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1.
Equine Vet J ; 52(1): 52-58, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30989701

RESUMO

BACKGROUND: Epiglottic entrapment can occur in yearling Thoroughbreds (TB); however, race performance following surgical correction is unknown. OBJECTIVES: To determine the race performance of horses treated surgically for epiglottic entrapment as yearlings as compared to an untreated cohort. A second objective was to identify risk factors for treated horses not racing post-operatively. STUDY DESIGN: Retrospective cohort and case-control studies. METHODS: Medical (1989-2014) and race records of 66 treated TB racehorses were reviewed. Observed abnormalities on pre- and post-operative endoscopic images and surgical method were recorded. Race records (EquineLine) were recorded. Racing performance of treated yearling TBs and two of their maternal half-siblings, which were used as the untreated cohort, was evaluated in a cohort study. A case-control study was used to investigate risk factors for not racing post-operatively among treated horses. Quarterly starts and earnings were compared to an untreated cohort. Survival analysis was used to assess career longevity. Rates of racing and earnings were compared between groups using Poisson and negative binomial regression respectively. Associations between clinical variables and not racing post-surgery were evaluated using logistic regression. RESULTS: Sixty-six treated horses were identified, 65 of which had at least one half-sibling. Proportions of horses that raced were similar for treated and maternal cohorts (70.0 vs. 70.8%, P = 0.9). Treated horses performed similarly to untreated horses. In treated horses, epiglottic entrapment with abnormal right arytenoid movement was associated with never racing (OR 15.40, 95% CI 1.64-144.23, P = 0.02). More females were affected by epiglottic entrapment than males (47/66 vs. 19/66 respectively, P<0.001). MAIN LIMITATIONS: The retrospective design over a prolonged period of time with cases obtained from a single hospital population. Low case numbers likely influenced the outcome of the multivariable analysis. CONCLUSIONS: Thoroughbred racehorses treated in their yearling year for epiglottic entrapment had no differences in performance variables compared to their untreated cohort. Epiglottic entrapment with abnormal right arytenoid movement might decrease odds of racing post-operatively.


Assuntos
Epiglote/cirurgia , Doenças dos Cavalos/cirurgia , Animais , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Cavalos , Doenças da Laringe/veterinária , Masculino , Condicionamento Físico Animal , Estudos Retrospectivos , Corrida , Esportes
2.
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
3.
Life Sci ; 242: 117182, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31863770

RESUMO

AIMS: The present study was designed to compare the effects of a low-fat diet (LF), calorie restriction (CR), quercetin (Que) and exercise (Ex) on hepatic steatosis in a high-fat (HF) diet-induced obesity prone (OP) model in the perspective of microRNA (miR)-dependent thyroid hormone (TH) synthesis and action. MAIN METHODS: Male C57BL/6J mice were administered a HF diet for 10 weeks to induce OP phenotype and then divided into 5 groups, HF diet (OP-HF), LF diet (OP-LF), 70% CR (OP-CR), 0.05% Que (OP-Que) and a treadmill exercise regimen (OP-Ex); one additional group fed LF diet served as control (LF). 7 weeks later, serum indexes, metabolic alterations, redox status and histological appearance in the thyroid and liver, and TH related miRs with their targets expressions were determined. KEY FINDINGS: No significance on T3 levels was observed among the six groups. LF, CR, Que and Ex significantly ameliorated HF-induced hepatic steatosis to varying degrees, inhibited T4 production via differentially elevating miR-339, miR-383 and miR-146b to decrease NIS expression and regulating miR-200a/Nrf2 to maintain redox status in the thyroid. Furthermore, these four interventions differentially and significantly decreased miR-383 and miR-146b to elevate TRb and DIO1 expression, and subsequent TH responsive lipid metabolism genes regulation. Among them, the effects of CR on hepatic steatosis were the most prominent. SIGNIFICANCE: Our data indicated that amelioration of hepatic steatosis by LF, CR, Que and Ex resulted in many shared, but also many differential changes in the miR-dependent TH production and action.


Assuntos
Dieta com Restrição de Gorduras , Fígado Gorduroso/terapia , MicroRNAs/fisiologia , Obesidade/complicações , Condicionamento Físico Animal , Hormônios Tireóideos/metabolismo , Animais , Restrição Calórica , Fígado Gorduroso/dietoterapia , Fígado Gorduroso/etiologia , Hipolipemiantes/uso terapêutico , Lipídeos/análise , Fígado/química , Masculino , Camundongos Endogâmicos C57BL , MicroRNAs/metabolismo , Estresse Oxidativo , Quercetina/uso terapêutico
4.
Chin J Physiol ; 62(6): 241-244, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31793459

RESUMO

The aim of this study was to identify force-velocity and power-velocity curves in climbing activity protocols, used as dynamic resistance exercise in rats. Eighteen 45-day-old male Wistar rats (weight = 211.9 ± 5.2 g) were evaluated. After familiarization to the climbing procedure, the animals performed an incremental climbing test (load relative to 75% of the body mass at first stage, followed by 30 g increments with and 120 s recovery between climbs) to determine the maximum carrying capacity (MCC). After this, the animals climbed with different loads (without load, 10%, 20%, 30%, 40%, 50%, 75%, 90%, and 100% of MCC) with 120 s recovery between climbs. Time for each climb was recorded to calculate the mechanical power. The peak power was reached at 30% of MCC. For the force-velocity curve, an inversely proportional relation was observed between force and velocity, as expected, greater forces were expressed in lower velocities. Therefore, our results suggest that training at 30% of MCC should be encouraged aiming the target for greater power output and 90%-100% of MCC should be the load aiming for strength training in climbing activities for rats.


Assuntos
Condicionamento Físico Animal , Treinamento de Resistência , Animais , Teste de Esforço , Masculino , Força Muscular , Músculo Esquelético , Ratos , Ratos Wistar , Levantamento de Peso
5.
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
6.
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
7.
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
8.
Adv Exp Med Biol ; 1185: 451-455, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31884653

RESUMO

Physical exercise is protective in rodent models of retinal injury and disease. Data suggest that this is in part mediated by brain-derived neurotrophic factor (BDNF) signal transduction. It has been hypothesized that exercised-induced neuroprotection may be mediated by increases in circulating lactate that in turn alter BDNF secretion. We therefore tested whether mice undergoing a treadmill running regimen previously shown to be protective in a mouse model of retinal degeneration (RD) have increased serum levels of lactate. Lactate levels in exercised and non-exercised mice were statistically indistinguishable. A role for circulating lactate in exercise-induced retinal protection is unsupported.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/metabolismo , Ácido Láctico/sangue , Neuroproteção , Condicionamento Físico Animal , Degeneração Retiniana/prevenção & controle , Animais , Camundongos , Retina , Transdução de Sinais
9.
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
10.
Nat Med ; 25(11): 1761-1771, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31700184

RESUMO

A sedentary lifestyle, chronic inflammation and leukocytosis increase atherosclerosis; however, it remains unclear whether regular physical activity influences leukocyte production. Here we show that voluntary running decreases hematopoietic activity in mice. Exercise protects mice and humans with atherosclerosis from chronic leukocytosis but does not compromise emergency hematopoiesis in mice. Mechanistically, exercise diminishes leptin production in adipose tissue, augmenting quiescence-promoting hematopoietic niche factors in leptin-receptor-positive stromal bone marrow cells. Induced deletion of the leptin receptor in Prrx1-creERT2; Leprfl/fl mice reveals that leptin's effect on bone marrow niche cells regulates hematopoietic stem and progenitor cell (HSPC) proliferation and leukocyte production, as well as cardiovascular inflammation and outcomes. Whereas running wheel withdrawal quickly reverses leptin levels, the impact of exercise on leukocyte production and on the HSPC epigenome and transcriptome persists for several weeks. Together, these data show that physical activity alters HSPCs via modulation of their niche, reducing hematopoietic output of inflammatory leukocytes.


Assuntos
Aterosclerose/terapia , Doenças Cardiovasculares/terapia , Células-Tronco Hematopoéticas/metabolismo , Inflamação/terapia , Condicionamento Físico Animal , Tecido Adiposo/metabolismo , Animais , Aterosclerose/prevenção & controle , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/fisiopatologia , Doenças Cardiovasculares/prevenção & controle , Exercício/fisiologia , Hematopoese/genética , Hematopoese/fisiologia , Proteínas de Homeodomínio/genética , Humanos , Inflamação/fisiopatologia , Leucócitos/metabolismo , Leucocitose/fisiopatologia , Leucocitose/terapia , Camundongos , Receptores para Leptina/genética , Comportamento Sedentário , Transcriptoma/genética
11.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 35(4): 326-330, 2019 Jul 28.
Artigo em Chinês | MEDLINE | ID: mdl-31701716

RESUMO

OBJECTIVE: To investigate the effects of different intensity intermittent exercise on the body function of obese rats, and to provide basis for the prevention and treatment of obesity. METHODS: Eighty SD rats were randomly divided into normal diet group (n=20) and high-fat diet group (n=60). After adaptive feeding for 8 weeks, 8 normal diet rats and 32 high-fat obese rats were selected for follow-up experiments. The experimental rats were randomly divided into 5 groups (n=8): control diet-sedentary (CS),with ordinary feed and without any exercise; high diet-sedentary (HS), with high-fat feed feeding and without any exercise; high diet-continual exercise(HC), 60 min/day,5 days/week with 6 weeks; high diet-long time-low frequency interval exercise(HLL), 30 min/time,twice/day (intermittent 6 h), 5 days/week with 6 weeks; high diet-short time-high frequency interval exercise(HSH), 20 min/ time, 3 times/d (intermittent 3 h), 5 days/week with 6 weeks. The training intensity of rats in each exercise group was 25 m/min. After 6 weeks, rats in each groups were weighed, and resting metabolic rate(RMR), fasting blood glucose(FBG), triglyceride(TG) and other biochemical indexes were detected, and fat and muscle weight were measured. RESULTS: Before experiment, there were no significant differences in RMR, FBG and TG in each groups(P>0.05).The body weight of HSH, HLL, HC and HS groups was higher than that of CS group (P<0.05). After the experiment, RMR of the HSH,HLL and HC groups was significantly higher than that of HS and CS groups (P<0.05), but without significant difference among the HSH,HLL and HC groups (P>0.05).The body weight of HSH, HLL and HC groups was significantly lower than that of HS group (P<0.05), but the three groups was not significant (P>0.05); perirenal fat(PF), idymis fat(EF), perirenal fat/weight(PF/W) and epididymis fat/weight(EF/W) of HSH, HLL, HC group were significantly lower than those of HS group (P<0.01), while there was no statistical difference among the three groups (P>0.05). There was no significant difference in gastrocnemius(GM) and quadricep(QF) of each group (P>0.05), gastrocnemius/weight(GM/W) and quadriceps/weight (QF/W) in HSH,HLL and HC groups were higher than those of HS group (P<0.05),while there was no significant difference among HSH,HLL and HC groups (P>0.05);FEB,TG of HSH,HLL,HC group were lower than those of CS and HS group (P<0.05),but the difference with HS group was more significant (P<0.01),there was no significant difference among training groups(P>0.05). CONCLUSION: 6 weeks of intermittent exercise of different intensity had a good intervention effect on the body composition of obese rats, and high diet-short time-high frequency interval exercise (HSH) may be more effective.


Assuntos
Composição Corporal , Obesidade/terapia , Condicionamento Físico Animal , Animais , Peso Corporal , Dieta Hiperlipídica , Masculino , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
12.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 35(4): 339-345, 2019 Jul 28.
Artigo em Chinês | MEDLINE | ID: mdl-31701719

RESUMO

OBJECTIVE: To understand and analyze the rules of endurance exercise on the cerebral cortex adaptive mechanism in aged rats. METHODS: In this study, 3-month-old (n=20), 13-month-old (n=24) and 23-month-old (n=24) specific-pathogen free (SPF) male Sprague-Dawley Rat (SD) rats were divided into young (Y-SED), middle-aged (M-SED) and old-aged (O-SED) sedentary control group, and the corresponding Y-EX, M-EX and O-EX in the endurance exercise runner group. The 10-weeks of regular moderate-intensity aerobic exercise intervention were carried out in the endurance exercise runner group. The exercise mode is treadmill exercise (slope 0), and the exercise intensity gradually increases from 60%~65% of the maximum oxygen consumption (V·O2max) to 70%~75%, and the exercise time is 10 weeks. Hematoxylin and eosin (HE) staining was used to detect age-related morphological changes. The expressions of superoxide dismutase(SOD) and brain-derived neurotrophic factor (BDNF) and the expressions of synapsin 1 (SYN1) and Ca2+/calmodulin- dependent protein kinases IIα (CaMK IIα) / AMP-activated protein kinase α1(AMPKα1) / mammalian target of rapamycin (mTOR) pathway -related genes were detected. RESULTS: The cerebral cortex structure of the rats in each group showed age-related aging changes, the expression of SOD in the cortex showed a gradual decline, the expression of BDNF showed an age-increasing trend, and the expression levels of SYN1 and CaMK IIα were increased with age. The changes in AMPKα1 and SirT2 and IP3R, AKT1 and mTOR mRNA levels were increased slightly in middle-aged rats and decreased in aged rats. Compared with the rats in each sedentary control group, the nucleus of the cerebral cortex was tightly arranged and the number of nuclei observed under the microscope was increased significantly in each exercise group. Exercise promoted the expressions of SOD, BDNF and synaptophysin SYN1 in the cortex of rats, and the expression levels of SOD and BDNF in aged rats were up-regulated significantly (P< 0.01). The expression level of SYN1 in rats was up-regulated significantly (P<0.05) in the young and aged rats. The expression of CaMK IIα in the cortex of middle-aged and aged rats was up-regulated (P<0.01), while the expression level of CaMK IIα in young rats was down-regulated (P<0.01). Exercise could up-regulate the expression level of AMPKα1 in the cortex of young rats (P< 0.05), but not in middle-aged and old-age rats. Exercise could up-regulate the expression of SirT2 in the cortex of rats in all age groups (P<0.05). Exercise up-regulated the expression of phosphoinositide 3-kinase (IP3R)/ protein kinase B 1(AKT1) /mTOR in the cortex of rats, among which young IP3R was significantly up-regulated (P<0.01) in the young group, mTOR was significantly up-regulated in young and middle-aged group (P<0.01), and mTOR was also significantly up-regulated in the aged group (P<0.05). CONCLUSION: Endurance exercise up-regulates BDNF expression, regulates CaMKIIα signaling, activates AMPK signaling pathway and IP3R / AKT1 / mTOR signaling pathway, and improves synaptic plasticity in the cortex.


Assuntos
Córtex Cerebral/fisiologia , Plasticidade Neuronal , Condicionamento Físico Animal , Resistência Física , Transdução de Sinais , Fatores Etários , Animais , Masculino , Ratos , Ratos Sprague-Dawley
13.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 35(4): 366-370, 2019 Jul 28.
Artigo em Chinês | MEDLINE | ID: mdl-31701725

RESUMO

OBJECTIVE: To investigate the effects of Acorus tatarinowii Schott and its active component 5- hydroxymethyl furfural (HMF) on learning and memory and ERK/CREB signal in hippocampus of rats with exercise-induced fatigue. METHODS: SD rats were randomly divided into normal group (A), exercise group (B), exercise + HMF low, middle and high dose treatment group (C, D, E), exercise + acorus tatarinowii Schott low, middle and high dose treatment group (F, G, H), with ten rats in each group. The rats in group C, D and E were treated with HMF at the doses of 0.10, 1.00 and 3.00 mg. kg-1 by ig. The rats in group F, G and H were treated with the extracts of Acorus tatarinowii Schott at the doses of 0.12, 1.20 and 4.80 g. kg-1 by ig. Learning and memory of rats were tested by the method of water maze experiment, and the expression levels of p-ERK1/2 and p-CREB protein in hippocampus of rats were tested by the method of Western blot in the end of the experiment. RESULTS: The escape latencies of E and H groups were lower than those of groups B, C, D, F and G; and the numbers of plateau crossing were more than those of groups B, C, D, F and G and the expression levels of p-ERK1/2, p-CREB protein were higher than those of groups B, C, D, F and G , respectively(P < 0.01). There was no significant difference in the above indexes among groups A, E and H(P>0.05) except that the expression levels of p-ERK2 protein in group E were lower than those in group A and H (P<0.05). CONCLUSION: Acorus tatarinowii and its active component- HMF can improve the learning and memory of rats with exercise-induced fatigue, and the mechanism is related to the up-regulation of ERK / CREB signal in hippocampus of rats with exercise-induced fatigue.


Assuntos
Acorus/química , Fadiga/tratamento farmacológico , Furaldeído/análogos & derivados , Condicionamento Físico Animal , Animais , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Furaldeído/farmacologia , Hipocampo/metabolismo , Sistema de Sinalização das MAP Quinases , Aprendizagem em Labirinto/efeitos dos fármacos , Memória/efeitos dos fármacos , Compostos Fitoquímicos/farmacologia , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
14.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 35(4): 376-380, 2019 Jul 28.
Artigo em Chinês | MEDLINE | ID: mdl-31701727

RESUMO

OBJECTIVE: To investigate whether salidroside (Sal) plays a part in protecting myocardial cell through reducing the myocardial ischemia and the apoptosis pathway of both death receptors and mitochondria in acute exhausted rats. METHODS: Male SD rats were randomly divided into 4 groups (n=6): control group(Con), acute exhaustive swimming group (EE), low-dose and high-dose Sal pre-treatment exhaustive swimming group (SLE, SHE). Rats were treated with Sal solution (15 or 30 mg/(kg·d)) or 0.9%NaCl (3 ml/(kg·d)) by intraperitoneal injection for 15 d, respectively. The Con group did not carry out swimming training. The next day after the end of intraperitoneal administration, the rats in EE, SLE and SHE group were forced to swim until they were exhausted followed the standard of Thomas. After the end of exhaustive exercise, the rats were anesthetized and the blood samples and hearts were collected immediately. The myocardial ischemia and hypoxia area and myocardial apoptosis index (AI) were also observed. Serum ischemia modified albumin (IMA), cardiac troponin I (cTnI), brain natriuretic peptide(BNP) and myocardial cell Bcl-2-associated X protein (Bax), B-cell lymphoma-2 (Bcl-2) were determined. The expressions of myocardial TNF receptor superfamily member 6 (Fas), cytochrome C (Cyto-c), aspartate proteolytic enzyme-3(Caspase-3), aspartate proteolytic enzyme-8(Caspase-8), and aspartate proteolytic enzyme-9(Caspase-9) were detected. RESULTS: Compared with the Con group, the myocardial ischemia and hypoxia area in EE group was increased significantly. The serum levels of IMA, cTnI and BNP, AI and Bax levels and cardiac Fas, Cyto-C, Caspase-3, Caspase-8 and Caspase-9 protein expressions of EE group were also increased significantly (P<0.01), while the protein expression of Bcl-2 in cardiac tissues was decreased significantly (P<0.01). Compared with the EE group, the myocardial ischemia and hypoxia area, serum levels of IMA, cTnI and BNP, AI and Bax levels, and the protein expressions of cardiac Fas, Cyto-C, Caspase-3, Caspase-8 and Caspase-9 in Sal group were all decreased significantly(P<0.01). while the protein expression of cardiac Bcl-2 in Sal group were increased significantly (P<0.01). CONCLUSION: Sal plays a role in protecting myocardial cell through reducing the myocardial ischemia and inhibiting myocardial cell apoptosis in exhaustive exercise rats. The mechanism of reducing myocardial cell apoptosis may be related to inhibiting the expressions of Fas, Cyto-C, Caspase-3, Caspase-8, Caspase-9 and increasing the expression of Bcl-2.


Assuntos
Apoptose , Fadiga/fisiopatologia , Glucosídeos/farmacologia , Coração/efeitos dos fármacos , Isquemia Miocárdica/tratamento farmacológico , Fenóis/farmacologia , Animais , Biomarcadores/sangue , Feminino , Masculino , Miocárdio/citologia , Condicionamento Físico Animal , Ratos , Ratos Sprague-Dawley
15.
Int J Sports Med ; 40(14): 921-930, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31614382

RESUMO

Myocardial damage due to dysfunctional myocardium has been increasing, and the prognosis of pharmacological and device-based therapies remain poor. Isl1-expressing cells were thought to be progenitor cells for cardiomyocyte proliferation after specific stimuli. However, the true origin of the proliferating myocardiac cells and the role of Isl1 in adult mammals remain unresolved. In this study, Isl1-CreERT2 knock-in mouse model was constructed using CRISPR/Cas9 technology. Using tamoxifen-inducible Isl1-CreERT/Rosa26R-LacZ system, Isl1+cells and their progeny were permanently marked by lacZ-expression. X-gal staining, immunostaining, and quantitative PCR were then used to reveal the fate of Isl1+cells under physiological and exercise conditions in mouse hearts from embryonic stage to adulthood. Isl1+cells were found to localize to the sinoatrial node, atrioventricular node, cardiac ganglia, aortic arch, and pulmonary roots in adult mice heart. However, they did not act as cardiac progenitor cells under physiological and exercise conditions. Although Isl1+cells showed progenitor cell properties in early mouse embryos (E7.5), this ability was lost by E9.5. Furthermore, although the proliferation and regeneration of heart cell was observed in response to exercise, the cells associated were not Isl1 positive.


Assuntos
Coração/fisiologia , Proteínas com Homeodomínio LIM/genética , Miocárdio/citologia , Miócitos Cardíacos/citologia , Condicionamento Físico Animal , Células-Tronco/fisiologia , Fatores de Transcrição/genética , Animais , Proteína 9 Associada à CRISPR , Sistemas CRISPR-Cas , Proliferação de Células/fisiologia , Mapeamento Cromossômico , Coração/embriologia , Coração/crescimento & desenvolvimento , Masculino , Camundongos Endogâmicos C57BL
16.
Wei Sheng Yan Jiu ; 48(4): 611-620, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31601344

RESUMO

OBJECTIVE: To investigate the effect of chronic and acute swimming exercise intervention on the mitogen-activated extracellular signal-regulated kinase(MEK) and extracellular signal-regulated kinase 1(ERK1) phosphorylation level in adipose tissues of obesityinduced insulin resistance rats. METHODS: A total of 100 SD rats were randomly divided into control group(n=10) fed with normal diet and high-fat diet group(n=90) fed with high fat diet. After 8 weeks, one third rats(n=30) with upper weight in high-fat diet group were selected and randomly divided into high-fat diet sedentary group(n=10), chronic exercise group(n=10) and acute exercise group(n=10). Under another 8-week high-fat diet feeding, exercise intervention was performed according to the exercise procedure; control group was fed with normal diet for 8 weeks. After exercise intervention, visceral adipose tissues were separated and MEK and ERK1 phosphorylation level in adipose tissue was detected by Western blot method. RESULTS: Chronic exercise intervention significantly reduced body weight, visceral fat weight and visceral fat weight/body weight ratio(P<0. 01), and acute exercise intervention had no significant effect on body weight, visceral fat weight and visceral fat weight/body weight ratio. Both chronic and acute exercise intervention significantly increased body insulin sensitivity(P<0. 05), as well as significantly decreased MEK and ERK1 phosphorylation level in adipose tissues(P<0. 01). CONCLUSION: The improvement of obesity-induced insulin resistance by exercise might be related to inhibited phosphorylation of MEK and ERK1 in adipose tissues.


Assuntos
Tecido Adiposo/metabolismo , Resistência à Insulina/fisiologia , MAP Quinase Quinase 1/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Condicionamento Físico Animal , Natação , Animais , Dieta Hiperlipídica , Insulina , Fosforilação , Ratos , Ratos Sprague-Dawley
17.
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
18.
Life Sci ; 237: 116896, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31605707

RESUMO

AIMS: Population-based studies have shown that exercise has anti-atherosclerotic effects, but the mechanisms underlying this cardiac protection are poorly understood. The aim of this study was to investigate if the anti-atherosclerotic effects of exercise are associated with changes in neuropeptide Y (NPY) expression in apolipoprotein E-deficient (ApoE-/-) mice. MAIN METHODS: Thirty-one male ApoE-/- mice were randomly divided into regular exercise (5 days/week), occasional exercise (1-2 days/week), and sedentary groups. After 8 weeks, atherosclerotic burden and plaque stability were measured by histological and morphological analysis. Quantitative real-time PCR and immunohistochemistry were used to measure the expression of NPY and its receptors in the aorta. KEY FINDINGS: Eight weeks of occasional exercise was equally effective as regular exercise at preventing atherosclerotic plaque formation and enhancing atherosclerotic plaque stability. This was shown by increased plaque collagen and smooth muscle cell content and decreased plaque lipid and macrophage content. The expression of NPY and its receptors in the vasculature was decreased in the regular exercise and occasional exercise groups, and this expression was significantly correlated with the progress of atherosclerosis. Moreover, exercise may reduce the activity of macrophages by down-regulating the expression of NPY Y1 receptors, thereby reducing the release of inflammatory cytokines. SIGNIFICANCE: These results suggest that exercise training can attenuate plaque burden and enhance atherosclerotic plaque stability. The anti-atherosclerotic effect of exercise appears to be, at least in part, dependent on down-regulation of the expression of NPY and its receptors (especially Y1 receptors) in the aorta.


Assuntos
Apolipoproteínas E/fisiologia , Aterosclerose/prevenção & controle , Regulação da Expressão Gênica , Inflamação/prevenção & controle , Neuropeptídeo Y/metabolismo , Condicionamento Físico Animal , Animais , Aorta/metabolismo , Aorta/patologia , Aterosclerose/etiologia , Aterosclerose/metabolismo , Aterosclerose/patologia , Citocinas/metabolismo , Modelos Animais de Doenças , Inflamação/etiologia , Inflamação/metabolismo , Inflamação/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout para ApoE , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/patologia , Neuropeptídeo Y/genética
19.
Life Sci ; 238: 116964, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31639398

RESUMO

AIMS: The main aim of this study was to investigate the moderate versus high-load resistance training on muscle strength, hypertrophy and protein synthesis signaling in rats. METHODS: Twenty rats were randomly allocated into three groups as follow: control group (C, n = 6), high-load training (HL, n = 7) and moderate-load training (ML, n = 7). A ladder climb exercise was used to mimic resistance exercise. ML resistance training consisted of a moderate load, allowing performance at higher volume of load inherent to higher number of repetitions (8-16 climbing). HL resistance training consisted of progressively increase training load, with low volume of load (4-8 climbing). C group remained with physical activity restricted to their cage space. This experiment was conducted over a six-weeks period. Forty-eight hours after the last resistance training session the animals were euthanized for tissue collection. RESULTS: Both HL and ML regimens promoted similar increases in muscle strength, elevated protein synthesis signaling demonstrated by increased skeletal muscle total/phosphorylated P-70S6K ratio and similar increases in plantaris and FHL muscle hypertrophy, all compared to control. All these similarities were demonstrated even though testosterone/cortisol ratio was higher in HL group compared to ML and control. ML regimen caused higher total training volume and soleus muscle hypertrophy, which was not demonstrated in HL group. CONCLUSION: In conclusion, results suggest that both HL and ML induce muscle hypertrophy and increase on strength in a similar way. ML moreover seems to favor slow fiber hypertrophy due the higher training volume.


Assuntos
Adaptação Fisiológica , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Condicionamento Físico Animal/métodos , Treinamento de Resistência/métodos , Animais , Masculino , Ratos , Ratos Wistar
20.
Life Sci ; 238: 116974, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31639399

RESUMO

AIM: Analyze the effects of voluntary running during the development of pulmonary arterial hypertension (PAH) induced by monocrotaline (MCT) on the right ventricle (RV) structure, RV myocyte contractility and intracellular Ca2+ transient in rats with MCT-induced PAH. MAIN METHODS: Male Wistar rats were housed sedentary or with free access to a running wheel after MCT or saline injection for until HF or median end-point day of HF in sedentary animals (24 days). Echocardiographic examination and exercise tolerance test were carried out at specific time points of the experimental period. After euthanasia, the heart was dissected, weighed and processed for either histological or single myocyte contractility and intracellular Ca2+ transient analyzes. KEY FINDINGS: Voluntary running delayed the onset of HF (29 days) and the increase in pulmonary artery resistance, and improved exercise tolerance. In the median end-point day of HF, exercise retarded RV adverse remodeling (i.e. increase in extracellular matrix and collagen content). At this stage, exercise also delayed impairments in cell contractile function (i.e. amplitude and times to peak and to half relaxation) and intracellular calcium cycling (i.e. amplitude and times to peak and to half decay) in RV single myocytes. SIGNIFICANCE: Along with HF onset delay and physical effort tolerance enhancement, voluntary running during the development of PAH postpones pulmonary artery resistance increases, RV adverse remodeling and myocyte contractility and intracellular calcium cycling deterioration in rats. Therefore, self-paced intermittent exercise of high intensity may contribute positively to the health and survival of individuals with PAH.


Assuntos
Insuficiência Cardíaca/prevenção & controle , Hipertensão Pulmonar/complicações , Hipertrofia Ventricular Direita/prevenção & controle , Contração Muscular , Miócitos Cardíacos/patologia , Condicionamento Físico Animal , Artéria Pulmonar/patologia , Remodelação Ventricular , Animais , Cálcio , Modelos Animais de Doenças , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/patologia , Hipertrofia Ventricular Direita/etiologia , Hipertrofia Ventricular Direita/patologia , Masculino , Ratos , Ratos Wistar , Corrida
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