Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 61
Filtrar
1.
Toxicol Ind Health ; 37(12): 752-762, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34794353

RESUMO

Metalworkers are exposed to numerous chemicals in their workplace environment, such as solvents, heavy metals, and metalworking fluids, that have a negative impact on their health. Furthermore, there is an increase in the prevalence of chronic diseases among metalworkers; however, the molecular mechanisms involved in this increased predisposition to chronic diseases are unclear. Considering that occupational exposure represents a potential risk for metalworkers, the aim of this study was to measure biomarkers of oxidative stress, inflammation, and cytotoxicity in the peripheral blood of metalworkers from Southern Brazil. The study included 40 metalworkers and 20 individuals who did not perform activities with any recognized exposure to chemical substances, such as those working in administration, commerce, and education, as controls. Cellular and molecular biomarkers as leukocyte viability, intracellular production of reactive species, mitochondrial mass and membrane potential and plasma lipid peroxidation, sulfhydryl groups, total antioxidant capacity, and butyrylcholinesterase activity were evaluated in the blood of metalworkers and controls. Metalworkers were found to have higher rates of apoptosis, increased production of reactive species, and increased mitochondrial potential and mass in leukocytes associated with decreased antioxidant defenses and increased activity of the butyrylcholinesterase enzyme in their plasma. It can be concluded that cytotoxicity, oxidative stress, and inflammation are involved in the multiplicity of health outcomes related to chemical exposure in the metalworking industry.


Assuntos
Apoptose/efeitos dos fármacos , Biomarcadores/sangue , Colinérgicos/sangue , Exposição Ocupacional/efeitos adversos , Estresse Oxidativo/efeitos dos fármacos , Adolescente , Adulto , Brasil , Butirilcolinesterase , Estudos Transversais , Feminino , Humanos , Masculino , Ferreiros , Pessoa de Meia-Idade , Adulto Jovem
2.
Microb Pathog ; 107: 1-5, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28286151

RESUMO

The aim of this study was to evaluate whether oxidative stress occurs in rats experimentally infected by Sporothrix schenckii, and its possible effect on disease pathogenesis. Thirty rats were divided into two groups: the group A (uninfected, n = 18) and the group B (infected by S. schenckii, n=21). Blood samples were collected on days 15, 30 and 40 post-infection (PI). At each sampling time, six rats of the group A, and seven of the group B were bled. TBARS (thiobarbituric acid reactive substances) levels in serum samples were measured to evaluate lipid peroxidation. In addition, catalase (CAT) and superoxide dismutase (SOD) activities, known as biomarkers of antioxidants levels, were verified in whole blood. Seric pro-inflammatory cytokine levels were measured (IFN-γ, TNF-α, and IL-6), which showed that these inflammatory mediators were at higher levels in the infected rats (P < 0.001). In comparison to uninfected animals, rats with sporotrichosis showed significantly higher (p < 0.01) levels of TBARS on day 40 PI; CAT activity was significantly increased (p < 0.01) on days 30 and 40 PI; and SOD activity was increased (p < 0.01) on day 40 PI. Infected rats showed larger testicles and granulomas in the testicular capsule, as well as hepatic granulomas and splenic follicular hyperplasia. All tissues (testicle, spleen, and liver) showed inflammation associated with numerous fungal structures. These results demonstrated that the intense inflammatory response (seric and tissue) in sporotrichosis is a likely mechanism for redox imbalance, and consequently cause the oxidative stress in experimentally infected rats.


Assuntos
Estresse Oxidativo/fisiologia , Sporothrix/patogenicidade , Esporotricose/sangue , Esporotricose/metabolismo , Animais , Antioxidantes/análise , Biomarcadores/sangue , Catalase/sangue , Citocinas/sangue , Modelos Animais de Doenças , Granuloma/patologia , Hiperplasia , Inflamação/patologia , Interferon gama/sangue , Interleucina-6/sangue , Peroxidação de Lipídeos , Fígado/patologia , Masculino , Ratos , Soro/enzimologia , Baço/patologia , Esplenopatias , Esporotricose/patologia , Superóxido Dismutase/sangue , Testículo/patologia , Substâncias Reativas com Ácido Tiobarbitúrico/análise , Fator de Necrose Tumoral alfa/sangue
3.
Microb Pathog ; 97: 94-102, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27260685

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/enzimologia
4.
J Neurovirol ; 21(5): 518-24, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26025330

RESUMO

Bovine herpesvirus type 5 (BoHV-5) is the causative agent of herpetic meningoencephalitis in cattle. The purinergic system is described as a modulator of the immune response and neuroinflammation. These functions are related to the extracellular nucleotides concentration. NTPDase and 5'-nucleotidase are enzymes responsible for controlling the extracellular concentration of adenosine triphosphate (ATP), adenosine diphosphate (ADP), adenosine monophosphate (AMP), and adenosine (ADO). The aim of this study is to determinate the ectonucleotidase activity in cortical synaptosomes and synaptosomes from the hippocampus of rabbits experimentally infected with BoHV-5. Rabbits were divided into four groups, two control groups (non-inoculated animals), and two infected groups (inoculated with BoHV-5). The infected groups received 0.5 ml of BoHV-5 suspension with 10(7.5)TCID50 of viral strain SV-507/99, per paranasal sinuses, and the control groups received 0.5 ml of minimum essential media per paranasal sinuses. Animals were submitted to euthanasia on days 7 and 12 post-inoculation (p.i.); cerebral cortex and hippocampus were collected for the synaptosomes isolation and posterior determination of the ectonucleotidase activities. The results showed a decrease (P < 0.05) in ectonucleotidase activity in synaptosomes from the cerebral cortex of infected rabbits, whereas an increased (P < 0.05) ectonucleotidase activity was observed in synaptosomes from the hippocampus. These differences may be related with the heterogeneous distribution of ectonucleotidases in the different brain regions and also with the viral infectivity. Therefore, it is possible to speculate that BoHV-5 replication results in changes in ectonucleotidase activity in the brain, which may contribute to the neurological signs commonly observed in this disease.


Assuntos
Encefalite Viral/enzimologia , Infecções por Herpesviridae/enzimologia , Meningoencefalite/enzimologia , Nucleotidases/metabolismo , Sinaptossomos/enzimologia , Animais , Córtex Cerebral/enzimologia , Córtex Cerebral/virologia , Herpesvirus Bovino 5 , Hipocampo/enzimologia , Hipocampo/virologia , Coelhos
5.
Mol Cell Biochem ; 386(1-2): 199-210, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24130039

RESUMO

This study evaluated the effects of curcumin and/or insulin on antioxidant enzyme activity in blood, liver, and kidney, as well as on lipid peroxidation and delta aminolevulinic dehydratase (δ-ALA-D) activity, and a histopathological analysis of streptozotocin-induced diabetic rats. The animals were divided into six groups (n = 6): control/saline (C); control/curcumin (CCur); diabetic/saline (D); diabetic/insulin (DIns); diabetic/curcumin (DCur); and diabetic/insulin/curcumin (DInsCur). After 30 days of treatment with curcumin and/or insulin, the animals were sacrificed and the liver, kidney, and serum were used for experimental determinations. Results of histopathological analysis showed that the treatment with insulin ameliorate renal and hepatic lesions from both DIns and DInsCur groups. TBARS levels were significantly increased in serum, liver, and kidney in D group and the administration of curcumin and insulin prevented this increase in DIns and DCur groups. The activities of catalase (CAT), superoxide dismutase, and δ-ALA-D presented a significant decrease in the liver and kidney D group when compared to C group (P < 0.05). The animals treated with curcumin and insulin presented an increase of CAT activity, revealing a positive interaction between both substances. The treatments with curcumin or insulin prevented oxidative stress in blood, through modulation of enzymatic antioxidant defenses. These findings contributed to the comprehension that antioxidants from medicinal plants could be used as adjuvant in the treatment of this endocrinopathy and not as single therapy.


Assuntos
Curcumina/administração & dosagem , Diabetes Mellitus Experimental/metabolismo , Insulina/administração & dosagem , Rim/metabolismo , Fígado/metabolismo , Estresse Oxidativo , Animais , Glicemia/análise , Peso Corporal , Catalase/sangue , Diabetes Mellitus Experimental/sangue , Rim/enzimologia , Peroxidação de Lipídeos , Fígado/enzimologia , Masculino , Sintase do Porfobilinogênio/metabolismo , Ratos , Ratos Wistar , Estreptozocina , Superóxido Dismutase/metabolismo
6.
Parasitology ; 141(13): 1761-8, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25111395

RESUMO

SUMMARY The aim of this study was to assess the effect of sulfamethoxazole/trimethoprim (ST) supplemented with diphenyl diselenide and sodium selenite in experimental toxoplasmosis, on oxidant/antioxidant biomarkers and cytokine levels. Eighty-four BALB/c mice were divided in seven groups: group A (negative control), and groups B to G (infected). Blood and liver samples were collected on days 4 and 20 post infection (p.i.). Levels of thiobarbituric acid (TBA) reactive substances and advanced oxidation protein products (AOPP) were assessed in liver samples. Both biomarkers were significantly increased in infected groups on day 4 p.i., while they were reduced on day 20 p.i., compared with group A. Glutathione reductase (GR) activity significantly (P<0·01) increased on day 4 p.i., in group G, compared with group A. INF-γ was significantly increased (P<0·001) in both periods, day 4 (groups B, C, F and G) and 20 p.i. (groups C, F and G). IL-10 significantly reduced (P<0·001) on day 4 p.i. in group B; however, in the same period, it was increased (P<0·001) in groups C and G, compared with group A. On day 20 p.i., IL-10 increased (P<0·001) in groups F and G. Therefore, our results highlighted that these forms of selenium, associated with the chemotherapy, were able to reduce lipid peroxidation and protein oxidation, providing a beneficial immunological balance between the production of pro- and anti-inflammatory cytokines.


Assuntos
Antioxidantes/metabolismo , Derivados de Benzeno/farmacologia , Compostos Organosselênicos/farmacologia , Selenito de Sódio/farmacologia , Toxoplasmose/metabolismo , Animais , Biomarcadores/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Peroxidação de Lipídeos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Oxidantes/metabolismo , Oxirredução , Estresse Oxidativo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
7.
Parasitology ; 140(11): 1432-41, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23965823

RESUMO

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/parasitologia
8.
Exp Parasitol ; 133(3): 357-64, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23270806

RESUMO

The aim of this study was to evaluate biochemical parameters of iron metabolism in rats experimentally infected with Trypanosoma evansi. To this end, 20 rats (Wistar) were intraperitoneally inoculated with blood containing trypomastigotes 10(6) (Group T) and 12 animals were used as negative control (Group C) and received saline (0.2 mL) through same route. Blood samples were collected by cardiac puncture on day 5 (C5, T5) and 30 (C30, T30) post-inoculation (pi) to perform complete blood count and determination of serum iron, transferrin, ferritin, total and latent iron fixation capacity, transferrin saturation and prohepcidin concentration. Also, bone marrow samples were collected, to perform Pearls staining reaction. Levels of iron, total and latent iron binding capacity and prohepcidin concentration were lower (P<0.05) in infected rats (T5 and T30 groups) compared to controls. On the other hand, levels of transferrin and ferritin were higher when compared to controls (P<0.05). The transferrin saturation increased on day 5 pi, but decreased on day 30 pi. The Pearls reaction showed a higher accumulation of iron in the bone marrow of infected animals in day 5 pi (P<0.01). Infection with T. evansi in rats caused anemia and changes in iron metabolism associated to the peaks of parasitemia. These results suggest that changes in iron metabolism may be related to the host immune response to infection and anemic status of infected animals.


Assuntos
Ferro/metabolismo , Tripanossomíase/metabolismo , Anemia Ferropriva/imunologia , Anemia Ferropriva/parasitologia , Animais , Peptídeos Catiônicos Antimicrobianos/sangue , Medula Óssea/metabolismo , Cães , Contagem de Eritrócitos , Índices de Eritrócitos , Ferritinas/metabolismo , Hematócrito , Hemoglobinas/análise , Hemossiderina/metabolismo , Hepcidinas , Sistema Imunitário/metabolismo , Ferro/sangue , Masculino , Parasitemia/imunologia , Parasitemia/parasitologia , Precursores de Proteínas/sangue , Ratos , Ratos Wistar , Transferrina/metabolismo , Trypanosoma/crescimento & desenvolvimento , Tripanossomíase/sangue , Tripanossomíase/complicações , Tripanossomíase/imunologia
9.
Exp Parasitol ; 132(4): 546-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22981718

RESUMO

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/parasitologia
10.
Mycopathologia ; 174(1): 31-9, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22169893

RESUMO

Sporotrichosis is a fungal infection of subcutaneous or chronic evolution, inflammatory lesions characterized by their pyogranulomatous aspect, caused by the dimorphic fungus Sporothrix schenckii. Adenosine deaminase (ADA) is a "key" enzyme in the purine metabolism, promoting the deamination of adenosine, an important anti-inflammatory molecule. The increase in ADA activity has been demonstrated in several inflammatory conditions; however, there are no data in the literature associated with this fungal infection. The objective of this study was to evaluate the activity of serum ADA (S-ADA) and lymphocytes (L-ADA) of rats infected with S. schenckii. We used seventy-eight rats divided into two groups. In the first experiment, rats were infected subcutaneously and in the second experiment, infected intraperitoneally. Blood samples for hematologic evaluation and activities of S-ADA and L-ADA were performed at days 15, 30, and 40 post-infection (PI) to assess disease progression. In the second experiment, it was observed an acute decrease in activity of S-ADA and L-ADA (P < 0.05), suggesting a compensatory mechanism in an attempt to protect the host from excessive tissue damage. With chronicity of disease the rats in the first and second experiment at 30 days PI showed an increased activity of L-ADA (P < 0.05), promoting an inflammatory response in an attempt to combat the spread of the agent. Thus, it is suggested that infection with S. schenckii alters the activities of S-ADA in experimentally infected rats, demonstrating the involvement of this enzyme in the pathogenesis of sporotrichosis.


Assuntos
Adenosina Desaminase/sangue , Interações Hospedeiro-Patógeno , Soro/química , Sporothrix/imunologia , Sporothrix/patogenicidade , Esporotricose/imunologia , Esporotricose/patologia , Animais , Linfócitos/enzimologia , Masculino , Ratos , Ratos Wistar , Fatores de Tempo
11.
Parasitology ; 138(10): 1272-7, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21854703

RESUMO

The aim of this study was to evaluate the activity of delta-aminolevulinate dehydratase (δ-ALA-D) in red blood cells of rats infected with Trypanosoma evansi and establish its association with haematocrit, serum levels of iron and zinc and lipid peroxidation. Thirty-six male rats (Wistar) were divided into 2 groups with 18 animals each. Group A was non-infected while Group B was intraperitoneally infected, receiving 7·5×106 trypomastigotes per animal. Each group was divided into 3 subgroups of 6 rats and blood was collected during different periods post-infection (p.i.) as follows: day 5 (A1 and B1), day 15 (A2 and B2) and day 30 PI (A3 and B3). Blood samples were collected by cardiac puncture to estimate red blood cell parameters (RBC), δ-ALA-D activity and serum levels of iron, zinc and thiobarbituric acid reactive substances (TBARS). Rats in group B showed a significant (P<0·05) reduction of RBC count, haemoglobin concentration and haematocrit at days 5 and 15 p.i. The activity of δ-ALA-D in blood was significantly (P<0·001) increased at days 15 and 30 p.i. δ-ALA-D activity in blood had a significant (P<0·05) negative correlation with haematocrit (r=-0·61) and haemoglobin (r=-0·70) at day 15 p.i. There was a significant (P<0·05) decrease in serum iron and zinc levels and an increase in TBARS levels (P<0·05) during infection. The δ-ALA-D activity in blood was negatively correlated with the levels of iron (r=-0·68) and zinc (r=-0·57) on day 30 p.i. It was concluded that the increased activity of δ-ALA-D in blood might have occurred in response to the anaemia in remission as heme synthesis was enhanced.


Assuntos
Anemia/enzimologia , Sintase do Porfobilinogênio/sangue , Trypanosoma/fisiologia , Tripanossomíase/enzimologia , Anemia/sangue , Anemia/complicações , Anemia/parasitologia , Animais , Contagem de Eritrócitos , Eritrócitos/química , Hematócrito , Hemoglobinas/análise , Ferro/análise , Peroxidação de Lipídeos , Masculino , Parasitemia/sangue , Ratos , Ratos Wistar , Espectrofotometria , Substâncias Reativas com Ácido Tiobarbitúrico/análise , Tripanossomíase/sangue , Tripanossomíase/complicações , Tripanossomíase/parasitologia , Zinco/análise
12.
Exp Parasitol ; 129(1): 27-30, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21679706

RESUMO

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/análise
13.
Exp Parasitol ; 128(4): 365-70, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21557939

RESUMO

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.


Assuntos
Citocinas/sangue , Trypanosoma/imunologia , Tripanossomíase/imunologia , Anemia/imunologia , Anemia/parasitologia , Animais , Contagem de Eritrócitos , Hematócrito , Hemoglobinas/análise , Interferon gama/sangue , Interleucina-1/sangue , Interleucina-6/sangue , Contagem de Leucócitos , Modelos Lineares , Parasitemia/imunologia , Ratos , Ratos Wistar , Tripanossomíase/sangue , Fator de Necrose Tumoral alfa/sangue
14.
Exp Parasitol ; 128(3): 298-300, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21420956

RESUMO

Biochemical and molecular research on parasites has increased considerably in trypanosomes in the recent years. Many of them have the purpose of identify areas, proteins and structures of the parasite which are vulnerable and could be used in therapy against the protozoan. Based on this hypothesis this study aimed to detect biochemically the enzyme adenosine deaminase (ADA) in Trypanosoma evansi, and to adapt an assay to the measurement of its activity in trypomastigotes. Firstly, the parasites were separated from the blood of mice experimentally infected with a DEAE-cellulose column. The ADA activity in trypomastigotes was evaluated at concentrations of 0.1, 0.2, 0.5, 0.6 and 0.8mg of protein by spectrophotometry. ADA activity was observed in the parasites at all concentrations tested and its activity was proportional to the concentration of protein, ranging between 0.64 and 2.24U/L in the lowest and highest concentration of protein, respectively. Therefore, it is possible to detect biochemically ADA in T. evansi, an enzyme that may be associated with vital functions of the parasite, similar to what occurs in mammals. This knowledge may be useful in the association of the chemotherapic treatment with specific inhibitors of the enzyme, in future studies.


Assuntos
Adenosina Desaminase/análise , Trypanosoma/enzimologia , Adenosina/metabolismo , Animais , Cromatografia DEAE-Celulose , Cães , Inosina/metabolismo , Camundongos , Espectrofotometria
15.
Exp Parasitol ; 125(3): 251-5, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20138875

RESUMO

The aim of this study was to evaluate cholinesterase activity during the early acute phase of Trypanosoma evansi infection in rats. Fifteen male Wistar rats were randomly distributed into three groups (n=5 animals per group): two trypanosome-infected groups (T3 and T5) and uninfected controls (C). The animals were inoculated intraperitoneally with 10(6) trypanosomes. The blood was collected by cardiac puncture on the 3rd (T3) or 5th day post-infection (T5 and C). Cerebrum and cerebellum were removed for the evaluation of acetylcholinesterase (AChE) activity. AChE activity was also evaluated in whole blood and butyrylcholinesterase activity (BUChE) in plasma samples. Parasitemia were progressive increase and parasites were observed in the peripheral blood of all infected animals one day post-inoculation. AChE activity was not altered in cerebrum and cerebellum tissues. AChE activity in blood significantly decreased in the T3 and T5 groups (26.63 and 25.86mU/lmolHb) compared with the control (37.84mU/lmolHb). In addition BUChE activity in plasma was lower in the T3 (7.01micromol BTC hydrolyzed/h/mL) than the T5 and C groups (9.84 and 12.00micromol BTC hydrolyzed/h/mL). This study therefore, shows that reductions in the activity of cholinesterase occur in acute infection by T. evansi in rats and this demonstrates an important change occurring in animals infected by the protozoan and may indicate a potential role the enzymes play in the mechanism of disease.


Assuntos
Acetilcolinesterase/metabolismo , Infecções Protozoárias do Sistema Nervoso Central/enzimologia , Trypanosoma/enzimologia , Tripanossomíase/enzimologia , Acetilcolinesterase/sangue , Doença Aguda , Análise de Variância , Animais , Butirilcolinesterase/sangue , Infecções Protozoárias do Sistema Nervoso Central/parasitologia , Cerebelo/enzimologia , Cérebro/enzimologia , Modelos Animais de Doenças , Masculino , Parasitemia/enzimologia , Parasitemia/parasitologia , Distribuição Aleatória , Ratos , Ratos Wistar , Tripanossomíase/sangue , Tripanossomíase/parasitologia
16.
Appl Biochem Biotechnol ; 190(4): 1242-1256, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31735979

RESUMO

Endometritis is an inflammation of the endometrium associated with bacterial infection. The pathogenesis of endometritis in cows is still not completely understood. The combined analysis of the markers of inflammation and oxidative stress has contributed to a better understanding of disease mechanisms, but is still unexplored in uterine disorders. Moreover, research provides evidence about an important role of the vagus nerve in regulating the innate immune function through the cholinergic anti-inflammatory pathway in response to bacterial infections. This new pathway has demonstrated a critical role in controlling the inflammatory system. The aim of this study was to evaluate the activity of cholinesterase in total blood, lymphocytes, and serum of dairy cows with clinical and subclinical endometritis. Sixty-one Holstein cows, between 30 and 45 days in milk, were classified into 3 groups of animals: presenting clinical endometritis (n = 22), subclinical endometritis (n = 17), and healthy (n = 22). Mean leukocyte counts did not differ among groups, but the neutrophil number was significantly higher in cows with clinical endometritis than those in healthy animals. Also, serum concentration of interleukin-1beta (pg/mL) was significantly higher in cows with endometritis. The activity of acetylcholinesterase in blood and lymphocytes increased in both groups with endometritis. Animals with endometritis presented an increase in lipid peroxidation, but the antioxidant enzyme activity (catalase levels) was higher in endometritis groups than in normal cows. In conclusion, the inflammatory process of clinical and subclinical endometritis leads to systemic lipid peroxidation despite the compensatory increase of the antioxidant enzyme. These data also provide evidence of an important role of the cholinergic pathway in regulating dairy cows with clinical and subclinical endometritis.


Assuntos
Doenças dos Bovinos/patologia , Colinesterases/metabolismo , Endometrite/veterinária , Inflamação/metabolismo , Receptores Colinérgicos/metabolismo , Acetilcolinesterase/metabolismo , Animais , Antioxidantes/metabolismo , Butirilcolinesterase/metabolismo , Bovinos , Doenças dos Bovinos/microbiologia , Estudos Transversais , Citocinas/metabolismo , Endometrite/microbiologia , Endometrite/patologia , Endométrio/patologia , Feminino , Sistema Imunitário , Leucócitos/citologia , Peroxidação de Lipídeos , Linfócitos/enzimologia , Estresse Oxidativo , Peroxidase/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Útero/metabolismo
17.
Exp Parasitol ; 123(1): 31-4, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19463818

RESUMO

This study aimed at evaluating hemogram and erythropoietic changes in cats experimentally infected with Trypanosoma evansi. Thirteen adult female non-breeding Felix catus were separated into two groups: seven animals were infected with 10(8) trypomastigotes each, and six animals were used as negative controls. Animals were kept in air-conditioned rooms and blood smears were performed daily for 49 days. Blood samples were collected from the jugular vein at days 0, 7, 21, 35 and 49 and stored in blood-collecting tubes containing anticoagulant. Bone marrow was collected from the proximal epiphysis of the right femur at days 14 and 42 post-inoculation (PI). Total erythrocyte count, hematocrit and hemoglobin showed statistical differences among groups from the seventh day PI onwards (P<0.05). The mean corpuscular volume and the mean corpuscular hemoglobin concentration remained normal, characterizing a normocytic-normochromic anemia. Reticulocyte count increased in the infected group from the 21st day onwards, but remained near normal values suggesting a mild regenerative anemia. Moreover, the myeloid:erythroid ratio significantly reduced at day 42 PI, evidencing a bone marrow hematopoietic response. Based on these results we conclude that cats infected with T. evansi have normocytic, normochromic, regenerative anemia.


Assuntos
Anemia/etiologia , Eritropoese , Parasitemia/sangue , Tripanossomíase/sangue , Tripanossomíase/complicações , Anemia/sangue , Animais , Medula Óssea/fisiologia , Gatos , Contagem de Eritrócitos , Índices de Eritrócitos , Feminino , Hematócrito , Hemoglobinas/análise , Contagem de Reticulócitos
18.
Exp Parasitol ; 123(1): 35-8, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19463819

RESUMO

The aim of this study was to evaluate the concentrations of copper, iron and zinc in blood serum of cats experimentally infected with Trypanosoma evansi. Animals were divided into two groups: control and infected with T. evansi. The animals were infected with 10(8) trypomastigotes each and parasitemia was estimated daily for 56 days by microscopic examination of smears. Hematological and biochemical parameters were evaluated for monitoring of the disease. Serum metal levels were determined in blood samples collected at days 7, 28 and 56 of the experiment. Inductively coupled plasma optical emission spectrometry was used to measure the levels of copper, iron and zinc. Significant differences were observed among groups (P<0.05). Increased levels of copper and decreased iron and zinc levels were observed. A decrease in the number of red blood cells was also observed 7 days after inoculation. Biochemical parameters were not altered. Therefore, the infection by T. evansi might alter the serum metal levels, causing metabolic disturbances in cats.


Assuntos
Cobre/sangue , Ferro/sangue , Parasitemia/sangue , Tripanossomíase/sangue , Zinco/sangue , Animais , Gatos , Contagem de Eritrócitos , Feminino , Hematócrito
19.
Parasitol Res ; 106(1): 157-61, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19789894

RESUMO

The objective of this study was to evaluate the lipid peroxidation and the susceptibility of erythrocytes to in vitro peroxidation as indicators of oxidative damage in erythrocytes and their roles in the pathogenesis of anemia during experimental Trypanosoma evansi infection in cats. Animals were divided into two groups: control and infected with T. evansi. Seven cats were infected with 10(8) trypomastigotes each, and parasitemia was estimated daily for 49 days by microscopic examination of smears. Hematological and biochemical parameters were evaluated for monitoring of the disease. Plasma lipid peroxidation (Thiobarbituric Acid Reactive Substances (TBARS)) and the susceptibility of erythrocytes to in vitro peroxidation were evaluated. Blood samples for analysis were collected at days 21 and 49 post-inoculation. TBARS level, indicated by MDA concentration, was higher in the infected group than in the control group in both analyzed periods, as well as the in vitro erythrocyte peroxidation (P < 0.001). The infected cats had variable degrees of regenerative anemia, which could be explained by the damage in erythrocyte membrane caused by lipid peroxidation.


Assuntos
Doenças do Gato/fisiopatologia , Peroxidação de Lipídeos , Trypanosoma/patogenicidade , Tripanossomíase/fisiopatologia , Animais , Doenças do Gato/parasitologia , Gatos , Modelos Animais de Doenças , Contagem de Eritrócitos , Eritrócitos/efeitos dos fármacos , Feminino , Contagem de Leucócitos , Oxidantes/toxicidade , Plasma/química
20.
Parasitol Int ; 73: 101948, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31247308

RESUMO

This study aimed to evaluate nucleoside triphosphate diphosphohydrolase (NTPDase) and adenosine deaminase (ADA) activities in lymphocytes from rats supplemented or not with curcumin 30 days prior to experimental infection with Trypanosoma evansi. Thirty-two adult male Wistar rats were divided in four groups. The pre-infection group 20 (PreI20) received orally 20 mg/kg of curcumin and pre-infection group 60 (PreI60) received orally 60 mg/kg of curcumin for 30 days prior inoculation with T. evansi. The infected e non-infected control groups received only oral vehicle for 30 days. Trypanosoma evansi infected groups were inoculated intraperitoneally with 0.2 ml of blood with 1 × 106 parasites. After inoculation the treatment of the groups continued until the day of euthanasia (15 days). The results showed that curcumin pre-treatment, with both doses, reduced (P < .05) NTPDase and increased (P < .05) ADA activity in lymphocytes of treated groups when compared to untreated and infected animals (control). The results of this study support the evidence that the regulation of ATP and adenosine levels by NTPDase and ADA activities appear to be important to modulate the immune response in T. evansi infection, once the treatment with curcumin maintained the NTPDase activity reduced and enhanced ADA activity in lymphocytes. It is possible to conclude that the use of curcumin prior to infection with T. evansi induces immunomodulatory effects, favoring the response against the parasite.


Assuntos
Nucleotídeos de Adenina/metabolismo , Adenosina Trifosfatases/metabolismo , Curcumina/metabolismo , Imunomodulação/efeitos dos fármacos , Tripanossomíase/metabolismo , Ração Animal/análise , Animais , Curcumina/administração & dosagem , Dieta/veterinária , Suplementos Nutricionais/análise , Relação Dose-Resposta a Droga , Linfócitos/parasitologia , Masculino , Distribuição Aleatória , Ratos , Ratos Wistar , Trypanosoma/fisiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA