Cardioprotective Effects of the 4-Week Aerobic Running Exercises Before Treatment with Doxorubicin in Rats

Doxorubicin is associated with cardiotoxicity, and physical exercise seeks to minimize the toxic effects of doxorubicin through physiological cardiac remodeling, as well as the reduction of oxidative stress, evidenced by previous studies. This study aimed to analyze whether running training before treatment with doxorubicin influences tolerance to physical exertion and cardiotoxicity. Thirty-nine male Wistar rats, aged 90 days and weighing between 250 and 300 g, were divided into 4 groups: Control (C), Doxorubicin (D), Trained (T), and Trained + Doxorubicin (TD). Animals in groups T and DT were submitted to treadmill running for 3 weeks, 5 times a week at 18 m/min for 20-30 min before treatment with doxorubicin. Animals in groups D and DT received intraperitoneal injections of doxorubicin hydrochloride three times a week for two weeks, reaching a total cumulative dose of 7.50 mg/kg. Our results show an increase in total collagen fibers in the D group (p = 0.01), but no increase in the TD group, in addition to the attenuation of the number of cardiac mast cells in the animals in the TD group (p = 0.05). The animals in the TD group showed maintenance of tolerance to exertion compared to group D. Therefore, running training attenuated the cardiac damage caused by the treatment with doxorubicin, in addition to maintaining the tolerance to exertion in the rats.

Systemic alterations induced by phospholipase A2 , BmooTX-I, isolated from Bothrops moojeni snake venom

Ophidic accidents are among the problems of public health in Brazil. The components from bothropic venom are responsible for many systemic clinical complications resulting from envenomation. The present work aimed to analyse the systemic changes induced in mice after intraperitoneal administration of BmooTX-I, a myotoxic acidic phospholipase A₂ isolated from Bothrops moojeni venom. Urinalysis was performed and the following plasma biochemical markers were documented: urea, creatinine and uric acid (renal function); glucose and amylase (pancreatic function); alanine aminotransferase, alkaline phosphatase and gamma-GT (intra- and extrahepatic function); creatine kinase and enzymatic lactate (muscle function). Our results showed that after the intraperitoneal injection of BmooTX-I the urine of these animals showed glycosuria, proteinuria, haematuria, bacteriuria, bilirubinuria, polyuria and nitrite. The plasma biochemical analysis showed alterations in levels of urea, creatinine and uric acid. Amylase concentration was not altered significantly, but the plasma glucose increased significantly compared to controls. The plasma levels of alanine aminotransferase and alkaline phosphatase decreased and increased, respectively, in these same animals. On the other hand, the plasma γGT concentration did not undergo significant modification compared to the control group. The plasma concentration of CK increased, while the enzymatic lactate concentration decreased after the injection of the BmooTX-I. Therefore, in mice BmooTX-I is capable of causing systemic alterations which manifest as renal, muscular, hepatic and pancreatic impairment.

Influence of the use of testosterone associated with physical training on some hematologic and physical parameters in older rats with alloxan-induced diabetes

OBJECTIVE

This study investigated the possible blood changes in wistar rats elderly with and without treatment with anabolic steroids submitted physical training.

MATERIALS AND METHODS

Elderly rats (32) were divided into four groups: normal (N), treated normal (NT), diabetic (D) and treated diabetic (DT). They were submitted to 20 sessions of swimming with overload (5% body weight), 40 min/day for four weeks. The NT and DT groups received application of testosterone twice a week. At the end of the sessions, the animals were subjected to swimming until exhaustion and then killed for removal of blood and visceral fat. We evaluated maximum swim time, weight of visceral fat, erythrogram, leukogram, lipidogram and serum levels of glucose, lactate, aspartate aminotransferase and creatine kinase. The results were compared using one-way ANOVA followed by the post hoc Tukey test.

RESULTS

In elderly diabetic rats, the use of anabolic associated with physical training in older rats resulted in improvement in erythrogram, lipidogram and physical performance for high-intensity aerobic exercise. However, it was related to changes in leukocyte count, probably associated with inflammation.

CONCLUSION

The combination of the use of testosterone with physical training, followed by maximal effort test caused changes hematological and biochemical can be associated with improvement in physiological characteristics, with increase of the swimming time and decrease of visceral fat levels, improvement in aerobic metabolism of fatty acids and glucose in normal and diabetic animals.

Hematology, biochemical profile and thyroid hormones of four species of freshwater stingrays of the genus Potamotrygon

<p>Potamotrygonidae e um grupo de raias endêmicas da América do Sul distribuídas nas principais bacias hidrográficas brasileiras, mas informações sobre suas variáveis hematológicas e bioquímicas são escassas. Este estudo teve como objetivo determinar estas variáveis em <em>Potamotrygon motoro </em>e <em>P. falkneri </em>na Bacia do Rio Paraná, Estado do Paraná e de <em>P. orbignyi </em>e <em>P. scobina </em>do Rio Piririm, na Bacia Amazônica, Estado do Amapá. Foi capturado um total de 53 espécimes de <em>Potamotrygon </em>spp. para colheita de sangue e avaliações do hemograma e variáveis bioquímicas séricas. Os valores do hemograma foram próximos para as quatro espécies e os resultados com diferenças significativas entre <em>Potamotrygon falkneri</em>, <em>P. motoro, P. orbigni </em>e <em>P. scobina </em>ocorreram quanto ao número de eritrócitos e heterófilos. Apesar da diversidade geográfica os resultados apresentaram pouca interferência dos diferentes habitats nas variáveis avaliadas. Os níveis de proteínas, globulinas, relação albumina:globulina, acido úrico, creatinina, ureia, HDL-C, relação cálcio:fósforo, sódio, cloreto, AST, ALT, creatinoquinase (CK), fosfatase alcalina, hormônios triiodotironina (T3) e tiroxina (T4) não diferiram entre as espécies de Potamotrygon. Porem, os níveis de albumina, glicose, colesterol total, triglicerídeos e gama glutamil transferase (GGT) apresentaram diferenças. Este fato sugere pouca interferência do habitat nas variáveis avaliadas apesar da diversidade geográfica de origem das raias de vida livre.</p>

Comparison of moulting methods for layers: high-zinc diet versus fasting

The serum biochemical profiles, thyroid hormones, body weights and the production and quality of eggs subsequent to moulting, were compared in laying hens subjected to conventional forced moulting or forced moulting with a diet high in zinc. A total of 200 Dekalb White laying hens in their second production cycle were studied. Blood sampling was conducted in a factorial experimental design (2 × 3) with two methods of moulting (fasting or zinc) and three sampling periods (pre-moult, moult and subsequent peak). Total egg protein content, including globulins, was greater with the zinc diet, whereas egg weight and albumen percentage were greater after fasting. The zinc method resulted in an increased shell thickness and calcium percentage but lower percentage of phosphorus. During the moulting period, the hens in the zinc group had heavier mean body weights. It was concluded that moulting with a high-zinc diet could replace fasting, without negative effects on body weight, biochemical variables or subsequent egg quality and production. The zinc method was also better for the birds' welfare.

Plasma rico em plaquetas autólogas na cicatrização do tendão do músculo gastrocnêmio de coelhos

<p>As lesões tendíneas podem envolver a secção parcial ou total do tendão calcâneo comum e ocasionar alterações posturais do membro locomotor. O presente trabalho avaliou o efeito da aplicação tópica de concentrado de plaquetas autólogas na reparação do tendão do musculo gastrocnêmio de coelhos, decorridos 45 e 90 dias de período pós-operatório (PO). Doze coelhos adultos foram separados em dois grupos (n = 6) e submetidos a punção cardíaca e colheita de 10 mL de sangue para obtenção do plasma rico em plaquetas (PRP). Nos animais de ambos os grupos, foi realizada a tenotomia transversal total no terço médio do ventre lateral do tendão do musculo gastrocnemio e a sua aproximação com a sutura de Kessler modificada e fio de nailon. Nos animais do grupo tratado, foi aplicado sobre a síntese dos tendões em media 490.644 mil plaquetas/μL do PRP e notou-se maior quantidade de fibras colágenas em relação ao controle, sendo que aos 90 dias de PO a intensidade de colágeno observado foi maior que nos animais com 45 dias, com maior quantidade de fibroblastos nos controles em relação aos tratados. A administração de concentrado de plasma de plaquetas autógenas no reparo do tendão gastrocnemio de coelhos estimula e organiza o processo de reparação e ocasiona produção precoce de fibras colágenas.</p>

Prevalence and molecular characterization of Hepatozoon canis in dogs from urban and rural areas in Southeast Brazil

The objective of this survey was to investigate the prevalence of Hepatozoon infection in dogs in the rural and urban areas of Uberlândia, Brazil by PCR and molecular characterization. DNA was obtained from blood samples collected from 346 local dogs from both genders and various ages. Seventeen PCR products from positive blood samples of urban dogs and 13 from the rural dogs were sequenced. Partial sequences of the 18S rRNA gene indicated that all 30 dogs were infected with Hepatozoon canis similar in sequence to H. canis from southern Europe. Four local dog sequences were submitted to GenBank (accessions JN835188; KF692038; KF692039; KF692040). This study indicates that H. canis is the cause of canine hepatozoonosis in Uberlândia and that infection is similarly widespread in rural and urban dogs.

Infection of dogs by experimental inoculation with human isolates of Giardia duodenalis: clinical and laboratory manifestations

The susceptibility of dogs to experimental inoculation with trophozoites and cysts of human isolates of Giardia duodenalis and the clinical and laboratory profiles of infection of these animals were studied. Two groups (A and B), each comprising three dogs, were inoculated with G. duodenalis trophozoites and cysts, respectively. A third group of two dogs was not inoculated and remained as control. After inoculation feces were collected daily to determine the pre-patent period, by flotation in 33% zinc sulfate solution. Blood samples (5 mL) were collected from animals at 15-day intervals during the 165 days of the experimental period and were used to carry out the hemogram and biochemical evaluation of the levels of total protein, albumin, alanine aminotransferase, gamma glutamyltransferase, urea and creatinine. A prepatent period was observed at 5–6 days post-inoculation (p.i.) in the inoculated dogs, with cysts eliminated for approximately 3 months. No alterations were seen in the clinical parameters evaluated. Anemia was observed at 15 p.i. in the inoculated dogs. The mean eosinophil count of inoculated groups was higher than that of the control (p ≤ 0.05) but none of the biochemical parameters analyzed presented significant differences. The results of this study show that G. duodenalis from human isolates is able to infect dogs with minimal systemic manifestations without producing clinical signs of giardiasis.