RESUMO
The aim of this study was to evaluate the cholinesterase activity in serum, whole blood, and lymphocytes, as well as to verify its relation to immune response in rats experimentally infected by Sporothrix schenckii. For this study, 63 Wistar rats (Rattus norvegicus), male, adult were divided into three groups: the negative control group (GC: n = 21), the group infected subcutaneously (GSC: n = 21), and the group infected intraperitoneally (GIP: n = 21). The groups were divided into subgroups and the following variables were evaluated at 15, 30, and 40 days post-infection (PI): acetylcholinesterase (AChE) activity in lymphocytes and whole blood, butyrylcholinesterase (BChE) activity in serum, cytokines levels (IL-1, IL-6, TNFα, and INF-γ), immunoglobulins levels (IgA, IgG, IgM, and IgE), and protein profile by electrophoresis. Both infected groups showed increased levels of inflammatory parameters (P < 0.05) in tissue and inflammatory infiltrates. The activities of AChE in lymphocytes and BChE in serum increased (P < 0.05) significantly in animals from the GSC group on day 40 PI compared to the GC group. Regarding the GIP, there was a marked increase in the AChE activity in lymphocytes on days 30 and 40 PI, and in whole blood on days 15, 30, and 40 PI compared to GC. Furthermore, IL-10, an anti-inflammatory cytokine, was also present in high levels during chronic systemic S. schenckii infections in animals. Therefore, it is concluded that cholinesterase has an important modulatory role in the immune response during granulomatous infection by S. schenckii.
Assuntos
Colinesterases/análise , Inflamação/patologia , Sporothrix/crescimento & desenvolvimento , Esporotricose/patologia , Animais , Anticorpos Antifúngicos/sangue , Citocinas/análise , Modelos Animais de Doenças , Linfócitos/enzimologia , Masculino , Proteínas/análise , Ratos Wistar , Soro/enzimologiaRESUMO
OBJECTIVE: To evaluate the possible renal and hepatic toxicity of tepoxalin in dogs exposed to hypotension during isoflurane anesthesia. STUDY DESIGN: Prospective, randomized experimental study. ANIMALS: Twenty adult mixed-breed dogs, weighing 18.8 ± 2.8 kg. METHODS: The animals received 10 mg kg(-1) tepoxalin orally 2 hours before the anesthetic procedure (PRE; n = 6), or 30 minutes after anesthesia (POST; n = 6), along with a control group (CON; n = 8), which were only anesthetized. The PRE and POST groups also received the same dose of tepoxalin for 5 days post-procedure. All dogs were anesthetized with propofol and maintained with isoflurane and the end-tidal isoflurane (Fe'Iso) was increased until mean arterial pressure decreased to 50-60 mmHg. These pressures were maintained for 60 minutes. Heart rate, arterial pressures and Fe'Iso were recorded at 0, 10 and every 10 minutes up to 60 minutes of hypotension. Blood gases, pH, electrolytes and bleeding time were analyzed before and at 30 and 60 minutes of hypotension. Renal and hepatic changes were quantified by serum and urinary biochemistry and creatinine clearance. RESULTS: Serum concentrations of alanine amino transferase (ALT), alkaline phosphatase (ALP) and γ-glutamyl transferase (GGT), blood urea nitrogen (BUN) and creatinine (Cr), and urinary output, urinary Cr, Cr clearance, and GGT:Cr ratio remained stable throughout the evaluations. During the anesthetic procedure there were no important variations in the physiological parameters. No side effects were observed in any of the groups. CONCLUSIONS AND CLINICAL RELEVANCE: Tepoxalin did not cause significant effects on renal function or cause hepatic injury in healthy dogs exposed to hypotension with isoflurane, when administered pre- or postanesthetic and continued for five consecutive days.
Assuntos
Anestesia por Inalação/veterinária , Anti-Inflamatórios não Esteroides/administração & dosagem , Cães/fisiologia , Rim/efeitos dos fármacos , Pirazóis/administração & dosagem , Anestésicos Inalatórios/administração & dosagem , Animais , Feminino , Taxa de Filtração Glomerular/efeitos dos fármacos , Taxa de Filtração Glomerular/veterinária , Isoflurano/administração & dosagem , Fígado/efeitos dos fármacos , Masculino , Estudos Prospectivos , Resultado do TratamentoRESUMO
The aim of this study was to investigate neurochemical and enzymatic changes in rats infected with Trypanosoma evansi, and their interference in the cognitive parameters. Behavioural assessment (assessment of cognitive performance), evaluation of cerebral L-[3H]glutamate uptake, acetylcholinesterase (AChE) activity and Ca+2 and Na+, K+-ATPase activity were evaluated at 5 and 30 days post infection (dpi). This study demonstrates a cognitive impairment in rats infected with T. evansi. At 5 dpi memory deficit was demonstrated by an inhibitory avoidance test. With the chronicity of the disease (30 dpi) animals showed anxiety symptoms. It is possible the inhibition of cerebral Na+, K+-ATPase activity, AChE and synaptosomal glutamate uptake are involved in cognitive impairment in infected rats by T. evansi. The understanding of cerebral hostparasite relationship may shed some light on the cryptic symptoms of animals and possibly human infection where patients often present with other central nervous system (CNS) disorders.
Assuntos
Ansiedade/parasitologia , Interações Hospedeiro-Parasita , Trypanosoma/fisiologia , Tripanossomíase/fisiopatologia , Acetilcolinesterase/metabolismo , Animais , Ataxia , Comportamento Animal , ATPases Transportadoras de Cálcio/metabolismo , Transtornos Cognitivos , Cães , Ácido Glutâmico/análise , Humanos , Masculino , Aprendizagem em Labirinto , Sistema Nervoso/química , Parasitemia , Ratos , Ratos Wistar , ATPase Trocadora de Sódio-Potássio/metabolismo , Trítio/análise , Tripanossomíase/parasitologiaRESUMO
BACKGROUND: Rangelia vitalii is a tick-transmitted piroplasm that causes both hemolytic and hemorrhagic disease in dogs in Brazil. OBJECTIVE: The aim of this study was to evaluate the response of the bone marrow in dogs experimentally infected with R vitalii during the acute stage of the disease. METHODS: For this study, 2 groups of a total of 12 young dogs were used. Group A was composed of healthy dogs (n = 5), and group B consisted of animals infected with R vitalii (n = 7). Blood samples were collected on days 0, 10, 20, and 30 post-inoculation and stored in EDTA tubes for a full hematology profile, including a reticulocyte count. On days 10 and 20, bone marrow samples were collected, stained, and examined. RESULTS: In infected dogs anemia was identified on days 10 and 20 post-inoculation (P < .01), and on day 20 reticulocytosis was present. Infected dogs had leukopenia due to neutropenia and eosinopenia, along with lymphocytosis and monocytosis, when compared with control animals. In bone marrow, the myeloid:erythroid ratio was significantly decreased (P < .05) in infected dogs due to increased erythroid precursors. CONCLUSIONS: Dogs experimentally infected with R vitalii develop regenerative extravascular hemolytic anemia accompanied by erythroid hyperplasia in the bone marrow. During the acute phase of the disease, leukopenia due to neutropenia and eosinopenia suggests intense tissue recruitment of these cells in response to the endothelial damage caused by this parasite.
Assuntos
Anemia Hemolítica/veterinária , Babesia/classificação , Babesiose/veterinária , Medula Óssea/patologia , Doenças do Cão/parasitologia , Anemia Hemolítica/parasitologia , Animais , Antiprotozoários/uso terapêutico , Babesiose/sangue , Babesiose/tratamento farmacológico , Babesiose/parasitologia , Babesiose/patologia , Diminazena/análogos & derivados , Diminazena/uso terapêutico , Doenças do Cão/sangue , Doenças do Cão/tratamento farmacológico , Doenças do Cão/patologia , Cães , Células Eritroides/patologia , Feminino , Hiperplasia/veterináriaRESUMO
This study aimed to measure the levels of interferon-gamma (IFN-γ), tumor necrosis factor-alpha (TNF-α), interleukin 1 (IL-1), interleukin 6 (IL-6), and nitrite/nitrate (NO x ) in serum of dogs experimentally infected with Rangelia vitalii. Twelve female mongrel dogs were divided into 2 groups; group A (uninfected controls) composed by healthy dogs (n=5) and group B consisting of dogs inoculated with R. vitalii (n=7). Animals were monitored by blood smear examinations, which showed intraerythrocytic forms of the parasite on day 5 post-infection (PI). Blood samples were collected through the jugular vein on days 0, 10, and 20 PI to determine the serum levels of IFN-γ, TNF-α, IL-1, IL-6, and NO x . Cytokines were assessed by ELISA quantitative sandwich technique, and NO x was measured by the modified Griess method. Cytokine levels (IFN-γ, TNF-α, IL-1, and IL-6) were increased (P<0.01) in serum of infected animals. Serum levels of NO x were also increased on days 10 PI (P<0.01) and 20 PI (P<0.05) in infected animals. Therefore, the infection with R. vitalii causes an increase in proinflammatory cytokines and nitric oxide content. These alterations may be associated with host immune protection against the parasite.
Assuntos
Citocinas/sangue , Óxido Nítrico/sangue , Piroplasmida/imunologia , Infecções por Protozoários/imunologia , Animais , Técnicas de Química Analítica , Modelos Animais de Doenças , Cães , Ensaio de Imunoadsorção Enzimática , Feminino , Infecções por Protozoários/parasitologia , Infecções por Protozoários/patologia , Soro/químicaRESUMO
The present study aimed to evaluate the serum proteinogram, acute phase proteins (APPs) and immunoglobulins (Igs) of dogs experimentally infected by Rangelia vitalii in the acute phases of the disease. Banked serum samples collected on days 0, 10 and 20 during a previously reported R. vitalii experimental infection were used to analyze the serum proteinogram, APPs (C-reactive protein - CRP and alpha-1-acid glycoprotein - AGP) and Igs (IgM, IgG, IgA and IgE) in the current study. Total protein and albumin level were significantly (P<0.05) decreased at day 10 PI and 20 PI in infected sera compared to the control sera. Alpha-1 globulin (day 10 PI) and gamma globulin (day 20 PI) were increased (P<0.01) in infected sera. Alpha-2 globulin (days 10 and 20 PI) and beta-2 globulin (day 10 PI) were decreased (P<0.05) in infected sera compared to control sera. Beta-1 globulin fraction did not differ statistically between sera. Serum CRP and AGP concentrations were significantly increased (P<0.05) at days 10 and 20 PI in infected sera. IgG was increased at days 10 (P<0.05) and 20 PI (P<0.01) in infected sera. Furthermore, it was also observed an increase (P<0.01) in the levels of IgM, IgA, and IgE in infected sera than control sera. We conclude that R. vitalii infection causes alterations in the proteinogram, and increases in the levels of APPs and Igs. Further studies are essentials to define the causes of these pathological changes in this disease.
Assuntos
Proteínas de Fase Aguda/metabolismo , Proteínas Sanguíneas/metabolismo , Doenças do Cão/metabolismo , Imunoglobulinas/metabolismo , Piroplasmida/fisiologia , Infecções Protozoárias em Animais/metabolismo , Animais , Doenças do Cão/imunologia , Doenças do Cão/parasitologia , Cães , Infecções Protozoárias em Animais/imunologia , Infecções Protozoárias em Animais/parasitologiaRESUMO
The potent activity against Trypanosomes and health beneficial effects of curcumin (Cur) has been demonstrated in various experimental models. In this study, we evaluated the in vivo effect of Cur as trypanocide and as potential anti-inflammatory agent, through the evaluation of immunomodulatory mechanisms in rats infected with Trypanosoma evansi. Daily oral Cur was administered at doses of 0, 20 or 60mg/kg as preventive treatment (30 and 15days pre infection) and as treatment (post infection). The treatment of the groups continued until the day of euthanasia. Fifteen days after inoculation, parasitemia, plasma proinflammatory cytokines (IFN-γ, TNF-α, IL-1, IL-6), anti-inflammatory cytokines (IL-10) and blood acetylcholinesterase activity (AChE) were analyzed. Pretreatment with Cur reduced parasitemia and lethality. Cur inhibited AChE activity and improved immunological response by cytokines proinflammatory, fundamental during T. evansi infection. We found that Cur is not so important as an antitrypanosomal activity but as immunomodulator agent. These findings reveal that the preventive use of Cur stimulates anti-inflammatory mechanisms, reducing an excessive inflammatory response.
Assuntos
Acetilcolinesterase/sangue , Anti-Inflamatórios não Esteroides/farmacologia , Curcumina/farmacologia , Citocinas/sangue , Fatores Imunológicos/farmacologia , Tripanossomíase/imunologia , Acetilcolinesterase/metabolismo , Administração Oral , Animais , Anti-Inflamatórios não Esteroides/uso terapêutico , Inibidores da Colinesterase/farmacologia , Inibidores da Colinesterase/uso terapêutico , Curcumina/administração & dosagem , Curcumina/uso terapêutico , Citocinas/metabolismo , Modelos Animais de Doenças , Fatores Imunológicos/uso terapêutico , Masculino , Parasitemia , Distribuição Aleatória , Ratos , Ratos Wistar , Trypanosoma/efeitos dos fármacos , Trypanosoma/imunologia , Tripanossomíase/tratamento farmacológico , Tripanossomíase/enzimologia , Tripanossomíase/prevenção & controleRESUMO
Several chemical and immunohistochemical techniques can be used for the detection of acetylcholinesterase (AChE) activity. In this experiment we aimed to detect AChE activity in Trypanosoma evansi. For this, the parasites were isolated from the blood of experimentally infected rats using a DEA-cellulose column. Enzymatic activity was determined in trypomastigote forms at 0, 0.2, 0.4, 0.8 and 1.2 mg/mL of protein concentrations by a standard biochemical protocol. At all concentrations tested, the study showed that T. evansi expresses the enzyme AChE and its activity was proportional to the concentration of protein, ranging between 0.64 and 2.70 µmol of AcSCh/h. Therefore, we concluded that it is possible to biochemically detect AChE in T. evansi, an enzyme that may be associated with vital functions of the parasite and also can be related to chemotherapy treatments, as further discussed in this article.
Assuntos
Acetilcolinesterase/análise , Trypanosoma/enzimologia , Acetilcolina/metabolismo , Acetilcolinesterase/fisiologia , Animais , Bioquímica/métodos , Cromatografia DEAE-Celulose , Humanos , Linfócitos/enzimologia , Linfócitos/parasitologia , Parasitemia/parasitologia , Ratos , Espectrofotometria , Tripanossomíase/parasitologiaRESUMO
The aim of this study is to evaluate the role of cholinesterases as an inflammatory marker in acute and chronic infection by Trypanosoma evansi in rabbits experimentally infected. Twelve adult female New Zealand rabbits were used and divided into two groups with 6 animals each: control group (rabbits 1-6) and infected group (rabbits 7-12). Infected group received intraperitoneally 0.5 mL of blood from a rat containing 108 parasites per animal. Blood samples used for cholinesterases evaluation were collected on days 0, 2, 7, 12, 27, 42, 57, 87, 102 and 118 days post-inoculation (PI). Increased activity (P<0.05) of butyrylcholinesterase (BChE) and acetylcholinesterase (AChE) were observed in the blood on days 7 and 27, respectively and no differences were observed in cholinesterase activity in other periods. No significant difference in AChE activity (P>0.05) was observed in the encephalic structures. The increased activities of AChE and BChE probably have a pro-inflammatory purpose, attempting to reduce the concentration of acetylcholine, a neurotransmitter which has an anti-inflammatory property. Therefore, cholinesterase may be inflammatory markers in infection with T. evansi in rabbits.
Assuntos
Acetilcolinesterase/sangue , Butirilcolinesterase/sangue , Tripanossomíase/enzimologia , Doença Aguda , Animais , Biomarcadores/sangue , Doença Crônica , Feminino , Parasitemia/sangue , Coelhos , RatosRESUMO
The aim of this study was to evaluate the nitric oxide (NO()) level, protein oxidation and antioxidant enzymes in rats infected with Trypanosoma evansi and establish the association of NO() levels with the degree of parasitemia. Thirty-six male rats (Wistar) were divided into two groups with 18 animals each. Group A was not infected while Group B was intraperitoneally infected, receiving 7.5×10(6) trypomastigotes per animal. Each group was divided into three subgroups with 6 rats each and blood was collected during different periods post-infection (PI), as follows: day 5 (A(5) and B(5)), day 15 (A(15) and B(15)) and day 30 PI (A(30) and B(30)). Blood samples were collected by cardiac puncture to estimate the levels of nitrites/nitrates (NO(x)) and advanced oxidation protein products (AOPP) in serum, and superoxide dismutase (SOD) and catalase (CAT) activities in blood. On days 15 and 30 PI NO(x) and AOPP levels were increased in serum of rats infected. Rodents infected with T. evansi showed a significant increase in SOD (days 5 and 15 PI) and CAT (day 30 PI) activities. Based on the physiological role of NO(), we can conclude that its increased concentration is related to an inflammatory response against the parasite, once a redox imbalance was observed during infection.
Assuntos
Catalase/metabolismo , Óxido Nítrico/metabolismo , Proteínas/metabolismo , Superóxido Dismutase/metabolismo , Tripanossomíase/metabolismo , Produtos da Oxidação Avançada de Proteínas/análise , Animais , Masculino , Óxido Nítrico/sangue , Oxirredução , Parasitemia/enzimologia , Parasitemia/metabolismo , Ratos , Ratos Wistar , Tripanossomíase/enzimologiaRESUMO
Rangeliosis is a disease which affects dogs in Brazil, caused by a piroplasm known as Rangelia vitalii. This disease causes a lot of clinico-pathological features, including the coagulation disorders associated with bleeding. The cause of these changes has not yet been determined. Considering the association of purinergic system and hemostasis this study aimed to evaluate the activity of enzymes that hydrolyze ATP, ADP and AMP; and deamination of adenosine in platelets from dogs experimentally infected with R. vitalii. For this study, 12 healthy young dogs (females) were used, separated in two groups. Group A (n=5) were uninfected controls, and group B were experimentally infected with R. vitalii (n=7). After being inoculated with R. vitalii-infected blood, animals were monitored by blood smear examinations, which showed intra-erythrocytic forms of the parasite after five days post-inoculation (PI). Blood samples were collected to quantitate and separate platelets (Day 0, 12 and 21 PI) and to measure the enzymatic activities (Day 12 and 21 PI). The activity of NTPDase, 5'-nucleotidase and adenosine deaminase (ADA) was measured in platelets. A reduction (P<0.01) in the number of platelets was observed in R. vitalii-infected blood at Days 12 and 21 PI. At Day 12 PI, a reduction (P<0.01) in the hydrolysis of ATP, ADP and AMP, and deamination of adenosine was observed in dogs infected with R. vitalii. At Day 21 PI the ADA activity remained decreased, unlike the activity of NTPDase which increased (P<0.05). Based on these results we can conclude that ATP, ADP and AMP hydrolysis and adenosine deamination were altered in platelets of R. vitalii-infected dogs. Considering the importance of the purinergic system in hemostasis, it is believed that those changes contribute to the coagulation disorders and bleeding observed in R. vitalii-infected dogs and discussed in this manuscript.
Assuntos
Adenosina Desaminase/sangue , Babesia/fisiologia , Babesiose/veterinária , Plaquetas/enzimologia , Doenças do Cão/sangue , Nucleotidases/sangue , Adenosina/metabolismo , Difosfato de Adenosina/metabolismo , Monofosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Babesiose/sangue , Babesiose/enzimologia , Transtornos da Coagulação Sanguínea/parasitologia , Transtornos da Coagulação Sanguínea/veterinária , Brasil , Desaminação , Doenças do Cão/enzimologia , Doenças do Cão/parasitologia , Cães , Feminino , Hemorragia/parasitologia , Hemorragia/veterinária , Hidrólise , Contagem de Plaquetas/veterináriaRESUMO
The aim of this study was to evaluate lipid peroxidation, protein oxidation and activity of enzymes that are indicators of oxidative stress in Rangelia vitalii infection in dogs. Animals were divided into two groups: negative control (n=5) and infected with R. vitalii (n=7). After inoculation, the parasitemia was estimated daily by microscopic examination of smears. Lipid peroxidation (TBARS) and advanced oxidation protein products (AOPP); and delta-aminolevulinate dehydratase (δ-ALA-D), superoxide dismutase (SOD) and catalase (CAT) activities in blood were evaluated. The samples were collected at days 10 and 20 post-inoculation (PI). TBARS and AOPP levels were higher in the infected group in both analyzed periods (P<0.01). The δ-ALA-D activity was reduced in blood of dogs infected with R. vitalii on days 10 and 20 PI. SOD activity was significantly increased (P<0.01) in the blood of dogs infected with R. vitalii at days 10 and 20 PI, while CAT activity was significantly increased (P<0.01) only at day 20 PI when compared to non-infected animals. A positive correlation was observed between the degree of parasitemia and TBARS and AOPP levels and activity of antioxidant enzymes. The δ-ALA-D activity was negatively correlated with the degree of parasitemia. Based on the increased levels of TBARS, AOPP, SOD and CAT activities, and inhibition δ-ALA-D activity, we concluded that dogs experimentally infected with R. vitalii develop a state of redox unbalance and that these changes might be involved in the pathophysiology of disease.
Assuntos
Apicomplexa/fisiologia , Doenças do Cão/parasitologia , Estresse Oxidativo/fisiologia , Infecções Protozoárias em Animais/parasitologia , Produtos da Oxidação Avançada de Proteínas/metabolismo , Animais , Apicomplexa/classificação , Catalase/genética , Catalase/metabolismo , Cães , Feminino , Regulação Enzimológica da Expressão Gênica , Parasitemia , Sintase do Porfobilinogênio/genética , Sintase do Porfobilinogênio/metabolismo , Infecções Protozoárias em Animais/patologia , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismoRESUMO
The aim of this study was evaluate changes in the cholinesterase activity in blood, lymphocytes and serum of rats infected with Leptospira interrogans serovar Icterohaemorrhagiae ('L. icterohaemorrhagiae'). Sixty adult Wistar rats were divided into six groups of 10 animals: three control groups and three test groups. The animals from the test groups were intraperitoneally inoculated with 1 ml medium containing 1 × 10(8) leptospires. The activity of acetylcholinesterase in blood and butyrylcholinesterase in serum increased on days 5 (P<0.05) and 30 (P<0.021) post-infection, respectively. A decrease in lymphocyte count was observed on days 15 (P<0.01) and 30 post-infection (P<0.05). On day 15 post-infection, acetylcholinesterase activity (P<0.001) in lymphocytes decreased in infected rats. However, on day 30 post-infection there was an increase in acetylcholinesterase activity in lymphocytes. In conclusion, our results showed that the activity of enzymes of the cholinergic system in the total blood, lymphocytes and serum is altered as a result of inflammation caused by infection with L. icterohaemorrhagiae. The possible causes of these alterations will be discussed in this paper.
Assuntos
Acetilcolinesterase/sangue , Butirilcolinesterase/sangue , Leptospira interrogans serovar icterohaemorrhagiae/patogenicidade , Leptospirose/patologia , Linfócitos/enzimologia , Animais , Leptospirose/microbiologia , Contagem de Linfócitos , Masculino , Ratos , Ratos Wistar , Fatores de TempoRESUMO
The aim of this study was to evaluate the platelet count, coagulation time and platelet activity in dogs experimentally infected with Rangelia vitalii during the acute phase of the disease. For this study, 12 young dogs (females) were used, separated in two groups. Group A (uninfected control) was composed by healthy dogs (n=5), and group B consisted of R. vitalii-infected animals (n=7). After being inoculated with R. vitalii-infected blood, animals were monitored by blood smear examinations, which showed intra-erythrocytic forms of the parasite five days post-inoculation (PI). Blood samples were collected on days 0, 10, 20 and 30 PI. The material collected was placed in tubes containing EDTA for quantification of platelets, citrate anticoagulant platelet aggregation, and measuring the clotting time. Right after blood collection on days 10 and 20 PI, dogs were anesthetized for collecting bone marrow samples. A significant reduction (P<0.01) of the number of platelets was observed in R. vitalii-infected blood, when compared with uninfected dogs on days 10 and 20 PI. Additionally, macro-platelets were observed only in infected dogs. Prothrombin time and activated partial thromboplastin time did not differ between infected and uninfected dogs. The megakaryocyte count increased (P<0.01) significantly in infected dogs when compared with uninfected ones on days 10 and 20 PI. Platelet aggregation decreased (P<0.01) significantly in infected dogs in comparison to the control on days 10 and 20 PI. Therefore, rangeliosis in dogs causes a severe thrombocytopenia during the acute phase of infection. This platelets reduction probably occurred due to splenic sequestration and/or immune-mediated thrombocytopenia.
Assuntos
Babesia/classificação , Babesiose/sangue , Plaquetas/fisiologia , Doenças do Cão/parasitologia , Contagem de Plaquetas , Animais , Babesiose/patologia , Doenças do Cão/sangue , Cães , FemininoRESUMO
Nitric oxide (NO) is involved in many physiological processes, such as blood pressure control, neurotransmission, inhibition of platelet and neutrophil adherence, and the ability to kill tumor cells and parasites. The indirect determination of NO can be made by detection of 3-nitrotyrosine (3-NT) residues. The aim of this study was to measure the concentration of 3-NT in the brain of rats experimentally infected with Trypanosoma evansi. Twenty-four were inoculated intraperitoneally with cryopreserved blood containing 1×10(6) trypomastigotes per animal. Twenty-four animals were used as negative controls and received 0.2 mL of saline by the same route. The experimental groups (group C and T) were established according to the time after infection and the degree of parasitemia as follows: four control subgroups (C3, C5, C10 and C20) with six non-inoculated animals each and four test subgroups (T3, T5, T10 and T20) with six animals infected with T. evansi in each group. The animals were anesthetized with isoflurane and subsequently euthanized at the days 3 (C3, T3), 5 (C5, T5), 10 (C10, T10) and 20 (C20, T20) post-infection (PI). The brain was removed and dissected into cerebellum, cerebral cortex, striatum and hippocampus. Concentration of 3-NT in the brain was determined by Slot blot technique. At the day 3 PI no changes were observed in the concentration of 3-NT among the groups. There was a significant reduction (p<0.05) of 3-NT concentration in the striatum and cerebellum at the days 5 and 10 PI, respectively. At the day 20 PI a significant increase (p<0.05) of 3-NT was observed in the cerebellum, cerebral cortex and hippocampus from the infected animals. Therefore, T. evansi infection caused changes in the concentrations of 3-NT in the central nervous system (CNS), which may be related to clinical signs and infection management.
Assuntos
Encéfalo/metabolismo , Tripanossomíase/metabolismo , Tirosina/análogos & derivados , Animais , Estudos de Casos e Controles , Cerebelo/química , Córtex Cerebral/química , Corpo Estriado/química , Cães , Hipocampo/química , Parasitemia/metabolismo , Parasitemia/parasitologia , Ratos , Ratos Wistar , Tripanossomíase/parasitologia , Tirosina/análiseRESUMO
Recently we conducted the molecular characterization of Rangelia vitalii, a protozoan with high pathogenicity for young dogs in southern Brazil. To date, the descriptions of the disease have been restricted to natural infection cases. Therefore, this study aimed to evaluate the parasitemia, biological cycles and clinical-pathological findings in dogs experimentally infected with R. vitalii in the acute phase of disease, and also aimed to test a therapeutic protocol based on the diminazene aceturate. For this study, we used 12 young dogs (females), separated into two groups. Group A was composed of healthy dogs, not-infected (n=5), and Group B consisted of animals infected with R. vitalii (n=7). After infection, the animals were monitored by blood smear examinations, which showed intra-erythrocytic forms of the parasite 5 days post-infection (PI). Parasitemia increased progressively in these animals and had the highest peak of circulating parasites between 9 and 11 days PI. Subsequently, the parasitemia reduced and the protozoan was seen inside the leukocytes in days 17, 19 and 21 PI. The most prominent clinical signs observed at the 20 day PI of experiment were lethargy, fever and anorexia. We observed a decrease of hematocrit of infected animals compared with not-infected dogs, featuring a moderate anemia. Pathological evaluation of one dog in Group B at day 21 PI revealed splenomegaly, hepatomegaly, lymphadenopathy, and hemorrhages at necropsy. Histological examination showed only follicular hyperplasia in the spleen and lymph nodes, and the etiologic agent in the vascular endothelium. At 21 days PI, it was performed the treatment of dogs in Group B (n=6) with a single dose of diminazene aceturate, which showed a curative efficacy of 100% in cleaning R. vitalii from blood of infected dogs.
Assuntos
Apicomplexa/fisiologia , Doenças do Cão/parasitologia , Parasitemia/veterinária , Infecções Protozoárias em Animais/parasitologia , Doença Aguda , Animais , Antiprotozoários/farmacologia , Antiprotozoários/uso terapêutico , Apicomplexa/efeitos dos fármacos , Estudos de Casos e Controles , Diminazena/análogos & derivados , Diminazena/farmacologia , Diminazena/uso terapêutico , Doenças do Cão/tratamento farmacológico , Doenças do Cão/patologia , Cães , Endotélio Vascular/parasitologia , Endotélio Vascular/patologia , Eritrócitos/parasitologia , Feminino , Hematócrito/veterinária , Leucócitos/parasitologia , Masculino , Parasitemia/parasitologia , Infecções Protozoárias em Animais/tratamento farmacológico , Infecções Protozoárias em Animais/patologiaRESUMO
The aim of this study was to measure the levels of interferon-gamma (IFN-γ), tumor necrosis factor-alpha (TNF-α), interleukin 1 (IL-1) and interleukin 6 (IL-6) in the serum of rats experimentally infected with Trypanosoma evansi and to correlate these levels with hematological parameters. Initially, 48 rats (group T) were intraperitoneally inoculated with cryopreserved blood containing 1×10(6) trypomastigotes per animal. Twenty-eight animals (group C) were used as negative controls and received 0.2 mL of saline by the same route. The experimental groups were formed according to the time after infection and the degree of parasitemia as follows: four control subgroups (C3, C5, C10 and C20) with seven non-inoculated animals each and four test subgroups (T3, T5, T10 and T20) with 10 animals each inoculated with T. evansi. The blood samples were collected by cardiac puncture at days 3 (C3, T3), 5 (C5, T5), 10 (C10, T10) and 20 (C20, T20) post-infection (PI) to perform the complete blood count and the determination of IFN-γ, TNF-α, IL-1 and IL-6 levels using an ELISA quantitative sandwich. Infected rats showed normocytic normochromic anemia during the experimental period. T. evansi infection in rats caused a serum increase (P<0.01) of IFN-γ, TNF-α, IL-1 and IL-6 levels at days 3, 5, 10 and 20 PI compared to the controls. The multiple linear regressions showed a reduction of 24% in the hematocrit as a consequence of the increased IFN-γ, TNF-α and IL-1. Therefore, we conclude that the infection caused by T. evansi causes an increase in the pro-inflammatory cytokines. These results suggest a synergism among IL-1, TNF-α and IFN-γ contributing to the development of anemia. This increase is associated with the regulation of immune responses against the parasite.