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1.
Reprod Fertil Dev ; 35(8): 469-479, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37080254

RESUMO

CONTEXT: Sulfasalazine (SAS) is a drug prescribed for pregnant and breastfeeding women with chronic inflammatory bowel diseases. SAS treatment induces transitory infertility in both adult men and male rats. Although SAS crosses the placenta and passes into maternal milk, the consequences of maternal SAS exposure on the reproductive development of male offspring needs further study. AIMS: The current study evaluated whether maternal SAS exposure interferes with the reproductive development of male rat offspring in the neonatal, infant, pubertal and adulthood periods. METHODS: Pregnant Wistar rats (n =10/group) received 300mg/kg/day of SAS dissolved in carboxymethyl cellulose (CMC), by gavage, from gestational day 0 to lactation day 21, and 3mg/kg/day of folic acid during gestation. The control group received CMC. KEY RESULTS: During puberty, maternal SAS exposure increased the total length of seminiferous tubules, and round cells were observed in the lumen of caput and cauda epididymis. Moreover, SAS induced oxidative stress-related alterations in the testes of infant and adolescent rats. CONCLUSIONS: Although maternal SAS treatment caused reproductive alterations in infant and adolescent male rats, in adulthood, there were no impairments in sperm parameters that could compromise fertility. IMPLICATIONS: This study investigated the consequences of maternal exposure to SAS on the reproductive development of male rat offspring from birth to adulthood, employing a human-relevant dose. Thus, this study provides information for better understanding of SAS treatment during critical periods of development.


Assuntos
Efeitos Tardios da Exposição Pré-Natal , Sulfassalazina , Humanos , Gravidez , Masculino , Ratos , Feminino , Animais , Adolescente , Sulfassalazina/farmacologia , Aleitamento Materno , Ratos Wistar , Sêmen , Lactação , Exposição Materna/efeitos adversos
3.
Cells ; 11(16)2022 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-36010545

RESUMO

Calsequestrin 1 (CASQ1) and Ryanodine receptor 1 (RYR1) are two of the main players in excitation-contraction (EC) coupling. CASQ1-knockout mice and mice carrying a mutation in RYR1 (Y522S) linked to human malignant hyperthermia susceptibility (MHS) both suffer lethal hypermetabolic episodes when exposed to halothane (MHS crises) and to environmental heat (heat stroke, HS). The phenotype of Y522S is more severe than that of CASQ1-null mice. As MHS and HS are hypermetabolic responses, we studied the metabolism of adult CASQ1-null and Y522S mice using wild-type (WT) mice as controls. We found that CASQ1-null and Y522S mice have increased food consumption and higher core temperature at rest. By indirect calorimetry, we then verified that CASQ1-null and Y522S mice show an increased oxygen consumption and a lower respiratory quotient (RQ). The accelerated metabolism of CASQ1-null and Y522S mice was also accompanied with a reduction in body fat. Moreover, both mouse models displayed increased oxygen consumption and a higher core temperature during heat stress. The results collected suggest that metabolic rate, oxygen consumption, and body temperature at rest, all more elevated in Y522S than in CASQ1-null mice, could possibly be used as predictors of the level of susceptibility to hyperthermic crises of mice (and possibly humans).


Assuntos
Golpe de Calor , Hipertermia Maligna , Animais , Metabolismo Basal , Proteínas de Ligação ao Cálcio/metabolismo , Calsequestrina/genética , Calsequestrina/metabolismo , Golpe de Calor/genética , Humanos , Hipertermia Maligna/genética , Hipertermia Maligna/metabolismo , Camundongos , Camundongos Knockout , Consumo de Oxigênio , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo
4.
Cell Biochem Funct ; 40(6): 578-588, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35788958

RESUMO

Several biological activities of the fungal exopolysaccharide (1 → 3)(1 → 6)-ß-d-glucan (botryosphaeran) have been described in the literature, but its effects on inflammation have not been evaluated. This study aimed to investigate the action of botryosphaeran on experimental mice models of carrageenan-induced acute pleurisy and acute paw edema, and complete Freund's adjuvant-induced persistent paw edema. All botryosphaeran doses tested (1.0, 2.5, 5.0, and 10.0 mg/kg birth weight [b.w.], orally administered) reduced leukocyte recruitment, nitric oxide (NO) levels, and protein extravasation in the pleural cavity. Botryosphaeran (5 mg/kg b.w.) did not diminish edema and mechanical hyperalgesia in the paw within 4 h; however, cold allodynia was alleviated within the first 2 h. In the persistent paw inflammation model, the effects of daily oral administration of botryosphaeran (5 mg/kg b.w.) were evaluated over 3 and 7 days. The fungal ß-glucan significantly reduced the levels of the cytokines, tumor necrosis factor(TNF)-α, interleukin (IL)-6), and IL-10, in the paw homogenates in both protocols, while paw edema and the levels of advanced oxidation protein products (AOPP) only diminished on Day 7. No effect in mechanical hyperalgesia was observed. Oral treatment for 3 or 7 days also decreased the plasma levels of NO, AOPP, TNF-α, and IL-10. On Day 7, the number of leukocytes in the blood was also reduced by this treatment. Importantly, botryosphaeran did not induce inflammation in mice when administered alone over 7 days. This study demonstrated the anti-inflammatory and antinociceptive potential of botryosphaeran in these experimental models, making this fungal ß-glucan a new possibility for complementary treating acute and chronic inflammation.


Assuntos
Hiperalgesia , beta-Glucanas , Administração Oral , Produtos da Oxidação Avançada de Proteínas/metabolismo , Animais , Edema/induzido quimicamente , Edema/tratamento farmacológico , Edema/patologia , Glucanos/efeitos adversos , Glucanos/farmacologia , Glucanos/uso terapêutico , Hiperalgesia/induzido quimicamente , Hiperalgesia/tratamento farmacológico , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Interleucina-10 , Leucócitos/patologia , Camundongos , Nociceptividade , beta-Glucanas/efeitos adversos , beta-Glucanas/farmacologia , beta-Glucanas/uso terapêutico
5.
Int J Mol Sci ; 23(9)2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-35563676

RESUMO

Environmental heat-stroke (HS) is a life-threatening response often triggered by hot and humid weather. Several lines of evidence indicate that HS is caused by excessive heat production in skeletal muscle, which in turn is the result of abnormal Ca2+ leak from the sarcoplasmic reticulum (SR) and excessive production of oxidative species of oxygen and nitrogen. As a high fat diet is known to increase oxidative stress, the objective of the present study was to investigate the effects of 3 months of high-fat diet (HFD) on the HS susceptibility of wild type (WT) mice. HS susceptibility was tested in an environmental chamber where 4 months old WT mice were exposed to heat stress (41 °C for 1 h). In comparison with mice fed with a regular diet, mice fed with HFD showed: (a) increased body weight and accumulation of adipose tissue; (b) elevated oxidative stress in skeletal muscles; (c) increased heat generation and oxygen consumption during exposure to heat stress; and finally, (d) enhanced sensitivity to both temperature and caffeine of isolated muscles during in-vitro contracture test. These data (a) suggest that HFD predisposes WT mice to heat stress and (b) could have implications for guidelines regarding food intake during periods of intense environmental heat.


Assuntos
Dieta Hiperlipídica , Golpe de Calor , Tecido Adiposo , Animais , Dieta Hiperlipídica/efeitos adversos , Golpe de Calor/etiologia , Resposta ao Choque Térmico/fisiologia , Camundongos , Músculo Esquelético/fisiologia
6.
Med Sci Sports Exerc ; 53(8): 1572-1582, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-33731662

RESUMO

PURPOSE: This study aimed to determine the role of mammalian target of rapamycin (mTORC1) activation and catabolic markers in resistance training's (RT) antiatrophy effect during cachexia-induced muscle loss. METHODS: Myofiber atrophy was induced by injecting Walker 256 tumor cells into rats exposed or not exposed to the RT protocol of ladder climbing. The role of RT-induced anabolic stimulation was investigated in tumor-bearing rats with the mTORC1 inhibitor rapamycin, and cross-sectional areas of skeletal muscle were evaluated to identify atrophy or hypertrophy. Components of the mTORC1 and ubiquitin-proteasome pathways were assessed by real-time polymerase chain reaction or immunoblotting. RESULTS: Although RT prevented myofiber atrophy and impaired the strength of tumor-bearing rats, in healthy rats, it promoted activated mTORC1, as demonstrated by p70S6K's increased phosphorylation and myofiber's enlarged cross-sectional area. However, RT promoted no changes in the ratio of p70S6K to phospho-p70S6K protein expression while prevented myofiber atrophy in tumor-bearing rats. Beyond that, treatment with rapamycin did not preclude RT's preventive effect on myofiber atrophy in tumor-bearing rats. Thus, RT's ability to prevent cancer-induced myofiber atrophy seems to be independent of mTORC1's and p70S6K's activation. Indeed, RT's preventive effect on cancer-induced myofiber atrophy was associated with its capacity to attenuate elevated tumor necrosis factor α and interleukin 6 as well as to prevent oxidative damage in muscles and an elevated abundance of atrogin-1. CONCLUSIONS: By inducing attenuated myofiber atrophy independent of mTORC1's signaling activation, RT prevents muscle atrophy during cancer by reducing inflammation, oxidative damage, and atrogin-1 expression.


Assuntos
Músculo Esquelético/fisiopatologia , Atrofia Muscular/prevenção & controle , Neoplasias/complicações , Treinamento Resistido , Serina-Treonina Quinases TOR/metabolismo , Animais , Inflamação , Masculino , Neoplasias/fisiopatologia , Neoplasias Experimentais , Estresse Oxidativo , Fosforilação , Ratos , Ratos Wistar , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo
7.
Nutrition ; 79-80: 110958, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32882636

RESUMO

OBJECTIVES: This study aimed to analyze the effect of creatine (Cr) supplementation on tumor microenvironment, evaluating the parameters of tumor aggressiveness. METHODS: Sixteen male Wistar rats were randomly assigned to 2 groups (n = 8/group): Tumor-bearing (T) and tumor-bearing supplemented with Cr (TCr). Cr supplementation was provided in drinking water for a total of 21 d. After 11 d of Cr supplementation (TCr group) or water (T group), Walker-256 tumor cells were inoculated subcutaneously in the right flank of all rats, which kept receiving Cr supplementation (TCr group) or water (T group) for 10 more days. The total period of the experiment was 21 d. RESULTS: Tumor weight corresponded with approximately 3.5% ± 0.9% of animal body weight in the T group. Cr supplementation did not accelerate tumor growth or increase tumor size. The histopathological analysis demonstrated the presence of nuclear pleomorphisms and atypical nuclei, with the presence of low-differentiated tumor cells, in both groups. Cr supplementation did not alter apoptosis and cell proliferation markers, nor tumor capsule thickness and viable tumor area. CONCLUSIONS: Cr supplementation in Walker-256 tumor-bearing rats did not induce significant changes in tumor development, and did not interfere with the parameters of tumor aggressiveness, such as the level of cell differentiation and proliferation.


Assuntos
Carcinoma 256 de Walker , Neoplasias , Animais , Apoptose , Carcinoma 256 de Walker/tratamento farmacológico , Creatina , Suplementos Nutricionais , Masculino , Ratos , Ratos Wistar , Microambiente Tumoral
8.
Appl Physiol Nutr Metab ; 45(9): 978-986, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32813570

RESUMO

Cigarette smoke (CS) exposure reduces skeletal muscle function; however, the mechanisms involved have been poorly investigated. The current study evaluated the temporal effects of aerobic exercise training on oxidant and antioxidant systems as well as inflammatory markers in skeletal muscle of mice exposed to CS. Mice were randomly allocated to control, exercise, smoke, and smoke+exercise groups and 3 time points (4, 8, and 12 weeks; n = 12 per group). Exercise training and CS exposure were performed for 30 min/day, twice a day, 5 days/week for 4, 8, and 12 weeks. Aerobic exercise improved functional capacity and attenuated the increase in the cachexia index induced by CS exposure after 12 weeks. Concomitantly, exercise training downregulated tumor necrosis factor α concentration, glutathione oxidation, and messenger RNA (mRNA) expression of Keap1 (P < 0.01) and upregulated interleukin 10 concentration, total antioxidant capacity, and mRNA expression of Nrf2, Gsr, and Txn1 (P < 0.01) in muscle. Exercise increased mRNA expression of Hmox1 compared with the control after 12 weeks (P < 0.05). There were no significant differences between smoke groups for superoxide dismutase activity and Hmox1 mRNA expression. Exercise training improved the ability of skeletal muscle to adequately upregulate key antioxidant and anti-inflammatory defenses to detoxify electrophilic compounds induced by CS exposure, and these effects were more pronounced after 12 weeks. Novelty Exercise attenuates oxidative stress in skeletal muscle from animals exposed to CS via Nrf2 and glutathione pathways. Exercise is a helpful tool to control the inflammatory balance in skeletal muscle from animals exposed to CS. These beneficial effects were evident after 12 weeks.


Assuntos
Citocinas/metabolismo , Músculo Esquelético/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Condicionamento Físico Animal , Fumaça/efeitos adversos , Animais , Antioxidantes/metabolismo , Caquexia , Fumar Cigarros/efeitos adversos , Glutationa/metabolismo , Interleucina-10/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Músculo Esquelético/efeitos dos fármacos , Estresse Oxidativo , Superóxido Dismutase/metabolismo
9.
Eur J Nutr ; 59(2): 661-669, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30806774

RESUMO

PURPOSE: The aim of this study was to investigate the effects of creatine supplementation on muscle wasting in Walker-256 tumor-bearing rats. METHODS: Wistar rats were randomly assigned into three groups (n = 10/group): control (C), tumor bearing (T), and tumor bearing supplemented with creatine (TCr). Creatine was provided in drinking water for a total of 21 days. After 11 days of supplementation, tumor cells were implanted subcutaneously into T and TCr groups. The animals' weight, food and water intake were evaluated along the experimental protocol. After 10 days of tumor implantation (21 total), animals were euthanized for inflammatory state and skeletal muscle cross-sectional area measurements. Skeletal muscle components of ubiquitin-proteasome pathways were also evaluated using real-time PCR and immunoblotting. RESULTS: The results showed that creatine supplementation protected tumor-bearing rats against body weight loss and skeletal muscle atrophy. Creatine intake promoted lower levels of plasma TNF-α and IL-6 and smaller spleen morphology changes such as reduced size of white pulp and lymphoid follicle compared to tumor-bearing rats. In addition, creatine prevented increased levels of skeletal muscle Atrogin-1 and MuRF-1, key regulators of muscle atrophy. CONCLUSION: Creatine supplementation prevents skeletal muscle atrophy by attenuating tumor-induced pro-inflammatory environment, a condition that minimizes Atrogin-1 and MuRF-1-dependent proteolysis.


Assuntos
Carcinoma 256 de Walker/metabolismo , Creatina/farmacologia , Suplementos Nutricionais , Inflamação/prevenção & controle , Atrofia Muscular/prevenção & controle , Proteólise/efeitos dos fármacos , Animais , Creatina/administração & dosagem , Modelos Animais de Doenças , Masculino , Músculo Esquelético/efeitos dos fármacos , Ratos , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos
10.
Med Sci Sports Exerc ; 51(10): 2003-2011, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30985506

RESUMO

PURPOSE: Although resistance exercise (RE) is now recognized as an adjuvant in cancer treatment because of its capacity to prevent muscle wasting, weakness, and cachexia, it is unknown whether RE can mitigate tumor development. Two solid adenocarcinoma models (Walker-256 and Ehrlich) were used to investigate the effects of RE on tumor cell proliferation, growth, and aggressiveness parameters in tumor-bearing animals' life span. METHODS: Walker-256 tumor-bearing rats and Ehrlich tumor-bearing mice were subjected to RE, which consisted of climbing a ladder apparatus with loads tied to their tails. After 4 wk, animals were euthanized, and tumors were excised and assessed for tumor microenvironment evaluation such as cell proliferation and apoptosis determination, collagen deposit, and presence of malignant tumor morphology. RESULTS: Our data demonstrate that RE mitigated tumor growth and favored tumor end points such as lower Scarff-Bloom-Richardson histological grade tumor, denoting slow cell aberrant form and division, decreased tumor cell proliferation (evaluated by nucleus marked with antigen ki-67), and lower viable tumor area in both types of tumors studied. In addition, RE stimulated tumor microvessel density in Walker-256 tumor-bearing rats, but there was no change in their life span. CONCLUSION: RE may mitigate tumor growth and tumor malignancy parameters such as lower histopathological grade, assuming less nuclear pleomorphism and mitotic cells, smaller viable tumor area, and decreased tumor cell proliferation in both adenocarcinomas. In addition, RE induced tumor vascularization.


Assuntos
Carcinoma de Ehrlich/patologia , Condicionamento Físico Animal/fisiologia , Treinamento Resistido , Animais , Apoptose , Carcinoma de Ehrlich/metabolismo , Proliferação de Células , Colágeno/metabolismo , Modelos Animais de Doenças , Antígeno Ki-67/análise , Masculino , Camundongos , Ratos Wistar , Microambiente Tumoral
11.
Arch Biochem Biophys ; 663: 173-182, 2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-30639329

RESUMO

Muscle wasting or atrophy is extensively associated with human systemic diseases including diabetes, cancer, and kidney failure. Accumulating evidence from transcriptional profiles has noted that a common set of genes, termed atrogenes, is modulated in atrophying muscles. However, the transcriptional changes that trigger the reversion or attenuation of muscle atrophy have not been characterized at the molecular level until now. Here, we applied cDNA microarrays to investigate the transcriptional response of androgen-sensitive Levator ani muscle (LA) during atrophy reversion. Most of the differentially expressed genes behaved as atrogenes and responded to castration-induced atrophy. However, seven genes (APLN, DUSP5, IGF1, PIK3IP1, KLHL38, PI15, and MKL1) did not respond to castration but instead responded exclusively to testosterone replacement. Considering that almost all proteins encoded by these genes are associated with the reversion of atrophy and may function as regulators of cell proliferation/growth, our results provide new perspectives on the existence of anti-atrogenes.


Assuntos
Androgênios/metabolismo , Perfilação da Expressão Gênica , Músculo Esquelético/metabolismo , Atrofia Muscular/metabolismo , Animais , Jejum , Terapia de Reposição Hormonal , Masculino , Camundongos , Modelos Biológicos , Músculo Esquelético/patologia , Análise de Sequência com Séries de Oligonucleotídeos , Orquiectomia , Ratos , Ratos Wistar , Testosterona/administração & dosagem
12.
J Strength Cond Res ; 33(2): 502-513, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28277426

RESUMO

de Freitas, VH, Ramos, SP, Bara-Filho, MG, Freitas, DGS, Coimbra, DR, Cecchini, R, Guarnier, FA, and Nakamura, FY. Effect of cold water immersion performed on successive days on physical performance, muscle damage, and inflammatory, hormonal, and oxidative stress markers in volleyball players. J Strength Cond Res 33(2): 502-513, 2019-The aim of this study was to investigate the effects of daily cold water immersion (CWI) on physical performance, muscle damage, and inflammatory, hormonal, and oxidative stress markers in volleyball. Six players were submitted to CWI and six players to a placebo, during 5 training days. Thigh circumference, squat jump, and agility were measured on the first, third, and sixth days. On the first and sixth days, blood and saliva were collected for analysis of oxidative stress, muscle damage, and inflammatory and hormonal levels. Muscle soreness and countermovement jump were quantified daily. The physical performance comparisons did not present differences and the only between group comparison with a large effect size (ES = -1.39) was in Δ% between day 1 and day 2 for countermovement jump. Delayed onset muscle soreness and creatine kinase increased in both groups and the ESs of between group comparisons of Δ% between moments were not more than moderate. Thigh circumference increased only in the placebo group (p = 0.04) and the ES of the between group comparisons of Δ% between moments was large (1.53). No differences were found in oxidative stress, or inflammatory markers. Cortisol decreased only in the CWI-group (p ≤ 0.05) and the ESs of the between group comparisons of Δ% between moments of the testosterone to cortisol ratio (-1.94) and insulin-like growth-1 (-1.34) were large. Despite the positive effects of daily CWI on muscle edema and hormonal status, the limited effects of CWI on performance, muscle damage, inflammation markers, and reactive oxygen species mediators signal the unimportance of the daily practice of this recovery method in volleyball players.


Assuntos
Desempenho Atlético/fisiologia , Temperatura Baixa , Músculo Esquelético/fisiologia , Voleibol/fisiologia , Água , Adulto , Biomarcadores , Creatina Quinase/sangue , Humanos , Imersão , Mediadores da Inflamação/fisiologia , Masculino , Mialgia/fisiopatologia , Estresse Oxidativo/fisiologia , Esteroides/metabolismo , Adulto Jovem
13.
Biol Reprod ; 100(1): 112-122, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30010983

RESUMO

Spermatogenesis and steroidogenesis are not fully established during puberty. Especially during this period, children and adolescents may be chronically sleep deprived due to early school hours and constant exposure to artificial light and interactive activities. We have previously shown that sleep restriction (SR) during peripuberty impairs sperm motility and has consequences on epididymal development in rats. Thus, this study aimed to evaluate the effect of SR during peripuberty on sexual hormones and its impact on testicular tissue. Rats were subjected to 18 h of SR per day for 21 days or were maintained as controls (C) in the same room. The circulating luteinizing hormone levels were decreased in SR rats without changes in the follicle stimulating hormone levels. Plasma and intratesticular testosterone and corticosterone in the SR group were increased in relation to C group. These alterations impair testicular tissue, with decreased IL-1ß, IL-6, and TNFα levels in the testis and diminished seminiferous epithelium height and Sertoli cell number. SR also increased testicular lipid peroxidation with no alteration in antioxidant profiles. There were no significant changes in sperm parameters, seminiferous tubule diameter, histopathology, spermatogenesis kinetics, neutrophil and macrophage recruitment, and IL-10 concentration. Our results show that SR unbalances sexual hormones and testicular cytokines at a critical period of sexual maturation. These changes lead to lipid peroxidation in the testes and negatively influence the testicular tissue, as evidenced by diminished seminiferous epithelium height-with apoptosis of germinative cell-and Sertoli cell number.


Assuntos
Citocinas/metabolismo , Hormônios Esteroides Gonadais/metabolismo , Maturidade Sexual/fisiologia , Privação do Sono/metabolismo , Privação do Sono/fisiopatologia , Testículo/metabolismo , Animais , Células Cultivadas , Hormônios Esteroides Gonadais/sangue , Inflamação/metabolismo , Masculino , Tamanho do Órgão , Estresse Oxidativo/fisiologia , Ratos , Ratos Wistar , Análise do Sêmen , Testículo/crescimento & desenvolvimento , Testículo/fisiopatologia
14.
Arch Biochem Biophys ; 663: 22-33, 2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-30578752

RESUMO

In fast-twitch fibers from adult mice Ca2+ release units (CRUs, i.e. intracellular junctions of excitation-contraction coupling), and mitochondria are structurally linked to each other by small strands, named tethers. We recently showed that aging causes separation of a fraction of mitochondria from CRUs and a consequent impairment of the Ca2+ signaling between the two organelles. However, whether the uncoupling of mitochondria from CRUs is the result of aging per-se or the consequence of reduced muscle activity remains still unclear. Here we studied the association between mitochondria and CRUs: in a) extensor digitorum longus (EDL) muscles from 2 years old mice, either sedentary or trained for 1 year in wheel cages; and b) denervated EDL muscles from adult mice and rats. We analyzed muscle samples using a combination of structural (confocal and electron microscopy), biochemical (assessment of oxidative stress via western blot), and functional (ex-vivo contractile properties, and mitochondrial Ca2+ uptake) experimental procedures. The results collected in structural studies indicate that: a) ageing and denervation result in partial uncoupling between mitochondria and CRUs; b) exercise either maintains (in old mice) or restores (in transiently denervated rats) the association between the two organelles. Functional studies supported the hypothesis that CRU-mitochondria coupling is important for mitochondrial Ca2+ uptake, optimal force generation, and muscle performance. Taken together our results indicate that muscle activity maintains/improves proper association between CRUs and mitochondria.


Assuntos
Envelhecimento/fisiologia , Cálcio/metabolismo , Mitocôndrias Musculares/metabolismo , Músculo Esquelético/fisiologia , Comportamento Sedentário , Envelhecimento/metabolismo , Animais , Camundongos , Camundongos Endogâmicos C57BL , Estresse Oxidativo , Ratos , Ratos Sprague-Dawley
15.
Oxid Med Cell Longev ; 2017: 6792694, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29062463

RESUMO

Central core disease (CCD) is a congenital myopathy linked to mutations in the ryanodine receptor type 1 (RYR1), the sarcoplasmic reticulum Ca2+ release channel of skeletal muscle. CCD is characterized by formation of amorphous cores within muscle fibers, lacking mitochondrial activity. In skeletal muscle of RYR1Y522S/WT knock-in mice, carrying a human mutation in RYR1 linked to malignant hyperthermia (MH) with cores, oxidative stress is elevated and fibers present severe mitochondrial damage and cores. We treated RYR1Y522S/WT mice with N-acetylcysteine (NAC), an antioxidant provided ad libitum in drinking water for either 2 or 6 months. Our results show that 2 months of NAC treatment starting at 2 months of age, when mitochondrial and fiber damage was still minimal, (i) reduce formation of unstructured and contracture cores, (ii) improve muscle function, and (iii) decrease mitochondrial damage. The beneficial effect of NAC treatment is also evident following 6 months of treatment starting at 4 months of age, when structural damage was at an advanced stage. NAC exerts its protective effect likely by lowering oxidative stress, as supported by the reduction of 3-NT and SOD2 levels. This work suggests that NAC administration is beneficial to prevent mitochondrial damage and formation of cores and improve muscle function in RYR1Y522S/WT mice.


Assuntos
Antioxidantes/metabolismo , Músculo Esquelético/fisiologia , Miopatia da Parte Central/genética , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Animais , Humanos , Camundongos , Miopatia da Parte Central/patologia
16.
J Appl Physiol (1985) ; 123(3): 674-683, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28729393

RESUMO

A previous study by our group showed that regular exercise training (ET) attenuated pulmonary injury in an experimental model of chronic exposure to cigarette smoke (CS) in mice, but the time-course effects of the mechanisms involved in this protection remain poorly understood. We evaluated the temporal effects of regular ET in an experimental model of chronic CS exposure. Male C57BL/6 mice were divided into four groups: Control (sedentary + air), Exercise (aerobic training + air), Smoke (sedentary + smoke), and Smoke + Exercise (aerobic training + smoke). Mice were exposed to CS and ET for 4, 8, or 12 wk. Exercise protected mice exposed to CS from emphysema and reductions in tissue damping and tissue elastance after 12 wk (P < 0.01). The total number of inflammatory cells in the bronchoalveolar lavage increased in the Smoke group, mainly due to the recruitment of macrophages after 4 wk, neutrophils and lymphocytes after 8 wk, and lymphocytes and macrophages after 12 wk (P < 0.01). Exercise attenuated this increase in mice exposed to CS. The protection conferred by exercise was mainly observed after exercise adaptation. Exercise increased IL-6 and IL-10 in the quadriceps and lungs (P < 0.05) after 12 wk. Total antioxidant capacity and SOD was increased and TNF-α and oxidants decreased in lungs of mice exposed to CS after 12 wk (P < 0.05). The protective effects of exercise against lung injury induced by cigarette smoke exposure suggests that anti-inflammatory mediators and antioxidant enzymes play important roles in chronic obstructive pulmonary disease development mainly after the exercise adaptation.NEW & NOTEWORTHY These experiments investigated for the first time the temporal effects of regular moderate exercise training in cigarette smoke-induced chronic obstructive pulmonary disease. We demonstrate that aerobic conditioning had a protective effect in emphysema development induced by cigarette smoke exposure. This effect was most likely secondary to an effect of exercise on oxidant-antioxidant balance and anti-inflammatory mediators.


Assuntos
Condicionamento Físico Animal/fisiologia , Doença Pulmonar Obstrutiva Crônica/prevenção & controle , Fumaça/efeitos adversos , Produtos do Tabaco/efeitos adversos , Animais , Antioxidantes/metabolismo , Líquido da Lavagem Broncoalveolar/química , Inflamação/metabolismo , Inflamação/fisiopatologia , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Pulmão/metabolismo , Pulmão/fisiopatologia , Macrófagos/metabolismo , Macrófagos/fisiologia , Macrófagos Alveolares/metabolismo , Macrófagos Alveolares/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neutrófilos/metabolismo , Neutrófilos/fisiologia , Estresse Oxidativo/fisiologia , Doença Pulmonar Obstrutiva Crônica/metabolismo , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Enfisema Pulmonar/metabolismo , Enfisema Pulmonar/fisiopatologia , Fator de Necrose Tumoral alfa/metabolismo
17.
Reprod Fertil Dev ; 29(11): 2245-2254, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28384430

RESUMO

Bisphenol A (BPA) is considered a potent endocrine disruptor, causing changes in the endocrine system due to its oestrogenic activity. Male individuals may be susceptible to endocrine, morphological and physiological alterations during testicular postnatal development. The aim of the present study was to evaluate whether exposure to BPA during the peripubertal period can damage testicular development. To this end, male Wistar rats were treated with BPA via gavage at doses of 20 or 200µgkg-1 on Postnatal Days (PND) 36-66. The control group was treated with Oil+DMSO under the same conditions. On PND 67, rats were killed. The blood was collected for hormonal analysis, the testis for sperm count, oxidative stress, histopathological and immunohistochemical analyses for ki-67 and sperm of the vas deferens for morphological analysis. Both doses of BPA resulted in abnormal sperm morphology and seminiferous tubules, with the highest dose increasing the height of the germinal epithelium and reducing the number of spermatozoa at Stages IX-XIII of spermatogenesis. In conclusion, both doses of BPA administered during the peripubertal period impaired testicular development without any effects on hormone levels (luteinizing hormone (LH), follicle stimulating hormone (FSH) and testosterone levels) or oxidative stress.


Assuntos
Compostos Benzidrílicos/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Fenóis/farmacologia , Espermatozoides/efeitos dos fármacos , Testículo/efeitos dos fármacos , Animais , Forma Celular/efeitos dos fármacos , Hormônio Foliculoestimulante/sangue , Hormônio Luteinizante/sangue , Masculino , Ratos , Ratos Wistar , Contagem de Espermatozoides , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatogênese/efeitos dos fármacos , Espermatozoides/citologia , Testículo/crescimento & desenvolvimento , Testosterona/sangue
18.
Reprod Fertil Dev ; 29(9): 1813-1820, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27780518

RESUMO

Good sleep quality has a direct effect on the activity of the neuroendocrine-reproductive control axis and oxidative stress. Thus, the aim of the present study was to evaluate whether sleep restriction (SR) during the peripubertal period impaired the postnatal development of the epididymis in Wistar rats. After 21 days SR (18h per day), epididymides were collected on Postnatal Day (PND) 62 for evaluation of oxidative stress markers, inflammatory profile, sperm count and histopathological and stereological analyses; in addition, the motility of spermatozoa from the vas deferens was examined. SR significantly increased lipid peroxidation and glutathione levels in the caput and cauda epididymidis, and increased levels of total radical-trapping antioxidant potential in the caput epididymidis only. Neutrophil migration to the caput or corpus epididymidis was decreased by SR, and the size of the luminal compartment in the 2A region and the epithelial compartment in the 5A/B region was also decreased. In these regions, there was an increase in the size of the interstitial compartment. The percentage of immotile spermatozoa was higher in the SR group. In conclusion, SR affects epididymal postnatal development, as well as sperm motility, in association with increased oxidative stress and a decrease in the size of the epithelial compartment in the cauda epididymidis.


Assuntos
Epididimo/crescimento & desenvolvimento , Estresse Oxidativo/fisiologia , Privação do Sono/fisiopatologia , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/metabolismo , Animais , Movimento Celular/fisiologia , Epididimo/metabolismo , Epididimo/fisiopatologia , Peroxidação de Lipídeos/fisiologia , Masculino , Neutrófilos/fisiologia , Ratos , Ratos Wistar , Privação do Sono/metabolismo
19.
Muscle Nerve ; 56(5): 975-981, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28029692

RESUMO

INTRODUCTION: We sought to verify whether isoflavin-beta (Iso-ß), a mixture of isoflavones with antioxidant properties, could prevent thyrotoxicosis-induced loss of muscle mass and the participation of oxidative stress (OS) in the mechanisms of this prevention. METHODS: Two experimental periods of thyrotoxicosis induction were used in Wistar rats: 3 and 5 days to assess Iso-ß effects before and after thyrotoxicosis-induced muscle wasting. After euthanasia, peritoneal fat and gastrocnemius muscle were collected, weighed, and muscle OS was assessed. RESULTS: Iso-ß prevented the loss of gastrocnemius mass in thyrotoxic rats through the prevention of muscle OS generation during thyrotoxicosis, increasing muscle total antioxidant capacity and decreasing mitochondrial cytochrome c oxidase activity, lipid peroxidation, and protein carbonyl content. CONCLUSION: Iso-ß decreased oxidative modification of proteins, which is known to exert a major role during proteolysis induction and is present in thyrotoxic myopathy, highlighting the potential action of Iso-ß in this complication of the disease. Muscle Nerve 56: 975-981, 2017.


Assuntos
Antioxidantes/uso terapêutico , Isoflavonas/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , Tireotoxicose/patologia , Tireotoxicose/prevenção & controle , Animais , Antioxidantes/farmacologia , Quimotripsina/metabolismo , Cicloexanóis/sangue , Cicloexanóis/toxicidade , Modelos Animais de Doenças , Esquema de Medicação , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Glicerol/sangue , Isoflavonas/farmacologia , Masculino , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/patologia , Atrofia Muscular , Carbonilação Proteica/efeitos dos fármacos , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Tireotoxicose/sangue , Tireotoxicose/induzido quimicamente , terc-Butil Hidroperóxido/metabolismo
20.
PLoS One ; 11(9): e0162998, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27635657

RESUMO

Gastrointestinal dysmotility frequently occurs in cancer cachexia and may result from damage to enteric innervation caused by oxidative stress, especially due to glutathione depletion. We assessed the effect of dietary supplementation with 20 g/kg l-glutamine (a glutathione precursor) on the intrinsic innervation of the enteric nervous system in healthy and Walker 256 tumor-bearing Wistar rats during the development of experimental cachexia (14 days), in comparison with non-supplemented rats, by using immunohistochemical methods and Western blotting. The total neural population and cholinergic subpopulation densities in the myenteric plexus, as well as the total population and VIPergic subpopulation in the submucosal plexus of the jejunum and ileum, were reduced in cachectic rats, resulting in adaptive morphometric alterations and an increase in vasoactive intestinal peptide (VIP) and calcitonin gene-related peptide (CGRP) expression, suggesting a neuroplastic response. l-glutamine supplementation prevented decrease in myenteric neuronal density in the ileum, morphometric alterations in the neurons and nerve fibers (in both the plexuses of the jejunum and ileum), and the overexpression of VIP and CGRP. Cancer cachexia severely affected the intrinsic innervation of the jejunum and ileum to various degrees and this injury seems to be associated with adaptive neural plasticity. l-glutamine supplementation presented partial protective effects on the enteric innervation against cancer cachexia, possibly by attenuating oxidative stress.


Assuntos
Caquexia/complicações , Suplementos Nutricionais , Glutamina/administração & dosagem , Mucosa Intestinal/metabolismo , Neoplasias/complicações , Neurônios/patologia , Caquexia/patologia , Linhagem Celular Tumoral , Humanos , Neoplasias/patologia
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