RESUMEN
Novel strategies for the prevention and treatment of sepsis-associated acute kidney injury and its long-term outcomes have been required and remain a challenge in critical care medicine. Therapeutic strategies using lipid mediators, such as aspirin-triggered resolvin D1 (ATRvD1), can contribute to the resolution of acute and chronic inflammation. In this study, we examined the potential effect of ATRvD1 on long-term kidney dysfunction after severe sepsis. Fifteen days after cecal ligation and puncture (CLP), sepsis-surviving BALB/c mice were subjected to a tubulointerstitial injury through intraperitoneal injections of bovine serum albumin (BSA) for 7 days, called the subclinical acute kidney injury (subAKI) animal model. ATRvD1 treatment was performed right before BSA injections. On day 22 after CLP, the urinary protein/creatinine ratio (UPC), histologic parameters, fibrosis, cellular infiltration, apoptosis, inflammatory markers levels, and mRNA expression were determined. ATRvD1 treatment mitigated tubulointerstitial injury by reducing proteinuria excretion, the UPC ratio, the glomerular cell number, and extracellular matrix deposition. Pro-fibrotic markers, such as transforming growth factor ß (TGFß), type 3 collagen, and metalloproteinase (MMP)-3 and -9 were reduced after ATRvD1 administration. Post-septic mice treated with ATRvD1 were protected from the recruitment of IBA1+ cells. The interleukin-1ß (IL-1ß) levels were increased in the subAKI animal model, being attenuated by ATRvD1. Tumor necrosis factor-α (TNF-α), IL-10, and IL-4 mRNA expression were increased in the kidney of BSA-challenged post-septic mice, and it was also reduced after ATRvD1. These results suggest that ATRvD1 protects the kidney against a second insult such as BSA-induced tubulointerstitial injury and fibrosis by suppressing inflammatory and pro-fibrotic mediators in renal dysfunction after sepsis.
Asunto(s)
Lesión Renal Aguda/tratamiento farmacológico , Aspirina/farmacología , Ácidos Docosahexaenoicos/farmacología , Glomérulos Renales/efectos de los fármacos , Sepsis/tratamiento farmacológico , Lesión Renal Aguda/inducido químicamente , Albúminas/farmacología , Animales , Biomarcadores/metabolismo , Citocinas/metabolismo , Modelos Animales de Enfermedad , Femenino , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Pruebas de Función Renal/métodos , Glomérulos Renales/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Proteinuria/inducido químicamente , Proteinuria/tratamiento farmacológico , Proteinuria/metabolismo , ARN Mensajero/metabolismo , Sepsis/metabolismoRESUMEN
PURPOSE: The aim of this study was to evaluate the expression of the protein annexin A1 (ANXA1), a potent endogenous regulator of the inflammatory process, in ocular toxoplasmosis. METHODS: C57BL/6 female mice were infected using intravitreal injections of either 10(6) tachyzoites of Toxoplasma gondii (RH strain; T. gondii) or PBS only (control groups). After 24, 48, and 72 h, animals were sacrificed and their eyes were harvested for histopathological, immunohistochemical, and ultrastructural immunocytochemical analysis of ANXA1. Human retinal pigment epithelial (RPE) cells (ARPE-19) were infected in vitro with T. gondii and collected after 60, 120, 240 min, and 24 h. RESULTS: Compared with non-infected eyes, an intense inflammatory response was observed in the anterior (24 h after infection) and posterior segments (72 h after infection) of the infected eye, characterized by neutrophil infiltration and by the presence of tachyzoites and their consequent destruction along with disorganization of normal retina architecture and RPE vacuolization. T. gondii infection was associated with a significant increase of ANXA1 expression in the neutrophils at 24, 48, and 72 h, and in the RPE at 48 and 72 h. In vitro studies confirmed an upregulation of ANXA1 levels in RPE cells, after 60 and 120 min of infection with T. gondii. CONCLUSIONS: The positive modulation of endogenous ANXA1 in the inflammatory and RPE cells during T. gondii infection suggests that this protein may serve as a therapeutic target in ocular toxoplasmosis.
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Anexina A1/genética , Segmento Anterior del Ojo/inmunología , Células Epiteliales/inmunología , Segmento Posterior del Ojo/inmunología , Epitelio Pigmentado de la Retina/inmunología , Toxoplasmosis Animal/inmunología , Toxoplasmosis Ocular/veterinaria , Animales , Anexina A1/metabolismo , Segmento Anterior del Ojo/parasitología , Segmento Anterior del Ojo/patología , Células Epiteliales/parasitología , Células Epiteliales/patología , Femenino , Regulación de la Expresión Génica/inmunología , Humanos , Interferón gamma/biosíntesis , Interferón gamma/inmunología , Inyecciones Intravítreas , Ratones , Ratones Endogámicos C57BL , Infiltración Neutrófila/inmunología , Segmento Posterior del Ojo/parasitología , Segmento Posterior del Ojo/patología , Epitelio Pigmentado de la Retina/parasitología , Epitelio Pigmentado de la Retina/patología , Toxoplasma/inmunología , Toxoplasmosis Animal/parasitología , Toxoplasmosis Animal/patología , Toxoplasmosis Ocular/inmunología , Toxoplasmosis Ocular/parasitología , Toxoplasmosis Ocular/patologíaRESUMEN
Leishmania is inoculated, by the bite of an infected sandfly, into the skin of the host, where the promastigotes are phagocyted by dermal macrophages. The dermal region comprises cells and abundant extracellular matrix. Studies show that matrix metalloproteinases play an important role in host defense responses against pathogens in mammals and that their activities lead to the production of antimicrobial peptides. The aim of this study is to evaluate the changes in the distribution of fibronectin and laminin as well as in the elastic system fibres during the course of infection caused by Leishmania amazonensis in mice with distinct genetic backgrounds of susceptibility to this parasite. The results showed that BALB/c presented an enhancement of fibronectin during the course of infection when compared to their control group while the infected or non-infected C3H.He showed a decrease of this protein at end of the experiment. Laminin, on the other hand, remained unaltered in both strains. Also in both BALB/c and C3H.He mice the elastic and elaunin fibres remained unchanged while the oxytalan fibres decreased along the experiment. Ninety days after the infection C3H.He mice had recovered their capacity to produce oxytalan fibres.
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Tejido Elástico/metabolismo , Proteínas de la Matriz Extracelular/metabolismo , Matriz Extracelular/inmunología , Leishmaniasis/inmunología , Animales , Susceptibilidad a Enfermedades , Matriz Extracelular/parasitología , Femenino , Colágenos Fibrilares/metabolismo , Fibronectinas/metabolismo , Laminina/metabolismo , Leishmania/fisiología , Leishmaniasis/parasitología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C3H , Microscopía ConfocalRESUMEN
The present work reports the isolation and biological evaluation of three dimeric xanthones from Paecilomyces sp. EJC01.1 isolated as endophytic from Schnella splendens, a typical plant of the Amazon. The compounds phomoxanthone A (1), phomoxanthone B (2) and dicerandrol B (3) were isolated by chromatographic procedures and identified by spectroscopic methods of 1D and 2D NMR and MS. The extracts and compound 1 showed antimicrobial activities against Bacillus subtilis, Escherichia coli, Staphylococcus aureus, Salmonella typhimurium and Pseudomonas aeruginosa. The compound phomoxanthone A (1) showed greater inhibitory activity against B. subtilis (MIC of 7.81 µg mL-1); in addition, it also pronounced inhibitory effect against promastigote forms of Leishmania amazonensis (IC50 of 16.38 ± 1.079 µg mL-1) and epimastigote forms Trypanosoma cruzi (IC50 of 28.61 ± 1.071 µg mL-1). To provide more information about the antibacterial activity of compound 1, an unprecedented molecular docking study was performed using S-ribosyl-homocysteine lyase (LuxS) (PDB ID 2FQO), which showed a possible interaction of phomoxanthone A with two of the residues (His58 and Cys126) that are fundamental for the catalysis mechanism in B. subtilis, which may be associated with the higher activity, when compared to other bacteria, observed in experimental studies. Additionally, quantum studies (DFT) were performed, for which a low gap value (5.982 eV) was observed, which corroborates the reactivity of phomoxanthone A. Thus, phomoxanthone A can be a good agent against pathogenic bacteria.
RESUMEN
Carajurin is the main constituent of Arrabidaea chica species with reported anti-Leishmania activity. However, its mechanism of action has not been described. This study investigated the mechanisms of action of carajurin against promastigote forms of Leishmania amazonensis. Carajurin was effective against promastigotes with IC50 of 7.96 ± 1.23 µg.mL-1 (26.4 µM), and the cytotoxic concentration for peritoneal macrophages was 258.2 ± 1.20 µg.mL-1 (856.9 µM) after 24 h of treatment. Ultrastructural evaluation highlighted pronounced swelling of the kinetoplast with loss of electron-density in L. amazonensis promastigotes induced by carajurin treatment. It was observed that carajurin leads to a decrease in the mitochondrial membrane potential (p = 0.0286), an increase in reactive oxygen species production (p = 0.0286), and cell death by late apoptosis (p = 0.0095) in parasites. Pretreatment with the antioxidant NAC prevented ROS production and significantly reduced carajurin-induced cell death. The electrochemical and density functional theory (DFT) data contributed to support the molecular mechanism of action of carajurin associated with the ROS generation, for which it is possible to observe a correlation between the LUMO energy and the electroactivity of carajurin in the presence of molecular oxygen. All these results suggest that carajurin targets the mitochondria in L. amazonensis. In addition, when assessed for its drug-likeness, carajurin follows Lipinski''s rule of five, and the Ghose, Veber, Egan, and Muegge criteria.
RESUMEN
Leishmaniasis is a group of neglected tropical diseases whose treatment with antimonials bears limitations and has changed little in over 80 years. Medicinal plants have been evaluated as a therapeutic alternative for leishmaniasis. Arrabidaea chica is popularly used as a wound healing and antiparasitic agent, especially as leishmanicidal agent. This study examined the leishmanicidal activity of a crude extract (ACCE), an anthocyanidin-rich fraction (ACAF), and three isolated anthocyanidins from A. chica: carajurin, 3'-hydroxy-carajurone, and carajurone. We evaluated the antileishmanial activity against promastigote and intracellular amastigote forms of Leishmania amazonensis and determined cytotoxicity in BALB/c peritoneal macrophages, as well as nitrite quantification, using the Griess method. Molecular docking was carried out to evaluate interactions of carajurin at the nitric oxide synthase enzyme. All compounds were active against promastigotes after 72 h, with IC50 values of 101.5 ± 0.06 µg/mL for ACCE and 4.976 ± 1.09 µg/mL for ACAF. Anthocyanidins carajurin, 3'-hydroxy-carajurone, and carajurone had IC50 values of 3.66 ± 1.16, 22.70 ± 1.20, and 28.28 ± 0.07 µg/mL, respectively. The cytotoxicity assay after 72 h showed results ranging from 9.640 to 66.74 µg/mL for anthocyanidins. ACAF and carajurin showed selectivity against intracellular amastigote forms (SI> 10), with low cytotoxicity within 24 h, a statistically significant reduction in all infection parameters, and induced nitrite production. Molecular docking studies were developed to understand a possible mechanism of activation of the nitric oxide synthase enzyme, which leads to an increase in the production of nitric oxide observed in the other experiments reported. These results encourage us to suggest carajurin as a biological marker of A. chica.
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Antocianinas/farmacología , Antiprotozoarios/farmacología , Leishmania mexicana/efectos de los fármacos , Animales , Leishmaniasis Cutánea/tratamiento farmacológico , Macrófagos Peritoneales/efectos de los fármacos , Ratones , Ratones Endogámicos BALB C , Simulación del Acoplamiento Molecular , Óxido Nítrico Sintasa/antagonistas & inhibidores , Extractos Vegetales/farmacología , Hojas de la Planta/química , Plantas MedicinalesRESUMEN
Leishmaniasis encompass a group of infectious parasitic diseases occurring in 97 endemic countries where over one billion people live in areas at risk of infection. It is in the World Health Organization list of neglected diseases and it is considered a serious public health problem, with more than 20,000 deaths a year and high morbidity. Infection by protozoa from the genus Leishmania can cause several forms of the disease, which may vary from a self-healing ulcer to fatal visceral infection. Leishmania species, as well as host immune response and genetics can modulate the course of the disease. Leishmania sp are obligatory intracellular parasites that have macrophages as their main host cell. Depending on the activation phenotype, these cells may have distinct roles in disease development, acting in parasite control or proliferation. Therefore, the purpose of this work was to analyze Leishmania amazonensis infection in primary macrophage cells obtained from mice with two distinct genetic backgrounds, ie. different susceptibility to the infection; evaluating the cause for that difference. After infection, peritoneal macrophages from the resistant C3H/He strain presented lower parasite load when compared to susceptible BALB/c macrophages. The same was also true when cells received a Th2 stimulus after infection, but the difference was abrogated under Th1 stimulus. Nitric oxide production and arginase activity was different between the strains under Th1 or Th2 stimulus, respectively, but iNOS inhibition was unable to suppress C3H/He resistance. Hydrogen peroxide production was also higher in C3H/He than BALB/c under Th1 stimulus, but it could not account for differences in susceptibility. These results led us to conclude that, although they have an important role in parasite control, neither NO nor H2O2 production can explain C3H/He resistance to infection. Other studies are needed to uncover different mechanisms of resistance/susceptibility to L. amazonensis.
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Interacciones Huésped-Patógeno , Leishmania/patogenicidad , Macrófagos/microbiología , Animales , Arginasa/metabolismo , Células Cultivadas , Peróxido de Hidrógeno/metabolismo , Macrófagos/inmunología , Ratones , Ratones Endogámicos BALB C , Óxido Nítrico/metabolismoRESUMEN
Tropical diseases caused by parasitic infections continue to cause socioeconomic distress worldwide. Among these, Chagas disease has become a great concern because of globalization. Caused by Trypanosoma cruzi, there is an increasing need to discover new, more effective methods to manage infections that minimize disease onset. Antimicrobial peptides represent a possible solution to this challenge. As effector molecules of the innate immune response against pathogens, they are the first line of defense found in all multi-cellular organisms. In amphibians, temporins are a large family of antimicrobial peptides found in skin secretions. Their functional roles and modes of action present unique properties that indicate possible candidates for therapeutic applications. Here, we investigated the trypanocide activity of temporizin and temporizin-1. Temporizin is an artificial, hybrid peptide containing the N-terminal region of temporin A, the pore-forming region of gramicidin and a C-terminus consisting of alternating leucine and lysine. Temporizin-1 is a modification of temporizin with a reduction in the region responsible for insertion into membranes. Their activities were evaluated in a cell permeabilization assay by flow cytometry, an LDH release assay, electron microscopy, an MTT assay and patch clamp experiments. Both temporizin and temporizin-1 demonstrated toxicity against T. cruzi with temporizin displaying slightly more potency. At concentrations up to 100 µg/ ml, both peptides exhibited low toxicity in J774 cells, a macrophage lineage cell line, and no toxicity was observed in mouse primary peritoneal macrophages. In contrast, the peptides showed some toxicity in rat adenoma GH3 cells and Jurkat human lymphoma cells with temporizin-1 displaying lower toxicity. In summary, a shortened form of the hybrid temporizin peptide, temporizin-1, was efficient at killing T. cruzi and it has low toxicity in wild-type mammalian cells. These data suggest that temporizin-1 might be a candidate for Chagas disease therapy.
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Enfermedad de Chagas/tratamiento farmacológico , Péptidos/farmacología , Proteínas/farmacología , Trypanosoma cruzi/inmunología , Animales , Péptidos Catiónicos Antimicrobianos , Proliferación Celular , Enfermedad de Chagas/inmunología , Células HEK293 , Humanos , Células Jurkat , L-Lactato Deshidrogenasa/metabolismo , Macrófagos/efectos de los fármacos , Masculino , Ratones , Microscopía ElectrónicaRESUMEN
Chagas disease is a worldwide public health problem. Although the vectorial transmission of Chagas disease has been controlled in Brazil there are other ways of transmission, such as the ingestion of T. cruzi contaminated food, which ensures the continuation of this zoonosis. Here, we demonstrate the influence of the inoculation route on the establishment and development of the SC2005 T. cruzi strain infection in mice. Groups of Swiss mice were infected intragastrically (IG) or intraperitoneally (IP) with the T. cruzi SC2005 strain derived from an outbreak of oral Chagas disease. The results revealed that 100% of IP infected mice showed parasitemia, while just 36% of IG infected showed the presence of the parasite in blood. The parasitemia peaks were later and less intense in the IG infected mice. Mortality of the IP infected animals was more intense and earlier when compared to the IG infected mice. In the IP infected mice leucopenia occurred in the early infection followed by leucocytosis, correlating positively with the increase of the parasites. However, in the IG infected mice only an increase in monocytes was observed, which was positively correlated with the increase of the parasites. Histopathological analyses revealed a myotropic pattern of the SC2005 strain with the presence of inflammatory infiltrates and parasites in different organs of the animals infected by both routes as well as fibrosis foci and collagen redistribution. The flow cytometric analysis demonstrated a fluctuation of the T lymphocyte population in the blood, spleen and mesenteric lymph nodes of the infected animals. T. cruzi DNA associated with the presence of inflammatory infiltrates was detected by PCR in the esophagus, stomach and intestine of all infected mice. These findings are important for the understanding of the pathogenesis of T. cruzi infection by both inoculation routes.
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Enfermedad de Chagas/epidemiología , Enfermedad de Chagas/parasitología , Brotes de Enfermedades , Animales , Brasil/epidemiología , Enfermedad de Chagas/sangre , Enfermedad de Chagas/transmisión , Femenino , Humanos , Recuento de Leucocitos , Ratones , Parasitemia/sangre , Parasitemia/epidemiología , Parasitemia/parasitología , Parasitemia/transmisión , Bazo/parasitología , Timo/parasitologíaRESUMEN
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.
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Arvicolinae/parasitología , Cardiomiopatía Chagásica/tratamiento farmacológico , Ciclofosfamida/uso terapéutico , Modelos Animales de Enfermedad , Inmunosupresores/uso terapéutico , Miocardio/patología , Trypanosoma cruzi/patogenicidad , Animales , Animales no Consanguíneos , Proteínas Portadoras/metabolismo , Proteínas Portadoras/ultraestructura , Cardiomiopatía Chagásica/parasitología , Cardiomiopatía Chagásica/patología , Enfermedad Crónica , Femenino , Humanos , Microscopía Confocal , Microscopía Electrónica , Músculo Esquelético/química , Músculo Esquelético/patología , Miocardio/química , Enfermedades de los Roedores/tratamiento farmacológico , Enfermedades de los Roedores/parasitología , Enfermedades de los Roedores/patologíaRESUMEN
Actinomycin (ActD) is an antibiotic that binds DNA, preventing transcription. When a Trypanosoma cruzi infection in mice is treated with this drug, the parasite loses its ability to multiply, enabling protection. In this study, axenic cultured T. cruzi parasites were exposed to different concentrations of ActD (10, 20, and 50 microg/ml), all of them being able to inhibit growth and to alter the mobility. Nevertheless, the parasites remained alive and motile for at least 14 days. Scanning electron microscopy of trypomastigotes treated with 10 microg/ml of ActD for 24 h showed a modification in their morphology which suggests a change in the parasite cytoskeleton.
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Dactinomicina/farmacología , Trypanosoma cruzi/efectos de los fármacos , Trypanosoma cruzi/ultraestructura , Animales , Antibacterianos/farmacología , Humanos , Locomoción/efectos de los fármacos , Locomoción/fisiología , Microscopía Electrónica de Rastreo , Trypanosoma cruzi/crecimiento & desarrollo , Trypanosoma cruzi/fisiologíaRESUMEN
Objetivo: Avaliar no modelo murino o nível de colonizaçao de cartilagens costais e articulares, assim como os ligamentos pelo Trypanosoma cruzi. Métodos: Estudo histopatológico e histoquímico das cartilagens, ligamentos e musculatura esquelética em camundongos atímicos e eutímicos na fase aguda da doença de Chagas experimental. Resultados: Foi observado que em camundongos jovens, infectados com duas amostras polares de T. cruzi, as cartilagens, os ligamentos, a musculatura esquelética e a medula óssea apresentavam-se altamente colonizados pelo parasito. A colonizaçao do pericôndrio e ligamentos muitas vezes está associada com uma reaçao inflamatória em que predomina um infiltrado mononuclear. A idade é um fator importante na colonizaçao da cartilagem pelo parasito, sendo rara em camundongos adultos. A miosite observada no miocárdio e músculos esqueléticos de camundongos, que apresentam a resposta T-dependente intacta, muitas vezes mostra uma paralisia de membros posteriores. Neste caso, observamos certa freqüência de calcificaçao da fibra muscular demonstrada por testes histoquímicos. Camundongos atímicos (Nude) nao têm miosite nem calcificaçao, porém apresentam carga parasitária em níveis extraordinários na musculatura lisa e estriada. Conclusoes: Os fenômenos de paralisia na fase aguda aparecem com freqüência associados com calcificaçoes observadas na musculatura esquelética e a uma intensa miosite. Os resultados mostraram que estes aspectos da patologia da doença de Chagas experimental estao relacionados com a resposta T-dependente, pois camundongos atímicos nunca apresentaram o quadro acima descrito, apesar da intensa carga parasitária nos tecidos musculares. Cepas polares, quer sejam miotrópica ou reticulotrópicas, estao envolvidas com os fenômenos de paralisia. Os condrócitos sao colonizados pelo T. cruzi, assim como o pericôndrio, o que desencadeia um processo inflamatório local
Asunto(s)
Animales , Ratones , Cartílago , Miositis , Trypanosoma cruziRESUMEN
A indometacina administrada por via oral ou intraperitoneal, na dose de 5mg/kg diariamente, durante infecçäo experimental em camundongos por Trypanosoma cruzi, provocou o aparecimento de reaçöes adversas similares àquelas observadas através do emprego de outros antiinflamatórios, tais como os corticosteróides. A parasitemia observada nos camundongos pertencentes ao grupo dos tratados pela indometacina foi significativamente mais elevada que nos grupos-controle. A taxa de mortalidade correlacionou-se aos níveis de parasitemia. Foram observados em quase todos os tecidos dos camundongos pertencentes ao grupo dos tratados com indometacina e infectados pelo T. cruzi cepa Y, do que nos grupos-controle normais. Näo foi observada infiltraçäo celular em camundongos tratados pela indometacina (tecidos infectados) enquanto um infiltrado duro de células mononucleares foi observado nos grupos-controle. As implicaçöes clínicas em pacientes chagásicos säo discutidas