1
|
Abstract
Natural products have made a crucial and unique contribution to human health, and this is especially true in the case of malaria, where the natural products quinine and artemisinin and their derivatives and analogues, have saved millions of lives. The need for new drugs to treat malaria is still urgent, since the most dangerous malaria parasite, Plasmodium falciparum, has become resistant to quinine and most of its derivatives and is becoming resistant to artemisinin and its derivatives. This volume begins with a short history of malaria and follows this with a summary of its biology. It then traces the fascinating history of the discovery of quinine for malaria treatment and then describes quinine's biosynthesis, its mechanism of action, and its clinical use, concluding with a discussion of synthetic antimalarial agents based on quinine's structure. The volume then covers the discovery of artemisinin and its development as the source of the most effective current antimalarial drug, including summaries of its synthesis and biosynthesis, its mechanism of action, and its clinical use and resistance. A short discussion of other clinically used antimalarial natural products leads to a detailed treatment of other natural products with significant antiplasmodial activity, classified by compound type. Although the search for new antimalarial natural products from Nature's combinatorial library is challenging, it is very likely to yield new antimalarial drugs. The chapter thus ends by identifying over ten natural products with development potential as clinical antimalarial agents.
Collapse
Affiliation(s)
- David G I Kingston
- Department of Chemistry and the Virginia Tech Center for Drug Discovery, Virginia Tech, Blacksburg, VA, 24061, USA.
| | - Maria Belen Cassera
- Department of Biochemistry and Molecular Biology, and Center for Tropical and Emerging Global Diseases (CTEGD), University of Georgia, Athens, GA, 30602, USA
| |
Collapse
|
2
|
Kingston DGI, Cassera MB. Correction to: Antimalarial Natural Products. Prog Chem Org Nat Prod 2022; 117:C1. [PMID: 35666333 DOI: 10.1007/978-3-030-89873-1_2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Affiliation(s)
- David G I Kingston
- Department of Chemistry and the Virginia Tech Center for Drug Discovery, Virginia Tech, Blacksburg, VA, 24061, USA.
| | - Maria Belen Cassera
- Department of Biochemistry and Molecular Biology, and Center for Tropical and Emerging Global Diseases (CTEGD), University of Georgia, Athens, GA, 30602, USA
| |
Collapse
|
3
|
Valenciano AL, Fernández-Murga ML, Merino EF, Holderman NR, Butschek GJ, Shaffer KJ, Tyler PC, Cassera MB. Metabolic dependency of chorismate in Plasmodium falciparum suggests an alternative source for the ubiquinone biosynthesis precursor. Sci Rep 2019; 9:13936. [PMID: 31558748 PMCID: PMC6763611 DOI: 10.1038/s41598-019-50319-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Accepted: 09/10/2019] [Indexed: 01/17/2023] Open
Abstract
The shikimate pathway, a metabolic pathway absent in humans, is responsible for the production of chorismate, a branch point metabolite. In the malaria parasite, chorismate is postulated to be a direct precursor in the synthesis of p-aminobenzoic acid (folate biosynthesis), p-hydroxybenzoic acid (ubiquinone biosynthesis), menaquinone, and aromatic amino acids. While the potential value of the shikimate pathway as a drug target is debatable, the metabolic dependency of chorismate in P. falciparum remains unclear. Current evidence suggests that the main role of chorismate is folate biosynthesis despite ubiquinone biosynthesis being active and essential in the malaria parasite. Our goal in the present work was to expand our knowledge of the ubiquinone head group biosynthesis and its potential metabolic dependency on chorismate in P. falciparum. We systematically assessed the development of both asexual and sexual stages of P. falciparum in a defined medium in the absence of an exogenous supply of chorismate end-products and present biochemical evidence suggesting that the benzoquinone ring of ubiquinones in this parasite may be synthesized through a yet unidentified route.
Collapse
Affiliation(s)
- Ana Lisa Valenciano
- Department of Biochemistry & Molecular Biology, and Center for Tropical and Emerging Global Diseases (CTEGD), University of Georgia, Athens, Georgia, 30602, United States
| | - Maria L Fernández-Murga
- Laboratory of Experimental Pathology, Health Research Institute Hospital La Fe, Valencia, 46026, Spain
| | - Emilio F Merino
- Department of Biochemistry & Molecular Biology, and Center for Tropical and Emerging Global Diseases (CTEGD), University of Georgia, Athens, Georgia, 30602, United States
| | - Nicole R Holderman
- Department of Biochemistry & Molecular Biology, and Center for Tropical and Emerging Global Diseases (CTEGD), University of Georgia, Athens, Georgia, 30602, United States
| | - Grant J Butschek
- Department of Biochemistry & Molecular Biology, and Center for Tropical and Emerging Global Diseases (CTEGD), University of Georgia, Athens, Georgia, 30602, United States
| | - Karl J Shaffer
- The Ferrier Research Institute, Victoria University of Wellington, Lower Hutt, New Zealand
| | - Peter C Tyler
- The Ferrier Research Institute, Victoria University of Wellington, Lower Hutt, New Zealand
| | - Maria Belen Cassera
- Department of Biochemistry & Molecular Biology, and Center for Tropical and Emerging Global Diseases (CTEGD), University of Georgia, Athens, Georgia, 30602, United States.
| |
Collapse
|
4
|
Ghavami M, Merino EF, Yao ZK, Elahi R, Simpson ME, Fernández-Murga ML, Butler JH, Casasanta MA, Krai PM, Totrov MM, Slade DJ, Carlier PR, Cassera MB. Biological Studies and Target Engagement of the 2- C-Methyl-d-Erythritol 4-Phosphate Cytidylyltransferase (IspD)-Targeting Antimalarial Agent (1 R,3 S)-MMV008138 and Analogs. ACS Infect Dis 2018; 4:549-559. [PMID: 29072835 DOI: 10.1021/acsinfecdis.7b00159] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Malaria continues to be one of the deadliest diseases worldwide, and the emergence of drug resistance parasites is a constant threat. Plasmodium parasites utilize the methylerythritol phosphate (MEP) pathway to synthesize isopentenyl pyrophosphate (IPP) and dimethylallyl pyrophosphate (DMAPP), which are essential for parasite growth. Previously, we and others identified that the Malaria Box compound MMV008138 targets the apicoplast and that parasite growth inhibition by this compound can be reversed by supplementation of IPP. Further work has revealed that MMV008138 targets the enzyme 2- C-methyl-d-erythritol 4-phosphate cytidylyltransferase (IspD) in the MEP pathway, which converts MEP and cytidine triphosphate (CTP) to cytidinediphosphate methylerythritol (CDP-ME) and pyrophosphate. In this work, we sought to gain insight into the structure-activity relationships by probing the ability of MMV008138 analogs to inhibit PfIspD recombinant enzyme. Here, we report PfIspD inhibition data for fosmidomycin (FOS) and 19 previously disclosed analogs and report parasite growth and PfIspD inhibition data for 27 new analogs of MMV008138. In addition, we show that MMV008138 does not target the recently characterized human IspD, reinforcing MMV008138 as a prototype of a new class of species-selective IspD-targeting antimalarial agents.
Collapse
Affiliation(s)
- Maryam Ghavami
- Department of Chemistry and Virginia Tech Center for Drug Discovery, Virginia Tech, Hahn Hall South, 800 West Campus Drive, Blacksburg, Virginia 24061, United States
| | - Emilio F. Merino
- Department of Biochemistry and Virginia Tech Center for Drug Discovery, Virginia Tech, Engel Hall, 340 West Campus Drive, Blacksburg, Virginia 24061, United States
- Department of Biochemistry and Molecular Biology and Center for Tropical and Emerging Global Diseases (CTEGD), University of Georgia, 120 Green Street, Athens, Georgia 30602, United States
| | - Zhong-Ke Yao
- Department of Chemistry and Virginia Tech Center for Drug Discovery, Virginia Tech, Hahn Hall South, 800 West Campus Drive, Blacksburg, Virginia 24061, United States
| | - Rubayet Elahi
- Department of Biochemistry and Virginia Tech Center for Drug Discovery, Virginia Tech, Engel Hall, 340 West Campus Drive, Blacksburg, Virginia 24061, United States
| | - Morgan E. Simpson
- Department of Biochemistry and Virginia Tech Center for Drug Discovery, Virginia Tech, Engel Hall, 340 West Campus Drive, Blacksburg, Virginia 24061, United States
| | - Maria L. Fernández-Murga
- Department of Biochemistry and Virginia Tech Center for Drug Discovery, Virginia Tech, Engel Hall, 340 West Campus Drive, Blacksburg, Virginia 24061, United States
| | - Joshua H. Butler
- Department of Biochemistry and Molecular Biology and Center for Tropical and Emerging Global Diseases (CTEGD), University of Georgia, 120 Green Street, Athens, Georgia 30602, United States
| | - Michael A. Casasanta
- Department of Biochemistry and Virginia Tech Center for Drug Discovery, Virginia Tech, Engel Hall, 340 West Campus Drive, Blacksburg, Virginia 24061, United States
| | - Priscilla M. Krai
- Department of Biochemistry and Virginia Tech Center for Drug Discovery, Virginia Tech, Engel Hall, 340 West Campus Drive, Blacksburg, Virginia 24061, United States
| | - Maxim M. Totrov
- Molsoft LLC, 11199 Sorrento Valley Road, San Diego, California 92121, United States
| | - Daniel J. Slade
- Department of Biochemistry and Virginia Tech Center for Drug Discovery, Virginia Tech, Engel Hall, 340 West Campus Drive, Blacksburg, Virginia 24061, United States
| | - Paul R. Carlier
- Department of Chemistry and Virginia Tech Center for Drug Discovery, Virginia Tech, Hahn Hall South, 800 West Campus Drive, Blacksburg, Virginia 24061, United States
| | - Maria Belen Cassera
- Department of Biochemistry and Virginia Tech Center for Drug Discovery, Virginia Tech, Engel Hall, 340 West Campus Drive, Blacksburg, Virginia 24061, United States
- Department of Biochemistry and Molecular Biology and Center for Tropical and Emerging Global Diseases (CTEGD), University of Georgia, 120 Green Street, Athens, Georgia 30602, United States
| |
Collapse
|
5
|
Butler JH, Zhou B, Yue J, Cassera MB. Natural Products as a Source to Discover Novel Drug Targets in
P. falciparum. FASEB J 2018. [DOI: 10.1096/fasebj.2018.32.1_supplement.656.22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Joshua H. Butler
- Department of Biochemistry and Molecular Biology and Center for Tropical and Emerging Global DiseasesUniversity of Georgia – USA
| | - Bin Zhou
- State Key Laboratory of Drug ResearchShanghai Institute of Materia MedicaChinese Academy of Sciences, Shanghaiand University of Chinese Academy of SciencesBeijingPeople's Republic of China
| | - Jian‐Min Yue
- State Key Laboratory of Drug ResearchShanghai Institute of Materia MedicaChinese Academy of Sciences, Shanghaiand University of Chinese Academy of SciencesBeijingPeople's Republic of China
| | - Maria Belen Cassera
- Department of Biochemistry and Molecular Biology and Center for Tropical and Emerging Global DiseasesUniversity of Georgia – USA
| |
Collapse
|
6
|
Barisón MJ, Rapado LN, Merino EF, Furusho Pral EM, Mantilla BS, Marchese L, Nowicki C, Silber AM, Cassera MB. Metabolomic profiling reveals a finely tuned, starvation-induced metabolic switch in Trypanosoma cruzi epimastigotes. J Biol Chem 2017; 292:8964-8977. [PMID: 28356355 DOI: 10.1074/jbc.m117.778522] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Revised: 03/20/2017] [Indexed: 01/22/2023] Open
Abstract
Trypanosoma cruzi, the etiological agent of Chagas disease, is a protozoan parasite with a complex life cycle involving a triatomine insect and mammals. Throughout its life cycle, the T. cruzi parasite faces several alternating events of cell division and cell differentiation in which exponential and stationary growth phases play key biological roles. It is well accepted that arrest of the cell division in the epimastigote stage, both in the midgut of the triatomine insect and in vitro, is required for metacyclogenesis, and it has been previously shown that the parasites change the expression profile of several proteins when entering this quiescent stage. However, little is known about the metabolic changes that epimastigotes undergo before they develop into the metacyclic trypomastigote stage. We applied targeted metabolomics to measure the metabolic intermediates in the most relevant pathways for energy metabolism and oxidative imbalance in exponentially growing and stationary growth-arrested epimastigote parasites. We show for the first time that T. cruzi epimastigotes transitioning from the exponential to the stationary phase exhibit a finely tuned adaptive metabolic mechanism that enables switching from glucose to amino acid consumption, which is more abundant in the stationary phase. This metabolic plasticity appears to be crucial for survival of the T. cruzi parasite in the myriad different environmental conditions to which it is exposed during its life cycle.
Collapse
Affiliation(s)
- María Julia Barisón
- From the Laboratory of Biochemistry of Tryps-LaBTryps, Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, 05508-000 São Paulo, Brazil
| | - Ludmila Nakamura Rapado
- From the Laboratory of Biochemistry of Tryps-LaBTryps, Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, 05508-000 São Paulo, Brazil
| | - Emilio F Merino
- the Department of Biochemistry and Virginia Tech Center for Drug Discovery, Virginia Tech, Blacksburg, Virginia 24061, and
| | - Elizabeth Mieko Furusho Pral
- From the Laboratory of Biochemistry of Tryps-LaBTryps, Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, 05508-000 São Paulo, Brazil
| | - Brian Suarez Mantilla
- From the Laboratory of Biochemistry of Tryps-LaBTryps, Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, 05508-000 São Paulo, Brazil
| | - Letícia Marchese
- From the Laboratory of Biochemistry of Tryps-LaBTryps, Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, 05508-000 São Paulo, Brazil
| | - Cristina Nowicki
- the Facultad de Farmacia y Bioquímica, Instituto de Química y Fisicoquímica Biológica (IQUIFIB-CONICET), Universidad de Buenos Aires, 1113 Buenos Aires, Argentina
| | - Ariel Mariano Silber
- From the Laboratory of Biochemistry of Tryps-LaBTryps, Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, 05508-000 São Paulo, Brazil,
| | - Maria Belen Cassera
- the Department of Biochemistry and Virginia Tech Center for Drug Discovery, Virginia Tech, Blacksburg, Virginia 24061, and
| |
Collapse
|
7
|
Martin JL, Yates PA, Boitz JM, Koop DR, Fulwiler AL, Cassera MB, Ullman B, Carter NS. A role for adenine nucleotides in the sensing mechanism to purine starvation in Leishmania donovani. Mol Microbiol 2016; 101:299-313. [PMID: 27062185 DOI: 10.1111/mmi.13390] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/30/2016] [Indexed: 01/25/2023]
Abstract
Purine salvage by Leishmania is an obligatory nutritional process that impacts both cell viability and growth. Previously, we have demonstrated that the removal of purines in culture provokes significant metabolic changes that enable Leishmania to survive prolonged periods of purine starvation. In order to understand how Leishmania sense and respond to changes in their purine environment, we have exploited several purine pathway mutants, some in which adenine and guanine nucleotide metabolism is uncoupled. While wild type parasites grow in any one of a variety of naturally occurring purines, the proliferation of these purine pathway mutants requires specific types or combinations of exogenous purines. By culturing purine pathway mutants in high levels of extracellular purines that are either permissive or non-permissive for growth and monitoring for previously defined markers of the adaptive response to purine starvation, we determined that adaptation arises from a surveillance of intracellular purine nucleotide pools rather than from a direct sensing of the extracellular purine content of the environment. Specifically, our data suggest that perturbation of intracellular adenine-containing nucleotide pools provides a crucial signal for inducing the metabolic changes necessary for the long-term survival of Leishmania in a purine-scarce environment.
Collapse
Affiliation(s)
- Jessica L Martin
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR, 97239-3098, USA
| | - Phillip A Yates
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR, 97239-3098, USA
| | - Jan M Boitz
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR, 97239-3098, USA
| | - Dennis R Koop
- Physiology and Pharmacology, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR, 97239-3098, USA
| | - Audrey L Fulwiler
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR, 97239-3098, USA
| | - Maria Belen Cassera
- Department of Biochemistry and Virginia Tech Center for Drug Discovery, M/C 0308, Virginia, Tech, Blacksburg, VA, 24061, USA
| | - Buddy Ullman
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR, 97239-3098, USA
| | - Nicola S Carter
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR, 97239-3098, USA
| |
Collapse
|
8
|
Saito AY, Sussmann RAC, Kimura EA, Cassera MB, Katzin AM. Quantification of nerolidol in mouse plasma using gas chromatography-mass spectrometry. J Pharm Biomed Anal 2015; 111:100-3. [PMID: 25880240 DOI: 10.1016/j.jpba.2015.03.030] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Revised: 03/20/2015] [Accepted: 03/26/2015] [Indexed: 10/23/2022]
Abstract
Nerolidol is a naturally occurring sesquiterpene found in the essential oils of many types of flowers and plants. It is frequently used in cosmetics, as a food flavoring agent, and in cleaning products. In addition, nerolidol is used as a skin penetration enhancer for transdermal delivery of therapeutic drugs. However, nerolidol is hemolytic at low concentrations. A simple and fast GC-MS method was developed for preliminary quantification and assessment of biological interferences of nerolidol in mouse plasma after oral dosing. Calibration curves were linear in the concentration range of 0.010-5 μg/mL nerolidol in mouse plasma with correlation coefficients (r) greater than 0.99. Limits of detection and quantification were 0.0017 and 0.0035 μg/mL, respectively. The optimized method was successfully applied to the quantification of nerolidol in mouse plasma.
Collapse
Affiliation(s)
- Alexandre Yukio Saito
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, Av. Prof. Lineu Prestes, 1374, São Paulo, SP 05508-000, Brazil
| | - Rodrigo Antonio Ceschini Sussmann
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, Av. Prof. Lineu Prestes, 1374, São Paulo, SP 05508-000, Brazil
| | - Emilia Akemi Kimura
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, Av. Prof. Lineu Prestes, 1374, São Paulo, SP 05508-000, Brazil
| | - Maria Belen Cassera
- Department of Biochemistry and Virginia Tech Center for Drug Discovery, M/C 0308, Virginia Tech, Blacksburg, VA 24061, United States
| | - Alejandro Miguel Katzin
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, Av. Prof. Lineu Prestes, 1374, São Paulo, SP 05508-000, Brazil
| |
Collapse
|
9
|
Yao ZK, Krai PM, Merino EF, Simpson ME, Slebodnick C, Cassera MB, Carlier PR. Determination of the active stereoisomer of the MEP pathway-targeting antimalarial agent MMV008138, and initial structure-activity studies. Bioorg Med Chem Lett 2015; 25:1515-9. [PMID: 25754494 PMCID: PMC4374032 DOI: 10.1016/j.bmcl.2015.02.020] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Revised: 02/03/2015] [Accepted: 02/09/2015] [Indexed: 10/24/2022]
Abstract
Compounds that target isoprenoid biosynthesis in Plasmodium falciparum could be a welcome addition to malaria chemotherapy, since the methylerythritol phosphate (MEP) pathway used by the parasite is not present in humans. We previously reported that MMV008138 targets the apicoplast of P. falciparum and that its target in the MEP pathway differs from that of Fosmidomycin. In this Letter, we determine that the active stereoisomer of MMV008138 is 4a, which is (1R,3S)-configured. 2',4'-Disubstitution of the D ring was also found to be crucial for inhibition of the parasite growth. Limited variation of the C3-carboxylic acid substituent was carried out, and methylamide derivative 8a was found to be more potent than 4a; other amides, acylhydrazines, and esters were less potent. Finally, lead compounds 4a, 4e, 4f, 4h, 8a, and 8e did not inhibit growth of Escherichia coli, suggesting that protozoan-selective inhibition of the MEP pathway of P. falciparum can be achieved.
Collapse
Affiliation(s)
- Zhong-Ke Yao
- Department of Chemistry and Virginia Tech Center for Drug Discovery, Virginia Tech, Blacksburg, VA 24061, United States
| | - Priscilla M Krai
- Department of Biochemistry and Virginia Tech Center for Drug Discovery, Virginia Tech, Blacksburg, VA 24061, United States
| | - Emilio F Merino
- Department of Biochemistry and Virginia Tech Center for Drug Discovery, Virginia Tech, Blacksburg, VA 24061, United States
| | - Morgan E Simpson
- Department of Biochemistry and Virginia Tech Center for Drug Discovery, Virginia Tech, Blacksburg, VA 24061, United States
| | - Carla Slebodnick
- Department of Chemistry and Virginia Tech Center for Drug Discovery, Virginia Tech, Blacksburg, VA 24061, United States
| | - Maria Belen Cassera
- Department of Biochemistry and Virginia Tech Center for Drug Discovery, Virginia Tech, Blacksburg, VA 24061, United States
| | - Paul R Carlier
- Department of Chemistry and Virginia Tech Center for Drug Discovery, Virginia Tech, Blacksburg, VA 24061, United States.
| |
Collapse
|
10
|
Belen Cassera M, Zhang Y, Z. Hazleton K, L. Schramm V. Purine and Pyrimidine Pathways as Targets in Plasmodium falciparum. Curr Top Med Chem 2011; 11:2103-15. [DOI: 10.2174/156802611796575948] [Citation(s) in RCA: 98] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2010] [Accepted: 07/06/2010] [Indexed: 11/22/2022]
|
11
|
Cassera MB, Silber AM, Gennaro AM. Differential effects of cholesterol on acyl chain order in erythrocyte membranes as a function of depth from the surface. An electron paramagnetic resonance (EPR) spin label study. Biophys Chem 2002; 99:117-27. [PMID: 12377363 DOI: 10.1016/s0301-4622(02)00139-4] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The purpose of this work is to analyze the effects of cholesterol modulation on acyl chain ordering in the membrane of human erythrocytes as a function of depth from the surface. Partial cholesterol depletion was achieved by incubation of erythrocytes with liposomes containing saturated phospholipids, or with methyl-beta-cyclodextrin (MbetaCD). Cholesterol enrichment was achieved by incubation with liposomes formed by phospholipids/cholesterol, or with the complex MbetaCD/cholesterol. Acyl chain order was studied with electron paramagnetic resonance spectroscopy (EPR) using spin labels that sense the lipid bilayer at different depths. It is shown that the increase in cholesterol stiffens acyl chains but decreases the interaction among lipid headgroups, while cholesterol depletion causes the opposite behavior. It is likely that the observed cholesterol effects are related to those stabilizing the cholesterol-rich detergent-insoluble membrane domains (rafts), recently shown to exist in erythrocytes.
Collapse
Affiliation(s)
- M B Cassera
- Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional de Litoral, Paraje El Pozo S/N, 3000, Santa Fe, Argentina
| | | | | |
Collapse
|