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1.
Br J Nutr ; 132(3): 298-308, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-38826085

RESUMO

Marathon runners, subjected to intense training regimens and prolonged, exhaustive exercises, often experience a compromised immune response. Probiotic supplementation has emerged as a potential remedy to mitigate the impact of prolonged exercise on athletes. Consequently, this study sought to assess the influence of probiotic supplementation on monocyte functionality both before and after the official marathon race. Twenty-seven runners were randomly and double-blindly assigned to two groups: placebo (n 13) and probiotic (PRO) (n 14). Over 30 d, both groups received supplements - placebo sachets containing maltodextrin (5 g/d) and PRO sachets containing 1 × 1010 colony-forming unit Lactobacillus acidophilus and 1 × 1010 colony-forming unit Bifidobacterium bifidum subsp. lactis. Blood samples were collected, and immunological assays, including phagocytosis, hydrogen peroxide production, cytokine levels and monocyte immunophenotyping, were conducted at four different intervals: baseline (start of supplementation/30 d pre-marathon), 24 h-before (1 d pre-marathon), 1 h-after (1 h post-marathon) and 5 d-after (5 d post-marathon). Monocyte populations remained consistent throughout the study. A notable increase in phagocytosis was observed in the PRO group after 30 d of supplementation. Upon lipopolysaccharide stimulation, both PRO and placebo groups exhibited decreased IL-8 production. However, after the marathon race, IL-15 stimulation demonstrated increased levels of 5 d-after, while IL-1-ß, IL-8, IL-10, IL-15 and TNF-α varied across different intervals, specifically within the PRO group. Probiotic supplementation notably enhanced the phagocytic capacity of monocytes. However, these effects were not sustained post-marathon.


Assuntos
Suplementos Nutricionais , Corrida de Maratona , Monócitos , Fagocitose , Probióticos , Humanos , Fagocitose/efeitos dos fármacos , Probióticos/administração & dosagem , Probióticos/farmacologia , Monócitos/metabolismo , Monócitos/imunologia , Método Duplo-Cego , Masculino , Adulto , Corrida de Maratona/fisiologia , Citocinas/metabolismo , Citocinas/sangue , Feminino , Lactobacillus acidophilus , Bifidobacterium bifidum/fisiologia , Pessoa de Meia-Idade , Corrida/fisiologia , Atletas
2.
Front Sports Act Living ; 4: 915343, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36060625

RESUMO

Purpose: To investigate the effects of triathlon racing under extreme conditions on metabolic and immune/inflammatory responses. Methods: Thirteen amateur athletes participated in an extreme triathlon competition (swim - 3.8 km; cycling - 180 km; running - 4 2 km; with a 3,700 m accumulated altitude). Blood samples were collected on three different occasions: pre-competition (baseline), immediately post-competition (IM), and 12 h post-competition (12 h) to evaluate glycemic and lipid profiles, leukocytes count, and cytokines levels in plasma and in whole-blood cell culture supernatant stimulated or not with LPS. Results: Decreased glucose and triglycerides levels, increased LDL, and a significant leukocytosis were observed at IM and 12 h compared to baseline. In addition, higher serum levels of IL-6, IL-8, and IL-10 were found at IM than in baseline and post-12 h. Whereas increased IL-12p40 levels were observed for 12 h compared to baseline. At baseline, in LPS-stimulated cell culture, IL-6, IL-8, and IL-12p70 were higher, while IL-12p40 levels were lower than non-stimulated cell culture. At IM, IL-12p40 levels were unchanged, while higher levels of other cytokines were found in LPS-stimulated cell culture compared to non-stimulated cell culture. The 12 h results showed higher levels of IL-6, IL-8, and IL-10 in LPS-stimulated cell culture than in non-stimulated cell culture. Additionally, a significant negative correlation between circulating glucose levels and IL-6 was found. Conclusion: The triathlon competition's performance under extreme conditions has remarkable impacts on the lipid profile and systemic immune/inflammatory responses. For the first time, significant alterations in the cytokine responses of whole blood cell culture to LPS-stimulation in baseline, IM, and 12h were demonstrated.

3.
Artigo em Inglês | MEDLINE | ID: mdl-34639516

RESUMO

BACKGROUND: This study aimed to globally assess heat strain, dehydration, and mechanical load as acute kidney injury (AKI) indicators in amateur endurance trail athletes during a 35.3 km run. METHODS: Thirty amateur experienced trail runners completed an endurance trail run (total positive ascend 1815 m). The following assessments were performed at four measurement time points (pre-, during, immediately post [-post0h], and after 24 h of the finish of the run [-post24h]): serum test (creatinine, blood ureic nitrogen, albumin, creatine kinase, blood ureic nitrogen: creatinine ratio, creatinine clearance, and glomerular filtration rate), mechanical load (impacts and Player Load), heat strain and dehydration (hematocrit, urine solids, body weight and urine specific gravity), pain and exertion perception (rate of perceived exertion, lumbar and bipodal, and one-leg squat pain), and urinalysis (pH, protein, glucose, erythrocytes, and urine specific gravity). RESULTS: There were pre vs. post0h changes in all serum biomarkers (F = 5.4-34.45, p < 0.01). The change in these biomarkers correlated with an increase in mechanical load indicators (r = 0.47-59, p < 0.05). A total of 40% and 23.4% of participants presented proteinuria and hematuria, respectively. Pain and perceived exertion increased significantly due to effort made during the endurance trail running (F = 4.2-176.4, p < 0.01). CONCLUSIONS: Endurance trail running may lead to an increase in blood and urine indicators of transitional AKI. The difference in blood and urine markers was significantly related to the mechanical load during running, suggesting potential kidney overload and cumulative mechanical load.


Assuntos
Injúria Renal Aguda , Temperatura Alta , Injúria Renal Aguda/etiologia , Creatinina , Desidratação , Humanos , Pacientes Ambulatoriais , Resistência Física
4.
PeerJ ; 9: e10500, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33859869

RESUMO

BACKGROUND: Physical exercise is a health promotion factor regulating gene expression and causing changes in phenotype, varying according to exercise type and intensity. Acute strenuous exercise in sedentary individuals appears to induce different transcriptional networks in response to stress caused by exercise. The objective of this research was to investigate the transcriptional profile of strenuous experimental exercise. METHODOLOGY: RNA-Seq was performed with Rattus norvegicus soleus muscle, submitted to strenuous physical exercise on a treadmill with an initial velocity of 0.5 km/h and increments of 0.2 km/h at every 3 min until animal exhaustion. Twenty four hours post-physical exercise, RNA-seq protocols were performed with coverage of 30 million reads per sample, 100 pb read length, paired-end, with a list of counts totaling 12816 genes. RESULTS: Eighty differentially expressed genes (61 down-regulated and 19 up-regulated) were obtained. Reactome and KEGG database searches revealed the most significant pathways, for down-regulated gene set, were: PI3K-Akt signaling pathway, RAF-MAP kinase, P2Y receptors and Signaling by Erbb2. Results suggest PI3K-AKT pathway inactivation by Hbegf, Fgf1 and Fgr3 receptor regulation, leading to inhibition of cell proliferation and increased apoptosis. Cell signaling transcription networks were found in transcriptome. Results suggest some metabolic pathways which indicate the conditioning situation of strenuous exercise induced genes encoding apoptotic and autophagy factors, indicating cellular stress. CONCLUSION: Down-regulated networks showed cell transduction and signaling pathways, with possible inhibition of cellular proliferation and cell degeneration. These findings reveal transitory and dynamic process in cell signaling transcription networks in skeletal muscle after acute strenuous exercise.

5.
Nutrients ; 13(5)2021 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-33925633

RESUMO

(1) Purpose: Performing strenuous exercises negatively impacts the immune and gastrointestinal systems. These alterations cause transient immunodepression, increasing the risk of minor infections, especially in the upper respiratory tract. Recent studies have shown that supplementation of probiotics confers benefits to athletes. Therefore, the objective of the current study was to verify the effects of probiotic supplementation on cytokine production by monocytes and infections in the upper respiratory tract after an acute strenuous exercise. (2) Methods: Fourteen healthy male marathon runners received either 5 billion colony forming units (CFU) of a multi-strain probiotic, consisting of 1 billion CFU of each of Lactobacillus acidophilus LB-G80, Lactobacillus paracasei LPc-G110, Lactococcus subp. lactis LLL-G25, Bifidobacterium animalis subp. lactis BL-G101, and Bifidobacterium bifidum BB-G90, or a placebo for 30 days before a marathon. Plasma cytokines, salivary parameters, glucose, and glutamine were measured at baseline, 24 h before, immediately after, and 1 h after the race. Subjects self-reported upper respiratory tract infection (URTI) using the Wisconsin Upper Respiratory Symptom Survey (WURSS-21). The statistical analyses comprised the general linear model (GLM) test followed by the Tukey post hoc and Student's t-test with p < 0.05. (3) Results: URTI symptoms were significantly lower in the probiotic group compared to placebo. The IL-2 and IL-4 plasma cytokines were lower 24 h before exercise, while the other cytokines showed no significant differences. A lower level of IL-6 produced by monocytes was verified immediately after the race and higher IL-10 at 1 h post. No differences were observed in salivary parameters. Conclusion: Despite the low number of marathoners participating in the study, probiotic supplementation suggests its capability to preserve the functionality of monocytes and mitigate the incidence of URTI.


Assuntos
Atletas/estatística & dados numéricos , Citocinas/sangue , Corrida de Maratona , Monócitos/metabolismo , Probióticos/farmacologia , Infecções Respiratórias/prevenção & controle , Adulto , Citocinas/efeitos dos fármacos , Citocinas/imunologia , Método Duplo-Cego , Humanos , Masculino , Monócitos/efeitos dos fármacos , Monócitos/imunologia , Infecções Respiratórias/imunologia
6.
Nutrition ; 54: 158-164, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29982143

RESUMO

OBJECTIVE: The aim of this study was to investigate the regulatory effects of taurine on the biochemical parameters of muscle injury by overuse. METHODS: Male Swiss mice were divided into four groups: control (Ctrl), overuse (Ov), taurine (Tau), and overuse plus taurine (OvTau). High-intensity exercise sessions were administered for 21 d with concomitant subcutaneous injections of taurine (150 mg/kg). The mice were then sacrificed. The quadriceps muscles were surgically removed for subsequent histologic analysis and evaluation of mitochondrial function, oxidative stress parameters, tissue repair, and DNA damage markers. RESULTS: The Ov group showed significant differences compared with the Ctrl group (all P <0.05). The fiber area decreased by 49.34%, whereas the centralized nuclei contents (Ctrl = 1.33%; Ov = 28.67%), membrane potential (Ctrlsuc = 179.05 arbitrary fluorescence units (AFUs), Ctrlsuc+ADP = 198.11 AFUs; Ovsuc = 482.95 AFUs, Ovsuc+ADP = 461.6 AFUs), complex I activity (Ctrl = 20.45 nmol ⋅ min ⋅ mg protein, Ov = 45.25 nmol ⋅ min ⋅ mg protein), hydrogen peroxide (Ctrlsuc = 1.08 relative fluorescence unit (RFU) ⋅ sec ⋅ mg protein, Ctrlsuc+ADP = 0.23 RFU ⋅ sec ⋅ mg protein; Ovsuc = 5.02 RFU ⋅ sec ⋅ mg protein, Ovsuc+ADP = 0.26 RFU ⋅ sec ⋅ mg protein) and malondialdehyde (Ctrl = 0.03 nmol ⋅ mg ⋅ protein, Ov = 0.06 nmol ⋅ mg ⋅ protein) levels, and DNA damage (Ctrlfreq = 7.17%, Ovfreq = 31.17%; Ctrlindex = 4.17, Ovindex = 72.5) were increased. Taurine administration reduced the number of centralized nuclei (OvTau = 5%), hydrogen peroxide levels (OvTausuc = 2.81 RFU ⋅ sec ⋅ mg protein, OvTaussuc+ADP = 1.54 RFU ⋅ sec ⋅ mg protein), membrane potential (OvTausuc = 220.18 AFUs, OvTaussuc+ADP = 235.28 AFUs), lipid peroxidation (OvTau = 0.02 nmol/mg protein), and DNA damage (OvTaufreq = 21.33%, OvTauindex = 47.83) and increased the fiber area by 54% (all P <0.05). CONCLUSION: Taken together, these data suggest that taurine supplementation modulates various cellular remodeling parameters after overuse-induced muscle damage, and that these positive effects may be related to its antioxidant capacity.


Assuntos
Antioxidantes/farmacologia , Transtornos Traumáticos Cumulativos/tratamento farmacológico , Músculo Esquelético/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Taurina/farmacologia , Animais , Transtornos Traumáticos Cumulativos/fisiopatologia , Modelos Animais de Doenças , Masculino , Camundongos , Mitocôndrias/efeitos dos fármacos , Condicionamento Físico Animal/fisiologia
7.
Int J Exerc Sci ; 10(8): 1165-1173, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29399246

RESUMO

The aim of the study was to determine the acute systolic (SBP) and diastolic (DBP) blood pressure, rating of perceived exertion (RPE) and heart rate (HR) responses following two intense training sessions (24 hours apart). Nine male extreme conditioning program (ECP) practitioners with more than 6 months of experience (age 26.7 ± 6.6 years; body mass 78.8 ± 13.2 kg; body fat 13.5 ± 6.2 %) completed two experimental ECP sessions. Cardiovascular variables were measured before, immediately after and every 15 min during a 45 min recovery following each experimental session. Compared with pre-exercise data, our results showed a SBP decrease at 30 min post exercise session 1 (P≤0.05) and at 45 min following exercise session 2. DBP decreased (P≤0.05) at 15 min and 30 min following exercise session 1 and at 30 min after the exercise session 2, respectively. HR remained significantly higher (P≤0.05) 45 min following the first and second exercise session compared with pre-exercise values. Exercise session 1 induced a higher increase in HR (86 ± 11% of HRmax versus 82 ± 12% of HRmax, p = 0.01) and RPE (8.8 ± 1.2 versus 8.0 ± 1.2, p = 0.02) when compared to exercise session 2. In conclusion, post-exercise hypotension occurs following strenuous exercise sessions, regardless of the session design, which may have an important role in the prevention of cardiovascular diseases.

8.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;47(6): 492-498, 06/2014. tab, graf
Artigo em Inglês | LILACS | ID: lil-709444

RESUMO

The effect of an adventure sprint race (ASR) on T-cell proliferation, leukocyte count and muscle damage was evaluated. Seven young male runners completed an ASR in the region of Serra do Espinhaço, Brazil. The race induced a strong leukocytosis (6.22±2.04×103 cells/mm3 before vs 14.81±3.53×103 cells/mm3 after the race), marked by a significant increase of neutrophils and monocytes (P<0.05), but not total lymphocytes, CD3+CD4+ or CD3+CD8+ cells. However, the T-cell proliferative response to mitogenic stimulation was increased (P=0.025) after the race, which contradicted our hypothesis that ASR, as a high-demand competition, would inhibit T-cell proliferation. A positive correlation (P=0.03, r=0.79) was observed between the proliferative response of lymphocytes after the race and the time to complete the race, suggesting that the proliferative response was dependent on exercise intensity. Muscle damage was evident after the race by increased serum levels of aspartate amino transferase (24.99±8.30 vs 50.61±15.76 U/L, P=0.003). The results suggest that humoral factors and substances released by damaged muscle may be responsible for lymphocyte activation, which may be involved in muscle recovery and repair.


Assuntos
Adulto , Humanos , Masculino , Proliferação de Células/fisiologia , Leucocitose/imunologia , Músculo Esquelético/lesões , Resistência Física/imunologia , Corrida/lesões , Linfócitos T/imunologia , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Citometria de Fluxo , Terapia de Imunossupressão , Contagem de Leucócitos , Leucocitose/etiologia , Monócitos/imunologia , Músculo Esquelético/imunologia , Neutrófilos/imunologia , Resistência Física/fisiologia , Corrida/fisiologia , Linfócitos T Citotóxicos/fisiologia , Linfócitos T Auxiliares-Indutores/fisiologia , Fatores de Tempo
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