1
|
Ortiz-Martínez Y, Kouamé MG, Bongomin F, Lakoh S, Henao-Martínez AF. Human African Trypanosomiasis (Sleeping Sickness)-Epidemiology, Clinical Manifestations, Diagnosis, Treatment, and Prevention. CURRENT TROPICAL MEDICINE REPORTS 2023; 10:222-234. [PMID: 38939748 PMCID: PMC11210952 DOI: 10.1007/s40475-023-00304-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/13/2023] [Indexed: 06/29/2024]
Abstract
Purpose of Review Human African Trypanosomiasis (HAT), also known as sleeping sickness, is a vector-borne parasitic neglected tropical disease (NTD) endemic in sub-Saharan Africa. This review aims to enhance our understanding of HAT and provide valuable insights to combat this significant public health issue by synthesizing the latest research and evidence. Recent Findings HAT has reached a historical < 1000 cases in 2018. In patients without neurologic symptoms and signs, the likelihood of a severe meningoencephalitic stage is deemed low, obviating the need for a lumbar puncture to guide treatment decisions using fexinidazole. Summary Both forms of the disease, gambiense HAT (gHAT) and rhodesiense HAT (rHAT), have specific epidemiology, risk factors, diagnosis, and treatment. Disease management still requires a high index of suspicion, infectious disease expertise, and specialized medical care. Essential stakeholders in health policy are critical to accomplishing the elimination goals of the NTD roadmap for 2021-2030.
Collapse
Affiliation(s)
- Yeimer Ortiz-Martínez
- Department of Internal Medicine, Universidad Industrial de Santander, Bucaramanga, Colombia
| | | | - Felix Bongomin
- Department of Medical Microbiology and Immunology, Faculty of Medicine, Gulu University, Gulu, Uganda
| | - Sulaiman Lakoh
- College of Medicine and Allied Health Sciences, University of Sierra Leone, Freetown, Sierra Leone
| | - Andrés F. Henao-Martínez
- Division of Infectious Diseases, Department of Medicine, University of Colorado, Anschutz Medical Campus, 12700 E. 19th Avenue, Mail Stop B168, Aurora, CO 80045, USA
| |
Collapse
|
2
|
Li YN, Shi X, Sun D, Han S, Zou Y, Wang L, Yang L, Li Y, Shi Y, Guo J, O'Driscoll CM. Delivery of melarsoprol using folate-targeted PEGylated cyclodextrin-based nanoparticles for hepatocellular carcinoma. Int J Pharm 2023; 636:122791. [PMID: 36863541 DOI: 10.1016/j.ijpharm.2023.122791] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Revised: 01/22/2023] [Accepted: 02/26/2023] [Indexed: 03/04/2023]
Abstract
Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer, and has become one of the most lethal malignancies in the world. Although chemotherapy remains a cornerstone of cancer therapy, the number of chemotherapeutic drugs approved for HCC is low, and emerging therapeutics are needed. Melarsoprol (MEL) is an arsenic-containing drug, and has been applied in the treatment of human African trypanosomiasis at the late stage. In this study, the potential of MEL for HCC therapy was investigated for the first time using in vitro and in vivo experimental approaches. A folate-targeted polyethylene glycol-modified amphiphilic cyclodextrin nanoparticle was developed for safe, efficient and specific delivery of MEL. Consequently, the targeted nanoformulation achieved cell-specific uptake, cytotoxicity, apoptosis and migration inhibition in HCC cells. Furthermore, the targeted nanoformulation significantly prolonged the survival of mice with orthotopic tumor, without causing toxic signs. This study indicates the potential of the targeted nanoformulation as an emerging chemotherapy option for treating HCC.
Collapse
Affiliation(s)
- Ya-Nan Li
- Department of Pediatrics, The First Hospital of Jilin University, Changchun 130021, China
| | - Xiaoju Shi
- Department of Hepatobiliary and Pancreatic Surgery, The First Hospital of Jilin University, Changchun 130021, China
| | - Dandan Sun
- School of Pharmaceutical Sciences, Jilin University, Changchun 130021, China
| | - Shulan Han
- School of Pharmaceutical Sciences, Jilin University, Changchun 130021, China
| | - Yifang Zou
- School of Pharmaceutical Sciences, Jilin University, Changchun 130021, China
| | - Lingzhi Wang
- School of Pharmaceutical Sciences, Jilin University, Changchun 130021, China
| | - Leilei Yang
- School of Pharmaceutical Sciences, Jilin University, Changchun 130021, China
| | - Yutong Li
- School of Pharmaceutical Sciences, Jilin University, Changchun 130021, China
| | - Ying Shi
- Department of Hepatology, The First Hospital of Jilin University, Changchun 130021, China.
| | - Jianfeng Guo
- School of Pharmaceutical Sciences, Jilin University, Changchun 130021, China.
| | - Caitriona M O'Driscoll
- Pharmacodelivery Group, School of Pharmacy, University College Cork, Cork T12 YN60, Ireland
| |
Collapse
|
3
|
Idro R, Ogwang R, Barragan A, Raimondo JV, Masocha W. Neuroimmunology of Common Parasitic Infections in Africa. Front Immunol 2022; 13:791488. [PMID: 35222377 PMCID: PMC8866860 DOI: 10.3389/fimmu.2022.791488] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Accepted: 01/18/2022] [Indexed: 11/13/2022] Open
Abstract
Parasitic infections of the central nervous system are an important cause of morbidity and mortality in Africa. The neurological, cognitive, and psychiatric sequelae of these infections result from a complex interplay between the parasites and the host inflammatory response. Here we review some of the diseases caused by selected parasitic organisms known to infect the nervous system including Plasmodium falciparum, Toxoplasma gondii, Trypanosoma brucei spp., and Taenia solium species. For each parasite, we describe the geographical distribution, prevalence, life cycle, and typical clinical symptoms of infection and pathogenesis. We pay particular attention to how the parasites infect the brain and the interaction between each organism and the host immune system. We describe how an understanding of these processes may guide optimal diagnostic and therapeutic strategies to treat these disorders. Finally, we highlight current gaps in our understanding of disease pathophysiology and call for increased interrogation of these often-neglected disorders of the nervous system.
Collapse
Affiliation(s)
- Richard Idro
- College of Health Sciences, Makerere University, Kampala, Uganda.,Centre of Tropical Neuroscience, Kitgum, Uganda.,Nuffield Department of Medicine, Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, United Kingdom
| | - Rodney Ogwang
- College of Health Sciences, Makerere University, Kampala, Uganda.,Centre of Tropical Neuroscience, Kitgum, Uganda.,Kenya Medical Research Institute (KEMRI) - Wellcome Trust Research Programme, Nairobi, Kenya
| | - Antonio Barragan
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
| | - Joseph Valentino Raimondo
- Division of Cell Biology, Department of Human Biology, Neuroscience Institute and Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Willias Masocha
- Department of Pharmacology and Therapeutics, Faculty of Pharmacy, Kuwait University, Safat, Kuwait
| |
Collapse
|
4
|
Qureshi IA, Saini M, Are S. Pyridoxal Kinase of Disease-causing Human Parasites: Structural and
Functional Insights to Understand its Role in Drug Discovery. Curr Protein Pept Sci 2022; 23:271-289. [DOI: 10.2174/1389203723666220519155025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Revised: 03/14/2022] [Accepted: 04/06/2022] [Indexed: 11/22/2022]
Abstract
Abstract:
Human parasites cause several diseased conditions with high morbidity and mortality in a
large section of the population residing in various geographical areas. Nearly three billion people suffer
from either one or many parasitic infections globally, with almost one million deaths annually. In spite
of extensive research and advancement in the medical field, no effective vaccine is available against
prominent human parasitic diseases that necessitate identification of novel targets for designing specific
inhibitors. Vitamin B6 is an important ubiquitous co-enzyme that participates in several biological processes
and plays an important role in scavenging ROS (reactive oxygen species) along with providing
resistance to oxidative stress. Moreover, the absence of the de novo vitamin B6 biosynthetic pathway in
human parasites makes this pathway indispensable for the survival of these pathogens. Pyridoxal kinase
(PdxK) is a crucial enzyme for vitamin B6 salvage pathway and participates in the process of vitamers
B6 phosphorylation. Since the parasites are dependent on pyridoxal kinase for their survival and infectivity
to the respective hosts, it is considered a promising candidate for drug discovery. The detailed
structural analysis of PdxK from disease-causing parasites has provided insights into the catalytic
mechanism of this enzyme as well as significant differences from their human counterpart. Simultaneously,
structure-based studies have identified small lead molecules that can be exploited for drug discovery
against protozoan parasites. The present review provides structural and functional highlights of
pyridoxal kinase for its implication in developing novel and potent therapeutics to combat fatal parasitic
diseases.
Collapse
Affiliation(s)
- Insaf Ahmed Qureshi
- Department of Biotechnology & Bioinformatics, School of Life Sciences, University of Hyderabad, Prof. C.R. Rao
Road, Hyderabad 500046, India
| | - Mayank Saini
- Department of Biotechnology & Bioinformatics, School of Life Sciences, University of Hyderabad, Prof. C.R. Rao
Road, Hyderabad 500046, India
| | - Sayanna Are
- Department of Biotechnology & Bioinformatics, School of Life Sciences, University of Hyderabad, Prof. C.R. Rao
Road, Hyderabad 500046, India
| |
Collapse
|
5
|
Mudji J, Künzli E, Molyneux D, Blum J. Long-term sequelae of congenital gambiense human African trypanosomiasis. Trans R Soc Trop Med Hyg 2021; 115:932-936. [PMID: 34051702 DOI: 10.1093/trstmh/trab082] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Revised: 04/16/2021] [Accepted: 05/26/2021] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND The clinical presentation of gambiense human African trypanosomias (gHAT) is generally considered to be the same among children and adults. In general, when describing the clinical presentation of children with gHAT, no differentiation is made between congenital gHAT and gHAT acquired later. There is a lack of knowledge regarding the signs and symptoms attributable to congenital gHAT and its long-term sequelae. METHODS Following an evaluation of the hospital register for gHAT, the authors observed that six children born to mothers with gHAT during their pregnancies still had sequelae of the infection. The six mothers were interviewed about their respective pregnancies and the developmental history of the children borne to the infected mothers. Furthermore, the children then underwent a complete physical examination with a focus on neuropsychiatric signs and symptoms. RESULTS Five of the six patients are still seriously disabled. Behavioral changes are present in four patients, tremor, speech impairment, involuntary movements and pathologic the Barrés test and Mingazzini test in three patients and convulsions, pyramidal signs and decreased muscle tonus in two patients. Two patients cannot work and one has a sphincter disorder. CONCLUSIONS Our study suggests that congenital gHAT may lead to long-lasting sequelae in babies born to mothers treated after delivery. The risk of embryo toxicity of treatment of mothers with gHAT must be balanced against the risk of congenital gHAT with long-term sequelae.
Collapse
Affiliation(s)
- Junior Mudji
- Hôpital Evangélique de Vanga, Vanga Mission, B.P. 4728 Kinshasa 2, Democratic Republic of the Congo.,Protestant University of Congo, Department of Family Medicine and Primary Care, B.P. 4745, Kinshasa 2, Democratic Republic of the Congo
| | - Esther Künzli
- Swiss Tropical and Public Health Institute, Medical Department, 4002 Basel Switzerland.,University of Basel, 4001 Basel, Switzerland
| | - David Molyneux
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Pembroke Place, L3 5QA, UK
| | - Johannes Blum
- Hôpital Evangélique de Vanga, Vanga Mission, B.P. 4728 Kinshasa 2, Democratic Republic of the Congo.,Swiss Tropical and Public Health Institute, Medical Department, 4002 Basel Switzerland.,University of Basel, 4001 Basel, Switzerland
| |
Collapse
|
6
|
Grob D, Conejeros I, Velásquez ZD, Preußer C, Gärtner U, Alarcón P, Burgos RA, Hermosilla C, Taubert A. Trypanosoma brucei brucei Induces Polymorphonuclear Neutrophil Activation and Neutrophil Extracellular Traps Release. Front Immunol 2020; 11:559561. [PMID: 33193328 PMCID: PMC7649812 DOI: 10.3389/fimmu.2020.559561] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Accepted: 08/18/2020] [Indexed: 12/12/2022] Open
Abstract
Trypanosoma brucei brucei trypomastigotes are classical blood parasites of cattle, these stages might become potential targets for circulating polymorphonuclear neutrophils (PMN). We here investigated NETs extrusion and related oxygen consumption in bovine PMN exposed to motile T. b. brucei trypomastigotes in vitro. Parasite exposure induced PMN activation as detected by enhanced oxygen consumption rates (OCR), extracellular acidification rates (ECAR), and production of total and extracellular reactive oxygen species (ROS). Scanning electron microscopy (SEM) showed that co-cultivation of bovine PMN with motile trypomastigotes resulted in NETs formation within 120 min of exposure. T. b. brucei-induced NETs were confirmed by confocal microscopy demonstrating co-localization of extruded DNA with neutrophil elastase (NE) and nuclear histones. Immunofluorescence analyses demonstrated that trypomastigotes induced different phenotypes of NETs in bovine PMN, such as aggregated NETs (aggNETs), spread NETs (sprNETs), and diffuse NETs (diffNETs) with aggNETs being the most abundant ones. Furthermore, live cell 3D-holotomographic microscopy unveiled detailed morphological changes during the NETotic process. Quantification of T. b. brucei-induced NETs formation was estimated by DNA and nuclear area analysis (DANA) and confirmed enhanced NETs formation in response to trypomastigote stages. Formation of NETs does not result in a decrease of T. b. brucei viability, but a decrease of 26% in the number of motile parasites. Referring the involved signaling pathways, trypomastigote-induced NETs formation seems to be purinergic-dependent, since inhibition via NF449 treatment resulted in a significant reduction of T. b. brucei-triggered DNA extrusion. Overall, future studies will have to analyze whether the formation of aggNETs indeed plays a role in the outcome of clinical disease and bovine African trypanosomiasis-related immunopathological disorders, such as increased intravascular coagulopathy and vascular permeability, often reported to occur in this disease.
Collapse
Affiliation(s)
- Daniela Grob
- Institute of Parasitology, Biomedical Research Center Seltersberg (BFS), Justus Liebig University Giessen, Giessen, Germany
| | - Iván Conejeros
- Institute of Parasitology, Biomedical Research Center Seltersberg (BFS), Justus Liebig University Giessen, Giessen, Germany
| | - Zahady D Velásquez
- Institute of Parasitology, Biomedical Research Center Seltersberg (BFS), Justus Liebig University Giessen, Giessen, Germany
| | - Christian Preußer
- Institute of Biochemistry, Department of Biology and Chemistry, Justus Liebig University Giessen, Giessen, Germany
| | - Ulrich Gärtner
- Institute of Anatomy and Cell Biology, Justus Liebig University Giessen, Giessen, Germany
| | - Pablo Alarcón
- Laboratory of Inflammation Pharmacology, Institute of Pharmacology and Morphophysiology, Universidad Austral de Chile, Valdivia, Chile
| | - Rafael A Burgos
- Laboratory of Inflammation Pharmacology, Institute of Pharmacology and Morphophysiology, Universidad Austral de Chile, Valdivia, Chile
| | - Carlos Hermosilla
- Institute of Parasitology, Biomedical Research Center Seltersberg (BFS), Justus Liebig University Giessen, Giessen, Germany
| | - Anja Taubert
- Institute of Parasitology, Biomedical Research Center Seltersberg (BFS), Justus Liebig University Giessen, Giessen, Germany
| |
Collapse
|
7
|
Mulenga P, Lutumba P, Coppieters Y, Mpanya A, Mwamba-Miaka E, Luboya O, Chenge F. Passive Screening and Diagnosis of Sleeping Sickness with New Tools in Primary Health Services: An Operational Research. Infect Dis Ther 2019; 8:353-367. [PMID: 31309434 PMCID: PMC6702524 DOI: 10.1007/s40121-019-0253-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Indexed: 11/25/2022] Open
Abstract
INTRODUCTION The integration of human African trypanosomiasis (HAT) activities into primary health services is gaining importance as a result of the decreasing incidence of HAT and the ongoing developments of new screening and diagnostic tools. In the Democratic Republic of Congo, this integration process faces multiple challenges. We initiated an operational research project to document drivers and bottlenecks of the process. METHODS Three health districts piloted the integration of HAT screening and diagnosis into primary health services. We analysed the outcome indicators of this intervention and conducted in-depth interviews with health care providers, seropositives, community health workers and HD management team members. Our thematic interview guide focused on factors facilitating and impeding the integration of HAT screening. RESULTS The study showed a HAT-RDT-positive rate of 2.2% in Yasa Bonga, 2.9% in Kongolo and 3% in Bibanga, while the proportion of reported seropositives that received confirmatory examinations was 76%, 45.6% and 68%, respectively. Qualitative analyses indicated that some seropositives were unable to access the confirmation facility. The main reasons that were given included distance, RDT rupture, lack of basic screening equipment and financial barriers (additional hospital fees not included in free treatment course), fear of lumbar puncture and the perception of HAT as a disease of supernatural origin. CONCLUSION Passive screening using HAT RDTs in primary health services inevitably has some limitations. However, regarding the epidemiological context and some obstacles to integrated implementation, this cannot on its own be a relevant alternative to the elimination of HAT by 2020. FUNDING We acknowledge the agency that provided financial support for this study, the Belgian Development Cooperation. The funder had no role in the study design, data collection and analysis, decision to publish or preparation of the manuscript. Philippe Mulenga received financial support thanks to a doctoral grant from the Belgian Development Cooperation under the FA4 agreement. Funding for the study and Rapid Service Fees was provided by the Epidemiology and Tropical Diseases Unit of the Institute of Tropical Medicine, Antwerp.
Collapse
Affiliation(s)
- Philippe Mulenga
- Faculty of Medicine & School of Public Health, University of Lubumbashi, Lubumbashi, Democratic Republic of the Congo.
- Department of Public Health, Institute of Tropical Medicine, Antwerp, Belgium.
- School of Public Health, Université Libre de Bruxelles, Brussels, Belgium.
| | - Pascal Lutumba
- Department of Tropical Medicine, University of Kinshasa, Faculty of Medicine, Kinshasa, Democratic Republic of the Congo
| | - Yves Coppieters
- School of Public Health, Université Libre de Bruxelles, Brussels, Belgium
| | - Alain Mpanya
- Programme National de Lutte contre la Trypanosomiase Humaine Africaine, Kinshasa, Democratic Republic of the Congo
| | - Eric Mwamba-Miaka
- Programme National de Lutte contre la Trypanosomiase Humaine Africaine, Kinshasa, Democratic Republic of the Congo
| | - Oscar Luboya
- Faculty of Medicine & School of Public Health, University of Lubumbashi, Lubumbashi, Democratic Republic of the Congo
| | - Faustin Chenge
- Faculty of Medicine & School of Public Health, University of Lubumbashi, Lubumbashi, Democratic Republic of the Congo
- Centre de Connaissances en Santé en République Démocratique du Congo, Kinshasa, Democratic Republic of the Congo
| |
Collapse
|
8
|
Mulenga P, Boelaert M, Lutumba P, Vander Kelen C, Coppieters Y, Chenge F, Lumbala C, Luboya O, Mpanya A. Integration of Human African Trypanosomiasis Control Activities into Primary Health Services in the Democratic Republic of the Congo: A Qualitative Study of Stakeholder Perceptions. Am J Trop Med Hyg 2019; 100:899-906. [PMID: 30719963 PMCID: PMC6447127 DOI: 10.4269/ajtmh.18-0382] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Human African trypanosomiasis is close to elimination in several countries in sub-Saharan Africa. The diagnosis and treatment is currently rapidly being integrated into first-line health services. We aimed to document the perspective of stakeholders on this integration process. We conducted 12 focus groups with communities in three health zones of the Democratic Republic of the Congo and held 32 interviews with health-care providers, managers, policy makers, and public health experts. The topic guide focused on enabling and blocking factors related to the integrated diagnosis and treatment approach. The data were analyzed with NVivo (QSR International, Melbourne, Australia) using a thematic analysis process. The results showed that the community mostly welcomed integrated care for diagnosis and treatment of sleeping sickness, as they value the proximity of first-line health services, but feared possible financial barriers. Health-care professionals thought integration contributed to the elimination goal but identified several implementation challenges, such as the lack of skills, equipment, motivation and financial resources in these basic health services. Patients often use multiple therapeutic itineraries that do not necessarily lead them to health centers where screening is available. Financial barriers are important, as health care is not free in first-line health centers, in contrast to the population screening campaigns. Communities and providers signal several challenges regarding the integration process. To succeed, the required training of health professionals, as well as staff deployment and remuneration policy and the financial barriers in the primary care system need to be addressed, to ensure coverage for those most in need.
Collapse
Affiliation(s)
- Philippe Mulenga
- Faculty of Medicine and School of Public Health, University of Lubumbashi, Lubumbashi, DRC.,Department of Public Health, Institute of Tropical Medicine, Antwerp, Belgium.,School of Public Health, Université Libre de Bruxelles, Brussels, Belgium
| | - Marleen Boelaert
- Department of Public Health, Institute of Tropical Medicine, Antwerp, Belgium
| | - Pascal Lutumba
- Department of Tropical Medicine, Faculty of Medicine, University of Kinshasa, Kinshasa, DRC
| | | | - Yves Coppieters
- School of Public Health, Université Libre de Bruxelles, Brussels, Belgium
| | - Faustin Chenge
- Faculty of Medicine and School of Public Health, University of Lubumbashi, Lubumbashi, DRC
| | - Crispin Lumbala
- National Program for the Control of Human African Trypanosomiasis, Kinshasa, DRC
| | - Oscar Luboya
- Faculty of Medicine and School of Public Health, University of Lubumbashi, Lubumbashi, DRC
| | - Alain Mpanya
- National Program for the Control of Human African Trypanosomiasis, Kinshasa, DRC
| |
Collapse
|
9
|
Masocha W, Kristensson K. Human African trypanosomiasis: How do the parasites enter and cause dysfunctions of the nervous system in murine models? Brain Res Bull 2018; 145:18-29. [PMID: 29870779 DOI: 10.1016/j.brainresbull.2018.05.022] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 05/24/2018] [Accepted: 05/30/2018] [Indexed: 12/27/2022]
Abstract
In this review we describe how Trypanosoma brucei brucei, a rodent pathogenic strain of African trypanosomes, can invade the nervous system, first by localization to the choroid plexus, the circumventricular organs (CVOs) and peripheral ganglia, which have fenestrated vessels, followed by crossing of the blood-brain barrier (BBB) into the white matter, hypothalamus, thalamus and basal ganglia. White blood cells (WBCs) pave the way for the trypanosome neuroinvasion. Experiments with immune deficient mice show that the invasion of WBCs is initiated by the toll-like receptor 9, followed by an augmentation phase that depends on the cytokine IFN-γ and the chemokine CXCL10. Nitric oxide (NO) derived from iNOS then prevents a break-down of the BBB and non-regulated passage of cells. This chain of events is relevant for design of better diagnostic tools to distinguish the different stages of the disease as well as for better understanding of the pathogenesis of the nervous system dysfunctions, which include circadian rhythm changes with sleep pattern disruption, pain syndromes, movement disorders and mental disturbances including dementia.
Collapse
Affiliation(s)
- Willias Masocha
- Department of Pharmacology and Therapeutics, Faculty of Pharmacy, Kuwait University, Kuwait.
| | | |
Collapse
|
10
|
Abstract
Sleeping sickness is a neglected tropical disease caused by Trypanosoma brucei parasites, affecting the poorest communities in sub-Saharan Africa. The great efforts done by the scientific community, local governments, and non-governmental organizations (NGOs) via active patients' screening, vector control, and introduction of improved treatment regimens have significantly contributed to the reduction of human African trypanosomiasis (HAT) incidence during the last 15 years. Consequently, the WHO has announced the objective of HAT elimination as a public health problem by 2020. Studies at both parasite and host levels have improved our understanding of the parasite biology and the mechanisms of parasite interaction with its mammalian host. In this review, the impact that 'omics studies have had on sleeping sickness by revealing novel properties of parasite's subcellular organelles are summarized, by highlighting changes induced in the host during the infection and by proposing potential disease markers and therapeutic targets.
Collapse
Affiliation(s)
- Natalia Tiberti
- Translational Biomarker Group, University of Geneva, Geneva, Switzerland
| | | |
Collapse
|
11
|
Stijlemans B, De Baetselier P, Caljon G, Van Den Abbeele J, Van Ginderachter JA, Magez S. Nanobodies As Tools to Understand, Diagnose, and Treat African Trypanosomiasis. Front Immunol 2017; 8:724. [PMID: 28713367 PMCID: PMC5492476 DOI: 10.3389/fimmu.2017.00724] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2017] [Accepted: 06/08/2017] [Indexed: 02/04/2023] Open
Abstract
African trypanosomes are strictly extracellular protozoan parasites that cause diseases in humans and livestock and significantly affect the economic development of sub-Saharan Africa. Due to an elaborate and efficient (vector)–parasite–host interplay, required to complete their life cycle/transmission, trypanosomes have evolved efficient immune escape mechanisms that manipulate the entire host immune response. So far, not a single field applicable vaccine exists, and chemotherapy is the only strategy available to treat the disease. Current therapies, however, exhibit high drug toxicity and an increased drug resistance is being reported. In addition, diagnosis is often hampered due to the inadequacy of current diagnostic procedures. In the context of tackling the shortcomings of current treatment and diagnostic approaches, nanobodies (Nbs, derived from the heavy chain-only antibodies of camels and llamas) might represent unmet advantages compared to conventional tools. Indeed, the combination of their small size, high stability, high affinity, and specificity for their target and tailorability represents a unique advantage, which is reflected by their broad use in basic and clinical research to date. In this article, we will review and discuss (i) diagnostic and therapeutic applications of Nbs that are being evaluated in the context of African trypanosomiasis, (ii) summarize new strategies that are being developed to optimize their potency for advancing their use, and (iii) document on unexpected properties of Nbs, such as inherent trypanolytic activities, that besides opening new therapeutic avenues, might offer new insight in hidden biological activities of conventional antibodies.
Collapse
Affiliation(s)
- Benoit Stijlemans
- Laboratory of Cellular and Molecular Immunology, Vrije Universiteit Brussel (VUB), Brussels, Belgium.,Myeloid Cell Immunology Lab, VIB-UGent Center for Inflammation Research, Ghent, Belgium
| | - Patrick De Baetselier
- Laboratory of Cellular and Molecular Immunology, Vrije Universiteit Brussel (VUB), Brussels, Belgium.,Myeloid Cell Immunology Lab, VIB-UGent Center for Inflammation Research, Ghent, Belgium
| | - Guy Caljon
- Laboratory of Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp (UA), Antwerp, Belgium
| | - Jan Van Den Abbeele
- Unit of Veterinary Protozoology, Department of Biomedical Sciences, Institute of Tropical Medicine Antwerp (ITM), Antwerp, Belgium
| | - Jo A Van Ginderachter
- Laboratory of Cellular and Molecular Immunology, Vrije Universiteit Brussel (VUB), Brussels, Belgium.,Myeloid Cell Immunology Lab, VIB-UGent Center for Inflammation Research, Ghent, Belgium
| | - Stefan Magez
- Laboratory of Cellular and Molecular Immunology, Vrije Universiteit Brussel (VUB), Brussels, Belgium.,Laboratory for Biomedical Research, Ghent University Global Campus, Incheon, South Korea
| |
Collapse
|
12
|
Stijlemans B, Radwanska M, De Trez C, Magez S. African Trypanosomes Undermine Humoral Responses and Vaccine Development: Link with Inflammatory Responses? Front Immunol 2017; 8:582. [PMID: 28596768 PMCID: PMC5442186 DOI: 10.3389/fimmu.2017.00582] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 05/01/2017] [Indexed: 01/15/2023] Open
Abstract
African trypanosomosis is a debilitating disease of great medical and socioeconomical importance. It is caused by strictly extracellular protozoan parasites capable of infecting all vertebrate classes including human, livestock, and game animals. To survive within their mammalian host, trypanosomes have evolved efficient immune escape mechanisms and manipulate the entire host immune response, including the humoral response. This report provides an overview of how trypanosomes initially trigger and subsequently undermine the development of an effective host antibody response. Indeed, results available to date obtained in both natural and experimental infection models show that trypanosomes impair homeostatic B-cell lymphopoiesis, B-cell maturation and survival and B-cell memory development. Data on B-cell dysfunctioning in correlation with parasite virulence and trypanosome-mediated inflammation will be discussed, as well as the impact of trypanosomosis on heterologous vaccine efficacy and diagnosis. Therefore, new strategies aiming at enhancing vaccination efficacy could benefit from a combination of (i) early parasite diagnosis, (ii) anti-trypanosome (drugs) treatment, and (iii) anti-inflammatory treatment that collectively might allow B-cell recovery and improve vaccination.
Collapse
Affiliation(s)
- Benoit Stijlemans
- Laboratory of Cellular and Molecular Immunology, Vrije Universiteit Brussel (VUB), Brussels, Belgium.,Myeloid Cell Immunology Lab, VIB-UGent Center for Inflammation Research, Ghent, Belgium
| | - Magdalena Radwanska
- Laboratory for Biomedical Research, Ghent University Global Campus, Yeonsu-Gu, Incheon, South Korea
| | - Carl De Trez
- Laboratory of Cellular and Molecular Immunology, Vrije Universiteit Brussel (VUB), Brussels, Belgium.,Structural Biology Research Centre (SBRC), VIB, Brussels, Belgium
| | - Stefan Magez
- Laboratory of Cellular and Molecular Immunology, Vrije Universiteit Brussel (VUB), Brussels, Belgium.,Laboratory for Biomedical Research, Ghent University Global Campus, Yeonsu-Gu, Incheon, South Korea
| |
Collapse
|
13
|
Affiliation(s)
- Lucy Hedley
- Senior Clinical Pharmacist in HIV and Infectious Diseases in the Department of Pharmacy, University College London Hospitals NHS Foundation Trust, London NW1 2BU
| | - Douglas Fink
- Registrar in Infectious Diseases and General Internal Medicine in the Department of Infectious Diseases, University College London Hospitals NHS Foundation Trust, London
| | - Dominic Sparkes
- Foundation Doctor in Infectious Diseases in the Department of Infectious Diseases, University College London Hospitals NHS Foundation Trust, London
| | - Peter L Chiodini
- Consultant Parasitologist in the Department of Infectious Diseases and Parasitology, Hospital for Tropical Diseases, London
| |
Collapse
|
14
|
Burri C, Blum J. Human African Trypanosomiasis. Infect Dis (Lond) 2017. [DOI: 10.1016/b978-0-7020-6285-8.00110-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
|
15
|
Tanowitz HB, Scherer PE, Mota MM, Figueiredo LM. Adipose Tissue: A Safe Haven for Parasites? Trends Parasitol 2016; 33:276-284. [PMID: 28007406 DOI: 10.1016/j.pt.2016.11.008] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Revised: 11/17/2016] [Accepted: 11/28/2016] [Indexed: 12/13/2022]
Abstract
Adipose tissue (AT) is no longer regarded as an inert lipid storage, but as an important central regulator in energy homeostasis and immunity. Three parasite species are uniquely associated with AT during part of their life cycle: Trypanosoma cruzi, the causative agent of Chagas disease; Trypanosoma brucei, the causative agent of African sleeping sickness; and Plasmodium spp., the causative agents of malaria. In AT, T. cruzi resides inside adipocytes, T. brucei is found in the interstitial spaces between adipocytes, while Plasmodium spp. infect red blood cells, which may adhere to the blood vessels supplying AT. Here, we discuss how each parasite species adapts to this tissue environment and what the implications are for pathogenesis, clinical manifestations, and therapy.
Collapse
Affiliation(s)
- Herbert B Tanowitz
- Department of Pathology, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Philipp E Scherer
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390-8549, USA; Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Maria M Mota
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal
| | - Luisa M Figueiredo
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal.
| |
Collapse
|
16
|
McCarroll CS, Rossor CL, Morrison LR, Morrison LJ, Loughrey CM. A Pre-clinical Animal Model of Trypanosoma brucei Infection Demonstrating Cardiac Dysfunction. PLoS Negl Trop Dis 2015; 9:e0003811. [PMID: 26023927 PMCID: PMC4449042 DOI: 10.1371/journal.pntd.0003811] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Accepted: 05/04/2015] [Indexed: 11/19/2022] Open
Abstract
African trypanosomiasis (AT), caused by Trypanosoma brucei species, results in both neurological and cardiac dysfunction and can be fatal if untreated. Research on the pathogenesis and treatment of the disease has centred to date on the characteristic neurological symptoms, whereas cardiac dysfunction (e.g. ventricular arrhythmias) in AT remains largely unstudied. Animal models of AT demonstrating cardiac dysfunction similar to that described in field cases of AT are critically required to transform our understanding of AT-induced cardiac pathophysiology and identify future treatment strategies. We have previously shown that T. brucei can interact with heart muscle cells (cardiomyocytes) to induce ventricular arrhythmias in ex vivo adult rat hearts. However, it is unknown whether the arrhythmias observed ex vivo are also present during in vivo infection in experimental animal models. Here we show for the first time the characterisation of ventricular arrhythmias in vivo in two animal models of AT infection using electrocardiographic (ECG) monitoring. The first model utilised a commonly used monomorphic laboratory strain, Trypanosoma brucei brucei Lister 427, whilst the second model used a pleomorphic laboratory strain, T. b. brucei TREU 927, which demonstrates a similar chronic infection profile to clinical cases. The frequency of ventricular arrhythmias and heart rate (HR) was significantly increased at the endpoint of infection in the TREU 927 infection model, but not in the Lister 427 infection model. At the end of infection, hearts from both models were isolated and Langendorff perfused ex vivo with increasing concentrations of the β-adrenergic agonist isoproterenol (ISO). Interestingly, the increased frequency of arrhythmias observed in vivo in the TREU 927 infection model was lost upon isolation of the heart ex vivo, but re-emerged with the addition of ISO. Our results demonstrate that TREU 927 infection modifies the substrate of the myocardium in such a way as to increase the propensity for ventricular arrhythmias in response to a circulating factor in vivo or β-adrenergic stimulation ex vivo. The TREU 927 infection model provides a new opportunity to accelerate our understanding of AT-related cardiac pathophysiology and importantly has the required sensitivity to monitor adverse cardiac-related electrical dysfunction when testing new therapeutic treatments for AT.
Collapse
Affiliation(s)
- Charlotte S. McCarroll
- Institute of Cardiovascular and Medical Sciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Charlotte L. Rossor
- Institute of Cardiovascular and Medical Sciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Linda R. Morrison
- Easter Bush Pathology, Royal (Dick) School of Veterinary Studies and The Roslin Institute, Easter Bush Campus, University of Edinburgh, Midlothian, United Kingdom
| | - Liam J. Morrison
- Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
- Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian, United Kingdom
| | - Christopher M. Loughrey
- Institute of Cardiovascular and Medical Sciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
- * E-mail:
| |
Collapse
|
17
|
Increased acute immune response during the meningo-encephalitic stage of Trypanosoma brucei rhodesiense sleeping sickness compared to Trypanosoma brucei gambiense. TRANSLATIONAL PROTEOMICS 2015. [DOI: 10.1016/j.trprot.2014.11.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
|
18
|
Enantiospecific reassessment of the pharmacokinetics and pharmacodynamics of oral eflornithine against late-stage Trypanosoma brucei gambiense sleeping sickness. Antimicrob Agents Chemother 2014; 59:1299-307. [PMID: 25512417 DOI: 10.1128/aac.04101-14] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
This study aimed to characterize the stereoselective pharmacokinetics of oral eflornithine in 25 patients with late-stage Trypanosoma brucei gambiense sleeping sickness. A secondary aim was to determine the concentrations of L- and D-eflornithine required in plasma or cerebrospinal fluid (CSF) for an efficient eradication of the T. brucei gambiense parasites. Patients were randomly allocated to receive either 100 (group I, n=12) or 125 (group II, n=13) mg/kg of body weight of drug every 6 h for 14 days. The concentrations of L- and D-eflornithine in the plasma and CSF samples were measured using a stereospecific liquid chromatographic method. Nonlinear mixed-effects modeling was used to characterize the plasma pharmacokinetics. The plasma concentrations of L-eflornithine were on average 52% (95% confidence interval [CI], 51, 54%; n=321) of the D-enantiomer concentrations. The typical oral clearances of L- and D-eflornithine were 17.4 (95% CI, 15.5, 19.3) and 8.23 (95% CI, 7.36, 9.10) liters/h, respectively. These differences were likely due to stereoselective intestinal absorption. The distributions of eflornithine enantiomers to the CSF were not stereoselective. A correlation was found between the probability of cure and plasma drug exposure, although it was not more pronounced for the L-enantiomer than for that of total eflornithine. This study may explain why oral treatment for late-stage human African trypanosomiasis (HAT) patients with racemic eflornithine has previously failed; the more potent L-enantiomer is present at much lower concentrations in both plasma and CSF than those of the D-enantiomer. Eflornithine stereoselective pharmacokinetics needs to be considered if an oral dosage regimen is to be explored further.
Collapse
|
19
|
Elliott I, Patel T, Shah J, Venkatesan P. West-African trypanosomiasis in a returned traveller from Ghana: an unusual cause of progressive neurological decline. BMJ Case Rep 2014; 2014:bcr2014204451. [PMID: 25123570 PMCID: PMC4139564 DOI: 10.1136/bcr-2014-204451] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/25/2014] [Indexed: 11/04/2022] Open
Abstract
West-African trypanosomiasis caused by Trypanosoma brucei gambiense is a rare imported infection presenting with somnolence, lymphadenopathy and wide-ranging neurological symptoms. A 67-year-old Caucasian man presented with a 10-month history of cognitive deterioration, ataxic gait, somnolence and urinary incontinence. His symptoms had progressed more rapidly over the course of a month prior to admission. Serological testing confirmed a diagnosis of West-African trypanosomiasis. The patient was successfully treated with eflornithine and made a good recovery. West-African trypanosomiasis should be considered in the differential diagnosis of unexplained cognitive decline in those with a relevant travel history. If left untreated, the condition is universally fatal.
Collapse
Affiliation(s)
- Ivo Elliott
- Department of Infectious Diseases, Nottingham University Hospitals City Campus, Nottingham, UK
| | | | - Jagrit Shah
- Department of Radiology, Nottingham University Hospitals, Nottingham, USA
| | - Pradhib Venkatesan
- Department of Infectious Diseases, Nottingham University Hospitals City Campus, Nottingham, UK
| |
Collapse
|
20
|
Neurological trypanosomiasis in quinapyramine sulfate-treated horses--a breach of the blood-brain barrier? Trop Anim Health Prod 2013; 46:371-7. [PMID: 24197687 DOI: 10.1007/s11250-013-0498-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/24/2013] [Indexed: 10/26/2022]
Abstract
Trypanosoma evansi infection typically produces wasting disease, but it can also develop into a neurological or meningoencephalitis form in equids. Trypanosomiasis in horses was treated with quinapyramine sulfate, and all the 14 infected animals were recovered clinically. After clinical recovery, four animals developed a neurological form of the disease at various intervals. Two of these animals treated with diminazene aceturate recovered temporarily. Repeated attempts failed to find the parasite in the blood or the cerebrospinal fluid (CSF), but all of the animals were positive in enzyme-linked immunosorbent assay. The calculation of the antibody index (AI) in the serum and the CSF and polymerase chain reaction (PCR) analysis of the CSF and brain tissue were carried out to confirm the neuro-infection. We found PCR and AI analyses of the CSF to be useful tools in the diagnosis of the neurological form of trypanosomiasis when the organism cannot be found in the blood or CSF. The increased albumin quotient is indicative of barrier leakage due to neuroinflammation. The biochemical changes in the CSF due to nervous system trypanosomiasis include increases in the albumin quotient, total protein, and urea nitrogen. It seems to be the first report on relapse of the nervous form of trypanosomiasis in equids even after quinapyramine treatment in endemic areas.
Collapse
|
21
|
Roussaki M, Hall B, Lima SC, da Silva AC, Wilkinson S, Detsi A. Synthesis and anti-parasitic activity of a novel quinolinone-chalcone series. Bioorg Med Chem Lett 2013; 23:6436-41. [PMID: 24119553 DOI: 10.1016/j.bmcl.2013.09.047] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2013] [Revised: 09/13/2013] [Accepted: 09/16/2013] [Indexed: 01/03/2023]
Abstract
A series of novel quinolinone-chalcone hybrids and analogues were designed, synthesized and their biological activity against the mammalian stages of Trypanosoma brucei and Leishmania infantum evaluated. Promising molecular scaffolds with significant microbicidal activity and low cytotoxicity were identified. Quinolinone-chalcone 10 exhibited anti-parasitic properties against both organisms, being the most potent anti-L. infantum agent of the entire series (IC50 value of 1.3±0.1 μM). Compounds 4 and 11 showed potency toward the intracellular, amastigote stage of L. infantum (IC50 values of 2.1±0.6 and 3.1±1.05 μM, respectively). Promising trypanocidal compounds include 5 and 10 (IC50 values of 2.6±0.1 and 3.3±0.1 μM, respectively) as well as 6 and 9 (both having IC50 values of <5 μM). Chemical modifications on the quinolinone-chalcone scaffold were performed on selected compounds in order to investigate the influence of these structural features on antiparasitic activity.
Collapse
Affiliation(s)
- Marina Roussaki
- Laboratory of Organic Chemistry, School of Chemical Engineering, National Technical University of Athens, Zografou Campus, 15780 Athens, Greece
| | | | | | | | | | | |
Collapse
|
22
|
|
23
|
Translation of human African trypanosomiasis biomarkers towards field application. TRANSLATIONAL PROTEOMICS 2013. [DOI: 10.1016/j.trprot.2013.04.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
|
24
|
Abstract
Human African trypanosomiasis or sleeping sickness is a neglected tropical disease that affects populations in sub-Saharan Africa. The disease is caused by infection with the gambiense and rhodesiense subspecies of the extracellular parasite Trypanosoma brucei, and is transmitted to humans by bites of infected tsetse flies. The disease evolves in two stages, the hemolymphatic and meningoencephalitic stages, the latter being defined by central nervous system infection after trypanosomal traversal of the blood-brain barrier. African trypanosomiasis, which leads to severe neuroinflammation, is fatal without treatment, but the available drugs are toxic and complicated to administer. The choice of medication is determined by the infecting parasite subspecies and disease stage. Clinical features include a constellation of nonspecific symptoms and signs with evolving neurological and psychiatric alterations and characteristic sleep-wake disturbances. Because of the clinical profile variability and insidiously progressive central nervous system involvement, disease staging is currently based on cerebrospinal fluid examination, which is usually performed after the finding of trypanosomes in blood or other body fluids. No vaccine being available, control of human African trypanosomiasis relies on diagnosis and treatment of infected patients, assisted by vector control. Better diagnostic tools and safer, easy to use drugs are needed to facilitate elimination of the disease.
Collapse
Affiliation(s)
- Veerle Lejon
- Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium and Institut de Recherche pour le Développement, UMR 177 IRD-CIRAD INTERTRYP, Campus International de Baillarguet, Montpellier, France.
| | | | | |
Collapse
|
25
|
Bouteille B, Buguet A. The detection and treatment of human African trypanosomiasis. Res Rep Trop Med 2012; 3:35-45. [PMID: 30890865 DOI: 10.2147/rrtm.s24751] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Human African trypanosomiasis (HAT) is caused by the injection of Trypanosoma brucei (T. b.) gambiense or T. b. rhodesiense by Glossina, the tsetse fly. Three historical eras followed the exclusive clinical approach of the 19th century. At the turn of the century, the "initial research" era was initiated because of the dramatic spread of HAT throughout intertropical Africa, and scientists discovered the agent and its vector. Two entities, recurrent fever and sleeping sickness, were then considered a continuum between hemolymphatic stage 1 and meningoencephalitic stage 2. Treatments were developed. Soon after World War I, specific services and mobile teams were created, initiating the "epidemiological" era, during which populations were visited, screened, and treated. As a result, by 1960, annual new cases were rare. New mass screening and staging tools were then developed in a third, "modern" era, especially to counter a new epidemic wave. Currently, diagnosis still relies on microscopic detection of trypanosomes without (wet and thick blood films) or with concentration techniques (capillary tube centrifugation, miniature anion-exchange centrifugation technique). Staging is a vital step. Stage 1 patients are treated on site with pentamidine or suramin. However, stage 2 patients are treated in specialized facilities, using drugs that are highly toxic and/or that require complex administration procedures (melarsoprol, eflornithine, or nifurtimox-eflornithine combination therapy). Suramin and melarsoprol are the only medications active against Rhodesian HAT. Staging still relies on cerebrospinal fluid examination for trypanosome detection and white blood cell counts: stage 1, absence of trypanosomes, white blood cell counts ≤ 5/µL; stage 2, presence of trypanosomes, white blood cell counts ≥ 20/µL; T. b. gambiense HAT intermediate stage, between these still controversial thresholds. Our group has proposed the use of noninvasive ambulatory polysomnography to identify sleep-wake abnormalities characteristic of stage 2 of the disease. Only patients with abnormal sleep-wake patterns would then undergo confirmative lumbar puncture.
Collapse
Affiliation(s)
- Bernard Bouteille
- Laboratory of Parasitology, Dupuytren University Hospital of Limoges, France,
| | - Alain Buguet
- Polyclinic Marie-Louise Poto-Djembo, Pointe-Noire, Congo
| |
Collapse
|
26
|
Wise E, Easom N, Watson J, Bailey R, Brown M. Lesson of the month: a psychiatric diagnosis overturned by a blood film. Clin Med (Lond) 2012; 12:295-6. [PMID: 22783788 PMCID: PMC4953499 DOI: 10.7861/clinmedicine.12-3-295] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Emily Wise
- Hospital for Tropical Diseases, University College London Hospitals NHS Trust, London.
| | | | | | | | | |
Collapse
|
27
|
Seke Etet PF, Mahomoodally MF. New insights in staging and chemotherapy of African trypanosomiasis and possible contribution of medicinal plants. ScientificWorldJournal 2012; 2012:343652. [PMID: 22593674 PMCID: PMC3349134 DOI: 10.1100/2012/343652] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2011] [Accepted: 11/16/2011] [Indexed: 11/17/2022] Open
Abstract
Human African trypanosomiasis (HAT) is a fatal if untreated fly-borne neuroinflammatory disease caused by protozoa of the species Trypanosoma brucei (T.b.). The increasing trend of HAT cases has been reversed, but according to WHO experts, new epidemics of this disease could appear. In addition, HAT is still a considerable burden for life quality and economy in 36 sub-Saharan Africa countries with 15-20 million persons at risk. Following joined initiatives of WHO and private partners, the fight against HAT was re-engaged, resulting in considerable breakthrough. We present here what is known at this day about HAT etiology and pathogenesis and the new insights in the development of accurate tools and tests for disease staging and severity monitoring in the field. Also, we elaborate herein the promising progresses made in the development of less toxic and more efficient trypanocidal drugs including the potential of medicinal plants and related alternative drug therapies.
Collapse
Affiliation(s)
- Paul F Seke Etet
- Department of Neurological Sciences (DNNMMS), University of Verona, Via Delle Grazie 8, 37134 Verona, Italy
| | | |
Collapse
|
28
|
Etet PFS, Palomba M, Colavito V, Grassi-Zucconi G, Bentivoglio M, Bertini G. Sleep and Rhythm Changes at the Time ofTrypanosoma bruceiInvasion of the Brain Parenchyma in the Rat. Chronobiol Int 2012; 29:469-81. [DOI: 10.3109/07420528.2012.660713] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
|
29
|
Njamnshi AK, Seke Etet PF, Perrig S, Acho A, Funsah JY, Mumba D, Muyembe JJ, Kristensson K, Bentivoglio M. Actigraphy in human African trypanosomiasis as a tool for objective clinical evaluation and monitoring: a pilot study. PLoS Negl Trop Dis 2012; 6:e1525. [PMID: 22348168 PMCID: PMC3279345 DOI: 10.1371/journal.pntd.0001525] [Citation(s) in RCA: 24] [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: 08/01/2011] [Accepted: 12/29/2011] [Indexed: 02/05/2023] Open
Abstract
Background Human African trypanosomiasis (HAT) or sleeping sickness leads to a complex neuropsychiatric syndrome with characteristic sleep alterations. Current division into a first, hemolymphatic stage and second, meningoencephalitic stage is primarily based on the detection of white blood cells and/or trypanosomes in the cerebrospinal fluid. The validity of this criterion is, however, debated, and novel laboratory biomarkers are under study. Objective clinical HAT evaluation and monitoring is therefore needed. Polysomnography has effectively documented sleep-wake disturbances during HAT, but could be difficult to apply as routine technology in field work. The non-invasive, cost-effective technique of actigraphy has been widely validated as a tool for the ambulatory evaluation of sleep disturbances. In this pilot study, actigraphy was applied to the clinical assessment of HAT patients. Methods/Principal Findings Actigraphy was recorded in patients infected by Trypanosoma brucei gambiense, and age- and sex-matched control subjects. Simultaneous nocturnal polysomnography was also performed in the patients. Nine patients, including one child, were analyzed at admission and two of them also during specific treatment. Parameters, analyzed with user-friendly software, included sleep time evaluated from rest-activity signals, rest-activity rhythm waveform and characteristics. The findings showed sleep-wake alterations of various degrees of severity, which in some patients did not parallel white blood cell counts in the cerebrospinal fluid. Actigraphic recording also showed improvement of the analyzed parameters after treatment initiation. Nocturnal polysomnography showed alterations of sleep time closely corresponding to those derived from actigraphy. Conclusions/Significance The data indicate that actigraphy can be an interesting tool for HAT evaluation, providing valuable clinical information through simple technology, well suited also for long-term follow-up. Actigraphy could therefore objectively contribute to the clinical assessment of HAT patients. This method could be incorporated into a clinical scoring system adapted to HAT to be used in the evaluation of novel treatments and laboratory biomarkers. The clinical picture of the parasitic disease human African trypanosomiasis (HAT, also called sleeping sickness) is dominated by sleep alterations. We here used actigraphy to evaluate patients affected by the Gambiense form of HAT. Actigraphy is based on the use of battery-run, wrist-worn devices similar to watches, widely used in middle-high income countries for ambulatory monitoring of sleep disturbances. This pilot study was motivated by the fact that the use of polysomnography, which is the gold standard technology for the evaluation of sleep disorders and has greatly contributed to the objective identification of signs of disease in HAT, faces tangible challenges in resource-limited countries where the disease is endemic. We here show that actigraphy provides objective data on the severity of sleep-wake disturbances that characterize HAT. This technique, which does not disturb the patient's routine activities and can be applied at home, could therefore represent an interesting, non-invasive tool for objective HAT clinical assessment and long-term monitoring under field conditions. The use of this method could provide an adjunct marker of HAT severity and for treatment follow-up, or be evaluated in combination with other disease biomarkers in body fluids that are currently under investigation in many laboratories.
Collapse
Affiliation(s)
- Alfred K Njamnshi
- Neurology Department, Central Hospital Yaoundé/Faculty of Medicine, University of Yaoundé I, Yaoundé, Cameroon.
| | | | | | | | | | | | | | | | | |
Collapse
|
30
|
Abstract
Human African trypanosomiasis (HAT), or sleeping sickness, is a vector-borne disease that flourishes in impoverished, rural parts of sub-Saharan Africa. It is caused by infection with the protozoan parasite Trypanosoma brucei and is transmitted by tsetse flies of the genus Glossina. The majority of cases are caused by T. b. gambiense, which gives rise to the chronic, anthroponotic endemic disease in Western and Central Africa. Infection with T. b. rhodesiense leads to the acute, zoonotic form of Eastern and Southern Africa. The parasites live and multiply extracellularly in the blood and tissue fluids of their human host. They have elaborated a variety of strategies for invading hosts, to escape the immune system and to take advantage of host growth factors. HAT is a challenging and deadly disease owing to its complex epidemiology and clinical presentation and, if left untreated, can result in high death rates. As one of the most neglected tropical diseases, HAT is characterized by the limited availability of safe and cost-effective control tools. No vaccine against HAT is available, and the toxicity of existing old and cumbersome drugs precludes the adoption of control strategies based on preventive chemotherapy. As a result, the keystones of interventions against sleeping sickness are active and passive case-finding for early detection of cases followed by treatment, vector control and animal reservoir management. New methods to diagnose and treat patients and to control transmission by the tsetse fly are needed to achieve the goal of global elimination of the disease.
Collapse
Affiliation(s)
- D Malvy
- Travel Clinics and Division of Tropical Medicine and Imported Diseases, Department of Internal Medicine and Tropical Diseases, University Hospital Centre, Bordeaux, France.
| | | |
Collapse
|
31
|
Blum JA, Neumayr AL, Hatz CF. Human African trypanosomiasis in endemic populations and travellers. Eur J Clin Microbiol Infect Dis 2011; 31:905-13. [PMID: 21901632 DOI: 10.1007/s10096-011-1403-y] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2011] [Accepted: 08/22/2011] [Indexed: 11/25/2022]
Abstract
Human African trypanosomiasis (HAT) or sleeping sickness is caused by the protozoan parasites Trypanosoma brucei (T.b.) gambiense (West African form) and T.b. rhodesiense (East African form) that are transmitted by the bite of the tsetse fly, Glossina spp.. Whereas most patients in endemic populations are infected with T.b. gambiense, most tourists are infected with T.b. rhodesiense. In endemic populations, T.b. gambiense HAT is characterized by chronic and intermittent fever, headache, pruritus, and lymphadenopathy in the first stage and by sleep disturbances and neuro-psychiatric disorders in the second stage. Recent descriptions of the clinical presentation of T.b. rhodesiense in endemic populations show a high variability in different foci. The symptomatology of travellers is markedly different from the usual textbook descriptions of African HAT patients. The onset of both infections is almost invariably an acute and febrile disease. Diagnosis and treatment are difficult and rely mostly on old methods and drugs. However, new molecular diagnostic technologies are under development. A promising new drug combination is currently evaluated in a phase 3 b study and further new drugs are under evaluation.
Collapse
Affiliation(s)
- J A Blum
- Medical Department, Swiss Tropical and Public Health Institute, Socinstrasse 57, 4002, Basel, Switzerland.
| | | | | |
Collapse
|
32
|
Batista JS, Rodrigues CMF, García HA, Bezerra FSB, Olinda RG, Teixeira MMG, Soto-Blanco B. Association of Trypanosoma vivax in extracellular sites with central nervous system lesions and changes in cerebrospinal fluid in experimentally infected goats. Vet Res 2011; 42:63. [PMID: 21569364 PMCID: PMC3105954 DOI: 10.1186/1297-9716-42-63] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2010] [Accepted: 05/11/2011] [Indexed: 11/10/2022] Open
Abstract
Changes in cerebrospinal fluid (CSF) and anatomical and histopathological central nervous system (CNS) lesions were evaluated, and the presence of Trypanosoma vivax in CNS tissues was investigated through PCR. Twelve adult male goats were divided into three groups (G): G1, infected with T. vivax and evaluated during the acute phase; G2, infected goats evaluated during the chronic phase; and G3, consisting of non-infected goats. Each goat from G1 and G2 was infected with 1.25 × 105 trypomastigotes. Cerebrospinal fluid (CSF) analysis and investigation of T. vivax was performed at the 15th day post-infection (dpi) in G1 goats and on the fifth day after the manifestation of nervous system infection signs in G2 goats. All goats were necropsied, and CNS fragments from G1 and G2 goats were evaluated by PCR for the determination of T. vivax. Hyperthermia, anemia and parasitemia were observed from the fifth dpi for G1 and G2, with the highest parasitemia peak between the seventh and 21st dpi. Nervous system infection signs were observed in three G2 goats between the 30th and 35th dpi. CSF analysis revealed the presence of T. vivax for G2. Meningitis and meningoencephalitis were diagnosed in G2. PCR were positive for T. vivax in all the samples tested. In conclusion, T. vivax may reach the nervous tissue resulting in immune response from the host, which is the cause of progressive clinical and pathological manifestations of the CNS in experimentally infected goats.
Collapse
Affiliation(s)
- Jael S Batista
- Department of Animal Sciences, Universidade Federal Rural do Semi-árido (UFERSA), BR 110 - Km 47, CEP: 59625-900, Mossoró-RN, Brazil.
| | | | | | | | | | | | | |
Collapse
|
33
|
Spermine synthase activity affects the content of decarboxylated S-adenosylmethionine. Biochem J 2010; 433:139-44. [DOI: 10.1042/bj20101228] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
dcAdoMet (decarboxylated S-adenosylmethionine) is an essential intermediate in the synthesis of polyamines. Its content is normally very low, amounting to less than 5% of that of S-adenosylmethionine itself. It was found that in mice lacking spermine synthase there was a large increase in dcAdoMet and that overexpression of spermine synthase reduced the amount of this nucleoside. There was also an increase in dcAdoMet in cells derived from patients with Snyder–Robinson syndrome, a rare X-linked recessive human disease caused by SMS gene mutations that greatly reduce the content of spermine synthase. These results suggest that there is an inverse relationship between the amount of spermine synthase protein and the content of dcAdoMet and raise the possibility that some of the abnormalities seen in mammals deficient in spermine synthase might be due to changes in dcAdoMet pools.
Collapse
|
34
|
Abstract
American (Chagas disease) and African (sleeping sickness) trypanosomiasis are neglected tropical diseases and are a heavy burden in Latin America and Africa, respectively. Chagas disease is an independent risk factor for stroke. Apical aneurysm, heart failure and cardiac arrhythmias are associated with ischemic stroke in chagasic cardiomyopathy. Not all chagasic patients who suffer an ischemic stroke have a severe cardiomyopathy, and stroke may be the first manifestation of Chagas disease. Cardioembolism affecting the middle cerebral artery is the most common stroke subtype. Risk of recurrence is high and careful evaluation of recurrence risk should be addressed. Repolarization changes, low voltage and prolonged QT interval are common electrocardiography alterations in human African trypanosomiasis, and can be found in more than 70% of patients. Epidemiological studies are needed to asses the risk of stroke in African trypanosomiasis perimyocarditis.
Collapse
|
35
|
Abstract
Human African trypanosomiasis (sleeping sickness) occurs in sub-Saharan Africa. It is caused by the protozoan parasite Trypanosoma brucei, transmitted by tsetse flies. Almost all cases are due to Trypanosoma brucei gambiense, which is indigenous to west and central Africa. Prevalence is strongly dependent on control measures, which are often neglected during periods of political instability, thus leading to resurgence. With fewer than 12 000 cases of this disabling and fatal disease reported per year, trypanosomiasis belongs to the most neglected tropical diseases. The clinical presentation is complex, and diagnosis and treatment difficult. The available drugs are old, complicated to administer, and can cause severe adverse reactions. New diagnostic methods and safe and effective drugs are urgently needed. Vector control, to reduce the number of flies in existing foci, needs to be organised on a pan-African basis. WHO has stated that if national control programmes, international organisations, research institutes, and philanthropic partners engage in concerted action, elimination of this disease might even be possible.
Collapse
Affiliation(s)
- Reto Brun
- Swiss Tropical Institute, Basel, Switzerland.
| | | | | | | |
Collapse
|
36
|
Ben Zirar S, Astier A, Muchow M, Gibaud S. Comparison of nanosuspensions and hydroxypropyl-β-cyclodextrin complex of melarsoprol: Pharmacokinetics and tissue distribution in mice. Eur J Pharm Biopharm 2008; 70:649-56. [DOI: 10.1016/j.ejpb.2008.05.012] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2007] [Revised: 05/17/2008] [Accepted: 05/23/2008] [Indexed: 11/25/2022]
|
37
|
Abstract
In contrast with more common dementing conditions that typically develop over years, rapidly progressive dementias can develop subacutely over months, weeks, or even days and be quickly fatal. Because many rapidly progressive dementias are treatable, it is paramount to evaluate and diagnose these patients quickly. This review summarizes recent advances in the understanding of the major categories of RPD and outlines efficient approaches to the diagnosis of the various neurodegenerative, toxic-metabolic, infectious, autoimmune, neoplastic, and other conditions that may progress rapidly.
Collapse
Affiliation(s)
- Michael D Geschwind
- University of California San Francisco Memory & Aging Center, Department of Neurology, San Francisco, CA 94143-1207, USA.
| | | | | | | | | |
Collapse
|
38
|
Human African trypanosomiasis: pharmacological re-engagement with a neglected disease. Br J Pharmacol 2007; 152:1155-71. [PMID: 17618313 DOI: 10.1038/sj.bjp.0707354] [Citation(s) in RCA: 221] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
This review discusses the challenges of chemotherapy for human African trypanosomiasis (HAT). The few drugs registered for use against the disease are unsatisfactory for a number of reasons. HAT has two stages. In stage 1 the parasites proliferate in the haemolymphatic system. In stage 2 they invade the central nervous system and brain provoking progressive neurological dysfunction leading to symptoms that include the disrupted sleep wake patterns that give HAT its more common name of sleeping sickness. Targeting drugs to the central nervous system offers many challenges. However, it is the cost of drug development for diseases like HAT, that afflict exclusively people of the world's poorest populations, that has been the principal barrier to new drug development and has led to them becoming neglected. Here we review drugs currently registered for HAT, and also discuss the few compounds progressing through clinical trials. Finally we report on new initiatives that might allow progress to be made in developing new and satisfactory drugs for this terrible disease.
Collapse
|
39
|
Clement B, Bürenheide A, Rieckert W, Schwarz J. Diacetyldiamidoximeester of pentamidine, a prodrug for treatment of protozoal diseases: synthesis, in vitro and in vivo biotransformation. ChemMedChem 2007; 1:1260-7. [PMID: 17001612 DOI: 10.1002/cmdc.200600079] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Pentamidine is an effective antimicrobial agent. To increase its poor oral bioavailability due to the strong basic amidine functionality, the less basic O-acetylamidoxime prodrug, the diacetyldiamidoximeester, was used, which has greatly improved lipophilicity. The objectives of this investigation were the synthesis of all potential metabolites of the double prodrug, the conformational analysis of its structure, and to study the in vitro and in vivo biotransformation by ester cleavage and N-reduction to pentamidine via four intermediate metabolites. The biotransformation of diacetyldiamidoximeester to pentamidine involving the reduction of the amidoxime function and the ester cleavage could be demonstrated. The kinetic parameters were determined. Amidoximes were efficiently metabolized by several enzyme systems located in microsomes and mitochondria of different organs including the final formation of the active metabolite pentamidine. The formation of pentamidine after oral administration of the diacetyldiamidoximeester to rats could be demonstrated as well.
Collapse
Affiliation(s)
- Bernd Clement
- Pharmazeutisches Institut, Christian-Albrechts-Universität Kiel, Gutenbergstrasse 76, 24118 Kiel, Germany.
| | | | | | | |
Collapse
|