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Tan AF, Sakam SSB, Piera K, Rajahram GS, William T, Barber BE, Anstey NM, Grigg MJ, Kho S. Neutrophil activation, acute lung injury and disease severity in Plasmodium knowlesi malaria. PLoS Negl Trop Dis 2024; 18:e0012424. [PMID: 39150978 DOI: 10.1371/journal.pntd.0012424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Revised: 08/28/2024] [Accepted: 08/02/2024] [Indexed: 08/18/2024] Open
Abstract
The risk of severe malaria from the zoonotic parasite Plasmodium knowlesi approximates that from P. falciparum. In severe falciparum malaria, neutrophil activation contributes to inflammatory pathogenesis, including acute lung injury (ALI). The role of neutrophil activation in the pathogenesis of severe knowlesi malaria has not been examined. We evaluated 213 patients with P. knowlesi mono-infection (138 non-severe, 75 severe) and 49 Plasmodium-negative controls from Malaysia. Markers of neutrophil activation (soluble neutrophil elastase [NE], citrullinated histone [CitH3] and circulating neutrophil extracellular traps [NETs]) were quantified in peripheral blood by microscopy and immunoassays. Findings were correlated with malaria severity, ALI clinical criteria, biomarkers of parasite biomass, haemolysis, and endothelial activation. Neutrophil activation increased with disease severity, with median levels higher in severe than non-severe malaria and controls for NE (380[IQR:210-930]ng/mL, 236[139-448]ng/mL, 218[134-307]ng/mL, respectively) and CitH3 (8.72[IQR:3.0-23.1]ng/mL, 4.29[1.46-9.49]ng/mL, 1.53[0.6-2.59]ng/mL, respectively)[all p<0.01]. NETs were higher in severe malaria compared to controls (126/μL[IQR:49-323] vs 51[20-75]/μL, p<0.001). In non-severe malaria, neutrophil activation fell significantly upon discharge from hospital (p<0.03). In severe disease, NETs, NE, and CitH3 were correlated with parasitaemia, cell-free haemoglobin and angiopoietin-2 (all Pearson's r>0.24, p<0.05). Plasma NE and angiopoietin-2 were higher in knowlesi patients with ALI than those without (p<0.008); neutrophilia was associated with an increased risk of ALI (aOR 3.27, p<0.01). In conclusion, neutrophil activation is increased in ALI and in proportion to disease severity in knowlesi malaria, is associated with endothelial activation, and may contribute to disease pathogenesis. Trials of adjunctive therapies to regulate neutrophil activation are warranted in severe knowlesi malaria.
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Affiliation(s)
- Angelica F Tan
- Global and Tropical Health Division, Menzies School of Health Research, Charles Darwin University, Darwin, Australia
- Infectious Diseases Society Kota Kinabalu Sabah - Menzies School of Health Research Clinical Research Unit, Kota Kinabalu, Malaysia
- QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Sitti Saimah Binti Sakam
- Infectious Diseases Society Kota Kinabalu Sabah - Menzies School of Health Research Clinical Research Unit, Kota Kinabalu, Malaysia
| | - Kim Piera
- Global and Tropical Health Division, Menzies School of Health Research, Charles Darwin University, Darwin, Australia
| | - Giri S Rajahram
- Infectious Diseases Society Kota Kinabalu Sabah - Menzies School of Health Research Clinical Research Unit, Kota Kinabalu, Malaysia
- Clinical Research Centre, Queen Elizabeth Hospital, Kota Kinabalu, Malaysia
- Queen Elizabeth Hospital II, Ministry of Health Malaysia, Kota Kinabalu, Malaysia
- School of Medicine and Health Sciences, Monash University Malaysia, Kuala Lumpur, Malaysia
| | - Timothy William
- Infectious Diseases Society Kota Kinabalu Sabah - Menzies School of Health Research Clinical Research Unit, Kota Kinabalu, Malaysia
- Clinical Research Centre, Queen Elizabeth Hospital, Kota Kinabalu, Malaysia
| | - Bridget E Barber
- Global and Tropical Health Division, Menzies School of Health Research, Charles Darwin University, Darwin, Australia
- QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Nicholas M Anstey
- Global and Tropical Health Division, Menzies School of Health Research, Charles Darwin University, Darwin, Australia
- Infectious Diseases Society Kota Kinabalu Sabah - Menzies School of Health Research Clinical Research Unit, Kota Kinabalu, Malaysia
| | - Matthew J Grigg
- Global and Tropical Health Division, Menzies School of Health Research, Charles Darwin University, Darwin, Australia
- Infectious Diseases Society Kota Kinabalu Sabah - Menzies School of Health Research Clinical Research Unit, Kota Kinabalu, Malaysia
| | - Steven Kho
- Global and Tropical Health Division, Menzies School of Health Research, Charles Darwin University, Darwin, Australia
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Identifying Targets of Protective Antibodies against Severe Malaria in Papua, Indonesia, Using Locally Expressed Domains of Plasmodium falciparum Erythrocyte Membrane Protein 1. Infect Immun 2022; 90:e0043521. [PMID: 34871039 PMCID: PMC8853675 DOI: 10.1128/iai.00435-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1), a diverse family of multidomain proteins expressed on the surface of malaria-infected erythrocytes, is an important target of protective immunity against malaria. Our group recently studied transcription of the var genes encoding PfEMP1 in individuals from Papua, Indonesia, with severe or uncomplicated malaria. We cloned and expressed domains from 32 PfEMP1s, including 22 that were upregulated in severe malaria and 10 that were upregulated in uncomplicated malaria, using a wheat germ cell-free expression system. We used Luminex technology to measure IgG antibodies to these 32 domains and control proteins in 63 individuals (11 children). At presentation to hospital, levels of antibodies to PfEMP1 domains were either higher in uncomplicated malaria or were not significantly different between groups. Using principal component analysis, antibodies to 3 of 32 domains were highly discriminatory between groups. These included two domains upregulated in severe malaria, a DBLβ13 domain and a CIDRα1.6 domain (which has been previously implicated in severe malaria pathogenesis), and a DBLδ domain that was upregulated in uncomplicated malaria. Antibody to control non-PfEMP1 antigens did not differ with disease severity. Antibodies to PfEMP1 domains differ with malaria severity. Lack of antibodies to locally expressed PfEMP1 types, including both domains previously associated with severe malaria and newly identified targets, may in part explain malaria severity in Papuan adults.
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Knowlesi malaria: Human risk factors, clinical spectrum, and pathophysiology. ADVANCES IN PARASITOLOGY 2021; 113:1-43. [PMID: 34620381 DOI: 10.1016/bs.apar.2021.08.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Plasmodium knowlesi is endemic across Southeast Asia, and is the commonest cause of zoonotic malaria. The spectrum of clinical disease from P. knowlesi infection ranges from asymptomatic infection, through to severe malaria and death. Over 90% of clinical disease occurs in adults, mostly living in forest edge areas undergoing intensive land use change. With a 24-h asexual life cycle in humans, high parasite counts are possible, but most clinical cases of knowlesi malaria are uncomplicated with low parasitaemia. In co-endemic areas, median parasitaemia in knowlesi malaria is lower than that seen in vivax and falciparum malaria, suggesting a lower fever threshold. Severe malaria occurs in 6-9% of symptomatic adults. Manifestations of severe malaria from P. knowlesi are similar to those seen with falciparum malaria, with the notable absence of coma. Age, parasitaemia, cardiovascular comorbidities and delayed diagnosis are risk factors for severe disease and death, which are only seen in adults. Thrombocytopenia is near-universal in adults, likely related to platelet-red cell binding and clearance. Mechanisms underlying the microvascular sludging seen in fatal disease in non-natural primate hosts and the microvascular accumulation of parasites in fatal human disease are not clear. Marked reductions in deformability of both infected and uninfected red blood cells are associated with disease severity in both humans and other non-natural primate hosts, likely contributing to impaired microvascular perfusion and organ dysfunction. Endothelial activation, endothelial dysfunction, glycocalyx degradation and haemolysis are also associated with, and likely contribute to, severe disease and organ dysfunction, particularly acute kidney injury.
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Olanlokun JO, Ekundayo MT, Ebenezer O, Koorbanally NA, Olorunsogo OO. Antimalarial and Erythrocyte Membrane Stability Properties of Globimetula braunii (Engle Van Tiegh) Growing on Cocoa in Plasmodium berghei-Infected Mice. Infect Drug Resist 2021; 14:3795-3808. [PMID: 34584427 PMCID: PMC8462095 DOI: 10.2147/idr.s317732] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 07/07/2021] [Indexed: 02/02/2023] Open
Abstract
Introduction Resistant malaria is a fatal disease. Globimetula braunii (African Mistletoe) is traditionally used for malarial treatment but this fact has not been scientifically reported. Methods Plasmodium berghei (NK65)-infected male Swiss mice (20±2 g) were treated orally and once daily with 100, 200, and 400 mg/kg BW of methanol extract and its respective hexane, dichloromethane and ethyl acetate fractions for 9 days. P-alaxin was used as control drug P. berghei (ANKA)-infected mice were then treated with the most potent fraction for 5 days. Parasitemia and parasite clearance were determined by microscopy, while hematological parameters, heme, hemozoin, and mouse erythrocyte membrane stabilisation were assayed. The phytochemicals in the most potent fraction were identified using gas chromatography-mass spectrometry. Results Hexane fraction (HF)-treated mice (400 mg/kg BW) had the least mean parasite load (0.00 ± 0.00; 0.14 ± 0.05%) and highest clearance (100 ± 0.00; 75.50 ± 4.95%) compared with infected control (9.81 ± 0.09; 6.84 ± 0.09%) in susceptible and resistant models, respectively. Hexane fraction modulated hematological indices, minimised erythrocyte membrane damage in heat-induced (2.18 ± 0.94%) and hypotonic solution-induced (7.93 ± 0.93%) compared to artequin (5.05 ± 2.18; 6.38 ± 0.33%) and P-alaxin (67.45 ± 5.15; 56.78 ± 1.10%) in both models of membrane stabilisation, respectively. Hexane fraction (P<0.01) increased heme and decreased hemozoin contents. Friedelan-3-one was identified as the most abundant triterpene. Conclusion The results indicated that G. braunii has anti-plasmodial properties and minimally dis-stabilised erythrocyte membrane. The major findings in this study are that n-hexane fraction of G. braunii possess excellent and moderate antiplasmodial activity against susceptible and resistant P. berghei, respectively. This was reflected via decreased parasite load, improved hematological parameters, increased heme and decreased hemozoin contents. Friedelan-3-one, a major constituent of the n-hexane fraction, may be responsible for this activity.
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Affiliation(s)
- John Oludele Olanlokun
- Laboratories for Biomembrane Research and Biotechnology, Faculty of Basic Medical Sciences, College of Medicine, University of Ibadan, Ibadan, 4000, Nigeria
| | - Mercy Toluwase Ekundayo
- Laboratories for Biomembrane Research and Biotechnology, Faculty of Basic Medical Sciences, College of Medicine, University of Ibadan, Ibadan, 4000, Nigeria
| | - Oluwakemi Ebenezer
- School of Chemistry and Physics, University of KwaZulu-Natal, Durban, 4006, South Africa
| | | | - Olufunso Olabode Olorunsogo
- Laboratories for Biomembrane Research and Biotechnology, Faculty of Basic Medical Sciences, College of Medicine, University of Ibadan, Ibadan, 4000, Nigeria
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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: 5] [Impact Index Per Article: 1.7] [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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Barber BE, Grigg MJ, Piera KA, Chen Y, William T, Weinberg JB, Yeo TW, Anstey NM. Endothelial glycocalyx degradation and disease severity in Plasmodium vivax and Plasmodium knowlesi malaria. Sci Rep 2021; 11:9741. [PMID: 33963210 PMCID: PMC8105350 DOI: 10.1038/s41598-021-88962-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Accepted: 04/13/2021] [Indexed: 02/03/2023] Open
Abstract
Degradation of the endothelial glycocalyx is associated with mortality in adult falciparum malaria. However, its role in the pathogenesis of non-falciparum malaria is unknown. In Malaysian patients with knowlesi (n = 200) and vivax (n = 61) malaria, and in healthy controls (n = 50), we measured glycocalyx breakdown products plasma syndecan-1 and urinary glycosaminoglycans, and evaluated correlations with biomarkers of disease severity. Urinary glycosaminoglycans were increased in patients with knowlesi and vivax malaria compared to healthy controls, and in knowlesi malaria were highest in those with severe disease. In knowlesi malaria, plasma syndecan-1 was also highest in those with severe disease, and correlated with markers of endothelial activation (angiopoietin-2, osteoprotegerin, ICAM-1), asymmetric dimethylarginine (ADMA) and impaired microvascular reactivity. Syndecan-1 also correlated with endothelial activation (ICAM-1, angiopoietin-2) and ADMA in vivax malaria. In knowlesi malaria increased syndecan-1 was associated with acute kidney injury, after controlling for age and parasitemia. In knowlesi malaria, the difference in median syndecan-1 between severe and non-severe disease was more marked in females than males. Endothelial glycocalyx degradation is increased in knowlesi and vivax malaria, and associated with disease severity and acute kidney injury in knowlesi malaria. Agents that inhibit glycocalyx breakdown may represent adjunctive therapeutics for severe non-falciparum malaria.
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Affiliation(s)
- Bridget E. Barber
- QIMR Berghofer Medical Research Institute, 300 Herston Rd, Herston, Brisbane, QLD 4006 Australia ,Menzies School of Health Research and Charles Darwin University, Darwin, Australia ,Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, Kota Kinabalu, Malaysia
| | - Matthew J. Grigg
- Menzies School of Health Research and Charles Darwin University, Darwin, Australia ,Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, Kota Kinabalu, Malaysia
| | - Kim A. Piera
- Menzies School of Health Research and Charles Darwin University, Darwin, Australia
| | - Youwei Chen
- Duke University and V.A. Medical Centre, Durham, USA
| | - Timothy William
- Clinical Research Centre, Queen Elizabeth Hospital, Kota Kinabalu, Malaysia ,Gleneagles Hospital, Kota Kinabalu, Malaysia
| | | | - Tsin W. Yeo
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
| | - Nicholas M. Anstey
- Menzies School of Health Research and Charles Darwin University, Darwin, Australia ,Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, Kota Kinabalu, Malaysia
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Marrelli MT, Wang Z, Huang J, Brotto M. The skeletal muscles of mice infected with Plasmodium berghei and Plasmodium chabaudi reveal a crosstalk between lipid mediators and gene expression. Malar J 2020; 19:254. [PMID: 32664933 PMCID: PMC7362477 DOI: 10.1186/s12936-020-03332-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Accepted: 07/09/2020] [Indexed: 11/21/2022] Open
Abstract
Background Malaria is one of the most prevalent infectious disease in the world with 3.2 billion humans at risk. Malaria causes splenomegaly and damage in other organs including skeletal muscles. Skeletal muscles comprise nearly 50% of the human body and are largely responsible for the regulation and modulation of overall metabolism. It is essential to understand how malaria damages muscles in order to develop effective preventive measures and/or treatments. Using a pre-clinical animal model, the potential molecular mechanisms of Plasmodium infection affecting skeletal muscles of mice were investigated. Methods Mouse Signal Transduction Pathway Finder PCR Array was used to monitor gene expression changes of 10 essential signalling pathways in skeletal muscles from mice infected with Plasmodium berghei and Plasmodium chabaudi. Then, a new targeted-lipidomic approach using liquid chromatography with tandem mass spectrometry (LC–MS/MS) to profile 158 lipid signalling mediators (LMs), mostly eicosanoids derived from arachidonic acid (AA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), was applied. Finally, 16 key LMs directly associated with inflammation, oxidative stress, and tissue healing in skeletal muscles, were quantified. Results The results showed that the expression of key genes altered by Plasmodium infection is associated with inflammation, oxidative stress, and atrophy. In support to gene profiling results, lipidomics revealed higher concentrations of LMs in skeletal muscles directly related to inflammatory responses, while on the levels of LMs crucial in resolving inflammation and tissue repair reduced significantly. Conclusion The results provide new insights into the molecular mechanisms of malaria-induced muscle damage and revealed a potential mechanism modulating inflammation in malarial muscles. These pre-clinical studies should help with future clinical studies in humans aimed at monitoring of disease progression and development of specific interventions for the prevention and mitigation of long-term chronic effects on skeletal muscle function.
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Affiliation(s)
- Mauro Toledo Marrelli
- Department of Epidemiology, School of Public Health, University of São Paulo, Avenida Dr. Arnaldo 715, São Paulo, SP, 01246-904, Brazil. .,Bone-Muscle Research Center, College of Nursing and Health Innovation, University of Texas-Arlington, 655 W. Mitchell Street, Arlington, TX, 76010, USA.
| | - Zhiying Wang
- Bone-Muscle Research Center, College of Nursing and Health Innovation, University of Texas-Arlington, 655 W. Mitchell Street, Arlington, TX, 76010, USA
| | - Jian Huang
- Bone-Muscle Research Center, College of Nursing and Health Innovation, University of Texas-Arlington, 655 W. Mitchell Street, Arlington, TX, 76010, USA
| | - Marco Brotto
- Bone-Muscle Research Center, College of Nursing and Health Innovation, University of Texas-Arlington, 655 W. Mitchell Street, Arlington, TX, 76010, USA
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Early Endothelial Activation Precedes Glycocalyx Degradation and Microvascular Dysfunction in Experimentally Induced Plasmodium falciparum and Plasmodium vivax Infection. Infect Immun 2020; 88:IAI.00895-19. [PMID: 32122938 DOI: 10.1128/iai.00895-19] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Accepted: 02/25/2020] [Indexed: 12/13/2022] Open
Abstract
Endothelial activation and microvascular dysfunction are key pathogenic processes in severe malaria. We evaluated the early role of these processes in experimentally induced Plasmodium falciparum and P. vivax infection. Participants were enrolled in induced blood-stage malaria clinical trials. Plasma osteoprotegerin, angiopoietin-2, and von Willebrand Factor (vWF) levels were measured as biomarkers of endothelial activation. Microvascular function was assessed using peripheral arterial tonometry and near-infrared spectroscopy, and the endothelial glycocalyx was assessed by sublingual videomicroscopy and measurement of biomarkers of degradation. Forty-five healthy, malaria-naive participants were recruited from 5 studies. Osteoprotegerin and vWF levels increased in participants following inoculation with P. vivax (n = 16) or P. falciparum (n = 15), with the angiopoietin-2 level also increasing in participants following inoculation with P. falciparum For both species, the most pronounced increase was seen in osteoprotegerin. This was particularly marked in participants inoculated with P. vivax, where the osteoprotegerin level correlated with the levels of parasitemia and the malaria clinical score. There were no changes in measures of endothelial glycocalyx or microvascular function. Plasma biomarkers of endothelial activation increased in early P. falciparum and P. vivax infection and preceded changes in the endothelial glycocalyx or microvascular function. The more pronounced increase in osteoprotegerin suggests that this biomarker may play a role in disease pathogenesis.
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Yeo TW, Weinberg JB, Lampah DA, Kenangalem E, Bush P, Chen Y, Price RN, Young S, Zhang HY, Millington D, Granger DL, Anstey NM. Glycocalyx Breakdown Is Associated With Severe Disease and Fatal Outcome in Plasmodium falciparum Malaria. Clin Infect Dis 2019; 69:1712-1720. [PMID: 30753363 PMCID: PMC6821254 DOI: 10.1093/cid/ciz038] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Accepted: 01/15/2019] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND Interactions between the endothelium and infected erythrocytes play a major role in the pathogenesis of falciparum malaria, with microvascular dysfunction and parasite sequestration associated with worsening outcomes. The glycocalyx is a carbohydrate-rich layer that lines the endothelium, with multiple roles in vascular homeostasis. The role of the glycocalyx in falciparum malaria and the association with disease severity has not been investigated. METHODS We prospectively enrolled Indonesian inpatients (aged ≥18 years) with severe (SM) or moderately severe (MSM) falciparum malaria, as defined by World Health Organization criteria, and healthy controls (HCs). On enrollment, blood and urine samples were collected concurrently with measurements of vascular nitric oxide (NO) bioavailability. Urine was assayed for glycocalyx breakdown products (glycosaminoglycans) using a dimethylmethylene blue (GAG-DMMB) and liquid chromatography-tandem mass spectrometry (GAG-MS) assay. RESULTS A total of 129 patients (SM = 43, MSM = 57, HC=29) were recruited. GAG-DMMB and GAG-MS (g/mol creatinine) were increased in SM (mean, 95% confidence interval: 3.98, 2.44-5.53 and 6.82, 5.19-8.44) compared to MSM patients (1.78, 1.27-2.29 and 4.87, 4.27-5.46) and HCs (0.22, 0.06-0.37 and 1.24, 0.89-1.59; P < 0.001). In SM patients, GAG-DMMB and GAG-MS were increased in those with a fatal outcome (n = 3; median, interquartile range: 6.72, 3.80-27.87 and 12.15, 7.88-17.20) compared to survivors (n = 39; 3.10, 0.46-4.5 and 4.64, 2.02-15.20; P = 0.03). Glycocalyx degradation was significantly associated with parasite biomass in both MSM (r = 0.48, GAG-DMMB and r = 0.43, GAG-MS; P < 0.001) and SM patients (r = 0.47, P = 0.002 and r = 0.33, P = 0.04) and inversely associated with endothelial NO bioavailability. CONCLUSIONS Increased endothelial glycocalyx breakdown is associated with severe disease and a fatal outcome in adults with falciparum malaria.
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Affiliation(s)
- Tsin W Yeo
- Global and Tropical Health Division, Menzies School of Health Research, Darwin, Northern Territory, Australia
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore
- Institute of Infectious Diseases and Epidemiology, Tan Tock Seng Hospital, Singapore
| | - J Brice Weinberg
- Duke University School of Medicine and VA Medical Center, Durham, North Carolina
| | - Daniel A Lampah
- Papuan Health and Community Development Foundation, Timika, Papua, Indonesia
| | - Enny Kenangalem
- Papuan Health and Community Development Foundation, Timika, Papua, Indonesia
- Mimika District Health Authority, Timika, Papua, Indonesia
| | - Peggy Bush
- Duke University School of Medicine and VA Medical Center, Durham, North Carolina
| | - Youwei Chen
- Duke University School of Medicine and VA Medical Center, Durham, North Carolina
| | - Richard N Price
- Global and Tropical Health Division, Menzies School of Health Research, Darwin, Northern Territory, Australia
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, United Kingdom
| | - Sarah Young
- Duke University School of Medicine and VA Medical Center, Durham, North Carolina
| | - Hao Y Zhang
- Duke University School of Medicine and VA Medical Center, Durham, North Carolina
| | - David Millington
- Duke University School of Medicine and VA Medical Center, Durham, North Carolina
| | | | - Nicholas M Anstey
- Global and Tropical Health Division, Menzies School of Health Research, Darwin, Northern Territory, Australia
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10
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Yeo TW, Bush PA, Chen Y, Young SP, Zhang H, Millington DS, Granger DL, Mwaikambo ED, Anstey NM, Weinberg JB. Glycocalyx breakdown is increased in African children with cerebral and uncomplicated falciparum malaria. FASEB J 2019; 33:14185-14193. [PMID: 31658834 DOI: 10.1096/fj.201901048rr] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Cerebral malaria (CM) from Plasmodium falciparum infection is associated with endothelial dysfunction and parasite sequestration. The glycocalyx (GCX), a carbohydrate-rich layer lining the endothelium, is crucial in vascular homeostasis. To evaluate the role of its loss in the pathogenesis of pediatric CM, we measured GCX degradation in Tanzanian children with World Health Organization-defined CM (n = 55), uncomplicated malaria (UM; n = 20), and healthy controls (HCs; n = 25). Urine GCX breakdown products [glycosaminoglycans (GAGs)] were quantified using dimethylmethylene blue (DMMB) and liquid chromatography-tandem mass spectrometry assays. DMMB-GAG and mass spectrometry (MS)-GAG (g/mol creatinine) were increased in CM and UM compared with HCs (P < 0.001), with no differences in DMMB-GAG and MS-GAG between CM and UM children or between those with and without a fatal outcome. In CM survivors, urinary GCX DMMB-GAG normalized by d 3. After adjusting for disease severity, DMMB-GAG was significantly associated with parasitemia [partial correlation coefficient (Pcorr) = 0.34; P = 0.01] and plasma TNF (Pcorr = 0.26; P = 0.04) and inversely with plasma and urine NO oxidation products [Pcorr = -0.31 (P = 0.01) and Pcorr = -0.26 (P = 0.03), respectively]. GCX breakdown is increased in children with falciparum malaria, with similar elevations in CM and UM. Endothelial GCX degradation may impair endothelial NO production, exacerbate adhesion-molecule expression, exposure, and parasite sequestration, and contribute to malaria pathogenesis.-Yeo, T. W., Bush, P. A., Chen, Y., Young, S. P., Zhang, H., Millington, D. S., Granger, D. L., Mwaikambo, E. D., Anstey, N. M., Weinberg, J. B. Glycocalyx breakdown is increased in African children with cerebral and uncomplicated falciparum malaria.
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Affiliation(s)
- Tsin W Yeo
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore.,National Centre for Infectious Diseases, Tan Tock Seng Hospital, Singapore.,Menzies School of Health Research, Charles Darwin University, Darwin, Northern Territory, Australia
| | - Peggy A Bush
- Duke University-Veterans Affairs (VA) Medical Center, Durham, North Carolina, USA
| | - Youwei Chen
- Duke University-Veterans Affairs (VA) Medical Center, Durham, North Carolina, USA
| | - Sarah P Young
- Duke University-Veterans Affairs (VA) Medical Center, Durham, North Carolina, USA
| | - Haoyue Zhang
- Duke University-Veterans Affairs (VA) Medical Center, Durham, North Carolina, USA
| | - David S Millington
- Duke University-Veterans Affairs (VA) Medical Center, Durham, North Carolina, USA
| | - Donald L Granger
- University of Utah-Veterans Affairs (VA) Medical Center, Salt Lake City, Utah, USA
| | | | - Nicholas M Anstey
- Menzies School of Health Research, Charles Darwin University, Darwin, Northern Territory, Australia
| | - J Brice Weinberg
- Duke University-Veterans Affairs (VA) Medical Center, Durham, North Carolina, USA
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11
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Takaya S, Kutsuna S, Suzuki T, Komaki-Yasuda K, Kano S, Ohmagari N. Case Report: Plasmodium knowlesi Infection with Rhabdomyolysis in a Japanese Traveler to Palawan, the Philippines. Am J Trop Med Hyg 2019; 99:967-969. [PMID: 30182921 DOI: 10.4269/ajtmh.18-0348] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Skeletal muscle is known to be damaged by falciparum malaria via sequestration of infected erythrocytes. We present a case of rhabdomyolysis caused by Plasmodium knowlesi infection. The patient had fever, myalgia, and muscle weakness 5 days after returning to Japan from Palawan, the Philippines. Blood test revealed thrombocytopenia and an elevated creatine kinase level. Although rhabdomyolysis resolved with fluid therapy, fever of 24-hour cycle continued and thrombocytopenia intensified. On day 7 of illness, Giemsa-stained thin blood smear revealed malaria parasites, with a parasite count of 2,380/μL, which were morphologically indistinguishable between P. knowlesi and Plasmodium malariae. Rapid diagnostic test showed a negative result. The pathogen was later confirmed to be P. knowlesi by nested polymerase chain reaction (PCR). The patient was successfully treated with artemether/lumefantrine. This case suggests that knowlesi malaria might be able to cause skeletal muscle damage.
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Affiliation(s)
- Saho Takaya
- Diseases Control and Prevention Center, National Center for Global Health and Medicine, Tokyo, Japan
| | - Satoshi Kutsuna
- Diseases Control and Prevention Center, National Center for Global Health and Medicine, Tokyo, Japan
| | - Tetsuya Suzuki
- Diseases Control and Prevention Center, National Center for Global Health and Medicine, Tokyo, Japan
| | - Kanako Komaki-Yasuda
- Department of Tropical Medicine and Malaria, National Center for Global Health and Medicine Research Institute, Tokyo, Japan
| | - Shigeyuki Kano
- Department of Tropical Medicine and Malaria, National Center for Global Health and Medicine Research Institute, Tokyo, Japan
| | - Norio Ohmagari
- Diseases Control and Prevention Center, National Center for Global Health and Medicine, Tokyo, Japan
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12
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Kingston HW, Ghose A, Rungpradubvong V, Herdman MT, Plewes K, Ishioka H, Leopold SJ, Maude RJ, Intharabut B, Mohanty S, Day NPJ, White NJ, Hossain MA, Anstey NM, Dondorp AM. Does reduced oxygen delivery cause lactic acidosis in falciparum malaria? An observational study. Malar J 2019; 18:97. [PMID: 30909915 PMCID: PMC6434797 DOI: 10.1186/s12936-019-2733-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Accepted: 03/18/2019] [Indexed: 12/18/2022] Open
Abstract
Background Lactic acidosis with an elevated lactate–pyruvate ratio suggesting anoxia is a common feature of severe falciparum malaria. High lactate levels are associated with parasitized erythrocyte sequestration in the microcirculation. To assess if there is an additional contribution to hyperlactataemia from relatively inadequate total oxygen delivery, oxygen consumption and delivery were investigated in patients with malaria. Methods Adult Bangladeshi and Indian patients with uncomplicated (N = 50) or severe (N = 46) falciparum malaria or suspected bacterial sepsis (N = 27) and healthy participants as controls (N = 26) were recruited at Chittagong Medical College Hospital, Chittagong, Bangladesh and Ispat General Hospital, Rourkela, India. Oxygen delivery (DO2I) was estimated from pulse oximetry, echocardiographic estimates of cardiac index and haematocrit. Oxygen consumption (VO2I) was estimated by expired gas collection. Results VO2I was elevated in uncomplicated median (IQR) 185.1 ml/min/m2 (135–215.9) and severe malaria 192 ml/min/m2 (140.7–227.9) relative to healthy persons 107.9 ml/min/m2 (69.9–138.1) (both p < 0.001). Median DO2I was similar in uncomplicated 515 ml/min/m2 (432–612) and severe 487 ml/min/m2 (382–601) malaria and healthy persons 503 ml/min/m2 (447–517) (p = 0.27 and 0.89, respectively). The VO2/DO2 ratio was, therefore, increased by similar amounts in both uncomplicated 0.35 (0.28–0.44) and severe malaria 0.38 (0.29–0.48) relative to healthy participants 0.23 (0.17–0.28) (both p < 0.001). VO2I, DO2I and VO2/DO2 did not correlate with plasma lactate concentrations in severe malaria. Conclusions Reduced total oxygen delivery is not a major contributor to lactic acidosis in severe falciparum malaria. Electronic supplementary material The online version of this article (10.1186/s12936-019-2733-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Hugh W Kingston
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand. .,Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, 0909, Australia. .,Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, Churchill Hospital, Oxford, OX3 7LJ, UK.
| | | | - Voravut Rungpradubvong
- Division of Cardiology, Department of Medicine, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand.,Cardiac Center, King Chulalongkorn Memorial Hospital, Bangkok, Thailand
| | - M Trent Herdman
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand.,Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, Churchill Hospital, Oxford, OX3 7LJ, UK
| | - Katherine Plewes
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand.,Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, Churchill Hospital, Oxford, OX3 7LJ, UK
| | - Haruhiko Ishioka
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand.,Department of Clinical Tropical Medicine, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand
| | - Stije J Leopold
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand.,Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, Churchill Hospital, Oxford, OX3 7LJ, UK
| | - Richard J Maude
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand.,Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, Churchill Hospital, Oxford, OX3 7LJ, UK
| | - Benjamas Intharabut
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand
| | | | - Nicholas P J Day
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand.,Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, Churchill Hospital, Oxford, OX3 7LJ, UK
| | - Nicholas J White
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand.,Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, Churchill Hospital, Oxford, OX3 7LJ, UK
| | | | - Nicholas M Anstey
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, 0909, Australia
| | - Arjen M Dondorp
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand.,Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, Churchill Hospital, Oxford, OX3 7LJ, UK
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13
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Barber BE, Grigg MJ, Piera KA, William T, Cooper DJ, Plewes K, Dondorp AM, Yeo TW, Anstey NM. Intravascular haemolysis in severe Plasmodium knowlesi malaria: association with endothelial activation, microvascular dysfunction, and acute kidney injury. Emerg Microbes Infect 2018; 7:106. [PMID: 29872039 PMCID: PMC5988665 DOI: 10.1038/s41426-018-0105-2] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Revised: 05/03/2018] [Accepted: 05/08/2018] [Indexed: 12/29/2022]
Abstract
Plasmodium knowlesi occurs throughout Southeast Asia, and is the most common cause of human malaria in Malaysia. Severe disease in humans is characterised by high parasite biomass, reduced red blood cell deformability, endothelial activation and microvascular dysfunction. However, the roles of intravascular haemolysis and nitric oxide (NO)-dependent endothelial dysfunction, important features of severe falciparum malaria, have not been evaluated, nor their role in acute kidney injury (AKI). In hospitalised Malaysian adults with severe (n = 48) and non-severe (n = 154) knowlesi malaria, and in healthy controls (n = 50), we measured cell-free haemoglobin (CFHb) and assessed associations with the endothelial Weibel–Palade body (WPB) constituents, angiopoietin-2 and osteoprotegerin, endothelial and microvascular function, and other markers of disease severity. CFHb was increased in knowlesi malaria in proportion to disease severity, and to a greater extent than previously reported in severe falciparum malaria patients from the same study cohort. In knowlesi malaria, CFHb was associated with parasitaemia, and independently associated with angiopoietin-2 and osteoprotegerin. As with angiopoietin-2, osteoprotegerin was increased in proportion to disease severity, and independently associated with severity markers including creatinine, lactate, interleukin-6, endothelial cell adhesion molecules ICAM-1 and E-selectin, and impaired microvascular reactivity. Osteoprotegerin was also independently associated with NO-dependent endothelial dysfunction. AKI was found in 88% of those with severe knowlesi malaria. Angiopoietin-2 and osteoprotegerin were both independent risk factors for acute kidney injury. Our findings suggest that haemolysis-mediated endothelial activation and release of WPB constituents is likely a key contributor to end-organ dysfunction, including AKI, in severe knowlesi malaria.
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Affiliation(s)
- Bridget E Barber
- Global and Tropical Health Division, Menzies School of Health Research, Darwin, NT, Australia. .,Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, Kota Kinabalu, Sabah, Malaysia.
| | - Matthew J Grigg
- Global and Tropical Health Division, Menzies School of Health Research, Darwin, NT, Australia.,Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, Kota Kinabalu, Sabah, Malaysia
| | - Kim A Piera
- Global and Tropical Health Division, Menzies School of Health Research, Darwin, NT, Australia
| | - Timothy William
- Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, Kota Kinabalu, Sabah, Malaysia.,Jesselton Medical Centre, Kota Kinabalu, Sabah, Malaysia.,Clinical Research Centre, Queen Elizabeth Hospital, Kota Kinabalu, Sabah, Malaysia
| | - Daniel J Cooper
- Global and Tropical Health Division, Menzies School of Health Research, Darwin, NT, Australia.,Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, Kota Kinabalu, Sabah, Malaysia
| | - Katherine Plewes
- Mahidol Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand.,Department of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Arjen M Dondorp
- Mahidol Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand.,Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK
| | - Tsin W Yeo
- Global and Tropical Health Division, Menzies School of Health Research, Darwin, NT, Australia.,Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, Kota Kinabalu, Sabah, Malaysia.,Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore.,Institute of Infectious Disease and Epidemiology, Tan Tock Seng Hospital, Singapore, Singapore
| | - Nicholas M Anstey
- Global and Tropical Health Division, Menzies School of Health Research, Darwin, NT, Australia.,Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, Kota Kinabalu, Sabah, Malaysia
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14
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Bonneaud C, Sepil I, Wilfert L, Calsbeek R. Plasmodium Infections in Natural Populations of Anolis sagrei Reflect Tolerance Rather Than Susceptibility. Integr Comp Biol 2018; 57:352-361. [PMID: 28859403 PMCID: PMC5886326 DOI: 10.1093/icb/icx044] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Parasites can represent formidable selection pressures for hosts, but the cost of infection is sometimes difficult to demonstrate in natural populations. While parasite exploitation strategies may, in some instances, actually inflict low costs on their hosts, the response of hosts to infection is also likely to determine whether or not these costs can be detected. Indeed, costs of infection may be obscured if infected individuals in the wild are those that are the most tolerant, rather than the most susceptible, to infection. Here we test this hypothesis in two natural populations of Anolis sagrei, one of the most common anole lizard of the Bahamas. Plasmodium parasites were detected in > 7% of individuals and belonged to two distinct clades: P. mexicanum and P. floriensis. Infected individuals displayed greater body condition than non-infected ones and we found no association between infection status, stamina, and survival to the end of the breeding season. Furthermore, we found no significant difference in the immuno-competence (measured as a response to phytohemagglutinin challenge) of infected versus non-infected individuals. Taken together, our results suggest that the infected individuals that are caught in the wild are those most able to withstand the cost of the infection and that susceptible, infected individuals have been removed from the population (i.e., through disease-induced mortality). This study highlights the need for caution when interpreting estimates of infection costs in natural populations, as costs may appear low either when parasites exploitation strategies truly inflict low costs on their hosts or when those costs are so high that susceptible hosts are removed from the population.
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Affiliation(s)
- Camille Bonneaud
- Centre for Ecology and Conservation, University of Exeter, Penryn, TR10?9EF, UK
| | - Irem Sepil
- Department of Zoology, University of Oxford, Oxford, OX1?3PS, UK
| | - Lena Wilfert
- Centre for Ecology and Conservation, University of Exeter, Penryn, TR10?9EF, UK
| | - Ryan Calsbeek
- Department of Biological Sciences, Dartmouth College, New Hampshire, Hanover, NH 03755, USA
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15
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The Plasmodium falciparum transcriptome in severe malaria reveals altered expression of genes involved in important processes including surface antigen-encoding var genes. PLoS Biol 2018; 16:e2004328. [PMID: 29529020 PMCID: PMC5864071 DOI: 10.1371/journal.pbio.2004328] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Revised: 03/22/2018] [Accepted: 02/16/2018] [Indexed: 01/13/2023] Open
Abstract
Within the human host, the malaria parasite Plasmodium falciparum is exposed to multiple selection pressures. The host environment changes dramatically in severe malaria, but the extent to which the parasite responds to-or is selected by-this environment remains unclear. From previous studies, the parasites that cause severe malaria appear to increase expression of a restricted but poorly defined subset of the PfEMP1 variant, surface antigens. PfEMP1s are major targets of protective immunity. Here, we used RNA sequencing (RNAseq) to analyse gene expression in 44 parasite isolates that caused severe and uncomplicated malaria in Papuan patients. The transcriptomes of 19 parasite isolates associated with severe malaria indicated that these parasites had decreased glycolysis without activation of compensatory pathways; altered chromatin structure and probably transcriptional regulation through decreased histone methylation; reduced surface expression of PfEMP1; and down-regulated expression of multiple chaperone proteins. Our RNAseq also identified novel associations between disease severity and PfEMP1 transcripts, domains, and smaller sequence segments and also confirmed all previously reported associations between expressed PfEMP1 sequences and severe disease. These findings will inform efforts to identify vaccine targets for severe malaria and also indicate how parasites adapt to-or are selected by-the host environment in severe malaria.
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16
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Plewes K, Turner GD, Dondorp AM. Pathophysiology, clinical presentation, and treatment of coma and acute kidney injury complicating falciparum malaria. Curr Opin Infect Dis 2018; 31:69-77. [PMID: 29206655 PMCID: PMC5768231 DOI: 10.1097/qco.0000000000000419] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
PURPOSE OF REVIEW Cerebral impairment and acute kidney injury (AKI) are independent predictors of mortality in both adults and children with severe falciparum malaria. In this review, we present recent advances in understanding the pathophysiology, clinical features, and management of these complications of severe malaria, and discuss future areas of research. RECENT FINDINGS Cerebral malaria and AKI are serious and well recognized complications of severe malaria. Common pathophysiological pathways include impaired microcirculation, due to sequestration of parasitized erythrocytes, systemic inflammatory responses, and endothelial activation. Recent MRI studies show significant brain swelling in both adults and children with evidence of posterior reversible encephalopathy syndrome-like syndrome although targeted interventions including mannitol and dexamethasone are not beneficial. Recent work shows association of cell-free hemoglobin oxidation stress involved in the pathophysiology of AKI in both adults and children. Paracetamol protected renal function likely by inhibiting cell-free-mediated oxidative stress. It is unclear if heme-mediated endothelial activation or oxidative stress is involved in cerebral malaria. SUMMARY The direct causes of cerebral and kidney dysfunction remain incompletely understood. Optimal treatment involves prompt diagnosis and effective antimalarial treatment with artesunate. Renal replacement therapy reduces mortality in AKI but delayed diagnosis is an issue.
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Affiliation(s)
- Katherine Plewes
- Faculty of Tropical Medicine, Mahidol Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand
- Division of Infectious Diseases, Department of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Gareth D.H. Turner
- Department of Cellular Pathology, John Radcliffe Hospital
- Nuffield Department of Clinical Medicine, Center for Tropical Medicine and Global Health, University of Oxford, Oxford, UK
| | - Arjen M. Dondorp
- Faculty of Tropical Medicine, Mahidol Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand
- Nuffield Department of Clinical Medicine, Center for Tropical Medicine and Global Health, University of Oxford, Oxford, UK
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17
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Barber BE, Grigg MJ, William T, Piera KA, Boyle MJ, Yeo TW, Anstey NM. Effects of Aging on Parasite Biomass, Inflammation, Endothelial Activation, Microvascular Dysfunction and Disease Severity in Plasmodium knowlesi and Plasmodium falciparum Malaria. J Infect Dis 2017; 215:1908-1917. [PMID: 28863470 DOI: 10.1093/infdis/jix193] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Accepted: 04/15/2017] [Indexed: 02/06/2023] Open
Abstract
Background In populations pauci-immune to malaria, risk of severe malaria increases with age. This is particularly apparent in Plasmodium knowlesi malaria. However, pathophysiological mechanisms underlying knowlesi malaria, and of the age-related increase in risk of severe malaria in general, are poorly understood. Methods In Malaysian patients aged ≥12 years with severe (n = 47) and nonsevere (n = 99) knowlesi malaria, severe (n = 21) and nonsevere (n = 109) falciparum malaria, and healthy controls (n = 50), we measured parasite biomass, systemic inflammation (interleukin 6 [IL-6]), endothelial activation (angiopoietin-2), and microvascular function, and evaluated the effects of age. Results Plasmodium knowlesi parasitemia correlated with age (Spearman's correlation coefficient [rs] = 0.36; P < .0001). In knowlesi malaria, IL-6, angiopoietin-2, and microvascular dysfunction were increased in severe compared to nonsevere disease, and all correlated with age, independent of parasitemia. In falciparum malaria, angiopoietin-2 increased with age, independent of parasite biomass (histidine-rich protein 2 [HRP2]). Independent risk factors for severe malaria included parasitemia and angiopoietin-2 in knowlesi malaria, and HRP2, angiopoietin-2, and microvascular dysfunction in falciparum malaria. Conclusions Parasite biomass, endothelial activation, and microvascular dysfunction are associated with severe disease in knowlesi malaria and likely contribute to pathogenesis. The association of each of these processes with aging may account for the greater severity of malaria observed in older adults in low-endemic regions.
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Affiliation(s)
- Bridget E Barber
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Northern Territory, Australia.,Infectious Diseases Society, Sabah-Menzies School of Health Research Clinical Research Unit, Queen Elizabeth Hospital
| | - Matthew J Grigg
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Northern Territory, Australia.,Infectious Diseases Society, Sabah-Menzies School of Health Research Clinical Research Unit, Queen Elizabeth Hospital
| | - Timothy William
- Infectious Diseases Society, Sabah-Menzies School of Health Research Clinical Research Unit, Queen Elizabeth Hospital.,Jesselton Medical Centre, Kota Kinabalu, Sabah, Malaysia
| | - Kim A Piera
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Northern Territory, Australia
| | - Michelle J Boyle
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Northern Territory, Australia.,Centre for Biomedical Research, Burnet Institute, Melbourne, Victoria, Australia
| | - Tsin W Yeo
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Northern Territory, Australia.,Infectious Diseases Society, Sabah-Menzies School of Health Research Clinical Research Unit, Queen Elizabeth Hospital.,Lee Kong Chian School of Medicine, Nanyang Technological University.,Institute of Infectious Disease and Epidemiology, Tan Tock Seng Hospital, Singapore
| | - Nicholas M Anstey
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Northern Territory, Australia.,Infectious Diseases Society, Sabah-Menzies School of Health Research Clinical Research Unit, Queen Elizabeth Hospital
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18
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Yeo TW, Florence SM, Kalingonji AR, Chen Y, Granger DL, Anstey NM, Mwaikambo ED, Weinberg JB. Decreased Microvascular Function in Tanzanian Children With Severe and Uncomplicated Falciparum Malaria. Open Forum Infect Dis 2017; 4:ofx079. [PMID: 28852670 PMCID: PMC5569702 DOI: 10.1093/ofid/ofx079] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Accepted: 04/19/2017] [Indexed: 11/13/2022] Open
Abstract
Microvascular function and oxygen consumption affect oxygen homeostasis but have not been assessed in African children with malaria. Microvascular function in Tanzanian children with severe malaria (SM) or uncomplicated malaria were 39% and 72%, respectively, of controls (P < .001). Uncomplicated malaria (P = .04), not SM (P = .06), children had increased oxygen consumption compared with controls.
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Affiliation(s)
- Tsin W Yeo
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore.,Communicable Disease Centre, Institute of Infectious Diseases and Epidemiology, Tan Tock Seng Hospital, Singapore.,Menzies School of Health Research and Charles Darwin University, Darwin, Australia
| | | | | | - Youwei Chen
- Duke University and V.A. Medical Centers, Durham, North Carolina; and
| | | | - Nicholas M Anstey
- Menzies School of Health Research and Charles Darwin University, Darwin, Australia
| | | | - J Brice Weinberg
- Duke University and V.A. Medical Centers, Durham, North Carolina; and
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19
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The effect of malaria and anti-malarial drugs on skeletal and cardiac muscles. Malar J 2016; 15:524. [PMID: 27806725 PMCID: PMC5093925 DOI: 10.1186/s12936-016-1577-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Accepted: 10/28/2016] [Indexed: 11/27/2022] Open
Abstract
Malaria remains one of the most important infectious diseases in the world, being a significant public health problem associated with poverty and it is one of the main obstacles to the economy of an endemic country. Among the several complications, the effects of malaria seem to target the skeletal muscle system, leading to symptoms, such as muscle aches, muscle contractures, muscle fatigue, muscle pain, and muscle weakness. Malaria cause also parasitic coronary artery occlusion. This article reviews the current knowledge regarding the effect of malaria disease and the anti-malarial drugs on skeletal and cardiac muscles. Research articles and case report publications that addressed aspects that are important for understanding the involvement of malaria parasites and anti-malarial therapies affecting skeletal and cardiac muscles were analysed and their findings summarized. Sequestration of red blood cells, increased levels of serum creatine kinase and reduced muscle content of essential contractile proteins are some of the potential biomarkers of the damage levels of skeletal and cardiac muscles. These biomarkers might be useful for prevention of complications and determining the effectiveness of interventions designed to protect cardiac and skeletal muscles from malaria-induced damage.
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20
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Barber BE, William T, Grigg MJ, Piera KA, Chen Y, Wang H, Weinberg JB, Yeo TW, Anstey NM. Nitric Oxide-Dependent Endothelial Dysfunction and Reduced Arginine Bioavailability in Plasmodium vivax Malaria but No Greater Increase in Intravascular Hemolysis in Severe Disease. J Infect Dis 2016; 214:1557-1564. [PMID: 27630198 DOI: 10.1093/infdis/jiw427] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Accepted: 09/06/2016] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Pathogenesis of severe Plasmodium vivax malaria is poorly understood. Endothelial dysfunction and reduced nitric oxide (NO) bioavailability characterize severe falciparum malaria, but have not been assessed in severe vivax malaria. METHODS In patients with severe vivax malaria (n = 9), patients with nonsevere vivax malaria (n = 58), and healthy controls (n = 79), we measured NO-dependent endothelial function by using reactive hyperemia-peripheral arterial tonometry (RH-PAT) and assessed associations with arginine, asymmetric dimethylarginine (ADMA), and hemolysis. RESULTS The L-arginine level and the L-arginine to ADMA ratio (a measure of L-arginine bioavailability) were reduced in patients with severe vivax malaria and those with nonsevere vivax malaria, compared with healthy controls (median L-arginine level, 65, 66, and 98 µmol/mL, respectively [P = .0001]; median L-arginine to ADMA ratio, 115, 125, and 187, respectively [P = .0001]). Endothelial function was impaired in proportion to disease severity (median RH-PAT index, 1.49, 1.73, and 1.97 in patients with severe vivax malaria, those with nonsevere vivax malaria, and healthy controls, respectively; P = .018) and was associated with the L-arginine to ADMA ratio. While the posttreatment fall in hemoglobin level was greater in severe vivax malaria as compared to nonsevere vivax malaria (2.5 vs 1 g/dL; P = .0001), markers of intravascular hemolysis were not higher in severe disease. CONCLUSIONS Endothelial function is impaired in nonsevere and severe vivax malaria, is associated with reduced L-arginine bioavailability, and may contribute to microvascular pathogenesis. Severe disease appears to be more associated with extravascular hemolysis than with intravascular hemolysis.
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Affiliation(s)
- Bridget E Barber
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University.,Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit
| | - Timothy William
- Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit.,Jesselton Medical Center, Kota Kinabalu, Malaysia
| | - Matthew J Grigg
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University.,Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit
| | - Kim A Piera
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University
| | - Youwei Chen
- Duke University Medical Center.,VA Medical Center, Durham, North Carolina
| | - Hao Wang
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University
| | - J Brice Weinberg
- Duke University Medical Center.,VA Medical Center, Durham, North Carolina
| | - Tsin W Yeo
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University.,Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit.,Lee Kong Chian School of Medicine, Nanyang Technological University.,Institute of Infectious Disease and Epidemiology, Tan Tock Seng Hospital, Singapore
| | - Nicholas M Anstey
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University.,Department of Infectious Diseases, Royal Darwin Hospital, Darwin, Australia.,Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit
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21
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Weinberg JB, Volkheimer AD, Rubach MP, Florence SM, Mukemba JP, Kalingonji AR, Langelier C, Chen Y, Bush M, Yeo TW, Granger DL, Anstey NM, Mwaikambo ED. Monocyte polarization in children with falciparum malaria: relationship to nitric oxide insufficiency and disease severity. Sci Rep 2016; 6:29151. [PMID: 27385484 PMCID: PMC4935839 DOI: 10.1038/srep29151] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Accepted: 06/15/2016] [Indexed: 12/23/2022] Open
Abstract
We earlier established that nitric oxide (NO) is protective against severe malaria and that arginine and NO levels are reduced in malaria patients. We now show that an M2-like blood monocyte phenotype is significantly associated with hypoargininemia, NO insufficiency, and disease severity in Tanzanian children with falciparum malaria. Compared to control children (n = 106), children with moderately severe (n = 77) and severe falciparum malaria (n = 129) had significantly higher mononuclear cell arginase 1 mRNA, protein, and enzyme activity; lower NOS2 mRNA; lower plasma arginine; and higher plasma IL-10, IL-13, and IL-4. In addition, monocyte CD206 and CD163 and plasma soluble CD163 were elevated. Multivariate logistic regression analysis revealed a significant correlation of risk of severe malaria with both plasma IL-10 and soluble CD163 levels. Monocyte M2 skewing likely contributes to NO bioinsufficiency in falciparum malaria in children. Treatments that reverse the M2 polarization may have potential as adjunctive treatment for malaria.
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Affiliation(s)
- J Brice Weinberg
- Duke University and V.A. Medical Centers, Durham, North Carolina, USA
| | | | - Matthew P Rubach
- Duke University and V.A. Medical Centers, Durham, North Carolina, USA
| | | | | | | | | | - Youwei Chen
- Duke University and V.A. Medical Centers, Durham, North Carolina, USA
| | - Margaret Bush
- Duke University and V.A. Medical Centers, Durham, North Carolina, USA
| | - Tsin W Yeo
- Menzies School of Health Research and Charles Darwin University, Darwin, Australia
| | - Donald L Granger
- University of Utah and V.A. Medical Centers, Salt Lake City, Utah, USA
| | - Nicholas M Anstey
- Menzies School of Health Research and Charles Darwin University, Darwin, Australia
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22
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Duffy MF, Noviyanti R, Tsuboi T, Feng ZP, Trianty L, Sebayang BF, Takashima E, Sumardy F, Lampah DA, Turner L, Lavstsen T, Fowkes FJI, Siba P, Rogerson SJ, Theander TG, Marfurt J, Price RN, Anstey NM, Brown GV, Papenfuss AT. Differences in PfEMP1s recognized by antibodies from patients with uncomplicated or severe malaria. Malar J 2016; 15:258. [PMID: 27149991 PMCID: PMC4858840 DOI: 10.1186/s12936-016-1296-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Accepted: 04/15/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) variants are encoded by var genes and mediate pathogenic cytoadhesion and antigenic variation in malaria. PfEMP1s can be broadly divided into three principal groups (A, B and C) and they contain conserved arrangements of functional domains called domain cassettes. Despite their tremendous diversity there is compelling evidence that a restricted subset of PfEMP1s is expressed in severe disease. In this study antibodies from patients with severe and uncomplicated malaria were compared for differences in reactivity with a range of PfEMP1s to determine whether antibodies to particular PfEMP1 domains were associated with severe or uncomplicated malaria. METHODS Parts of expressed var genes in a severe malaria patient were identified by RNAseq and several of these partial PfEMP1 domains were expressed together with others from laboratory isolates. Antibodies from Papuan patients to these parts of multiple PfEMP1 proteins were measured. RESULTS Patients with uncomplicated malaria were more likely to have antibodies that recognized PfEMP1 of Group C type and recognized a broader repertoire of group A and B PfEMP1s than patients with severe malaria. CONCLUSION These data suggest that exposure to a broad range of group A and B PfEMP1s is associated with protection from severe disease in Papua, Indonesia.
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Affiliation(s)
- Michael F. Duffy
- />Department of Medicine, Royal Melbourne Hospital, The University of Melbourne, The Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria Australia
| | - Rintis Noviyanti
- />The Eijkman Institute for Molecular Biology, Jakarta, Indonesia
| | - Takafumi Tsuboi
- />Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Ehime Japan
| | - Zhi-Ping Feng
- />Bioinformatics Division, The Walter & Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- />Department of Medical Biology, University of Melbourne, Parkville, Victoria Australia
| | - Leily Trianty
- />The Eijkman Institute for Molecular Biology, Jakarta, Indonesia
| | - Boni F. Sebayang
- />The Eijkman Institute for Molecular Biology, Jakarta, Indonesia
| | - Eizo Takashima
- />Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Ehime Japan
| | - Fransisca Sumardy
- />Department of Medicine, Royal Melbourne Hospital, The University of Melbourne, The Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria Australia
| | - Daniel A. Lampah
- />Timika Malaria Research Program, Papuan Health and Community Development Foundation, Timika, Papua Indonesia
| | - Louise Turner
- />Centre for Medical Parasitology, University of Copenhagen, Copenhagen, Denmark
| | - Thomas Lavstsen
- />Centre for Medical Parasitology, University of Copenhagen, Copenhagen, Denmark
| | | | - Peter Siba
- />The Papua New Guinea Institute for Medical Research, Madang, Papua New Guinea
| | - Stephen J. Rogerson
- />Department of Medicine, Royal Melbourne Hospital, The University of Melbourne, The Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria Australia
| | - Thor G. Theander
- />Centre for Medical Parasitology, University of Copenhagen, Copenhagen, Denmark
| | - Jutta Marfurt
- />Global and Tropical Health Division, Menzies School of Health Research, Charles Darwin University, Darwin, NT Australia
| | - Ric N. Price
- />Global and Tropical Health Division, Menzies School of Health Research, Charles Darwin University, Darwin, NT Australia
- />Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK
| | - Nicholas M. Anstey
- />Global and Tropical Health Division, Menzies School of Health Research, Charles Darwin University, Darwin, NT Australia
| | - Graham V. Brown
- />The Nossal Institute for Global Health, The University of Melbourne, Parkville, Victoria Australia
| | - Anthony T. Papenfuss
- />Bioinformatics Division, The Walter & Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- />Department of Medical Biology, University of Melbourne, Parkville, Victoria Australia
- />Peter MacCallum Cancer Centre, East Melbourne, Victoria, Australia
- />Sir Peter MacCallum Department of Oncology, University of Melbourne, Melbourne, Victoria Australia
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23
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Portnoy E, Vakruk N, Bishara A, Shmuel M, Magdassi S, Golenser J, Eyal S. Indocyanine Green Liposomes for Diagnosis and Therapeutic Monitoring of Cerebral Malaria. Am J Cancer Res 2016; 6:167-76. [PMID: 26877776 PMCID: PMC4729766 DOI: 10.7150/thno.13653] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Accepted: 10/12/2015] [Indexed: 01/13/2023] Open
Abstract
Cerebral malaria (CM) is a major cause of death of Plasmodium falciparum infection. Misdiagnosis of CM often leads to treatment delay and mortality. Conventional brain imaging technologies are rarely applicable in endemic areas. Here we address the unmet need for a simple, non-invasive imaging methodology for early diagnosis of CM. This study presents the diagnostic and therapeutic monitoring using liposomes containing the FDA-approved fluorescent dye indocyanine green (ICG) in a CM murine model. Increased emission intensity of liposomal ICG was demonstrated in comparison with free ICG. The Liposomal ICG's emission was greater in the brains of the infected mice compared to naïve mice and drug treated mice (where CM was prevented). Histological analyses suggest that the accumulation of liposomal ICG in the cerebral vasculature is due to extensive uptake mediated by activated phagocytes. Overall, liposomal ICG offers a valuable diagnostic tool and a biomarker for effectiveness of CM treatment, as well as other diseases that involve inflammation and blood vessel occlusion.
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24
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Deroost K, Pham TT, Opdenakker G, Van den Steen PE. The immunological balance between host and parasite in malaria. FEMS Microbiol Rev 2015; 40:208-57. [PMID: 26657789 DOI: 10.1093/femsre/fuv046] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/04/2015] [Indexed: 12/16/2022] Open
Abstract
Coevolution of humans and malaria parasites has generated an intricate balance between the immune system of the host and virulence factors of the parasite, equilibrating maximal parasite transmission with limited host damage. Focusing on the blood stage of the disease, we discuss how the balance between anti-parasite immunity versus immunomodulatory and evasion mechanisms of the parasite may result in parasite clearance or chronic infection without major symptoms, whereas imbalances characterized by excessive parasite growth, exaggerated immune reactions or a combination of both cause severe pathology and death, which is detrimental for both parasite and host. A thorough understanding of the immunological balance of malaria and its relation to other physiological balances in the body is of crucial importance for developing effective interventions to reduce malaria-related morbidity and to diminish fatal outcomes due to severe complications. Therefore, we discuss in this review the detailed mechanisms of anti-malarial immunity, parasite virulence factors including immune evasion mechanisms and pathogenesis. Furthermore, we propose a comprehensive classification of malaria complications according to the different types of imbalances.
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Affiliation(s)
- Katrien Deroost
- Laboratory of Immunobiology, Rega Institute for Medical Research, KU Leuven - University of Leuven, 3000 Leuven, Belgium The Francis Crick Institute, Mill Hill Laboratory, London, NW71AA, UK
| | - Thao-Thy Pham
- Laboratory of Immunobiology, Rega Institute for Medical Research, KU Leuven - University of Leuven, 3000 Leuven, Belgium
| | - Ghislain Opdenakker
- Laboratory of Immunobiology, Rega Institute for Medical Research, KU Leuven - University of Leuven, 3000 Leuven, Belgium
| | - Philippe E Van den Steen
- Laboratory of Immunobiology, Rega Institute for Medical Research, KU Leuven - University of Leuven, 3000 Leuven, Belgium
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25
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Aung NM, Kaung M, Kyi TT, Kyaw MP, Min M, Htet ZW, Anstey NM, Kyi MM, Hanson J. The Safety of a Conservative Fluid Replacement Strategy in Adults Hospitalised with Malaria. PLoS One 2015; 10:e0143062. [PMID: 26581060 PMCID: PMC4651424 DOI: 10.1371/journal.pone.0143062] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2015] [Accepted: 10/22/2015] [Indexed: 12/29/2022] Open
Abstract
Background A conservative approach to fluid resuscitation improves survival in children with severe malaria; however, this strategy has not been formally evaluated in adults with the disease. Methods Adults hospitalised with malaria at two tertiary referral hospitals in Myanmar received intravenous fluid replacement with isotonic saline, administered at a maintenance rate using a simple weight-based algorithm. Clinical and biochemical indices were followed sequentially. Results Of 61 adults enrolled, 34 (56%) had Plasmodium falciparum mono-infection, 17 (28%) Plasmodium vivax mono-infection and 10 (16%) mixed infection; 27 (44%) patients were at high risk of death (P. falciparum infection and RCAM score ≥ 2). In the first six hours of hospitalisation patients received a mean 1.7 ml/kg/hour (range: 1.3–2.2) of intravenous fluid and were able to drink a mean of 0.8 ml/kg/hour (range: 0–3). Intravenous fluid administration and oral intake were similar for the remainder of the first 48 hours of hospitalisation. All 61 patients survived to discharge. No patient developed Adult Respiratory Distress Syndrome, a requirement for renal replacement therapy or hypotension (mean arterial pressure < 60mmHg). Plasma lactate was elevated (> 2 mmol/L) on enrolment in 26 (43%) patients but had declined by 6 hours in 25 (96%) and was declining at 24 hours in the other patient. Plasma creatinine was elevated (> 120 μmol/L) on enrolment in 17 (28%) patients, but was normal or falling in 16 (94%) at 48 hours and declining in the other patient by 72 hours. There was no clinically meaningful increase in plasma lactate or creatinine in any patient with a normal value on enrolment. Patients receiving fluid replacement with the conservative fluid replacement algorithm were more likely to survive than historical controls in the same hospitals who had received fluid replacement guided by clinical judgement in the year prior to the study (p = 0.03), despite having more severe disease (p < 0.001). Conclusions A conservative fluid resuscitation strategy appears safe in adults hospitalised with malaria.
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Affiliation(s)
| | - Myat Kaung
- Hpa-an Hospital, Hpa-an, Kayin State, Myanmar
| | | | - Myat Phone Kyaw
- Department of Medical Research (Lower Myanmar), Yangon, Myanmar
| | - Myo Min
- Myanmar Medical Association, Yangon, Myanmar
| | | | - Nicholas M. Anstey
- Menzies School of Health Research, Charles Darwin University, Darwin, Australia
| | | | - Josh Hanson
- Menzies School of Health Research, Charles Darwin University, Darwin, Australia
- * E-mail:
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26
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Chertow JH, Alkaitis MS, Nardone G, Ikeda AK, Cunnington AJ, Okebe J, Ebonyi AO, Njie M, Correa S, Jayasooriya S, Casals-Pascual C, Billker O, Conway DJ, Walther M, Ackerman H. Plasmodium Infection Is Associated with Impaired Hepatic Dimethylarginine Dimethylaminohydrolase Activity and Disruption of Nitric Oxide Synthase Inhibitor/Substrate Homeostasis. PLoS Pathog 2015; 11:e1005119. [PMID: 26407009 PMCID: PMC4583463 DOI: 10.1371/journal.ppat.1005119] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Accepted: 07/29/2015] [Indexed: 12/04/2022] Open
Abstract
Inhibition of nitric oxide (NO) signaling may contribute to pathological activation of the vascular endothelium during severe malaria infection. Dimethylarginine dimethylaminohydrolase (DDAH) regulates endothelial NO synthesis by maintaining homeostasis between asymmetric dimethylarginine (ADMA), an endogenous NO synthase (NOS) inhibitor, and arginine, the NOS substrate. We carried out a community-based case-control study of Gambian children to determine whether ADMA and arginine homeostasis is disrupted during severe or uncomplicated malaria infections. Circulating plasma levels of ADMA and arginine were determined at initial presentation and 28 days later. Plasma ADMA/arginine ratios were elevated in children with acute severe malaria compared to 28-day follow-up values and compared to children with uncomplicated malaria or healthy children (p<0.0001 for each comparison). To test the hypothesis that DDAH1 is inactivated during Plasmodium infection, we examined DDAH1 in a mouse model of severe malaria. Plasmodium berghei ANKA infection inactivated hepatic DDAH1 via a post-transcriptional mechanism as evidenced by stable mRNA transcript number, decreased DDAH1 protein concentration, decreased enzyme activity, elevated tissue ADMA, elevated ADMA/arginine ratio in plasma, and decreased whole blood nitrite concentration. Loss of hepatic DDAH1 activity and disruption of ADMA/arginine homeostasis may contribute to severe malaria pathogenesis by inhibiting NO synthesis. During a malaria infection, the vascular endothelium becomes more adhesive, permeable, and prone to trigger blood clotting. These changes help the parasite adhere to blood vessels, but endanger the host by obstructing blood flow through small vessels. Endothelial nitric oxide (NO) would normally counteract these pathological changes, but NO signalling is diminished malaria. NO synthesis is inhibited by asymmetric dimethylarginine (ADMA), a methylated derivative of arginine that is released during normal protein turnover. We found the ratio of ADMA to arginine to be elevated in Gambian children with severe malaria, a metabolic disturbance known to inhibit NO synthesis. ADMA was associated with markers of endothelial activation and impaired tissue perfusion. In parallel experiments using mice, the enzyme responsible for metabolizing ADMA, dimethylarginine dimethylaminohydrolase (DDAH), was inactivated after infection with a rodent malaria. Based on these studies, we propose that decreased metabolism of ADMA by DDAH might contribute to the elevated ADMA/arginine ratio observed during an acute episode of malaria. Strategies to preserve or increase DDAH activity might improve NO synthesis and help to prevent the vascular manifestations of severe malaria.
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Affiliation(s)
- Jessica H. Chertow
- Laboratory of Malaria and Vector Research, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Matthew S. Alkaitis
- Laboratory of Malaria and Vector Research, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
- Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Headington Oxford, United Kingdom
| | - Glenn Nardone
- Research Technology Branch, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Allison K. Ikeda
- Laboratory of Malaria and Vector Research, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | | | | | | | | | | | | | | | - Oliver Billker
- Wellcome Trust Sanger Institute, Hinxton Cambridge, United Kingdom
| | - David J. Conway
- MRC Unit, Fajara, The Gambia
- London School of Hygiene and Tropical Medicine, Bloomsbury, London, United Kingdom
| | | | - Hans Ackerman
- Laboratory of Malaria and Vector Research, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
- * E-mail:
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27
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Yeo TW, Anstey NM. Reply to Eisenhut. J Infect Dis 2015; 212:168. [PMID: 25712978 DOI: 10.1093/infdis/jiv085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Accepted: 02/10/2015] [Indexed: 11/13/2022] Open
Affiliation(s)
- Tsin Wen Yeo
- Menzies School of Health Research and Charles Darwin University, Casuarina, Australia
| | - Nicholas M Anstey
- Menzies School of Health Research and Charles Darwin University, Casuarina, Australia
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28
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Hanson J, Lee SJ, Hossain MA, Anstey NM, Charunwatthana P, Maude RJ, Kingston HWF, Mishra SK, Mohanty S, Plewes K, Piera K, Hassan MU, Ghose A, Faiz MA, White NJ, Day NPJ, Dondorp AM. Microvascular obstruction and endothelial activation are independently associated with the clinical manifestations of severe falciparum malaria in adults: an observational study. BMC Med 2015; 13:122. [PMID: 26018532 PMCID: PMC4453275 DOI: 10.1186/s12916-015-0365-9] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Accepted: 05/12/2015] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Microvascular obstruction and endothelial dysfunction have both been linked to tissue hypoperfusion in falciparum malaria, but their relative contributions to the disease's pathogenesis and outcome are unknown. METHODS Microvascular blood flow was quantified in adults with severe falciparum malaria on their admission to hospital; plasma biomarkers of endothelial function were measured simultaneously. The relationship between these indices and the patients' clinical findings and in-hospital course was examined. RESULTS Microvascular obstruction was observed in 119/142 (84 %) patients; a median (interquartile range (IQR)) of 14.9 % (6.6-34.9 %) of capillaries were obstructed in patients that died versus 8.3 % (1.7-26.6 %) in survivors (P = 0.039). The proportion of obstructed capillaries correlated with the estimated parasite biomass (rs = 0.25, P = 0.004) and with plasma lactate (rs = 0.38, P <0.0001), the strongest predictor of death in the series. Plasma angiopoietin-2 (Ang-2) concentrations were markedly elevated suggesting widespread endothelial activation; the median (IQR) Ang-2 concentration was 21.9 ng/mL (13.4-29.4 ng/mL) in patients that died versus 14.9 ng/mL (9.8-29.3 ng/mL) in survivors (P = 0.035). Ang-2 concentrations correlated with estimated parasite biomass (rs = 0.35, P <0.001) and plasma lactate (rs = 0.37, P <0.0001). Microvascular obstruction and Ang-2 concentrations were not significantly correlated with each other (rs = 0.17, P = 0.06), but were independently associated with plasma lactate (P <0.001 and P = 0.002, respectively). CONCLUSIONS Microvascular obstruction and systemic endothelial activation are independently associated with plasma lactate, the strongest predictor of death in adults with falciparum malaria. This supports the hypothesis that the two processes make an independent contribution to the pathogenesis and clinical manifestations of the disease.
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Affiliation(s)
- Josh Hanson
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand. .,Global Health Division, Menzies School of Health Research, Darwin, Australia.
| | - Sue J Lee
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand. .,Centre for Tropical Medicine, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK.
| | - Md Amir Hossain
- Department of Medicine, Chittagong Medical College Hospital, Chittagong, Bangladesh.
| | - Nicholas M Anstey
- Global Health Division, Menzies School of Health Research, Darwin, Australia.
| | - Prakaykaew Charunwatthana
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
| | - Richard J Maude
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand. .,Centre for Tropical Medicine, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK.
| | - Hugh W F Kingston
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand. .,Global Health Division, Menzies School of Health Research, Darwin, Australia.
| | - Saroj K Mishra
- Department of Medicine, Ispat Hospital, Rourkela, Orissa, India.
| | - Sanjib Mohanty
- Department of Medicine, Ispat Hospital, Rourkela, Orissa, India.
| | - Katherine Plewes
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
| | - Kim Piera
- Global Health Division, Menzies School of Health Research, Darwin, Australia.
| | - Mahtab U Hassan
- Department of Medicine, Chittagong Medical College Hospital, Chittagong, Bangladesh.
| | - Aniruddha Ghose
- Department of Medicine, Chittagong Medical College Hospital, Chittagong, Bangladesh.
| | - M Abul Faiz
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand. .,Centre for Specialized Care and Research, Chittagong, Bangladesh. .,Dev Care Foundation, Dhaka, Bangladesh.
| | - Nicholas J White
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand. .,Centre for Tropical Medicine, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK.
| | - Nicholas P J Day
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand. .,Centre for Tropical Medicine, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK.
| | - Arjen M Dondorp
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand. .,Centre for Tropical Medicine, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK.
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29
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Yeo TW, Lampah DA, Kenangalem E, Tjitra E, Price RN, Weinberg JB, Hyland K, Granger DL, Anstey NM. Impaired systemic tetrahydrobiopterin bioavailability and increased dihydrobiopterin in adult falciparum malaria: association with disease severity, impaired microvascular function and increased endothelial activation. PLoS Pathog 2015; 11:e1004667. [PMID: 25764397 PMCID: PMC4357386 DOI: 10.1371/journal.ppat.1004667] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Accepted: 01/07/2015] [Indexed: 12/22/2022] Open
Abstract
Tetrahydrobiopterin (BH₄) is a co-factor required for catalytic activity of nitric oxide synthase (NOS) and amino acid-monooxygenases, including phenylalanine hydroxylase. BH4 is unstable: during oxidative stress it is non-enzymatically oxidized to dihydrobiopterin (BH₂), which inhibits NOS. Depending on BH₄ availability, NOS oscillates between NO synthase and NADPH oxidase: as the BH₄/BH₂ ratio decreases, NO production falls and is replaced by superoxide. In African children and Asian adults with severe malaria, NO bioavailability decreases and plasma phenylalanine increases, together suggesting possible BH₄ deficiency. The primary three biopterin metabolites (BH₄, BH₂ and B₀ [biopterin]) and their association with disease severity have not been assessed in falciparum malaria. We measured pterin metabolites in urine of adults with severe falciparum malaria (SM; n=12), moderately-severe malaria (MSM, n=17), severe sepsis (SS; n=5) and healthy subjects (HC; n=20) as controls. In SM, urinary BH₄ was decreased (median 0.16 ¼mol/mmol creatinine) compared to MSM (median 0.27), SS (median 0.54), and HC (median 0.34)]; p<0.001. Conversely, BH₂ was increased in SM (median 0.91 ¼mol/mmol creatinine), compared to MSM (median 0.67), SS (median 0.39), and HC (median 0.52); p<0.001, suggesting increased oxidative stress and insufficient recycling of BH2 back to BH4 in severe malaria. Overall, the median BH₄/BH₂ ratio was lowest in SM [0.18 (IQR: 0.04-0.32)] compared to MSM (0.45, IQR 0.27-61), SS (1.03; IQR 0.54-2.38) and controls (0.66; IQR 0.43-1.07); p<0.001. In malaria, a lower BH₄/BH₂ ratio correlated with decreased microvascular reactivity (r=0.41; p=0.03) and increased ICAM-1 (r=-0.52; p=0.005). Decreased BH4 and increased BH₂ in severe malaria (but not in severe sepsis) uncouples NOS, leading to impaired NO bioavailability and potentially increased oxidative stress. Adjunctive therapy to regenerate BH4 may have a role in improving NO bioavailability and microvascular perfusion in severe falciparum malaria.
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Affiliation(s)
- Tsin W. Yeo
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Northern Territory, Australia
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore
- Institute of Infectious Disease and Epidemiology, Tan Tock Seng Hospital, Singapore
| | - Daniel A. Lampah
- Menzies School of Health Research-National Institute of Health Research and Development Research Program, and District Ministry of Health, Timika, Papua, Indonesia
| | - Enny Kenangalem
- Menzies School of Health Research-National Institute of Health Research and Development Research Program, and District Ministry of Health, Timika, Papua, Indonesia
| | - Emiliana Tjitra
- National Institute of Health Research and Development, Jakarta, Indonesia
| | - Ric N. Price
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Northern Territory, Australia
- Centre for Tropical Medicine, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, United Kingdom
| | - J. Brice Weinberg
- Duke University and VA Medical Centers, Durham, North Carolina, United States of America
| | - Keith Hyland
- Medical Neurogenetics LLC, Atlanta, Georgia, United States of America
| | - Donald L. Granger
- Division of Infectious Diseases, University of Utah and Veterans Affairs Medical Center, Salt Lake City, Utah, United States of America
| | - Nicholas M. Anstey
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Northern Territory, Australia
- Division of Medicine, Royal Darwin Hospital, Darwin, Northern Territory, Australia
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30
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Rubach MP, Mukemba J, Florence S, Lopansri BK, Hyland K, Volkheimer AD, Yeo TW, Anstey NM, Weinberg JB, Mwaikambo ED, Granger DL. Impaired systemic tetrahydrobiopterin bioavailability and increased oxidized biopterins in pediatric falciparum malaria: association with disease severity. PLoS Pathog 2015; 11:e1004655. [PMID: 25764173 PMCID: PMC4357384 DOI: 10.1371/journal.ppat.1004655] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Accepted: 01/05/2015] [Indexed: 12/17/2022] Open
Abstract
Decreased bioavailability of nitric oxide (NO) is a major contributor to the pathophysiology of severe falciparum malaria. Tetrahydrobiopterin (BH4) is an enzyme cofactor required for NO synthesis from L-arginine. We hypothesized that systemic levels of BH₄ would be decreased in children with cerebral malaria, contributing to low NO bioavailability. In an observational study in Tanzania, we measured urine levels of biopterin in its various redox states (fully reduced [BH₄] and the oxidized metabolites, dihydrobiopterin [BH₂] and biopterin [B₀]) in children with uncomplicated malaria (UM, n = 55), cerebral malaria (CM, n = 45), non-malaria central nervous system conditions (NMC, n = 48), and in 111 healthy controls (HC). Median urine BH4 concentration in CM (1.10 [IQR:0.55-2.18] μmol/mmol creatinine) was significantly lower compared to each of the other three groups - UM (2.10 [IQR:1.32-3.14];p<0.001), NMC (1.52 [IQR:1.01-2.71];p = 0.002), and HC (1.60 [IQR:1.15-2.23];p = 0.005). Oxidized biopterins were increased, and the BH4:BH2 ratio markedly decreased in CM. In a multivariate logistic regression model, each Log10-unit decrease in urine BH4 was independently associated with a 3.85-fold (95% CI:1.89-7.61) increase in odds of CM (p<0.001). Low systemic BH4 levels and increased oxidized biopterins contribute to the low NO bioavailability observed in CM. Adjunctive therapy to regenerate BH4 may have a role in improving NO bioavailability and microvascular perfusion in severe falciparum malaria.
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Affiliation(s)
- Matthew P. Rubach
- Department of Medicine, Duke University and VA Medical Centers, Durham, North Carolina, United States of America
| | - Jackson Mukemba
- Department of Pediatrics, Hubert Kairuki Memorial University, Dar es Salaam, United Republic of Tanzania
| | - Salvatore Florence
- Department of Pediatrics, Hubert Kairuki Memorial University, Dar es Salaam, United Republic of Tanzania
| | - Bert K. Lopansri
- Department of Medicine, Intermountain Healthcare, Salt Lake City, Utah, United States of America
- Department of Medicine, University of Utah School of Medicine and VA Medical Center, Salt Lake City, Utah, United States of America
| | - Keith Hyland
- Neurochemistry Division, Medical Neurogenetics, Atlanta, Georgia, United States of America
| | - Alicia D. Volkheimer
- Department of Medicine, Duke University and VA Medical Centers, Durham, North Carolina, United States of America
| | - Tsin W. Yeo
- Global and Tropical Health Division, Menzies School for Health Research and Charles Darwin University, Darwin, Australia
- Division of Medicine, Royal Darwin Hospital, Darwin, Northern Territory, Australia
- Department of Medicine, Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore
| | - Nicholas M. Anstey
- Global and Tropical Health Division, Menzies School for Health Research and Charles Darwin University, Darwin, Australia
- Division of Medicine, Royal Darwin Hospital, Darwin, Northern Territory, Australia
| | - J. Brice Weinberg
- Department of Medicine, Duke University and VA Medical Centers, Durham, North Carolina, United States of America
| | - Esther D. Mwaikambo
- Department of Pediatrics, Hubert Kairuki Memorial University, Dar es Salaam, United Republic of Tanzania
| | - Donald L. Granger
- Department of Medicine, University of Utah School of Medicine and VA Medical Center, Salt Lake City, Utah, United States of America
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Barber BE, William T, Grigg MJ, Parameswaran U, Piera KA, Price RN, Yeo TW, Anstey NM. Parasite biomass-related inflammation, endothelial activation, microvascular dysfunction and disease severity in vivax malaria. PLoS Pathog 2015; 11:e1004558. [PMID: 25569250 PMCID: PMC4287532 DOI: 10.1371/journal.ppat.1004558] [Citation(s) in RCA: 108] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Accepted: 11/06/2014] [Indexed: 12/05/2022] Open
Abstract
Plasmodium vivax can cause severe malaria, however its pathogenesis is poorly understood. In contrast to P. falciparum, circulating vivax parasitemia is low, with minimal apparent sequestration in endothelium-lined microvasculature, and pathogenesis thought unrelated to parasite biomass. However, the relationships between vivax disease-severity and total parasite biomass, endothelial autocrine activation and microvascular dysfunction are unknown. We measured circulating parasitemia and markers of total parasite biomass (plasma parasite lactate dehydrogenase [pLDH] and PvLDH) in adults with severe (n = 9) and non-severe (n = 53) vivax malaria, and examined relationships with disease-severity, endothelial activation, and microvascular function. Healthy controls and adults with non-severe and severe falciparum malaria were enrolled for comparison. Median peripheral parasitemia, PvLDH and pLDH were 2.4-fold, 3.7-fold and 6.9-fold higher in severe compared to non-severe vivax malaria (p = 0.02, p = 0.02 and p = 0.015, respectively), suggesting that, as in falciparum malaria, peripheral P. vivax parasitemia underestimates total parasite biomass, particularly in severe disease. P. vivax schizonts were under-represented in peripheral blood. Severe vivax malaria was associated with increased angiopoietin-2 and impaired microvascular reactivity. Peripheral vivax parasitemia correlated with endothelial activation (angiopoietin-2, von-Willebrand-Factor [VWF], E-selectin), whereas markers of total vivax biomass correlated only with systemic inflammation (IL-6, IL-10). Activity of the VWF-cleaving-protease, ADAMTS13, was deficient in proportion to endothelial activation, IL-6, thrombocytopenia and vivax disease-severity, and associated with impaired microvascular reactivity in severe disease. Impaired microvascular reactivity correlated with lactate in severe vivax malaria. Findings suggest that tissue accumulation of P. vivax may occur, with the hidden biomass greatest in severe disease and capable of mediating systemic inflammatory pathology. The lack of association between total parasite biomass and endothelial activation is consistent with accumulation in parts of the circulation devoid of endothelium. Endothelial activation, associated with circulating parasites, and systemic inflammation may contribute to pathology in vivax malaria, with microvascular dysfunction likely contributing to impaired tissue perfusion.
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Affiliation(s)
- Bridget E. Barber
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Northern Territory, Australia
- Department of Infectious Diseases, Queen Elizabeth Hospital, Sabah, Malaysia
- Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, Kota Kinabalu, Sabah, Malaysia
| | - Timothy William
- Department of Infectious Diseases, Queen Elizabeth Hospital, Sabah, Malaysia
- Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, Kota Kinabalu, Sabah, Malaysia
| | - Matthew J. Grigg
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Northern Territory, Australia
- Department of Infectious Diseases, Queen Elizabeth Hospital, Sabah, Malaysia
- Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, Kota Kinabalu, Sabah, Malaysia
| | - Uma Parameswaran
- Department of Infectious Diseases, Queen Elizabeth Hospital, Sabah, Malaysia
- Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, Kota Kinabalu, Sabah, Malaysia
| | - Kim A. Piera
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Northern Territory, Australia
| | - Ric N. Price
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Northern Territory, Australia
- Centre for Tropical Medicine, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, United Kingdom
| | - Tsin W. Yeo
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Northern Territory, Australia
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore
- Insitute of Infectious Disease and Epidemiology, Tan Tock Seng Hospital, Singapore
| | - Nicholas M. Anstey
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Northern Territory, Australia
- Department of Infectious Diseases, Royal Darwin Hospital, Darwin, Northern Territory, Australia
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Yeo TW, Lampah DA, Kenangalem E, Tjitra E, Weinberg JB, Granger DL, Price RN, Anstey NM. Decreased endothelial nitric oxide bioavailability, impaired microvascular function, and increased tissue oxygen consumption in children with falciparum malaria. J Infect Dis 2014; 210:1627-32. [PMID: 24879801 DOI: 10.1093/infdis/jiu308] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Endothelial nitric oxide (NO) bioavailability, microvascular function, and host oxygen consumption have not been assessed in pediatric malaria. We measured NO-dependent endothelial function by using peripheral artery tonometry to determine the reactive hyperemia index (RHI), and microvascular function and oxygen consumption (VO2) using near infrared resonance spectroscopy in 13 Indonesian children with severe falciparum malaria and 15 with moderately severe falciparum malaria. Compared with 19 controls, children with severe malaria and those with moderately severe malaria had lower RHIs (P = .03); 12% and 8% lower microvascular function, respectively (P = .03); and 29% and 25% higher VO2, respectively. RHIs correlated with microvascular function in all children with malaria (P < .001) and all with severe malaria (P < .001). Children with malaria have decreased endothelial and microvascular function and increased oxygen consumption, likely contributing to the pathogenesis of the disease.
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Affiliation(s)
- Tsin W Yeo
- Global Health Division, Menzies School of Health Research and Charles Darwin University Lee Kong Chian School of Medicine, Nanyang Technological University Institute of Infectious Disease and Epidemiology, Tan Tock Seng Hospital, Singapore
| | - Daniel A Lampah
- District Ministry of Health, Menzies School of Health Research-National Institute of Health Research and Development Research Program, Timika
| | - Enny Kenangalem
- District Ministry of Health, Menzies School of Health Research-National Institute of Health Research and Development Research Program, Timika
| | - Emiliana Tjitra
- National Institute of Health Research and Development, Jakarta, Indonesia
| | - J Brice Weinberg
- Division of Hematology, Department of Medicine, School of Medicine, Duke University Division of Hematology-Oncology, Durham VA Medical Center, North Carolina
| | - Donald L Granger
- Division of Infectious Diseases, Department of Internal Medicine, University of Utah School of Medicine, Division of Infectious Diseases, Department of Internal Medicine, VA Salt Lake Health Care System, Salt Lake City, Utah
| | - Ric N Price
- Global Health Division, Menzies School of Health Research and Charles Darwin University Division of Medicine, Royal Darwin Hospital, Australia Centre for Vaccinology and Tropical Medicine, Nuffield Department of Clinical Medicine, Churchill Hospital, Oxford, United Kingdom
| | - Nicholas M Anstey
- Global Health Division, Menzies School of Health Research and Charles Darwin University Division of Medicine, Royal Darwin Hospital, Australia
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Bachmann J, Burté F, Pramana S, Conte I, Brown BJ, Orimadegun AE, Ajetunmobi WA, Afolabi NK, Akinkunmi F, Omokhodion S, Akinbami FO, Shokunbi WA, Kampf C, Pawitan Y, Uhlén M, Sodeinde O, Schwenk JM, Wahlgren M, Fernandez-Reyes D, Nilsson P. Affinity proteomics reveals elevated muscle proteins in plasma of children with cerebral malaria. PLoS Pathog 2014; 10:e1004038. [PMID: 24743550 PMCID: PMC3990714 DOI: 10.1371/journal.ppat.1004038] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Accepted: 02/06/2014] [Indexed: 01/21/2023] Open
Abstract
Systemic inflammation and sequestration of parasitized erythrocytes are central processes in the pathophysiology of severe Plasmodium falciparum childhood malaria. However, it is still not understood why some children are more at risks to develop malaria complications than others. To identify human proteins in plasma related to childhood malaria syndromes, multiplex antibody suspension bead arrays were employed. Out of the 1,015 proteins analyzed in plasma from more than 700 children, 41 differed between malaria infected children and community controls, whereas 13 discriminated uncomplicated malaria from severe malaria syndromes. Markers of oxidative stress were found related to severe malaria anemia while markers of endothelial activation, platelet adhesion and muscular damage were identified in relation to children with cerebral malaria. These findings suggest the presence of generalized vascular inflammation, vascular wall modulations, activation of endothelium and unbalanced glucose metabolism in severe malaria. The increased levels of specific muscle proteins in plasma implicate potential muscle damage and microvasculature lesions during the course of cerebral malaria. Why do some malaria-infected children develop severe and lethal forms of the disease, while others only have mild forms? In order to try to find potential answers or clues to this question, we have here analyzed more than 1,000 different human proteins in the blood of more than 500 malaria-infected children from Ibadan in Nigeria, a holoendemic malaria region. We identified several proteins that were present at higher levels in the blood from the children that developed severe malaria in comparison to those that did not. Some of the most interesting identified proteins were muscle specific proteins, which indicate that damaged muscles could be a discriminatory pathologic event in cerebral malaria compared to other malaria cases. These findings will hopefully lead to an increased understanding of the disease and may contribute to the development of clinical algorithms that could predict which children are more at risks to severe malaria. This in turn will be of high value in the management of these children in already overloaded tertiary-care health facilities in urban large densely-populated sub-Saharan cities with holoendemic malaria such as in the case of Ibadan and Lagos.
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Affiliation(s)
- Julie Bachmann
- SciLifeLab Stockholm, School of Biotechnology, KTH-Royal Institute of Technology, Stockholm, Sweden
| | - Florence Burté
- Division of Parasitology, Medical Research Council National Institute for Medical Research, London, United Kingdom
| | - Setia Pramana
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
| | - Ianina Conte
- Division of Parasitology, Medical Research Council National Institute for Medical Research, London, United Kingdom
| | - Biobele J. Brown
- Department of Paediatrics, College of Medicine, University of Ibadan, University College Hospital, Ibadan, Nigeria
- Department of Haematology, College of Medicine, University of Ibadan, University College Hospital, Ibadan, Nigeria
- Childhood Malaria Research Group, University College Hospital, Ibadan, Nigeria
| | - Adebola E. Orimadegun
- Department of Paediatrics, College of Medicine, University of Ibadan, University College Hospital, Ibadan, Nigeria
| | - Wasiu A. Ajetunmobi
- Department of Paediatrics, College of Medicine, University of Ibadan, University College Hospital, Ibadan, Nigeria
| | - Nathaniel K. Afolabi
- Department of Paediatrics, College of Medicine, University of Ibadan, University College Hospital, Ibadan, Nigeria
| | - Francis Akinkunmi
- Department of Paediatrics, College of Medicine, University of Ibadan, University College Hospital, Ibadan, Nigeria
| | - Samuel Omokhodion
- Department of Paediatrics, College of Medicine, University of Ibadan, University College Hospital, Ibadan, Nigeria
- Childhood Malaria Research Group, University College Hospital, Ibadan, Nigeria
| | - Felix O. Akinbami
- Department of Paediatrics, College of Medicine, University of Ibadan, University College Hospital, Ibadan, Nigeria
- Childhood Malaria Research Group, University College Hospital, Ibadan, Nigeria
| | - Wuraola A. Shokunbi
- Department of Haematology, College of Medicine, University of Ibadan, University College Hospital, Ibadan, Nigeria
- Childhood Malaria Research Group, University College Hospital, Ibadan, Nigeria
| | - Caroline Kampf
- Department of Immunology, Genetics and Pathology, Rudbeck Laboratory, Uppsala University, Uppsala, Sweden
| | - Yudi Pawitan
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
| | - Mathias Uhlén
- SciLifeLab Stockholm, School of Biotechnology, KTH-Royal Institute of Technology, Stockholm, Sweden
| | - Olugbemiro Sodeinde
- Division of Parasitology, Medical Research Council National Institute for Medical Research, London, United Kingdom
- Department of Paediatrics, College of Medicine, University of Ibadan, University College Hospital, Ibadan, Nigeria
- Department of Haematology, College of Medicine, University of Ibadan, University College Hospital, Ibadan, Nigeria
- Childhood Malaria Research Group, University College Hospital, Ibadan, Nigeria
| | - Jochen M. Schwenk
- SciLifeLab Stockholm, School of Biotechnology, KTH-Royal Institute of Technology, Stockholm, Sweden
| | - Mats Wahlgren
- Department of Microbiology, Tumour and Cell Biology, Karolinska Institutet, Stockholm, Sweden
- * E-mail: (MW); (DFR); (PN)
| | - Delmiro Fernandez-Reyes
- Division of Parasitology, Medical Research Council National Institute for Medical Research, London, United Kingdom
- Department of Paediatrics, College of Medicine, University of Ibadan, University College Hospital, Ibadan, Nigeria
- Department of Haematology, College of Medicine, University of Ibadan, University College Hospital, Ibadan, Nigeria
- Childhood Malaria Research Group, University College Hospital, Ibadan, Nigeria
- Brighton & Sussex Medical School, Sussex University, Brighton, United Kingdom
- * E-mail: (MW); (DFR); (PN)
| | - Peter Nilsson
- SciLifeLab Stockholm, School of Biotechnology, KTH-Royal Institute of Technology, Stockholm, Sweden
- * E-mail: (MW); (DFR); (PN)
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Fernandez-Arias C, Arias CF, Rodriguez A. Is malarial anaemia homologous to neocytolysis after altitude acclimatisation? Int J Parasitol 2014; 44:19-22. [DOI: 10.1016/j.ijpara.2013.06.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2013] [Revised: 06/24/2013] [Accepted: 06/25/2013] [Indexed: 01/01/2023]
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Cunnington AJ, Riley EM, Walther M. Stuck in a rut? Reconsidering the role of parasite sequestration in severe malaria syndromes. Trends Parasitol 2013; 29:585-92. [PMID: 24210256 PMCID: PMC3880783 DOI: 10.1016/j.pt.2013.10.004] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Revised: 09/30/2013] [Accepted: 10/07/2013] [Indexed: 12/20/2022]
Abstract
Severe malaria defines individuals at increased risk of death from their infection. Proposed pathogenic mechanisms include parasite sequestration, inflammation, and endothelial dysfunction. Severe malaria is not a single entity, manifesting with distinct syndromes such as severe anemia, severe respiratory distress or coma, each characterized by differences in epidemiology, underlying biology, and risk of death. The relative contribution of the various pathogenic mechanisms may differ between syndromes, and this is supported by accumulating evidence, which challenges sequestration as the initiating event. Here we propose that high parasite biomass is the common initiating feature, but subtle variations in the interaction between the host and parasite exist, and understanding these differences may be crucial to improve outcomes in patients with severe malaria.
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Yeo TW, Lampah DA, Rooslamiati I, Gitawati R, Tjitra E, Kenangalem E, Price RN, Duffull SB, Anstey NM. A randomized pilot study of L-arginine infusion in severe falciparum malaria: preliminary safety, efficacy and pharmacokinetics. PLoS One 2013; 8:e69587. [PMID: 23922746 PMCID: PMC3726665 DOI: 10.1371/journal.pone.0069587] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2012] [Accepted: 06/10/2013] [Indexed: 12/11/2022] Open
Abstract
Background Decreased nitric oxide (NO) and hypoargininemia are associated with severe falciparum malaria and may contribute to severe disease. Intravenous L-arginine increases endothelial NO in moderately-severe malaria (MSM) without adverse effects. The safety, efficacy and pharmacokinetics of L-arginine or other agents to improve NO bioavailability in severe malaria have not been assessed. Methods In an open-label pilot study of L-arginine in adults with severe malaria (ARGISM-1 Study), patients were randomized to 12 g L-arginine hydrochloride or saline over 8 hours together with intravenous artesunate. Vital signs, selected biochemical measures (including blood lactate and L-arginine) and endothelial NO bioavailability (using reactive hyperemia peripheral arterial tonometry [RH-PAT]) were assessed serially. Pharmacokinetic analyses of L-arginine concentrations were performed using NONMEM. Results Six patients received L-arginine and two saline infusions. There were no deaths in either group. There were no changes in mean systolic (SBP) and diastolic blood pressure (DBP) or other vital signs with L-arginine, although a transient but clinically unimportant mean maximal decrease in SBP of 14 mmHg was noted. No significant changes in mean potassium, glucose, bicarbonate, or pH were seen, with transient mean maximal increases in plasma potassium of 0.3 mmol/L, and mean maximal decreases in blood glucose of 0.8 mmol/L and bicarbonate of 2.3 mEq/L following L-arginine administration. There was no effect on lactate clearance or RH-PAT index. Pharmacokinetic modelling (n = 4) showed L-arginine concentrations 40% lower than predicted from models developed in MSM. Conclusion In the first clinical trial of an adjunctive treatment aimed at increasing NO bioavailability in severe malaria, L-arginine infused at 12 g over 8 hours was safe, but did not improve lactate clearance or endothelial NO bioavailability. Future studies may require increased doses of L-arginine. Trial Registration ClinicalTrials.gov NTC00616304
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Affiliation(s)
- Tsin W Yeo
- Global Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia.
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Yeo TW, Lampah DA, Kenangalem E, Tjitra E, Price RN, Anstey NM. Increased carboxyhemoglobin in adult falciparum malaria is associated with disease severity and mortality. J Infect Dis 2013; 208:813-7. [PMID: 23852587 DOI: 10.1093/infdis/jit253] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Heme oxygenase 1 expression is increased in pediatric patients with malaria. The carboxyhemoglobin level (a measure of heme oxygenase 1 activity) has not been assessed in adult patients with malaria. Results of pulse co-oximetry revealed that the mean carboxyhemoglobin level was elevated in 29 Indonesian adults with severe falciparum malaria (10%; 95% confidence interval [CI], 8%-13%) and in 20 with severe sepsis (8%; 95% CI, 5%-12%), compared with the mean levels in 32 patients with moderately severe malaria (7%; 95% CI, 5%-8%) and 36 controls (3.6%; 95% CI, 3%-5%; P < .001). An increased carboxyhemoglobin level was associated with an increased odds of death among patients with severe malaria (odds ratio, 1.2 per percentage point increase; 95% CI, 1.02-1.5). While also associated with severity and fatality, methemoglobin was only modestly increased in patients with severe malaria. Increased carboxyhemoglobin levels during severe malaria and sepsis may exacerbate organ dysfunction by reducing oxygen carriage and cautions against the use of adjunctive CO therapy, which was proposed on the basis of mouse models.
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Affiliation(s)
- Tsin W Yeo
- Global Health Division, Menzies School of Health Research and Charles Darwin University, Royal Darwin Hospital, Darwin, Australia.
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Cunnington AJ, Bretscher MT, Nogaro SI, Riley EM, Walther M. Comparison of parasite sequestration in uncomplicated and severe childhood Plasmodium falciparum malaria. J Infect 2013; 67:220-30. [PMID: 23623771 PMCID: PMC3744804 DOI: 10.1016/j.jinf.2013.04.013] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2013] [Revised: 04/13/2013] [Accepted: 04/15/2013] [Indexed: 12/31/2022]
Abstract
Objectives To determine whether sequestration of parasitized red blood cells differs between children with uncomplicated and severe Plasmodium falciparum malaria. Methods We quantified circulating-, total- and sequestered-parasite biomass, using a mathematical model based on plasma concentration of P. falciparum histidine rich protein 2, in Gambian children with severe (n = 127) and uncomplicated (n = 169) malaria. Results Circulating- and total-, but not sequestered-, parasite biomass estimates were significantly greater in children with severe malaria than in those with uncomplicated malaria. Sequestered biomass estimates in children with hyperlactataemia or prostration were similar to those in uncomplicated malaria, whereas sequestered biomass was higher in patients with severe anaemia, and showed a trend to higher values in cerebral malaria and fatal cases. Blood lactate concentration correlated with circulating- and total-, but not sequestered parasite biomass. These findings were robust after controlling for age, prior antimalarial treatment and clonality of infection, and over a realistic range of variation in model parameters. Conclusion Extensive sequestration is not a uniform requirement for severe paediatric malaria. The pathophysiology of hyperlactataemia and prostration appears to be unrelated to sequestered parasite biomass. Different mechanisms may underlie different severe malaria syndromes, and different therapeutic strategies may be required to improve survival.
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Affiliation(s)
- Aubrey J Cunnington
- Department of Immunology and Infection, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
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