Cruzipain, a major Trypanosoma cruzi antigen, promotes arginase-2 expression and survival of neonatal mouse cardiomyocytes

Faculty of Chemical Science, National University of Cordoba, Argentina, Córdoba, Cordoba, Argentina
AJP Cell Physiology (Impact Factor: 3.78). 03/2004; 286(2):C206-12. DOI: 10.1152/ajpcell.00282.2003
Source: PubMed


An intense myocarditis is frequently found in the acute phase of Trypanosoma cruzi infection. Despite the cardiac damage, infected individuals may remain asymptomatic for decades. Thus T. cruzi may directly prevent cardiomyocyte death to keep heart destruction in check. Recently, it has been shown that Schwann cell invasion by T. cruzi, their prime target in the peripheral nervous system, suppressed host cell apoptosis caused by growth factor deprivation. Likewise, the trans-sialidase of T. cruzi reproduced this antiapoptotic activity of the parasite. In this study, we have investigated the effect of cruzipain, another important T. cruzi antigen, on survival and cell death of neonatal BALB/c mouse cardiomyocyte cultures. We have found that cruzipain, as well as T. cruzi infection, promoted survival of cardiomyocytes cultured under serum deprivation. The antiapoptotic effect was mediated by Bcl-2 expression but not by Bcl-xL expression. Because arginase activity is involved in cell differentiation and wound healing in most cell types and it favors parasite growth within the cell, we have further investigated the effect of cruzipain on the regulation of l-arginine metabolic pathways. Our results have revealed that cruzipain enhanced arginase activity and the expression of arginase-2 isoform but failed to induce nitric oxide synthase activity. In addition, the inhibition of arginase activity by NG-hydroxy-l-arginine, abrogated the antiapoptotic action of cruzipain. The results demonstrate that cruzipain may act as a survival factor for cardiomyocytes because it rescued them from apoptosis and stimulated arginase-2.

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Available from: Maria Del Pilar Aoki, Mar 18, 2014
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    • "Over the last decade, research to clarify cardiomyocyte behaviour after parasitic infection has been conducted (Petersen & Burleigh 2003, Calvet et al. 2012, Corral et al. 2013). Some studies reported the activation of the phosphatidylinositol-3 kinase (PI3K)/Akt pathway in T. cruzi infected cells (Chuenkova et al. 2001, Aoki et al. 2004) and this activation contributes to host cell survival or death. PI3K controls important steps in cellular metabolism by regulating the production of the second messenger phosphatidylinositol-3,4,5-trisphos- phate (PIP3), which is able to activate AKT and downstream signalling events such as heart hypertrophy, cellular proliferation, and even apoptosis (Maehama & Dixon 1998). "
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    ABSTRACT: Chagas disease, which is caused by the intracellular protozoan Trypanosoma cruzi, is a serious health problem in Latin America. The heart is one of the major organs affected by this parasitic infection. The pathogenesis of tissue remodelling, particularly regarding cardiomyocyte behaviour after parasite infection, and the molecular mechanisms that occur immediately following parasite entry into host cells are not yet completely understood. Previous studies have reported that the establishment of parasitism is connected to the activation of the phosphatidylinositol-3 kinase (PI3K), which controls important steps in cellular metabolism by regulating the production of the second messenger phosphatidylinositol-3,4,5-trisphosphate. Particularly, the tumour suppressor PTEN is a negative regulator of PI3K signalling. However, mechanistic details of the modulatory activity of PTEN on Chagas disease have not been elucidated. To address this question, H9c2 cells were infected with T. cruzi Berenice 62 strain and the expression of a specific set of microRNAs (miRNAs) were investigated. Our cellular model demonstrated that miRNA-190b is correlated to the decrease of cellular viability rates by negatively modulating PTEN protein expression in T. cruzi-infected cells.
    Full-text · Article · Dec 2015 · Memórias do Instituto Oswaldo Cruz
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    • "In addition, engagement of gp130 also leads to the activation of Ras-ERK1/2/MAPK and PI3K/ AKT pathways [7]. We have previously demonstrated that the parasite cysteine protease , cruzipain, when devoid of enzymatic activity, improves the pro-survival effect elicited by the parasite in cardiomyocyte cultures [8]. Related to this, cruzipain itself induces cardiomyocyte survival through the activation of two signal transduction pathways, the PI3K/Akt and MEK1/ERK, with both pathways leading to a decrease in the activated caspase-3 [9]. "
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    ABSTRACT: Interleukin-6 mediates host defense and cell survival mainly through the activation of the transcription factor STAT3 via the glycoprotein gp130, a shared signal-transducing receptor for several IL-6-type cytokines. We have reported that the cardiotrophic parasite Trypanosoma cruzi protects murine cardiomyocytes from apoptosis. In agreement, an intense induction of the anti-apoptotic factor Bcl-2 is found in cardiac fibers during the acute phase of infection, establishing a higher threshold against apoptosis. We report here that inactive cruzipain, the main cysteine protease secreted by the parasite, specifically triggered TLR2 and the subsequent release of IL-6, which acted as an essential anti-apoptotic factor for cardiomyocyte cultures. Although comparable IL-6 levels were found under active cruzipain stimulation, starved cardiac cell monolayers could not be rescued from apoptosis. Moreover, cardiomyocytes treated with active cruzipain completely abrogated the STAT3 phosphorylation and nuclear translocation induced by recombinant IL-6. This inhibition was also observed on splenocytes, but it was reverted when the enzyme was complexed with chagasin, a parasite cysteine protease inhibitor. Furthermore, the inhibition of IL-6-induced p-STAT3 was evidenced in spleen cells stimulated with pre-activated supernatants derived from trypomastigotes. To account for these observations, we found that cruzipain enzymatically cleaved recombinant gp130 ectodomain, and induced the release of membrane-distal N-terminal domain of this receptor on human peripheral blood mononuclear cells. These results demonstrate, for the first time, that the parasite may modify the IL-6-induced response through the modulation of its cysteine protease activity, suggesting that specific inhibitors may help to improve the immune cell activation and cardioprotective effects.
    Full-text · Article · Dec 2012 · Biochimica et Biophysica Acta
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    • "The resulting increase in arginase A1 activity leads to the consumption of L-arginine and to a decrease in NO synthesis that favors the proliferation of Leishmania in macrophages (Wanderley and Barcinski, 2010). T. cruzi, which lacks arginase, establishes a host–parasite relationship by producing cruzipain, which induces the synthesis of arginase A2 in host cardiomyocytes (Aoki et al., 2004) or arginase A1 in macrophages (Cuervo et al., 2008). Thus, the parasite drives the production of putrescine in infected cells and ingests putrescine for its own polyamine biosynthesis (Heby et al., 2007). "
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    ABSTRACT: Polyamine biosynthesis enzymes are promising drug targets for the treatment of leishmaniasis, Chagas' disease and African sleeping sickness. Arginase, which is a metallohydrolase, is the first enzyme involved in polyamine biosynthesis and converts arginine into ornithine and urea. Ornithine is used in the polyamine pathway that is essential for cell proliferation and ROS detoxification by trypanothione. The flavonols quercetin and quercitrin have been described as antitrypanosomal and antileishmanial compounds, and their ability to inhibit arginase was tested in this work. We characterized the inhibition of recombinant arginase from Leishmania (Leishmania) amazonensis by quercetin, quercitrin and isoquercitrin. The IC(50) values for quercetin, quercitrin and isoquercitrin were estimated to be 3.8, 10 and 4.3 μM, respectively. Quercetin is a mixed inhibitor, whereas quercitrin and isoquercitrin are uncompetitive inhibitors of L. (L.) amazonensis arginase. Quercetin interacts with the substrate l-arginine and the cofactor Mn(2+) at pH 9.6, whereas quercitrin and isoquercitrin do not interact with the enzyme's cofactor or substrate. Docking analysis of these flavonols suggests that the cathecol group of the three compounds interact with Asp129, which is involved in metal bridge formation for the cofactors Mn(A)(2+) and Mn(B)(2+) in the active site of arginase. These results help to elucidate the mechanism of action of leishmanicidal flavonols and offer new perspectives for drug design against Leishmania infection based on interactions between arginase and flavones.
    Full-text · Article · Mar 2012 · Experimental Parasitology
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