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1.
Brain Behav Immun ; 75: 251-257, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30790541

RESUMO

Apoptosis is a genetically regulated form of programmed cell death which promotes the elimination of potentially detrimental immune cells. However, exercise-associated apoptosis is thought to induce a temporarily decline of the adaptive immune competence in the early post-exercise period. The purpose of the present study was to investigate if the aerobic endurance training status affects the sensitivity of human peripheral blood lymphocytes towards different types of apoptosis inducers and secondly, if this is mediated by the modulation of apoptosis-associated proteins and microRNAs. Collected at resting conditions, isolated lymphocytes of endurance trained athletes (ET) and healthy untrained subjects were either exposed to phytohemagglutinin-L (PHA-L), hydrogen peroxide (H2O2), or dexamethasone (DEX) as apoptosis inducer. Results revealed no significant differences between ET and UT in terms of lymphocyte apoptosis immediately following isolation as determined by flow cytometry using annexin V staining. After 24 h of ex vivo cultivation, lymphocytes of ET showed a reduced sensitivity to PHA-L-induced lymphocyte apoptosis which was accompanied by a noticeably up-regulation of the prominent apoptosis inhibitor genes X-linked inhibitor of apoptosis (XIAP) and Cyclin dependent kinase inhibitor 1B (CDKN1B) as analyzed by quantitative real-time PCR. Moreover, a trend was observed for the suppression of the corresponding pro-apoptotic miR-221. Lymphocyte apoptosis in control, H2O2 and DEX treated cells was not affected by aerobic endurance training status. However, distinct molecular signatures could be identified in un-treated control samples characterized by a counterbalanced modulation of pro- and anti-apoptotic mediators in ET. The results of the current study suggest that lymphocytes adapt to repetitive endurance exercise training by promoting lymphocyte homeostasis and increasing their resistance to apoptosis. This could be based on an up-regulation of anti-apoptotic proteins and a reduction in pro-apoptotic microRNAs which together tightly regulate the genetically defined apoptotic pathways governed by the type of apoptosis stimuli. Thus, the lymphocytes of endurance-trained athletes may be primed to counteract the transient immune suppression post-exercise.


Assuntos
Apoptose/fisiologia , Exercício Físico/fisiologia , Linfócitos/fisiologia , Adaptação Fisiológica , Adulto , Atletas , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Dexametasona/farmacologia , Treino Aeróbico/métodos , Regulação da Expressão Gênica/fisiologia , Humanos , Peróxido de Hidrogênio/farmacologia , Linfócitos/metabolismo , Masculino , MicroRNAs/metabolismo , MicroRNAs/fisiologia , Fito-Hemaglutininas/farmacologia , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/metabolismo
2.
J Med Genet ; 54(4): 248-253, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27651446

RESUMO

BACKGROUND: It has been proposed that cancer is more common in some families than in others, but the hypothesis lacks population level support. We use a novel approach by studying any cancers in large three-generation families and thus are able to find risks even though penetrance is low. METHODS: Individuals in the nation-wide Swedish Family-Cancer Database were organised in three generations and the relative risk (RR) of cancer was calculated to the persons in the third generation by the numbers of patients with cancer in generations 1, 2 and 3. RESULTS: The RRs for any cancer in generation 3 increased by the numbers of affected relatives, reaching 1.61 when at least seven relatives were diagnosed. The median patient had two affected relatives, and 7.0% had five or more affected relatives with an RR of 1.46, which translated to an absolute risk of 21.5% compared with 14.7% in population by age 65 years. For prostate cancer, the RR was 2.85 with four or more affected family members with any cancer, and it increased to 14.42 with four or more concordant cancers in family members. RRs for prostate cancer were approximately equal (2.70 vs 2.85) if a man had one relative with prostate cancer or four or more relatives diagnosed with any cancer. CONCLUSIONS: A strong family history of cancer, regardless of tumour type, increases cancer risk of family members and calls for mechanistic explanations. Our data provide tools for counselling of patients with cancer with both low and high familiar risks.


Assuntos
Neoplasias da Mama/genética , Predisposição Genética para Doença , Neoplasias da Próstata/genética , Adulto , Idoso , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/patologia , Família , Feminino , Aconselhamento Genético , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/patologia , Fatores de Risco , Suécia/epidemiologia
3.
Int J Cancer ; 140(7): 1510-1516, 2017 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-28006863

RESUMO

Relatives of cancer patients are at an increased risk of the same (concordant) cancer but whether they are at a risk for different (discordant) cancers is largely unknown - beyond well characterized hereditary cancer syndromes - but would be of major scientific and clinical interest. We therefore decided to resolve the issue by analyzing familial risks when family members were diagnosed with any discordant cancers. We compared the population impact of concordant to discordant familial cancer. The Swedish Family-Cancer Database (FCD) was used to calculate familial relative risks (RRs) for family members of cancer patients, for the 27 most common cancers. Population attributable fractions (PAFs) were estimated for concordant and discordant family histories. Discordant cancers in the family were detected as significant risk factors for the majority of cancers, although the corresponding RRs were modest compared to RRs for concordant cancers. Risks increased with the number of affected family members with the highest RRs for pancreatic (2.31), lung (1.69), kidney (1.98), nervous system (1.79) and thyroid cancers (3.28), when 5 or more family members were diagnosed with discordant cancers. For most cancers, the PAF for discordant family history exceeded that for concordant family history. Our findings suggest that there is an unspecific genetic predisposition to cancer with clinical consequences. We consider it unlikely that shared environmental risk factors could essentially contribute to the risks for diverse discordant cancers, which are likely driven by genetic predisposition. The identification of genes that moderately increase the risk for many cancers will be a challenge.


Assuntos
Neoplasias/epidemiologia , Neoplasias/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Bases de Dados Factuais , Saúde da Família , Feminino , Predisposição Genética para Doença , Humanos , Neoplasias Renais/genética , Neoplasias Pulmonares/genética , Masculino , Pessoa de Meia-Idade , Neoplasias/diagnóstico , Neoplasias do Sistema Nervoso/genética , Neoplasias Pancreáticas/genética , Sistema de Registros , Fatores de Risco , Suécia , Neoplasias da Glândula Tireoide/genética
4.
Eur J Appl Physiol ; 117(3): 591-605, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28224232

RESUMO

PURPOSE: The purpose of this double-blind, randomized, placebo-controlled clinical trial was to investigate the effects of the natural combination medicine Traumeel (Tr14) consisting of 14 diluted biological and mineral components on the inflammatory immune response and recovery up to 72 h after repetitive bouts of bicycle tests. METHODS: Antigen-stimulated IL-1ra and IL-6 were defined as primary outcome measures. Moreover, various immunological and serum muscle damage markers were investigated. The evaluation was performed using the score of the area under the curve with respect to increase (AUCi) for 24 and 72 h after the second exercise test (EX2). RESULTS: The Tr14 group indicated a lower decrease of lymphocytes by tendency (p = 0.06) and a lower activation of lymphocyte activation markers (CD62L absolute: p = 0.04; CD69: p = 0.01 and CD69 absolute: p = 0.05) in the period 24 h after EX2. In addition, the Tr14 group indicated a higher expression of antigen-stimulated CCL3 (p = 0.01), CCL4 (p = 0.07) and serum CCL2 (p = 0.05) in the period 24 h after EX2. There was a tendentially lower decrease of monocytes (p = 0.09) and a lower expression of antigen-stimulated MMP-3 (p = 0.01) in the Tr14 group in the period 72 h after EX2. However, antigen-stimulated IL-1ra and IL-6 showed no group differences. CONCLUSION: In line with the previous results, it was shown that Tr14 attenuates the adaptive immune response partially. Furthermore, the results indicate that Tr14 is able to stimulate the innate immune system via an increased production of pro-inflammatory chemokines. It is speculated that the higher expression of chemokines might play a role in the regeneration and recovery after exercise.


Assuntos
Anti-Inflamatórios/farmacologia , Citocinas/sangue , Exercício Físico , Ativação Linfocitária/efeitos dos fármacos , Minerais/farmacologia , Extratos Vegetais/farmacologia , Adulto , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/efeitos adversos , Biomarcadores/sangue , Humanos , Masculino , Minerais/administração & dosagem , Minerais/efeitos adversos , Extratos Vegetais/administração & dosagem , Extratos Vegetais/efeitos adversos
5.
Int J Cancer ; 139(1): 75-84, 2016 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-26875008

RESUMO

Despite advances in targeted therapies, the treatment of advanced melanoma remains an exercise in disease management, hence a need for biomarkers for identification of at-risk primary melanoma patients. In this study, we aimed to assess the prognostic value of TERT promoter mutations in primary melanomas. Tumors from 300 patients with stage I/II melanoma were sequenced for TERT promoter and BRAF/NRAS mutations. Cumulative curves were drawn for patients with and without mutations with progression-free and melanoma-specific survival as outcomes. Cox proportional hazard regression models were used to determine the effect of the mutations on survivals. Individually, presence of TERT promoter and BRAF/NRAS mutations associated with poor disease-free and melanoma-specific survival with modification of the effect by the rs2853669 polymorphism within the TERT promoter. Hazard ratio (HR) for simultaneous occurrence of TERT promoter and BRAF/NRAS mutations for disease-free survival was 2.3 (95% CI 1.2-4.4) and for melanoma-specific survival 5.8 (95% CI 1.9-18.3). The effect of the mutations on melanoma-specific survival in noncarriers of variant allele of the polymorphism was significant (HR 4.5, 95% CI 1.4-15.2) but could not be calculated for the carriers due to low number of events. The variant allele per se showed association with increased survival (HR 0.3, 95% CI 0.1-0.9). The data in this study provide preliminary evidence that TERT promoter mutations in combination with BRAF/NRAS mutations can be used to identify patients at risk of aggressive disease and the possibility of refinement of the classification with inclusion of the rs2853669 polymorphism within TERT promoter.


Assuntos
Biomarcadores Tumorais/genética , Melanoma/genética , Prognóstico , Telomerase/genética , Adulto , Idoso , Intervalo Livre de Doença , GTP Fosfo-Hidrolases/genética , Humanos , Estimativa de Kaplan-Meier , Melanoma/patologia , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Regiões Promotoras Genéticas , Modelos de Riscos Proporcionais , Proteínas Proto-Oncogênicas B-raf/genética
6.
Mediators Inflamm ; 2016: 1693918, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27478305

RESUMO

The present double-blind, randomized, placebo-controlled clinical trial intended to test whether ingestion of a natural combination medicine (Tr14 tablets) affects serum muscle damage and inflammatory immune response after downhill running. 96 male subjects received Tr14 tablets, which consist of 14 diluted biological and mineral components, or a placebo for 72 h after the exercise test, respectively. Changes in postexercise levels of various serum muscle damage and immunological markers were investigated. The area under the curve with respect to the increase (AUCi) of perceived pain score and creatine kinase (CK) were defined as primary outcome measures. While for CK the p value of the difference between the two groups is borderline, the pain score and muscle strength were not statistically significant. However, a trend towards lower levels of muscle damage (CK, p = 0.05; LDH, p = 0.06) in the Tr14 group was shown. Less pronounced lymphopenia (p = 0.02), a trend towards a lower expression of CD69 count (p = 0.07), and antigen-stimulated ICAM-1 (p = 0.01) were found in the verum group. The Tr14 group showed a tendentially lower increase of neutrophils (p = 0.10), BDNF (p = 0.03), stem cell factor (p = 0.09), and GM-CSF (p = 0.09) to higher levels. The results of the current study indicate that Tr14 seems to limit exercise-induced muscle damage most likely via attenuation of both innate and adaptive immune responses. This study was registered with ClinicalTrials.gov (NCT01912469).


Assuntos
Exercício Físico/fisiologia , Minerais/farmacologia , Músculo Esquelético/efeitos dos fármacos , Extratos Vegetais/farmacologia , Adolescente , Adulto , Apoptose/efeitos dos fármacos , Biomarcadores , Creatina Quinase/metabolismo , Método Duplo-Cego , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Voluntários Saudáveis , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Músculo Esquelético/fisiologia , Fator de Células-Tronco/metabolismo , Adulto Jovem
7.
Genes Chromosomes Cancer ; 54(4): 260-6, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25622915

RESUMO

Nonspecific chromosomal aberrations (CAs) are found in about 1% of lymphocytes drawn from healthy individuals. They include chromosome-type aberrations (CSAs), which are increased in exposure to ionizing radiation, and chromatid-type aberrations (CTAs) which in experimental systems are formed by DNA binding carcinogens and mutagens. The frequency of CAs is associated with the risk of cancer, but the causes of CAs in general population are unknown. Here, we want to test whether variants in metabolic genes associate with CAs in healthy volunteers. Cases were considered those whose total CA (CAtot) frequency was >2% and for CSA and CTA the limit was >1%. Controls had lower frequencies of CAs. Functional polymorphisms in seven genes were selected for analysis: cytochrome P450 1B1 (CYP1B1), epoxide hydrolase 1 (EPHX1), NAD(P)H:quinone oxidoreductase 1 (NQO1), each coding for phase 1 enzymes, and glutathione S-transferase P1 (GSTP1), glutathione S-transferases M1 (GSTM1) and T1 (GSTT1), coding for enzymes which conjugate reactive metabolites, that is, phase 2 enzymes. The number of volunteers genotyped for each gene varied from 550 to 1,500. Only EPHX1 was individually associated with CAtot; high activity genotypes decreased CAtot. A total of six significant (P < 0.01) pair-wise interactions were observed, most including a GST variant as one of the pair. In all genotype combinations with significant odds ratios for CAs a GST variant was involved. The present data provide evidence that variants in genes coding for metabolic enzymes, which individually have small effects, interact and are associated with CA frequencies in peripheral lymphocytes of healthy volunteers.


Assuntos
Aberrações Cromossômicas , Polimorfismo Genético , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Voluntários Saudáveis , Humanos , Masculino , Redes e Vias Metabólicas/genética , Pessoa de Meia-Idade , Adulto Jovem
8.
Carcinogenesis ; 36(11): 1299-306, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26354780

RESUMO

Human cancers are often associated with numerical and structural chromosomal instability. Structural chromosomal aberrations (CAs) in peripheral blood lymphocytes (PBL) arise as consequences of direct DNA damage or due to replication on a damaged DNA template. In both cases, DNA repair is critical and inter-individual differences in its capacity are probably due to corresponding genetic variations. We investigated functional variants in DNA repair genes (base and nucleotide excision repair, double-strand break repair) in relation to CAs, chromatid-type aberrations (CTAs) and chromosome-type aberrations (CSAs) in healthy individuals. Chromosomal damage was determined by conventional cytogenetic analysis. The genotyping was performed by both restriction fragment length polymorphism and TaqMan allelic discrimination assays. Multivariate logistic regression was applied for testing individual factors on CAs, CTAs and CSAs. Pair-wise genotype interactions of 11 genes were constructed for all possible pairs of single-nucleotide polymorphisms. Analysed individually, we observed significantly lower CTA frequencies in association with XPD Lys751Gln homozygous variant genotype [odds ratio (OR) 0.64, 95% confidence interval (CI) 0.48-0.85, P = 0.004; n = 1777]. A significant association of heterozygous variant genotype in RAD54L with increased CSA frequency (OR 1.96, 95% CI 1.01-4.02, P = 0.03) was determined in 282 subjects with available genotype. By addressing gene-gene interactions, we discovered 14 interactions significantly modulating CAs, 9 CTAs and 12 CSAs frequencies. Highly significant interactions included always pairs from two different pathways. Although individual variants in genes encoding DNA repair proteins modulate CAs only modestly, several gene-gene interactions in DNA repair genes evinced either enhanced or decreased CA frequencies suggesting that CAs accumulation requires complex interplay between different DNA repair pathways.


Assuntos
Aberrações Cromossômicas , Reparo do DNA/genética , Neoplasias/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , DNA Glicosilases/genética , Proteínas de Ligação a DNA/genética , Feminino , Frequência do Gene , Estudos de Associação Genética , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Proteína 1 Complementadora Cruzada de Reparo de Raio-X , Adulto Jovem
9.
Int J Cancer ; 134(8): 1899-906, 2014 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-24590453

RESUMO

The population attributable fraction (PAF) defines the proportion of a disease that would be prevented if the exposure to a particular risk factor was avoided. Familial risk is a known risk factor for many cancers, but an unbiased estimation of the PAF for familial risk requires a large study population to include rare cancers. PAFs and their corresponding standardized incidence ratios (SIRs) were calculated for familial relative risk among first-degree relatives (FDRs) and second-degree relatives (SDRs) diagnosed with the same (concordant) invasive or in situ cancers. Calculations were based on the Swedish Family-Cancer Database considering 8,148,737 individuals. To assess environmental effects, PAFs were also calculated for concordant cancers among spouses. Almost all cancers showed a significant familial risk. The highest PAFs were found for the common cancers of the prostate (13.94%), breast (7.46%) and colorectum (6.78%) among the FDRs. In the FDRs, the overall PAF for any concordant cancer was 4.20%, but in the SDRs, it was only 0.34%. The overall PAFs for in situ cancers were 0.86% and 0.56% for the FDRs and SDRs, respectively. The overall independent familial PAF was 5.96% for the invasive and in situ cancers in the FDRs and SDRs. The cancers between spouses yielded an overall PAF of 0.14%. For esophageal cancer, the risk among spouses was higher than the familial risk. Our study shows that the overall familial PAF of 5.96%, although underestimated for sex-specific cancers, ranks as the third most common population burden after tobacco smoking and unhealthy diet.


Assuntos
Neoplasias da Mama/epidemiologia , Neoplasias Colorretais/epidemiologia , Família , Neoplasias da Próstata/epidemiologia , Carcinoma in Situ/epidemiologia , Neoplasias Esofágicas/epidemiologia , Feminino , Humanos , Incidência , Masculino , Risco , Fatores de Risco
10.
Eur J Nutr ; 53(5): 1229-36, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24271591

RESUMO

PURPOSE: It was recently shown that niacin prevents the obesity-induced type I to type II fiber switching in skeletal muscle of obese rats and favors the development of a more oxidative metabolic phenotype and thereby increases whole body utilization of fatty acids. Whether niacin also causes type II to type I fiber switching in skeletal muscle of healthy rats has not been investigated yet. Thus, the present study aimed to investigate whether niacin supplementation influences fiber distribution and metabolic phenotype of different skeletal muscles with a distinct type I-to-type II fiber ratio in healthy rats. METHODS: Twenty-four male, 10-week-old Sprague-Dawley rats were randomly assigned into two groups of 12 rats each and fed either a control diet with 30 mg supplemented niacin/kg diet (control group) or a high-niacin diet with 780 mg supplemented niacin/kg diet (high-niacin group). RESULTS: After 27 days of treatment, the percentage number of type I fibers in rectus femoris, gastrocnemius, and tibialis anterior muscles was 5-10% greater in the niacin group than in the control group, but did not differ between groups in soleus and vastus intermedius muscles. Transcript levels of genes encoding transcription factors regulating fiber switching, fiber-specific myosin heavy chain isoforms, and proteins involved in fatty acid utilization, oxidative phosphorylation, and angiogenesis did not differ between groups. CONCLUSIONS: The results show that niacin has only negligible effects on fiber distribution and its regulation as well as the metabolic phenotype of skeletal muscle in healthy rats.


Assuntos
Suplementos Nutricionais , Fibras Musculares Esqueléticas/efeitos dos fármacos , Niacina/farmacologia , Fenótipo , Animais , Ácidos Graxos/metabolismo , Regulação da Expressão Gênica , Masculino , Fibras Musculares Esqueléticas/metabolismo , Fosforilação Oxidativa/efeitos dos fármacos , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
11.
Eur J Appl Physiol ; 114(3): 609-17, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24352573

RESUMO

PURPOSE: Many endurance athletes complain about gastrointestinal (GI) symptoms. It is assumed that exercise-induced shift of perfusion with consecutive hypoperfusion of the enteral vascular system leads to an increased GI permeability and tissue damage. Therefore, the aim of the study was to investigate permeability, apoptosis, electrogenic ion transport (Isc), and tissue conductance (Gt) of the small intestine in a murine exercise model. METHODS: After spirometry, male Swiss CD-1 mice were subjected to an intensive treadmill exercise (80% VO2max). Sedentary mice served as controls. The small intestine was removed at several time intervals post-exercise. Apoptotic cells were determined by the TUNEL method, while fluorescein isothiocyanate dextran permeation indicated intestinal permeability. The Gt and Isc measurements were carried out in a modified Ussing chamber. RESULTS: Apoptosis of epithelial cells increased continuously until 24 h post exercise (0.8 ± 0.42 versus 39.2 ± 26.0%; p < 0.05). Compared with the control group the permeability increased 2 h after exercise (0.47 ± 0.07 versus 0.67 ± 0.14 FU/min; p < 0.05). Isc measurements of the ileum were augmented after 24 h (3.33 ± 0.56 versus 5.77 ± 1.16 µEq/h/cm(2); p < 0.05). At this time the Gt increased as well (28.8 ± 3.37 versus 32.5 ± 2.59 mS/cm(2); p < 0.05). CONCLUSION: In the murine exercise model there is evidence that after intense endurance exercise repair processes occur in small intestinal epithelial cells, which affect permeability, Gt, and Isc. The formation of lamellipodia to close the "leaky" tight junctions caused by apoptosis might be an underlying mechanism.


Assuntos
Gastroenteropatias/fisiopatologia , Condicionamento Físico Animal/efeitos adversos , Condicionamento Físico Animal/fisiologia , Animais , Apoptose/fisiologia , Intestino Delgado/fisiopatologia , Transporte de Íons/fisiologia , Masculino , Camundongos , Permeabilidade
12.
J Nutr ; 143(2): 125-31, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23256146

RESUMO

In the present study, we tested the hypothesis that niacin increases the oxidative capacity of muscle by increasing the oxidative type I muscle fiber content. Twenty-four obese Zucker rats were assigned to 2 groups of 12 rats that were fed either a control diet (O group) or a diet supplemented with 750 mg/kg diet niacin (O+N group) for 4 wk. In addition, one group of lean rats (L group) was included in the experiment and fed the control diet for 4 wk. Plasma and liver concentrations of TG were markedly greater in obese groups than in the L group but markedly lower in the O+N group than in the O group (P < 0.05). Rats of the O+N group had a higher percentage of oxidative type I fibers and higher mRNA levels of genes encoding regulators of muscle fiber composition (Ppard, Ppargc1a, Ppargc1b), angiogenic factors (Vegfa, Vegfb), and genes involved in fatty acid utilization (Cpt1b, Slc25a20, Slc22a4, Slc22a5, Slc27a1) and oxidative phosphorylation (Cox4i1, Cox6a2) and a higher activity of the mitochondrial oxidative enzyme succinate dehydrogenase in muscle than rats of the O and L groups (P < 0.05). These niacin-induced changes in muscle metabolic phenotype are indicative of an increased capacity of muscle for oxidative utilization of fatty acids and are likely mediated by the upregulation of Ppard, Ppargc1a, and Ppargc1b, which are key regulators of muscle fiber composition, mitochondrial biogenesis, angiogenesis, and genes involved in fatty acid catabolism and oxidative phosphorylation. The increased utilization of fatty acids by muscle might contribute to the strong TG-lowering effect of niacin treatment.


Assuntos
Suplementos Nutricionais , Glicólise , Hipolipemiantes/uso terapêutico , Fibras Musculares de Contração Lenta/metabolismo , Niacina/uso terapêutico , Obesidade/dietoterapia , Fosforilação Oxidativa , Animais , Regulação da Expressão Gênica , Mobilização Lipídica , Fígado/metabolismo , Masculino , Renovação Mitocondrial , Fibras Musculares de Contração Lenta/enzimologia , Fibras Musculares de Contração Lenta/patologia , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Obesidade/metabolismo , Obesidade/patologia , Oxirredução , RNA Mensageiro/metabolismo , Distribuição Aleatória , Ratos , Ratos Zucker , Triglicerídeos/sangue , Triglicerídeos/metabolismo
13.
BMC Vet Res ; 9: 177, 2013 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-24010567

RESUMO

BACKGROUND: A recent study showed that niacin supplementation counteracts the obesity-induced muscle fiber switching from oxidative type I to glycolytic type II and increases the number of type I fibers in skeletal muscle of obese Zucker rats. These effects were likely mediated by the induction of key regulators of fiber transition, PGC-1α and PGC-1ß, leading to muscle fiber switching and up-regulation of genes involved in mitochondrial fatty acid import and oxidation, citrate cycle, oxidative phosphorylation, mitochondrial biogenesis. The aim of the present study was to investigate whether niacin supplementation causes type II to type I muscle and changes the metabolic phenotype of skeletal muscles in growing pigs. RESULTS: 25 male, 11 wk old crossbred pigs (Danzucht x Pietrain) with an average body weight of 32.8 ± 1.3 (mean ± SD) kg were randomly allocated to two groups of 12 (control group) and 13 pigs (niacin group) which were fed either a control diet or a diet supplemented with 750 mg niacin/kg diet. After 3 wk, the percentage number of type I fibers in three different muscles (M. longissismus dorsi, M. quadriceps femoris, M. gastrocnemius) was greater in the niacin group and the percentage number of type II fibers was lower in the niacin group than in the control group (P < 0.05). The mRNA levels of PGC-1ß and genes involved in mitochondrial fatty acid catabolism (CACT, FATP1, OCTN2), citrate cycle (SDHA), oxidative phosphorylation (COX4/1, COX6A1), and thermogenesis (UCP3) in M. longissimus dorsi were greater in the niacin group than in the control group (P < 0.05). CONCLUSIONS: The study demonstrates that niacin supplementation induces type II to type I muscle fiber switching, and thereby an oxidative metabolic phenotype of skeletal muscle in pigs. Given that oxidative muscle types tend to develop dark, firm and dry pork in response to intense physical activity and/or high psychological stress levels preslaughter, a niacin-induced change in the muscle´s fiber type distribution may influence meat quality of pigs.


Assuntos
Fibras Musculares Esqueléticas/efeitos dos fármacos , Niacina/farmacologia , Suínos/crescimento & desenvolvimento , Suínos/fisiologia , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Ácido Cítrico , Dieta/veterinária , Suplementos Nutricionais , Ácidos Graxos , Masculino , Fibras Musculares Esqueléticas/fisiologia , Niacina/administração & dosagem , Fosforilação Oxidativa , Termogênese , Complexo Vitamínico B/administração & dosagem , Complexo Vitamínico B/farmacologia
14.
Int J Occup Saf Ergon ; 28(4): 2370-2376, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34608851

RESUMO

Objectives. This crossover pilot study aimed to compare the physical load response of an ergonomically improved welding torch versus a conventional torch. Methods. Ten inexperienced volunteers performed an experimental augmented virtual welding trial at chest height (ASME code 1G) and overhead (ASME code 4G) with both welding torches in random order. Skeletal muscle load and fatigue were assessed by surface electromyography and changes in isometric peak force. The sensation of pain, perceived exertion and welding execution quality were defined as further outcome parameters. Results. The muscle load response in three out of eight muscles was lower in favour of the ergonomic welding torch, which went along with a lower sensation of pain and a higher working accuracy. Conclusions. An ergonomically improved welding torch reduces the acute physical load response and sensation of pain, which ultimately allows performing better, and might contribute to prevention of musculoskeletal diseases in the long term.


Assuntos
Soldagem , Humanos , Eletromiografia , Ergonomia , Dor , Projetos Piloto , Saúde Ocupacional , Estudos Cross-Over
15.
Metabolites ; 12(7)2022 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-35888781

RESUMO

Endurance training induces several adaptations in substrate metabolism, especially in relation to glycogen conservation. The study aimed to investigate differences in the metabolism of lipids, lipid-like substances, and amino acids between highly trained and untrained subjects using targeted metabolomics. Depending on their maximum relative oxygen uptake (VO2max), subjects were categorized as either endurance-trained (ET) or untrained (UT). Resting blood was taken and plasma isolated. It was screened for changes of 345 metabolites, including amino acids and biogenic amines, acylcarnitines, glycerophosphocholines (GPCs), sphingolipids, hexoses, bile acids, and polyunsaturated fatty acids (PUFAs) by using liquid chromatography coupled to tandem mass spectrometry. Acylcarnitine (C14:1, down in ET) and five GPCs (lysoPC a C18:2, up in ET; PC aa C42:0, up in ET; PC ae C38:2, up in ET; PC aa C38:5, down in ET; lysoPC a C26:0, down in ET) were differently regulated in ET compared to UT. TCDCA was down-regulated in athletes, while for three ratios of bile acids CA/CDCA, CA/(GCA+TCA), and DCA/(GDCA+TDCA) an up-regulation was found. TXB2 and 5,6-EET were down-regulated in the ET group and 18S-HEPE, a PUFA, showed higher levels in 18S-HEPE in endurance-trained subjects. For PC ae C38:2, TCDCA, and the ratio of cholic acid to chenodeoxycholic acid, an association with VO2max was found. Numerous phospholipids, acylcarnitines, glycerophosphocholines, bile acids, and PUFAs are present in varying concentrations at rest in ET. These results might represent an adaptation of lipid metabolism and account for the lowered cardiovascular risk profile of endurance athletes.

16.
Front Physiol ; 12: 728625, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34899372

RESUMO

Ca2+ is an important intracellular second messenger known to regulate several cellular functions. This research aimed to investigate the mechanisms of exercise-induced immunosuppression by measuring intracellular calcium levels, Ca2+-regulating gene expression, and agonist-evoked proliferation of murine splenic T lymphocytes. Mice were randomly assigned to the control, sedentary group (C), and three experimental groups, which performed a single bout of intensive and exhaustive treadmill exercise. Murine splenic lymphocytes were separated by density-gradient centrifugation immediately (E0), 3h (E3), and 24h after exercise (E24). Fura-2/AM was used to monitor cytoplasmic free Ca2+ concentration in living cells. The combined method of carboxyfluorescein diacetate succinimidyl ester (CFSE) labeling and flow cytometry was used for the detection of T cell proliferation. The transcriptional level of Ca2+-regulating genes was quantified by using qPCR. Both basal intracellular Ca2+ levels and agonist (ConA, OKT3, or thapsigargin)-induced Ca2+ transients were significantly elevated at E3 group (p<0.05 vs. control). However, mitogen-induced cell proliferation was significantly decreased at E3 group (p<0.05 vs. control). In parallel, the transcriptional level of plasma membrane Ca2+-ATPases (PMCA), sarco/endoplasmic reticulum Ca2+-ATPases (SERCA), TRPC1, and P2X7 was significantly downregulated, and the transcriptional level of IP3R2 and RyR2 was significantly upregulated in E3 (p<0.01 vs. control). In summary, this study demonstrated that acute exercise affected intracellular calcium homeostasis, most likely by enhancing transmembrane Ca2+ influx into cells and by reducing expression of Ca2+-ATPases such as PMCA and SERCA. However, altered Ca2+ signals were not transduced into an enhanced T cell proliferation suggesting other pathways to be responsible for the transient exercise-associated immunosuppression.

17.
J Occup Health ; 62(1): e12122, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32515891

RESUMO

OBJECTIVES: Welders demonstrate a significant prevalence of work-related musculoskeletal disorders as indicated by high rates of illness-related absenteeism. The aim of the study was to investigate the effects of a 24-week exercise program on workload, physical performance, and overall health in welders. METHODS: Seventy-seven professional welders were assigned to either a control group (CG), an endurance training group (ETG), or a strength training group (STG). Both groups conducted a 24-week, standardized and progressive endurance or resistance exercise training program. Before (TP1) and after training (TP2) all participants performed an experimental welding task (EWT) in order to test the hypothesis that training would reduce the relative load (%MVC) of eight skeletal muscles measured by surface electromyography. Secondary outcome measures included further EWT-induced stress parameters and a series of health-related outcome measures. RESULTS: Results revealed a lower muscle load in participants of the ETG and STG for trapezius muscle at TP2 compared to T1 (P < .05 vs CG). Rate of perceived exertion and visual analogue scale were decreased, while increase of maximum EWT duration was found in participants of the ETG and STG after training (P < .05 vs CG). At T2, body fat (%) decreased and physical performance (bicycle exercise test, isometric strength of core muscles) increased in ETG and STG (P < .05). CONCLUSION: Both regular endurance and strength training represent effective strategies for reducing workload and improving physical performance of welders. The results emphasize the importance of physical fitness for welders and might motivate health professionals in steel-industry to offer access to exercise training programs.


Assuntos
Treino Aeróbico/métodos , Desempenho Físico Funcional , Treinamento Resistido/métodos , Soldagem , Carga de Trabalho , Adulto , Eletromiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/fisiologia
18.
Sci Rep ; 10(1): 888, 2020 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-31964936

RESUMO

To date, the effects of endurance exercise training on lymphocyte physiology at the kinome level are largely unknown. Therefore, the present study used a highly sensitive peptide-based kinase activity profiling approach to investigate if the basal activity of tyrosine (Tyr) and serine/threonine (Ser/Thr) kinases of human lymphocytes is affected by the aerobic endurance training status. Results revealed that the activity of various tyrosine kinases of the FGFR family and ZAP70 was increased, whereas the activity of multiple Ser/Thr kinases such as IKKα, CaMK4, PKAα, PKCα+δ (among others) was decreased in lymphocytes of endurance trained athletes (ET). Moreover, functional associations between several differentially regulated kinases in ET-derived lymphocytes were demonstrated by phylogenetic mapping and network analysis. Especially, Ser/Thr kinases of the AGC-kinase (protein kinase A, G, and C) family represent exercise-sensitive key components within the lymphocytes kinase network that may mediate the long-term effects of endurance training. Furthermore, KEGG (Kyoto Encyclopedia of Genes and Genomes) and Reactome pathway analysis indicate that Ras as well as intracellular signaling by second messengers were found to be enriched in the ET individuals. Overall, our data suggest that endurance exercise training improves the adaptive immune competence by modulating the activity of multiple protein kinases in human lymphocytes.


Assuntos
Treino Aeróbico , Linfócitos/enzimologia , Proteínas Quinases/metabolismo , Adulto , Atletas , Teste de Esforço , Humanos , Linfócitos/fisiologia , Fosforilação , Filogenia , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Tirosina Quinases/metabolismo , Corrida , Tirosina/metabolismo
19.
Cancer Med ; 9(4): 1473-1484, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31869529

RESUMO

OBJECTIVE: The TLR3/cGAS-STING-IFN signaling has recently been reported to be disturbed in colorectal cancer due to deregulated expression of the genes involved. Our study aimed to investigate the influence of potential regulatory variants in these genes on the risk of sporadic colorectal cancer (CRC) in a Czech cohort of 1424 CRC patients and 1114 healthy controls. METHODS: The variants in the TLR3, CGAS, TMEM173, IKBKE, and TBK1 genes were selected using various online bioinformatic tools, such as UCSC browser, HaploReg, Regulome DB, Gtex Portal, SIFT, PolyPhen2, and miRNA prediction tools. RESULTS: Logistic regression analysis adjusted for age and sex detected a nominal association between CRC risk and three variants, CGAS rs72960018 (OR: 1.68, 95% CI: 1.11-2.53, P-value = .01), CGAS rs9352000 (OR: 2.02, 95% CI: 1.07-3.84, P-value = .03) and TMEM173 rs13153461 (OR: 1.53, 95% CI: 1.03-2.27, P-value = .03). Their cumulative effect revealed a threefold increased CRC risk in carriers of 5-6 risk alleles compared to those with 0-2 risk alleles. Epistatic interactions between these genes and the previously genotyped IFNAR1, IFNAR2, IFNA, IFNB, IFNK, IFNW, IRF3, and IRF7 genes, were computed to test their effect on CRC risk. Overall, we obtained nine pair-wise interactions within and between the CGAS, TMEM173, IKBKE, and TBK1 genes. Two of them remained statistically significant after Bonferroni correction. Additional 52 interactions were observed when IFN variants were added to the analysis. CONCLUSIONS: Our data suggest that epistatic interactions and a high number of risk alleles may play an important role in CRC carcinogenesis, offering novel biological understanding for the CRC management.


Assuntos
Carcinogênese/genética , Neoplasias Colorretais/genética , Epistasia Genética , Regulação Neoplásica da Expressão Gênica , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Estudos de Coortes , Colo/diagnóstico por imagem , Colo/patologia , Colonoscopia , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/patologia , Biologia Computacional , Feminino , Técnicas de Genotipagem , Voluntários Saudáveis , Humanos , Quinase I-kappa B/genética , Interferons/genética , Masculino , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Nucleotidiltransferases/genética , Polimorfismo de Nucleotídeo Único , Proteínas Serina-Treonina Quinases/genética , Reto/diagnóstico por imagem , Reto/patologia , Transdução de Sinais/genética , Receptor 3 Toll-Like/genética , Adulto Jovem
20.
Appl Opt ; 48(32): 6392-9, 2009 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-19904341

RESUMO

The primary mirror of the future European Extremely Large Telescope will be equipped with 984 hexagonal segments. The alignment of the segments in piston, tip, and tilt within a few nanometers requires an optical phasing sensor. A test bench has been designed to study four different optical phasing sensor technologies. The core element of the test bench is an active segmented mirror composed of 61 flat hexagonal segments with a size of 17 mm side to side. Each of them can be controlled in piston, tip, and tilt by three piezoactuators with a precision better than 1 nm. The context of this development, the requirements, the design, and the integration of this system are explained. The first results on the final precision obtained in closed-loop control are also presented.

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