Activities of ectonucleotidases and adenosine deaminase in platelets of cattle experimentally infected by Fasciola hepatica.

The enzymatic activities of NTPDase, 5'-nucleotidase and adenosine deaminase (ADA) are important in regulating the concentration of adenine nucleotides, molecules known to be involved on platelet aggregation. Fasciolosis causes coagulation disorders that have not been completely elucidated. Taking into consideration the association between the purinergic system and hemostasis, this study aimed to evaluate the enzymatic activities of NTPDase (hydrolyze ATP and ADP), 5'-nucleotidase (hydrolyze AMP) and ADA (deamination of adenosine) in platelets from cattle experimentally infected by Fasciola hepatica on days 20, 40, 60 and 80 post-infection (PI). For this study, 10 healthy Friesian steers were separated into two groups: the group A (n = 5) was used as uninfected control, and the group B was composed of steers experimentally infected by F. hepatica (n = 5). The number of platelets did not differ between groups in the periods evaluated. Reduction of NTPDase (p < 0.05) hydrolysing ATP (days 20, 40 and 60 PI), and ADP (days 40, 60 and 80 PI), and on 5'-nucleotidase hydrolyzing AMP (days 40 and 60 PI) was observed. A reduction (p < 0.05) in ADA activity on day 20 PI, as well as an increase (p < 0.05) in ADA activity on days 40 and 60 PI was observed when compared to the control. Based on these results, we can conclude that ATP, ADP and AMP hydrolysis and adenosine deamination were altered in platelets of cattle infected by F. hepatica. Considering the importance of the purinergic system in hemostasis, it is believed that those changes may contribute to the coagulation impairment observed in acute fasciolosis described in the literature.

Oxidative stress and changes in adenosine deaminase activity of cattle experimentally infected by Fasciola hepatica.

The aim of this study was to evaluate the oxidative stress in serum and liver and adenosine deaminase (ADA) activity of cattle experimentally infected by Fasciola hepatica. The group A consisted of five healthy animals (uninfected), and the group B was composed of five animals orally infected with 200 metacercariae of F. hepatica. On days 20, 40, 60 and 80 post-infection (PI) serum was collected to measure oxidative stress variables. On day 100 PI, animals were humanely euthanized and liver samples were collected. Infected animals showed lower (P < 0·05) seric ADA activities on days 40 and 60 PI but higher (P < 0·05) in the liver tissue compared with uninfected animals. Seric and hepatic reactive oxygen species (ROS) were higher (P < 0·05) in infected compared with uninfected animals. Hepatic thiobarbituric acid reactive substances were higher (P < 0·05) in infected animals. Catalase and glutathione S-transferase activities were lower in liver tissue of infected animals, while glutathione peroxidase was higher compared with uninfected (P < 0·05). In summary, we conclude that oxidative stress occurs in cattle experimentally infected by F. hepatica, mainly due to excessive ROS production in the course of fasciolosis, contributing to hepatic damage, and that increased in hepatic ADA activity may contribute to the inflammatory process.

Metastatic mammary carcinoma in a cow / Carcinoma metastático mamário em uma vaca

ABSTRACT: Mammary gland neoplasms in cattle are rarely observed in the field veterinary diagnostics routine. Therefore, the objective of this study is to report a metastatic mammary carcinoma in a fourteen-year-old Holstein cow in the state of Santa Catarina, Brazil. The animal was diagnosed by the field veterinarian with clinical mastitis that was unresponsive to treatment, and was euthanized due to the poor prognosis. At the necropsy, multiple yellow, firm, and sometimes friable nodules, ranging from 0.1 to 20cm were observed in all mammary glands, lymph nodes, kidneys, spleen, liver, pancreas, mediastinal lymph nodes, heart, and lungs. The final diagnosis of mammary carcinoma was established through the association of clinical, necropsy, histopathological, and immunohistochemical findings. Differential diagnoses included diseases such as bovine tuberculosis and chronic fungal or bacterial mastitis.

RESUMO: Carcinomas de glândula mamária em bovinos raramente são vistos na rotina de diagnóstico no campo. Portanto, o objetivo do trabalho é relatar a ocorrência de um carcinoma de mama metastático em uma fêmea bovina de 14 anos, holandesa, no estado de Santa Catarina, Brasil. O animal foi diagnosticado pelo veterinário com mastite irresponsiva a tratamento clínico, e foi eutanasiada devido ao prognóstico desfavorável. Na necropsia foram observados múltiplos nódulos amarelados, firmes, e por vezes friáveis, variando entre 0.1 e 20cm, disseminados em todas as glândulas mamárias, linfonodos, rins, baço, fígado, pâncreas, coração e pulmão. O diagnóstico de carcinoma de glândula mamária foi baseado em achados clínicos, macroscópicos, histopatológicos e de imuno-histoquímica. Os diagnósticos diferenciais incluíram doenças como tuberculose bovina, mastites crônicas de origem bacteriana ou fúngica.

NTPDase and 5'-nucleotidase as inflammatory markers in cattle naturally infected by Eurytrema coelomaticum.

The aim of this study was to evaluate seric NTPDase and 5'nucleotidase activities of cattle naturally infected by Eurytrema coelomanticum, as well as to correlate them to histopathological lesions in the pancreas and the degree of parasitism. Blood samples and pancreas of 51 bovines were collected on a slaughterhouse in Southern Brazil: 33 from cattle naturally infected by E. coelomanticum (the Group A), and 18 from uninfected animals (the Group B). Infected animals showed an average of 532 parasites per pancreas. In the pancreatic histology, ducts displayed hyperplasia, stenosis, proliferation of fibrous tissue, and interstitial inflammatory infiltration of lymphocytes. The serum from infected animals showed an increase in NTPDase activity when ATP was used as substrate (P<0.001). For the ADP substrate, there was no difference between groups regarding NTPDase activity (P=0.37), as well as 5'-nucleotidase activity (P=0.27). Correlating NTPDase activity (ATP substrate) with the degree of histopathological lesions (rho=0.66, P<0.001) and the parasitic load on the pancreas (rho=0.65, P<0.001), a positive correlation was observed. Similar results were found between the degree of histopathological lesions and NTPDase activity (ADP substrate; rho=0.29, P=0.03), and 5'nucleotidase activity (rho=0.35, P=0.01). Based on the results of NTPDase and 5'nucleotidase enzymes in cattle naturally infected by E. coleomanticum, it is possible to suggest that these enzymes are involved in the modulation of inflammation, and they can act as markers of inflammatory response.

Relation between iron metabolism and antioxidants enzymes and δ-ALA-D activity in rats experimentally infected by Fasciola hepatica.

The aim of this study was to evaluate the iron metabolism in serum, as well as antioxidant enzymes, in addition to the Delta-Aminolevulinic Acid Dehydratase (δ-ALA-D) activity in the liver of rats experimentally infected by Fasciola hepatica. Thirty male adult rats (Wistar) specific pathogen free were divided into four groups: two uninfected group (CTRL 1 and CTRL 2) with five animals each and two infected groups (INF 1 and INF 2) with 10 animals each. Infection was performed orally with 20 metacercariae at day 1. On day 15 (CTRL 1 and INF 1 groups) and 87 PI (CTRL 2 and INF 2 groups) blood and bone marrow were collected and the animals were subsequently euthanized for liver sampling. Blood was allocated in tubes without anticoagulant for serum acquisition to measure iron, transferrin and unsaturated iron binding capacity (UIBC). δ-ALA-D, superoxide dismutase (SOD), and catalase (CAT) activities were measured in the liver. A decrease in iron, transferrin and UIBC levels was observed in all infected animals compared to control groups (P < 0.05). Furthermore, iron accumulation was observed in bone marrow of infected mice. Infected animals showed an increase in δ-ALA-D activity at 87 post-infection (PI) (INF 2) as well as in SOD activity at days 15 (INF 1) and 87 PI (INF 2). On the other hand, CAT activity was reduced in rats infected by F. hepatica during acute and chronic phase of fasciolosis (INF 1 and INF 2 groups), when moderate (acute) and severe necrosis in the liver histopathology were observed. These results may suggest that oxidative damage to tissues along with antioxidant mechanisms might have taken part in fasciolosis pathogenesis and are also involved in iron deficiency associated to changes in δ-ALA-D activity during chronic phase of disease.

Hepatic and seric levels of purines in rats experimentally infected by Fasciola hepatica.

The aim of this study was to evaluate hepatic and seric levels of purines, as well as their breakdown products in rats infected by Fasciola hepatica on days 15 and 87 post-infection (PI). Rats were divided into two groups: uninfected (n = 10) and infected (n = 20). On day 15 (n = 5 for uninfected group and n = 10 for infected group) and 87 PI (n = 5 for uninfected group and n = 10 for infected group), animals were euthanized for sampling to evaluate levels of purines by high-performance liquid chromatography. In serum, ATP increased (P < 0.05) and ADP decreased (P < 0.05) on days 15 and 87 PI, while AMP increased (P < 0.05) only on day 15 PI. Hypoxanthine levels increased (P < 0.05) on days 15 and 87 PI, while adenosine and xanthine levels decreased and increased (P < 0.05), respectively, on day 87 PI. No difference was observed regarding seric inosine and uric acid (P > 0.05). Hepatic ATP, adenosine, and uric acid levels decreased (P < 0.05) on days 15 and 87 PI. AMP levels decreased (P < 0.05) on day 87 PI, while xanthine levels increased (P < 0.05) on day 15 PI in the liver. Also in the liver, hypoxanthine levels increased (P < 0.05) on day 15 PI and decreased (P < 0.05) on day 87 PI. On the other hand, there was no difference on hepatic ADP and inosine levels (P > 0.05). Therefore, it is possible to conclude that F. hepatica infection can change purine levels, which may be associated with an inflammatory process, and these alterations may influence fasciolosis pathogenesis.