Both acute exercise and excessive training can cause oxidative stress. The resulting increase in free radicals and the inadequate response from antioxidant systems can lead to a framework of cellular damage. An association between affected tissue and the biomarkers of oxidative stress that appear in plasma has not been clearly established. The aim of this study was to evaluate the source of oxidative stress biomarkers found in the plasma of untrained rats after a single bout of swimming exercise at 2 different intensities: low intensity (SBLIE) or high intensity (SBHIE). Immediately after the exercise, aspartate transaminase (AST), alanine transaminase (ALT), γ-glutamyltransferase (GGT), and lactate dehydrogenase (LDH) were measured in plasma to characterize cell damage. Oxidative stress was assessed using protein carbonylation (PC), total antioxidant capacity (TAC), and thiobarbituric acid reactive substances (TBARS) quantified by malondialdehyde concentration. SBHIE raised levels of plasma AST (93%) and ALT (17%), and both exercise regimens produced an increase in GGT (7%) and LDH (∼55%). Plasma levels of PC and TBARS were greater in the SBHIE group; there were no changes in TAC. SBLIE caused only a modest increase in TBARS. In muscle, there were no changes in TAC, PC, or TBARS, regardless of exercise intensity, In the liver, TAC and TBARS increased significantly in both the SBLIE and SBHIE groups. This indicates that the oxidative stress biomarkers measured in the plasma immediately after a single bout of swimming exercise were generated primarily in the liver, not in muscle.
Physical exercise is known to activate the sympathetic nervous system, which influences the production of saliva from salivary glands. Our examination of saliva collected from highly trained athletes before and after a number of physical competititions showed an increase in the secretion of S-type cystatins and cystatin C as a subacute response to aerobic and anaerobic exercise. The elevation in salivary cystatins was transient and the recovery time course differed from that of amylase and other salivary proteins. An in vitro assay was developed based on a cell line from a human submandibular gland (HSG) that differentiated into acinus-like structures. Treatments with the β-adrenergic agonist isoproterenol caused a shift in the intracellular distribution of S-type cystatins and cystatin C, promoting their accumulation at the outer regions of the acinus prior to release and suggesting the activation of a directional transport involving co-migration of both molecules. In another treatment using non-differentiated HSG cells, it was evident that both expression and secretion of cystatin C increased upon addition of the β-adrenergic agonist, and these effects were essentially eliminated by the antagonist propranolol. The HSG cell line appears to have potential as a model for exploring the mechanism of cystatin secretion, particularly the S-type cystatins that originate primarily in the submandibular glands.
Introdução: A sarcopenia é uma síndrome caracterizada por perda progressiva e generalizada de massa e força muscular esquelética com risco de comprometimento funcional, aumento da probabilidade de quedas e perda de autonomia. Método: Foi realizada uma revisão integrativa da literatura científica, com utilização de artigos publicados nas bases de dados PubMed®, BVS® e Scielo® em português e inglês. Foram utilizados para busca os descritores "sarcopenia", "idoso" or “elderly” e "proteína" or “protein” sendo cruzados para busca com o operador booleano AND. Resultados: Com prevalência que varia entre 3 a 24% em idosos, é um processo resultante de mecanismos fisiopatológicos que incluem envelhecimento, comprometimento neuromuscular, exercício físico, fatores endócrinos, estresse oxidativo e alimentação. No que diz repeito a alimentação, o consumo inadequado de calorias totais e proteínas parece ser os principais fatores contribuintes. Conclusão: a ingestão adequada de calorias e proteínas (0,8/kg/dia) e a suplementação de whey protein (20 a 40g/dia), creatina (0,3g/kg/dia), vitamina D e cálcio (1.200 a 1.500 mg por dia) podem prevenir e tratar o avanço da sarcopenia em idosos.
O envelhecimento é um processo natural e irreversível, que causa a redução da autonomia e capacidade funcional. A prática regular de atividades físicas promove manutenção das capacidades funcionais do idoso. O objetivo desta pesquisa foi comparar a capacidade funcional e aptidão física, entre idosos ativos e sedentários. Foram avaliados 80 idosos com a idade média entre 60 e 80 anos, e o método de avaliação foi o Teste de Aptidão Física para Idosos (TAFI), que mensura a capacidade funcional do indivíduo através de testes de aptidão funcional e parâmetros físicos que estão relacionados às funções diárias. Através de todos os dados coletados pôde-se perceber uma diferença significativa na força muscular de membros superiores e inferiores, resistência aeróbica, flexibilidade de membros superiores, agilidade e equilíbrio dinâmico dos idosos ativos quando comparados aos idosos sedentários. Concluiu-se, a partir destes dados, que o exercício físico regular melhora a capacidade física dos idosos.
Objective: Evaluate the relationship between exogenous subclinical hyperthyroidism and oxidative stress through the analysis of the redox profile of patients with subclinical hyperthyroidism exogenous (SCH) grade I (TSH = 0.1 to 0.4 IU/mL) and grade II (TSH < 0.1 IU/mL). Subjects and methods: We analyzed 46 patients with SCH due to the use of TSH suppressive therapy with LT4 after total thyroidectomy along with 6 control euthyroid individuals (3M and 3W). Patients were divided into two groups, G1 with TSH ≥ 0.1-0.4 IU/mL (n = 25; and 7M 14W) and G2 with TSH < 0.1 IU/mL (n = 25; and 4M 21W). Venous blood samples were collected to measure the levels of markers for oxidative damage (TBARS, FOX and protein carbonylation), muscle and liver damage (CK, AST, ALT, GGT) and antioxidants (GSH, GSSG and catalase). Results: Individuals in G2 showed a GSH/GSSG ratio ~ 30% greater than those in G1 (p = 0.004) and a catalase activity that was 4 times higher (p = 0.005). For lipid peroxidation, the levels measured in G2 were higher than both control and G1 (p = 0.05). No differences were observed for both protein carbonyl markers. G1 and G2 presented with greater indications of cell injury markers than the control group. Conclusion: TSH suppression therapy with LT4 that results in subclinical hyperthyroidism can cause a redox imbalance. The greater antioxidant capacity observed in the more suppressed group was not sufficient to avoid lipid peroxidation and cellular damage.
A incidência da doença de Alzheimer (DA), forma mais comum de demência em idosos, tem aumentado à medida que a população mundial envelhece, com milhões de pessoas afetadas em todo o mundo. Até o momento não existe um tratamento eficaz para DA, e esforços significativos são direcionados no sentido de desenvolver novas estratégias, como atividade física regular, para neutralizar os mecanismos que levam a danos neuronais. Neste sentido, este estudo teve como objetivo identificar os efeitos que a atividade física proporciona para o tratamento de idosos com Alzheimer. A metodologia aqui empregada foi uma revisão literária através de livros e artigos. Com base nessas obervações, apresentamos que a atividade física regular pode auxiliar na prevenção e no tratamento da DA, sendo praticado pelo paciente e pelos cuidadores; cabendo aos profissionais de Educação Física, o aprofundamento cada vez maior em estudos destas bases, além de informar sobre os benefícios da atividade física para o auxilio do tratamento dessa doença.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
334 Leonard St
Brooklyn, NY 11211
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.