RESUMO
This study describes changes in oxidative stress (OS) parameters in mice experimentally infected with Angiostrongylus costaricensis, which causes abdominal angiostrongyliasis. For this, 28 Swiss mice were used, divided into two groups (G1 and G2), with 14 animals each. Of these, eight were infected with ten infective larvae each, by gavage, and six were used as a control group. Mice from G1 and G2 were euthanized at 14 days and 24 days post-infection, respectively. Tissue samples were used for histopathological analysis and blood (serum) samples were taken to assess the levels of proteins, non-protein thiols (NPTs) and nitric oxide (NO), from centrifugation and subsequent collection of aliquots of the supernatant. Among OS parameters, infected mice in both groups had higher NO levels than the control group, due to the presence of: eosinophil infiltrate in the liver and intestine; pancreatitis; and intestinal granuloma. However, the infected mice of both groups showed a reduction in the levels of NPTs, in relation to the control group, due to the presence of: eosinophilic infiltrate in the liver and intestine; and intestinal granuloma. Our results suggest that A. costaricensis infection has important effects on the intestine, liver and pancreas, and the analyses were performed from the tissue of these organs. The mechanisms for these changes are related to the decrease in the body's main antioxidant defences, as demonstrated by the reduction of NPTs, thus contributing to the development of more severe tissue damage. Thus, the objective of the present study was to evaluate the relationship between histopathological lesions and markers for OS.
Assuntos
Angiostrongylus , Infecções por Strongylida , Camundongos , Animais , Granuloma , Estresse OxidativoRESUMO
This study describes changes in haematological parameters, cytokine profile, histopathology and cortisol levels in Swiss mice experimentally infected with Angiostrongylus costaricensis. Twenty-eight Swiss mice were divided into two groups (G1 and G2) of 14 animals each. In each group, eight animals were infected orally with ten third-stage larvae of A. costaricensis and six were used as a control group. The mice of groups G1 and G2 were sacrificed 14 and 24 days after infection, respectively. Samples were collected for histopathological and haematological analyses and determination of the cytokine profile and cortisol levels. Granulomatous reaction, eosinophilic infiltrate and vasculitis in the intestinal tract, pancreas, liver and spleen were observed with varying intensity in infected animals. Our results showed that the mice developed normocytic and hypochromic anaemia, and that the histopathological lesions caused by the experimental infection influenced increases in cortisol, neutrophil and monocyte levels. In addition to this, we detected increased interleukin-6 and tumour necrosis factor alpha levels in the infected animals.
Assuntos
Angiostrongylus , Infecções por Strongylida , Animais , Hidrocortisona , Intestinos , Larva , CamundongosRESUMO
Abdominal angiostrongyliasis is caused by Angiostrongylus costaricensis, the definitive and intermediate hosts of which are wild rodents and terrestrial molluscs, respectively. Humans are accidental hosts and can be infected by ingesting the third-stage (infective) larvae (L3). It remains unclear whether the number of L3 inoculated is related to lesion severity. Our aim was to analyse histopathological alterations in Swiss mice infected with different doses of A. costaricensis. Thirty-two mice were randomly divided into four groups (n = 8/group): uninfected, control mice; mice infected with a low dose (five L3); mice infected with an intermediate dose (15 L3); and mice infected with a high dose (30 L3). The frequency of intestinal thrombi, splenitis, eggs/larvae, hepatic infarction and acute pancreatitis differed among the groups, the last being considered a significant finding. We conclude that different infective doses alter the histopathological aspects of the infection in Swiss mice, those aspects being more pronounced at medium and high doses, with no effect on the development of the disease. This experimental model shows that the parasite life cycle can be maintained in Swiss mice through the inoculation of a low dose (five L3).
Assuntos
Trato Gastrointestinal/patologia , Trato Gastrointestinal/parasitologia , Interações Hospedeiro-Parasita , Carga Parasitária , Infecções por Strongylida/parasitologia , Doença Aguda , Angiostrongylus/patogenicidade , Animais , Larva/patogenicidade , Masculino , Camundongos , Pancreatite/parasitologiaRESUMO
Abdominal angiostrongyliasis is an endemic zoonosis in southern Brazil caused by the nematode Angiostrongylus costaricensis, which uses terrestrial molluscs as intermediate hosts and wild rodents as final hosts. Humans can be infected by ingesting infectious A. costaricensis larvae. To date, correlations between shedding of first-stage larvae (L1) and different infective doses of third-stage larvae (L3) have not been elucidated. The aim of this study was to assess L1 faecal shedding levels in Swiss mice experimentally infected with different doses of A. costaricensis L3 and to determine whether infective doses are related to mortality. Thirty-two male Swiss mice were divided evenly into a non-infected control (NI-Con); low-dose infection (LD-Inf); medium-dose infection (MD-Inf) and high-dose infection (HD-Inf) groups infected with 0, 5, 15 and 30 A. costaricensis L3, respectively. Faecal samples were collected from each animal, starting at day 20 post infection. HD-Inf mice had greater faecal L1 shedding levels than LD-Inf mice, but not a significantly shortened survival. In conclusion, infective doses of A. costaricensis L3 affect L1 shedding levels without altering mortality in Swiss mice.
Assuntos
Angiostrongylus/fisiologia , Fezes/parasitologia , Infecções por Strongylida/parasitologia , Angiostrongylus/genética , Animais , Modelos Animais de Doenças , Humanos , Larva/genética , Larva/fisiologia , Masculino , CamundongosRESUMO
This study aimed to evaluate in vitro and in vivo trypanocidal activity of free and nanoencapsulated curcumin against Trypanosoma evansi. In vitro efficacy of free curcumin (CURC) and curcumin-loaded in lipid-core nanocapsules (C-LNCs) was evaluated to verify their lethal effect on T. evansi. To perform the in vivo tests, T. evansi-infected animals were treated with CURC (10 and 100 mg kg(-1), intraperitoneally [i.p.]) and C-LNCs (10 mg kg(-1), i.p.) during 6 days, with the results showing that these treatments significantly attenuated the parasitaemia. Infected untreated rats showed protein peroxidation and an increase of nitrites/nitrates, whereas animals treated with curcumin showed a reduction on these variables. As a result, the activity of antioxidant enzymes (superoxide dismutase and catalase) differs between groups (P<0.05). Infected animals and treated with CURC exhibited a reduction in the levels of alanine aminotransferase and creatinine, when compared with the positive control group. The use of curcumin in vitro resulted in a better parasitaemia control, an antioxidant activity and a protective effect on liver and kidney functions of T. evansi-infected adult male Wistar rats.
Assuntos
Curcumina/farmacologia , Tripanossomicidas/farmacologia , Trypanosoma/efeitos dos fármacos , Tripanossomíase/tratamento farmacológico , Produtos da Oxidação Avançada de Proteínas/sangue , Alanina Transaminase/metabolismo , Fosfatase Alcalina/metabolismo , Animais , Aspartato Aminotransferases/metabolismo , Catalase/sangue , Creatinina/metabolismo , Curcumina/administração & dosagem , Cães , Concentração de Íons de Hidrogênio , Rim/parasitologia , Rim/patologia , Rim/fisiopatologia , Fígado/enzimologia , Fígado/parasitologia , Fígado/patologia , Masculino , Nanocápsulas , Nitratos/sangue , Nitritos/sangue , Parasitemia/tratamento farmacológico , Parasitemia/parasitologia , Ratos , Ratos Wistar , Superóxido Dismutase/sangue , Tripanossomicidas/administração & dosagem , Tripanossomíase/patologiaRESUMO
De 2.212 pacientes submetidos à cirurgia cardíaca sob circulação extracorpórea (CEC), 32 (1,4%) desenvolveram insuficiência renal aguda (IRA) no pós-operatório imediato. os dados obtidos nesses casos (grupo I) foram comparados aos de 458 pacientes operados e que não apresentaram IRA (grupo II). Os valores médios da idade, do tempo de CEC e de clampeamento aórtico, assim como a incidência de hipotensão arterial sistêmica e de hemoglobinúria pós-operatórias foram significativamente maiores no grupo I. Esses parãmetros não foram significativamente diferentes nos pacientes com perda mais acentuada da função renal, mas foram maiores nos 15 pacientes que morreram (48,4%) em relação aos 17 que sobreviveram (51,6%), embora sem significância estatística. dos 21 pacientes tratados conservadoramente no grupo I, 9 morreram (42,9%), tendo ocorrido 6 óbitos (54,5%) nos outros 11 casos tratados com diálise (não significativo). Concluímos que a faixa etária, o tempo de CEC e de clampeamento aórtico, a hipotensão arterial sistêmica e a hemoglobinúria são fatores importantes no desencadeamento de IRA em cirurgia cardíaca. A incidência dessa entidade é baixa em nossa instituição e sua mortalidade tende a ser maior nos pacientes submetidos à diálise, fato que poderia estar relacionado à maior gravidade clínica desses casos.
Of 2,212 patients undergoing cardiac surgery under cardiopulmonary bypass (CPB), 32 (1.4%) developed acute renal failure (ARF) in the immediate postoperative period. data obtained in these cases (group I) were compared with 458 patients operated and not ARF (group II). The mean values of age, CPB time and aortic clamping, as well as the incidence of hypotension and postoperative hemoglobinuria were significantly higher in group I. These parameters were not significantly different in patients with more severe loss of kidney function, but were higher in 15 patients who died (48.4%) compared with 17 who survived (51.6%), although not statistically significant. 21 patients were treated conservatively in group I, 9 died (42.9%), with 6 deaths occurred (54.5%) in the other 11 cases treated with dialysis (not significant). We conclude that age, CPB time and aortic clamping, systemic arterial hypotension and hemoglobinuria are important factors in the onset of ARF in cardiac surgery. The incidence of this entity is low in our institution and its mortality rate tends to be higher in dialysis patients, which could be related to the clinical severity of these cases.