1
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Halldorsdottir H, Lindbom L, Ebberyd A, Oldner A, Weitzberg E. The effect of heparins on plasma concentration of heparin-binding protein: a pilot study. BJA OPEN 2024; 9:100256. [PMID: 38318270 PMCID: PMC10839136 DOI: 10.1016/j.bjao.2023.100256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/17/2023] [Accepted: 12/17/2023] [Indexed: 02/07/2024]
Abstract
Background Neutrophil-derived heparin-binding protein (HBP) plays a role in the pathophysiology of impaired endothelial dysfunction during inflammation. HBP has been suggested as a predictor of organ dysfunction and disease progression in sepsis. We investigated the effects of heparins on plasma concentrations of HBP in patients undergoing surgery. Methods We studied three groups of patients receiving heparins during or after surgery. The vascular surgery group received 3000-7500 U, whereas the cardiac surgery group received 27 500-40 000 U. After major general surgery, the third group received 5000 U of low-molecular-weight heparin (LMWH) subcutaneously. Serial plasma HBP concentrations were measured after these treatments with two different methods: Axis-Shield ELISA and Joinstar FIC-Q100. In addition, plasma myeloperoxidase and syndecan-1 were measured in the cardiac surgery group. Results During vascular surgery, heparin induced a six-fold increase in HBP within 2 min, from 3.6 (2.4-5.4) to 21.4 (9.0-35.4) ng ml-1 (P<0.001). During cardiac surgery, the higher dose of heparin elevated HBP concentrations from 5.3 (2.7-6.1) to 48.7 (38.4-70.1) ng ml-1 (P<0.0001) within 3 min. Patients receiving LMWH showed an increase from a baseline of 5.7 (3.7-12.1) ng ml-1 to a peak HBP concentration of 14.8 (9.5-18.1) ng ml-1 (P<0.0001) after 3 h. Plasma concentrations of myeloperoxidase, but not syndecan-1, also responded with a rapid increase after heparin. There was a strong correlation between the two methods for HBP analysis (r=0.94). Conclusions Plasma concentrations of HBP increased rapidly and dose-dependently after heparin administration. Subcutaneous administration of LMWH increases plasma HBP, but to a lesser degree. Clinical trial registration ClinicalTrials.gov identifier: NCT04146493.
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Affiliation(s)
- Halla Halldorsdottir
- Department of Clinical Sciences, Division of Anaesthesia and Intensive Care, Karolinska Institutet, Danderyd Hospital, Danderyd, Sweden
- Department of Physiology and Pharmacology, Section of Anaesthesiology and Intensive Care, Karolinska Institutet, Stockholm, Sweden
| | - Lennart Lindbom
- Department of Physiology and Pharmacology, Section of Anaesthesiology and Intensive Care, Karolinska Institutet, Stockholm, Sweden
| | - Anette Ebberyd
- Department of Physiology and Pharmacology, Section of Anaesthesiology and Intensive Care, Karolinska Institutet, Stockholm, Sweden
| | - Anders Oldner
- Department of Physiology and Pharmacology, Section of Anaesthesiology and Intensive Care, Karolinska Institutet, Stockholm, Sweden
- Department of Perioperative Medicine and Intensive Care, Karolinska University Hospital, Stockholm, Sweden
| | - Eddie Weitzberg
- Department of Physiology and Pharmacology, Section of Anaesthesiology and Intensive Care, Karolinska Institutet, Stockholm, Sweden
- Department of Perioperative Medicine and Intensive Care, Karolinska University Hospital, Stockholm, Sweden
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2
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Najer A, Kim J, Saunders C, Che J, Baum J, Stevens MM. Enhanced Antimalarial and Antisequestration Activity of Methoxybenzenesulfonate-Modified Biopolymers and Nanoparticles for Tackling Severe Malaria. ACS Infect Dis 2024; 10:732-745. [PMID: 38271991 PMCID: PMC10862538 DOI: 10.1021/acsinfecdis.3c00564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Revised: 01/07/2024] [Accepted: 01/08/2024] [Indexed: 01/27/2024]
Abstract
Severe malaria is a life-threatening condition that is associated with a high mortality. Severe Plasmodium falciparum infections are mediated primarily by high parasitemia and binding of infected red blood cells (iRBCs) to the blood vessel endothelial layer, a process known as sequestration. Here, we show that including the 5-amino-2-methoxybenzenesulfonate (AMBS) chemical modification in soluble biopolymers (polyglutamic acid and heparin) and poly(acrylic acid)-exposing nanoparticles serves as a universal tool to introduce a potent parasite invasion inhibitory function in these materials. Importantly, the modification did not add or eliminated (for heparin) undesired anticoagulation activity. The materials protected RBCs from invasion by various parasite strains, employing both major entry pathways. Two further P. falciparum strains, which either expose ligands for chondroitin sulfate A (CSA) or intercellular adhesion molecule 1 (ICAM-1) on iRBCs, were tested in antisequestration assays due to their relevance in placental and cerebral malaria, respectively. Antisequestration activity was found to be more efficacious with nanoparticles vs gold-standard soluble biopolymers (CSA and heparin) against both strains, when tested on receptor-coated dishes. The nanoparticles also efficiently inhibited and reversed the sequestration of iRBCs on endothelial cells. First, the materials described herein have the potential to reduce the parasite burden by acting at the key multiplication stage of reinvasion. Second, the antisequestration ability could help remove iRBCs from the blood vessel endothelium, which could otherwise cause vessel obstruction, which in turn can lead to multiple organ failure in severe malaria infections. This approach represents a further step toward creation of adjunctive therapies for this devastating condition to reduce morbidity and mortality.
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Affiliation(s)
- Adrian Najer
- Department
of Materials, Department of Bioengineering, and Institute of Biomedical
Engineering, Imperial College London, London SW7 2AZ, U.K.
- Department
of Life Sciences, Imperial College London, London SW7 2AZ, U.K.
| | - Junyoung Kim
- Department
of Materials, Department of Bioengineering, and Institute of Biomedical
Engineering, Imperial College London, London SW7 2AZ, U.K.
| | - Catherine Saunders
- Department
of Materials, Department of Bioengineering, and Institute of Biomedical
Engineering, Imperial College London, London SW7 2AZ, U.K.
| | - Junyi Che
- Department
of Materials, Department of Bioengineering, and Institute of Biomedical
Engineering, Imperial College London, London SW7 2AZ, U.K.
| | - Jake Baum
- Department
of Life Sciences, Imperial College London, London SW7 2AZ, U.K.
| | - Molly M. Stevens
- Department
of Materials, Department of Bioengineering, and Institute of Biomedical
Engineering, Imperial College London, London SW7 2AZ, U.K.
- Department
of Physiology, Anatomy and Genetics, Department of Engineering Science,
and Kavli Institute for Nanoscience Discovery, University of Oxford, Oxford OX1 3QU, U.K.
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3
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Alaithan H, Kumar N, Islam MZ, Liappis AP, Nava VE. Novel Therapeutics for Malaria. Pharmaceutics 2023; 15:1800. [PMID: 37513987 PMCID: PMC10383744 DOI: 10.3390/pharmaceutics15071800] [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: 05/29/2023] [Revised: 06/21/2023] [Accepted: 06/21/2023] [Indexed: 07/30/2023] Open
Abstract
Malaria is a potentially fatal disease caused by protozoan parasites of the genus Plasmodium. It is responsible for significant morbidity and mortality in endemic countries of the tropical and subtropical world, particularly in Africa, Southeast Asia, and South America. It is estimated that 247 million malaria cases and 619,000 deaths occurred in 2021 alone. The World Health Organization's (WHO) global initiative aims to reduce the burden of disease but has been massively challenged by the emergence of parasitic strains resistant to traditional and emerging antimalarial therapy. Therefore, development of new antimalarial drugs with novel mechanisms of action that overcome resistance in a safe and efficacious manner is urgently needed. Based on the evolving understanding of the physiology of Plasmodium, identification of potential targets for drug intervention has been made in recent years, resulting in more than 10 unique potential anti-malaria drugs added to the pipeline for clinical development. This review article will focus on current therapies as well as novel targets and therapeutics against malaria.
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Affiliation(s)
- Haitham Alaithan
- Veterans Affairs Medical Center, Washington, DC 20422, USA
- Department of Medicine, George Washington University, Washington, DC 20037, USA
| | - Nirbhay Kumar
- Department of Global Health, Milken Institute of Public Health, George Washington University, Washington, DC 20037, USA
| | - Mohammad Z Islam
- Department of Pathology and Translational Pathology, Louisiana State University Health Science Center, Shreveport, LA 71103, USA
| | - Angelike P Liappis
- Veterans Affairs Medical Center, Washington, DC 20422, USA
- Department of Medicine, George Washington University, Washington, DC 20037, USA
| | - Victor E Nava
- Veterans Affairs Medical Center, Washington, DC 20422, USA
- Department of Pathology, George Washington University, Washington, DC 20037, USA
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4
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Umumararungu T, Nkuranga JB, Habarurema G, Nyandwi JB, Mukazayire MJ, Mukiza J, Muganga R, Hahirwa I, Mpenda M, Katembezi AN, Olawode EO, Kayitare E, Kayumba PC. Recent developments in antimalarial drug discovery. Bioorg Med Chem 2023; 88-89:117339. [PMID: 37236020 DOI: 10.1016/j.bmc.2023.117339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 05/12/2023] [Accepted: 05/16/2023] [Indexed: 05/28/2023]
Abstract
Although malaria remains a big burden to many countries that it threatens their socio-economic stability, particularly in the countries where malaria is endemic, there have been great efforts to eradicate this disease with both successes and failures. For example, there has been a great improvement in malaria prevention and treatment methods with a net reduction in infection and mortality rates. However, the disease remains a global threat in terms of the number of people affected because it is one of the infectious diseases that has the highest prevalence rate, especially in Africa where the deadly Plasmodium falciparum is still widely spread. Methods to fight malaria are being diversified, including the use of mosquito nets, the target candidate profiles (TCPs) and target product profiles (TPPs) of medicine for malarial venture (MMV) strategy, the search for newer and potent drugs that could reverse chloroquine resistance, and the use of adjuvants such as rosiglitazone and sevuparin. Although these adjuvants have no antiplasmodial activity, they can help to alleviate the effects which result from plasmodium invasion such as cytoadherence. The list of new antimalarial drugs under development is long, including the out of ordinary new drugs MMV048, CDRI-97/78 and INE963 from South Africa, India and Novartis, respectively.
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Affiliation(s)
- Théoneste Umumararungu
- Department of Pharmacy, School of Medicine and Pharmacy, College of Medicine and Health Sciences, University of Rwanda, Rwanda.
| | - Jean Bosco Nkuranga
- Department of Chemistry, School of Science, College of Science and Technology, University of Rwanda, Rwanda
| | - Gratien Habarurema
- Department of Chemistry, School of Science, College of Science and Technology, University of Rwanda, Rwanda
| | - Jean Baptiste Nyandwi
- Department of Pharmacy, School of Medicine and Pharmacy, College of Medicine and Health Sciences, University of Rwanda, Rwanda
| | - Marie Jeanne Mukazayire
- Department of Pharmacy, School of Medicine and Pharmacy, College of Medicine and Health Sciences, University of Rwanda, Rwanda
| | - Janvier Mukiza
- Department of Mathematical Science and Physical Education, School of Education, College of Education, University of Rwanda, Rwanda; Rwanda Food and Drugs Authority, Nyarutarama Plaza, KG 9 Avenue, Kigali, Rwanda
| | - Raymond Muganga
- Department of Pharmacy, School of Medicine and Pharmacy, College of Medicine and Health Sciences, University of Rwanda, Rwanda; Rwanda Food and Drugs Authority, Nyarutarama Plaza, KG 9 Avenue, Kigali, Rwanda
| | - Innocent Hahirwa
- Department of Pharmacy, School of Medicine and Pharmacy, College of Medicine and Health Sciences, University of Rwanda, Rwanda
| | - Matabishi Mpenda
- Department of Pharmacy, School of Medicine and Pharmacy, College of Medicine and Health Sciences, University of Rwanda, Rwanda
| | - Alain Nyirimigabo Katembezi
- Department of Pharmacy, School of Medicine and Pharmacy, College of Medicine and Health Sciences, University of Rwanda, Rwanda; Rwanda Food and Drugs Authority, Nyarutarama Plaza, KG 9 Avenue, Kigali, Rwanda
| | - Emmanuel Oladayo Olawode
- Department of Pharmaceutical Sciences, College of Pharmacy, Larkin University, 18301 N Miami Ave #1, Miami, FL 33169, USA
| | - Egide Kayitare
- Department of Pharmacy, School of Medicine and Pharmacy, College of Medicine and Health Sciences, University of Rwanda, Rwanda
| | - Pierre Claver Kayumba
- Department of Pharmacy, School of Medicine and Pharmacy, College of Medicine and Health Sciences, University of Rwanda, Rwanda
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5
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Recent approaches in the drug research and development of novel antimalarial drugs with new targets. ACTA PHARMACEUTICA (ZAGREB, CROATIA) 2023; 73:1-27. [PMID: 36692468 DOI: 10.2478/acph-2023-0001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 09/16/2022] [Indexed: 01/25/2023]
Abstract
Malaria is a serious worldwide medical issue that results in substantial annual death and morbidity. The availability of treatment alternatives is limited, and the rise of resistant parasite types has posed a significant challenge to malaria treatment. To prevent a public health disaster, novel antimalarial agents with single-dosage therapies, extensive curative capability, and new mechanisms are urgently needed. There are several approaches to developing antimalarial drugs, ranging from alterations of current drugs to the creation of new compounds with specific targeting abilities. The availability of multiple genomic techniques, as well as recent advancements in parasite biology, provides a varied collection of possible targets for the development of novel treatments. A number of promising pharmacological interference targets have been uncovered in modern times. As a result, our review concentrates on the most current scientific and technical progress in the innovation of new antimalarial medications. The protein kinases, choline transport inhibitors, dihydroorotate dehydrogenase inhibitors, isoprenoid biosynthesis inhibitors, and enzymes involved in the metabolism of lipids and replication of deoxyribonucleic acid, are among the most fascinating antimalarial target proteins presently being investigated. The new cellular targets and drugs which can inhibit malaria and their development techniques are summarised in this study.
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6
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Hogwood J, Gray E, Mulloy B. Heparin, Heparan Sulphate and Sepsis: Potential New Options for Treatment. Pharmaceuticals (Basel) 2023; 16:271. [PMID: 37259415 PMCID: PMC9959362 DOI: 10.3390/ph16020271] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 01/22/2023] [Accepted: 02/07/2023] [Indexed: 08/31/2023] Open
Abstract
Sepsis is a life-threatening hyperreaction to infection in which excessive inflammatory and immune responses cause damage to host tissues and organs. The glycosaminoglycan heparan sulphate (HS) is a major component of the cell surface glycocalyx. Cell surface HS modulates several of the mechanisms involved in sepsis such as pathogen interactions with the host cell and neutrophil recruitment and is a target for the pro-inflammatory enzyme heparanase. Heparin, a close structural relative of HS, is used in medicine as a powerful anticoagulant and antithrombotic. Many studies have shown that heparin can influence the course of sepsis-related processes as a result of its structural similarity to HS, including its strong negative charge. The anticoagulant activity of heparin, however, limits its potential in treatment of inflammatory conditions by introducing the risk of bleeding and other adverse side-effects. As the anticoagulant potency of heparin is largely determined by a single well-defined structural feature, it has been possible to develop heparin derivatives and mimetic compounds with reduced anticoagulant activity. Such heparin mimetics may have potential for use as therapeutic agents in the context of sepsis.
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Affiliation(s)
- John Hogwood
- National Institute for Biological Standards and Control, Blanche Lane, South Mimms EN6 3QG, UK
| | - Elaine Gray
- Sackler Institute of Pulmonary Pharmacology, Institute of Pharmaceutical Science, King’s College London, Stamford St., London SE1 9NH, UK
| | - Barbara Mulloy
- Sackler Institute of Pulmonary Pharmacology, Institute of Pharmaceutical Science, King’s College London, Stamford St., London SE1 9NH, UK
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7
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Burzyńska P, Jodłowska M, Zerka A, Czujkowski J, Jaśkiewicz E. Red Blood Cells Oligosaccharides as Targets for Plasmodium Invasion. Biomolecules 2022; 12:1669. [PMID: 36421683 PMCID: PMC9687201 DOI: 10.3390/biom12111669] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 11/03/2022] [Accepted: 11/08/2022] [Indexed: 04/13/2024] Open
Abstract
The key element in developing a successful malaria treatment is a good understanding of molecular mechanisms engaged in human host infection. It is assumed that oligosaccharides play a significant role in Plasmodium parasites binding to RBCs at different steps of host infection. The formation of a tight junction between EBL merozoite ligands and glycophorin receptors is the crucial interaction in ensuring merozoite entry into RBCs. It was proposed that sialic acid residues of O/N-linked glycans form clusters on a human glycophorins polypeptide chain, which facilitates the binding. Therefore, specific carbohydrate drugs have been suggested as possible malaria treatments. It was shown that the sugar moieties of N-acetylneuraminyl-N-acetate-lactosamine and 2,3-didehydro-2-deoxy-N-acetylneuraminic acid (DANA), which is its structural analog, can inhibit P. falciparum EBA-175-GPA interaction. Moreover, heparin-like molecules might be used as antimalarial drugs with some modifications to overcome their anticoagulant properties. Assuming that the principal interactions of Plasmodium merozoites and host cells are mediated by carbohydrates or glycan moieties, glycobiology-based approaches may lead to new malaria therapeutic targets.
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Affiliation(s)
| | | | | | | | - Ewa Jaśkiewicz
- Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, R. Weigla, 553-114 Wroclaw, Poland
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8
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Najer A, Blight J, Ducker CB, Gasbarri M, Brown JC, Che J, Høgset H, Saunders C, Ojansivu M, Lu Z, Lin Y, Yeow J, Rifaie-Graham O, Potter M, Tonkin R, Penders J, Doutch JJ, Georgiadou A, Barriga HMG, Holme MN, Cunnington AJ, Bugeon L, Dallman MJ, Barclay WS, Stellacci F, Baum J, Stevens MM. Potent Virustatic Polymer-Lipid Nanomimics Block Viral Entry and Inhibit Malaria Parasites In Vivo. ACS CENTRAL SCIENCE 2022; 8:1238-1257. [PMID: 36188342 PMCID: PMC9092191 DOI: 10.1021/acscentsci.1c01368] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Infectious diseases continue to pose a substantial burden on global populations, requiring innovative broad-spectrum prophylactic and treatment alternatives. Here, we have designed modular synthetic polymer nanoparticles that mimic functional components of host cell membranes, yielding multivalent nanomimics that act by directly binding to varied pathogens. Nanomimic blood circulation time was prolonged by reformulating polymer-lipid hybrids. Femtomolar concentrations of the polymer nanomimics were sufficient to inhibit herpes simplex virus type 2 (HSV-2) entry into epithelial cells, while higher doses were needed against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Given their observed virustatic mode of action, the nanomimics were also tested with malaria parasite blood-stage merozoites, which lose their invasive capacity after a few minutes. Efficient inhibition of merozoite invasion of red blood cells was demonstrated both in vitro and in vivo using a preclinical rodent malaria model. We envision these nanomimics forming an adaptable platform for developing pathogen entry inhibitors and as immunomodulators, wherein nanomimic-inhibited pathogens can be secondarily targeted to sites of immune recognition.
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Affiliation(s)
- Adrian Najer
- Department
of Materials, Department of Bioengineering, and Institute of Biomedical
Engineering, Imperial College London, London, SW7 2AZ, U.K.
- Department
of Life Sciences, Imperial College London, London, SW7 2AZ, U.K.
| | - Joshua Blight
- Department
of Life Sciences, Imperial College London, London, SW7 2AZ, U.K.
| | | | - Matteo Gasbarri
- Institute
of Materials, Ecole Polytechnique Fédérale
de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Jonathan C. Brown
- Department
of Infectious Disease, Imperial College
London, London, W2 1PG, U.K.
| | - Junyi Che
- Department
of Materials, Department of Bioengineering, and Institute of Biomedical
Engineering, Imperial College London, London, SW7 2AZ, U.K.
| | - Håkon Høgset
- Department
of Materials, Department of Bioengineering, and Institute of Biomedical
Engineering, Imperial College London, London, SW7 2AZ, U.K.
| | - Catherine Saunders
- Department
of Materials, Department of Bioengineering, and Institute of Biomedical
Engineering, Imperial College London, London, SW7 2AZ, U.K.
| | - Miina Ojansivu
- Department
of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-171 77 Stockholm, Sweden
| | - Zixuan Lu
- Department
of Materials, Department of Bioengineering, and Institute of Biomedical
Engineering, Imperial College London, London, SW7 2AZ, U.K.
| | - Yiyang Lin
- Department
of Materials, Department of Bioengineering, and Institute of Biomedical
Engineering, Imperial College London, London, SW7 2AZ, U.K.
| | - Jonathan Yeow
- Department
of Materials, Department of Bioengineering, and Institute of Biomedical
Engineering, Imperial College London, London, SW7 2AZ, U.K.
| | - Omar Rifaie-Graham
- Department
of Materials, Department of Bioengineering, and Institute of Biomedical
Engineering, Imperial College London, London, SW7 2AZ, U.K.
| | - Michael Potter
- Department
of Materials, Department of Bioengineering, and Institute of Biomedical
Engineering, Imperial College London, London, SW7 2AZ, U.K.
| | - Renée Tonkin
- Department
of Materials, Department of Bioengineering, and Institute of Biomedical
Engineering, Imperial College London, London, SW7 2AZ, U.K.
| | - Jelle Penders
- Department
of Materials, Department of Bioengineering, and Institute of Biomedical
Engineering, Imperial College London, London, SW7 2AZ, U.K.
| | - James J. Doutch
- Rutherford
Appleton Laboratory, ISIS Neutron and Muon
Source, STFC, Didcot OX11 ODE, U.K.
| | - Athina Georgiadou
- Department
of Infectious Disease, Imperial College
London, London, W2 1PG, U.K.
| | - Hanna M. G. Barriga
- Department
of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-171 77 Stockholm, Sweden
| | - Margaret N. Holme
- Department
of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-171 77 Stockholm, Sweden
| | | | - Laurence Bugeon
- Department
of Life Sciences, Imperial College London, London, SW7 2AZ, U.K.
| | | | - Wendy S. Barclay
- Department
of Infectious Disease, Imperial College
London, London, W2 1PG, U.K.
| | - Francesco Stellacci
- Institute
of Materials, Ecole Polytechnique Fédérale
de Lausanne (EPFL), 1015 Lausanne, Switzerland
- Institute
of Bioengineering, Ecole Polytechnique Fédérale
de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Jake Baum
- Department
of Life Sciences, Imperial College London, London, SW7 2AZ, U.K.
| | - Molly M. Stevens
- Department
of Materials, Department of Bioengineering, and Institute of Biomedical
Engineering, Imperial College London, London, SW7 2AZ, U.K.
- Department
of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-171 77 Stockholm, Sweden
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9
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An update on cerebral malaria for therapeutic intervention. Mol Biol Rep 2022; 49:10579-10591. [PMID: 35670928 DOI: 10.1007/s11033-022-07625-5] [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: 12/01/2021] [Accepted: 05/20/2022] [Indexed: 10/18/2022]
Abstract
BACKGROUND Cerebral malaria is often pronounced as a major life-threatening neurological complication of Plasmodium falciparum infection. The complex pathogenic landscape of the parasite and the associated neurological complications are still not elucidated properly. The growing concerns of drugresistant parasite strains along with the failure of anti-malarial drugs to subdue post-recovery neuro-cognitive dysfunctions in cerebral malaria patients have called for a demand to explore novel biomarkers and therapeutic avenues. Due course of the brain infection journey of the parasite, events such as sequestration of infected RBCs, cytoadherence, inflammation, endothelial activation, and blood-brain barrier disruption are considered critical. METHODS In this review, we briefly summarize the diverse pathogenesis of the brain-invading parasite associated with loss of the blood-brain barrier integrity. In addition, we also discuss proteomics, transcriptomics, and bioinformatics strategies to identify an array of new biomarkers and drug candidates. CONCLUSION A proper understanding of the parasite biology and mechanism of barrier disruption coupled with emerging state-of-art therapeutic approaches could be helpful to tackle cerebral malaria.
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10
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Bush MA, Anstey NM, Yeo TW, Florence SM, Granger DL, Mwaikambo ED, Weinberg JB. Vascular Dysfunction in Malaria: Understanding the Role of the Endothelial Glycocalyx. Front Cell Dev Biol 2021; 9:751251. [PMID: 34858979 PMCID: PMC8631294 DOI: 10.3389/fcell.2021.751251] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Accepted: 09/27/2021] [Indexed: 01/18/2023] Open
Abstract
Malaria caused by Plasmodium falciparum results in over 400,000 deaths annually, predominantly affecting African children. In addition, non-falciparum species including vivax and knowlesi cause significant morbidity and mortality. Vascular dysfunction is a key feature in malaria pathogenesis leading to impaired blood perfusion, vascular obstruction, and tissue hypoxia. Contributing factors include adhesion of infected RBC to endothelium, endothelial activation, and reduced nitric oxide formation. Endothelial glycocalyx (eGC) protects the vasculature by maintaining vessel integrity and regulating cellular adhesion and nitric oxide signaling pathways. Breakdown of eGC is known to occur in infectious diseases such as bacterial sepsis and dengue and is associated with adverse outcomes. Emerging studies using biochemical markers and in vivo imaging suggest that eGC breakdown occurs during Plasmodium infection and is associated with markers of malaria disease severity, endothelial activation, and vascular function. In this review, we describe characteristics of eGC breakdown in malaria and discuss how these relate to vascular dysfunction and adverse outcomes. Further understanding of this process may lead to adjunctive therapy to preserve or restore damaged eGC and reduce microvascular dysfunction and the morbidity/mortality of malaria.
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Affiliation(s)
- Margaret A Bush
- Duke University School of Nursing and Durham VA Medical Centers, Durham, NC, United States
| | - Nicholas M Anstey
- Menzies School of Health Research, Charles Darwin University, Darwin, NT, Australia
| | - Tsin W Yeo
- Menzies School of Health Research, Charles Darwin University, Darwin, NT, Australia.,Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore.,National Centre for Infectious Diseases, Tan Tock Seng Hospital, Singapore, Singapore
| | | | - Donald L Granger
- School of Medicine, University of Utah and Salt Lake City VA Medical Centers, Salt Lake City, UT, United States
| | | | - J Brice Weinberg
- Duke University School of Medicine and Durham VA Medical Centers, Durham, NC, United States
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11
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Fernandes VDS, da Rosa R, Zimmermann LA, Rogério KR, Kümmerle AE, Bernardes LSC, Graebin CS. Antiprotozoal agents: How have they changed over a decade? Arch Pharm (Weinheim) 2021; 355:e2100338. [PMID: 34661935 DOI: 10.1002/ardp.202100338] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Revised: 09/29/2021] [Accepted: 09/30/2021] [Indexed: 12/21/2022]
Abstract
Neglected tropical diseases are a diverse group of communicable diseases that are endemic in low- or low-to-middle-income countries located in tropical and subtropical zones. The number and availability of drugs for treating these diseases are low, the administration route is inconvenient in some cases, and most of them have safety, efficacy, or adverse/toxic reaction issues. The need for developing new drugs to deal with these issues is clear, but one of the most drastic consequences of this negligence is the lack of interest in the research and development of new therapeutic options among major pharmaceutical companies. Positive changes have been achieved over the last few years, although the overall situation remains alarming. After more than one decade since the original work reviewing antiprotozoal agents came to light, now it is time to question ourselves: How has the scenario for the treatment of protozoal diseases such as malaria, leishmaniasis, human African trypanosomiasis, and American trypanosomiasis changed? This review covers the last decade in terms of the drugs currently available for the treatment of these diseases as well as the clinical candidates being currently investigated.
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Affiliation(s)
- Vitória de Souza Fernandes
- Department of Pharmaceutical Sciences, Pharmaceutical and Medicinal Chemistry Laboratory, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil
| | - Rafael da Rosa
- Department of Organic Chemistry, Medicinal Chemistry and Molecular Diversity Laboratory, Federal Rural University of Rio de Janeiro, Seropédica, Rio de Janeiro, Brazil
| | - Lara A Zimmermann
- Department of Organic Chemistry, Medicinal Chemistry and Molecular Diversity Laboratory, Federal Rural University of Rio de Janeiro, Seropédica, Rio de Janeiro, Brazil
| | - Kamilla R Rogério
- Department of Pharmaceutical Sciences, Pharmaceutical and Medicinal Chemistry Laboratory, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil
| | - Arthur E Kümmerle
- Department of Pharmaceutical Sciences, Pharmaceutical and Medicinal Chemistry Laboratory, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil
| | - Lilian S C Bernardes
- Department of Organic Chemistry, Medicinal Chemistry and Molecular Diversity Laboratory, Federal Rural University of Rio de Janeiro, Seropédica, Rio de Janeiro, Brazil
| | - Cedric S Graebin
- Department of Pharmaceutical Sciences, Pharmaceutical and Medicinal Chemistry Laboratory, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil
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12
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Bush MA, Florence SM, Yeo TW, Kalingonji AR, Chen Y, Granger DL, Rubach MP, Anstey NM, Mwaikambo ED, Weinberg JB. Degradation of endothelial glycocalyx in Tanzanian children with falciparum malaria. FASEB J 2021; 35:e21805. [PMID: 34403544 DOI: 10.1096/fj.202100277rr] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2021] [Revised: 06/25/2021] [Accepted: 07/01/2021] [Indexed: 01/20/2023]
Abstract
A layer of glycocalyx covers the vascular endothelium serving important protective and homeostatic functions. The objective of this study was to determine if breakdown of the endothelial glycocalyx (eGC) occurs during malaria infection in children. Measures of eGC integrity, endothelial activation, and microvascular reactivity were prospectively evaluated in 146 children: 44 with moderately severe malaria (MSM), 42 with severe malaria (SM), and 60 healthy controls (HC). Biochemical measures of eGC integrity included plasma syndecan-1 and total urinary glycosaminoglycans (GAG). Side-stream dark field imaging was used to quantitatively assess integrity of eGC. Plasma angiopoietin-2 (Ang-2) was measured as a marker of endothelial activation and also as a possible mediator of eGC breakdown. Our results show that urinary GAG, syndecan-1, and Ang-2 were elevated in patients with MSM and SM compared with HC. Syndecan-1 and GAG levels correlated significantly with each other and with plasma Ang-2. The eGC breakdown products also inversely correlated significantly with hemoglobin and platelet count. In the MSM group, imaging results provided further evidence for eGC degradation. Although not correlated with markers of eGC degradation, vascular function (assessed by non-invasive near infrared spectroscopy [NIRS]) demonstrated reduced microvascular reactivity, particularly affecting the SM group. Our findings provide further evidence for breakdown of eGC in falciparum malaria that may contribute to endothelial activation and adhesion of parasitized red blood cells, with reduced nitric oxide formation, and vascular dysfunction.
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Affiliation(s)
- Margaret A Bush
- School of Medicine, Duke University and Durham VA Medical Centers, Durham, NC, USA
| | | | - Tsin W Yeo
- Menzies School of Health Research, Charles Darwin University, Darwin, Australia.,Lee Kong Chian School of Medicine, Nanyang Technological University, Republic of Singapore.,National Centre for Infectious Diseases, Tan Tock Seng Hospital, Republic of Singapore
| | | | - Youwei Chen
- School of Medicine, Duke University and Durham VA Medical Centers, Durham, NC, USA
| | - Donald L Granger
- University of Utah and VA Medical Centers, Salt Lake City, UT, USA
| | - Matthew P Rubach
- School of Medicine, Duke University and Durham VA Medical Centers, Durham, NC, USA
| | - Nicholas M Anstey
- Menzies School of Health Research, Charles Darwin University, Darwin, Australia
| | | | - Joe Brice Weinberg
- School of Medicine, Duke University and Durham VA Medical Centers, Durham, NC, USA
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13
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Tisnerat C, Dassonville-Klimpt A, Gosselet F, Sonnet P. Antimalarial drug discovery: from quinine to the most recent promising clinical drug candidates. Curr Med Chem 2021; 29:3326-3365. [PMID: 34344287 DOI: 10.2174/0929867328666210803152419] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 06/10/2021] [Accepted: 06/11/2021] [Indexed: 11/22/2022]
Abstract
Malaria is a tropical threatening disease caused by Plasmodium parasites, resulting in 409,000 deaths in 2019. The delay of mortality and morbidity has been compounded by the widespread of drug resistant parasites from Southeast Asia since two decades. The emergence of artemisinin-resistant Plasmodium in Africa, where most cases are accounted, highlights the urgent need for new medicines. In this effort, the World Health Organization and Medicines for Malaria Venture joined to define clear goals for novel therapies and characterized the target candidate profile. This ongoing search for new treatments is based on imperative labor in medicinal chemistry which is summarized here with particular attention to hit-to-lead optimizations, key properties, and modes of action of these novel antimalarial drugs. This review, after presenting the current antimalarial chemotherapy, from quinine to the latest marketed drugs, focuses in particular on recent advances of the most promising antimalarial candidates in clinical and preclinical phases.
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Affiliation(s)
- Camille Tisnerat
- AGIR UR4294, UFR de Pharmacie, Université de Picardie Jules Verne, Amiens. France
| | | | | | - Pascal Sonnet
- AGIR UR4294, UFR de Pharmacie, Université de Picardie Jules Verne, Amiens. France
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14
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Goerdeler F, Seeberger PH, Moscovitz O. Unveiling the Sugary Secrets of Plasmodium Parasites. Front Microbiol 2021; 12:712538. [PMID: 34335547 PMCID: PMC8322443 DOI: 10.3389/fmicb.2021.712538] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Accepted: 06/18/2021] [Indexed: 11/18/2022] Open
Abstract
Plasmodium parasites cause malaria disease, one of the leading global health burdens for humanity, infecting hundreds of millions of people each year. Different glycans on the parasite and the host cell surface play significant roles in both malaria pathogenesis and host defense mechanisms. So far, only small, truncated N- and O-glycans have been identified in Plasmodium species. In contrast, complex glycosylphosphatidylinositol (GPI) glycolipids are highly abundant on the parasite’s cell membrane and are essential for its survival. Moreover, the parasites express lectins that bind and exploit the host cell surface glycans for different aspects of the parasite life cycle, such as adherence, invasion, and evasion of the host immune system. In parallel, the host cell glycocalyx and lectin expression serve as the first line of defense against Plasmodium parasites and directly dictate susceptibility to Plasmodium infection. This review provides an overview of the glycobiology involved in Plasmodium-host interactions and its contribution to malaria pathogenesis. Recent findings are presented and evaluated in the context of potential therapeutic exploitation.
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Affiliation(s)
- Felix Goerdeler
- Department of Biomolecular Systems, Max Planck Institute of Colloids and Interfaces, Potsdam, Germany.,Institute of Chemistry and Biochemistry, Freie Universität Berlin, Berlin, Germany
| | - Peter H Seeberger
- Department of Biomolecular Systems, Max Planck Institute of Colloids and Interfaces, Potsdam, Germany.,Institute of Chemistry and Biochemistry, Freie Universität Berlin, Berlin, Germany
| | - Oren Moscovitz
- Department of Biomolecular Systems, Max Planck Institute of Colloids and Interfaces, Potsdam, Germany
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15
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Parasite histones are toxic to brain endothelium and link blood barrier breakdown and thrombosis in cerebral malaria. Blood Adv 2021; 4:2851-2864. [PMID: 32579667 DOI: 10.1182/bloodadvances.2019001258] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Accepted: 05/17/2020] [Indexed: 12/16/2022] Open
Abstract
Microvascular thrombosis and blood-brain barrier (BBB) breakdown are key components of cerebral malaria (CM) pathogenesis in African children and are implicated in fatal brain swelling. How Plasmodium falciparum infection causes this endothelial disruption and why this occurs, particularly in the brain, is not fully understood. In this study, we have demonstrated that circulating extracellular histones, equally of host and parasite origin, are significantly elevated in CM patients. Higher histone levels are associated with brain swelling on magnetic resonance imaging. On postmortem brain sections of CM patients, we found that histones are colocalized with P falciparum-infected erythrocytes sequestered inside small blood vessels, suggesting that histones might be expelled locally during parasite schizont rupture. Histone staining on the luminal vascular surface colocalized with thrombosis and leakage, indicating a possible link between endothelial surface accumulation of histones and coagulation activation and BBB breakdown. Supporting this, patient sera or purified P falciparum histones caused disruption of barrier function and were toxic to cultured human brain endothelial cells, which were abrogated with antihistone antibody and nonanticoagulant heparin. Overall, our data support a role for histones of parasite and host origin in thrombosis, BBB breakdown, and brain swelling in CM, processes implicated in the causal pathway to death. Neutralizing histones with agents such as nonanticoagulant heparin warrant exploration to prevent brain swelling in the development or progression of CM and thereby to improve outcomes.
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16
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Abstract
Lactic acidosis and hyperlactatemia are common metabolic disturbances in patients with severe malaria. Lactic acidosis causes physiological adverse effects, which can aggravate the outcome of malaria. Despite its clear association with mortality in malaria patients, the etiology of lactic acidosis is not completely understood. In this review, the possible contributors to lactic acidosis and hyperlactatemia in patients with malaria are discussed. Both increased lactate production and impaired lactate clearance may play a role in the pathogenesis of lactic acidosis. The increased lactate production is caused by several factors, including the metabolism of intraerythrocytic Plasmodium parasites, aerobic glycolysis by activated immune cells, and an increase in anaerobic glycolysis in hypoxic cells and tissues as a consequence of parasite sequestration and anemia. Impaired hepatic and renal lactate clearance, caused by underlying liver and kidney disease, might further aggravate hyperlactatemia. Multiple factors thus participate in the etiology of lactic acidosis in malaria, and further investigations are required to fully understand their relative contributions and the consequences of this major metabolic disturbance.
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Affiliation(s)
- Hendrik Possemiers
- Laboratory of Immunoparasitology, Department of Microbiology and Immunology, Rega Institute for Medical Research, KU Leuven, University of Leuven, Belgium
| | - Leen Vandermosten
- Laboratory of Immunoparasitology, Department of Microbiology and Immunology, Rega Institute for Medical Research, KU Leuven, University of Leuven, Belgium
| | - Philippe E. Van den Steen
- Laboratory of Immunoparasitology, Department of Microbiology and Immunology, Rega Institute for Medical Research, KU Leuven, University of Leuven, Belgium
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17
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Repurposing Heparin as Antimalarial: Evaluation of Multiple Modifications Toward In Vivo Application. Pharmaceutics 2020; 12:pharmaceutics12090825. [PMID: 32872434 PMCID: PMC7557421 DOI: 10.3390/pharmaceutics12090825] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 08/06/2020] [Accepted: 08/07/2020] [Indexed: 11/16/2022] Open
Abstract
Heparin is a promising antimalarial drug due to its activity in inhibiting Plasmodium invasion of red blood cells and to the lack of resistance evolution by the parasite against it, but its potent anticoagulant activity is preventing the advance of heparin along the clinical pipeline. We have determined, in in vitro Plasmodium falciparum cultures, the antimalarial activity of heparin-derived structures of different origins and sizes, to obtain formulations having a good balance of in vitro safety (neither cytotoxic nor hemolytic), low anticoagulant activity (≤23 IU/mL according to activated partial thromboplastin time assays), and not too low antimalarial activity (IC50 at least around 100 µg/mL). This led to the selection of five chemically modified heparins according to the parameters explored, i.e., chain length, sulfation degree and position, and glycol-split, and whose in vivo toxicity indicated their safety for mice up to an intravenous dose of 320 mg/kg. The in vivo antimalarial activity of the selected formulations was poor as a consequence of their short blood half-life. The covalent crosslinking of heparin onto the surface of polyethylene glycol-containing liposomes did not affect its antimalarial activity in vitro and provided higher initial plasma concentrations, although it did not increase mean circulation time. Finding a suitable nanocarrier to impart long blood residence times to the modified heparins described here will be the next step toward new heparin-based antimalarial strategies.
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18
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Storm J, Wu Y, Davies J, Moxon CA, Craig AG. Testing the effect of PAR1 inhibitors on Plasmodium falciparum-induced loss of endothelial cell barrier function. Wellcome Open Res 2020; 5:34. [PMID: 32724861 PMCID: PMC7364184 DOI: 10.12688/wellcomeopenres.15602.3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/06/2020] [Indexed: 12/29/2022] Open
Abstract
Background: Sequestration and cytoadherence of Plasmodium falciparum-infected erythrocytes (IE) to microvascular endothelium alters endothelial barrier function and plays a role in the pathogenesis of severe malaria. Binding of IE is mediated by P. falciparum erythrocyte membrane protein 1 (PfEMP1) and the PfEMP1 variants that binds to endothelial protein C receptor (EPCR) have, in particular, been associated with the dysregulation of the coagulation/inflammation pathways in endothelial cells. This has prompted speculation about the role of protease-activated receptor-1 (PAR1) activation and signalling in causing endothelial activation and loss of barrier function in cerebral malaria. Methods: We used a co-culture of primary human brain microvascular endothelial cells (HBMEC) with P. falciparum material, recombinant PfEMP1 or lysates from IE, and measured barrier function by trans endothelial electrical resistance (TEER). A selection of PAR1 inhibitors was tested for their ability to reverse the P. falciparum and thrombin induced decrease in barrier function. Results: An initial screen in the presence of recombinant PfEMP1 identified a few inhibitors that were able to reduce the rapid thrombin-induced barrier disruption even when activated protein C (aPC) was unable to do so. However, PAR1 inhibitors did not rescue the barrier dysfunction after co-culture with IE lysate. Conclusions: The selected PAR1 inhibitors were able to reverse the disruption of barrier function by thrombin but did not reverse the IE lysate induced disruption of barrier function, implicating a different PAR1-independent mechanism. These findings have implications for the design of adjunct therapies to reduce brain swelling in cerebral malaria.
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Affiliation(s)
- Janet Storm
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
| | - Yang Wu
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
| | - Jill Davies
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
| | - Christopher A. Moxon
- Wellcome Centre for Integrative Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical Veterinary & Life Sciences, University of Glasgow, Glasgow, G12 8TA, UK
| | - Alister G. Craig
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
- Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
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19
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Storm J, Wu Y, Davies J, Moxon CA, Craig AG. Testing the effect of PAR1 inhibitors on Plasmodium falciparum-induced loss of endothelial cell barrier function. Wellcome Open Res 2020; 5:34. [PMID: 32724861 PMCID: PMC7364184.2 DOI: 10.12688/wellcomeopenres.15602.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/20/2020] [Indexed: 03/30/2024] Open
Abstract
Background: Sequestration and cytoadherence of Plasmodium falciparum-infected erythrocytes (IE) to microvascular endothelium alters endothelial barrier function and plays a role in the pathogenesis of severe malaria. Binding of IE is mediated by P. falciparum erythrocyte membrane protein 1 (PfEMP1) and the PfEMP1 variants that binds to endothelial protein C receptor (EPCR) have, in particular, been associated with the dysregulation of the coagulation/inflammation pathways in endothelial cells. This has prompted speculation about the role of protease-activated receptor-1 (PAR1) activation and signalling in causing endothelial activation and loss of barrier function in cerebral malaria. Methods: We used a co-culture of primary human brain microvascular endothelial cells (HBMEC) with P. falciparum material, recombinant PfEMP1 or lysates from IE, and measured barrier function by trans endothelial electrical resistance (TEER). A selection of PAR1 inhibitors was tested for their ability to reverse the P. falciparum and thrombin induced decrease in barrier function. Results: An initial screen in the presence of recombinant PfEMP1 identified a few inhibitors that were able to reduce the rapid thrombin-induced barrier disruption even when activated protein C (aPC) was unable to do so. However, PAR1 inhibitors did not rescue the barrier dysfunction after co-culture with IE lysate. Conclusions: The selected PAR1 inhibitors were able to reverse the disruption of barrier function by thrombin but did not reverse the IE lysate induced disruption of barrier function, implicating a different PAR1-independent mechanism. These findings have implications for the design of adjunct therapies to reduce brain swelling in cerebral malaria.
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Affiliation(s)
- Janet Storm
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
| | - Yang Wu
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
| | - Jill Davies
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
| | - Christopher A Moxon
- Wellcome Centre for Integrative Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical Veterinary & Life Sciences, University of Glasgow, Glasgow, G12 8TA, UK
| | - Alister G Craig
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
- Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
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20
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Andersson U, Ottestad W, Tracey KJ. Extracellular HMGB1: a therapeutic target in severe pulmonary inflammation including COVID-19? Mol Med 2020; 26:42. [PMID: 32380958 PMCID: PMC7203545 DOI: 10.1186/s10020-020-00172-4] [Citation(s) in RCA: 160] [Impact Index Per Article: 40.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Accepted: 04/23/2020] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND The 2019 novel coronavirus disease (COVID-19) causes for unresolved reasons acute respiratory distress syndrome in vulnerable individuals. There is a need to identify key pathogenic molecules in COVID-19-associated inflammation attainable to target with existing therapeutic compounds. The endogenous damage-associated molecular pattern (DAMP) molecule HMGB1 initiates inflammation via two separate pathways. Disulfide-HMGB1 triggers TLR4 receptors generating pro-inflammatory cytokine release. Extracellular HMGB1, released from dying cells or secreted by activated innate immunity cells, forms complexes with extracellular DNA, RNA and other DAMP or pathogen-associated molecular (DAMP) molecules released after lytic cell death. These complexes are endocytosed via RAGE, constitutively expressed at high levels in the lungs only, and transported to the endolysosomal system, which is disrupted by HMGB1 at high concentrations. Danger molecules thus get access to cytosolic proinflammatory receptors instigating inflammasome activation. It is conceivable that extracellular SARS-CoV-2 RNA may reach the cellular cytosol via HMGB1-assisted transfer combined with lysosome leakage. Extracellular HMGB1 generally exists in vivo bound to other molecules, including PAMPs and DAMPs. It is plausible that these complexes are specifically removed in the lungs revealed by a 40% reduction of HMGB1 plasma levels in arterial versus venous blood. Abundant pulmonary RAGE expression enables endocytosis of danger molecules to be destroyed in the lysosomes at physiological HMGB1 levels, but causing detrimental inflammasome activation at high levels. Stress induces apoptosis in pulmonary endothelial cells from females but necrosis in cells from males. CONCLUSION Based on these observations we propose extracellular HMGB1 to be considered as a therapeutic target for COVID-19.
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Affiliation(s)
- Ulf Andersson
- Department of Women’s and Children’s Health, Karolinska Institutet at Karolinska University Hospital, Tomtebodavägen 18A, 171 77 Stockholm, Sweden
| | - William Ottestad
- Air Ambulance department, Oslo University Hospital, Oslo, Norway
- Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Kevin J. Tracey
- Center for Biomedical Science and Bioelectronic Medicine, Feinstein Institutes for Medical Research, Northwell Health, 350 Community Drive, Manhasset, NY 11030 USA
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, 500 Hofstra University, Hempstead, New York, 11030 USA
- Department of Surgery, North Shore University Hospital, Northwell Health, 300 Community Drive, Manhasset, NY 11030 USA
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Storm J, Wu Y, Davies J, Moxon CA, Craig AG. Testing the effect of PAR1 inhibitors on Plasmodium falciparum-induced loss of endothelial cell barrier function. Wellcome Open Res 2020; 5:34. [PMID: 32724861 PMCID: PMC7364184 DOI: 10.12688/wellcomeopenres.15602.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/10/2020] [Indexed: 03/30/2024] Open
Abstract
Background: Sequestration and cytoadherence of Plasmodium falciparum-infected erythrocytes (IE) to microvascular endothelium alters endothelial barrier function and plays a role in the pathogenesis of severe malaria. Binding of IE is mediated by P. falciparum erythrocyte membrane protein 1 (PfEMP1) and the PfEMP1 variants that binds to endothelial protein C receptor (EPCR) have, in particular, been associated with the dysregulation of the coagulation/inflammation pathways in endothelial cells. This has prompted speculation about the role of protease-activated receptor-1 (PAR1) activation and signalling in causing endothelial activation and loss of barrier function in cerebral malaria. Methods: We used a co-culture of primary human brain microvascular endothelial cells (HBMEC) with P. falciparum material, recombinant PfEMP1 or lysates from IE, and measured barrier function by trans endothelial electrical resistance (TEER). A selection of PAR1 inhibitors was tested for their ability to reverse the P. falciparum and thrombin induced decrease in barrier function. Results: An initial screen in the presence of recombinant PfEMP1 identified a few inhibitors that were able to reduce the rapid thrombin-induced barrier disruption even when activated protein C (aPC) was unable to do so. However, in the IE lysate co-culture system we identified a mechanism that slowly reduces barrier function and which is insensitive to PAR1 inhibitors. Conclusions: The selected PAR1 inhibitors were able to reverse the disruption of barrier function by thrombin but did not reverse the IE lysate induced disruption of barrier function, implicating a different PAR1-independent mechanism. These findings have implications for the design of adjunct therapies to reduce brain swelling in cerebral malaria.
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Affiliation(s)
- Janet Storm
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
| | - Yang Wu
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
| | - Jill Davies
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
| | - Christopher A. Moxon
- Wellcome Centre for Integrative Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical Veterinary & Life Sciences, University of Glasgow, Glasgow, G12 8TA, UK
| | - Alister G. Craig
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
- Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
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22
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Old and Recent Advances in Life Cycle, Pathogenesis, Diagnosis, Prevention, and Treatment of Malaria Including Perspectives in Ethiopia. ScientificWorldJournal 2020. [DOI: 10.1155/2020/1295381] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Malaria, caused by apicomplexan parasite, is an old disease and continues to be a major public health threat in many countries. This article aims to present different aspects of malaria including causes, pathogenesis, prevention, and treatment in an articulate and comprehensive manner. Six Plasmodium species are recognized as the etiology of human malaria, of which Plasmodium falciparum is popular in East and Southern Africa. Malaria is transmitted mainly through Anopheles gambiae and Anopheles funestus, the two most effective malaria vectors in the world. Half of the world’s population is at risk for malaria infection. Globally, the morbidity and mortality rates of malaria have become decreased even though few reports in Ethiopia showed high prevalence of malaria. The malaria parasite has a complex life cycle that takes place both inside the mosquito and human beings. Generally, diagnosis of malaria is classified into clinical and parasitological diagnoses. Lack of clear understanding on the overall biology of Plasmodium has created a challenge in an effort to develop new drugs, vaccines, and preventive methods against malaria. However, three types of vaccines and a lot of novel compounds are under perclinical and clinical studies that are triggered by the occurrence of resistance among commonly used drugs and insecticides. Antiadhesion adjunctive therapies are also under investigation in the laboratory. In addition to previously known targets for diagnostic tool, vaccine and drug discovery scientists from all corner of the world are in search of new targets and chemical entities.
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23
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Vlodavsky I, Sanderson RD, Ilan N. Non-Anticoagulant Heparins as Heparanase Inhibitors. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1221:493-522. [PMID: 32274724 PMCID: PMC7142274 DOI: 10.1007/978-3-030-34521-1_20] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The chapter will review early and more recent seminal contributions to the discovery and characterization of heparanase and non-anticoagulant heparins inhibiting its peculiar enzymatic activity. Indeed, heparanase displays a unique versatility in degrading heparan sulfate chains of several proteoglycans expressed in all mammalian cells. This endo-β-D-glucuronidase is overexpressed in cancer, inflammation, diabetes, atherosclerosis, nephropathies and other pathologies. Starting from known low- or non-anticoagulant heparins, the search for heparanase inhibitors evolved focusing on structure-activity relationship studies and taking advantage of new chemical-physical analytical methods which have allowed characterization and sequencing of polysaccharide chains. New methods to screen heparanase inhibitors and to evaluate their mechanism of action and in vivo activity in experimental models prompted their development. New non-anticoagulant heparin derivatives endowed with anti-heparanase activity are reported. Some leads are under clinical evaluation in the oncology field (e.g., acute myeloid leukemia, multiple myeloma, pancreatic carcinoma) and in other pathological conditions (e.g., sickle cell disease, malaria, labor arrest).
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Affiliation(s)
- Israel Vlodavsky
- Technion Integrated Cancer Center (TICC) Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Haifa Israel
| | - Ralph D. Sanderson
- Department of Pathology, University of Alabama at Birmingham, Birmingham, AL USA
| | - Neta Ilan
- Technion Integrated Cancer Center (TICC) Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Haifa Israel
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Rosetting revisited: a critical look at the evidence for host erythrocyte receptors in Plasmodium falciparum rosetting. Parasitology 2019; 147:1-11. [PMID: 31455446 PMCID: PMC7050047 DOI: 10.1017/s0031182019001288] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Malaria remains a major cause of mortality in African children, with no adjunctive treatments currently available to ameliorate the severe clinical forms of the disease. Rosetting, the adhesion of infected erythrocytes (IEs) to uninfected erythrocytes, is a parasite phenotype strongly associated with severe malaria, and hence is a potential therapeutic target. However, the molecular mechanisms of rosetting are complex and involve multiple distinct receptor–ligand interactions, with some similarities to the diverse pathways involved in P. falciparum erythrocyte invasion. This review summarizes the current understanding of the molecular interactions that lead to rosette formation, with a particular focus on host uninfected erythrocyte receptors including the A and B blood group trisaccharides, complement receptor one, heparan sulphate, glycophorin A and glycophorin C. There is strong evidence supporting blood group A trisaccharides as rosetting receptors, but evidence for other molecules is incomplete and requires further study. It is likely that additional host erythrocyte rosetting receptors remain to be discovered. A rosette-disrupting low anti-coagulant heparin derivative is being investigated as an adjunctive therapy for severe malaria, and further research into the receptor–ligand interactions underlying rosetting may reveal additional therapeutic approaches to reduce the unacceptably high mortality rate of severe malaria.
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Burns AL, Dans MG, Balbin JM, de Koning-Ward TF, Gilson PR, Beeson JG, Boyle MJ, Wilson DW. Targeting malaria parasite invasion of red blood cells as an antimalarial strategy. FEMS Microbiol Rev 2019; 43:223-238. [PMID: 30753425 PMCID: PMC6524681 DOI: 10.1093/femsre/fuz005] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2018] [Accepted: 02/11/2019] [Indexed: 12/20/2022] Open
Abstract
Plasmodium spp. parasites that cause malaria disease remain a significant global-health burden. With the spread of parasites resistant to artemisinin combination therapies in Southeast Asia, there is a growing need to develop new antimalarials with novel targets. Invasion of the red blood cell by Plasmodium merozoites is essential for parasite survival and proliferation, thus representing an attractive target for therapeutic development. Red blood cell invasion requires a co-ordinated series of protein/protein interactions, protease cleavage events, intracellular signals, organelle release and engagement of an actin-myosin motor, which provide many potential targets for drug development. As these steps occur in the bloodstream, they are directly susceptible and exposed to drugs. A number of invasion inhibitors against a diverse range of parasite proteins involved in these different processes of invasion have been identified, with several showing potential to be optimised for improved drug-like properties. In this review, we discuss red blood cell invasion as a drug target and highlight a number of approaches for developing antimalarials with invasion inhibitory activity to use in future combination therapies.
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Affiliation(s)
- Amy L Burns
- Research Centre for Infectious Diseases, School of Biological Sciences, University of Adelaide, Adelaide, Australia 5005
| | - Madeline G Dans
- Burnet Institute, Melbourne, Victoria, Australia 3004.,Deakin University, School of Medicine, Waurn Ponds, Victoria, Australia 3216
| | - Juan M Balbin
- Research Centre for Infectious Diseases, School of Biological Sciences, University of Adelaide, Adelaide, Australia 5005
| | | | - Paul R Gilson
- Burnet Institute, Melbourne, Victoria, Australia 3004
| | - James G Beeson
- Burnet Institute, Melbourne, Victoria, Australia 3004.,Central Clinical School and Department of Microbiology, Monash University 3004.,Department of Medicine, University of Melbourne, Australia 3052
| | - Michelle J Boyle
- Burnet Institute, Melbourne, Victoria, Australia 3004.,QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia 4006
| | - Danny W Wilson
- Research Centre for Infectious Diseases, School of Biological Sciences, University of Adelaide, Adelaide, Australia 5005.,Burnet Institute, Melbourne, Victoria, Australia 3004
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The bacterial protein CNF1 as a new strategy against Plasmodium falciparum cytoadherence. PLoS One 2019; 14:e0213529. [PMID: 30845261 PMCID: PMC6405130 DOI: 10.1371/journal.pone.0213529] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Accepted: 02/22/2019] [Indexed: 11/19/2022] Open
Abstract
Plasmodium falciparum severe malaria causes more than 400,000 deaths every year. One feature of P. falciparum-parasitized erythrocytes (pRBC) leading to cerebral malaria (CM), the most dangerous form of severe malaria, is cytoadherence to endothelium and blockage of the brain microvasculature. Preventing ligand-receptor interactions involved in this process could inhibit pRBC sequestration and insurgence of severe disease whilst reversing existing cytoadherence could be a saving life adjunct therapy. Increasing evidence indicate the endothelial Rho signaling as a crucial player in malaria parasite cytoadherence. Therefore, we have used the cytotoxic necrotizing factor 1 (CNF1), an Escherichia coli protein able to modulate the activity of Cdc42, Rac, and Rho, three subfamilies of the Rho GTPases family, to study interactions between infected erythrocytes and cerebral endothelium in co-culture models. The main results are that CNF1 not only prevents cytoadherence but, more importantly, induces the detachment of pRBCs from endothelia monolayers. We first observed that CNF1 does affect neither parasite growth, nor the morphology and concentration of knobs that characterize the parasitized erythrocyte surface, as viewed by scanning electron microscopy. On the other hand, flow cytometry experiments show that cytoadherence reversion induced by CNF1 occurs in parallel with a decreased ICAM-1 receptor expression on the cell surface, suggesting the involvement of a toxin-promoted endocytic activity in such a response. Furthermore, since the endothelial barrier functionality is compromised by P. falciparum, we conducted a permeability assay on endothelial cells, revealing the CNF1 capacity to restore the brain endothelial barrier integrity. Then, using pull-down assays and inhibitory studies, we demonstrated, for the first time, that CNF1 is able not only to prevent but also to cause the parasite detachment by simultaneously activating Rho, Rac and Cdc42 in endothelial cells. All in all our findings indicate that CNF1 may represent a potential novel therapeutic strategy for preventing neurological complications of CM.
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Therapeutic strategies to target microbial protein-glycosaminoglycan interactions. Biochem Soc Trans 2018; 46:1505-1515. [PMID: 30381333 DOI: 10.1042/bst20170485] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Revised: 09/06/2018] [Accepted: 09/18/2018] [Indexed: 01/03/2023]
Abstract
Glycans are involved in a plethora of human pathologies including infectious diseases. Especially, glycosaminoglycans (GAGs), like heparan sulfate and chondroitin sulfate, have been found to be involved in different crucial stages of microbial invasion. Here, we review various therapeutic approaches, which target the interface of host GAGs and microbial proteins and discuss their limitations and challenges for drug development.
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Glennon EKK, Dankwa S, Smith JD, Kaushansky A. Opportunities for Host-targeted Therapies for Malaria. Trends Parasitol 2018; 34:843-860. [PMID: 30122551 PMCID: PMC6168423 DOI: 10.1016/j.pt.2018.07.011] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Revised: 07/20/2018] [Accepted: 07/23/2018] [Indexed: 12/19/2022]
Abstract
Despite the recent successes of artemisinin-based antimalarial drugs, many still die from severe malaria, and eradication efforts are hindered by the limited drugs currently available to target transmissible gametocyte parasites and liver-resident dormant Plasmodium vivax hypnozoites. Host-targeted therapy is a new direction for infectious disease drug development and aims to interfere with host molecules, pathways, or networks that are required for infection or that contribute to disease. Recent advances in our understanding of host pathways involved in parasite development and pathogenic mechanisms in severe malaria could facilitate the development of host-targeted interventions against Plasmodium infection and malaria disease. This review discusses new opportunities for host-targeted therapeutics for malaria and the potential to harness drug polypharmacology to simultaneously target multiple host pathways using a single drug intervention.
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Affiliation(s)
- Elizabeth K K Glennon
- Center for Infectious Disease Research, 307 Westlake Ave N Suite 500, Seattle, WA 98109, USA; Department of Global Health, University of Washington, Harris Hydraulics Laboratory, Box 357965, Seattle, WA 98195, USA; These authors made an equal contribution
| | - Selasi Dankwa
- Center for Infectious Disease Research, 307 Westlake Ave N Suite 500, Seattle, WA 98109, USA; These authors made an equal contribution
| | - Joseph D Smith
- Center for Infectious Disease Research, 307 Westlake Ave N Suite 500, Seattle, WA 98109, USA; Department of Global Health, University of Washington, Harris Hydraulics Laboratory, Box 357965, Seattle, WA 98195, USA
| | - Alexis Kaushansky
- Center for Infectious Disease Research, 307 Westlake Ave N Suite 500, Seattle, WA 98109, USA; Department of Global Health, University of Washington, Harris Hydraulics Laboratory, Box 357965, Seattle, WA 98195, USA.
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Paderi J, Prestwich GD, Panitch A, Boone T, Stuart K. Glycan Therapeutics: Resurrecting an Almost Pharma‐Forgotten Drug Class. ADVANCED THERAPEUTICS 2018. [DOI: 10.1002/adtp.201800082] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- John Paderi
- Symic Bio, Inc. 5980 Horton St. 94608 Emeryville CA USA
| | - Glenn D. Prestwich
- Symic Bio, Inc. 5980 Horton St. 94608 Emeryville CA USA
- Department of Medicinal ChemistryUniversity of Utah 84112 Salt Lake City UT USA
- Washington State University Health Sciences Spokane 99210 Spokane WA USA
| | - Alyssa Panitch
- Symic Bio, Inc. 5980 Horton St. 94608 Emeryville CA USA
- University of California 95616 Davis CA USA
| | - Tom Boone
- Symic Bio, Inc. 5980 Horton St. 94608 Emeryville CA USA
| | - Kate Stuart
- Symic Bio, Inc. 5980 Horton St. 94608 Emeryville CA USA
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Abstract
The last two decades have seen a surge in antimalarial drug development with product development partnerships taking a leading role. Resistance of Plasmodium falciparum to the artemisinin derivatives, piperaquine and mefloquine in Southeast Asia means new antimalarials are needed with some urgency. There are at least 13 agents in clinical development. Most of these are blood schizonticides for the treatment of uncomplicated falciparum malaria, under evaluation either singly or as part of two-drug combinations. Leading candidates progressing through the pipeline are artefenomel-ferroquine and lumefantrine-KAF156, both in Phase 2b. Treatment of severe malaria continues to rely on two parenteral drugs with ancient forebears: artesunate and quinine, with sevuparin being evaluated as an adjuvant therapy. Tafenoquine is under review by stringent regulatory authorities for approval as a single-dose treatment for Plasmodium vivax relapse prevention. This represents an advance over standard 14-day primaquine regimens; however, the risk of acute haemolytic anaemia in patients with glucose-6-phosphate dehydrogenase deficiency remains. For disease prevention, several of the newer agents show potential but are unlikely to be recommended for use in the main target groups of pregnant women and young children for some years. Latest predictions are that the malaria burden will continue to be high in the coming decades. This fact, coupled with the repeated loss of antimalarials to resistance, indicates that new antimalarials will be needed for years to come. Failure of the artemisinin-based combinations in Southeast Asia has stimulated a reappraisal of current approaches to combination therapy for malaria with incorporation of three or more drugs in a single treatment under consideration.
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Affiliation(s)
- Elizabeth A Ashley
- Myanmar Oxford Clinical Research Unit, Yangon, Myanmar.
- Nuffield Department of Medicine, Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK.
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MiR-150 predicts survival in patients with sepsis and inhibits LPS-induced inflammatory factors and apoptosis by targeting NF-κB1 in human umbilical vein endothelial cells. Biochem Biophys Res Commun 2018; 500:828-837. [PMID: 29689269 DOI: 10.1016/j.bbrc.2018.04.168] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Accepted: 04/20/2018] [Indexed: 12/14/2022]
Abstract
MiR-150 is involved into some pathological processes, such as tumorigenesis and autoimmune diseases. However, little is known about the involvement of miR-150 in human sepsis. In this study, plasma miR-150 level had a diagnostic and independent prognostic value in patients with sepsis, and negatively correlated with renal dysfunction and 28-day survival as well as plasma levels of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α). MiR-150 expression was also significantly decreased in human umbilical vein endothelial cells (HUVECs) and C57BL/6 mice with sepsis after lipopolysaccharides (LPS) treatment. In-vitro, miR-150 over-expression protected HUVECs from LPS-induced apoptosis and the expressions of nuclear factor-κB1 (NF-κB1), IL-6, TNF-α, intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and E-selectin. Furthermore, NF-κB1 was identified as a direct target of miR-150. Restored NF-κB1 expression antagonized the protective effects of miR-150, while suppression of NF-κB1 enhanced these protective effects. Our findings indicate miR-150 predicts survival in patients with sepsis and inhibits LPS-induced inflammatory factors and apoptosis by targeting NF-κB1 in human umbilical vein endothelial cells. Thus, miR-150 may be a useful biomarker or target in the diagnosis, prognosis and treatment of patients with sepsis.
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Varo R, Crowley VM, Sitoe A, Madrid L, Serghides L, Kain KC, Bassat Q. Adjunctive therapy for severe malaria: a review and critical appraisal. Malar J 2018; 17:47. [PMID: 29361945 PMCID: PMC5781278 DOI: 10.1186/s12936-018-2195-7] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Accepted: 01/19/2018] [Indexed: 01/22/2023] Open
Abstract
BACKGROUND Despite recent efforts and successes in reducing the malaria burden globally, this infection still accounts for an estimated 212 million clinical cases, 2 million severe malaria cases, and approximately 429,000 deaths annually. Even with the routine use of effective anti-malarial drugs, the case fatality rate for severe malaria remains unacceptably high, with cerebral malaria being one of the most life-threatening complications. Up to one-third of cerebral malaria survivors are left with long-term cognitive and neurological deficits. From a population point of view, the decrease of malaria transmission may jeopardize the development of naturally acquired immunity against the infection, leading to fewer total cases, but potentially an increase in severe cases. The pathophysiology of severe and cerebral malaria is not completely understood, but both parasite and host determinants contribute to its onset and outcomes. Adjunctive therapy, based on modulating the host response to infection, could help to improve the outcomes achieved with specific anti-malarial therapy. RESULTS AND CONCLUSIONS In the last decades, several interventions targeting different pathways have been tested. However, none of these strategies have demonstrated clear beneficial effects, and some have shown deleterious outcomes. This review aims to summarize evidence from clinical trials testing different adjunctive therapy for severe and cerebral malaria in humans. It also highlights some preclinical studies which have evaluated novel strategies and other candidate therapeutics that may be evaluated in future clinical trials.
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Affiliation(s)
- Rosauro Varo
- Centro de Investigação em Saúde de Manhiça, Rua 12, vila da Manhiça, 1929, Maputo, Mozambique.
- ISGlobal, Barcelona Institute for Global Health, Hospital Clínic, Universitat de Barcelona, Rosselló 132, 5th Floor, 08036, Barcelona, Spain.
| | - Valerie M Crowley
- S. A. Rotman Laboratories, Sandra Rotman Centre for Global Health, University Health Network-Toronto General Hospital, Toronto, Canada
| | - Antonio Sitoe
- Centro de Investigação em Saúde de Manhiça, Rua 12, vila da Manhiça, 1929, Maputo, Mozambique
| | - Lola Madrid
- Centro de Investigação em Saúde de Manhiça, Rua 12, vila da Manhiça, 1929, Maputo, Mozambique
- ISGlobal, Barcelona Institute for Global Health, Hospital Clínic, Universitat de Barcelona, Rosselló 132, 5th Floor, 08036, Barcelona, Spain
| | - Lena Serghides
- Toronto General Research Institute (TGRI), University Health Network, Toronto, Canada
- Women's College Research Institute, Women's College Hospital, Toronto, Canada
- Department of Immunology and Institute of Medical Sciences, University of Toronto, Toronto, Canada
| | - Kevin C Kain
- S. A. Rotman Laboratories, Sandra Rotman Centre for Global Health, University Health Network-Toronto General Hospital, Toronto, Canada
- Department of Medicine, University of Toronto, Toronto, ON, Canada
- Tropical Diseases Unit, Division of Infectious Diseases, Department of Medicine, UHN-Toronto General Hospital, Toronto, ON, Canada
| | - Quique Bassat
- Centro de Investigação em Saúde de Manhiça, Rua 12, vila da Manhiça, 1929, Maputo, Mozambique.
- ISGlobal, Barcelona Institute for Global Health, Hospital Clínic, Universitat de Barcelona, Rosselló 132, 5th Floor, 08036, Barcelona, Spain.
- ICREA, Pg. Lluís Companys 23, 08010, Barcelona, Spain.
- Pediatric Infectious Diseases Unit, Pediatrics Department, Hospital Sant Joan de Déu (University of Barcelona), Barcelona, Spain.
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