ABSTRACT The objective of this study was to evaluate the clinical biochemistry behavior of Black-Tufted Marmosets (Callithrix penicillatta) submitted to blood collection without sedation and after general anesthesia with anesthetics isoflurane or sevoflurane. Blood collections were performed on (M1) day before anesthesia by physical restraint, and (M2) after anesthesia. There were four groups: Isoflurane (GI) and Sevoflurane (GS) using an anesthetic box. GIM: isoflurane induction with mask for a shorter period. Control group (GP): physical restraint in both moments. Plasma was separated and frozen to measure clinic biochemistry values. Urea was higher at M2 in groups GI and GP. AST was higher in M2 in GI, GS, and GP and only GI showed an increase in CK in M2. Glucose was higher in M1 in the GI, GS, and GP groups and fructosamine was higher in M2 in the GI. Stress caused by physical restraint can cause biochemical changes and these must be considered when interpreting the exams. Both the inhalational anesthetic isoflurane and sevoflurane did not cause clinically significant changes in clinical biochemistry results.

RESUMO O objetivo desse estudo foi avaliar o comportamento da bioquímica clínica de saguis-do-tufo-preto (Callithrix penicillatta) submetidos à coleta sanguínea sem sedação e após anestesia geral, com os anestésicos isoflurano ou sevoflurano. As coletas de sangue foram realizadas: (M1) dia antes da anestesia por contenção física e (M2) após anestesia. Foram definidos quatro grupos: isoflurano (GI) e sevoflurano (GS), utilizando caixa anestésica; GIM: indução com isoflurano com máscara por um período menor; grupo controle (GCF): contenção física em ambos os momentos. O plasma com EDTA foi separado e congelado para realizar dosagem da bioquímica clínica. A ureia foi maior no M2 nos grupos GI e GCF. A AST foi maior no M2 nos GI, GS e GCF e somente o GI apresentou aumento de CK no M2. A glicose foi maior no M1 nos grupos GI, GS e GCF, e a frutosamina foi maior no M2 no GI. O estresse causado pela contenção física pode causar alterações bioquímicas e essas devem ser levadas em consideração na interpretação dos exames. Tanto o anestésico inalatório isoflurano quanto o sevoflurano não causaram alterações clinicamente significantes nos resultados da bioquímica clínica.

RESUMO: O perfil bioquímico e o status de hidratação de equinos em treinamentos ou competições fornecem dados importantes das suas respostas fisiológicas e metabólicas em relação ao tipo específico de exercício em uma modalidade esportiva. No presente estudo, o status hídrico e o perfil fisiológico-bioquímico de equinos foram avaliados durante treinamento de três tambores, em três tempos (T): em repouso, antes do início da atividade física (T0); imediatamente após 10 minutos de aquecimento ao trote seguido de duas corridas na pista de tambor, intervaladas em 10 minutos (T1); e após uma hora de descanso do segundo percurso (T2). Os parâmetros avaliados foram: frequência cardíaca (FC), frequência respiratória (FR), temperatura corporal (BT) e cor da mucosa; o tempo de enchimento capilar (TEC), volume globular ou hematócrito (VG), proteínas plasmáticas totais (TPP), creatinina sérica (Cre) e a ureia (Ure) foram avaliados e utilizados para inferir o estado hídrico dos animais; a osmolaridade plasmática (Osm) também foi mensurada; as concentrações dos eletrólitos sódio (Na), potássio (K), cloreto (Cl), cálcio total (tCa), magnésio total (tMg) e fósforo (P), e das enzimas musculares foram mensurados no soro, e as de glicose (Gli) e lactato (Lac) no plasma. Os dados das variáveis estudadas foram submetidos à ANOVA e ao teste de Tukey a 5% de probabilidade. Após o exercício (T1), a FC, FR, TC, VG, TPP, Gli, Lac, Cre aumentaram. O P também aumentou (P<0,05), mas não alcançou nível de hiperfosfatemia, e o K diminuiu (P<0,05), mas não ao nível de hipocalemia. Embora com médias menores, a FC, FR, TC, VG, K e o Lac não retornaram aos níveis basais (T0) após o repouso (T2), apenas a Gli, enquanto o fósforo diminuiu (P<0,05). A Osm, ureia, Na, Cl, tCa, tMg, CK e AST não variaram entre os tempos (P>0,05). Concluiu-se que, o exercício de intensidade máxima realizado em dois percursos de três tambores causou leve hemoconcentração, não alterou a osmolaridade plasmática nem importantes concentrações de eletrólitos e de enzimas musculares dos equinos, porém, causou hiperlactatemia, sem completa recomposição da concentração do lactato após uma hora de descanso.

ABSTRACT: Studies on biochemical constituents and hydration of horses in training or competitions are essential for the knowledge of their adaptive physiological and metabolic responses to the type of exercise inherent to the sport. The present research evaluated the effects of exercise on hydric status and physiologic and biochemical profiles in Quarter Horses during a barrel race training session. The design consisted of three evaluation times (T): at rest, before the start of physical activity (T0); immediately after a 10-minute warm-up trot and then running the barrel race courses twice with a 10-minute interval (T1); and after one hour’s rest after the second course (T2). The parameters analyzed were: heart rate (HR), respiratory rate (RR), body temperature (BT) and mucose color; the capillary refill time (CRT), packed cell volume (PCV), total plasma proteins (TPP), serum creatinine (CRE) and blood urea nitrogen (BUN) were evaluated and used to infer water status; plasma osmolarity (Osm) was measured; the electrolytes sodium (Na), potassium (K), chloride (Cl), total calcium (tCa), total magnesium (tMg) and phosphorus (P), plasma glucose (Glu) and lactate (Lac) and the muscle enzymes creattine kinase (CK) and aspartate aminotransferase (AST) completed the evaluated parameters. The data for the variables studied were submitted to ANOVA and the Tukey test at 5% probability. After exercise (in T1), HR, RR, BT, PCV, TPP, Glu, Lac, Cre increased (P<0.05), there was also increase in phosphorus and decrease in K (P<0.05), but there was no hypophosphatemia and hipokalemia, respectively. After rest (in T2), only glucose returned to baseline levels (T0) and, with lower mean values, HR, RR, BT, PCV, K and Lac did not return to baseline levels (T0), while P decreased (P<0.05). Osm, BUN, Na, Cl, tCa, tMg, CK and AST did not change between times (P>0.05). It was concluded that the maximum intensity exercise performed on two barrel race courses caused mild hemoconcentration, did not changed plasma osmolality or concentrations of important electrolytes and muscle enzymes of horses, but caused hyperlactatemia without the plasma lactate concentrations being fully recomposed after resting.

Abstract AIMS To evaluate the acute effects of a resistance exercise session performed on ladder on energy metabolism, stress, and muscle damage in rats. METHODS Male Wistar rats were randomly distributed in Exercise (E) (n=30) and Control (C) (n = 20) groups. The E group performed a resistance exercise session on a vertical ladder with weights on their tails. Blood samples were collected at rest and after each climb to analyze lactate levels and ten minutes after the last climb to analyze lactate dehydrogenase (LDH), creatine kinase (CK), and corticosterone levels. RESULTS Blood lactate levels remained stable during exercise. Serum corticosterone, blood glucose, LDH and CK levels increased and glycogen content decreased in the E group, when compared to the C group. CONCLUSION These results suggest that resistance exercise performed on ladder is a model of high-intensity exercise. However, the stabilization of lactate during the session suggests that the aerobic metabolism is an important factor during the intervals between climbs.

Nos últimos anos, o equino atleta vem sendo cada vez mais requerido. Dessa forma, as exigências por alto desempenho têm fomentado o interesse pelo estudo das afecções relacionadas com a fisiopatologia de diversas enfermidades dos equinos. A relação entre o íon magnésio e o exercício físico tem recebido atenção significativa visto que este íon está intimamente relacionado ao tecido muscular estriado esquelético. Além disso, dentre as principais estratégias para a detecção e acompanhamento clínico de lesões musculares, destacam-se a avaliação das atividades das enzimas creatino quinase (CK), lactato desidrogenase (LDH) e aspartato aminotransferase (AST). A busca pelo estabelecimento de parâmetros que se relacionam entre si é um fator determinante na compreensão de alterações fisiológicas encontradas diante do esforço em equinos atletas. Desta forma, o presente trabalho teve como objetivo determinar como as concentrações sanguíneas do íon magnésio e as atividades enzimáticas das enzimas CK, LDH e AST comportaram-se em equinos Puro Sangue Árabe finalistas de provas de enduro de 90km e relacionar as possíveis alterações com o tipo de esforço físico desempenhado pelos animais. Foram avaliadas a atividade enzimática das enzimas CK, LDH, AST e a concentração do íon magnésio no exercício em relação ao repouso de 14 equinos clinicamente hígidos da raça Puro Sangue Árabe, sendo 9 machos e 5 fêmeas, com idades variando entre 6 a 12 anos, submetidos a treinamento para enduro e participantes de provas de 90 km. Pode-se observar que as variáveis acima mencionadas sofreram aumento com diferença estatística em relação ao repouso. O exercício físico de enduro determinou a ocorrência de alterações nas atividades enzimáticas das enzimas CK (p≤0,001), LDH (p=0,0001), AST (p=0,0007) e na concentração do íon magnésio (p=0,0004), no exercício em relação ao repouso (p≤0,05). Fato que determinou alteração de permeabilidade das células musculares estriadas esqueléticas, sugerindo o estabelecimento de um processo inflamatório agudo. Devido à expressão da atividade enzimática da CK (p≤0,001), por sua especificidade em relação à ocorrência de danos na musculatura estriada esquelética, juntamente com o íon magnésio (p=0,0004) que participa de várias reações celulares. Houve alterações na concentração de proteína plasmática total (p=0,0009) e hematócrito (p=0,0001), entre os momentos avaliados. Portanto estes resultados servem como valores de referência de equinos finalistas de provas de enduro de 90 km, auxiliando na prevenção da ocorrência de possíveis danos musculares e processos inflamatórios severos.

In recent years, due to rising competitive demands, the equine athlete is being increasingly required. Thus, the demands for high performance have fostered interest in the study of pathophysiology of various horse diseases. The relationship between magnesium and exercise has received significant attention because this ion is closely related with the skeletal muscle tissue. Moreover, among the main strategies for the detection and monitoring of clinical muscle damage, features the evaluation of the activity of the enzymes creatine kinase (CK), lactate dehydrogenase (LDH) and aspartate aminotransferase (AST). The search for the establishment of parameters that relate to each other is a determining factor in understanding the physiological changes found on athletic horses in effort. Thus, this study aimed to determine how the blood concentrations of magnesium ion and the enzymatic activities of the enzymes CK, LDH and AST behave in Arabian finalist horses in endurance races of 90km and to relate possible changes to the type of physical effort played by animals. It was evaluated the enzymatic activities of the enzymes CK, LDH, AST e the concentration of the ion magnesium in exercise in relation to the rest state of 14 clinically healthy Arabian horses, 9 males and 5 females, with ages ranging from 6 to 12 years, undergoing endurance training and participants in 90 km distance rides. All variables evaluated had an increase with statistical differences in relation to rest. The physical endurance exercise determined the occurrence of changes in enzyme activities of CK (p≤0.001), LDH (p=0.0001), AST (p=0.0007) and in the concentration of magnesium ion (p=0.0004), in exercise in relation to rest (p≤0.05). Fact that determined changes in permeability of striated skeletal muscle cells, suggesting the establishment of an acute inflammatory process. Mainly due to the expression of enzymatic activity of CK (p≤0.001), for its specificity in relation to the damage to skeletal striated muscles, along with the magnesium ion (p=0.0004) that actively acts in various cellular reactions. There were changes in total plasma protein concentrations (p=0.0009) and hematocrit (p=0.0001), between the evaluated moments. Therefore, these results serve as a reference of support equine finalists in an endurance race of 90 km, aiding in the prevention of the occurrence muscle damage and severe inflammatory processes.

Because an enriched environment (EE) enhances T-cell activity and T-lymphocytes contribute to immunopathogenesis during heterologous dengue virus (DENV) infections, we hypothesised that an EE increases dengue severity. To compare single serotype (SS) and antibody-enhanced disease (AED) infections regimens, serial intraperitoneal were performed with DENV3 (genotype III) infected brain homogenate or anti-DENV2 hyperimmune serum followed 24 h later by DENV3 (genotype III) infected brain homogenate. Compared AED for which significant differences were detected between the EE and impoverished environmental (IE) groups (Kaplan-Meyer log-rank test, p = 0.0025), no significant differences were detected between the SS experimental groups (Kaplan-Meyer log-rank test, p = 0.089). Survival curves from EE and IE animals infected with the AED regimen were extended after corticoid injection and this effect was greater in the EE than in the IE group (Kaplan-Meyer log-rank test, p = 0.0162). Under the AED regimen the EE group showed more intense clinical signs than the IE group. Dyspnoea, tremor, hunched posture, ruffled fur, immobility, pre-terminal paralysis, shock and death were associated with dominant T-lymphocytic hyperplasia and presence of viral antigens in the liver and lungs. We propose that the increased expansion of these memory T-cells and serotype cross-reactive antibodies facilitates the infection of these cells by DENV and that these events correlate with disease severity in an EE.

INTRODUÇÃO: A doença de Chagas é uma infecção causada pelo Trypanosoma cruzi que afeta oito milhões de pessoas na América Latina. Um fator ligado ao estilo de vida que interfere significativamente na resposta à infecção é o exercício físico, dependendo do tipo, intensidade e frequência da atividade praticada. OBJETIVO: Avaliar a influência do exercício físico aeróbio moderado crônico pré-infecção na evolução da infecção experimental pelo T. cruzi em camundongos de duas linhagens distintas pertencentes aos dois sexos. MÉTODOS: Camundongos Swiss e BALB/c (machos e fêmeas) com 30 dias de idade foram divididos em quatro grupos para cada linhagem e sexo (total de 16) e nomeados como segue: SM (Swiss machos), SF (Swiss fêmeas), BM (BALB/c machos) e BF (BALB/c fêmeas). Os grupos foram: NT+NI (não treinado+não infectado), T+NI (treinado+não infectado), NT+I (não treinado+infectado) e T+I (treinado+infectado). O programa de exercício físico aeróbio moderado crônico pré-infecção foi realizado durante oito semanas, com uma sessão diária de treinamento, cinco vezes na semana. O inóculo foi de 1.400 tripomastígotas sanguíneos da cepa Y do T. cruzi, via intraperitoneal. Foi avaliado o pico de parasitos, parasitemia total média e as medidas das atividades séricas de CK e CK-MB. RESULTADOS E CONCLUSÃO: O treinamento físico promoveu nas duas linhagens e em ambos os sexos redução no pico de parasitos e na parasitemia total média em animais infectados pelo T. cruzi. O treinamento físico promoveu redução nas atividades séricas de CK e CK-MB em animais infectados pelo T. cruzi, de ambos os sexos, das duas linhagens, exceto para fêmeas Swiss na atividade de CK e CK-MB.

BACKGROUND: Chagas disease is an infection caused by Trypanosoma cruzi that affects eight million people in Latin America. One factor linked to the lifestyle that significantly interferes in the response to infection is physical exercise, depending on the kind, intensity and frequency of the activity practiced. OBJECTIVE: To evaluate the influence of pre-infection chronic moderate aerobic exercise in the development of experimental infection with T. cruzi in mice of two distinct lineages from both sexes. METHODS: 30-day old Swiss and BALB/c mice (male and female) were divided into four groups for each strain and sex (total 16) and named as follows: SM (Swiss males), SF (Swiss females) BM (BALB/c mice) and BF (BALB/c mice). The groups were: NT NI (untrained uninfected) T NI (trained not infected); NT I (untrained infected), TI (trained infected). The aerobic exercise pre-moderate chronic infection training was performed with one daily session for eight weeks, five times a week. The inoculum was 1,400 blood trypomastigotes of Y strain of T. cruzi intraperitoneally. The peak of parasites, parasitemia total and average measurements of the serum activities of CK and CK-MB were evaluated. RESULTS AND CONCLUSIONS: The physical training promoted reduction in peak, parasitemia parasites and total average in animals infected with T. cruzi in both strains and sexes. Physical training induced reduction in serum activities of CK and CK-MB in animals infected with T. cruzi of both sexes and from the two strains, except for females in the Swiss CK activity.

A nanopartícula de prata (AgN) é um dos mais proeminentes nanoprodutos, uma vez que a prata exibe propriedades físicas, químicas e biológicas notavelmente incomuns. Creatina quinase (CK) desempenha um papel central no metabolismo de tecidos que consomem muita energia, tais como o cérebro, músculo esquelético e coração, funcionando como um efetivo sistema tampão dos níveis de ATP celular. Uma diminuição na atividade da CK pode alterar a homeostase energética, contribuindo para a morte celular. No presente trabalho nós estudamos o efeito in vitro de AgN na atividade da CK de cérebro, coração e músculo esquelético de ratos. Nossos resultados demonstraram que AgN (10, 25 e 50 mg L-1) in vitro inibiram a atividade da CK em cérebro e músculo esquelético, porém não em coração. Vários trabalhos mostraram que os efeitos citotóxicos da AgN provavelmente envolvem a interação entre íons prata e grupos sulfidrila de proteínas. Nós sugerimos que a AgN inibiu a atividade da CK por meio da interação com grupos tiol da enzima.

One of the most prominent nanoproducts is the silver nanoparticle (AgN), since silver ions exhibit remarkably unusual physical, chemical and biological properties. Creatine kinase (CK) plays a central role in metabolism of high-energy consuming tissues such as brain, skeletal muscle and heart, where it functions as an effective buffering system of cellular ATP levels. A decrease of CK activity may impair energy homeostasis, contributing to cell death. In the present work we studied the in vitro effect of AgN on the activity of CK from rat brain, heart and skeletal muscle. Our results demonstrated that AgN (10, 25 and 50 mg L-1) in vitro inhibited CK from brain and skeletal muscle, but not from heart. Several works showed that AgN cytotoxic effects probably involve interaction between silver ions and sulphydryl groups of proteins. We suggest that AgN inhibited CK activity through interactions with thiol groups of the enzyme.

ALT-C, an ECD motif (glutamic acid, cysteine, aspartic acid) disintegrin from Bothrops alternatus snake venom, induces α2β1 integrin-mediated signaling and neutrophil chemotaxis. In vitro, in human umbilical vein endothelial cells (HUVEC), ALT-C induces cell proliferation, thus showing an interesting potential for tissue regeneration studies. This work aimed to evaluate the influence of ALT-C in myoblast viability and differentiation. Myoblasts were obtained from hind limb muscles of 3 to 4-day old Wistar rats. The cells were incubated with ALT-C at different concentrations and incubation periods were followed by total RNA isolation. cDNA synthesis and real time polymerase chain reaction (PCR) were performed with primers of myoD as well as of both (slow and fast) myosin heavy chain isoforms (MHC). ECD-disintegrin increased myoblast viability in a dose-dependent way, mostly with 50 to 100 nM concentrations, and such effect was more prevalent after 48 hours. No changes in gene expression of both MHC isoforms were observed in ALT-C-treated cells. MyoD expression was not detected, which suggests that myoblasts were in mature stages. Protease activity and cytokine array tested in a medium of 50 nM ALT-C-treated cells after 48 hours were not different from controls. In conclusion, it was shown that myoblats are sensitive to ALT-C indicating an integrin-mediated intracellular signaling that increases cell viability.

We investigated the protective effect of suramin, an enzyme inhibitor and an uncoupler of G protein from receptors, on the myotoxic activity in mice of different crotalid snake venoms (A.c. laticinctus, C.v. viridis, C.d. terrificus, B. jararacussu, B. moojeni, B. alternatus, B. jararaca, L. muta). Myotoxicity was evaluated in vivo by injecting im the venoms (0.5 or 1.0 mg/kg) dissolved in physiological saline solution (0.1 ml) and measuring plasma creatine kinase (CK) activity. Two experimental approaches were used in mice (N = 5 for each group). In protocol A, 1 mg of each venom was incubated with 1.0 mg suramin (15 min, 37ºC, in vitro), and then injected im into the mice at a dose of 1.0 mg/kg (in vivo). In protocol B, venoms, 1.0 mg/kg, were injected im 15 min prior to suramin (1.0 mg/kg, iv). Before and 2 h after the im injection blood was collected by orbital puncture. Plasma was separated and stored at 4ºC for determination of CK activity using a diagnostic kit from Sigma. Preincubation of some venoms (C.v. viridis, A.c. laticinctus, C.d. terrificus and B. jararacussu) with suramin reduced (37-76%) the increase in plasma CK, except for B. alternatus, B. jararaca or L. muta venoms. Injection of suramin after the venom partially protected (34-51%) against the myotoxicity of B. jararacussu, A.c. laticinctus and C.d. terrificus venom, and did not protect against C.v. viridis, L. muta, B. moojeni, B. alternatus or B. jararaca venoms. These results show that suramin has an antimyotoxic effect against some, but not all the North and South American crotalid snake venoms studied here.