1
|
Khownium K, Romsaiyud J, Borwornpinyo S, Wongkrasant P, Pongkorpsakol P, Muanprasat C, Boekfa B, Vilaivan T, Ruchirawat S, Limtrakul J. Turn-on fluorescent sensor for the detection of lipopolysaccharides based on a novel bispyrenyl terephtalaldehyde-bis-guanylhydrazone. NEW J CHEM 2019. [DOI: 10.1039/c9nj00323a] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A “turn-on” bispyrenyl sensor for lipopolysaccharide detection with unique molecular conformations exhibits excimer emission with sensitivity down to nanomolar.
Collapse
Affiliation(s)
- Kriangsak Khownium
- Faculty of Medicine
- King Mongkut's Institute of Technology Ladkrabang
- Bangkok
- Thailand
| | - Jariya Romsaiyud
- Department of Chemistry and Center of Excellence for Innovation in Chemistry
- Faculty of Science
- Ramkhamhaeng University
- Bangkok 10240
- Thailand
| | - Suparerk Borwornpinyo
- Department of Biotechnology
- Faculty of Science
- Mahidol University
- Bangkok 10400
- Thailand
| | | | - Pawin Pongkorpsakol
- Department of Physiology
- Faculty of Science
- Mahidol University
- Bangkok 10400
- Thailand
| | - Chatchai Muanprasat
- Excellent Center for Drug Discovery
- Faculty of Science
- Mahidol University
- Bangkok 10400
- Thailand
| | - Bundet Boekfa
- Chemistry Department
- Faculty of Liberal Arts and Science
- Kasetsart University Kamphaeng Saen Campus
- Nakhon Pathom 73140
- Thailand
| | - Tirayut Vilaivan
- Department of Chemistry
- Faculty of Science
- Chulalongkorn University
- Bangkok 10330
- Thailand
| | | | - Jumras Limtrakul
- Department of Materials Science and Engineering
- School of Molecular Science and Engineering
- Vidyasirimedhi Institute of Science and Technology
- Rayong 21210
- Thailand
| |
Collapse
|
2
|
Custelcean R, Williams NJ, Seipp CA, Ivanov AS, Bryantsev VS. Aqueous Sulfate Separation by Sequestration of [(SO
4
)
2
(H
2
O)
4
]
4−
Clusters within Highly Insoluble Imine‐Linked Bis‐Guanidinium Crystals. Chemistry 2015; 22:1997-2003. [DOI: 10.1002/chem.201504651] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Indexed: 01/22/2023]
Affiliation(s)
- Radu Custelcean
- Chemical Sciences Division Oak Ridge National Laboratory Oak Ridge TN 37831-6119 USA
| | - Neil J. Williams
- Chemical Sciences Division Oak Ridge National Laboratory Oak Ridge TN 37831-6119 USA
- Department of Chemistry The University of Tennessee Buehler Hall 1420 Circle Dr. Knoxville TN 37996-1600 USA
| | - Charles A. Seipp
- Chemical Sciences Division Oak Ridge National Laboratory Oak Ridge TN 37831-6119 USA
- Department of Chemistry The University of Texas at Austin 1 University Station-A5300 Austin TX 78712-0165 USA
| | - Alexander S. Ivanov
- Chemical Sciences Division Oak Ridge National Laboratory Oak Ridge TN 37831-6119 USA
| | | |
Collapse
|
3
|
Šekutor M, Glasovac Z, Mlinarić-Majerski K. Neighboring effect in fragmentation pathways of cage guanylhydrazones in the gas phase. J Phys Chem A 2013; 117:2242-52. [PMID: 23413989 DOI: 10.1021/jp311049f] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
ESI-MS/MS investigation of the mono- and bis(guanylhydrazone) derivatives 1-5 based on adamantane and pentacycloundecane (PCU) skeleton was described. Elimination of neutral guanidine is the most abundant reaction channel in the case of 2,4-adamantyl and PCU derivatives 4 and 5, while the elimination of CH2N2 fragment is preferred for other compounds. This was attributed to the cage opening of adamantane or PCU skeletons in the former case leading to the formation of the cyclohexyl- or cyclopropylcarbinyl carbocation stabilized by the conjugation with the guanylhydrazone subunit. The main fragmentation pathways observed experimentally were analyzed by using DFT calculations. All investigated bis(guanylhydrazone)s formed dications and their abundances were found to be proportional to the interguanidine distance in the considered ions. Calculation of the first and the second proton affinities supported qualitative interpretation of the dication abundance. Close contact of two guanidine subunits is thus confirmed to be crucial in determining preferential fragmentation pathway and to suppress formation of the dication.
Collapse
Affiliation(s)
- Marina Šekutor
- Division of Organic Chemistry and Biochemistry, Ruđer Bošković Institute, Bijenička c. 54, P.O. Box 180, 10 002 Zagreb, Croatia
| | | | | |
Collapse
|
4
|
Martínez de Tejada G, Sánchez-Gómez S, Rázquin-Olazaran I, Kowalski I, Kaconis Y, Heinbockel L, Andrä J, Schürholz T, Hornef M, Dupont A, Garidel P, Lohner K, Gutsmann T, David SA, Brandenburg K. Bacterial cell wall compounds as promising targets of antimicrobial agents I. Antimicrobial peptides and lipopolyamines. Curr Drug Targets 2012; 13:1121-30. [PMID: 22664072 DOI: 10.2174/138945012802002410] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2011] [Revised: 09/30/2011] [Accepted: 05/18/2012] [Indexed: 11/22/2022]
Abstract
The first barrier that an antimicrobial agent must overcome when interacting with its target is the microbial cell wall. In the case of Gram-negative bacteria, additional to the cytoplasmic membrane and the peptidoglycan layer, an outer membrane (OM) is the outermost barrier. The OM has an asymmetric distribution of the lipids with phospholipids and lipopolysaccharide (LPS) located in the inner and outer leaflets, respectively. In contrast, Gram-positive bacteria lack OM and possess a much thicker peptidoglycan layer compared to their Gram-negative counterparts. An additional class of amphiphiles exists in Gram-positives, the lipoteichoic acids (LTA), which may represent important structural components. These long molecules cross-bridge the entire cell envelope with their lipid component inserting into the outer leaflet of the cytoplasmic membrane and the teichoic acid portion penetrating into the peptidoglycan layer. Furthermore, both classes of bacteria have other important amphiphiles, such as lipoproteins, whose importance has become evident only recently. It is not known yet whether any of these amphiphilic components are able to stimulate the immune system under physiological conditions as constituents of intact bacteria. However, all of them have a very high pro-inflammatory activity when released from the cell. Such a release may take place through the interaction with the immune system, or with antibiotics (particularly with those targeting cell wall components), or simply by the bacterial division. Therefore, a given antimicrobial agent must ideally have a double character, namely, it must overcome the bacterial cell wall barrier, without inducing the liberation of the pro-inflammatory amphiphiles. Here, new data are presented which describe the development and use of membrane-active antimicrobial agents, in particular antimicrobial peptides (AMPs) and lipopolyamines. In this way, essential progress was achieved, in particular with respect to the inhibition of deleterious consequences of bacterial infections such as severe sepsis and septic shock.
Collapse
|
5
|
Antifungal agents. Part 5: Synthesis and antifungal activities of aminoguanidine derivatives of N-arylsulfonyl-3-acylindoles. Bioorg Med Chem Lett 2010; 20:7274-7. [DOI: 10.1016/j.bmcl.2010.10.084] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2010] [Revised: 09/22/2010] [Accepted: 10/18/2010] [Indexed: 11/22/2022]
|
6
|
Bairwa R, Kakwani M, Tawari NR, Lalchandani J, Ray M, Rajan M, Degani MS. Novel molecular hybrids of cinnamic acids and guanylhydrazones as potential antitubercular agents. Bioorg Med Chem Lett 2010; 20:1623-5. [DOI: 10.1016/j.bmcl.2010.01.031] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2009] [Revised: 12/18/2009] [Accepted: 01/13/2010] [Indexed: 10/19/2022]
|
7
|
Wu G, Fan X, Li L, Wang H, Ding J, Hongbin W, Zhao R, Gou L, Shen Z, Xi T. Interaction of antimicrobial peptide s-thanatin with lipopolysaccharide in vitro and in an experimental mouse model of septic shock caused by a multidrug-resistant clinical isolate of Escherichia coli. Int J Antimicrob Agents 2009; 35:250-4. [PMID: 20045294 DOI: 10.1016/j.ijantimicag.2009.11.009] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2009] [Revised: 11/09/2009] [Accepted: 11/16/2009] [Indexed: 10/20/2022]
Abstract
s-thanatin, an analogue of thanatin, was synthesised by substituting the fifteenth amino acid threonine with serine and showed broad antimicrobial activity against Gram-negative and Gram-positive bacteria. To evaluate its antimicrobial activity against a multidrug-resistant (MDR) clinical isolate as well as its anti-endotoxin activity, its lipopolysaccharide (LPS)-binding and -neutralising activity in vitro and its therapeutic efficacy in an experimental model of septic shock caused by a MDR clinical isolate of Escherichia coli were studied. The ability of s-thanatin to bind or neutralise LPS from E. coli O111:B4 was determined using a quantitative assay kit. Male ICR mice were given an intraperitoneal (i.p.) administration of 2x10(10) colony-forming units of E. coli E79466. Following bacterial challenge, all animals were randomised to receive i.p. administration of saline, 40mg/kg ceftazidime (CAZ), or 40mg/kg CAZ+s-thanatin (10, 20 or 40mg/kg). The results showed that s-thanatin not only completely bound to the LPS (median effective concentration of 17.5microg/mL) but also improved the survival and reduced the number of inoculated bacteria in a mouse model of septic shock. s-thanatin may be an attractive candidate to develop as an anti-MDR bacterial agent.
Collapse
Affiliation(s)
- Guoqiu Wu
- Center of Clinical Laboratory Medicine of Zhongda Hospital, Southeast University, 87 Dingjiaqiao, Nanjing 210009, China.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
8
|
Mesquida N, López-Pérez S, Dinarès I, Frigola J, Mercè R, Holenz J, Pérez R, Burgueño J, Alcalde E. Identification of novel indanylsulfonamide guanylhydrazones as potent 5-HT6 serotonin receptor antagonists. J Med Chem 2009; 52:6153-7. [PMID: 19739674 DOI: 10.1021/jm900796p] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Changing the N,N-(dimethylamino)ethyl side chain in the N-[3-(aminoethyl)inden-5-yl]sulfonamide 5-HT(6) serotonin receptor agonists 1 by a conformationally rigid guanylhydrazone moiety at the indene 3-position led to the identification of the title indanylguanylhydrazones 6, which exhibited excellent binding affinities and an antagonistic response at the 5-HT(6) receptor, with K(i) and IC(50) values in the nanomolar range (K(i) >or= 1.2 nM, IC(50) >or= 47 nM, and I(max) <or= 173%).
Collapse
Affiliation(s)
- Neus Mesquida
- Departament de Farmacologia i Química Terapeutica, Facultat de Farmàcia, Universitat de Barcelona, Barcelona, Spain.
| | | | | | | | | | | | | | | | | |
Collapse
|
9
|
Nguyen TB, Kumar EVKS, Sil D, Wood SJ, Miller KA, Warshakoon HJ, Datta A, David SA. Controlling plasma protein binding: structural correlates of interactions of hydrophobic polyamine endotoxin sequestrants with human serum albumin. Mol Pharm 2009; 5:1131-7. [PMID: 19434925 DOI: 10.1021/mp8001123] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Hydrophobically substituted polyamine compounds, particularly N-acyl or N-alkyl derivatives of homospermine, are potent endotoxin (lipopolysaccharide) sequestrants. Despite their polycationic nature, the aqueous solubilites are limited owing to the considerable overall hydrophobicity contributed by the long-chain aliphatic substituent, but solubilization is readily achieved in the presence of human serum albumin (HSA). We desired first to delineate the structural basis of lipopolyamine-albumin interactions and, second, to explore possible structure-activity correlates in a well-defined, congeneric series of N-alkyl and -acyl homospermine lead compounds. Fluorescence spectroscopic and isothermal titration calorimetry (ITC) results indicate that these compounds appear to bind to HSA via occupancy of the fatty-acid binding sites on the protein. The acyl and carbamate compounds bind HSA the strongest; the ureido and N-alkyl analogues are significantly weaker, and the branched alkyl compound is weaker still. ITC-derived dissociation constants are weighted almost in their entirety by enthalpic deltaH terms, which is suggestive that the polarizability of the carbonyl groups facilitate, at least in large part, their interactions with HSA. The relative affinities of these lipopolyamines toward HSA is reflected in discernible differences in apparent potencies of LPS-sequestering activity under experimental conditions requiring physiological concentrations of HSA, and also of in vivo pharmacodynamic behavior. These results are likely to be useful in designing analogues with varying pharmacokinetic profiles.
Collapse
Affiliation(s)
- Thuan B Nguyen
- Department of Medicinal Chemistry, University of Kansas, Lawrence, Kansas 66047, USA
| | | | | | | | | | | | | | | |
Collapse
|
10
|
Thippakorn C, Suksrichavalit T, Nantasenamat C, Tantimongcolwat T, Isarankura-Na-Ayudhya C, Naenna T, Prachayasittikul V. Modeling the LPS neutralization activity of anti-endotoxins. Molecules 2009; 14:1869-88. [PMID: 19471207 PMCID: PMC6254205 DOI: 10.3390/molecules14051869] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2009] [Revised: 05/15/2009] [Accepted: 05/19/2009] [Indexed: 11/23/2022] Open
Abstract
Bacterial lipopolysaccharides (LPS), also known as endotoxins, are major structural components of the outer membrane of Gram-negative bacteria that serve as a barrier and protective shield between them and their surrounding environment. LPS is considered to be a major virulence factor as it strongly stimulates the secretion of pro-inflammatory cytokines which mediate the host immune response and culminating in septic shock. Quantitative structure-activity relationship studies of the LPS neutralization activities of anti-endotoxins were performed using charge and quantum chemical descriptors. Artificial neural network implementing the back-propagation algorithm was selected for the multivariate analysis. The predicted activities from leave-one-out cross-validation were well correlated with the experimental values as observed from the correlation coefficient and root mean square error of 0.930 and 0.162, respectively. Similarly, the external testing set also yielded good predictivity with correlation coefficient and root mean square error of 0.983 and 0.130. The model holds great potential for the rational design of novel and robust compounds with enhanced neutralization activity.
Collapse
Affiliation(s)
- Chadinee Thippakorn
- Department of Clinical Microbiology, Faculty of Medical Technology, Mahidol University, Bangkok, Thailand
| | | | | | | | | | | | | |
Collapse
|
11
|
Feltham HL, Brooker S. Ligands and polymetallic complexes derived from 1,4-diformyl-2,3-dihydroxybenzene and two close analogues. Coord Chem Rev 2009. [DOI: 10.1016/j.ccr.2008.10.017] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
12
|
Structure-activity relationships of lipopolysaccharide sequestration in N-alkylpolyamines. Bioorg Med Chem Lett 2009; 19:2478-81. [PMID: 19332373 DOI: 10.1016/j.bmcl.2009.03.055] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2009] [Revised: 03/10/2009] [Accepted: 03/12/2009] [Indexed: 11/23/2022]
Abstract
We have previously shown that simple N-acyl or N-alkyl polyamines bind to and sequester Gram-negative bacterial lipopolysaccharide, affording protection against lethality in animal models of endotoxicosis. Several iterative design-and-test cycles of SAR studies, including high-throughput screens, had converged on compounds with polyamine scaffolds which have been investigated extensively with reference to the number, position, and length of acyl or alkyl appendages. However, the polyamine backbone itself had not been explored sufficiently, and it was not known if incremental variations on the polymethylene spacing would affect LPS-binding and neutralization properties. We have now systematically explored the relationship between variously elongated spermidine [NH(2)-(CH(2))(3)-NH-(CH(2))(4)-NH(2)] and norspermidine [NH(2)-(CH(2))(3)-NH-(CH(2))(3)-NH(2)] backbones, with the N-alkyl group being held constant at C(16) in order to examine if changing the spacing between the inner secondary amines may yield additional SAR information. We find that the norspermine-type compounds consistently showed higher activity compared to corresponding spermine homologues.
Collapse
|
13
|
Wu W, Sil D, Szostak ML, Malladi SS, Warshakoon HJ, Kimbrell MR, Cromer JR, David SA. Structure-activity relationships of lipopolysaccharide sequestration in guanylhydrazone-bearing lipopolyamines. Bioorg Med Chem 2009; 17:709-15. [PMID: 19064323 PMCID: PMC3702171 DOI: 10.1016/j.bmc.2008.11.051] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2008] [Revised: 11/15/2008] [Accepted: 11/18/2008] [Indexed: 11/17/2022]
Abstract
The toxicity of gram-negative bacterial endotoxin (lipopolysaccharide, LPS) resides in its structurally highly conserved glycolipid component called lipid A. Our major goal has been to develop small-molecules that would sequester LPS by binding to the lipid A moiety, so that it could be useful for the prophylaxis or adjunctive therapy of gram-negative sepsis. We had previously identified in rapid-throughput screens several guanylhydrazones as potent LPS binders. We were desirous of examining if the presence of the guanylhydrazone (rather than an amine) functionality would afford greater LPS sequestration potency. In evaluating a congeneric set of guanylhydrazone analogues, we find that C(16) alkyl substitution is optimal in the N-alkylguanylhydrazone series; a homospermine analogue with the terminal amine N-alkylated with a C(16) chain with the other terminus of the molecule bearing an unsubstituted guanylhydrazone moiety is marginally more active, suggesting very slight, if any, steric effects. Neither C(16) analogue is significantly more active than the N-C(16)-alkyl or N-C(16)-acyl compounds that we had characterized earlier, indicating that basicity of the phosphate-recognizing cationic group, is not a determinant of LPS sequestration activity.
Collapse
Affiliation(s)
- Wenyan Wu
- Department of Medicinal Chemistry, University of Kansas, Lawrence, KS 66045
| | - Diptesh Sil
- Department of Medicinal Chemistry, University of Kansas, Lawrence, KS 66045
| | - Michal L. Szostak
- Department of Medicinal Chemistry, University of Kansas, Lawrence, KS 66045
| | | | | | | | - Jens R. Cromer
- Department of Medicinal Chemistry, University of Kansas, Lawrence, KS 66045
| | - Sunil A. David
- Department of Medicinal Chemistry, University of Kansas, Lawrence, KS 66045
| |
Collapse
|
14
|
Zorko M, Jerala R. Alexidine and chlorhexidine bind to lipopolysaccharide and lipoteichoic acid and prevent cell activation by antibiotics. J Antimicrob Chemother 2008; 62:730-7. [PMID: 18635521 DOI: 10.1093/jac/dkn270] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVES Many antibiotics used to treat infections cause release of immunostimulatory cell wall components from bacteria. Therefore, a combination of antimicrobial and endotoxin-neutralizing activity is desired to prevent inflammation induced by destroyed bacteria. Chlorhexidine and alexidine are amphipathic bisbiguanides and could neutralize bacterial membrane components as stimulators of Toll-like receptors (TLRs). METHODS Binding of chlorhexidine and alexidine to lipopolysaccharide (LPS) and lipoteichoic acid (LTA) was determined by fluorescence displacement assay and isothermal calorimetric titration. Neutralization of the biological effect of LPS and LTA on TLR-activated cellular activation was determined by NF-kappaB reporter luciferase activation on cells transfected with specific TLRs and NO production of murine macrophages in the presence of isolated agonists and antibiotic-treated bacteria. RESULTS Alexidine and chlorhexidine bind not only to LPS but also to LTA from Gram-positive bacteria. Alexidine has a higher affinity than chlorhexidine for both compounds. Calorimetric titration shows an initial endothermic contribution indicating participation of hydrophobic interactions in LPS binding, while binding to LTA displayed initial exothermic contribution. Both compounds prevent cell activation of TLR4 and TLR2 by LPS and LTA, respectively. The addition of both compounds suppressed NO production by macrophages in the presence of bacteria treated with different types of antibiotics. CONCLUSIONS Chlorhexidine and alexidine suppress bacterial membrane-induced cell activation at concentrations two orders of magnitude lower than that used in topical applications. Combining biocides with different types of antibiotics prevented macrophage activation in the presence of bacteria and demonstrated the potential of chlorhexidine and alexidine to suppress inflammatory responses caused by activation of TLRs.
Collapse
Affiliation(s)
- Mateja Zorko
- Department of Biotechnology, National Institute of Chemistry, Hajdrihova 19, Ljubljana, Slovenia
| | | |
Collapse
|
15
|
Johnson BJ, Delehanty JB, Lin B, Ligler FS. Immobilized proanthocyanidins for the capture of bacterial lipopolysaccharides. Anal Chem 2008; 80:2113-7. [PMID: 18257561 DOI: 10.1021/ac7024128] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Proanthocyanidins (PACs) are an abundant class of compounds found in a variety of plant materials. Here we demonstrate the application of these materials as capture molecules for the removal of bacterial lipopolysaccharide (LPS) from solution. PACs from whole cranberries, grape juice, black tea, and cranberry juice were purified and immobilized onto thiol-activated Sepharose beads. This material was used in pull-down type assays for the capture of LPS. The binding of LPS by PACs has been shown to compete with that of polymyxin B which is known to bind the lipid A component of LPS. Assays conducted in the presence of lipid A verified that at least some component of the LPS binding activity of the PACs is via the lipid A moiety. Molar comparison of polymyxin B to proanthocyanidins indicated that the Sepharose immobilized PACs have a binding affinity for LPS similar to that of polymyxin B.
Collapse
Affiliation(s)
- Brandy J Johnson
- Center for Bio/Molecular Science & Engineering, Naval Research Laboratory, Washington, D.C. 20375-5348, USA.
| | | | | | | |
Collapse
|
16
|
Zhan W, Liang Z, Zhu A, Kurtkaya S, Shim H, Snyder JP, Liotta DC. Discovery of small molecule CXCR4 antagonists. J Med Chem 2007; 50:5655-64. [PMID: 17958344 DOI: 10.1021/jm070679i] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In light of a proposed molecular mechanism for the C-X-C chemokine receptor type 4 (CXCR4) antagonist 1 (AMD3100), a template with the general structure 2 was designed, and 15 was identified as a lead by means of an affinity binding assay against the ligand-mimicking CXCR4 antagonist 3 (TN14003). Following a structure-activity profile around 15, the design and synthesis of a series of novel small molecular CXCR4 antagonists led to the discovery of 32 (WZ811). The compound shows subnanomolar potency (EC50 = 0.3 nM) in an affinity binding assay. In addition, when subjected to in vitro functional evaluation, 32 efficiently inhibits CXCR4/stromal cell-derived factor-1 (SDF-1)-mediated modulation of cyclic adenosine monophophate (cAMP) levels (EC50 = 1.2 nM) and SDF-1 induced Matrigel invasion (EC50 = 5.2 nM). Molecular field topology analysis (MFTA), a 2D quantitative structure-activity relationship (QSAR) approach based on local molecular properties (Van der Waals radii (VdW), atomic charges, and local lipophilicity), applied to the 32 series suggests structural modifications to improve potency.
Collapse
Affiliation(s)
- Weiqiang Zhan
- Department of Chemistry, Winship Cancer Institute, Emory University, Atlanta, GA 30322, USA
| | | | | | | | | | | | | |
Collapse
|
17
|
Nguyen TB, Adisechan AK, Suresh Kumar EVK, Balakrishna R, Kimbrell MR, Miller KA, Datta A, David SA. Protection from endotoxic shock by EVK-203, a novel alkylpolyamine sequestrant of lipopolysaccharide. Bioorg Med Chem 2007; 15:5694-709. [PMID: 17583517 PMCID: PMC2039869 DOI: 10.1016/j.bmc.2007.06.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2007] [Revised: 06/01/2007] [Accepted: 06/05/2007] [Indexed: 11/20/2022]
Abstract
Lipopolysaccharides (LPS) play a key role in the pathogenesis of septic shock, a major cause of mortality in the critically ill patient. The only therapeutic option aimed at limiting downstream systemic inflammatory processes by targeting lipopolysaccharide is Toraymyxin, an extracorporeal hemoperfusion device using solid phase-immobilized polymyxin B (PMB). While PMB is known to effectively sequester LPS, its severe systemic toxicity proscribes its parenteral use, and hemoperfusion may not be feasible in patients in shock. In our continuing efforts to develop small-molecule mimics which display the LPS-sequestering properties, but not the toxicity of PMB, a series of mono- and bis-substituted dialkylpolyamines were synthesized and evaluated. We show that EVK-203, an alkylpolyamine compound, specifically binds to and neutralizes the activity of LPS, and affords complete protection in a murine model of endotoxic shock. EVK-203 is without any apparent toxicity when administered to mice at multiples of therapeutic doses for several days. The specific endotoxin-sequestering property along with a very favorable therapeutic index renders this compound an ideal candidate for preclinical development.
Collapse
Affiliation(s)
- Thuan B Nguyen
- Department of Medicinal Chemistry, University of Kansas, Multidisciplinary Research Building, Lawrence, KS 66047, USA
| | | | | | | | | | | | | | | |
Collapse
|
18
|
Sil D, Shrestha A, Kimbrell MR, Nguyen TB, Adisechan AK, Balakrishna R, Abbo BG, Malladi S, Miller KA, Short S, Cromer JR, Arora S, Datta A, David SA. Bound to shock: protection from lethal endotoxemic shock by a novel, nontoxic, alkylpolyamine lipopolysaccharide sequestrant. Antimicrob Agents Chemother 2007; 51:2811-9. [PMID: 17548488 PMCID: PMC1932507 DOI: 10.1128/aac.00200-07] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Lipopolysaccharide (LPS), or endotoxin, a structural component of gram-negative bacterial outer membranes, plays a key role in the pathogenesis of septic shock, a syndrome of severe systemic inflammation which leads to multiple-system organ failure. Despite advances in antimicrobial chemotherapy, sepsis continues to be the commonest cause of death in the critically ill patient. This is attributable to the lack of therapeutic options that aim at limiting the exposure to the toxin and the prevention of subsequent downstream inflammatory processes. Polymyxin B (PMB), a peptide antibiotic, is a prototype small molecule that binds and neutralizes LPS toxicity. However, the antibiotic is too toxic for systemic use as an LPS sequestrant. Based on a nuclear magnetic resonance-derived model of polymyxin B-LPS complex, we had earlier identified the pharmacophore necessary for optimal recognition and neutralization of the toxin. Iterative cycles of pharmacophore-based ligand design and evaluation have yielded a synthetically easily accessible N(1),mono-alkyl-mono-homologated spermine derivative, DS-96. We have found that DS-96 binds LPS and neutralizes its toxicity with a potency indistinguishable from that of PMB in a wide range of in vitro assays, affords complete protection in a murine model of LPS-induced lethality, and is apparently nontoxic in vertebrate animal models.
Collapse
Affiliation(s)
- Diptesh Sil
- Department of Medicinal Chemistry, University of Kansas, Multidisciplinary Research Building, Lawrence, KS 66047, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
19
|
Hwang YH, Park BK, Lim JH, Kim MS, Park SC, Hwang MH, Yun HI. Lipopolysaccharide-binding and neutralizing activities of surfactin C in experimental models of septic shock. Eur J Pharmacol 2007; 556:166-71. [PMID: 17126323 DOI: 10.1016/j.ejphar.2006.10.031] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2006] [Revised: 10/10/2006] [Accepted: 10/11/2006] [Indexed: 11/20/2022]
Abstract
To evaluate the anti-endotoxin activity of surfactin C, we studied its lipopolysaccharide-binding activity in vitro and therapeutic efficacy in experimental models of gram-negative septic shock. The ability of surfactin C to bind LPS from Escherichia coli O111:B4 was determined using a limulus chromogenic assay. Male ICR mice and Sprague-Dawley rats were given intraperitoneal administration of 1x10(9) colony forming units of E. coli ATCC 25922. After bacterial challenge, all animals were randomized to receive intraperitoneally saline, polymyxin B or surfactin C. Surfactin C not only completely bound to the LPS (its median effective concentration being 13.75 microM) but also improved the survival and reduced of the number of inoculated bacteria in the mouse model of septic shock. Surfactin C reduced the plasma endotoxin, tumor necrosis factor-alpha and nitric oxide levels in response to septic shock in rats.
Collapse
Affiliation(s)
- Youn-Hwan Hwang
- College of Veterinary Medicine, Chungnam National University, 220 Gung-dong, Yuseong-gu, Daejeon, Korea
| | | | | | | | | | | | | |
Collapse
|
20
|
Burns MR, Jenkins SA, Kimbrell MR, Balakrishna R, Nguyen TB, Abbo BG, David SA. Polycationic Sulfonamides for the Sequestration of Endotoxin. J Med Chem 2007; 50:877-88. [PMID: 17256835 DOI: 10.1021/jm061198m] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Lipopolysaccharides (LPS) play a key role in the pathogenesis of septic shock, a major cause of mortality in the critically ill patient. We had previously shown that monoacylated polyamine compounds specifically bind to and neutralize the activity of LPS with high in vitro potency and afford complete protection in a murine model of endotoxic shock. Fatty acid amides of polyamines may be rapidly cleared from systemic circulation due to their susceptibility to nonspecific serum amidases and, thus, would be predicted to have a short duration of action. In a systematic effort to increase the likelihood of better bioavailability properties together with structural modifications that may result in gains in activity, we now report structure-activity relationships pertaining to endotoxin-binding and -neutralizing activities of homologated polyamine sulfonamides.
Collapse
Affiliation(s)
- Mark R Burns
- MediQuest Therapeutics, Inc., 22322 20th Avenue SE, Bothell, Washington 98021, USA.
| | | | | | | | | | | | | |
Collapse
|
21
|
Burns MR, Jenkins SA, Vermeulen NM, Balakrishna R, Nguyen TB, Kimbrell MR, David SA. Structural correlation between lipophilicity and lipopolysaccharide-sequestering activity in spermine-sulfonamide analogs. Bioorg Med Chem Lett 2006; 16:6209-12. [PMID: 17010608 PMCID: PMC1991285 DOI: 10.1016/j.bmcl.2006.09.026] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2006] [Revised: 09/06/2006] [Accepted: 09/08/2006] [Indexed: 11/27/2022]
Abstract
Lipopolysaccharides (LPS), otherwise termed 'endotoxins', are outer-membrane constituents of Gram-negative bacteria, and play a key role in the pathogenesis of 'Septic Shock', a major cause of mortality in the critically ill patient. We had previously defined the pharmacophore necessary for small molecules to specifically bind and neutralize this complex carbohydrate. A series of aryl and aliphatic spermine-sulfonamide analogs were synthesized and tested in a series of binding and cell-based assays in order to probe the effect of lipophilicity on sequestration ability. A strong correlation was indeed found, supporting the hypothesis that endotoxin-neutralizing ability involves a lipophilic or membrane attachment event. The research discussed herein may be useful for the design of additional carbohydrate recognizing molecules and endotoxin-neutralizing drugs.
Collapse
Affiliation(s)
- Mark R Burns
- MediQuest Therapeutics, Inc., 22322 20th Ave. SE, Bothell, WA 98021, USA
| | | | | | | | | | | | | |
Collapse
|