DOI: 10.1080/09553007914550411] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Liposomes were prepared from phospholipids extracted from biological membranes. A comparison was made between the peroxidation rate in handshake liposomes and in sonicated liposomes. The smaller sonicated liposomes were more vulnerable to peroxidation, probably because of the smaller radius of curvature, which results in a less dense packing of lipid molecules in the bilayer and a facilitated action of water radicals produced by the X-irradiation. High oxygen enhancement ratios were obtained, especially at low dose rates, suggesting the operation of slowly progressing chain reactions initiated by ionizing radiation. Three compounds were tested for their ability to protect the liposomal membranes against lipid peroxidation. The naturally occurring compounds reduced glutathione (GSH) and vitamin E(alpha-T) and the powerful radiation protector cysteamine (MEA). All three molecules could protect the liposomes against peroxidation. The membrane-soluble compound vitamin E was by far the most powerful. About 50 per cent protection was achieved by using 5 X 10(-6) M alpha-T, 10(-4) M GSH and 5 X 10(-4) M MEA. The fatty acid composition of the lipids altered drastically as a result of the irradiation. Arachidonic acid and docosahexanoic acid were the most vulnerable of the fatty acids. Very efficient protection of these polyunsaturated fatty acids could be obtained with relatively low concentrations of vitamin E built into the membranes.
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187
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Lad PM, Preston MS, Welton AF, Nielsen TB, Rodbell M. Effects of phospholipase A2 and filipin on the activation of adenylate cyclase. BIOCHIMICA ET BIOPHYSICA ACTA 1979; 551:368-81. [PMID: 420840 DOI: 10.1016/0005-2736(89)90013-8] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Rat liver plasma membranes were incubated with phospholipase A2 (purified from snake venom) or with filipin, a polyene antibiotic, followed by analysis of the binding of glucagon to receptors, effects of GTP on the glucagon-receptor complex, and the activity and responses of adenylate cyclase to glucagon + GTP, GTP, Gpp(NH)p, and F-. Phospholipase A2 treatment resulted in concomitant lossess of glucagon binding and of activation of cyclase by glucagon + GTP. Greater than 85% of maximal hydrolysis of membrane phospholipids was required before significant effects of phospholipase A2 on receptor binding and activity response to glucagon were observed. The stimulatory effects of Gpp(NH)p or F- remained essentially unaffected even at maximal hydrolysis of phospholipids, whereas the stimulatory effect of GTP was reduced. Detailed analysis of receptor binding indicates that phospholipase A2 treatment affected the affinity but not the number of glucagon receptors. The receptors remain sensitive to the effects of GTP on hormone binding. Filipin also caused marked reduction in activation by glucagon + GTP. However, in contrast to phospholipase A2 treatment, the binding of glucagon to receptors was unaffected. The effect of GTP on the binding process was also not affected. The most sensitive parameter of activity altered by filipin was stimulation by GTP or Gpp(NH)p; basal and fluoride-stimulated activities were least affected. It is concluded from these findings that phospholipase A2 and filipin, as was previously shown with phospholipase C, are valuable tools for differentially affecting the components involved in hormone, guanyl nucleotide, and fluoride action on hepatic adenylate cyclase.
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188
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Seligman ML, Mitamura J, Shera N, Demopoulos HB. CORTICOSTEROID (METHYLPREDNISOLONE) MODULATION OF PHOTOPEROXIDATION BY ULTRAVIOLET LIGHT IN LIPOSOMES. Photochem Photobiol 1979. [DOI: 10.1111/j.1751-1097.1979.tb07089.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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189
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Chapter 24 Liposomes as Drug Carriers. ANNUAL REPORTS IN MEDICINAL CHEMISTRY 1979. [DOI: 10.1016/s0065-7743(08)61369-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register]
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190
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Cowell JL, Bernheimer AW. Role of cholesterol in the action of cereolysin on membranes. Arch Biochem Biophys 1978; 190:603-10. [PMID: 102256 DOI: 10.1016/0003-9861(78)90316-8] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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191
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Weissmann G, Korchak H, Finkelstein M, Smolen J, Hoffstein S. Uptake of enzyme-laden liposomes by animal cells in vitro and in vivo. Ann N Y Acad Sci 1978; 308:235-49. [PMID: 279291 DOI: 10.1111/j.1749-6632.1978.tb22026.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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192
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Kataoka T, Kobayashi T. Enhancement of chemotherapeutic effect by entrapping 1-beta-D-arabinofuranosylcytosine in lipid vesicles and its mode of action. Ann N Y Acad Sci 1978; 308:387-94. [PMID: 279298 DOI: 10.1111/j.1749-6632.1978.tb22036.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
a-beta-D-arabinofuranosylcytosine (ara-C) trapped in multilamellar liposomes exerted enhanced chemotherapeutic effect against L1210 murine leukemia. Among four types of liposomes, the one composed of sphingomyelin, stearylamine and cholesterol was most potent in enhancing chemotherapeutic effect of ara-C. And the findings that ara-C was released gradually from liposome in vitro and that ara-C in liposome was chemotherapeutically effective against subsequently inoculated L1210 cells suggested that slow but long-lasting release of ara-C from liposome was partially responsible for enhanced chemotherapeutic effect.
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193
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194
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Cowell JL, Kim KS, Bernheimer AW. Alteration by cereolysin of the structure of cholesterol-containing membranes. BIOCHIMICA ET BIOPHYSICA ACTA 1978; 507:230-41. [PMID: 414780 DOI: 10.1016/0005-2736(78)90419-4] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
When erythrocyte membranes were treated with cereolysin, negatively stained and examined by electron microscopy, ring and arc-shaped structures were observed in the membrane. The outside diameter of the rings varied from 33 to 50 nm with a border thickness of 6.7 to 8.3 nm. The arcs varied in length from 33 to 170 nm with a border thickness of also 6.7 to 8.3 min. When right-side-out erythrocyte ghosts which had been treated with cereolysin were examined by electron microscopy after freeze-fracture, structures with a diameter of 31 to 63 nm were seen in the fracture face of the exoplasmic half of the membrane, but no alterations were visible in the fracture face of the protoplasmic half of the membrane bilayer. Thus the ring structures did not appear to form holes through the membrane. At cereolysin concentrations above 6 microgram/ml rings and arcs were seen when purified toxin alone was examined. At or below 6 microgram/ml toxin rings and arcs were seen only if toxin was incubated with free or membrane-bound cholesterol. Our interpretation is that cereolysin tends to aggregate into ring and arc-shaped structures, and that the tendency to aggregate is increased by cholesterol. Rings and arcs were not seen when erythrocyte ghosts were treated with low, but lytic amounts of cereolysin that significantly altered the premeability of the ghosts.
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195
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Li KP. Dynamics of the desolvating droplet in a laminar flame. Anal Chem 1977. [DOI: 10.1021/ac50021a048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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196
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D'Orazio P, Rechnitz GA. Ion electrode measurements of complement and antibody levels using marker-loaded sheep red blood cell ghosts. Anal Chem 1977; 49:2083-6. [PMID: 907162 DOI: 10.1021/ac50021a047] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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197
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Schiffman FJ, Klein I. Rapid induction of amphotericin B sensitivity in L1210 leukaemia cells by liposomes containing ergosterol. Nature 1977; 269:65-6. [PMID: 561318 DOI: 10.1038/269065a0] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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198
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Gutteridge JM. The measurement of malondialdehyde in peroxidised ox-brain phospholipid liposomes. Anal Biochem 1977; 82:76-82. [PMID: 907133 DOI: 10.1016/0003-2697(77)90136-1] [Citation(s) in RCA: 85] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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199
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Gregoriadis G, Neerunjun DE, Hunt R. Fate of a liposome-associated agent injected into normal and tumour-bearing rodents. Attempts to improve localization in tumour tissues. Life Sci 1977; 21:357-69. [PMID: 70733 DOI: 10.1016/0024-3205(77)90516-1] [Citation(s) in RCA: 101] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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200
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Weissmann G, Cohen C, Hoffstein S. Introduction of enzymes, by means of liposomes, into non-phagocytic human cells in vitro. BIOCHIMICA ET BIOPHYSICA ACTA 1977; 498:375-85. [PMID: 884159 DOI: 10.1016/0304-4165(77)90276-8] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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