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Gomes MAGB, Bauduin A, Le Roux C, Fouinneteau R, Berthe W, Berchel M, Couthon H, Jaffrès PA. Synthesis of ether lipids: natural compounds and analogues. Beilstein J Org Chem 2023; 19:1299-1369. [PMID: 37701305 PMCID: PMC10494250 DOI: 10.3762/bjoc.19.96] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Accepted: 08/17/2023] [Indexed: 09/14/2023] Open
Abstract
Ether lipids are compounds present in many living organisms including humans that feature an ether bond linkage at the sn-1 position of the glycerol. This class of lipids features singular structural roles and biological functions. Alkyl ether lipids and alkenyl ether lipids (also identified as plasmalogens) correspond to the two sub-classes of naturally occurring ether lipids. In 1979 the discovery of the structure of the platelet-activating factor (PAF) that belongs to the alkyl ether class of lipids increased the interest in these bioactive lipids and further promoted the synthesis of non-natural ether lipids that was initiated in the late 60's with the development of edelfosine (an anticancer drug). More recently, ohmline, a glyco glycero ether lipid that modulates selectively SK3 ion channels and reduces in vivo the occurrence of bone metastases, and other glyco glycero ether also identified as GAEL (glycosylated antitumor ether lipids) that exhibit promising anticancer properties renew the interest in this class of compounds. Indeed, ether lipid represent a new and promising class of compounds featuring the capacity to modulate selectively the activity of some membrane proteins or, for other compounds, feature antiproliferative properties via an original mechanism of action. The increasing interest in studying ether lipids for fundamental and applied researches invited to review the methodologies developed to prepare ether lipids. In this review we focus on the synthetic method used for the preparation of alkyl ether lipids either naturally occurring ether lipids (e.g., PAF) or synthetic derivatives that were developed to study their biological properties. The synthesis of neutral or charged ether lipids are reported with the aim to assemble in this review the most frequently used methodologies to prepare this specific class of compounds.
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Affiliation(s)
| | - Alicia Bauduin
- Univ. Brest, CNRS, CEMCA UMR 6521, 6 Avenue Victor Le Gorgeu, 29238 Brest, France
| | - Chloé Le Roux
- Univ. Brest, CNRS, CEMCA UMR 6521, 6 Avenue Victor Le Gorgeu, 29238 Brest, France
| | - Romain Fouinneteau
- Univ. Brest, CNRS, CEMCA UMR 6521, 6 Avenue Victor Le Gorgeu, 29238 Brest, France
| | - Wilfried Berthe
- Univ. Brest, CNRS, CEMCA UMR 6521, 6 Avenue Victor Le Gorgeu, 29238 Brest, France
| | - Mathieu Berchel
- Univ. Brest, CNRS, CEMCA UMR 6521, 6 Avenue Victor Le Gorgeu, 29238 Brest, France
| | - Hélène Couthon
- Univ. Brest, CNRS, CEMCA UMR 6521, 6 Avenue Victor Le Gorgeu, 29238 Brest, France
| | - Paul-Alain Jaffrès
- Univ. Brest, CNRS, CEMCA UMR 6521, 6 Avenue Victor Le Gorgeu, 29238 Brest, France
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Konstantinova ID, Serebrennikova GA. Positively charged lipids: structure, methods of synthesis and applications. RUSSIAN CHEMICAL REVIEWS 2007. [DOI: 10.1070/rc1996v065n06abeh000304] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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3
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Dessing MC, Knapp S, Florquin S, de Vos AF, van der Poll T. CD14 facilitates invasive respiratory tract infection by Streptococcus pneumoniae. Am J Respir Crit Care Med 2006; 175:604-11. [PMID: 17185649 DOI: 10.1164/rccm.200606-824oc] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
RATIONALE CD14 is a pattern recognition receptor that can interact with a variety of bacterial ligands. During gram-negative infection, CD14 plays an important role in the induction of a protective immune response by virtue of its capacity to recognize lipopolysaccharide in the bacterial cell wall. Knowledge of the contribution of CD14 to host defense against gram-positive infections is limited. OBJECTIVES To study the role of CD14 in gram-positive bacterial pneumonia. METHODS CD14 knockout (KO) and normal wild-type (WT) mice were intranasally infected with Streptococcus pneumoniae. MEASUREMENTS AND MAIN RESULTS CD14 KO mice demonstrated a strongly reduced lethality, which was accompanied by a more than 10-fold lower bacterial load in lung homogenates but not in bronchoalveolar lavage fluid at 48 hours after infection. Strikingly, CD14 KO mice failed to develop positive blood cultures, whereas WT mice had positive blood cultures from 24 hours onward and eventually invariably had evidence of systemic infection. Lung inflammation was attenuated in CD14 KO mice at 48 hours after infection, as evaluated by histopathology and cytokine and chemokine levels. Intrapulmonary delivery of recombinant soluble CD14 to CD14 KO mice rendered them equally susceptible to S. pneumoniae as WT mice, resulting in enhanced bacterial growth in lung homogenates and bacteremia, indicating that the presence of soluble CD14 in the bronchoalveolar compartment is sufficient to cause invasive pneumococcal disease. CONCLUSION These data suggest that S. pneumoniae uses (soluble) CD14 present in the bronchoalveolar space to cause invasive respiratory tract infection.
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Affiliation(s)
- Mark C Dessing
- Center for Infection and Immunity Amsterdam, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
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Hadváry P, Weller T. Conformationally Restricted Analogs of Platelet-Activating Factor (PAF). Helv Chim Acta 2004. [DOI: 10.1002/hlca.19860690814] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Bhattacharya S, Subramanian M. Synthesis of novel phosphatidylcholine lipids with fatty acid chains bearing aromatic units. Generation of oxidatively stable, fluid phospholipid membranes. Tetrahedron Lett 2002. [DOI: 10.1016/s0040-4039(02)00758-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Meyers MJ, Sun J, Carlson KE, Marriner GA, Katzenellenbogen BS, Katzenellenbogen JA. Estrogen receptor-beta potency-selective ligands: structure-activity relationship studies of diarylpropionitriles and their acetylene and polar analogues. J Med Chem 2001; 44:4230-51. [PMID: 11708925 DOI: 10.1021/jm010254a] [Citation(s) in RCA: 544] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Through an effort to develop novel ligands that have subtype selectivity for the estrogen receptors alpha (ERalpha) and beta (ERbeta), we have found that 2,3-bis(4-hydroxyphenyl)propionitrile (DPN) acts as an agonist on both ER subtypes, but has a 70-fold higher relative binding affinity and 170-fold higher relative potency in transcription assays with ERbeta than with ERalpha. To investigate the ERbeta affinity- and potency-selective character of this DPN further, we prepared a series of DPN analogues in which both the ligand core and the aromatic rings were modified by the repositioning of phenolic hydroxy groups and by the addition of alkyl substituents and nitrile groups. We also prepared other series of DPN analogues in which the nitrile functionality was replaced with acetylene groups or polar functions, to mimic the linear geometry or polarity of the nitrile, respectively. To varying degrees, all of the analogues show preferential binding affinity for ERbeta (i.e., they are ERbeta affinity-selective), and many, but not all of them, are also more potent in activating transcription through ERbeta than through ERalpha (i.e., they are ERbeta potency-selective). meso-2,3-Bis(4-hydroxyphenyl)succinonitrile and dl-2,3-bis(4-hydroxyphenyl)succinonitrile are among the highest ERbeta affinity-selective ligands, and they have an ERbeta potency selectivity that is equivalent to that of DPN. The acetylene analogues have higher binding affinities but somewhat lower selectivities than their nitrile counterparts. The polar analogues have lower affinities, and only the fluorinated polar analogues have substantial affinity selectivities. This study suggests that, in this series of ligands, the nitrile functionality is critical to ERbeta selectivity because it provides the optimal combination of linear geometry and polarity. Furthermore, the addition of a second nitrile group beta to the nitrile in DPN or the addition of a methyl substitutent at an ortho position on the beta-aromatic ring increases the affinity and selectivity of these compounds for ERbeta. These ERbeta-selective compounds may prove to be valuable tools in understanding the differences in structure and biological function of ERalpha and ERbeta.
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Affiliation(s)
- M J Meyers
- Department of Chemistry, University of Illinois, Urbana, Illinois 61801, USA
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Abstract
Streptococcus pneumoniae infection and disease have been modeled in several animal species including infant and adult mice, infant and adult rats, infant Rhesus monkeys, and adolescent and adult chinchillas. Most are models of sepsis arising from intravenous or intraperitoneal inoculation of bacteria, and a few were designed to study disease arising from intranasal infection. Chinchillas provide the only animal model of middle ear pneumococcal infection in which the disease can be produced by very small inocula injected into the middle ear (ME) or intranasally, and in which the disease remains localized to the ME in most cases. This model, developed at the University of Minnesota in 1975, has been used to study pneumococcal pathogenesis at a mucosal site, immunogenicity and efficacy of pneumococcal capsular polysaccharide (PS) vaccine antigens, and the kinetics and efficacy of antimicrobial drugs. Pathogenesis experiments in the chinchilla model have revealed variation in ME virulence among different pneumococcal serotypes, enhancement of ME infection during concurrent intranasal influenza A virus infections, and natural resolution of pneumococcal otitis media (OM) without intervention. Research has explored the relative contribution of pneumococcal and host products to ME inflammation. Pneumococcal cell wall components and pneumolysin have been studied in the model. Host inflammatory responses studied in the chinchilla ME include polymorphonuclear leukocyte oxidative products, hydrolytic enzymes, cytokine and eicosanoid metabolites, and ME epithelial cell adhesion and mucous glycoprotein production. Both clinical (tympanic membrane appearance) and histopathology (ME, Eustachian tube, inner ear) endpoints can be quantified. Immunologic and inflammatory studies have been facilitated by the production of affinity-purified antichinchilla immunoglobulin G (IgG), IgM, and secretory IgA polyclonal antibody reagents, and the identification of cross-reactivity between human and chinchilla cytokines, and between guinea pig and chinchilla C3. Alteration of ME mucosa by pneumococcal neuraminidase and alteration of ME epithelial cell (MEEC) surface carbohydrates during intranasal pneumococcal infection have been demonstrated. Pathogenesis studies have been aided by cultured chinchilla MEEC systems, in which the ability of platelet activating factor and interleukin (IL)-1 beta to stimulate epithelial mucous glycoprotein synthesis has recently been demonstrated. Because chronic OM with effusion is characterized by presence of large amounts of mucous glycoprotein in the ME, pneumococcus may have an important role in both acute and chronic ME disease. Both unconjugated PS and PS-protein-conjugated vaccines are immunogenic after intramuscular administration without adjuvant in chinchillas. Passive protection studies with human hyperimmune immunoglobulin demonstrated that anti-PS IgG alone is capable of protecting the chinchilla ME from direct ME challenge with pneumococci. Active PS immunization studies demonstrated protection following direct ME and intranasal pneumococcal challenge with and without concurrent influenza A virus infection. An attenuated influenza A virus vaccine also showed protection for pneumococcal OM. Antimicrobial treatment of acute OM has been based almost exclusively on empirical drug use and clinical trials without a foundation of ME pharmacokinetics. Studies in the chinchilla model have started to bring a rational basis to drug selection and dosing. Microassays have been developed using high-pressure liquid chromatography for many relevant drugs. Studies have explored the in vivo ME response in pneumococcal OM to antimicrobial drugs at supra- and sub-minimum inhibitory concentration (MIC), the effect of concurrent influenza A virus infection on ME drug penetration, and the effect of treatment on sensorineural hearing loss produced by pneumococcal OM.
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Affiliation(s)
- G S Giebink
- Otitis Media Research Center, University of Minnesota School of Medicine, Minneapolis 55455, USA
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de Boer AG, Breimer DD. Cytokines and blood-brain barrier permeability. PROGRESS IN BRAIN RESEARCH 1998; 115:425-51. [PMID: 9632945 DOI: 10.1016/s0079-6123(08)62045-2] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- A G de Boer
- Division of Pharmacology, Leiden/Amsterdam Center for Drug Research, Leiden University, Sylvius Laboratories, The Netherlands
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Affiliation(s)
- E I Tuomanen
- Laboratory of Molecular Infectious Diseases, Rockefeller University, New York, New York 10021, USA
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Cundell DR, Gerard NP, Gerard C, Idanpaan-Heikkila I, Tuomanen EI. Streptococcus pneumoniae anchor to activated human cells by the receptor for platelet-activating factor. Nature 1995; 377:435-8. [PMID: 7566121 DOI: 10.1038/377435a0] [Citation(s) in RCA: 501] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The Gram-positive bacterium Streptococcus pneumoniae is a major cause of pneumonia, sepsis and meningitis. Although the invasive disease is severe, some 40% of individuals harbour the pneumococcus in the nasopharynx asymptomatically. Here we investigate the molecular elements of the encounter between host and pathogen that distinguish these different outcomes. We show that inflammatory activation of human cells shifts the targeting of the pneumococcus to a new receptor, that for the G-protein-coupled platelet-activating factor (PAF). Only virulent pneumococci engage the PAF receptor. Attachment of the bacterial phosphorylcholine to the PAF receptor enhanced adherence, which was coupled to invasion of endothelial, epithelial and PAF-receptor-transfected cells. This progression could be arrested in vitro and in vivo by PAF-receptor-specific antagonists, suggesting a possible approach to therapy.
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Affiliation(s)
- D R Cundell
- Laboratory of Molecular Infectious Diseases, Rockefeller University, New York, New York 10021-6399, USA
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Summers JB, Albert DH. Platelet activating factor antagonists. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 1995; 32:67-168. [PMID: 7748804 DOI: 10.1016/s1054-3589(08)61012-1] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- J B Summers
- Abbott Laboratories, Abbott Park, Illinois 60064, USA
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Abstract
The interactions between pneumococcal surface components and host defence systems that initiate pneumococcal meningitis have been studied in considerable molecular detail over the past decade. In this sense, the pneumococcus has served as a prototype for the unravelling of the genesis of inflammation caused by gram-positive bacteria. This review outlines the progression of these early events involving the cytokine cascade, the coagulation cascade, and leukocyte migration, and relates these processes to the production of blood-brain barrier permeability, the hallmark of injury in meningitis. This new understanding has radically altered the therapy of disease with the promise of greatly improved outcome.
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Affiliation(s)
- B Spellerberg
- Laboratory of Molecular Infectious Diseases, Rockefeller University, New York, NY 10021
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13
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Platelet activation factor analogs and antagonists. Pharm Chem J 1994. [DOI: 10.1007/bf02285396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Affiliation(s)
- F Paltauf
- Institut für Biochemie und Lebensmittelchemie der Technischen Universität Graz, Austria
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Kohler C, Carroll M, Tarrant E, Torley L, Wissner A. Effect of a series of 1-alkyl ether lipids on inhibition of phospholipase A2 activity and PAF responses. Inflammation 1993; 17:245-61. [PMID: 8330926 DOI: 10.1007/bf00918988] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Several 1-alkyl ether lipids were studied for their ability to inhibit PLA2 and antagonize PAF responses. Studies with synthetic micellar substrate (1-stearyl-2-arachidonyl phosphocholine), at concentrations ranging from 0.02 to 1000 microM, demonstrate that CL 118326 inhibits porcine pancreatic PLA2 in vitro. As the substrate concentration increases, there is a dose-dependent increase in the IC50 value (IC50 ranges: 1.6-84.6 micrograms/ml or 2.6-137 microM). CL 118326 inhibits mammalian pancreatic PLA2, but not snake or bee venom PLA2. CL 118326 inhibits thrombin (IC50 = 7.9 microM), but not Na arachidonate- (IC50 > 100 microM) induced platelet aggregation, indicative of inhibition of cellular PLA2. CL 118326 inhibits other PLA2-dependent processes such as antigen-induced leukotriene (LTC4) release (IC50 = 2.3 micrograms/ml or 3.8 microM) and histamine release (IC50 = 1.4 micrograms/ml or 2.2 microM) in basophil-enriched WBCs. Intradermal coinjection of CL 118326 (10 micrograms) with PLA2 into guinea pig skin inhibits pancreatic PLA2-induced increase in vascular permeability and leakage, but not snake or bee venom PLA2-induced leakage. CL 118326 shows no PAF-like agonist activity in stimulating rabbit platelet-rich plasma. It inhibits PAF-induced aggregation (IC50 = 5.8 microM), but not ADP-induced aggregation. CL 118326 has greater efficacy as a PLA2 inhibitor than as a PAF antagonist since the IC50-substrate concentration ratio for PLA2 inhibition is < or = 1.0 at substrate concentrations of 10-1000 microM while the IC50-agonist ratio for PAF antagonism is > 100. Results for four other compounds related to CL 118326 are also presented.
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Affiliation(s)
- C Kohler
- Oncology and Inflammation Section, Lederle Labs American Cyanamid Co., Pearl River, New York 10965
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Cabellos C, MacIntyre DE, Forrest M, Burroughs M, Prasad S, Tuomanen E. Differing roles for platelet-activating factor during inflammation of the lung and subarachnoid space. The special case of Streptococcus pneumoniae. J Clin Invest 1992; 90:612-8. [PMID: 1322943 PMCID: PMC443140 DOI: 10.1172/jci115900] [Citation(s) in RCA: 77] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Although well-characterized in the lung, the role of platelet-activating factor (PAF) in inflammation in the central nervous system is undefined. Using rabbit models of meningitis and pneumonia, PAF was found to induce significant blood-brain barrier permeability and brain edema at doses five times lower than those required to generate leukocyte recruitment to the subarachnoid space. Both leukocytosis and increased vascular permeability occurred in response to PAF in the lung. Antibody to the CD-18 family of leukocyte adhesion molecules inhibited leukocyte recruitment in response to PAF in the brain (greater than 80%); a similar level of inhibition in the lung required treatment with a combination of a PAF receptor antagonist (L-659,989) and anti-CD18 antibody. Treatment with L-659,989 decreased abnormal cerebrospinal fluid cytochemical values induced by intracisternal challenge with pneumococci but not Haemophilus influenzae, indicating a special role for PAF in pneumococcal disease. Antibodies directed at phosphorylcholine, a unique, shared determinant of bioactivity of PAF and pneumococcal cell wall, obviated the inflammatory potential of both agents. However, no evidence for a direct PAF-like activity of pneumococcal cell wall components was detected in vitro by bioassay using platelets or neutrophils. It is concluded that PAF can induce inflammation in the subarachnoid space. In brain, PAF effects appear to be mediated through CD-18-dependent events, while in lung, PAF effects independent of CD-18 are also evident. At both sites, PAF is of particular clinical importance during inflammation induced by pneumococci apparently due to a unique proinflammatory relationship between the pneumococcal cell wall teichoic acid and PAF.
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Affiliation(s)
- C Cabellos
- Laboratory of Microbiology, Rockefeller University, New York, NY 10021
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Godfroid JJ, Dive G, Lamotte-Brasseur J, Batt JP, Heymans F. PAF receptor structure: a hypothesis. Lipids 1991; 26:1162-6. [PMID: 1668112 DOI: 10.1007/bf02536523] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Different hypotheses of the structure of platelet-activating factor (PAF) receptor based on structure-activity relationships of agonists and antagonists are reviewed. For an agonistic effect, strong hydrophobic interactions and an ether function are required in position-1 of the glycerol backbone; chain length limitations and steric hindrance demand a small group in position-2. The unusual structural properties of non-PAF-like antagonists required 3-D electrostatic potential calculations. This method applied to seven potent antagonists suggests a strong "Cache-orielles" (ear-muff) effect, i.e., two strong electronegative wells (isocontour at -10 Kcal/mole) are located at 180 degrees to each other and at a relatively constant distance. Initial consideration of the "Cache-oreilles" effect implied the structure of a bipolarized cylinder of 10-12 A diameter for the receptor. However, very recent results on studies with agonists and antagonists structurally similar to PAF suggest that the receptor may in fact be a multi-polarized cylinder.
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Affiliation(s)
- J J Godfroid
- Laboratoire de Pharmacochimie Moléculaire, Université Paris 7, France
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Kumar A, Shanker K. Synthesis of 1-O-Alkyl-2-O-Acetyl-Sn-3-glyceryl-3-phosphoryl Choline the Enantiomer of Platelet Activating Factor (PAF). SYNTHETIC COMMUN 1991. [DOI: 10.1080/00397919108021574] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Lamotte-Brasseur J, Dive G, Lamouri A, Heymans F, Godfroid JJ. PAF-receptor. III. Conformational and electronic properties of PAF-like agonists and antagonists. BIOCHIMICA ET BIOPHYSICA ACTA 1991; 1085:91-105. [PMID: 1654112 DOI: 10.1016/0005-2760(91)90236-b] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
In order to compare electronic and conformational properties of PAF-agonists and PAF-antagonists, 14 analogues structurally related to PAF were studied. A common conformation of the glycerol backbone was present in all agonists and all constrained or flexible antagonists. The distinction between agonists and antagonists appears to be casted on position-2 where the folded conformation of the substituent for agonists should be the most probable. In position-3 the gauche conformation can be adopted by all the analysed compounds. The electrostatic potential well at -30 kcal/mol stretches to the carbonyl group in position-2 in the folded conformation of the agonists. On the contrary, in constrained antagonists, a second negative zone appears around the carbamate group. Given the modelling results, the triethylammonium PAF analogue considered in literature as a weak agonist, was resynthesized and proved to be more potent than previously reported. These experimental results confirm our hypothesis in terms of a common conformation of agonist and antagonist PAF-like molecules.
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Sturk A, ten Cate JW, Hosford D, Mencia-Huerta JM, Braquet P. The synthesis, catabolism, and pathophysiological role of platelet-activating factor. ADVANCES IN LIPID RESEARCH 1989; 23:219-76. [PMID: 2516987 DOI: 10.1016/b978-0-12-024923-7.50010-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- A Sturk
- Department of Hematology, Academic Medical Center, Amsterdam, The Netherlands
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Rosario-Jansen T, Jiang RT, Tsai MD, Hanahan DJ. Phospholipids chiral at phosphorus. Synthesis and stereospecificity of phosphorothioate analogues of platelet-activating factor. Biochemistry 1988; 27:4619-24. [PMID: 3167004 DOI: 10.1021/bi00413a006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
RP and SP isomers of 1-O-hexadecyl-2-acetyl-3-thiophosphocholine (AGEPsC) have been synthesized. The activity of these isomers in platelet aggregation and serotonin secretion was compared with that of 1-O-hexadecyl-2-acetyl-3-phosphocholine (AGEPC). The results show that (SP)-AGEPsC has the same activity as AGEPC within experimental error in both assays. The RP isomer, however, is only 0.6-2% as active as AGEPC in platelet aggregation and serotonin release. The results suggest that the phosphate group of AGEPC is likely to be involved in the interactions with its receptor, at least in the events leading to platelet aggregation and secretion.
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Hofmann B, Ostermann G, Kertscher HP, Till U. Proaggregatory and inhibitory effects of 2-O-ethyl analogues of platelet-activating factor (PAF) on human and rabbit platelets. Thromb Res 1988; 49:415-23. [PMID: 3381200 DOI: 10.1016/0049-3848(88)90244-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
A series of 8 analogues of platelet-activating factor (PAF) in which both the acetyl group and the polar head are changed, were tested for biological activities on human and rabbit platelets in plasma. Two of these compounds, 1-O-hexadecyl-2-O-ethyl-rac-glycero-3-phosphoric acid-5'-trimethylammoniumpentyl ester and 1-O-hexadecyl-2-O-ethyl-rac-glycero-3-phosphoric acid-6'-trimethylammoniumhexyl ester inhibit selectively the PAF-induced aggregation response without showing any agonistic activity. Schild analysis revealed a competitive antagonism and KB values of 4.4 and 10.5 mumol/l, respectively. These results point to a crucial role of the distance between the phosphoryl group and the polar head for expression of PAF-antagonistic properties. Moreover, the substituent at the 2-position was found to influence predominantly the agonistic behaviour.
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Affiliation(s)
- B Hofmann
- Institut für Pathologische Biochemie, Medizinische Akademie, Erfurt, GDR
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Chapter 8 Pulmonary and Antiallergy Agents. ANNUAL REPORTS IN MEDICINAL CHEMISTRY 1987. [DOI: 10.1016/s0065-7743(08)61156-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register]
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Chapter 7 Antihypertensive Agents. ANNUAL REPORTS IN MEDICINAL CHEMISTRY 1987. [DOI: 10.1016/s0065-7743(08)61155-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register]
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Godfroid J, Braquet P. PAF-acether specific binding sites: 1. quantitative SAR study of PAF-acether isosteres. Trends Pharmacol Sci 1986. [DOI: 10.1016/0165-6147(86)90388-3] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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