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1.
Einstein (Sao Paulo) ; 18: eAO4784, 2020.
Artigo em Inglês, Português | MEDLINE | ID: mdl-31553356

RESUMO

OBJECTIVE: To evaluate the effect of three types of muscular resistance training on adiposity, inflammation levels and insulin activity in Swiss mice with fat-rich diet-induced obesity. METHODS: Lean and obese male Swiss mice were selected and allocated to one of eight groups comprising eight mice each, as follows: standard diet + no training; standard diet + muscular resistance training; standard diet + hypertrophy training; standard diet + strength training; high-fat diet + no training; high-fat diet + muscular resistance training; high-fat diet + hypertrophy training; high-fat diet + strength training. The training protocol consisted of stair climbing for a 10-week period. Blood samples were collected for lactate analysis, glucose level measurement and insulin tolerance test. After euthanasia, adipose tissues were removed and weighed for adiposity index determination. Fragments of epididymal adipose tissue were then embedded for histological analysis or homogenized for tumor necrosis factor alpha level determination using the ELISA method. RESULTS: Ausency of differences in total training volume and blood lactate levels overall emphasize the similarity between the different resistance training protocols. Body weight loss, reduced adipocyte area and lower adiposity index were observed in trained obese mice, regardless of training modality. Different training protocols also improved insulin sensitivity and reduced inflammation levels. CONCLUSION: Resistance training protocols were equally effective in reducing body fat, inflammation levels and insulin resistance in obese mice.


Assuntos
Adiposidade/fisiologia , Hipertrofia/fisiopatologia , Inflamação/fisiopatologia , Resistência à Insulina/fisiologia , Exercícios de Alongamento Muscular/métodos , Obesidade/fisiopatologia , Condicionamento Físico Animal/fisiologia , Tecido Adiposo Branco/fisiopatologia , Animais , Glicemia/análise , Peso Corporal/fisiologia , Dieta Hiperlipídica , Ensaio de Imunoadsorção Enzimática , Masculino , Camundongos , Camundongos Obesos , Reprodutibilidade dos Testes , Treinamento de Resistência/métodos , Fatores de Tempo , Fator de Necrose Tumoral alfa/análise
2.
An Acad Bras Cienc ; 91(4): e20180957, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31800698

RESUMO

The mechanism behind exercise-induced fatigue is a significant topic in the field of sports physiology. Therefore, establishing and evaluating an acute exercise-induced fatigue animal model that explores the limits of the motor system may provide greater insight into these mechanisms. Heart rate is an important quantitative parameter that accurately reflects the immediate change in physical function due to exercise load. And there is likely to be an important correlation between heart rate and behavioral performance. In this study, changes in heart rate and behavioral indexes during exercise-induced fatigue were quantitatively analyzed in rats using heart rate telemetry and video methods respectively. The behavioral indexes were used as independent variables and the degree of fatigue was used as the forecast value. Ternary quadratic function curve fitting was used to deduce a formula to calculate a fatigue score: Y = 15.2548+0.4346∙xa-0.1154∙xb+0.6826∙xc+0.0044∙xa∙xb-0.0021∙xb∙xc-0.0013∙xc∙xa-0.0023∙xa2-0.0016∙xb2 (r2=0.906). It identified a linear relationship between heart rate and exercise intensity, with a plateau in heart rate occurring during difference periods. It will serve as an effective reference for the modeling of exercise-induced fatigue. In addition, it also provides a theoretical method for analyzing the correlation between peripheral and central parameters.


Assuntos
Teste de Esforço , Fadiga , Condicionamento Físico Animal/fisiologia , Resistência Física/fisiologia , Animais , Masculino , Modelos Animais , Ratos , Ratos Wistar , Fatores de Tempo
3.
Braz J Med Biol Res ; 52(12): e8576, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31800730

RESUMO

Physical exercise is a known preventive and therapeutic alternative for several cerebrovascular diseases. Therefore, the objective of the present study was to evaluate the motor performance and histomorphometry of the biceps brachii, soleus, and tibialis anterior muscles of rats submitted to a treadmill training program prior to the induction of cerebral ischemia via occlusion of the middle cerebral artery (OMCA). A total of 24 Wistar rats were distributed into four groups: Sham-Sed: sedentary control animals (n=6), who underwent sham surgery (in which OMCA did not occur); Sham+Ex: control animals exercised before the sham surgery (n=6); I-Sed: sedentary animals with cerebral ischemia (n=6); and I+Ex: animals exercised before the induction of ischemia (n=6). The physical exercise consisted of treadmill training for five weeks, 30 min/day (5 days/week), at a speed of 14 m/min. The results showed that the type-I fibers presented greater fiber area in the exercised ischemic group (I+Ex: 2347.96±202.77 µm2) compared to the other groups (Sham-Sed: 1676.46±132.21 µm2; Sham+Ex: 1647.63±191.09 µm2; I+Ex: 1566.93±185.09 µm2; P=0.0002). Our findings suggested that the angiogenesis process may have influenced muscle recovery and reduced muscle atrophy of type-I fibers in the animals that exercised before cerebral ischemia.


Assuntos
Isquemia Encefálica/complicações , Infarto da Artéria Cerebral Média , Músculo Esquelético/fisiopatologia , Atrofia Muscular/prevenção & controle , Condicionamento Físico Animal/fisiologia , Animais , Isquemia Encefálica/fisiopatologia , Modelos Animais de Doenças , Masculino , Atrofia Muscular/etiologia , Atrofia Muscular/patologia , Ratos , Ratos Wistar
4.
J Int Soc Sports Nutr ; 16(1): 60, 2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31829236

RESUMO

BACKGROUND: Ursolic acid altered muscle protein metabolism in normal and resting conditions after acute resistance exercise, suggesting that eating fruits rich in ursolic acid could enhance muscle protein synthesis and decrease muscle degradation. Aronia melanocarpa, a member of the family Rosaceae and native to North America and Eastern Canada, is rich in ursolic acid. In this study, we examined the effects of A. melanocarpa extract (AME) supplementation on the mTORC1 signaling pathway and muscle degradation-related factors in rats, both alone and in combination with resistance exercise. METHODS: Male Sprague-Dawley rats were divided into AME and normal chow (NOR) groups. AME group was fed chow providing a dose of 3 g/kg of AME and 115 mg/kg of ursolic acid for 7 days, whereas NOR rats were fed normal powder chow. The right gastrocnemius muscle of each animal was isometrically exercised (5 sets of ten 3-s contractions, with a 7-s interval between contractions and 3-min rest intervals between sets), while the left gastrocnemius muscle served as an internal control. Western blotting and real-time polymerase chain reaction were used to assess expression of factors involved in the mTORC1 signaling pathway and muscle degradation. RESULTS: At 1 h after resistance exercise, phosphorylation of ERK1/2 was significantly increased by AME consumption. At 6 h after resistance exercise, AME consumption significantly increased the phosphorylation of Akt, p70S6K, rpS6, and AMPK. It also increased MAFbx expression. Furthermore, AME significantly increased the phosphorylation of p70S6K and rpS6 in response to resistance exercise. However, AME did not increase muscle protein synthesis (MPS) after resistance exercise. AME did not affect the expression of any of the mediators of protein degradation, with the exception of MAFbx. CONCLUSIONS: Dietary AME enhanced mTORC1 activation in response to resistance exercise without increasing MPS. Moreover, it neither accelerated muscle protein degradation nor otherwise negatively affected protein metabolism. Further study is needed to clarify the effect of the combination of AME and chronic resistance training on muscle hypertrophy.


Assuntos
Alvo Mecanístico do Complexo 1 de Rapamicina/fisiologia , Músculo Esquelético/efeitos dos fármacos , Condicionamento Físico Animal/fisiologia , Extratos Vegetais/farmacologia , Transdução de Sinais , Triterpenos/farmacologia , Animais , Dieta , Masculino , Músculo Esquelético/fisiologia , Photinia/química , Biossíntese de Proteínas , Ratos Sprague-Dawley
5.
Adv Neurobiol ; 23: 209-267, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31667811

RESUMO

Most glycogen in cerebral cortex is located in astrocytes, and the importance of glycogenolysis for critical functions, including neurotransmission and memory consolidation, is strongly supported by many studies. However, specific mechanisms through which glycogen sustains essential functions remain to be established by rigorous, quantitative studies. Cerebral cortical glycogen concentrations are in the range of 10-12 µmol/g in carefully-handled animals, and the calculated rate of glycogenolysis (CMRglycogen) during sensory stimulation is approximately 60% that of glucose utilization (CMRglc) by all cells, with lower rates during acute hypoglycemia and exercise to exhaustion. CMRglycogen is at least fourfold higher when the volume fraction of astrocytes is taken into account. Inclusion of glycogen consumed during sensory stimulation in calculation of the oxygen-glucose index (OGI = CMRO2/CMRglc, which has a theoretical maximum of 6 when no other substrates are metabolized) reduces OGI from 5.0 to 2.8. Thus, at least 53% of the carbohydrate is not oxidized, suggesting that glycogen mobilization supports astrocytic glycolysis, not neuronal oxidation of glycogen-derived lactate that would cause OGI to exceed 6. Failure of glycogenolysis to dilute the specific activity of lactate formed from blood-borne [6-14C]glucose indicates compartmentation of glycolytic metabolism of glucose and glycogen and the rapid release from cerebral cortex of glycogen-derived lactate. Together, these findings invalidate the conclusion by others that glycogen-derived lactate is a major fuel for neurons during neurotransmission, memory consolidation, and exercise to exhaustion. Alternative mechanisms, including glucose sparing for neurons, are presented as testable explanations for data interpreted as lactate shuttling.


Assuntos
Astrócitos/metabolismo , Córtex Cerebral/metabolismo , Metabolismo Energético , Glicogenólise , Glicólise , Hipoglicemia/metabolismo , Neurônios/metabolismo , Condicionamento Físico Animal/fisiologia , Animais , Córtex Cerebral/citologia
6.
Can J Vet Res ; 83(4): 272-278, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31571727

RESUMO

High-intensity exercise can be associated with the occurrence of muscle injury, as well as the induction of an acute-phase response (APR). The present study aims to investigate the synthesis and profile of serum proteins in horses before and after participating in 2 different exercise protocols and to relate this profile to the presence or absence of muscular injury caused by exercise. Ten purebred Arabian (n = 5) and Criollo (n = 5) horses were subjected to 2 different tests on a treadmill, one consisting of short-duration and rapid-acceleration training (TRA) that was mostly anerobic and the other of long-duration and slow-acceleration training (TLD) that was predominantly aerobic. Blood samples were obtained before the beginning of exercise (T0) and at 6 post-exercise time points: immediately after (T1) and 30 min (T2), 3 h (T3), 12 h (T4), 24 h (T5), and 48 h (T6) after exercise. Hematocrit was determined by the microhematocrit method. Plasma and serum samples were prepared by centrifugation (1500 × g for 5 min) for plasma concentrations of fibrinogen, total serum proteins (TP), sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), and creatine-kinase (CK) serum activity. Total protein concentration and CK serum activity were determined in an automated biochemistry analyzer. Fibrinogen was determined by the heat precipitation method in microhematocrit capillary tubes. Estimated concentrations of haptoglobin (Hp) significantly decreased after TRA and estimated concentrations of alpha-1 acid glycoprotein (AGP) significantly increased after both protocols at T2. Albumin increased after the TLD exercise protocol. Changes in hematocrit, haptoglobin, and albumin concentrations in horses subjected to different treadmill exercise protocols are related to a physiological response to hemoconcentration and hemolysis. Increases of AGP in the TLD protocol suggest the release of catecholamines as a response to avoid oxidative damage to tissue.


Assuntos
Proteínas da Fase Aguda/metabolismo , Cavalos/sangue , Condicionamento Físico Animal/fisiologia , Adaptação Fisiológica , Animais , Feminino , Cavalos/genética , Cavalos/metabolismo , Masculino , Fatores de Tempo
7.
BMC Vet Res ; 15(1): 329, 2019 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-31519197

RESUMO

BACKGROUND: Equine water treadmills (WTs) are growing in popularity because they are believed to allow for high resistance, low impact exercise. However, little is known about the effect of water height on limb loading. The aim of this study was to evaluate the effect of water height and speed on segmental acceleration and impact attenuation during WT exercise in horses. Three uniaxial accelerometers (sampling rate: 2500 Hz) were secured on the left forelimb (hoof, mid-cannon, mid-radius). Horses walked at two speeds (S1: 0.83 m/s, S2: 1.39 m/s) and three water heights (mid-cannon, carpus, stifle), with a dry WT control. Peak acceleration of each segment was averaged over five strides, attenuation was calculated, and stride frequency was estimated by the time between successive hoof contacts. Linear mixed effects models were used to examine the effects of water height, speed, and accelerometer location on peak acceleration, attenuation and stride frequency (p < 0.05). RESULTS: Peak acceleration at all locations was lower with water of any height compared to the dry control (p < 0.0001). Acceleration was reduced with water at the height of the stifle compared to mid-cannon water height (p = 0.02). Water at the height of the stifle attenuated more impact than water at the height of the cannon (p = 0.0001). CONCLUSIONS: Water immersion during treadmill exercise reduced segmental accelerations and increased attenuation in horses. WT exercise may be beneficial in the rehabilitation of lower limb injuries in horses.


Assuntos
Extremidades/fisiologia , Cavalos/fisiologia , Condicionamento Físico Animal/fisiologia , Água , Aceleração , Animais , Fenômenos Biomecânicos , Feminino , Marcha , Masculino , Condicionamento Físico Animal/métodos
8.
Life Sci ; 235: 116834, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31493478

RESUMO

Obesity has a positive relation to non-alcoholic fatty liver disease (NAFLD) and studies have demonstrated that strength training can regulate lipid accumulation in the hepatocytes of obese rats. AIMS: Our aim is to evaluate the effects of high fat diet and strength training on markers of oxidation and lipogenesis in the liver of Wistar rats. MAIN METHODS: Forty Wistar rats were divided into four groups (n = 10): control (CTL), strength training (TR), high fat diet consumption (HF) and high fat diet consumption with strength training (HFT). Animals were subjected to physical strength training and high fat diet consumption for 12 weeks, 3 session per week. Then, the animals were euthanized, and liver markers were evaluated via immunolabeling. KEY FINDINGS: Our results indicated that strength training reduced the expression of adiposity as well as the accumulation of glycogen and lipids in the liver. This reduction of fatty acid (FA) stored in hepatocytes is related to reduction of proteins linked to ß-oxidation such as Fas/CD95, LIMP-II and CD36, as well as other proteins linked to lipogeneses such as SREBP-1. SIGNIFICANCE: Finally, we observed that high fat diet can alter lipogenesis and reduce ß-oxidation promoted hepatic fat accumulation. In conclusion, there was a reduction of obesity-related hepatic lipogenesis after 12 weeks of strength training.


Assuntos
Metabolismo dos Lipídeos , Fígado/metabolismo , Obesidade/metabolismo , Condicionamento Físico Animal/fisiologia , Animais , Biomarcadores/metabolismo , Dieta Hiperlipídica/efeitos adversos , Glicogênio/metabolismo , Lipogênese , Masculino , Oxirredução , Proteínas/metabolismo , Ratos
9.
Life Sci ; 235: 116835, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31493480

RESUMO

Sleep is crucial to improve athlete performance and their circadian rhythm, but sleep patterns may be disturbed because athletes participate in several competitions. In addition, intensive training programs can cause muscle pain and psychological stress in athletes, resulting in a lack of sleep. Sleep also plays a critical role in the recovery of muscle injury induced by exercise. The current study evaluated the effect of sleep deprivation on the recovery of muscle injury induced by high-intensity exercise in a mouse model. In this study, 28 mice were randomly assigned to four groups (N = 7): control (Control), exercise (EX), sleep deprivation (SD), and sleep deprivation with exercise (EX+SD). The mice from the EX and EX+SD groups were subjected to high-intensity swimming. The results showed that 72-h sleep deprivation increased food intake and reduced body weight. However, the manipulation of 8-week exercise and/or 72-h sleep deprivation did not have any effect in the elevated plus maze task and tail suspension test. Interestingly, the EX+SD group exhibited improved memory performance in the Morris water maze and impaired motor activity in the open field test. According to the TNF-α level and aspartate aminotransferase (AST), and creatine phosphokinase (CK) activities, only the EX+SD group exhibited muscle impairment. Overall, high-intensity exercise may cause muscle injury, and adequate sleep can recover muscle damage. However, sleep deprivation reduces protein synthesis, which decreases the ability to restore muscle damage and aggravates the harmful effect of high-intensity exercise.


Assuntos
Músculos/lesões , Músculos/fisiopatologia , Condicionamento Físico Animal/fisiologia , Recuperação de Função Fisiológica/fisiologia , Privação do Sono/fisiopatologia , Animais , Aspartato Aminotransferases/metabolismo , Creatina Quinase/metabolismo , Resposta de Imobilidade Tônica/fisiologia , Masculino , Aprendizagem em Labirinto/fisiologia , Camundongos , Atividade Motora/fisiologia , Músculos/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
10.
Vet J ; 250: 24-27, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31383416

RESUMO

Epiglottic entrapment is a condition in racing horses, associated with abnormal respiratory noises and exercise intolerance. Epiglottic entrapment has been linked to both poor and superior athletic performance, leading to concerns regarding whether surgery is indicated, and whether surgical correction may have a deleterious effect on future race performance. The objective of the current study was to assess the race-day performance of horses racing with epiglottic entrapment and the effect of surgical correction on performance outcomes using an intra-oral technique in anaesthetised horses. A case-control study was conducted at the Singapore Turf Club from 2008 to 2011. Controls were selected 1:1 to cases, based on Malaysian Racing Authority number. The performance of horses racing with epiglottic entrapment was recorded and post-surgery race performance was described. Further, post-surgery race performance was compared between cases and with non-case controls. Twenty horses raced with epiglottic entrapment were retrospectively enrolled. There was a significant difference in racing performance in case horses racing with and without epiglottic entrapment (P < 0.001). Fourteen horses finished in the top three post-surgery, compared to one horse finishing in the top three when running with epiglottic entrapment present. There was no significant difference between the performance of case horses (n = 33) post-surgery and controls (number of wins P = 0.20; and places P = 0.62). The intra-oral release of epiglottic entrapment is a suitable technique to resolve epiglottic entrapment. This study may assist veterinarians advising clients in the decision-making process when epiglottic entrapment is diagnosed in a racehorse.


Assuntos
Doenças dos Cavalos/fisiopatologia , Doenças dos Cavalos/cirurgia , Cavalos/fisiologia , Doenças da Laringe/veterinária , Condicionamento Físico Animal/fisiologia , Esportes , Animais , Estudos de Casos e Controles , Feminino , Cavalos/cirurgia , Doenças da Laringe/fisiopatologia , Doenças da Laringe/cirurgia , Masculino , Estudos Retrospectivos , Corrida , Singapura
11.
Pesqui. vet. bras ; 39(8): 668-671, Aug. 2019. tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1040732

RESUMO

The aim of this study was to evaluate the serum amyloid A (SAA) and biomarkers of muscle activity of horses submitted to show jumping activity. To do this, the variables SAA, glucose, lactate and the biomarkers creatine kinase (CK) and aspartate amino transferase (AST) were evaluated in 10 horses submitted to the show jumping exercise in a tournament for beginners. The evaluations occurred before exercise (T0), immediately after (T1), 30 minutes (T2), 60 minutes (T3) and 24 hours after the end (T4). Data were evaluated using analysis of variance for repeated measures. The statistical software SAEG 9.1 was used to verify the level of significance between the moments for P<0.05. Glucose presented a difference between the moments T0 (97.7±13.3mg/dL) and T1 (79.7±14.1mg/dL). Lactate presented elevation in T1 (15.3±6.1mmol/L) compared to the others T0 (3.8±0.8mmol/L), T2 (6.5±3.9mmol/L), T3 (5.3±2.2mmol/L) and T4 (5.1±1.6mmol/L). The CK showed a significant difference between T0 (82.8±51.2U/L) and T1 (140.1±58.5U/L) and between T4 (74.4±43.1U/L) with T1 (140.1±58.5U/L). The AST presented no difference between moments. The show jumping activity with one-meter obstacles did not induce changes in the SAA protein between the moments.(AU)


O objetivo deste estudo foi avaliar a amilóide sérica A (SAA) e biomarcadores de atividade muscular de equinos submetidos a atividade de salto, ou hipismo clássico. Para tanto, foram avaliadas as variáveis SAA, glicose, lactato e os biomarcadores creatina quinase (CK) e aspartatoaminotransferase (AST) em 10 equinos submetidos ao exercício de saltos em torneio para iniciantes. As avaliações ocorreram antes do exercício (T0), imediatamente após (T1), 30 minutos (T2), 60 minutos (T3) e 24 horas após o término (T4). Os dados foram avaliados utilizando análise de variância para medidas repetidas. O software estatístico SAEG 9.1 foi utilizado para verificar o nível de significância entre os momentos para P<0,05. A glicose diferenciou-se entre os momentos T0 (97.7±13.3mg/dL) e T1 (79.7±14.1mg/dL). O lactado apresentou elevação comparada com o momento T1(15.3±6.1mmol/L) e os demais T0 (3.8±0.8mmol/L), T2 (6.5±3.9mmol/L), T3 (5.3±2.2mmol/L) e T4 (5.1±1.6mmol/L). A CK mostrou diferença significativa entre T0 (82.8±51.2U/L) e T1 (140.1±58.5U/L) e entre T4 (74.4±43.1U/L) com T1 (140.1±58.5U/L). A AST não apresentou diferença entre os momentos. A atividade de hipismo clássico com obstáculos de um metro não induziu alterações na proteína SAA entre os momentos.(AU)


Assuntos
Animais , Condicionamento Físico Animal/fisiologia , Biomarcadores , Cavalos/fisiologia , Amiloide/sangue , Atividade Motora , Proteínas da Fase Aguda
12.
Braz J Med Biol Res ; 52(7): e8429, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31314852

RESUMO

The present study aimed to analyze age-related changes to motor coordination, balance, spinal cord oxidative biomarkers in 3-, 6-, 18-, 24-, and 30-month-old rats. The effects of low-intensity exercise on these parameters were also analyzed in 6-, 18-, and 24-month-old rats. Body weight, blood glucose, total cholesterol, and high-density lipoprotein (HDL) cholesterol were assessed for all rats. The soleus muscle weight/body weight ratio was used to estimate skeletal muscle mass loss. Body weight increased until 24 months; only 30-month-old rats exhibited decreased blood glucose and increased total cholesterol and HDL cholesterol. The soleus muscle weight/body weight ratio increased until 18 months, followed by a small decrease in old rats. Exercise did not change any of these parameters. Stride length and step length increased from adult to middle age, but decreased at old age. Stride width increased while the sciatic functional index decreased in old rats. Performance in the balance beam test declined with age. While gait did not change, balance improved after exercise. Aging increased superoxide anion generation, hydrogen peroxide levels, total antioxidant capacity, and superoxide dismutase activity while total thiol decreased and lipid hydroperoxides did not change. Exercise did not significantly change this scenario. Thus, aging increased oxidative stress in the spinal cord, which may be associated with age-induced changes in gait and balance. Regular low-intensity exercise is a good alternative for improving age-induced changes in balance, while beneficial effects on gait and spinal cord oxidative biomarkers cannot be ruled out because of the small number of rats investigated (n=5 or 6/group).


Assuntos
Fatores Etários , Biomarcadores/sangue , Marcha/fisiologia , Estresse Oxidativo/fisiologia , Condicionamento Físico Animal/fisiologia , Equilíbrio Postural/fisiologia , Medula Espinal/fisiologia , Animais , Biomarcadores/metabolismo , Glicemia/análise , Peso Corporal/fisiologia , Colesterol/sangue , Lipoproteínas HDL/sangue , Masculino , Ratos , Ratos Wistar , Medula Espinal/metabolismo
13.
Life Sci ; 232: 116508, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31278948

RESUMO

AIM: Fluoxetine, one of the first newer SSRI antidepressant, is an extremely popular treatment for depression that could improve mental health problems. Many recent studies have suggested that SSRI have potential beneficial effects on skeletal muscle tissue. MAIN METHOD: We evaluated the potential beneficial effects of oral fluoxetine (18 mg/kg/day for 6 weeks) on muscle performance, after 6 weeks of physical exercise on treadmill. Male mice were randomly assigned to four groups (n = 12 per group) for treatment. Each group received treatment with following specifications: 1) no exercise with vehicle treatment (SED-S); 2) no exercise with fluoxetine treatment (SED-F); 3) exercise with vehicle treatment (EX-S); and 4) exercise with fluoxetine treatment (EX-F). Exercise performances were assessed based on the exhaustive running time and forelimb grip strength, anxious behavior by elevated plus-maze and open-field tests. Mitochondrial enzymes activity and ROS production were measured in the gastrocnemius and soleus muscles. KEY FINDING: Fluoxetine treatment had a significant effect on maximal aerobic capacity in mice without exercise, but more significant effects on gripping strength and anxiety when combined with exercise training, e.g. increased strength and decreased anxiety. SIGNIFICANCE: Fluoxetine treatment and exercise stimulation also had synergistic effects on strength and increased mitochondrial activity, cellular oxidative and antioxidant capacity in two different muscles.


Assuntos
Fluoxetina/farmacologia , Esforço Físico/efeitos dos fármacos , Animais , Antioxidantes/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Mitocôndrias/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Oxirredução , Estresse Oxidativo , Condicionamento Físico Animal/fisiologia , Resistência Física/efeitos dos fármacos
14.
BMC Vet Res ; 15(1): 237, 2019 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-31288807

RESUMO

BACKGROUND: Exercise testing in conjunction with measurement of cardiac biomarkers NT-proBNP and cTnI is a useful tool for monitoring the effect of treatment on cardiac patients. Administering Pimobendan in dogs with degenerative mitral valve disease (DMVD) and cardiomegaly results in delaying the onset of clinical symptoms and prolonging life. Its effect in dogs with DMVD without cardiomegaly has not been well examined. The aim of the current study was to investigate the effect of administering Pimobendan in dogs with DMVD without cardiomegaly using exercise testing in conjunction with measuring cardiac biomarkers in addition to echocardiography. Twenty-one dogs with asymptomatic DMVD without echocardiographic signs of cardiomegaly participated in a randomised, double-blinded trial. Dogs were divided into a Pimobendan-group (n = 11) and a placebo-group (n = 10) in a double-blinded study design and underwent a standardised submaximal exercise test (SSET). One dog in the Pimobendan-group was retrospectively removed from the study after being diagnosed with Leishmaniosis. Cardiac biomarkers NT-proBNP and cTnI were measured before and after exercise. Follow-up appointments were performed at days 90 and 180. RESULTS: Dogs in the Pimobendan-group had significantly lower post-exercise NT-proBNP-levels after being administered Pimobendan than at the beginning of the study. They also had lower pre- and post-exercise-NT-proBNP-levels than those dogs in the placebo-group. There was neither a significant difference regarding the measured cTnI levels nor an increase in cTnI between the groups at any time. CONCLUSIONS: Pimobendan lowers NT-proBNP in dogs with presymptomatic mitral valve disease without cardiomegaly before and after submaximal exercise. This indicates a reduction in cardiac wall stress. If dogs with asymptomatic DMVD without cardiomegaly benefit from treatment with Pimobendan (for example, through a longer survival time) warrants further investigation.


Assuntos
Doenças do Cão/sangue , Doenças do Cão/tratamento farmacológico , Teste de Esforço/veterinária , Doenças das Valvas Cardíacas/veterinária , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Piridazinas/uso terapêutico , Troponina I/sangue , Animais , Biomarcadores/sangue , Cães , Feminino , Doenças das Valvas Cardíacas/sangue , Doenças das Valvas Cardíacas/tratamento farmacológico , Masculino , Condicionamento Físico Animal/fisiologia , Piridazinas/farmacologia , Distribuição Aleatória , Estresse Fisiológico/efeitos dos fármacos , Resultado do Tratamento
15.
Life Sci ; 232: 116629, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31276687

RESUMO

AIMS: To investigate the effects of moderate aerobic physical training on cardiac function and morphology as well as on the levels of glial cell-derived neurotrophic factor (GDNF), nerve growth factor (NGF) and brain derived neurotrophic factor (BDNF) of animals infected with the Y strain of Trypanosoma cruzi. MAIN METHODS: Twenty-eight male C57BL/6 mice were distributed into 4 groups: sedentary control (SC), trained control (TC), sedentary infected (CHC) and trained infected (CHT). The infection was performed by intraperitoneal injection of trypomastigote forms and the animals were adapted to treadmill in the week before the beginning of the training protocol, initiated 45 days post infection. Maximal exercise test (TEM) was performed at the baseline as well as at the end of the 4th, 8th and 12th weeks of training. At the end of the 12th week, all animals were evaluated for cardiac morphology and function by echocardiography. KEY FINDINGS: CHC group showed a larger area of right ventricle (RVA), increased end-systolic volume and reduction in ejection fraction (EF), stroke volume (SV), cardiac output (CO) and fractional area change (FAC). The training reduced the RVA and improved the FAC of chagasic animals. GDNF level was higher in TC and CHC groups compared to SC in heart and BDNF levels were higher in CHC compared to SC in heart and serum. SIGNIFICANCE: Physical training ameliorated the cardiac function of infected animals and promoted adjusts in BDNF and GDNF levels. These findings evidenced these neurotrophins as possible biomarkers of cardiac function responsive to exercise stimulus.


Assuntos
Tolerância ao Exercício/fisiologia , Condicionamento Físico Animal/métodos , Condicionamento Físico Animal/fisiologia , Animais , Biomarcadores/sangue , Fator Neurotrófico Derivado do Encéfalo/análise , Fator Neurotrófico Derivado do Encéfalo/fisiologia , Débito Cardíaco , Doença de Chagas/metabolismo , Modelos Animais de Doenças , Ecocardiografia , Teste de Esforço , Fator Neurotrófico Derivado de Linhagem de Célula Glial/análise , Fator Neurotrófico Derivado de Linhagem de Célula Glial/fisiologia , Coração/fisiologia , Testes de Função Cardíaca , Ventrículos do Coração/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fator de Crescimento Neural/análise , Fator de Crescimento Neural/fisiologia , Fatores de Crescimento Neural/metabolismo , Fatores de Crescimento Neural/fisiologia , Volume Sistólico/fisiologia , Trypanosoma cruzi/patogenicidade
16.
Life Sci ; 232: 116604, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31260684

RESUMO

Chronic kidney disease (CKD) patients present L-arginine (L-arg) deficiency and L-arg supplementation has been used as a treatment. In addition, sarcopenia is another common problem in CKD population, resistance training (RT) is one of the conservative strategies developed to prevent CKD progression, and however there are no evidences of a combination of these two strategies to treat CKD outcomes. The aim of this study was to evaluate the effects of oral L-arg supplementation combined with RT in an experimental model of CKD. Twenty-five Munich-Wistar male rats, 8-week-old were divided in 5 groups: Sham (sedentary control), Nx (CKD sedentary), Nx L-arg (CKD sedentary supplemented with 2% of L-arg), Nx RT (CKD exercised) Nx RT + L-arg (CKD exercised and supplemented with 2% of L-arg). CKD model was obtained by a subtotal 5/6 nephrectomy. RT was performed on a ladder climbing, three weekly sessions on non-consecutive days, with an intensity of 70% maximum carrying capacity. They were submitted to RT and/or L-arg supplementation for 10 weeks. There was a significant improvement in muscle strength, renal function, anti-inflammatory cytokines, arginase metabolism and renal fibrosis after RT. However, the combination of RT and L-arg impaired all the improvements promoted by RT alone. The L-arg supplementation alone did not impair renal fibrosis and renal function. In conclusion, RT improved inflammatory balance, muscle strength, renal function and consequently decreased renal fibrosis. Nevertheless, the association with L-arg supplementation prevented all these effects promoted by RT.


Assuntos
Arginina/farmacologia , Condicionamento Físico Animal/fisiologia , Insuficiência Renal Crônica/dietoterapia , Animais , Arginina/metabolismo , Citocinas/metabolismo , Suplementos Nutricionais , Progressão da Doença , Fibrose/metabolismo , Rim/metabolismo , Masculino , Força Muscular/efeitos dos fármacos , Músculo Esquelético/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Condicionamento Físico Animal/métodos , Ratos , Ratos Wistar , Insuficiência Renal Crônica/metabolismo , Treinamento de Resistência/métodos
17.
Acta Cir Bras ; 34(5): e201900503, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31166462

RESUMO

PURPOSE: To analyze the muscle changes with high-intensity aerobic training (HIAT) in an animal model of renal disease (RD). METHODS: Twenty one adult Wistar rats were divided into 3 groups: healthy sedentary (HS), RD sedentary (RDS), RD aerobic training (RDAT). RDS and RDAT were subjected to unilateral renal ischemia-reperfusion (10 min) and 21days after that, RDAT was subjected to 6 weeks HIAT (swimming). Serum creatinine (Cr) and muscle morphometry (cross-sectional area = CSA) of gastrocnemius were analyzed. RESULTS: Cr was higher (p = 0.0053) in RDS (0.82 ± 0.04) than in the others (RDAT 0.55 ± 0.04; HS 0.55 ± 0.04). Morphometric analysis (class interval of CSA in µm2/absolute frequency of muscle fibers in each class) indicated that 50th percentile occurred in: HS 7th class (3000.00-3499.00/515), RDS, 8th class (3500.00-3999.00/484), RDAT 5th class (2000.00-2499.00/856). CSA of largest fibers in RDS, RDAT, HS was 9953.00 µm2, 9969.00 µm2,11228.00 µm2, respectively. High frequency of fibers with lower CSA occurred in 4th, 5th, 6th and 7th class in RDA, absence of fibers into 22nd, 23rd classes (RDS and RDAT). CONCLUSION: HIAT in an animal model of RD resulted in increased the number of muscle fibers with smaller CSA.


Assuntos
Músculo Esquelético/fisiopatologia , Condicionamento Físico Animal/fisiologia , Insuficiência Renal/fisiopatologia , Animais , Peso Corporal/fisiologia , Creatinina/sangue , Modelos Animais de Doenças , Rim/irrigação sanguínea , Rim/fisiopatologia , Fibras Musculares Esqueléticas/fisiologia , Ratos Wistar , Valores de Referência , Traumatismo por Reperfusão/fisiopatologia , Reprodutibilidade dos Testes , Comportamento Sedentário , Natação/fisiologia
18.
Psychopharmacology (Berl) ; 236(7): 2155-2171, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31161451

RESUMO

RATIONALE: Exercise shows promise as a treatment option for addiction; but in order to prevent relapse, it may need to be introduced early in the course of treatment. OBJECTIVE: We propose that exercise, by upregulating dorsal medial prefrontal cortex (dmPFC)-nucleus accumbens (NAc) transmission, offsets deficits in pathways targeting glutamate, BDNF, and dopamine during early abstinence, and in doing so, normalizes neuroadaptations that underlie relapse. METHODS: We compared the effects of exercise (wheel running, 2-h/day) during early (days 1-7), late (days 8-14), and throughout abstinence (days 1-14) to sedentary conditions on cocaine-seeking and gene expression in the dmPFC and NAc core of male rats tested following 24-h/day extended-access cocaine (up to 96 infusions/day) or saline self-administration and protracted abstinence (15 days). Based on these data, we then used site-specific manipulation to determine whether dmPFC metabotropic glutamate receptor5 (mGlu5) underlies the efficacy of exercise. RESULTS: Exercise initiated during early, but not late abstinence, reduced cocaine-seeking; this effect was strongly associated with dmPFC Grm5 expression (gene encoding mGlu5), and modestly associated with dmPFC Grin1 and Bdnf-IV expression. Activation of mGlu5 in the dmPFC during early abstinence mimicked the efficacy of early-initiated exercise; however, inhibition of these receptors prior to the exercise sessions did not block its efficacy indicating that there may be redundancy in the mechanisms through which exercise reduces cocaine-seeking. CONCLUSION: These findings indicate that addiction treatments, including exercise, should be tailored for early versus late phases of abstinence since their effectiveness will vary over abstinence due to the dynamic nature of the underlying neuroadaptations.


Assuntos
Transtornos Relacionados ao Uso de Cocaína/metabolismo , Transtornos Relacionados ao Uso de Cocaína/terapia , Cocaína/administração & dosagem , Condicionamento Físico Animal/fisiologia , Córtex Pré-Frontal/metabolismo , Receptor de Glutamato Metabotrópico 5/metabolismo , Animais , Comportamento Aditivo/metabolismo , Comportamento Aditivo/prevenção & controle , Comportamento Aditivo/psicologia , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Transtornos Relacionados ao Uso de Cocaína/psicologia , Inibidores da Captação de Dopamina/administração & dosagem , Masculino , Atividade Motora/efeitos dos fármacos , Atividade Motora/fisiologia , Condicionamento Físico Animal/métodos , Condicionamento Físico Animal/psicologia , Córtex Pré-Frontal/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Recidiva , Corrida/fisiologia , Corrida/psicologia , Autoadministração
19.
Nat Commun ; 10(1): 2767, 2019 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-31235694

RESUMO

The coactivator PGC-1α1 is activated by exercise training in skeletal muscle and promotes fatigue-resistance. In exercised muscle, PGC-1α1 enhances the expression of kynurenine aminotransferases (Kats), which convert kynurenine into kynurenic acid. This reduces kynurenine-associated neurotoxicity and generates glutamate as a byproduct. Here, we show that PGC-1α1 elevates aspartate and glutamate levels and increases the expression of glycolysis and malate-aspartate shuttle (MAS) genes. These interconnected processes improve energy utilization and transfer fuel-derived electrons to mitochondrial respiration. This PGC-1α1-dependent mechanism allows trained muscle to use kynurenine metabolism to increase the bioenergetic efficiency of glucose oxidation. Kat inhibition with carbidopa impairs aspartate biosynthesis, mitochondrial respiration, and reduces exercise performance and muscle force in mice. Our findings show that PGC-1α1 activates the MAS in skeletal muscle, supported by kynurenine catabolism, as part of the adaptations to endurance exercise. This crosstalk between kynurenine metabolism and the MAS may have important physiological and clinical implications.


Assuntos
Metabolismo Energético/fisiologia , Fadiga/fisiopatologia , Cinurenina/metabolismo , Músculo Esquelético/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Adaptação Fisiológica , Animais , Aspartato Aminotransferases/metabolismo , Ácido Aspártico/metabolismo , Carbidopa/farmacologia , Respiração Celular/efeitos dos fármacos , Respiração Celular/fisiologia , Metabolismo Energético/efeitos dos fármacos , Glicólise/fisiologia , Malatos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Modelos Animais , Músculo Esquelético/fisiopatologia , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Condicionamento Físico Animal/fisiologia , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Transaminases/antagonistas & inibidores , Transaminases/metabolismo
20.
Life Sci ; 231: 116542, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31176781

RESUMO

AIM: To compare the effect of 150 min vs. 300 min of weekly moderate intensity exercise training on the activation of the opioid system and apoptosis in the hearts of a diet-induced obesity model. METHODS: Male Wistar rats were fed with either control (CON) or high fat (HF) diet for 32 weeks. At the 20th week, HF group was subdivided into sedentary, low (LEV, 150 min·week-1) or high (HEV, 300 min·week-1) exercise volume. After 12 weeks of exercise, body mass gain, adiposity index, systolic blood pressure, cardiac morphometry, apoptosis biomarkers and opioid system expression were evaluated. RESULTS: Sedentary animals fed with HF presented pathological cardiac hypertrophy and higher body mass gain, systolic blood pressure and adiposity index than control group. Both exercise volumes induced physiological cardiac hypertrophy, restored systolic blood pressure and improved adiposity index, but only 300 min·week-1 reduced body mass gain. HF group exhibited lower proenkephalin, PI3K, ERK and GSK-3ß expression, and greater activated caspase-3 expression than control group. Compared to HF, no changes in the cardiac opioid system were observed in the 150 min·week-1 of exercise training, while 300 min·week-1 showed greater proenkephalin, DOR, KOR, MOR, Akt, ERK and GSK-3ß expression, and lower activated caspase-3 expression. CONCLUSION: 300 min·week-1 of exercise training triggered opioid system activation and provided greater cardioprotection against obesity than 150 min·week-1. Our findings provide translational aspect with clinical relevance about the critical dose of exercise training necessary to reduce cardiovascular risk factors caused by obesity.


Assuntos
Cardiomegalia/metabolismo , Condicionamento Físico Animal/fisiologia , Receptores Opioides/fisiologia , Adiposidade , Animais , Apoptose/fisiologia , Pressão Sanguínea , Peso Corporal , Dieta Hiperlipídica , Encefalinas/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Coração/fisiopatologia , Sistema de Sinalização das MAP Quinases/fisiologia , Masculino , Obesidade/metabolismo , Obesidade/fisiopatologia , Fosfatidilinositol 3-Quinase/metabolismo , Condicionamento Físico Animal/métodos , Precursores de Proteínas/metabolismo , Ratos , Ratos Wistar
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