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2.
Rheumatol Adv Pract ; 8(1): rkae013, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38384323

RESUMO

Objectives: To compare the prevalence of anxiety and depression in patients with GCA with that in the general population, using the Hospital Anxiety and Depression Scale (HADS), and to identify independent predictors of these psychiatric manifestations in patients with GCA. Methods: We conducted a cross-sectional study including all patients diagnosed with GCA followed during 1 year in a vasculitis outpatient clinic. The HADS and 36-item Short Form (SF-36) questionnaires were prospectively collected. Patients' HADS results were compared with an age- and gender-matched control group. HADS anxiety (HADS-A) and HADS depression (HADS-D) scores between 8 and 10 defined possible anxiety and depression and ≥11 defined probable anxiety and depression, respectively. Results: We included 72 patients and 288 controls. Compared with controls, patients with GCA had a statistically significant higher prevalence of HADS-A ≥8 (48.6% vs 26.4%), HADS-A ≥11 (30.6% vs 12.2%) and HADS-D ≥11 (33.3% vs 18.1%). GCA was an independent predictor of HADS-A ≥8 [odds ratio (OR) 3.3 (95% CI 1.9, 5.9)], HADS-A ≥11 [OR 3.8 (95% CI 2.0, 7.4)] and HADS-D ≥11 [OR 2.6 (95% CI 1.4, 4.7)]. Among patients with GCA, a negative correlation was observed between HADS-A/D and SF-36 mental health scores (r = -0.780 and r = -0.742, respectively). Glucocorticoid therapy was a predictor of HADS-A ≥8 [OR 10.4 (95% CI 1.2, 94.2)] and older age of HADS-D ≥8 [OR 1.2 (95% CI 1.1, 1.3)] and HADS-D ≥11 [OR 1.1 (95% CI 1.0, 1.2)]. Conclusions: Compared with the general population, patients with GCA have a higher prevalence of anxiety and depression and GCA is an independent predictor of these symptoms. Glucocorticoid treatment and older age are predictors of anxiety and depression, respectively, in patients with GCA.

3.
Biochim Biophys Acta Mol Cell Biol Lipids ; 1869(3): 159465, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38350538

RESUMO

This study explores the intricate relationship between the yeast vacuolar H+-ATPase (V-ATPase) and neutral lipid metabolism. We show that LD generation observed upon loss of V-ATPase activity is crucial for survival in lipotoxic conditions. Moreover, the study uncovers a link between V-ATPase function, inositol metabolism and the activation of the oxidative pentose phosphate pathway, highlighting its pivotal role in counteracting oxidative stress. This work provides foundational insights into metabolic adaptations triggered by V-ATPase dysfunction, shedding light on cellular adaptability under lipotoxic and oxidative stress conditions.


Assuntos
Proteínas de Saccharomyces cerevisiae , ATPases Vacuolares Próton-Translocadoras , Proteínas de Saccharomyces cerevisiae/metabolismo , ATPases Vacuolares Próton-Translocadoras/metabolismo , Gotículas Lipídicas/metabolismo , Saccharomyces cerevisiae/metabolismo , Homeostase , Lipídeos
4.
Front Sports Act Living ; 6: 1334739, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38318484

RESUMO

Introduction: In the current experiment, we aimed to evaluate whether eliciting pre-exercise non-thermal cooling sensations would alter perceptual measures, and physical and physiological responses in football referees. Methods: Nine highly trained male football referees undertook two 45-minute intermittent exercise protocols in hot and humid conditions (34.2 ± 0.6°C, 62.5 ± 1.0% relative humidity). In a randomized counterbalanced crossover design, 1 of 2 beverages were given before the warm-up: a 0.01% menthol solution or a placebo noncaloric solution. Physical performance was quantified as total distance covered in each of the three 15-minute exercise blocks. Core temperature, heart rate, thermal sensation and thermal comfort were measured at rest and after each exercise block. Results: No changes were observed between trials and over time for distance covered. No main effect of mouth rinse was observed for core temperature and heart rate, but both increased over time in all conditions (P < 0.001). Thermal sensation and thermal comfort were significantly improved with menthol after mouth-rinsing (P < 0.05), but with no differences at any other time-point. Discussion: These results indicate that non-thermal cooling oral stimuli provide immediate behavioral changes but may not influence physiological or physical responses in football referees, during intermittent exercise in hot and humid environments. Clinical Trial Registration: www.clinicaltrials.gov, identifier NCT05632692.

5.
Nutr Health ; 30(1): 5-13, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37499218

RESUMO

Background: Cardiovascular disease is the leading cause of mortality associated with diabetes, which is characterized by chronic hyperglycemia. Low-carbohydrate diet has gained popularity as an intervention in patients with type 2 diabetes mellitus, acting to improve glycemic profile and serum lipids. In its turn, exercise in hypoxia induces specific adaptations, mostly modulated via hypoxia-induced transcription factor signaling cascade, which increases with exposure to altitude, and promotes angiogenesis, glycogen supply, glucose tolerance, and raises GLUT-4 expression. Aim: Given that hyperglycemia decreases HIF-1α and it is better controlled when following a low-carbohydrate diet, this study aims to examine the hypothesis that a combination of both low-carbohydrate diet and chronic exercise in hypoxia in type 2 diabetes mellitus is associated with improved glycemic control and cardiovascular parameters, whose protocol is described. Methods: Patients with type 2 diabetes mellitus (n = 48) will be recruited and randomized into one of the three groups: (a) Control group: Control diet (low-fat and moderate-carbohydrate diet) + exercise in normoxia; (2) exercise in hypoxia group: Control diet + exercise in hypoxia; (3) intervention group: Low-carbohydrate diet (low-carbohydrate and high-fat diet) + exercise in hypoxia. Before and after 8 weeks of interventions, cardiopulmonary tests (Bruce protocol), body composition and blood pressure will be evaluated. Blood samples will be collected to measure hypoxia-induced transcription factor, C-reactive protein, glycemic and lipid profiles. Summary: This will be the first trial to examine the isolated and combined effect of chronic exercise in hypoxia and low-carbohydrate diet in type 2 diabetes mellitus. This trial will help to fill a significant research gap, guide future research and contribute to the combined nutrition and exercise approach to type 2 diabetes mellitus.


Assuntos
Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Hiperglicemia , Humanos , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/prevenção & controle , Glicemia/metabolismo , Controle Glicêmico , Fatores de Risco , Dieta com Restrição de Carboidratos , Composição Corporal , Fatores de Risco de Doenças Cardíacas , Hipóxia , Fatores de Transcrição/metabolismo , Ensaios Clínicos Controlados Aleatórios como Assunto
6.
Rheumatology (Oxford) ; 63(4): 999-1006, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-37354498

RESUMO

OBJECTIVE: Data on ANCA-associated vasculitis (AAV) induced by anti-thyroid drugs (ATD) are scarce. We aimed to describe the characteristics and outcome of these patients in comparison to primary AAV. METHODS: We performed a retrospective multicentre study including patients with ATD-induced AAV. We focused on ATD-induced microscopic polyangiitis (MPA) and compared them with primary MPA by matching each case with four controls by gender and year of diagnosis. RESULTS: Forty-five patients with ATD-induced AAV of whom 24 MPA were included. ANCA were positive in 44 patients (98%), including myeloperoxidase (MPO)-ANCA in 21 (47%), proteinase 3 (PR3)-ANCA in six (13%), and double positive MPO- and PR3-ANCA in 15 (33%). Main clinical manifestations were skin involvement (64%), arthralgia (51%) and glomerulonephritis (20%). ATD was discontinued in 98% of cases, allowing vasculitis remission in seven (16%). All the remaining patients achieved remission after glucocorticoids, in combination with rituximab in 11 (30%) or cyclophosphamide in four (11%). ATD were reintroduced in seven cases (16%) without any subsequent relapse. Compared with 96 matched primary MPA, ATD-induced MPA were younger at diagnosis (48 vs 65 years, P < 0.001), had more frequent cutaneous involvement (54 vs 25%, P = 0.007), but less frequent kidney (38 vs 73%, P = 0.02), and a lower risk of relapse (adjusted HR 0.07; 95% CI 0.01, 0.65, P = 0.019). CONCLUSION: ATD-induced AAV were mainly MPA with MPO-ANCA, but double MPO- and PR3-ANCA positivity was frequent. The most common manifestations were skin and musculoskeletal manifestations. ATD-induced MPA were less severe and showed a lower risk of relapse than primary MPA.


Assuntos
Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos , Granulomatose com Poliangiite , Poliangiite Microscópica , Humanos , Granulomatose com Poliangiite/diagnóstico , Estudos Retrospectivos , Anticorpos Anticitoplasma de Neutrófilos , Estudos de Casos e Controles , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/tratamento farmacológico , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/diagnóstico , Mieloblastina , Recidiva , Peroxidase
8.
RMD Open ; 9(4)2023 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-38056920

RESUMO

BACKGROUND: Hepatitis B virus (HBV) vaccination is recommended for non-immunised patients with rheumatic diseases starting biological disease-modifying antirheumatic drugs (bDMARDs). There is some evidence that HBV vaccination is effective in patients under conventional synthetic disease-modifying anti-rheumatic drugs (csDMARDs), but it is currently unclear whether this also applies to bDMARDs. OBJECTIVES: To assess the efficacy and safety of HBV vaccination in patients with inflammatory arthritides treated with bDMARDs. METHODS: A prospective cohort with inflammatory arthritides treated with bDMARDs, negative for anti-HBs and anti-HBc and never vaccinated for HBV was recruited. Engerix B was administered at 0, 1 and 6 months and anti-HBs was reassessed ≥1 month after last dose. Response was defined as anti-HBs≥10 IU/L and compared against vaccinated healthy controls. Disease flare, serious adverse events and immune-related disorders not previously present were recorded. RESULTS: 62 patients, most treated with TNF inhibitors (TNFi), and 38 controls were recruited. Most patients were taking csDMARDs (67.7%) and were in remission/low disease activity (59.4%). Only 20/62 patients (32.3%) had a positive response to vaccination, in comparison to 36/38 age-matched controls (94.7%, p<0.001). Response was seen in 19/51 patients treated with TNFi (37.3%) and in 1/11 (9.1%) patients treated with non-TNFi (p=0.07), including 1/6 treated with tocilizumab (16.7%). Among TNFi, response rates ranged from 4/22 (18.2%) for infliximab to 8/14 (57.1%) for etanercept. No relevant safety issues were identified. CONCLUSIONS: HBV vaccination response in patients with rheumatic diseases treated with bDMARDs was poorer than expected. Our data reinforce the recommendation for vaccination prior to starting bDMARDs.


Assuntos
Antirreumáticos , Artrite , Produtos Biológicos , Hepatite B , Doenças Reumáticas , Humanos , Estudos Prospectivos , Hepatite B/complicações , Hepatite B/prevenção & controle , Hepatite B/tratamento farmacológico , Antirreumáticos/efeitos adversos , Doenças Reumáticas/tratamento farmacológico , Doenças Reumáticas/complicações , Anticorpos Anti-Hepatite B , Vacinação , Produtos Biológicos/efeitos adversos
9.
Sci Immunol ; 8(90): eadf9988, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38100545

RESUMO

Studies of human lung development have focused on epithelial and mesenchymal cell types and function, but much less is known about the developing lung immune cells, even though the airways are a major site of mucosal immunity after birth. An unanswered question is whether tissue-resident immune cells play a role in shaping the tissue as it develops in utero. Here, we profiled human embryonic and fetal lung immune cells using scRNA-seq, smFISH, and immunohistochemistry. At the embryonic stage, we observed an early wave of innate immune cells, including innate lymphoid cells, natural killer cells, myeloid cells, and lineage progenitors. By the canalicular stage, we detected naive T lymphocytes expressing high levels of cytotoxicity genes and the presence of mature B lymphocytes, including B-1 cells. Our analysis suggests that fetal lungs provide a niche for full B cell maturation. Given the presence and diversity of immune cells during development, we also investigated their possible effect on epithelial maturation. We found that IL-1ß drives epithelial progenitor exit from self-renewal and differentiation to basal cells in vitro. In vivo, IL-1ß-producing myeloid cells were found throughout the lung and adjacent to epithelial tips, suggesting that immune cells may direct human lung epithelial development.


Assuntos
Imunidade Inata , Pulmão , Humanos , Diferenciação Celular , Células Matadoras Naturais , Células Epiteliais
10.
PLoS One ; 18(11): e0294131, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37956119

RESUMO

BACKGROUND: Adaptive thermogenesis, defined as the decrease in the energy expenditure components beyond what can be predicted by changes in body mass stores, has been studied as a possible barrier to weight loss and weight maintenance. Intermittent energy restriction (IER), using energy balance refeeds, has been pointed out as a viable strategy to reduce adaptive thermogenesis and improve weight loss efficiency (greater weight loss per unit of energy deficit), as an alternative to a continuous energy restriction (CER). Following a randomized clinical trial design, the BREAK Study aims to compare the effects of IER versus CER on body composition and in adaptive thermogenesis, and understand whether participants will successfully maintain their weight loss after 12 months. METHODS: Seventy-four women with obesity and inactive (20-45 y) will be randomized to 16 weeks of CER or IER (8x2 weeks of energy restriction interspersed with 7x1 week in energy balance). Both groups will start with 2 weeks in energy balance before energy restriction, followed by 16 weeks in energy restriction, then 8 weeks in energy balance and finally a 12-month weight maintenance phase. Primary outcomes are changes in fat-mass and adaptive thermogenesis after weight loss and weight maintenance. Secondary outcomes include weight loss, fat-free mass preservation, alterations in energy expenditure components, and changes in hormones (thyroid function, insulin, leptin, and cortisol). DISCUSSION: We anticipate that The BREAK Study will allow us to better understand adaptive thermogenesis during weight loss and weight maintenance, in women with obesity. These findings will enable evidence-based decisions for obesity treatment. TRIAL REGISTRATION: ClinicalTrials.gov: NCT05184361.


Assuntos
Restrição Calórica , Obesidade , Humanos , Feminino , Redução de Peso , Metabolismo Energético , Termogênese , Composição Corporal , Ensaios Clínicos Controlados Aleatórios como Assunto
11.
Contemp Clin Trials Commun ; 35: 101202, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37691850

RESUMO

Background: Within professional European competitions, matches can be played in extreme environmental temperatures, ranging from -5 °C to +30 °C in different countries. Furthermore, the World Cups are usually played in the summer months, when temperatures can exceed 35 °C, increasing physiological stress. Practical and cost-effective cooling strategies may be implemented to help players and referees to cope with exercising in the heat. No study has evaluated the effect of non-thermal internal cooling techniques regarding performance responses on elite football referees, so far. This study aims to analyse the effects of a menthol mouth rinse regarding physical, physiological, and perceptual performance in elite male football referees, during a 90-min football protocol in the heat. Methods: At least thirteen male football referees will be recruited to perform two intermittent football protocols, separated by no less than 7 days. After passing the eligibility criteria, the participants will be randomly assigned to 1 of 2 beverages: (1) intervention - menthol solution 0.01% and (2) placebo - noncaloric berry-flavored solution, both at room temperature. The beverages will be given before warm-up (pre-cooling) and at the half-time (per-cooling). The trials will follow a randomized counterbalanced crossover design, single blinded, and will take place in indoor facilities, with Wet Bulb Globe Temperature (WBGT) > 30 °C, at the same time of the day to control for circadian variations. Impact of the project: The results of this study are expected to determine whether mouth rinsing a menthol solution before and during a football exercise protocol performed in the heat will alter perceptual measures and help ease physiological strain and attenuate performance decrements in elite male football referees, comparing to a non-cooling strategy. Thus, we can be closer to defining nutritional strategies of internal cooling that may be an advantage for the performance of the football referees in the heat. Trial registration: www.ClinicalTrials.gov NCT05632692 registered on 20 November 2022.

12.
Front Sports Act Living ; 5: 1230969, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37637220

RESUMO

Introduction and objectives: Dietary supplements are part of the nutritional strategies frequently applied in sports performance support. With growing research on this subject and high demand from athletes, nutritionists need to keep up to date with the latest evidence and utility of dietary supplements, particularly in real-world contexts. As information about the use of dietary supplements among elite soccer players is still scarce, this work aimed to know how nutritionists working with elite soccer teams perceive and use these substances in their daily practice. Methods: A questionnaire previously used to describe nutritionists' beliefs and attitudes regarding the use of dietary supplements in a clinical context was adapted for this study. The online questionnaire was addressed to nutritionists working with elite soccer teams from six European Leagues and Brazil, between November 2022 and February 2023. Results: Overall, the participants considered themselves well-trained (76.9%), knowledgeable (95.4%), and interested in dietary supplements (95.4%). The majority (70.8%) of the participants agreed or strongly agreed to recommend dietary supplements to soccer players. Personal usage of dietary supplements was associated with recommending supplements (p < 0.001), but no relationships were found with years of experience and academic level. Discussion: Nutritionists working with elite soccer players consider the use of dietary supplements for performance-enhancement purposes and not only to compensate for nutritional deficits, which might contribute to their higher interest, training and perceived knowledge about this topic. Participants recognize players' interest in dietary supplements, and are mindful of the safety and efficacy of these products. The present study suggests that nutritionists working with elite soccer teams are among the highest prescribers of dietary supplements, although personal usage is lower than that of nutritionists working in a clinical context.

13.
Antioxidants (Basel) ; 12(7)2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37507901

RESUMO

In premature infants receiving parenteral nutrition, oxidative stress is a trigger for the development of bronchopulmonary dysplasia, which is an important factor in the development of adult lung diseases. Neonatal vitamin C and glutathione deficiency is suspected to induce permanent modification of redox metabolism favoring the development of neonatal and adult lung diseases. A total of 64 3-day-old guinea pigs were fed an oral diet that was either complete or deficient in vitamin C (VCD), cysteine (CD) (glutathione-limiting substrate) or both (DD) for 4 days. At 1 week of age, half of the animals were sacrificed while the other started a complete diet until 12 weeks of age. At 1 week, the decrease in lung GSH in all deficient groups was partially explained by the oxidation of liver methionine-adenosyltransferase. mRNA levels of kelch-like ECH-associated protein 1 (Keap1), glutathione-reductase (Gsr) and glutaredoxin-1 (Glrx) were significantly lower only in CD but not in DD. At 12 weeks, glutathione levels were increased in VCD and CD. Keap1, Gsr and Glrx mRNA were increased, while glutathione-reductase and glutaredoxin proteins were lower in CD, favoring a higher glutathionylation status. Both neonatal deficiencies result in a long-term change in glutathione metabolism that could contribute to lung diseases' development.

14.
J Int Soc Sports Nutr ; 20(1): 2236060, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37462346

RESUMO

Dietary supplements are widely used among athletes, and soccer players are no exception. Nevertheless, evidence supporting the use of dietary supplements aiming to enhance performance in soccer is somewhat contradictory, scarce, or even nonexistent. Thus, the present study aimed to systematically review and synthesize the effects of dietary supplements on athletic performance (e.g. distance covered, sprinting, jump performance) in elite soccer players. Studies enrolling highly trained, elite, and world-class soccer players using dietary supplements were searched in MEDLINE/PubMed, Web of Science, Scopus, and EBSCO databases in June 2022. In total, 1043 studies were identified, and 18 met the eligibility criteria. The studies evaluated the impacts on athletic performance of several dietary supplements, including caffeine, creatine, protein, beverages with carbohydrates and electrolytes, tart cherry juice, nitrate-rich beetroot juice, sodium bicarbonate with minerals, yohimbine, and a proprietary nutraceutical blend. Caffeine supplementation in doses between 3 and 6 mg/kg of body mass may improve jump height and sprint ability, particularly in female players, but individual response to caffeine must be considered. Creatine may improve sprint, agility, and in female players, jump performance. Protein supplementation can improve sprint and jump performance between matches, especially if protein ingested from food is not up to recommendations. Beverages containing carbohydrates and electrolytes can be used as part of the strategies to achieve carbohydrate intake during training and match-days but used alone do not benefit athletic performance. Tart cherry juice might be useful for maintaining athletic performance after matches that produce higher force loss and exercise-induced muscle damage, although polyphenols from the diet might attenuate the effects of tart cherry supplementation. Nitrate-rich beetroot concentrate can attenuate performance decrease in the days following matches. Further investigation with sodium bicarbonate alone is necessary, as supplementation protocols with elite players included other substances. Finally, the available data does not support yohimbine supplementation or the use of Resurgex Plus® to improve athletic performance in elite soccer players. Still, more well-designed research with elite soccer players is needed to improve support and advice regarding the use of dietary supplements for athletic performance enhancement.


Assuntos
Desempenho Atlético , Futebol , Humanos , Feminino , Futebol/fisiologia , Cafeína/farmacologia , Bicarbonato de Sódio , Creatina/farmacologia , Nitratos , Desempenho Atlético/fisiologia , Suplementos Nutricionais , Eletrólitos , Carboidratos
16.
Int J Mol Sci ; 24(7)2023 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-37047194

RESUMO

Niemann-Pick type C1 (NPC1) is an endolysosomal transmembrane protein involved in the export of cholesterol and sphingolipids to other cellular compartments such as the endoplasmic reticulum and plasma membrane. NPC1 loss of function is the major cause of NPC disease, a rare lysosomal storage disorder characterized by an abnormal accumulation of lipids in the late endosomal/lysosomal network, mitochondrial dysfunction, and impaired autophagy. NPC phenotypes are conserved in yeast lacking Ncr1, an orthologue of human NPC1, leading to premature aging. Herein, we performed a phosphoproteomic analysis to investigate the effect of Ncr1 loss on cellular functions mediated by the yeast lysosome-like vacuoles. Our results revealed changes in vacuolar membrane proteins that are associated mostly with vesicle biology (fusion, transport, organization), autophagy, and ion homeostasis, including iron, manganese, and calcium. Consistently, the cytoplasm to vacuole targeting (Cvt) pathway was increased in ncr1∆ cells and autophagy was compromised despite TORC1 inhibition. Moreover, ncr1∆ cells exhibited iron overload mediated by the low-iron sensing transcription factor Aft1. Iron deprivation restored the autophagic flux of ncr1∆ cells and increased its chronological lifespan and oxidative stress resistance. These results implicate iron overload on autophagy impairment, oxidative stress sensitivity, and cell death in the yeast model of NPC1.


Assuntos
Sobrecarga de Ferro , Doença de Niemann-Pick Tipo C , Humanos , Saccharomyces cerevisiae/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Ferro/metabolismo , Longevidade , Receptor 1 Desencadeador da Citotoxicidade Natural/metabolismo , Proteínas de Membrana/metabolismo , Lisossomos/metabolismo , Vacúolos/metabolismo , Autofagia , Sobrecarga de Ferro/metabolismo , Doença de Niemann-Pick Tipo C/metabolismo
17.
Int J Mol Sci ; 24(5)2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36902357

RESUMO

This Special Issue was devoted to unravelling novel aspects of yeast biology and signal transduction in numerous yet intricate basic processes [...].


Assuntos
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Transdução de Sinais/fisiologia , Proteínas de Saccharomyces cerevisiae/metabolismo
19.
J Cell Sci ; 136(1)2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36594787

RESUMO

Cdc28, the homolog of mammalian Cdk1, is a conserved key regulatory kinase for all major cell cycle transitions in yeast. We have found that defects in mitochondrial respiration (including deletion of ATP2, an ATP synthase subunit) inhibit growth of cells carrying a degron allele of Cdc28 (cdc28td) or Cdc28 temperature-sensitive mutations (cdc28-1 and cdc28-1N) at semi-permissive temperatures. Loss of cell proliferation in the atp2Δcdc28td double mutant is associated with aggravated cell cycle arrest and mitochondrial dysfunction, including mitochondrial hyperpolarization and fragmentation. Unexpectedly, in mutants defective in mitochondrial respiration, steady-state protein levels of mutant cdc28 are strongly reduced, accounting for the aggravated growth defects. Stability of Cdc28 is promoted by the Hsp90-Cdc37 chaperone complex. Our results show that atp2Δcdc28td double-mutant cells, but not single mutants, are sensitive to chemical inhibition of the Hsp90-Cdc37 complex, and exhibit reduced levels of additional Hsp90-Cdc37 client kinases, suggesting an inhibition of this complex. In agreement, overexpression of CDC37 improved atp2Δcdc28td cell growth and Cdc28 levels. Overall, our study shows that simultaneous disturbance of mitochondrial respiration and Cdc28 activity reduces the capacity of Cdc37 to chaperone client kinases, leading to growth arrest.


Assuntos
Proteínas de Ciclo Celular , Chaperonas Moleculares , Humanos , Animais , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Chaperonas Moleculares/metabolismo , Proteína Quinase CDC28 de Saccharomyces cerevisiae/genética , Proteína Quinase CDC28 de Saccharomyces cerevisiae/metabolismo , Proteínas de Choque Térmico HSP90/genética , Proteínas de Choque Térmico HSP90/metabolismo , Saccharomyces cerevisiae/metabolismo , Mitocôndrias/genética , Mitocôndrias/metabolismo , Ligação Proteica , Mamíferos/metabolismo , Chaperoninas/metabolismo , Proteína Quinase CDC2/genética , Proteína Quinase CDC2/metabolismo
20.
J Sports Med Phys Fitness ; 63(1): 53-59, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35415998

RESUMO

BACKGROUND: To analyze whether pre-exercise CHO+PRO vs. CHO intake distinctly influences running performance and metabolic biomarkers along a various of exercise intensities. METHODS: In a randomized, double blind, counterbalanced, crossover and placebo control design, 10 middle distance runners were tested in 3 occasions. After 10 h of fasting, participants ingested isovolumic beverages (0.75+0.25g·BW-1 of CHO+PRO, 1.0g·BW-1 of CHO and placebo control) 30 min before a treadmill running incremental protocol of 4 min steps until exhaustion. Venous blood was collected at fasting, 30 min after beverage ingestion and after the 3rd and 7th running steps. Oxygen uptake-related variables, including respiratory exchange ratio, heart rate, plasma glucose, insulin, glucagon, free fatty acids, blood lactate concentrations, gastrointestinal discomfort and rate of perceived exertion were measured. RESULTS: The addition of PRO to CHO had no influence on the measured variables, which did not differ between conditions along all incremental protocol intensities. The intake of CHO+PRO (compared to CHO) tended to decrease glycemia (106.5±21.3 vs. 113.6±26.5) and to increase insulinemia (14.4±15.1 vs. 12.7±10.8) at intensities close to maximum oxygen uptake. CONCLUSIONS: The addition of PRO to a pre-exercise CHO beverage had no impact on running performance and related metabolic variables at a wide spectrum of exercise intensities.


Assuntos
Consumo de Oxigênio , Corrida , Humanos , Resistência Física/fisiologia , Carboidratos da Dieta , Glicemia/metabolismo , Oxigênio , Corrida/fisiologia , Bebidas , Ácido Láctico , Método Duplo-Cego
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