1
|
Terto WDS, Moura MQD, Borchardt JL, Santos FDS, Avila LFDC, Pinheiro NB, Leite FPL, Villela MM, Berne MEA. Cyclosporine A increases the intensity of Toxocara canis infection in swiss mice. BRAZ J BIOL 2022; 82:e260199. [PMID: 36134869 DOI: 10.1590/1519-6984.260199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 06/18/2022] [Indexed: 11/22/2022] Open
Abstract
Toxocariasis is a zoonotic disease of worldwide distribution. The connection between parasitic diseases and conditions that depress the immune system, such as the use of immunosuppressive drugs, has been studied. The purpose of this study was to evaluate the effect of Cyclosporine A (CsA) on the intensity of infection, humoral response and gene transcription of interleukins IL-4, IL-10 and IL-12 in mice experimentally infected with Toxocara canis. To this end, mice were divided into two groups treated with CsA (G1: 10 mg/Kg and G2: 50 mg/kg), the G3 and G4 group received PBS. After the last administration of the drug or PBS (orally every 48 hours for 15 days), groups G1, G2 and G3 were inoculated with 1200 eggs of T. canis. Was collected blood samples on days zero, 15 and 30 days post-inoculation (PI), for ELISA test and the mice were euthanized 30 days PI. The organs and striated muscle tissue were collected for the recovery of larvae. The splenocytes were analyzed by RT-PCR. The intensity of infection in the mice treated with 50 mg/kg of CsA was 65.5% higher than in the control group (p=0.001). An analysis of the kinetics of anti-Toxocara antibody revealed that the groups treated with CsA showed significantly higher mean levels of antibodies on day 15 PI. The transcription of the three tested interleukins showed no statistical difference between G2 and G3 (control). It was concluded that the immunosuppression triggered by CsA (50 mg/Kg) favored the establishment of a larger number of T. canis larvae without, however, altering immunoglobulin production and IL-4, IL-10 and IL-12 transcription on day 30 PI.
Collapse
Affiliation(s)
- W D S Terto
- Universidade Federal de Pelotas - UFPel, Institute of Biology, Department of Microbiology and Parasitology, Post-Graduate Program in Microbiology and Parasitology, University Campus of Capão do Leão, Pelotas, RS, Brasil
| | - M Q de Moura
- Universidade Federal de Pelotas - UFPel, Institute of Biology, Department of Microbiology and Parasitology, Post-Graduate Program in Microbiology and Parasitology, University Campus of Capão do Leão, Pelotas, RS, Brasil
| | - J L Borchardt
- Universidade Federal de Pelotas - UFPel, Institute of Biology, Department of Microbiology and Parasitology, Post-Graduate Program in Microbiology and Parasitology, University Campus of Capão do Leão, Pelotas, RS, Brasil
| | - F D S Santos
- Universidade Federal de Pelotas - UFPel, Institute of Biology, Department of Microbiology and Parasitology, Post-Graduate Program in Microbiology and Parasitology, University Campus of Capão do Leão, Pelotas, RS, Brasil
| | - L F da Costa Avila
- Universidade Federal do Rio Grande - FURG, Faculty of Medicine, Academic Area of the University Hospital, Post-Graduate Program in Health Sciences - Parasitology Laboratory, Rio Grande, RS, Brasil
| | - N B Pinheiro
- Universidade Federal de Pelotas - UFPel, Institute of Biology, Department of Microbiology and Parasitology, Post-Graduate Program in Microbiology and Parasitology, University Campus of Capão do Leão, Pelotas, RS, Brasil
| | - F P Leivas Leite
- Universidade Federal de Pelotas - UFPel, Biotechnology Center, Post-Graduate Program in biotechnology, University Campus of Capão do Leão, Pelotas, RS, Brasil
| | - M M Villela
- Universidade Federal de Pelotas - UFPel, Institute of Biology, Department of Microbiology and Parasitology, Post-Graduate Program in Microbiology and Parasitology, University Campus of Capão do Leão, Pelotas, RS, Brasil
| | - M E A Berne
- Universidade Federal de Pelotas - UFPel, Institute of Biology, Department of Microbiology and Parasitology, Post-Graduate Program in Microbiology and Parasitology, University Campus of Capão do Leão, Pelotas, RS, Brasil
| |
Collapse
|
2
|
Infection by Trypanosoma cruzi in the central nervous system in non-human mammals: a systematic review. Parasitology 2019; 146:983-1005. [PMID: 30873928 DOI: 10.1017/s0031182019000210] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Currently, the types and distribution of the lesions induced in the central nervous system (CNS) by Trypanosoma cruzi remain unclear as the available evidence is based on fragmented data. Therefore, we developed a systematic review to analyse the main characteristics of the CNS lesions in non-human hosts infected. From a structured search on the PubMed/Medline and Scopus platforms, 32 studies were retrieved, subjected to data extraction and methodological bias analysis. Our results show that the most frequent alterations in the CNS are the presence of different forms of T. cruzi and intense lymphocytes infiltrates. The encephalon is the main target of T. cruzi, and inflammatory changes in the CNS are more frequent and severe in the acute phase of infection. The parasite's genotype and phenotype are associated with the tropism and severity of the CNS lesions. The methodological limitations found in the studies were divergences in inoculation pathways, under-reporting of animal age and weight, sample calculation strategies and histopathological characterization. Since the changes were dependent on the pathogenicity and virulence of the T. cruzi strains, the genotype and phenotype characterization of the parasite are extremely relevant to predict changes in the CNS and the neurological manifestations associated with Chagas' disease.
Collapse
|
3
|
Scarim CB, de Andrade CR, da Rosa JA, dos Santos JL, Chin CM. Hydroxymethylnitrofurazone treatment in indeterminate form of chronic Chagas disease: Reduced intensity of tissue parasitism and inflammation-A histopathological study. Int J Exp Pathol 2018; 99:236-248. [PMID: 30320480 PMCID: PMC6302791 DOI: 10.1111/iep.12289] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2017] [Revised: 07/25/2018] [Accepted: 08/06/2018] [Indexed: 12/24/2022] Open
Abstract
Hydroxymethylnitrofurazone (NFOH) is a nitrofurazone prodrug effective in vivo during acute infections, and it has less hepatotoxicity effect than the standard drug benznidazole (BZN) which has been used during short- and long-term treatment. In the present study, we induced the indeterminate form of Chagas disease in mice with a Y strain of Trypanosoma cruzi and analysed the histopathological data about the effects of NFOH and BZN on different tissues, including the heart, skeletal muscle, liver, kidney, colon, spleen and brain. After infection, BALB/c mice were treated with NFOH (150 mg/kg) and BZN (60 mg/kg) for 60 days and then submitted to immunosuppression using dexamethasone (5 mg/kg) for 14 days. Two trained analysts, as part of a blind evaluation, examined the results using serial sections of 3 mm diameter in two different moments. The results showed reactivation of the disease only in the infected nontreated group (POS). After treatment, amastigote nests were found in the heart, colon, liver and skeletal muscle in the POS group and in the heart and liver of the BZN group. Interestingly, amastigote nests were not found in the NFOH and NEG groups. The histopathological analysis showed fewer tissue lesions and parasite infiltrates in the NFOH group when compared with the BZN and POS groups. We have not observed any increase in the levels of hepatocellular injury biomarkers (AST/ALT) in the NFOH group. These in vivo studies show the potential for NFOH as an effective and safe compound useful as an anti-T. cruzi agent.
Collapse
Affiliation(s)
- Cauê B. Scarim
- São Paulo State University (UNESP)School of Pharmaceutical SciencesDepartment of Drugs and MedicinesLapdesf ‐ Laboratory of Research and Development of DrugsAraraquaraSão PauloBrazil
| | - Cleverton R. de Andrade
- São Paulo State University (UNESP)Faculty of DentistryDepartment of Physiology and PathologyAraraquaraSão PauloBrazil
| | - João A. da Rosa
- São Paulo State University (UNESP)School of Pharmaceutical SciencesDepartment of Biological SciencesAraraquaraSão PauloBrazil
| | - Jean L. dos Santos
- São Paulo State University (UNESP)School of Pharmaceutical SciencesDepartment of Drugs and MedicinesLapdesf ‐ Laboratory of Research and Development of DrugsAraraquaraSão PauloBrazil
| | - Chung M. Chin
- São Paulo State University (UNESP)School of Pharmaceutical SciencesDepartment of Drugs and MedicinesLapdesf ‐ Laboratory of Research and Development of DrugsAraraquaraSão PauloBrazil
| |
Collapse
|
4
|
Scarim CB, Jornada DH, Chelucci RC, de Almeida L, Dos Santos JL, Chung MC. Current advances in drug discovery for Chagas disease. Eur J Med Chem 2018; 155:824-838. [PMID: 30033393 DOI: 10.1016/j.ejmech.2018.06.040] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Revised: 06/14/2018] [Accepted: 06/15/2018] [Indexed: 12/29/2022]
Abstract
Chagas disease, also known as American trypanosomiasis, is one of the 17 neglected tropical diseases (NTDs) according to World Health Organization. It is estimated that 8-10 million people are infected worldwide, mainly in Latin America. Chagas disease is caused by the parasite Trypanosoma cruzi and is characterized by two phases: acute and chronic. The current therapy for Chagas disease is limited to drugs such as nifurtimox and benznidazole, which are effective in treating only the acute phase of the disease. In addition, several side effects ranging from hypersensitivity to bone marrow depression and peripheral polyneuropathy have been associated with these drugs. Therefore, the current challenge is to find new effective and safe drugs against this NTD. The aim of this review is to describe the advances in the medicinal chemistry of new anti-chagasic compounds reported in the literature in the last five years. We report promising prototypes for drug discovery identified through target-based and phenotype-based strategies and present some important targets for the development of new synthetic compounds.
Collapse
Affiliation(s)
- Cauê Benito Scarim
- Departamento de Fármacos e Medicamentos, Faculdade de Ciências Farmacêuticas, Universidade Estadual Paulista "Júlio de Mesquita Filho", UNESP, Araraquara, SP, Brazil.
| | - Daniela Hartmann Jornada
- Departamento de Fármacos e Medicamentos, Faculdade de Ciências Farmacêuticas, Universidade Estadual Paulista "Júlio de Mesquita Filho", UNESP, Araraquara, SP, Brazil
| | - Rafael Consolin Chelucci
- Departamento de Fármacos e Medicamentos, Faculdade de Ciências Farmacêuticas, Universidade Estadual Paulista "Júlio de Mesquita Filho", UNESP, Araraquara, SP, Brazil
| | - Leticia de Almeida
- Departamento de Biologia Celular e Molecular, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, USP, Brazil
| | - Jean Leandro Dos Santos
- Departamento de Fármacos e Medicamentos, Faculdade de Ciências Farmacêuticas, Universidade Estadual Paulista "Júlio de Mesquita Filho", UNESP, Araraquara, SP, Brazil
| | - Man Chin Chung
- Departamento de Fármacos e Medicamentos, Faculdade de Ciências Farmacêuticas, Universidade Estadual Paulista "Júlio de Mesquita Filho", UNESP, Araraquara, SP, Brazil
| |
Collapse
|
5
|
Scarim CB, Ribeiro AR, Rosa JAD, Chin CM. Response to different benznidazole doses in animal models of chronic phase Chagas disease: a critical review. Rev Soc Bras Med Trop 2018; 51:133-140. [DOI: 10.1590/0037-8682-0337-2017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Accepted: 04/18/2018] [Indexed: 01/23/2023] Open
Affiliation(s)
| | | | | | - Chung Man Chin
- Universidade Estadual Paulista Júlio de Mesquita Filho, Brazil
| |
Collapse
|
6
|
Söllner J, Mayer P, Heinzel A, Fechete R, Siehs C, Oberbauer R, Mayer B. Synthetic lethality for linking the mycophenolate mofetil mode of action with molecular disease and drug profiles. MOLECULAR BIOSYSTEMS 2012; 8:3197-207. [DOI: 10.1039/c2mb25256b] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
7
|
Abstract
Immune compromise can modify the severity and manifestation of some parasitic infections. More widespread use of newer immnosuppressive therapies, the growing population of individuals with immunocompromised states as well as the prolonged survival of these patients have altered the pattern of parasitic infection. This review article discusses the burden and immunology of parasitic infections in patients who are immunocompromised secondary to congenital immunodeficiency, malnutrition, malignancy, and immunosuppressive medications. This review does not address the literature on parasitic infections in the setting of HIV-1 infection.
Collapse
Affiliation(s)
- T Evering
- Department of Medicine (Division of Infectious Diseases), Albert Einstein College of Medicine, Bronx, New York 10461, USA
| | | |
Collapse
|
8
|
Taniwaki NN, Andreoli WK, Calabrese KS, da Silva S, Mortara RA. Disruption of myofibrillar proteins in cardiac muscle of Calomys callosus chronically infected with Trypanosoma cruzi and treated with immunosuppressive agent. Parasitol Res 2005; 97:323-31. [PMID: 16075261 DOI: 10.1007/s00436-005-1429-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2004] [Accepted: 06/02/2005] [Indexed: 10/25/2022]
Abstract
Calomys callosus (Rodentia: Cricetidae) chronically infected with CL strain of Trypanosoma cruzi undergo recrudescence of the acute phase when treated with the immunosuppressor cyclophosphamide. The distribution of cytoskeletal proteins in cardiac tissue of immunosuppressed animals was mapped by immunofluorescence and electron microscopy to evaluate myofibrillar distribution during the intracellular life cycle of T. cruzi. Cardiac muscle sections showed enhancement of myocarditis and parasite proliferation after immunosuppression. Immunofluorescence using monoclonal antibodies against myosin, actin, desmin, titin, tropomyosin, and troponin T demonstrated disruption and loss of contractile proteins, such as myosin and actin. Desmin and titin were irregularly distributed in close proximity to parasite nests. Ultrastructural observations confirmed alterations of cardiac cells with Z-line fragmentation, indistinguishable I-bands and A-bands, and loss of myofibrillar elements. The disruption of the muscle cell architecture was greater as infection progressed, probably as a result of increased myocarditis and physical displacement due to the activity of flagellated parasites.
Collapse
Affiliation(s)
- Noemi N Taniwaki
- Seção de Microscopia Eletrônica, Instituto Adolfo Lutz, Av. Dr. Arnaldo 355, 01246-902 São Paulo, SP, Brazil
| | | | | | | | | |
Collapse
|
9
|
Marino APMP, Silva AA, Santos PVA, Pinto LMO, Gazinelli RT, Teixeira MM, Lannes-Vieira J. CC-chemokine receptors: a potential therapeutic target for Trypanosoma cruzi-elicited myocarditis. Mem Inst Oswaldo Cruz 2005; 100 Suppl 1:93-6. [PMID: 15962104 DOI: 10.1590/s0074-02762005000900015] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The comprehension of the pathogenesis of Trypanosoma cruzi-elicited myocarditis is crucial to delineate new therapeutic strategies aiming to ameliorate the inflammation that leads to heart dysfunction, without hampering parasite control. The augmented expression of CCL5/RANTES and CCL3/MIP-1alpha, and their receptor CCR5, in the heart of T. cruzi-infected mice suggests a role for CC-chemokines and their receptors in the pathogenesis of T. cruzi-elicited myocarditis. Herein, we discuss our recent results using a CC-chemokine receptor inhibitor (Met-RANTES), showing the participation of CC-chemokines in T. cruzi infection and unraveling CC-chemokine receptors as an attractive therapeutic target for further evaluation in Chagas disease.
Collapse
Affiliation(s)
- A P M P Marino
- Laboratório de Autoimunidade e Imuno-regulação, Departamento de Imunologia, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro, RJ, 21040-900, Brasil
| | | | | | | | | | | | | |
Collapse
|
10
|
Bilate AMB, Salemi VMC, Ramires FJA, de Brito T, Silva AM, Umezawa ES, Mady C, Kalil J, Cunha-Neto E. The Syrian hamster as a model for the dilated cardiomyopathy of Chagas’ disease: a quantitative echocardiographical and histopathological analysis. Microbes Infect 2003; 5:1116-24. [PMID: 14554253 DOI: 10.1016/j.micinf.2003.07.001] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Chronic Chagas' disease cardiomyopathy (CCC) is caused by the protozoan Trypanosoma cruzi, and it affects 30% of the 16-18 million people infected in Latin America. A good rodent model that develops a dilated cardiomyopathy closely resembling human CCC after T. cruzi infection is still needed. We compared the cardiomyopathy developed by T. cruzi-infected Syrian hamsters with human Chagas' disease cardiomyopathy using quantitative methods. Female hamsters were infected with 3.5 x 10(4) (G1, n = 10) or 10(5) (G2, n = 10) T. cruzi Y strain blood trypomastigotes. Control animals (C, n = 10) were injected with saline solution. Cardiac function was assessed by echocardiography at 4, 8 and 12 months post-infection. Heart sections were submitted to histopathological/morphometric analysis 12 months post-infection. At this time, ventricular dysfunction and diffuse or multi-focal myocarditis were observed in 91% and 100% of G1 and G2 infected groups, respectively. Median interstitial collagen volumes in groups C, G1 and G2 were 1.2%, 1.9% and 3.9%, respectively, and were significantly higher in group G2 than in group C. Among infected animals, myocarditis showed a positive correlation with interstitial fibrosis. Deaths in the chronic phase (8-12 months post-infection) were more frequent among G2 than G1, and were associated with macroscopic ventricular dilation, severe myocarditis and increased fibrosis values, along with an earlier onset of ventricular dysfunction. The T. cruzi chronically infected Syrian hamster develops a cardiomyopathy which resembles human Chagas' disease cardiomyopathy, and might be an adequate tool to investigate pathogenic mechanisms of this disease and to search for novel therapeutic strategies.
Collapse
Affiliation(s)
- Angelina M B Bilate
- Laboratory of Immunology, Heart Institute (Incor), University of São Paulo Medical School, Av. Dr. Enéas de Carvalho Aguiar, 44-Bloco II-90 andar, 05403-000 Sao Paulo, SP, Brazil
| | | | | | | | | | | | | | | | | |
Collapse
|
11
|
Roffê E, Silva AA, Marino APMP, dos Santos PVA, Lannes-Vieira J. Essential role of VLA-4/VCAM-1 pathway in the establishment of CD8+ T-cell-mediated Trypanosoma cruzi-elicited meningoencephalitis. J Neuroimmunol 2003; 142:17-30. [PMID: 14512161 DOI: 10.1016/s0165-5728(03)00254-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Central nervous system (CNS) damage can occur during Trypanosoma cruzi infection, especially in immunosuppressed patients. The enhanced susceptibility of C3H/He mice to CD8-mediated acute meningoencephalitis is associated with higher up-regulation of vascular cell adhesion molecule-1 (VCAM-1) on CNS vascular endothelia than in the less susceptible C57BL/6. Further, in vitro adhesion of activated peripheral blood cells to CNS blood vessels was abrogated by anti-VLA-4 antibodies that also inhibited cell migration into the CNS of T. cruzi-infected mice. Lastly, the reactivation of meningoencephalitis in immunosuppressed chronically infected mice was associated with VCAM-1 up-regulation. Therefore, we hypothesize that VLA-4/VCAM-1 pathway plays a pivotal role in the establishment of T. cruzi-elicited encephalitis.
Collapse
MESH Headings
- Animals
- Antigens, Protozoan/analysis
- CD8-Positive T-Lymphocytes/immunology
- CD8-Positive T-Lymphocytes/parasitology
- Cell Adhesion/immunology
- Cell Movement/immunology
- Central Nervous System Protozoal Infections/immunology
- Central Nervous System Protozoal Infections/metabolism
- Central Nervous System Protozoal Infections/parasitology
- Central Nervous System Protozoal Infections/pathology
- Chagas Disease/immunology
- Chagas Disease/metabolism
- Chagas Disease/parasitology
- Chagas Disease/pathology
- Chronic Disease
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/immunology
- Endothelium, Vascular/parasitology
- Endothelium, Vascular/pathology
- Female
- Genetic Predisposition to Disease
- Immunophenotyping
- Immunosuppressive Agents/administration & dosage
- Integrin alpha4beta1/biosynthesis
- Integrin alpha4beta1/physiology
- Intercellular Adhesion Molecule-1/biosynthesis
- Leukocytes, Mononuclear/chemistry
- Leukocytes, Mononuclear/immunology
- Leukocytes, Mononuclear/parasitology
- Meningoencephalitis/immunology
- Meningoencephalitis/metabolism
- Meningoencephalitis/parasitology
- Meningoencephalitis/pathology
- Mice
- Mice, Inbred C3H
- Mice, Inbred C57BL
- Recurrence
- Signal Transduction/immunology
- Trypanosoma cruzi/immunology
- Vascular Cell Adhesion Molecule-1/biosynthesis
- Vascular Cell Adhesion Molecule-1/physiology
Collapse
Affiliation(s)
- Ester Roffê
- Laboratório de Autoimunidade e Imuno-regulação, Departamento de Imunologia, Instituto Oswaldo Cruz-Fundação Oswaldo Cruz, Av. Brasil, 4365 Rio de Janeiro, RJ 21045-900, Brazil
| | | | | | | | | |
Collapse
|
12
|
Andrade SG, Mesquita IMO, Jambeiro JF, Santos IFM, Portella RS. Treatment with benznidazole in association with immunosuppressive drugs in mice chronically infected with Trypanosoma cruzi: investigation into the possible development of neoplasias. Rev Soc Bras Med Trop 2003; 36:441-7. [PMID: 12937719 DOI: 10.1590/s0037-86822003000400002] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Benznidazole is recommended in Brazil for the treatment of Trypanosoma cruzi infection in acute and early chronic phases of Chagas' disease. Observations by others have indicated a higher incidence of neoplasias in immunosuppressed patients, presenting Chagas' disease reactivation, submitted to treatment with benznidazole. In the present study, we investigated whether there is a potentiation in the generation of lymphomas in chronically infected mice, treated with immunosuppressive drugs and benznidazole. For this, 142 Swiss mice chronically infected with the 21 SF strain of T. cruzi and 72 normal Swiss mice were used. Both infected and normal mice were divided into experimental groups and submitted to one of the following treatment regimens: benznidazole alone; immunosuppressive drugs (azathioprine, betamethasone and cyclosporin); a combination of immunosuppressive drugs and benznidazole; and untreated controls. In the infected group treated with benznidazole, one mouse developed a non-Hodgkin's lymphoma. This finding has been interpreted as a spontaneous tumor of mice. The study of the chronically infected mice treated with the combination of immunosuppressive drugs and benznidazole demonstrated an absence of lymphomas or other neoplasias. These findings support the indication of benznidazole, as the drug of choice, for immunosuppressed patients that develop a reactivation of Chagas' disease.
Collapse
Affiliation(s)
- Sonia G Andrade
- Laboratório de Doença de Chagas Experimental, Centro de Pesquisas Gonçalo Moniz, Fundação Oswaldo Cruz, Salvador, BA, Brasil
| | | | | | | | | |
Collapse
|
13
|
Abstract
Two primary hypotheses are proposed to account for pathogenesis in chronic Trypanosoma cruzi infections: that the persistence of T. cruzi at specific sites in the infected host results in chronic inflammatory reactivity and that T. cruzi infection induces immune responses which are targetted at self tissues. The data supporting parasite persistence as the primary cause of disease in T. cruzi infection have been recently reviewed and the reader is referred to this review for extensive documentation of most of the arguments outlined herein. This manuscript will briefly reiterate the main points of this previous review, adding additional data that have been presented since its publication. Then, philosophical and practical arguments on why Chagas disease should be investigated and treated as a parasitic infection and not as an autoimmune disease are presented. This is admittedly an 'opinion piece' and not a balanced review of the literature on Chagas disease. There are substantial data other than those reviewed here, which have been presented in support of the autoimmunity hypothesis. It is left to others to review that body of literature.
Collapse
Affiliation(s)
- R L Tarleton
- Department of Cellular Biology and Center for Tropical and Emerging Global Diseases, University of Georgia, 30602, Athens, GA, USA.
| |
Collapse
|
14
|
Michailowsky V, Murta SM, Carvalho-Oliveira L, Pereira ME, Ferreira LR, Brener Z, Romanha AJ, Gazzinelli RT. Interleukin-12 enhances in vivo parasiticidal effect of benznidazole during acute experimental infection with a naturally drug-resistant strain of Trypanosoma cruzi. Antimicrob Agents Chemother 1998; 42:2549-56. [PMID: 9756754 PMCID: PMC105888 DOI: 10.1128/aac.42.10.2549] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The roles of gamma interferon (IFN-gamma) and interleukin-12 (IL-12) in mediating and/or enhancing the in vivo trypanosomicidal activity of the nitroheterocyclic derivative benznidazole (Bz) were evaluated during early stages of experimental Chagas' disease. Our results show that treatment of Trypanosoma cruzi-infected mice with anti-cytokine monoclonal antibodies (MAbs) had no apparent effect when the optimal dose of Bz (100 mg/kg of body weight) was used. In contrast, treatment with anti-IL-12 or anti-IFN-gamma MAbs enhanced the parasitemia and accelerated the mortality of mice treated with a suboptimal dose of Bz (25 mg/kg). Simultaneous treatment with a suboptimal dose of Bz and recombinant IL-12 (rIL-12) enhanced the efficacy of drug treatment in terms of parasitemia and mouse survival. Interestingly, we found that drug-resistant T. cruzi strains were found to be poor inducers of IL-12 both in vitro and in vivo compared to strains of T. cruzi which are susceptible or partially resistant to Bz treatment. These results suggest that early activation of the cellular compartment of the immune system by IL-12 may favor in vivo Bz activity against T. cruzi. In order to test this hypothesis mice infected with the drug-resistant Colombiana strain of T. cruzi were treated with 100 mg of Bz per kg plus different concentrations of rIL-12. By using the results of PCR and serological and parasitological methods as the criteria of a cure, our results indicate that a higher percentage of mice treated with Bz combined with rIL-12 than mice treated with Bz alone are cured.
Collapse
Affiliation(s)
- V Michailowsky
- Department of Biochemistry and Immunology, Federal University of Minas Gerais, 30270-010 Belo Horizonte, MG, Centro de Pesquisas René Rachou, Oswaldo Cruz Foundation, 30190-002 Belo Horizonte, MG, Brazil
| | | | | | | | | | | | | | | |
Collapse
|