RESUMO
Adrenocortical disturbances are associated with canine ehrlichiosis due to the immunological changes caused by infection and consequent inflammation. Thus, this study aimed to evaluate the occurrence of adrenocortical hormonal changes in dogs naturally infected with Ehrlichia canis (n=21) as confirmed by the presence of anti-E. canis antibodies (Dot-ELISA) and nested PCR (nPCR). Serum cortisol concentrations were assessed by radioimmunoassay before and one hour after ACTH stimulation. Ten healthy dogs were subjected to the same stimulation protocol and used as controls. The results revealed that the dogs with naturally acquired acute and subclinical ehrlichiosis secreted cortisol following ACTH stimulation in similar concentrations to those of healthy dogs.
Assuntos
Animais , Cães , Ehrlichia canis/efeitos dos fármacos , Hidrocortisona , Hormônio Adrenocorticotrópico/administração & dosagem , Hormônio Adrenocorticotrópico/análise , Ehrlichiose/veterinária , Reação em Cadeia da Polimerase/veterináriaRESUMO
Adrenocortical disturbances are associated with canine ehrlichiosis due to the immunological changes caused by infection and consequent inflammation. Thus, this study aimed to evaluate the occurrence of adrenocortical hormonal changes in dogs naturally infected with Ehrlichia canis (n=21) as confirmed by the presence of anti-E. canis antibodies (Dot-ELISA) and nested PCR (nPCR). Serum cortisol concentrations were assessed by radioimmunoassay before and one hour after ACTH stimulation. Ten healthy dogs were subjected to the same stimulation protocol and used as controls. The results revealed that the dogs with naturally acquired acute and subclinical ehrlichiosis secreted cortisol following ACTH stimulation in similar concentrations to those of healthy dogs.(AU)
Assuntos
Animais , Cães , Ehrlichia canis/efeitos dos fármacos , Hidrocortisona , Hormônio Adrenocorticotrópico/administração & dosagem , Hormônio Adrenocorticotrópico/análise , Ehrlichiose/veterinária , Reação em Cadeia da Polimerase/veterináriaRESUMO
The aim of this study was to evaluate adenosine deaminase activity and purines levels in serum of dogs experimentally infected by Ehrlichia canis. Banked serum samples of dogs divided into two groups with five animals each: healthy animals and animals infected by E. canis. The concentration of purines (adenosine triphosphate (ATP), adenosine diphosphate (ADP), adenosine monophosphate (AMP), adenosine, inosine, hypoxanthine, xanthine and uric acid), and adenosine deaminase (E-ADA) activity in sera were evaluated. Samples were collected on days 12 and 30 post-infection (PI). The E-ADA activity showed a significant reduction on day 12 PI, and increased on day 30 PI in dogs infected with E. canis. On day 12, an increase in seric concentration of ATP, ADP and adenosine was verified, and different levels of hypoxanthine, xanthine and uric acid had a drastic reduction in infected compared healthy dogs (P<0.05). However, on day 30 PI, the levels of seric ADP and AMP decreased, unlike the concentration of xanthine and uric acid that increased significantly in infected dogs (P<0.05). Therefore, the activity of E-ADA and purine levels are altered in experimental canine ehrlichiosis, probably with the purpose of modulating the pathogenesis of the disease related to immune response, oxidative stress and coagulation disorders in acute phase.
Assuntos
Adenosina Desaminase/sangue , Doenças do Cão/enzimologia , Ehrlichia canis/fisiologia , Ehrlichiose/veterinária , Purinas/sangue , Animais , Doenças do Cão/sangue , Doenças do Cão/microbiologia , Cães , Ehrlichia canis/patogenicidade , Ehrlichiose/sangue , Ehrlichiose/enzimologia , Ehrlichiose/microbiologia , VirulênciaRESUMO
The aim of this study was to evaluate nitric oxide levels, lipid peroxidation, protein oxidation and glutathione reductase activity in serum of dogs experimentally infected by Ehrlichia canis. Banked serum samples of dogs divided into two groups were used: negative control (n=5) and infected by E. canis (n=5). The concentration of nitrite/nitrate (NOx), lipid peroxidation (TBARS), advanced oxidation protein products (AOPP), and glutathione reductase (GR) activity in sera were evaluated. Samples were collected on days 0, 3, 6, 18 and 30 post-infection (PI). NOx and TBARS levels were significantly (P<0.05) higher in the infected group at 18 and 30 days PI, as well as AOPP levels at 30 days PI when compared to samples from control group. The GR activity was significant (P<0.05) increased in serum of dogs infected by E. canis on days 18 and 30 PI. Based on the increased levels of NOx, TBARS, AOPP and GR activity we concluded that dogs experimentally infected by E. canis develop a state of redox imbalance and that these changes might be involved in the pathophysiology of the disease.
Assuntos
Doenças do Cão/patologia , Ehrlichia canis/fisiologia , Ehrlichiose/veterinária , Óxido Nítrico/metabolismo , Estresse Oxidativo/fisiologia , Animais , Cães , Ehrlichiose/patologia , FemininoRESUMO
Hepatozoonosis is a tick-borne disease whose transmission to dogs occurs by ingestion of oocysts infected ticks or feeding on preys infested by infected ticks. Until now, there is no previous report of molecular characterization of Hepatozoon sp. in dogs from Colombia. EDTA blood samples were collected from 91 dogs from central-western region of Colombia (Bogotá, Bucaramanga, and Villavicencio cities) and submitted to 18S rRNA Hepatozoon sp. PCR and blood smears confection. Phylogenetic analysis was used to access the identity of Hepatozoon species found in sampled dogs. From 91 sampled dogs, 29 (31.8%) were positive to Hepatozoon sp. (25 dogs were only positive in PCR, 1 was positive only in blood smears, and 3 were positive in both blood smears and PCR). After sequencing, the found Hepatozoon sp. DNA showed 100% of identity with Hepatozoon canis DNA isolates. The phylogenetic tree supported the identity of the found Hepatozoon sp. DNA, showing that the isolates from Colombia were placed in the same clade than other H. canis isolates from Venezuela, Spain, and Taiwan. This is the first molecular detection of H. canis in dogs from Colombia.
Assuntos
Coccídios/classificação , Coccídios/isolamento & purificação , Coccidiose/veterinária , Doenças do Cão/parasitologia , Animais , Sangue/parasitologia , Análise por Conglomerados , Coccídios/genética , Coccidiose/parasitologia , Colômbia , DNA de Protozoário/química , DNA de Protozoário/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Cães , Genes de RNAr , Filogenia , RNA de Protozoário/genética , RNA Ribossômico 18S/genética , Análise de Sequência de DNARESUMO
Canine ehrlichiosis is caused by the bacterium Ehrlichia canis and is characterized by a systemic febrile disease of unknown pathogenesis. This study evaluated the expression of cytokines TNF-α, IL-10, IFN-γ, in splenic cells and blood leukocytes during the acute phase of ehrlichiosis and after treatment with doxycycline hyclate in dogs experimentally infected with the E. canis Jaboticabal strain. The study results showed a significant expression of TNF-α 18 days post-inoculation, reducing by approximately 70% after treatment. There was a unique peak of expression of IL-10 and IFN-γ 18 and 30 days post-inoculation, respectively. This study suggests that TNF-α plays a role in the pathogenesis of the acute phase of canine ehrlichiosis and that treatment with doxycycline hyclate reduces the systemic effects of this cytokine, possibly by reducing or eliminating parasitemia. (AU)
A erliquiose canina é causada pela bactéria Ehrlichia canis, que desencadeia no hospedeiro uma doença febril e sistêmica, de patogênese pouco conhecida. O presente estudo avaliou a expressão das citocinas TNF-α, IL-10, IFN-γ, em células esplênicas e em leucócitos sanguíneos, durante a fase aguda da erliquiose e após o tratamento com hiclato de doxiciclina, em cães experimentalmente infectados com a amostra E. canis Jaboticabal. Os resultados mostraram expressão significativa de TNF-α 18 dias após a inoculação, reduzindo aproximadante 70% após o tratamento. Houve um único pico de expressão de IL-10 e de IFN-γ entre 18 e 30 dias após a inoculação, respectivamente. Este estudo sugere que o TNF-α participa da patogenia da fase aguda da erliquiose canina, e que o tratamento com hiclato de doxiciclina reduz os efeitos sistêmicos dessa citocina, possivelmente por reduzir ou eliminar a parasitemia. (AU)
Assuntos
Cães , Ehrlichia canis/isolamento & purificação , Ehrlichiose , Cães/imunologia , Cães/parasitologia , Leucócitos , Citocinas/análise , Doxiciclina/uso terapêutico , Infecções/veterináriaRESUMO
O objetivo desse estudo foi comparar a pesquisa de mórulas de Ehrlichia canis e a nPCR em sangue total e em aspirado de baço. Selecionaram-se 40 cães apresentando trombocitopenia associada a sinais e sintomas sugestivos de erliquiose canina. A pesquisa de mórula mostrou que dentre 35 amostras, 17 apresentaram mórulas nas preparações do baço, e duas nos esfregaços feitos a partir da papa leucocitária. O DNA de Ehrlichia canis foi detectado em 29 de 40 amostras de baço e em 30 de 40 no sangue. No presente estudo observou-se que a pesquisa de mórula é mais eficiente nas preparações citológicas obtidas da punção aspirativa do baço e que tanto a nPCR de baço quanto a de sangue foram eficientes no diagnóstico da doença.(AU)
The aim of this study was to compare the detection of Ehrlichia canis morulae and DNA by nPCR in whole blood and spleen aspiration. The sample included 40 dogs showing thrombocytopenia associated to clinical signs suggestive of canine ehrlichiosis. Morulae detection showed that in 35 of the dogs studied, 17 had morulae in spleen tissue, and two in buffy coat smears. E. canis DNA was detected in 29/40 blood samples. We verified that morulae detection is more efficient in cytological preparations from spleen aspiration. On the other hand, nPCR on spleen and blood samples were equally efficient for disease diagnosis.(AU)