RESUMO
Nucleotide excision repair (NER) acts repairing damages in DNA, such as lesions caused by cisplatin. Xeroderma Pigmentosum complementation group C (XPC) protein is involved in recognition of global genome DNA damages during NER (GG-NER) and it has been studied in different organisms due to its importance in other cellular processes. In this work, we studied NER proteins in Trypanosoma cruzi and Trypanosoma evansi, parasites of humans and animals respectively. We performed three-dimensional models of XPC proteins from T. cruzi and T. evansi and observed few structural differences between these proteins. In our tests, insertion of XPC gene from T. evansi (TevXPC) in T. cruzi resulted in slower cell growth under normal conditions. After cisplatin treatment, T. cruzi overexpressing its own XPC gene (TcXPC) was able to recover cell division rates faster than T. cruzi expressing TevXPC gene. Based on these tests, it is suggested that TevXPC (being an exogenous protein in T. cruzi) interferes negatively in cellular processes where TcXPC (the endogenous protein) is involved. This probably occurred due interaction of TevXPC with some endogenous molecules or proteins from T. cruzi but incapacity of interaction with others. This reinforces the importance of correctly XPC functioning within the cell.
O reparo por excisão de nucleotídeos (NER) atua reparando danos no DNA, como lesões causadas por cisplatina. A proteína Xeroderma Pigmentosum complementation group C (XPC) está envolvida no reconhecimento de danos pela via de reparação global do genoma pelo NER (GG-NER) e tem sido estudada em diferentes organismos devido à sua importância em outros processos celulares. Neste trabalho, estudamos proteínas do NER em Trypanosoma cruzi e Trypanosoma evansi, parasitos de humanos e animais, respectivamente. Modelos tridimensionais das proteínas XPC de T. cruzi e T. evansi foram feitos e observou-se poucas diferenças estruturais entre estas proteínas. Durante testes, a inserção do gene XPC de T. evansi (TevXPC) em T. cruzi resultou em crescimento celular mais lento em condições normais. Após o tratamento com cisplatina, T. cruzi superexpressando seu próprio gene XPC (TcXPC) foi capaz de recuperar as taxas de divisão celular mais rapidamente do que T. cruzi expressando o gene TevXPC. Com base nesses testes, sugere-se que TevXPC (sendo uma proteína exógena em T. cruzi) interfere negativamente nos processos celulares em que TcXPC (a proteína endógena) está envolvida. Isso provavelmente ocorreu pois TevXPC é capaz de interagir com algumas moléculas ou proteínas endógenas de T. cruzi, mas é incapaz de interagir com outras. Isso reforça a importância do correto funcionamento de XPC dentro da célula.
Assuntos
Animais , Cruzamentos Genéticos , Dano ao DNA , Expressão Gênica , Trypanosoma cruzi/genéticaRESUMO
Abstract Nucleotide excision repair (NER) acts repairing damages in DNA, such as lesions caused by cisplatin. Xeroderma Pigmentosum complementation group C (XPC) protein is involved in recognition of global genome DNA damages during NER (GG-NER) and it has been studied in different organisms due to its importance in other cellular processes. In this work, we studied NER proteins in Trypanosoma cruzi and Trypanosoma evansi, parasites of humans and animals respectively. We performed three-dimensional models of XPC proteins from T. cruzi and T. evansi and observed few structural differences between these proteins. In our tests, insertion of XPC gene from T. evansi (TevXPC) in T. cruzi resulted in slower cell growth under normal conditions. After cisplatin treatment, T. cruzi overexpressing its own XPC gene (TcXPC) was able to recover cell division rates faster than T. cruzi expressing TevXPC gene. Based on these tests, it is suggested that TevXPC (being an exogenous protein in T. cruzi) interferes negatively in cellular processes where TcXPC (the endogenous protein) is involved. This probably occurred due interaction of TevXPC with some endogenous molecules or proteins from T.cruzi but incapacity of interaction with others. This reinforces the importance of correctly XPC functioning within the cell.
Resumo O reparo por excisão de nucleotídeos (NER) atua reparando danos no DNA, como lesões causadas por cisplatina. A proteína Xeroderma Pigmentosum complementation group C (XPC) está envolvida no reconhecimento de danos pela via de reparação global do genoma pelo NER (GG-NER) e tem sido estudada em diferentes organismos devido à sua importância em outros processos celulares. Neste trabalho, estudamos proteínas do NER em Trypanosoma cruzi e Trypanosoma evansi, parasitos de humanos e animais, respectivamente. Modelos tridimensionais das proteínas XPC de T. cruzi e T. evansi foram feitos e observou-se poucas diferenças estruturais entre estas proteínas. Durante testes, a inserção do gene XPC de T. evansi (TevXPC) em T. cruzi resultou em crescimento celular mais lento em condições normais. Após o tratamento com cisplatina, T. cruzi superexpressando seu próprio gene XPC (TcXPC) foi capaz de recuperar as taxas de divisão celular mais rapidamente do que T. cruzi expressando o gene TevXPC. Com base nesses testes, sugere-se que TevXPC (sendo uma proteína exógena em T. cruzi) interfere negativamente nos processos celulares em que TcXPC (a proteína endógena) está envolvida. Isso provavelmente ocorreu pois TevXPC é capaz de interagir com algumas moléculas ou proteínas endógenas de T.cruzi, mas é incapaz de interagir com outras. Isso reforça a importância do correto funcionamento de XPC dentro da célula.
RESUMO
Abstract Nucleotide excision repair (NER) acts repairing damages in DNA, such as lesions caused by cisplatin. Xeroderma Pigmentosum complementation group C (XPC) protein is involved in recognition of global genome DNA damages during NER (GG-NER) and it has been studied in different organisms due to its importance in other cellular processes. In this work, we studied NER proteins in Trypanosoma cruzi and Trypanosoma evansi, parasites of humans and animals respectively. We performed three-dimensional models of XPC proteins from T. cruzi and T. evansi and observed few structural differences between these proteins. In our tests, insertion of XPC gene from T. evansi (TevXPC) in T. cruzi resulted in slower cell growth under normal conditions. After cisplatin treatment, T. cruzi overexpressing its own XPC gene (TcXPC) was able to recover cell division rates faster than T. cruzi expressing TevXPC gene. Based on these tests, it is suggested that TevXPC (being an exogenous protein in T. cruzi) interferes negatively in cellular processes where TcXPC (the endogenous protein) is involved. This probably occurred due interaction of TevXPC with some endogenous molecules or proteins from T.cruzi but incapacity of interaction with others. This reinforces the importance of correctly XPC functioning within the cell.
Resumo O reparo por excisão de nucleotídeos (NER) atua reparando danos no DNA, como lesões causadas por cisplatina. A proteína Xeroderma Pigmentosum complementation group C (XPC) está envolvida no reconhecimento de danos pela via de reparação global do genoma pelo NER (GG-NER) e tem sido estudada em diferentes organismos devido à sua importância em outros processos celulares. Neste trabalho, estudamos proteínas do NER em Trypanosoma cruzi e Trypanosoma evansi, parasitos de humanos e animais, respectivamente. Modelos tridimensionais das proteínas XPC de T. cruzi e T. evansi foram feitos e observou-se poucas diferenças estruturais entre estas proteínas. Durante testes, a inserção do gene XPC de T. evansi (TevXPC) em T. cruzi resultou em crescimento celular mais lento em condições normais. Após o tratamento com cisplatina, T. cruzi superexpressando seu próprio gene XPC (TcXPC) foi capaz de recuperar as taxas de divisão celular mais rapidamente do que T. cruzi expressando o gene TevXPC. Com base nesses testes, sugere-se que TevXPC (sendo uma proteína exógena em T. cruzi) interfere negativamente nos processos celulares em que TcXPC (a proteína endógena) está envolvida. Isso provavelmente ocorreu pois TevXPC é capaz de interagir com algumas moléculas ou proteínas endógenas de T.cruzi, mas é incapaz de interagir com outras. Isso reforça a importância do correto funcionamento de XPC dentro da célula.
Assuntos
Humanos , Animais , Trypanosoma cruzi/genética , Xeroderma Pigmentoso , Dano ao DNA/genética , Biologia Computacional , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Reparo do DNA/genéticaRESUMO
Nucleotide excision repair (NER) acts repairing damages in DNA, such as lesions caused by cisplatin. Xeroderma Pigmentosum complementation group C (XPC) protein is involved in recognition of global genome DNA damages during NER (GG-NER) and it has been studied in different organisms due to its importance in other cellular processes. In this work, we studied NER proteins in Trypanosoma cruzi and Trypanosoma evansi, parasites of humans and animals respectively. We performed three-dimensional models of XPC proteins from T. cruzi and T. evansi and observed few structural differences between these proteins. In our tests, insertion of XPC gene from T. evansi (TevXPC) in T. cruzi resulted in slower cell growth under normal conditions. After cisplatin treatment, T. cruzi overexpressing its own XPC gene (TcXPC) was able to recover cell division rates faster than T. cruzi expressing TevXPC gene. Based on these tests, it is suggested that TevXPC (being an exogenous protein in T. cruzi) interferes negatively in cellular processes where TcXPC (the endogenous protein) is involved. This probably occurred due interaction of TevXPC with some endogenous molecules or proteins from T. cruzi but incapacity of interaction with others. This reinforces the importance of correctly XPC functioning within the cell.(AU)
O reparo por excisão de nucleotídeos (NER) atua reparando danos no DNA, como lesões causadas por cisplatina. A proteína Xeroderma Pigmentosum complementation group C (XPC) está envolvida no reconhecimento de danos pela via de reparação global do genoma pelo NER (GG-NER) e tem sido estudada em diferentes organismos devido à sua importância em outros processos celulares. Neste trabalho, estudamos proteínas do NER em Trypanosoma cruzi e Trypanosoma evansi, parasitos de humanos e animais, respectivamente. Modelos tridimensionais das proteínas XPC de T. cruzi e T. evansi foram feitos e observou-se poucas diferenças estruturais entre estas proteínas. Durante testes, a inserção do gene XPC de T. evansi (TevXPC) em T. cruzi resultou em crescimento celular mais lento em condições normais. Após o tratamento com cisplatina, T. cruzi superexpressando seu próprio gene XPC (TcXPC) foi capaz de recuperar as taxas de divisão celular mais rapidamente do que T. cruzi expressando o gene TevXPC. Com base nesses testes, sugere-se que TevXPC (sendo uma proteína exógena em T. cruzi) interfere negativamente nos processos celulares em que TcXPC (a proteína endógena) está envolvida. Isso provavelmente ocorreu pois TevXPC é capaz de interagir com algumas moléculas ou proteínas endógenas de T. cruzi, mas é incapaz de interagir com outras. Isso reforça a importância do correto funcionamento de XPC dentro da célula.(AU)
Assuntos
Animais , Dano ao DNA , Trypanosoma cruzi/genética , Cruzamentos Genéticos , Expressão GênicaRESUMO
The infectivity and virulence of seven Trypanosoma evansi and Trypanosoma equiperdum Venezuelan strains isolated from horses, donkeys and capybaras were compared in a mouse model up to 41â¯days, for parasitemia, animal weight, survival rates, packed cell volume, haemoglobin and erythrocyte count. Two T. equiperdum strains and three of the T. evansi strains resulted in 100% mice mortality, while the two T. evansi donkey strains exhibited lower infectivity and mortality. T. equiperdum strains had shorter pre-patent periods (4â¯days) than the T. evansi strains (4-12â¯days). In terms of pathogenicity, only the T. evansi horse strain and the two capybara strains produced a significant decrease of the packed cell volume, in haemoglobin concentration and in red blood cell count. In contrast, the T. evansi donkey strains did not show any changes in the hematological parameters. From the seven variables studied, only pre-patent period, day of maximum parasitemia, day of first parasitemia peak and number of parasitemia peaks were statistically significant. Weight decrease was only observed in mice infected with the T. evansi horse strain. T. equiperdum strains showed the highest mice lethality (7% survival by day 8 post-infection) with no change in the hematological parameters. The three T. evansi horse and capybara strains showed 80%, 87% and 97% survival rates, respectively by day 12 post-infection. However, by day 20 post-inoculation all the mice infected with the T. evansi horse strain died, while 53% and 27% capybara strains infected survived. Whereas by day 40 post-infection, 53 and 73% of the mice infected with the T. evansi donkey strains had survived. These results demonstrate striking infectivity and virulence differences between Venezuelan T. evansi and T. equiperdum strains in NMRI mice and open new possibilities to characterize inter and intra-species variations that may contribute to the pathogenicity of these two species.
Assuntos
Trypanosoma/patogenicidade , Tripanossomíase/veterinária , Anemia/etiologia , Animais , Modelos Animais de Doenças , Equidae/parasitologia , Cavalos/parasitologia , Camundongos , Roedores/parasitologia , Tripanossomíase/mortalidade , VirulênciaRESUMO
In South America, capybaras (Hydrochoerus hydrochaeris) as well as coatis (Nasua nasua) are the reservoir hosts of Trypanosoma evansi. Capybaras from a T. evansi nonendemic area in the State of São Paulo, southeastern Brazil, were culled because of an ongoing outbreak of Brazilian spotted fever; serum samples from these capybaras were tested for antibodies to T. evansi. Of the 172 sera tested, 17 (9.9%) were seropositive by card agglutination test, with antibody titers of 1:8-1:128; 14 (8.1%) of these 17 seropositive sera were also seropositive by indirect fluorescent antibody test, with antibody titers of 1:16-1:256. Both serologic techniques proved to be efficient, with similar results for detection of antibodies to T. evansi in capybaras from a nonendemic area in Brazil.
Assuntos
Roedores , Trypanosoma/isolamento & purificação , Tripanossomíase/veterinária , Testes de Aglutinação/veterinária , Animais , Brasil/epidemiologia , Estudos Soroepidemiológicos , Tripanossomíase/epidemiologiaRESUMO
Background: Trypanosomosis is a disease caused by a flagellate protozoan known as Trypanosoma evansi, transmitted by hematophagous insects. It parasites showed a large diversity of mammalian hosts. Dogs may show clinical changes such as weight loss, progressive weakness, anorexia, anemia, intermittent fever, conjunctivitis, swelling of limbs and increased of superficial lymph nodes. Treatment of trypanosomosis relies on the use of diminazene aceturate which is effective for the treatment of disease in infected animals. However, a single dose of drug are not effective for horses, mules and dogs, since drug neither cross the blood-brain barrier or has insufficient doses to control the T. evansi infection. Therefore, the present study aimed to report the curative efficacy of a new therapeutic protocol, based on diminazene aceturate, for dogs infected with T. evansi. Case: The treatment against trypanosomosis was performed in a dog, male, two years old, from the municipality of Uruguaiana, RS, Brazil.. The animal showing clinical signs such as apathy, vomit, increase of left submandibular lymph node, edema of the left face and change of gait in the hind limbs when it was evaluated by veterinarians. The hematological and biochemical parameters revealed normocytic-hypochromic anemia, thrombocytopenia, hyperglobulinemia and hypoalbuminemia. Trypomastigotes of T. evansi were identified in blood smears stained by panoptic method. The parasitism by T. evansi was confirmed by blood inoculation in two rats (xenodiagnosis) and by PCR T. evansi-specific. The canine was treated with diminazene aceturate (intramuscular injection) using a dose of 3.5 mg kg-1 for 5 days at 24h of intervals. After treatment the dog showed clinical signs of health improvement, and clinical signs disappeared after the seventh day of treatment. The parasite was not found in blood smears after the third day of treatment and PCR was negative on days 30 and 50 post-treatment. During the treatment signs of drug intoxication were not observed, as well as hepatic and renal functions were not affected. The animal showed normal biochemical and hematological parameters after 30 days of treatment. Discussion: In this study, the treatment tested was effective, leading to the cure of the disease. Previously, the same protocol was used for cats experimentally infected with T. evansi, obtaining 85.7% (6/7) of curative efficacy. In a comparative study of doses of diminazene aceturate in rats infected with T. evansi, inefficiency and death of rats treated with a single dose of 3.5 and 7.0 mg kg-1 were observed. In contrast, the cure in rats occurred when animals received a dose of 3.5 and 7.0 mg kg-1 during five consecutive days. The return of the parasitemia after treatment may be related to the impossibility of the medicament pass through the blood-brain barrier or the doses is insufficient. Our data reveal that five-dose protocol obtained higher efficiency because it provided greater passage of drug molecules through blood-brain barrier, which could eliminate the parasite from brain. After treatment, all clinical signs disappeared, biochemical and hematological parameters returned to normal levels, allowing us to conclude that this new protocol tested was effective to cure of this disease in dogs.
Assuntos
Masculino , Animais , Cães , Diminazena/uso terapêutico , Protocolos Clínicos/normas , Tripanossomíase/veterinária , Reação em Cadeia da Polimerase/veterináriaRESUMO
Background: Trypanosomosis is a disease caused by a flagellate protozoan known as Trypanosoma evansi, transmitted by hematophagous insects. It parasites showed a large diversity of mammalian hosts. Dogs may show clinical changes such as weight loss, progressive weakness, anorexia, anemia, intermittent fever, conjunctivitis, swelling of limbs and increased of superficial lymph nodes. Treatment of trypanosomosis relies on the use of diminazene aceturate which is effective for the treatment of disease in infected animals. However, a single dose of drug are not effective for horses, mules and dogs, since drug neither cross the blood-brain barrier or has insufficient doses to control the T. evansi infection. Therefore, the present study aimed to report the curative efficacy of a new therapeutic protocol, based on diminazene aceturate, for dogs infected with T. evansi. Case: The treatment against trypanosomosis was performed in a dog, male, two years old, from the municipality of Uruguaiana, RS, Brazil.. The animal showing clinical signs such as apathy, vomit, increase of left submandibular lymph node, edema of the left face and change of gait in the hind limbs when it was evaluated by veterinarians. The hematological and biochemical parameters revealed normocytic-hypochromic anemia, thrombocytopenia, hyperglobulinemia and hypoalbuminemia. Trypomastigotes of T. evansi were identified in blood smears stained by panoptic method. The parasitism by T. evansi was confirmed by blood inoculation in two rats (xenodiagnosis) and by PCR T. evansi-specific. The canine was treated with diminazene aceturate (intramuscular injection) using a dose of 3.5 mg kg-1 for 5 days at 24h of intervals. After treatment the dog showed clinical signs of health improvement, and clinical signs disappeared after the seventh day of treatment. The parasite was not found in blood smears after the third day of treatment and PCR was negative on days 30 and 50 post-treatment. During the treatment signs of drug intoxication were not observed, as well as hepatic and renal functions were not affected. The animal showed normal biochemical and hematological parameters after 30 days of treatment. Discussion: In this study, the treatment tested was effective, leading to the cure of the disease. Previously, the same protocol was used for cats experimentally infected with T. evansi, obtaining 85.7% (6/7) of curative efficacy. In a comparative study of doses of diminazene aceturate in rats infected with T. evansi, inefficiency and death of rats treated with a single dose of 3.5 and 7.0 mg kg-1 were observed. In contrast, the cure in rats occurred when animals received a dose of 3.5 and 7.0 mg kg-1 during five consecutive days. The return of the parasitemia after treatment may be related to the impossibility of the medicament pass through the blood-brain barrier or the doses is insufficient. Our data reveal that five-dose protocol obtained higher efficiency because it provided greater passage of drug molecules through blood-brain barrier, which could eliminate the parasite from brain. After treatment, all clinical signs disappeared, biochemical and hematological parameters returned to normal levels, allowing us to conclude that this new protocol tested was effective to cure of this disease in dogs.(AU)