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Gustavo Fortunato,
Daniel Ta Vidal,
Wilfried Klein,
Alberto Neto,
André Angrizani,
Juliana F Vasconcelos,
Carla Kaneto,
Bruno Solano de Freitas Souza,
Ricardo Ribeiro-Dos-Santos, Milena B P Soares,
Simone G Macambira
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ABSTRACT: Emphysema is a chronic obstructive pulmonary disease characterized abnormal dilatation of alveolar spaces, which impairs alveolar gas exchange, compromising the physical capacity of a patient due to airflow limitations. Here we tested the effects of G-CSF administration in pulmonary tissue and exercise capacity in emphysematous mice. C57Bl/6 female mice were treated with elastase intratracheally to induce emphysema. Their exercise capacities were evaluated in a treadmill. Lung histological sections were prepared to evaluate mean linear intercept measurement. Emphysematous mice were treated with G-CSF (3 cycles of 200 μg/kg/day for 5 consecutive days, with 7-day intervals) or saline and submitted to a third evaluation 8 weeks after treatment. Values of run distance and linear intercept measurement were expressed as mean ± SD and compared applying a paired t-test. Effects of treatment on these parameters were analyzed applying a Repeated Measures ANOVA, followed by Tukey's post hoc analysis. p<0.05 was considered statistically significant. Twenty eight days later, animals ran significantly less in a treadmill compared to normal mice (549.7±181.2 m and 821.7±131.3 m, respectively; p<0.01). Treatment with G-CSF significantly increased the exercise capacity of emphysematous mice (719.6±200.5 m), whereas saline treatment had no effect on distance run (595.8±178.5 m). The PCR cytokines genes analysis did not detect difference between experimental groups. Morphometric analyses in the lung showed that saline-treated mice had a mean linear intersept significantly higher (p<0.01) when compared to mice treated with G-CSF, which did not significantly differ from that of normal mice. Treatment with G-CSF promoted the recovery of exercise capacity and regeneration of alveolar structural alterations in emphysematous mice.
Pulmonary Pharmacology & Therapeutics 04/2013; · 2.80 Impact Factor
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ABSTRACT: Approximately 30% of patients with mesial temporal lobe epilepsy do not respond to treatment with antiepileptic drugs. We have previously shown that transplantation of mononuclear bone marrow cells (BMC) has an anticonvulsant effect in acute epilepsy. Here, we used pilocarpine to induce epilepsy in rats and studied the effects of BMC injected intravenously either at the onset of seizures or after 10months of recurrent seizures. BMC effectively decreased seizure frequency and duration. In addition, decreased levels of proinflammatory cytokines (TNF-$alpha$, IL-1$beta$ and IL-6) and increased levels of anti-inflammatory cytokine (IL-10) were observed in the brain and serum of BMC-treated rats. Transplants performed at seizure-onset protected against pilocarpine-induced neuronal loss and gliosis and stimulated the proliferation of new neurons in epileptic rats. Our data demonstrate that BMC transplantation has potent therapeutic effects and could be a potential therapy for clinically intractable epilepsies.
Neurobiology of Disease 12/2011; · 5.40 Impact Factor
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ABSTRACT: The antimalarial activities of physalins B, D, F, and G (1-4), isolated from Physalis angulata, were investigated. In silico analysis using the similarity ensemble approach (SEA) database predicted the antimalarial activity of each of these compounds, which were shown using an in vitro assay against Plasmodium falciparum. However, treatment of P. berghei-infected mice with 3 increased parasitemia levels and mortality, whereas treatment with 2 was protective, causing a parasitemia reduction and a delay in mortality in P. berghei-infected mice. The exacerbation of in vivo infection by treatment with 3 is probably due to its potent immunosuppressive activity, which is not evident for 2.
Journal of Natural Products 09/2011; 74(10):2269-72. · 3.13 Impact Factor
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Milena B P Soares,
Ricardo S Lima,
Bruno S F Souza,
Juliana F Vasconcelos,
Leonardo L Rocha,
Ricardo Ribeiro Dos Santos,
Sanda Iacobas,
Regina C Goldenberg,
Michael P Lisanti,
Dumitru A Iacobas,
Herbert B Tanowitz,
David C Spray,
Antonio C Campos de Carvalho
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ABSTRACT: Chronic chagasic cardiomyopathy is a leading cause of heart failure in Latin American countries, being associated with intense inflammatory response and fibrosis. We have previously shown that bone marrow mononuclear cell (BMC) transplantation improves inflammation, fibrosis, and ventricular diameter in hearts of mice with chronic Chagas disease. Here we investigated the transcriptomic recovery induced by BMC therapy by comparing the heart transcriptomes of control, chagasic, and BMC transplanted mice. Out of the 9390 unique genes quantified in all samples, 1702 had their expression altered in chronic chagasic hearts compared to those of normal mice. Major categories of significantly upregulated genes were related to inflammation, fibrosis and immune responses, while genes involved in mitochondrion function were downregulated. When BMC-treated chagasic hearts were compared to infected mice, 96% of the alterations detected in infected hearts were restored to normal levels, although an additional 109 genes were altered by treatment. Transcriptomic recovery, a new measure that considers both resotrative and side effects of treatment, was remarkably high (84%). Immunofluorescence and morphometric analyses confirmed the effects of BMC therapy in the pattern of inflammatory-immune response and expression of adhesion molecules. In conclusion, by using large-scale gene profiling for unbiased assessment of therapeutic efficacy we demonstrate immunomodulatory effects of BMC therapy in chronic chagasic cardiomyopathy and identify potentially relevant factors involved in the pathogenesis of the disease that may provide new therapeutic targets.
Cell cycle (Georgetown, Tex.) 05/2011; 10(9):1448-55. · 5.36 Impact Factor
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ABSTRACT: Heart failure due to Chagas' disease (HFCD) is a progressive inflammatory cardiomyopathy that affects millions of individuals in Latin America. Studies using mice models of HFCD indicate that bone marrow mononuclear cell transplantation (BMCT) may reduce inflammation, fibrosis, and improve myocardial function.
The purpose of this study was to evaluate, for the first time in humans, the safety and efficacy of BMCT to the myocardium of patients with HFCD.
A total of 28 HFCD patients (mean age 52.2 ± 9.9 years) with NYHA class III and IV were submitted to BMCT through intracoronary injection. Effects on the left ventricle ejection fraction (LVEF), functional capacity, quality-of-life, arrhythmias, biochemical, immunological, and neuro-humoral parameters, were evaluated.
There were no complications directly related to the procedure. LVEF was 20.1 ± 6.8% and 28.3 ± 7.9%, p < 0.03 at baseline and 180 days after the procedure, respectively. In the same period, significant improvements were observed in the NYHA class (3.1 ± 0.3 to 1.8 ± 0.5; p < 0.001), quality-of-life (50.9 ± 11.7 to 25.1 ± 15.9; p < 0.001), and in the six-minute walking test (355 ± 136 m to 437 ± 94 m; p < 0,01). There were no changes in markers of immune or neurohormonal activation. No complications were registered.
Our data suggest that the intracoronary injection of BMCT is safe and potentially effective in patients with HFCD. The extent of the benefit, however, appears to be small and needs to be confirmed in a larger randomized, double blind, placebo controlled clinical trial.
Arquivos brasileiros de cardiologia 03/2011; 96(4):325-31. · 1.32 Impact Factor
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Daniele Brustolim,
Juliana F Vasconcelos,
Luiz Antônio R Freitas,
Mauro M Teixeira,
Marcel T Farias,
Yvone M Ribeiro,
Therezinha C B Tomassini,
Geraldo G S Oliveira,
Lain C Pontes-de-Carvalho,
Ricardo Ribeiro-dos-Santos, Milena B P Soares
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ABSTRACT: The effects of physalin F (1), a steroid derivative purified from Physalis angulata, were investigated in models of collagen-induced arthritis in DBA/1 mice and allergic airway inflammation in BALB/c mice. Oral treatment with 1 or dexamethasone caused a marked decrease in paw edema and joint inflammation when compared to vehicle-treated arthritic mice. In contrast, treatment with 1 had no effect in mice with allergic airway inflammation caused by ovalbumin immunization, whereas dexamethasone significantly reduced the number of inflammatory cells and eosinophils in the broncoalveolar lavage fluid and in lung sections of challenged mice. To further demonstrate that 1 acts through a mechanism different from that of glucocorticoids, a nuclear translocation assay was performed of the glucocorticoid receptor (GR) using COS-7 cells transfected with a plasmid encoding for a yellow fluorescent protein (YFP)-GR fusion protein. Untreated or treated cells with 1 had YFP staining mainly in the cytoplasm, whereas in dexamethasone-treated cells the YFP staining was concentrated in the nuclei. It is concluded that the mechanism of the immunosuppressive activity of physalin F is distinct from that of the glucocorticoids.
Journal of Natural Products 08/2010; 73(8):1323-6. · 3.13 Impact Factor
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ABSTRACT: Objectives In the present study we investigated the antinociceptive, anti-inflammatory and antipyretic effects of 7-hydroxycoumarin (7-HC) in animal models.Methods The effects of oral 7-HC were tested against acetic acid-induced writhing, formalin test, tail flick test, complete Freund's adjuvant (CFA)-induced hypernociception, carrageenan-induced paw oedema, lipopolysaccharide-induced fever and the rota rod test.Key findings 7-HC (3–60 mg/kg) produced a dose-related antinociception against acetic acid-induced writhing in mice and in the formalin test. In contrast, treatment with 7-HC did not prevent thermal nociception in the tail flick test. A single treatment with 7-HC, 60 mg/kg, produced a long-lasting antinociceptive effect against CFA-induced hypernociception, a chronic inflammatory pain stimulus. Notably, at 60 mg/kg per day over 4 days the administration of 7-HC produced a continuous antinociceptive effect against CFA-induced hypernociception. 7-HC (30–120 mg/kg) produced anti-inflammatory and antipyretic effects against carrageenan-induced inflammation and lipopolysaccharide-induced fever, respectively. Moreover, 7-HC was found to be safe with respect to ulcer induction. In the rota rod test, 7-HC-treated mice did not show any motor performance alterations.Conclusions The prolonged antinociceptive and anti-inflammatory effects of 7-HC, in association with its low ulcerogenic activity, indicate that this molecule might be a good candidate for development of new drugs for the control of chronic inflammatory pain and fever.
Journal of Pharmacy and Pharmacology. 03/2010; 62(2):205 - 213.
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ABSTRACT: In this study, we investigated the therapeutic potential of bone marrow mononuclear cells (BMCs) in a model of epilepsy induced by pilocarpine in rats. BMCs obtained from green fluorescent protein (GFP) transgenic mice or rats were transplanted intravenously after induction of status epilepticus (SE). Spontaneous recurrent seizures (SRS) were monitored using Racine's seizure severity scale. All of the rats in the saline-treated epileptic control group developed SRS, whereas none of the BMC-treated epileptic animals had seizures in the short term (15 days after transplantation), regardless of the BMC source. Over the long-term chronic phase (120 days after transplantation), only 25% of BMC-treated epileptic animals had seizures, but with a lower frequency and duration compared to the epileptic control group. The density of hippocampal neurons in the brains of animals treated with BMCs was markedly preserved. At hippocampal Schaeffer collateral-CA1 synapses, long-term potentiation was preserved in BMC-transplanted rats compared to epileptic controls. The donor-derived GFP(+) cells were rarely found in the brains of transplanted epileptic rats. In conclusion, treatment with BMCs can prevent the development of chronic seizures, reduce neuronal loss, and influence the reorganization of the hippocampal neuronal network.
Seizure 03/2010; 19(2):84-92. · 1.80 Impact Factor
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ABSTRACT: In the present study we investigated the antinociceptive, anti-inflammatory and antipyretic effects of 7-hydroxycoumarin (7-HC) in animal models.
The effects of oral 7-HC were tested against acetic acid-induced writhing, formalin test, tail flick test, complete Freund's adjuvant (CFA)-induced hypernociception, carrageenan-induced paw oedema, lipopolysaccharide-induced fever and the rota rod test.
7-HC (3-60 mg/kg) produced a dose-related antinociception against acetic acid-induced writhing in mice and in the formalin test. In contrast, treatment with 7-HC did not prevent thermal nociception in the tail flick test. A single treatment with 7-HC, 60 mg/kg, produced a long-lasting antinociceptive effect against CFA-induced hypernociception, a chronic inflammatory pain stimulus. Notably, at 60 mg/kg per day over 4 days the administration of 7-HC produced a continuous antinociceptive effect against CFA-induced hypernociception. 7-HC (30-120 mg/kg) produced anti-inflammatory and antipyretic effects against carrageenan-induced inflammation and lipopolysaccharide-induced fever, respectively. Moreover, 7-HC was found to be safe with respect to ulcer induction. In the rota rod test, 7-HC-treated mice did not show any motor performance alterations.
The prolonged antinociceptive and anti-inflammatory effects of 7-HC, in association with its low ulcerogenic activity, indicate that this molecule might be a good candidate for development of new drugs for the control of chronic inflammatory pain and fever.
The Journal of pharmacy and pharmacology. 02/2010; 62(2):205-13.
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ABSTRACT: The ferrocenyl diphenol 1 [1,1-bis(4-hydroxyphenyl)-2-ferrocenyl-but-1-ene] displays strong cytotoxic effects against a variety of cancer cells. In the present study we have evaluated the immunomodulatory and antiparasitic activities of compound 1 and its protected dipalmitate analogue 2. We have furthermore compared the antiparasitic results of 1 and 2 with the organic analogue, 3 [1,1-bis(4-hydroxyphenyl)-2-phenyl-but-1-ene], where the ferrocenyl group has been replaced by a phenyl ring. When assayed against normal (noncancerous) splenocytes, all compounds were considered nontoxic. Compound 1 inhibited NO production by macrophages, inhibited concanavalin A-induced lymphoproliferation, and was active against Leishmania amazonensis and Trypanosoma cruzi. Compound 2 had lower activity in all assays performed. Surprisingly, compounds 1 and 2 exhibited similar and significant activity against Plasmodium falciparum, with IC50 values of 3.50 and 1.33 µM, respectively. Compound 3 showed an inverse activity profile, being active against T. cruzi but far less active against P. falciparum. Drug Dev Res 71: 69–75, 2010. © 2009 Wiley-Liss, Inc.
Drug Development Research 01/2010; 71(1):69 - 75. · 1.19 Impact Factor
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ABSTRACT: Rutaceae is a taxon with species very well distributed in Brazilian semi-arid area,
commonly used in folk medicine. Species from this genus have diverse biological activity described in literature. In this work, immunomodulatory and bactericidal activity are described for chloroform and ethyl acetate extracts of three of them (Esenbeckia grandiflora Mart., Pilocarpus spicatus A.St.-Hil. and Galipea simplicifolia Schult.). Initially all the samples had their cytotoxicity evaluated, aiming to determine the LC50. The immunomodulatory potential was evaluated in cultures of murine splenocytes stimulated or not with concanavalin A and in a mixed lymphocyte reaction (MLR) using splenocytes from BALB/c (H-2d) mice immunized with splenocytes from C57Bl/6 (H-2b) mice. Four samples had higher values of lymphoproliferation inhibition in concanavalin
A-stimulated cultures and were evaluated in MLR. The antibacterial activity of extracts as also evaluated and the minimal inhibitory concentrations (MIC) for two active samples were 1.0 and 5.0 mg/ml for extracts from Esenbeckia grandiflora Mart. and Galipea simplicifolia Schult., respectively. Thus, our results reinforce data of literature relating biological activity for many species of the Rutaceae family and encourage studies with these species aiming to discover active compounds, candidates to new medicines.
Brazilian Journal of Pharmacognosy. 01/2010; 20(4):502-505.
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ABSTRACT: This study investigates the effects of granulocyte colony-stimulating factor (G-CSF) therapy in experimental chronic chagasic cardiomyopathy. Chagas disease is one of the leading causes of heart failure in Latin America and remains without an effective treatment other than cardiac transplantation. C57BL/6 mice were infected with 10(3) trypomastigotes of Trypanosoma cruzi, and chronic chagasic mice were treated with G-CSF or saline (control). Evaluations following treatment were functional, immunological, and histopathological. Comparing hearts of G-CSF-treated mice showed reduced inflammation and fibrosis compared to saline-treated chagasic mice. G-CSF treatment did not alter the parasite load but caused an increase in the number of apoptotic inflammatory cells in the heart. Cardiac conductance disturbances in all infected animals improved or remained stable due to the G-CSF treatment, whereas all of the saline-treated mice deteriorated. The distance run on a treadmill and the exercise time were significantly greater in G-CSF-treated mice when compared to chagasic controls, as well as oxygen consumption (VO(2)), carbon dioxide production (VCO(2)), and respiratory exchange ration (RER) during exercise. Administration of G-CSF in experimental cardiac ischemia had beneficial effects on cardiac structure, which were well correlated with improvements in cardiac function and whole animal performance.
The FASEB Journal 08/2009; 23(11):3843-50. · 5.71 Impact Factor
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Filipe A Haolla,
Carla Claser,
Bruna C G de Alencar,
Fanny Tzelepis,
José Ronnie de Vasconcelos,
Gabriel de Oliveira,
Jaline C Silvério,
Alexandre V Machado,
Joseli Lannes-Vieira,
Oscar Bruna-Romero,
Ricardo T Gazzinelli,
Ricardo Ribeiro dos Santos, Milena B P Soares,
Mauricio M Rodrigues
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ABSTRACT: Immunisation with Amastigote Surface Protein 2 (asp-2) and trans-sialidase (ts) genes induces protective immunity in highly susceptible A/Sn mice, against infection with parasites of the Y strain of Trypanosoma cruzi. Based on immunological and biological strain variations in T. cruzi parasites, our goal was to validate our vaccination results using different parasite strains. Due to the importance of the CD8(+) T cells in protective immunity, we initially determined which strains expressed the immunodominant H-2K(k)-restricted epitope TEWETGQI. We tested eight strains, four of which elicited immune responses to this epitope (Y, G, Colombian and Colombia). We selected the Colombian and Colombia strains for our studies. A/Sn mice were immunised with different regimens using both T. cruzi genes (asp-2 and ts) simultaneously and subsequently challenged with blood trypomastigotes. Immune responses before the challenge were confirmed by the presence of specific antibodies and peptide-specific T cells. Genetic vaccination did not confer protective immunity against acute infection with a lethal dose of the Colombian strain. In contrast, we observed a drastic reduction in parasitemia and a significant increase in survival, following challenge with an otherwise lethal dose of the Colombia strain. In many surviving animals with late-stage chronic infection, we observed alterations in the heart's electrical conductivity, compared to naive mice. In summary, we concluded that immunity against T. cruzi antigens, similar to viruses and bacteria, may be strain-specific and have a negative impact on vaccine development.
Vaccine 08/2009; 27(41):5644-53. · 3.77 Impact Factor
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ABSTRACT: We have previously demonstrated the immunomodulatory effects of physalins, secosteroids purified from Physalis angulata. Here we investigate the antileishmanial activity of physalins in vitro and in vivo in a model of cutaneous leishmaniasis.
The antileishmanial activity of physalins B, D and F was tested in Leishmania-infected macrophage cultures. For the in vivo studies, BALB/c mice were infected with Leishmania amazonensis subcutaneously in the ear pinna and treated with physalin F by topical administration.
Physalins B and F were able to reduce the percentage of Leishmania-infected macrophages and the intracellular parasite number in vitro at concentrations non-cytotoxic to macrophages. More importantly, topical treatment with physalin F significantly reduced the lesion size, the parasite load and histopathological alterations in BALB/c mice infected with L. amazonensis.
Our results demonstrate the potent antileishmanial activity of physalins, especially physalin F, and suggest these molecules as the basis for the development of new therapeutic options for cutaneous leishmaniasis.
Journal of Antimicrobial Chemotherapy 06/2009; 64(1):84-7. · 5.07 Impact Factor
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ABSTRACT: The recent highlights on the biochemical pathways of Trypanosoma cruzi have allowed a significant improvement in the development of new strategies for drug design and also in the understanding of the mechanisms of action of new trypanocidal agents. Several biochemical pathways of fundamental importance and validated targets (e.g. cysteine protease cruzain, trypanothione reductase, trans-sialidase) of T. cruzi have proved usefulness for drug development in many examples of new candidates to anti-T. cruzi drugs. This review will focus on some approaches used for the design of new potential trypanocidal agents, exploring modern concepts of medicinal chemistry such as bioisosterism, molecular hybridization, bioinspired design in lead compounds, as well as the complexation of transition metals with bioactive ligands. The examples discussed in this article may serve as lessons for the antitrypanosomal drug design.
Current drug targets 04/2009; 10(3):212-31. · 3.93 Impact Factor
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ABSTRACT: The therapeutic effects of umbelliferone (30, 60 and 90 mg/kg), a coumarin isolated from Typha domingensis (Typhaceae) were investigated in a mouse model of bronchial asthma. BALB/c mice were immunized and challenged by nasal administration of ovalbumin. Treatment with umbelliferone (60 and 90 mg/kg) caused a marked reduction of cellularity and eosinophil numbers in bronchoalveolar lavage fluids from asthmatic mice. In addition, a decrease in mucus production and lung inflammation were observed in mice treated with umbelliferone. A reduction of IL-4, IL-5, and IL-13, but not of IFN-gamma, was found in bronchoalveolar lavage fluids of mice treated with umbelliferone, similar to that observed with dexamethasone. The levels of ovalbumin-specific IgE were not significantly altered after treatment with umbelliferone. In conclusion, our results demonstrate that umbelliferone attenuates the alteration characteristics of allergic airway inflammation. The investigation of the mechanisms of action of this molecule may contribute for the development of new drugs for the treatment of asthma.
European journal of pharmacology 04/2009; 609(1-3):126-31. · 2.59 Impact Factor
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ABSTRACT: Chagas disease which is caused by the parasite Trypanosoma cruzi is an important cause of cardiomyopathy in Latin America. In later stages chagasic cardiomyopathy is associated with congestive heart failure which is often refractory to medical therapy. In these individuals heart transplantation has been attempted. However, this procedure is fraught with many problems attributable to the surgery and the postsurgical administration of immunosuppressive drugs. Studies in mice suggest that the transplantation of bone-marrow-derived cells ameliorates the inflammation and fibrosis in the heart associated with this infection. Cardiac magnetic resonance imaging reveals that bone marrow transplantation ameliorates the infection induced right ventricular enlargement. On the basis of these animal studies the safety of autologous bone marrow transplantation has been assessed in patients with chagasic end-stage heart disease. The initial results are encouraging and more studies need to be performed.
Interdisciplinary Perspectives on Infectious Diseases 02/2009; 2009:484358.
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ABSTRACT: Research in recent years has demonstrated that the Trypanosoma cruzi cysteine protease cruzain (TCC) is a valid chemotherapeutic target. Herein we describe a small library of aryl-4-oxothiazolylhydrazones that have been tested in assays against T. cruzi cell cultures. The docking studies carried out suggest that these compounds are potential ligands for the TCC enzyme. The most promising compound of this series, N-(4-oxo-5-ethyl-2'-thiazolin-2-yl)-N'-phenylthio-(Z)-ethylidenehydrazone (6 f), was shown to be very active at non-cytotoxic concentrations in in vitro assays with mammalian cells and has a potency comparable with reference drugs such as nifurtimox (Nfx) and benznidazole (Bdz).
ChemMedChem 10/2007; 2(9):1339-45. · 3.15 Impact Factor
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ABSTRACT: Nearly a century after its discovery, Chagas' disease, caused by the protozoan Trypanosoma cruzi, remains a major health problem in Latin America. Although efforts in transmission control have contributed to a decrease in the number of new cases, approximately a third of chronic Chagasic individuals have or will develop the symptomatic forms of the disease, mainly cardiomyopathy. Chagas' disease is a progressively debilitating disease, which, at the final stages, there are no currently available treatments other than heart transplantation. In this scenario, cellular therapy is being tested as an alternative for millions of patients with heart dysfunction due to Chagas' disease. In this article, we review the studies of cellular therapy in animal models and in patients with Chagasic cardiomyopathy and the possible mechanisms by which cellular therapy may act in this disease.
Regenerative Medicine 06/2007; 2(3):257-64. · 3.72 Impact Factor
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ABSTRACT: In experimental Chagas' disease, lymphocytes from mice infected with Trypanosoma cruzi show increased apoptosis in vivo and in vitro. Treatment with a pan-caspase blocker peptide inhibited expression of the active form of effector caspase-3 in vitro and rescued both B and T cells from cell death. Injection of the caspase inhibitor benzyloxycarbonyl-Val-Ala-Asp(OMe)-fluoromethyl ketone, but not a control peptide, reduced parasitemia and lymphocyte apoptosis in T. cruzi-infected mice. Moreover, treatment with caspase inhibitor throughout acute infection increased the absolute numbers of B and T cells in the spleen and lymph nodes, without affecting cell infiltrates in the heart. Following treatment, we found increased accumulation of memory/activated CD4 and CD8 T cells, and secretion of IFN-gamma by splenocytes stimulated with T. cruzi antigens. Caspase inhibition in the course of infection reduced the intracellular load of parasites in peritoneal macrophages, and increased the production of TNF-alpha and nitric oxide upon activation in vitro. Our results indicate that inhibition of caspases with a pan-caspase blocker peptide improves protective type-1 immune responses to T. cruzi infection. We suggest that mechanisms of apoptosis are potential therapeutic targets in Chagas' disease.
European Journal of Immunology 04/2007; 37(3):738-46. · 5.10 Impact Factor
