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2.
Exerc Sport Sci Rev ; 47(2): 75-85, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30883471

RESUMO

The gastrointestinal tract contains trillions of microbes (collectively known as the gut microbiota) that play essential roles in host physiology and health. Studies from our group and others have demonstrated that exercise independently alters the composition and functional capacity of the gut microbiota. Here, we review what is known about the gut microbiota, how it is studied, and how it is influenced by exercise training and discuss the potential mechanisms and implications for human health and disease.


Assuntos
Exercício , Microbioma Gastrointestinal , Trato Gastrointestinal/fisiologia , Animais , Humanos
3.
Med Sci Sports Exerc ; 51(8): 1635-1641, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30829964

RESUMO

Studies suggest that exercise can improve vaccination responses in humans. Chronic stress can lead to immunosuppression, and there may be a role for exercise in augmenting immune responses. PURPOSE: To investigate the effects of acute eccentric exercise (ECC) and voluntary wheel exercise training (VWR) on antibody and cell-mediated immune responses to vaccination in chronically stressed mice. We hypothesized that both ECC and VWR would attenuate chronic stress-induced reductions in vaccination responses. METHODS: Mice were randomized into four groups: control (CON), stress (S)-ECC, S-VWR, and S-sedentary (SED). Stressed groups received chronic restraint stress for 6 h·d, 5 d·wk for 3 wk. After the first week of stress, S-ECC were exercised at 17 m·min speed at -20% grade for 45 min on a treadmill and then intramuscularly injected with 100 µg of ovalbumin (OVA) and 200 µg of alum adjuvant. All other groups were also vaccinated at this time. Stress-VWR mice voluntarily ran on a wheel for the entire experiment. Plasma was collected before, and at 1, 2, and 4 wk postvaccination. Enzyme-linked immunosorbent assay was performed to analyze anti-OVA IgG and IgM antibodies. After 3 wk of chronic stress, all mice were injected with OVA into the ear to determine the delayed-type hypersensitivity. RESULTS: We found that chronic restraint stress significantly reduced body weight and caused adrenal hypertrophy. We also found both S-ECC and S-VWR groups had significantly elevated anti-OVA IgG (P < 0.05), whereas no significant differences between the two exercise groups. Neither S-ECC nor S-VWR altered anti-OVA IgM or delayed-type hypersensitivity responses compared with S-SED group. CONCLUSIONS: Acute eccentric exercise and voluntary exercise training alleviated the chronic stress-induced anti-OVA IgG reductions in vaccination responses.

4.
Behav Brain Res ; 2018 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-30243767

RESUMO

Recent data has supported a role for the gut microbiota in improving cognition and shaping behavior. Here, we assessed whether pectin, a soluble, fermentable fiber, could enhance learning and memory in mice. Two cohorts of young male C57Bl/6 J mice, C1 (n = 20) and C2 (n = 20), were obtained from Jackson Laboratory and randomized to semi-purified AIN-93 M diets containing 5% pectin (n = 10) or cellulose (n = 10). After 16 weeks, learning and memory was assessed by Morris Water Maze (MWM) and microbiota composition was analyzed by 16S rRNA sequencing. Despite identical treatment, we observed differences in learning and memory abilities between cohorts, along with distinct microbiotas. In C1, pectin-fed mice spent a higher percentage of time in the target quadrant at the 24-h probe trial of the MWM versus cellulose-fed mice; in C2, no effect of pectin was observed. In both cohorts, UniFrac distance revealed significant differences in gut microbial communities between cellulose-fed and pectin-fed mice. UniFrac analysis also revealed significantly different bacterial communities between cohorts. Further analysis demonstrated that the microbial genera Oscillospira, Bilophila, and Peptostreptococcoceae were more abundant in C1 versus C2, and positively associated with distance from the platform during the 24-h probe test. These data support previous findings that differences in the gut microbiota may play a role in host response to a dietary intervention and could partly explain irreproducibility in psychological and behavioral experiments. Further research is needed to determine if a causal relationship exists.

5.
Mayo Clin Proc ; 93(8): 1104-1110, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30077203

RESUMO

The rising incidence of obesity requires the reevaluation of our current therapeutic strategies to optimize patient outcomes. The objective of this study was to determine whether compositional and functional characteristics of the gut microbiota in adults predict responses to a comprehensive lifestyle intervention program in overweight and obese adults. We recruited 26 participants from the Mayo Clinic Obesity Treatment Research Program between August 6, 2013, and September 12, 2013, to participate in a lifestyle intervention program for weight loss. Adults aged 18 to 65 years with a body mass index of 27 to 39.9 kg/m2 and able to provide informed consent were included in the study. Fecal stool samples were obtained at baseline and after 3 months. Loss of at least 5% of baseline weight after 3 months was defined as success. Clinical characteristics and gut microbial composition and function were compared between those who achieved at least 5% and those who achieved less than 5% weight loss. After 3 months, 9 of 26 participants lost at least 5% of their weight. The mean weight loss was 7.89 kg (95% CI, 6.46-9.32 kg) in the success group and 1.51 kg (95% CI, 0.52-2.49 kg) in the less than 5% weight loss group. An increased abundance of Phascolarctobacterium was associated with success. In contrast, an increased abundance of Dialister and of genes encoding gut microbial carbohydrate-active enzymes was associated with failure to lose 5% body weight. A gut microbiota with increased capability for carbohydrate metabolism appears to be associated with decreased weight loss in overweight and obese patients undergoing a lifestyle intervention program.

6.
Front Immunol ; 9: 1832, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30154787

RESUMO

Aging results in chronic systemic inflammation that can alter neuroinflammation of the brain. Specifically, microglia shift to a pro-inflammatory phenotype predisposing them to hyperactivation upon stimulation by peripheral immune signals. It is proposed that certain nutrients can delay brain aging by preventing or reversing microglial hyperactivation. Butyrate, a short-chain fatty acid (SCFA) produced primarily by bacterial fermentation of fiber in the colon, has been extensively studied pharmacologically as a histone deacetylase inhibitor and serves as an attractive therapeutic candidate, as butyrate has also been shown to be anti-inflammatory and improve memory in animal models. In this study, we demonstrate that butyrate can attenuate pro-inflammatory cytokine expression in microglia in aged mice. It is still not fully understood, however, if an increase in butyrate-producing bacteria in the gut as a consequence of a diet high in soluble fiber could affect microglial activation during aging. Adult and aged mice were fed either a 1% cellulose (low fiber) or 5% inulin (high fiber) diet for 4 weeks. Findings indicate that mice fed inulin had an altered gut microbiome and increased butyrate, acetate, and total SCFA production. In addition, histological scoring of the distal colon demonstrated that aged animals on the low fiber diet had increased inflammatory infiltrate that was significantly reduced in animals consuming the high fiber diet. Furthermore, gene expression of inflammatory markers, epigenetic regulators, and the microglial sensory apparatus (i.e., the sensome) were altered by both diet and age, with aged animals exhibiting a more anti-inflammatory microglial profile on the high fiber diet. Taken together, high fiber supplementation in aging is a non-invasive strategy to increase butyrate levels, and these data suggest that an increase in butyrate through added soluble fiber such as inulin could counterbalance the age-related microbiota dysbiosis, potentially leading to neurological benefits.

7.
J Physiol ; 596(14): 2811-2822, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29923191

RESUMO

KEY POINTS: Chronic inflammation underlies many of the health decrements associated with obesity. Circulating progenitor cells can sense and respond to inflammatory stimuli, increasing the local inflammatory response within tissues. Here we show that 6 weeks of endurance exercise training significantly decreases inflammatory circulating progenitor cells in obese adults. These findings provide novel cellular mechanisms for the beneficial effects of exercise in obese adults. ABSTRACT: Circulating progenitor cells (CPCs) and subpopulations are normally found in the bone marrow, but can migrate to peripheral tissues to participate in local inflammation and/or remodelling. The purpose of this study was to compare the CPC response, particularly the inflammatory-primed haematopoietic stem and progenitor (HSPC) subpopulation, to a 6 week endurance exercise training (EET) intervention between lean and obese adults. Seventeen healthy weight (age: 23.9 ± 5.4 years, body mass index (BMI): 22.0 ± 2.6 kg m-2 ) and 10 obese (age: 29.0 ± 8.0 years, BMI: 33.1 ± 6.0 kg m-2 ) previously sedentary adults participated in an EET. Blood was collected before and after EET for quantification of CPCs and subpopulations via flow cytometry, colony forming unit assays and plasma concentrations of C-X-C motif chemokine 12 (CXCL12), granulocyte-colony stimulating factor (G-CSF), and chemokine (C-C motif) ligand 2 (CCL2). Exercise training reduced the number of circulating HSPCs and adipose tissue-derived mesenchymal stem cells (AT-MSCs). EET increased the colony forming potential of granulocytes and macrophages irrespective of BMI. EET reduced the number of HSPCs expressing the chemokine receptor CCR2 and the pro-inflammatory marker TLR4. EET-induced changes in adipose tissue-derived MSCs and bone marrow-derived MSCs were negatively related to changes in absolute fitness. Our results indicate that EET, regardless of BMI status, decreases CPCs and subpopulations, particularly those primed for contribution to tissue inflammation.

8.
Med Sci Sports Exerc ; 50(4): 747-757, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29166320

RESUMO

PURPOSE: Exercise is associated with altered gut microbial composition, but studies have not investigated whether the gut microbiota and associated metabolites are modulated by exercise training in humans. We explored the impact of 6 wk of endurance exercise on the composition, functional capacity, and metabolic output of the gut microbiota in lean and obese adults with multiple-day dietary controls before outcome variable collection. METHODS: Thirty-two lean (n = 18 [9 female]) and obese (n = 14 [11 female]), previously sedentary subjects participated in 6 wk of supervised, endurance-based exercise training (3 d·wk) that progressed from 30 to 60 min·d and from moderate (60% of HR reserve) to vigorous intensity (75% HR reserve). Subsequently, participants returned to a sedentary lifestyle activity for a 6-wk washout period. Fecal samples were collected before and after 6 wk of exercise, as well as after the sedentary washout period, with 3-d dietary controls in place before each collection. RESULTS: ß-diversity analysis revealed that exercise-induced alterations of the gut microbiota were dependent on obesity status. Exercise increased fecal concentrations of short-chain fatty acids in lean, but not obese, participants. Exercise-induced shifts in metabolic output of the microbiota paralleled changes in bacterial genes and taxa capable of short-chain fatty acid production. Lastly, exercise-induced changes in the microbiota were largely reversed once exercise training ceased. CONCLUSION: These findings suggest that exercise training induces compositional and functional changes in the human gut microbiota that are dependent on obesity status, independent of diet and contingent on the sustainment of exercise.

9.
Exp Gerontol ; 98: 22-29, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28818411

RESUMO

We have previously shown that 6weeks of a diet containing epigallocatechin gallate (EGCG) and beta-alanine (B-ALA) was not effective in improving either cognitive or muscle function in aged (18month) mice (Gibbons et al. Behav Brain Res 2014). However, diet reduced oxidative stress in the brain, and previous studies using longer-term interventions have documented beneficial effects in cognitive, but not muscle, function. Therefore, we investigated the effect of 6months of feeding on measures of cognitive and muscle function in mice. Mice (12months, N=15/group) were fed AIN-93M containing 0.15% EGCG and 0.34% B-ALA or standard AIN-93M for 6months, then underwent a battery of tests for cognitive and muscle function at 18months. Interestingly, a higher percentage of mice receiving EGCG and B-ALA (E+B, 80%) survived to study end compared to control (Ctrl, 40%) mice (p=0.02). E+B did not affect arm preference in the Y-maze test (p=0.74, novel arm) and did not alter performance in an active avoidance test (p=0.16, avoidances per 50 trials). E+B increased rotarod performance (p=0.03), did not affect grip strength (p=0.91), and decreased time to exhaustion in a treadmill fatigue test (p=0.02) compared to Ctrl. In conclusion, E+B reduced mortality, had no effect on cognitive function and variable effects on muscle function.


Assuntos
Comportamento Animal/efeitos dos fármacos , Catequina/análogos & derivados , Cognição/efeitos dos fármacos , Suplementos Nutricionais , Longevidade/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , beta-Alanina/administração & dosagem , Animais , Catequina/administração & dosagem , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Modelos Animais , Atividade Motora/efeitos dos fármacos , Músculo Esquelético/fisiologia , Resistência Física/efeitos dos fármacos , Teste de Desempenho do Rota-Rod , Fatores de Tempo
10.
Appl Physiol Nutr Metab ; 42(5): 495-502, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28177724

RESUMO

We have previously shown that a diet containing epigallocatechin gallate (EGCG) and beta-alanine is not effective in improving either cognitive or muscle function in aged (18 month) mice (Gibbons et al., Behav. Brain Res., 2014, 272:131-140; Pence et al., Appl. Physiol. Nutr. Metab., 2016, 41(2): 181-190). However, this diet reduced oxidative stress in the brain, and previous studies using longer term interventions and other doses have documented beneficial effects in cognitive and muscle function, especially with EGCG. Here we hypothesized that a different dose of EGCG or longer feeding period would be more efficacious in improving cognition. Aged (21-25 mo) Balb/cByJ male mice underwent 63 days of feeding with EGCG at 0, 0.091, or 3.67 mg/g AIN-93M diet and were then subjected to a battery of cognitive and muscle function tests. EGCG feeding at either of the 2 doses did not alter preference for novel versus familiar arm in the Y-maze test (p = 0.29) and did not affect learning in the active avoidance test (p = 0.76). Similarly, EGCG did not affect preference for novel versus familiar mice in a social discrimination test (p = 0.17). Likewise, there was no effect of EGCG on muscle function by grip strength (p = 0.16), rotarod (p = 0.18), or treadmill test to exhaustion (p = 0.25). EGCG reduced mortality in a dose-dependent fashion (p = 0.05, log-rank test for trend), with 91% of high EGCG, 72% of low EGCG, and 55% of control mice surviving to the end of the study. In conclusion, EGCG improves survival in aged mice but does not affect cognitive or muscle function.


Assuntos
Envelhecimento/efeitos dos fármacos , Catequina/análogos & derivados , Suplementos Nutricionais , Mortalidade , Ração Animal , Animais , Catequina/administração & dosagem , Catequina/farmacologia , Dieta/veterinária , Masculino , Camundongos , Distribuição Aleatória , Comportamento Social
11.
J Appl Physiol (1985) ; 122(2): 386-395, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-27979988

RESUMO

African Americans (AA) exhibit exaggerated central blood pressure (BP) and arterial stiffness measured by pulse wave velocity (PWV) in response to an acute bout of maximal exercise compared with Caucasians (CA). However, whether potential racial differences exist in central BP, elastic, or muscular arterial distensibility after submaximal aerobic exercise remains unknown. Histamine receptor activation mediates sustained postexercise hyperemia in CA but the effect on arterial stiffness is unknown. This study sought to determine the effects of an acute bout of aerobic exercise on central BP and arterial stiffness and the role of histamine receptors, in AA and CA. Forty-nine (22 AA, 27 CA) young and healthy subjects completed the study. Subjects were randomly assigned to take either histamine receptor antagonist or control placebo. Central blood BP and arterial stiffness measurements were obtained at baseline, and at 30, 60, and 90 min after 45 min of moderate treadmill exercise. AA exhibited greater central diastolic BP, elevated brachial PWV, and local carotid arterial stiffness after an acute bout of submaximal exercise compared with CA, which may contribute to their higher risk of cardiovascular disease. Unexpectedly, histamine receptor blockade did not affect central BP or PWV in AA or CA after exercise, but it may play a role in mediating local carotid arterial stiffness. Furthermore, histamine may mediate postexercise carotid arterial dilation in CA but not in AA. These observations provide evidence that young and healthy AA exhibit an exaggerated hemodynamic response to exercise and attenuated vasodilator response compared with CA.NEW & NOTEWORTHY African Americans are at greater risk for developing cardiovascular disease than Caucasians. We are the first to show that young and healthy African Americans exhibit greater central blood pressure, elevated brachial stiffness, and local carotid arterial stiffness following an acute bout of submaximal exercise compared with Caucasians, which may contribute to their higher risk of cardiovascular disease. Furthermore, African Americans exhibit attenuated vasodilator response compared with Caucasians.


Assuntos
Exercício/fisiologia , Antagonistas dos Receptores Histamínicos/farmacologia , Receptores Histamínicos/metabolismo , Rigidez Vascular/efeitos dos fármacos , Rigidez Vascular/fisiologia , Adulto , Afro-Americanos , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Determinação da Pressão Arterial/métodos , Artéria Braquial/efeitos dos fármacos , Artéria Braquial/fisiologia , Artérias Carótidas/efeitos dos fármacos , Artérias Carótidas/fisiologia , Grupo com Ancestrais do Continente Europeu , Teste de Esforço/métodos , Feminino , Hemodinâmica/efeitos dos fármacos , Hemodinâmica/fisiologia , Humanos , Hiperemia/tratamento farmacológico , Hiperemia/fisiopatologia , Masculino , Análise de Onda de Pulso/métodos , Adulto Jovem
12.
Front Physiol ; 8: 1123, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29354074

RESUMO

Exercise has been shown to improve immune responses to viral infections and vaccines in several mouse models. However, previous pathogen studies have primarily used infections limited to the respiratory tract. Additionally, previous studies have utilized forced treadmill exercise paradigms, and voluntary wheel running (VWR) has been shown to have differential effects on the immune system in non-infection models. We examined whether VWR could improve morbidity and mortality to a 50% lethal dose of vaccinia virus (VACV), a systemic pathogen commonly used to examine immune responses. Additionally, we examined whether VWR could improve antibody response to a replication-deficient strain of VACV, mimicking a vaccination. Male C57Bl/6J mice underwent 8 weeks of VWR or remained sedentary, then were infected intranasally with 105 PFU VACV strain WR and followed 14 days for weight loss. Mice in the vaccination study ran or were sedentary for 8 weeks, then were given 106 PFU of replication-deficient VACV strain MVA intraperitoneally. Blood was collected at 1, 2, and 4 weeks post-inoculation, and anti-VACV IgG titer was determined by ELISA. VWR did not improve mortality due to VACV infection (p = 0.26), although fewer VWR mice (4/10) died compared to sedentary (SED, 6/10). VWR did not prevent body weight loss due to infection compared to SED (p = 0.20), although VWR mice loss slightly less weight compared to SED through the first 6 days post-infection. Food intake was significantly reduced in SED post-infection compared to VWR (p = 0.05). VWR mice developed a greater IgG antibody response, although this was not significant (p = 0.22). In summary, VWR did not protect against mortality to VACV or prevent infection-induced weight loss, and VWR did not enhance antibody responses. However, there were non-significant trends toward VWR-related improvements in these outcomes, and post-infection food intake was improved by VWR.

13.
PLoS One ; 11(12): e0168065, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27936249

RESUMO

HMG-CoA reductase inhibitors (statins) are the most effective pharmacological means of reducing cardiovascular disease risk. The most common side effect of statin use is skeletal muscle myopathy, which may be exacerbated by exercise. Hypercholesterolemia and training status are factors that are rarely considered in the progression of myopathy. The purpose of this study was to determine the extent to which acute and chronic exercise can influence statin-induced myopathy in hypercholesterolemic (ApoE-/-) mice. Mice either received daily injections of saline or simvastatin (20 mg/kg) while: 1) remaining sedentary (Sed), 2) engaging in daily exercise for two weeks (novel, Nov), or 3) engaging in daily exercise for two weeks after a brief period of training (accustomed, Acct) (2x3 design, n = 60). Cholesterol, activity, strength, and indices of myofiber damage and atrophy were assessed. Running wheel activity declined in both exercise groups receiving statins (statin x time interaction, p<0.05). Cholesterol, grip strength, and maximal isometric force were significantly lower in all groups following statin treatment (statin main effect, p<0.05). Mitochondrial content and myofiber size were increased and 4-HNE was decreased by exercise (statin x exercise interaction, p<0.05), and these beneficial effects were abrogated by statin treatment. Exercise (Acct and Nov) increased atrogin-1 mRNA in combination with statin treatment, yet enhanced fiber damage or atrophy was not observed. The results from this study suggest that exercise (Nov, Acct) does not exacerbate statin-induced myopathy in ApoE-/- mice, yet statin treatment reduces activity in a manner that prevents muscle from mounting a beneficial adaptive response to training.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Músculo Esquelético/patologia , Doenças Musculares/induzido quimicamente , Condicionamento Físico Animal , Animais , Peso Corporal , Colesterol/sangue , Camundongos , Tamanho do Órgão
14.
Physiology (Bethesda) ; 31(5): 327-35, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27511459

RESUMO

Many factors are involved in weight gain and metabolic disturbances associated with obesity. The gut microbiota has been of particular interest in recent years, since both human and animal studies have increased our understanding of the delicate symbiosis between the trillions of microbes that reside in the GI tract and the host. It has been suggested that disruption of this mutual tolerance may play a significant role in modulating host physiology during obesity. Environmental influences such as diet, exercise, and early life exposures can significantly impact the composition of the microbiota, and this dysbiosis can in turn lead to increased host adiposity via a number of different mechanisms. The ability of the microbiota to regulate host fat deposition, metabolism, and immune function makes it an attractive target for achieving sustained weight loss.


Assuntos
Microbioma Gastrointestinal , Obesidade/microbiologia , Obesidade/fisiopatologia , Animais , Dieta , Metabolismo Energético , Homeostase , Humanos , Inflamação
15.
J Hypertens ; 34(12): 2402-2409, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27552645

RESUMO

BACKGROUND: Aging is characterized by a state of chronic, low-grade inflammation that impairs vascular function. Acute inflammation causes additional decrements in vascular function, but these responses are not uniform in older compared with younger adults. We sought to determine if older adults with low levels of baseline inflammation respond to acute inflammation in a manner similar to younger adults. We hypothesized age-related differences in the vascular responses to acute inflammation, but that older adults with low baseline inflammation would respond similarly to younger adults. METHOD: Inflammation was induced with an influenza vaccine in 96 participants [older = 67 total, 38 with baseline C-reactive protein (CRP) > 1.5 mg/l and 29 with CRP < 1.5 mg/l; younger = 29]; serum inflammatory markers IL-6 and CRP, blood pressure and flow-mediated dilation (FMD) were measured 24 and 48 h later. RESULTS: Younger adults increased IL-6 and CRP more than the collective older adult group and increased pulse pressure, whereas older adults decreased SBP and reduced pulse pressure. The entire cohort decreased FMD from 11.3 ±â€Š0.8 to 8.3 ±â€Š0.7 to 8.7 ±â€Š0.7% in younger and from 5.8 ±â€Š0.3 to 5.0 ±â€Š0.4 to 4.7 ±â€Š0.4% in older adults, P less than 0.05 for main effect. Older adult groups with differing baseline CRP had the same IL-6, blood pressure, and FMD response to acute inflammation, P less than 0.05 for all interactions, but the low-CRP group increased CRP at 24 and 48 h (from 0.5 ±â€Š0.1 to 1.4 ±â€Š0.2 to 1.7 ±â€Š0.3 mg/l), whereas the high-CRP group did not (from 4.8 ±â€Š0.5 to 5.4 ±â€Š0.5 to 5.4 ±â€Š0.6 mg/l), P less than 0.001 for interaction. CONCLUSION: Aging, not age-related chronic, low-grade inflammation, determines the vascular responses to acute inflammation.


Assuntos
Envelhecimento/fisiologia , Pressão Sanguínea , Endotélio Vascular/fisiopatologia , Inflamação/fisiopatologia , Adulto , Fatores Etários , Idoso , Proteína C-Reativa/metabolismo , Feminino , Frequência Cardíaca , Humanos , Inflamação/sangue , Vacinas contra Influenza , Interleucina-6/sangue , Masculino , Pessoa de Meia-Idade , Vasodilatação , Adulto Jovem
16.
J Neurosci Res ; 94(10): 907-14, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27312674

RESUMO

Previous research has examined the effects of exercise in experimental autoimmune encephalomyelitis (EAE), the animal model of multiple sclerosis. However, all previous studies have utilized a chronic model of EAE, with exercise delivered prior to or immediately after induction of EAE. To our knowledge, no study has examined the effects of exercise delivered during a remission period after initial disease onset in a relapsing-remitting model of EAE (RR-EAE). The current study examines the effects of both voluntary wheel running and forced treadmill exercise on clinical disability and hippocampal brain-derived neurotrophic factor (BDNF) in SJL mice with RR-EAE. The results demonstrate no significant effects of exercise delivered during remission after initial disease onset on clinical disability scores or levels of hippocampal BDNF in mice with RR-EAE. Furthermore, our results demonstrate no significant increase in citrate synthase activity in the gastrocnemius and soleus muscles of mice in the running wheel or treadmill conditions compared with the sedentary condition. These results suggest that the exercise stimuli might have been insufficient to elicit differences in clinical disability or hippocampal BDNF among treatment conditions. © 2016 Wiley Periodicals, Inc.


Assuntos
Modelos Animais de Doenças , Encefalomielite Autoimune Experimental/fisiopatologia , Condicionamento Físico Animal/fisiologia , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Citrato (si)-Sintase/metabolismo , Encefalomielite Autoimune Experimental/induzido quimicamente , Encefalomielite Autoimune Experimental/patologia , Teste de Esforço , Feminino , Adjuvante de Freund/toxicidade , Hipocampo/metabolismo , Camundongos , Atividade Motora/fisiologia , Esclerose Múltipla/induzido quimicamente , Esclerose Múltipla/patologia , Esclerose Múltipla/fisiopatologia , Músculos/patologia , Proteína Proteolipídica de Mielina/imunologia , Proteína Proteolipídica de Mielina/toxicidade , Tamanho do Órgão , Fragmentos de Peptídeos/imunologia , Fragmentos de Peptídeos/toxicidade , Distribuição Aleatória , Recidiva , Corrida/fisiologia , Medula Espinal/metabolismo , Medula Espinal/patologia
17.
PLoS One ; 11(4): e0153445, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27074034

RESUMO

Post-exercise hypotension (PEH) is widely observed in Caucasians (CA) and is associated with histamine receptors 1- and 2- (H1R and H2R) mediated post-exercise vasodilation. However, it appears that blacks (BL) may not exhibit PEH following aerobic exercise. Hence, this study sought to determine the extent to which BL develop PEH, and the contribution of histamine receptors to PEH (or lack thereof) in this population. Forty-nine (22 BL, 27 CA) young and healthy subjects completed the study. Subjects were randomly assigned to take either a combined H1R and H2R antagonist (fexofenadine and ranitidine) or a control placebo. Supine blood pressure (BP), cardiac output and peripheral vascular resistance measurements were obtained at baseline, as well as at 30 min, 60 min and 90 min after 45 min of treadmill exercise at 70% heart rate reserve. Exercise increased diastolic BP in young BL but not in CA. Post-exercise diastolic BP was also elevated in BL after exercise with histamine receptor blockade. Moreover, H1R and H2R blockade elicited differential responses in stroke volume between BL and CA at rest, and the difference remained following exercise. Our findings show differential BP responses following exercise in BL and CA, and a potential role of histamine receptors in mediating basal and post-exercise stroke volume in BL. The heightened BP and vascular responses to exercise stimulus is consistent with the greater CVD risk in BL.


Assuntos
Grupo com Ancestrais do Continente Africano , Pressão Sanguínea/fisiologia , Grupo com Ancestrais do Continente Europeu , Exercício/fisiologia , Frequência Cardíaca/fisiologia , Adolescente , Adulto , Pressão Sanguínea/efeitos dos fármacos , Método Duplo-Cego , Feminino , Frequência Cardíaca/efeitos dos fármacos , Antagonistas dos Receptores Histamínicos H1/farmacologia , Antagonistas dos Receptores Histamínicos H2/farmacologia , Humanos , Perna (Membro)/irrigação sanguínea , Masculino , Consumo de Oxigênio/efeitos dos fármacos , Consumo de Oxigênio/fisiologia , Ranitidina/farmacologia , Fluxo Sanguíneo Regional/efeitos dos fármacos , Fluxo Sanguíneo Regional/fisiologia , Terfenadina/análogos & derivados , Terfenadina/farmacologia , Resistência Vascular/efeitos dos fármacos , Resistência Vascular/fisiologia , Adulto Jovem
18.
Exp Physiol ; 101(7): 962-71, 2016 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-27027865

RESUMO

NEW FINDINGS: What is the central question of this study? Do older and younger adults have similar vascular endothelial and blood pressure responses to acute inflammation? Does physical activity affect these responses? What is the main finding and its importance? Older adults reduce blood pressure whereas younger adults reduce endothelial function during acute inflammation. Physical activity does not provide protection against these inflammation-induced changes. This is important because older adults regularly experience acute increases in systemic inflammation that may predispose older adults to cardiovascular events through dysregulation of blood pressure. Ageing is characterized by chronic, low-grade inflammation that is related to endothelial dysfunction and arterial stiffness. Physical activity can protect older adults (OAs) from cardiovascular dysfunction and increased inflammation. Acute inflammation causes transient endothelial dysfunction and arterial stiffening in younger adults (YAs), but may not have the same effect in OAs. We hypothesized that acute inflammation would increase blood pressure (BP) and endothelial impairment to a greater extent in OAs versus YAs, but that physical activity would be protective. We induced inflammation with an influenza vaccine in 22 OAs (55-75 years old) and 31 YAs (18-35 years old) and measured brachial flow-mediated dilatation (FMD), BP and serum inflammatory markers before vaccination and at 24 and 48 h afterwards. Physical activity data were collected using accelerometry. During inflammation, only OAs reduced systolic BP (from 120 ± 3 to 115 ± 2 to 115 ± 3 mmHg, P < 0.05), but only YAs reduced FMD (from 11.3 ± 0.7 to 8.5 ± 0.6 to 8.9 ± 0.6% in YAs and from 6.7 ± 0.6 to 5.3 ± 0.7 to 6.0 ± 0.6% in OAs, P < 0.05 for time and interaction effects). The entire cohort increased C-reactive protein (P < 0.05), but only YAs increased interleukin-6 (P < 0.05 for time × age group interaction). Physical activity was related to the percentage change in inflammation in OAs (r = -0.50, P < 0.05) but not to the change in arterial function in either group (P > 0.05 for all). We conclude that acute inflammation reduced FMD only in YAs and reduced BP only in OAs. Physical activity did not affect arterial function during acute inflammation. Clinicians should be aware that all OAs are vulnerable to inflammation-mediated reductions in BP and cardiovascular complications.


Assuntos
Envelhecimento/fisiologia , Pressão Sanguínea/fisiologia , Endotélio Vascular/fisiopatologia , Exercício/fisiologia , Inflamação/fisiopatologia , Adulto , Fatores Etários , Proteína C-Reativa/metabolismo , Feminino , Humanos , Inflamação/induzido quimicamente , Mediadores da Inflamação/metabolismo , Vacinas contra Influenza/efeitos adversos , Interleucina-6/metabolismo , Masculino , Pessoa de Meia-Idade , Doenças Vasculares/metabolismo , Doenças Vasculares/fisiopatologia , Rigidez Vascular/fisiologia
19.
Appl Physiol Nutr Metab ; 41(2): 181-90, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26761622

RESUMO

Aging leads to sarcopenia and loss of physical function. We examined whether voluntary wheel running, when combined with dietary supplementation with (-)-epigallocatechin-3-gallate (EGCG) and ß-alanine (ß-ALA), could improve muscle function and alter gene expression in the gastrocnemius of aged mice. Seventeen-month-old BALB/cByJ mice were given access to a running wheel or remained sedentary for 41 days while receiving either AIN-93M (standard feed) or AIN-93M containing 1.5 mg·kg(-1) EGCG and 3.43 mg·kg(-1) ß-ALA. Mice underwent tests over 11 days from day 29 to day 39 of the study period, including muscle function testing (grip strength, treadmill exhaustive fatigue, rotarod). Following a rest day, mice were euthanized and gastrocnemii were collected for analysis of gene expression by quantitative PCR. Voluntary wheel running (VWR) improved rotarod and treadmill exhaustive fatigue performance and maintained grip strength in aged mice, while dietary intervention had no effect. VWR increased gastrocnemius expression of several genes, including those encoding interleukin-6 (Il6, p = 0.001), superoxide dismutase 1 (Sod1, p = 0.046), peroxisome proliferator-activated receptor gamma coactivator 1-α (Ppargc1a, p = 0.013), forkhead box protein O3 (Foxo3, p = 0.005), and brain-derived neurotrophic factor (Bdnf, p = 0.008), while reducing gastrocnemius levels of the lipid peroxidation marker 4-hydroxynonenal (p = 0.019). Dietary intervention alone increased gastrocnemius expression of Ppargc1a (p = 0.033) and genes encoding NAD-dependent protein deacetylase sirtuin-1 (Sirt1, p = 0.039), insulin-like growth factor I (Igf1, p = 0.003), and macrophage marker CD11b (Itgam, p = 0.016). Exercise and a diet containing ß-ALA and EGCG differentially regulated gene expression in the gastrocnemius of aged mice, while VWR but not dietary intervention improved muscle function. We found no synergistic effects between dietary intervention and VWR.


Assuntos
Catequina/análogos & derivados , Suplementos Nutricionais , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/fisiologia , Corrida/fisiologia , beta-Alanina/farmacologia , Fatores Etários , Animais , Catequina/administração & dosagem , Catequina/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , beta-Alanina/administração & dosagem
20.
Immunol Cell Biol ; 94(2): 158-63, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26626721

RESUMO

There is robust evidence that habitual physical activity is anti-inflammatory and protective against developing chronic inflammatory disease. Much less is known about the effects of habitual moderate exercise in the gut, the compartment that has the greatest immunological responsibility and interactions with the intestinal microbiota. The link between the two has become evident, as recent studies have linked intestinal dysbiosis, or the disproportionate balance of beneficial to pathogenic microbes, with increased inflammatory disease susceptibility. Limited animal and human research findings imply that exercise may have a beneficial role in preventing and ameliorating such diseases by having an effect on gut immune function and, recently, microbiome characteristics. Emerging data from our laboratory show that different forms of exercise training differentially impact the severity of intestinal inflammation during an inflammatory insult (for example, ulcerative colitis) and may be jointly related to gut immune cell homeostasis and microbiota-immune interactions. The evidence we review and present will provide data in support of rigorous investigations concerning the effects of habitual exercise on gut health and disease.


Assuntos
Colite/imunologia , Colo/imunologia , Exercício/fisiologia , Intestinos/imunologia , Microbiota/imunologia , Animais , Colite/terapia , Colo/microbiologia , Terapia por Exercício , Homeostase , Humanos , Imunidade nas Mucosas/imunologia , Intestinos/microbiologia
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