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1.
Int J Geriatr Psychiatry ; 39(3): e6078, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38470426

RESUMO

OBJECTIVE: This study aimed to explore the interplay between frailty, physical function, physical activity, nutritional status, and their impact on the quality of life and depressive status in older adults with frailty. METHODS: A cross-sectional study involving 235 pre-frail/frail older adults residing in Spanish communities was conducted. Frailty was assessed using Fried's criteria, physical function was evaluated using the Short Physical Performance Battery, and physical activity levels were measured via wrist-worn accelerometers. Nutritional status was determined using the Mini-Nutritional Assessment alongside anthropometric measurements. Quality of life was gauged using the EuroQoL 5-Dimension 5-Level, while depressive status was assessed using the Yesavage 15-item Geriatric Depression Scale. Multivariate linear regression and logistic regression analyses were employed to elucidate the associations of these factors with quality of life and depression. RESULTS: Our findings revealed significant correlations between various factors and quality of life. Notably, reported fatigue (ß = -0.276, p = 0.002), performance in the 4-m gait test (ß = -0.242, p = 0.001), the score on the short version of the Mini-Nutritional Assessment (ß = 0.312, p = 0.002), and engagement in light physical activity (ß = 0.180, p = 0.023) were all found to be associated with quality of life. In terms of depressive symptoms, the Mini-Nutritional Assessment score emerged as a protective factor (Odds ratio, OR: 0.812, p < 0.001), as did participation in moderate physical activity (OR: 0.988, p = 0.028). Conversely, fatigue (OR: 3.277, p = 0.003) and a slow gait speed (OR: 1.136, p = 0.045) were identified as risk factors for depressive symptoms. CONCLUSIONS: This study underscores the detrimental association of fatigue and slow gait speed on both quality of life and depressive status among older adults with frailty. In contrast, engaging in physical activity and addressing malnutrition risk emerge as critical protective factors for enhancing quality of life and ameliorating depressive symptoms in this population. CLINICAL TRIAL REGISTRATION: This is a study that uses cross-sectional data from a trial registered at ClinicalTrials.gov (Identifier: NCT05610605).


Assuntos
Fragilidade , Estado Nutricional , Idoso , Humanos , Estudos Transversais , Depressão , Exercício Físico , Fadiga , Fenótipo , Qualidade de Vida , Ensaios Clínicos como Assunto
2.
J Clin Nurs ; 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38932443

RESUMO

BACKGROUND: The coexistence of frailty and type 2 diabetes mellitus in the older population heightens the risk of adverse events. However, research on functional and wellness factors associated with frailty in this population is limited. PURPOSE: To investigate the associations of physical performance, functional dependency, physical activity, nutritional status, sleep, self-perceived health and depression with frailty in community-dwelling older adults with coexisting frailty and type 2 diabetes mellitus. DESIGN: Cross-sectional. METHODS: The study included 123 community-dwelling older adults (73.7 ± 6.0 years) with pre-frailty/frailty and type 2 diabetes mellitus. Physical performance (Short Physical Performance Battery), functional dependency (Barthel Index and Lawton & Brody), physical activity and inactivity (GeneActiv wrist-worn accelerometer), malnutrition risk (Mini Nutritional Assessment), sleep (Pittsburgh Sleep Quality Index), self-perceived health (EuroQoL 5-Dimension 3-Level) and depression (Yesavage 15-item-Geriatric-Depression-Scale) were evaluated through personal interviews. Principal component analysis (PCA) was performed to categorize the variables into components, and logistic regressions were used to propose the best-fitted model for each component. RESULTS: The PCA identified four components: (i) physical performance, with gait speed and leg mean velocity as the main variables associated with frailty; (ii) balance, showing significant associations with monopodal balance; (iii) daily activities, with moderate to vigorous physical activity and the Lawton and Brody score as the main variables associated with frailty within this component; and (iv) wellness factors, with nutritional status, self-perceived health and depression score as the primary variables associated with frailty. CONCLUSIONS: This research underscores the significance of physical function and daily activities as protective factors against frailty in community-dwelling older adults with coexisting frailty and type 2 diabetes mellitus. The health dimension contributes both protective and risk factors, emphasizing the need for comprehensive assessments in managing frailty in this population. REPORTING METHOD: The study adhered to the STROBE checklist. PATIENT OR PUBLIC CONTRIBUTION: No patient or public contribution.

3.
J Therm Biol ; 117: 103678, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37659343

RESUMO

BACKGROUND: Infrared thermography is a growing area of interest in sports science due to the potential of skin temperature (Tsk) measurements to provide valuable information from rest to exercise. However, limited research exists on Tsk in older adults and the impact of factors such as sex and cardiorespiratory fitness (CRF) on Tsk. This study aims to investigate Tsk at rest and after acute exercise in older adults and assess whether sex or CRF influences Tsk. METHODS: Ninety-two participants (41 women, 68.48 ± 3.01 years) were examined with a thermographic camera in a conditioned room (23.02 ± 3.01 °C) at rest and after a graded protocol. The Tsk of 25 regions of interest (ROIs) were extracted and analysed. RESULTS: Men had higher overall Tsk at rest in 76% of ROIs, showing significant differences (p < 0.010) in six specific ROIs, independent of CRF. Both sexes had similar Tsk responses after graded exercise, with increases in distal parts (1.06 ± 0.50 °C), decreases in proximal parts (-0.62 ± 0.42 °C), and stable central Tsk (0.23 ± 0.59 °C). Increases in lower limb Tsk were significantly associated with CRF in men and women (ß = 0.438, p = 0.001, and ß = 0.535, p < 0.001, respectively), explaining 17% and 27% of the variance, respectively. CONCLUSIONS: This study demonstrates a sex-specific effect on resting Tsk in older adults, suggesting that sex-specific Tsk patterns should be considered when analysing Tsk in this population. Additionally, the association between increases in lower limb Tsk and CRF suggests that Tsk could be a promising predictor of CRF in older adults.

4.
J Strength Cond Res ; 37(8): 1573-1580, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-36727700

RESUMO

ABSTRACT: Costilla, M, Casals, C, Marín-Galindo, A, Sánchez-Sixto, A, Muñoz-López, A, Sañudo, B, Corral-Pérez, J, and Ponce-González, JG. Changes in muscle deoxygenation during squat exercise after 6-week resistance training with different percentages of velocity loss. J Strength Cond Res 37(8): 1573-1580, 2023-The present study compared, for the first time, the effects of 6 weeks of 20% (20VL) vs. 40% (40VL) velocity loss (VL) resistance training (RT) programs on muscle oxygen dynamics during the squat exercise. Twenty-three young men (21.4 ± 2.4 years) were randomly allocated into the 20VL group ( n = 8), 40VL group ( n = 7), or control group (CG; n = 8). The RT program consisted of 3 sets of Smith machine back squat exercise at 20VL or 40VL with a 3-minute rest between sets, twice per week for 6 weeks. Tissue oxygenation index (TOI) was measured using near-infrared spectroscopy in the vastus medialis and vastus lateralis during a squat test (8-repetition 1 m·s -1 load test), and the maximum (maxTOI) and minimum (minTOI) TOIs were measured during a 3-min recovery period. After the 6-week RT program, TOI increased significantly at the beginning of the test in both muscles (during the first 4 repetitions in the vastus lateralis and 5 repetitions in the vastus medialis) in the 20VL group ( p < 0.05), with nonsignificant changes in the 40VL group and CG. The maxTOI was significantly increased in the vastus medialis (+3.76%) and vastus lateralis (+3.97%) after the training only in the 20VL group ( p < 0.05). The minTOI in the vastus medialis reached during the test remained unchanged postintervention for both training groups, with the CG showing significantly higher values compared with the 20VL group (+14.1%; p < 0.05). In conclusion, depending on the VL reached during a squat RT program, different changes in muscle oxygen dynamics can be expected. Training at 20% of VL improves metabolic efficiency and the reoxygenation peak after the set.


Assuntos
Treinamento Resistido , Masculino , Humanos , Treinamento Resistido/métodos , Músculo Quadríceps/fisiologia , Exercício Físico/fisiologia , Terapia por Exercício , Oxigênio , Músculo Esquelético/fisiologia , Força Muscular/fisiologia
5.
J Strength Cond Res ; 36(11): 3056-3064, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34115697

RESUMO

ABSTRACT: Muñoz-López, A, Marín-Galindo, A, Corral-Pérez, J, Costilla, M, Sánchez-Sixto, A, Sañudo, B, Casals, C, and Ponce-González, JG. Effects of different velocity loss thresholds on passive contractile properties and muscle oxygenation in the squat exercise using free weights. J Strength Cond Res 36(11): 3056-3064, 2022-The current study assessed the impact between different velocity loss thresholds on changes in the muscle contractile properties and muscle oxygenation after a single resistance training (RT) session. Thirty physically active men participated in a crossover study performing 3 sets of the squat exercise at a lifted speed of ≈0.75 m·s -1 , with 2 different velocity loss thresholds: 20% (VL20) vs 40% (VL40) in a randomized order. Contractile properties of the knee extensor muscles were tested using tensiomyography. In addition, muscle oxygenation was continuously measured from baseline until the end of the exercise session. The vastus lateralis showed a significant moment by condition interaction in time delay ( p = 0.044), muscle displacement ( p = 0.001), and contraction velocity ( p = 0.007), with greater reductions in VL40. In both trainings, oxygenated hemoglobin and tissue oxygen index decreased, whereas deoxygenated hemoglobin increased (moment as the main effect, p < 0.05), but without a moment by condition interaction. VL40 showed a lower deoxygenation slope in set 1 (-0.468%·s -1 , p = 0.001) and set 3 (-0.474%·s -1 , p = 0.037) as well as higher losses in set 1 (-41.50%, p = 0.003), set 2 (-41.84%, p = 0.002), and set 3 (-62.51%, p < 0.001), compared with VL20. No differences were found in the recovery period between conditions. In conclusion, during the RT program design, coaches and athletes should consider that VL40 produces higher mechanical and neuromuscular impairments than VL20, which seems to be necessary for hypertrophy to occur; however, VL40 also produces a longer period of lower oxygen supply than VL20, which can induce fast-to-slow muscle fiber transition.


Assuntos
Força Muscular , Treinamento Resistido , Masculino , Humanos , Força Muscular/fisiologia , Estudos Cross-Over , Músculo Esquelético/fisiologia , Oxigênio , Hemoglobinas
6.
J Therm Biol ; 97: 102875, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33863439

RESUMO

Where people live and work together it is not always possible to modify the ambient temperature; ways must therefore be found that allow individuals to feel thermally comfortable in such settings. The Embr Wave® is a wrist-worn device marketed as a 'personal thermostat' that can apply a local cooling stimulus to the skin. The aim of the present study was to determine the effect of an intermittent mild cold stimulus of 25 °C for 15-20 s every 5 min over 3.5 days under free-living conditions on 1) skin temperature, 2) perception of skin temperature, 3) sleep quality and 4) resting energy expenditure (REE) in young, healthy adults. Ten subjects wore the device for 3.5 consecutive days. This intervention reduced distal skin temperature after correcting for personal ambient temperature (P < 0.05), but did not affect the subjects' the perception of skin temperature, sleep quality or REE (all P ≥ 0.051). Thus, this intermittent mild cold regime can reduce distal skin temperature, and wearing it under free-living conditions for 3.5 days does not seem to impair the perception of skin temperature and sleep quality or modify REE.


Assuntos
Temperatura Baixa , Temperatura Cutânea , Termometria/instrumentação , Adulto , Metabolismo Energético , Feminino , Humanos , Masculino , Sono , Adulto Jovem
7.
J Therm Biol ; 82: 186-196, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31128647

RESUMO

Brown adipose tissue (BAT) thermogenic activity is commonly assessed with a positron emission tomography with computed tomography scan (PET/CT). This technique has several limitations and alternative techniques are needed. Supraclavicular skin temperature measured with iButtons and infrared thermography (IRT) has been proposed as an indirect marker of BAT activity. We studied the concurrent validity of skin temperature measured with iButtons vs. IRT and the association of supraclavicular skin temperature measured with iButtons and IRT with BAT. We measured skin temperature upon a shivering threshold test with iButtons and IRT in 6 different regions in 12 participants (n = 2 men). On a separate day, we determined supraclavicular skin temperature with an iButton and IRT after 2 h of a personalized cooling protocol. Thereafter, we quantified BAT volume and activity by PET/CT. We observed that the absolute differences between the devices were statistically different from 0 (all P < 0.05) after the shivering threshold test. Moreover, we did not find any association between supraclavicular skin temperature measured with iButtons or IRT and BAT 18F-FDG activity (r = -0.213; P = 0.530 and r = -0.079; P = 0.817). However, we observed a negative association of supraclavicular skin temperature measured by IRT with BAT 18F-FDG volume (r = -0.764; P = 0.006), but not with supraclavicular skin temperature measured with iButtons (r = -0.546; P = 0.082). In light of these results, we concluded that the measurement of skin temperature obtained by iButtons and IRT are not comparable. Furthermore, it seems that supraclavicular skin temperature is not associated with BAT 18F-FDG activity, but it appears to be negatively associated with BAT 18F-FDG volume in the case of IRT.


Assuntos
Tecido Adiposo Marrom/fisiologia , Temperatura Cutânea , Termogênese , Termografia/métodos , Adolescente , Adulto , Feminino , Fluordesoxiglucose F18/metabolismo , Humanos , Raios Infravermelhos , Masculino , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Adulto Jovem
8.
Angew Chem Int Ed Engl ; 58(39): 13989-13996, 2019 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-31328855

RESUMO

Selective hydrogenation of CO2 into methanol is a key sustainable technology, where Cu/Al2 O3 prepared by surface organometallic chemistry displays high activity towards CO2 hydrogenation compared to Cu/SiO2 , yielding CH3 OH, dimethyl ether (DME), and CO. CH3 OH formation rate increases due to the metal-oxide interface and involves formate intermediates according to advanced spectroscopy and DFT calculations. Al2 O3 promotes the subsequent conversion of CH3 OH to DME, showing bifunctional catalysis, but also increases the rate of CO formation. The latter takes place 1) directly by activation of CO2 at the metal-oxide interface, and 2) indirectly by the conversion of formate surface species and CH3 OH to methyl formate, which is further decomposed into CH3 OH and CO. This study shows how Al2 O3 , a Lewis acidic and non-reducible support, can promote CO2 hydrogenation by enabling multiple competitive reaction pathways on the oxide and metal-oxide interface.

9.
J Am Chem Soc ; 140(42): 13884-13891, 2018 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-30269494

RESUMO

Methyl formate synthesis by hydrogenation of carbon dioxide in the presence of methanol offers a promising path to valorize carbon dioxide. In this work, silica-supported silver nanoparticles are shown to be a significantly more active catalyst for the continuous methyl formate synthesis than the known gold and copper counterparts, and the origin of the unique reactivity of Ag is clarified. Transient in situ and operando vibrational spectroscopy and DFT calculations shed light on the reactive intermediates and reaction mechanisms: a key feature is the rapid formation of surface chemical species in equilibrium with adsorbed carbon dioxide. Such species is assigned to carbonic acid interacting with water/hydroxyls on silica and promoting the esterification of formic acid with adsorbed methanol at the perimeter sites of Ag on SiO2 to yield methyl formate. This study highlights the importance of employing combined methodologies to verify the location and nature of active sites and to uncover fundamental catalytic reaction steps taking place at metal-support interfaces.

10.
Chemphyschem ; 18(22): 3135-3141, 2017 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-28851111

RESUMO

This article describes the main strategies to activate and convert carbon dioxide (CO2 ) into valuable chemicals over catalytic surfaces. Coherent elements such as common intermediates are identified in the different strategies and concisely discussed based on the reactivity of CO2 with the aim to understand the decisive factors for selective and efficient CO2 conversion.

11.
Farm Hosp ; 2024 Jun 20.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-38906717

RESUMO

OBJECTIVE: This research delves into the intricate interplay between antipsychotic medications and neuroprotection focusing on the S100B protein-a central player in the regulation of neuroapoptotic activity. METHOD: Blood samples were collected to assess serum S100B protein levels using an immunoassay of immunoelectrochemiluminescence. The first two samples were collected with a 3-month interval between each, and the third sample was obtained 6 months after the previous one. Changes in S100B protein levels throughout the study were assessed using Friedman's ANOVA test. This was followed by the Wilcoxon signed-rank test with Bonferroni correction to account for multiple comparisons. RESULTS: This study involved 40 patients diagnosed with severe mental disorders (34 schizophrenia, 4 schizoaffective disorder, 1 bipolar disorder, and 1 borderline personality disorder). These patients had been receiving antipsychotic treatment for an average duration of 17 years. The results revealed that the S100B protein remained within physiological levels (median values 39.0 ng/L for the first sample, median values 41.0 ng/L for the second sample, and median values 40.5 ng/L for the third sample) with no significant changes (p = 0.287), with all anti-psychotic medicaments values consistently below 50 ng/L, a lower value compared to maximum range of 105 ng/L. Importantly, there were no significant differences in S100B protein levels between patients on monotherapy and those on combination antipsychotic therapy (p = 0.873), suggesting that combination therapy did not increase neuroapoptotic activity. CONCLUSIONS: These findings provide compelling evidence for the potential neuroprotective effects of long-term antipsychotic treatment in individuals with severe mental disorders. By maintaining physiological levels of the S100B protein, antipsychotic medications may help protect against neuronal damage and dysfunction. This research contributes valuable insights into the neuroprotective mechanisms of antipsychotic drugs, enhancing our understanding of their potential benefits in the treatment of severe mental disorders.

12.
Artigo em Inglês | MEDLINE | ID: mdl-38436435

RESUMO

BACKGROUND: Frailty is associated with urinary and fecal incontinence, which are common geriatric syndromes. This study aims to identify health factors associated with incontinence in prefrail or frail older adults living in the community. METHODS: This multicenter cross-sectional study included 225 older adults (75.0 ±â€…6.4 years) with prefrailty or frailty based on the 5-component Fried phenotype. Physical function was assessed using the Short Physical Performance Battery (SPPB). Physical activity, inactivity, and sleep were estimated using a wrist-worn accelerometer. Urinary or fecal incontinence was registered using the Barthel scale (urine and bowel items). Multivariable logistic regression analyses, with age as a covariate, were conducted to identify associations of incontinence. RESULTS: In our participants, 27% presented urinary or fecal incontinence with no sex differences (p = .266). Our results showed that age, daily medication count, and number of falls in the previous year independently predicted incontinence in frail and prefrail older adults (p < .05). Some Fried's criteria, including self-reported exhaustion, gait speed, and handgrip strength, were associated with the presence of incontinence (p < .05), but not Fried's classification. The SPPB total score and its isolated variables were significantly associated with the urinary and fecal incontinence (p < .05). However, none of the accelerometer outcomes showed significant associations with incontinence status. CONCLUSIONS: According to this study, age, number of medications, and falls (but not sex) are linked to urinary and fecal incontinence in frail or prefrail older adults living in the community, recommending the assessment of physical function using the SPPB rather than estimating daily physical activity, inactivity, or sleep.


Assuntos
Incontinência Fecal , Idoso Fragilizado , Avaliação Geriátrica , Incontinência Urinária , Humanos , Masculino , Idoso , Feminino , Estudos Transversais , Incontinência Urinária/epidemiologia , Incontinência Urinária/fisiopatologia , Incontinência Fecal/epidemiologia , Avaliação Geriátrica/métodos , Idoso de 80 Anos ou mais , Fatores de Risco , Fragilidade/diagnóstico , Fragilidade/fisiopatologia , Vida Independente , Exercício Físico/fisiologia
13.
J Sci Med Sport ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-39054175

RESUMO

Monitoring of changes in skeletal muscle oxygenation during exercise has increased in recent years. Tissue oxygenation, which is related to fatigue and muscle hypertrophy, is often measured using near-infrared spectroscopy (NIRS). OBJECTIVES: This study aimed to determine the test-retest reliability of a non-portable NIRS (NIRO200Nx) during the full-squat exercise and recovery in young healthy men. DESIGN: Twenty-five male participants (21.8 ±â€¯2.6 years) were recruited for this original research. Each participant completed an 8-repetition test with a load that elicited a velocity of 1 m·s-1. The test was conducted twice, with a 48-hour washout period between sessions. METHODS: The NIRS measured the changes of oxygenated-Hemoglobin (O2Hb), deoxygenated-Hemoglobin (HHb) and Tissue Oxygenation Index (TOI) in both Vastus Lateralis and Vastus Medialis during rest, exercise, and recovery. Coefficient of Variation (CV), Standard Error Measurement (SEM) and Intraclass Correlation Coefficient (ICC) were used to evaluate the reliability of the data. Significance was set at p < 0.05. RESULTS: The results indicated that TOI had good to acceptable absolute reliability (CVTOI = 2.7-10.2 %). A good relative relativity for the overall test was found for Vastus Medialis O2Hb (ICC = 0.851), HHb (ICC = 0.852), and TOI (ICC = 0.864), and Vastus Lateralis O2Hb (ICC = 0.898), HHb (ICC = 0.899), and TOI (ICC = 0.897). CONCLUSIONS: We conclude that NIRO200Nx is a reliable instrument for measuring muscle oxygen saturation through the TOI parameter in not-to-failure dynamic resistance exercises (1 set of 8 reps against ∼40 % 1 repetition maximum). Tissue oxygenation assessment could be a new way of individualizing exercise through dynamic resistance exercises.

14.
Sleep Med ; 121: 196-202, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-39002328

RESUMO

BACKGROUND: The prevalence of sleep-related issues among older adults is a significant concern, with half of the older population reporting these problems. Consequently, strategies to improve sleep are needed for this population. This study aims to assess the effects of a health educational program on sleep behaviour among pre-frail or frail older adults residing in the community and to explore possible associations with frailty. METHODS: This randomised controlled trial (NCT05610605) included a total of 197 community-dwelling older adults with frailty/pre-frailty, divided into control (n = 88) and educational (n = 109) groups, were assessed at baseline, after the 6-month educational program (6 months), and 6 months after the intervention (12 months). The intervention comprised four group sessions and six follow-up phone calls, focusing on frailty, physical activity, dietary habits, and cognitive training. Sleep quality was measured using the Pittsburgh Sleep Quality Index (PSQI) and wrist-worn accelerometry. RESULTS: At 6 months, a significant time-by-group interaction was found for self-reported [ß = -0.449, 95%CI (-0.844, -0.053), p = 0.026] and accelerometer-measured [ß = 0.505, 95%CI (0.085, 0.926), p = 0.019] sleep efficiency, showing improved sleep efficiency in the intervention group vs. controls. A significant time-by-group interaction at 6 months was noted for sleep awakenings [ß = -0.402, 95%CI (-0.825, -0.020), p = 0.047]. The educational program led to a significant decrease in awakenings, while the control group experienced an increase. The change in the number of awakenings (Rs = 0.183, p = 0.020) at 6 months was significantly associated with changes in frailty. Moreover, a significant time-by-group interaction was reported at the 12-month assessment [ß = -0.449, 95%CI (-0.844, -0.053), p = 0.026] for self-reported sleep quality, indicating better results in the intervention group compared to controls. CONCLUSION: The educational program improved sleep quality and sleep efficiency while reducing the number of awakenings per night among community-dwelling frail older adults, offering a practical approach to addressing sleep-related challenges in this demographic.

15.
J Appl Physiol (1985) ; 136(1): 79-88, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37969081

RESUMO

It is well known that exercise efficiency declines at intensities above the lactate threshold, yet the underlying mechanisms are poorly understood. Some have suggested it is due to a decline in mitochondrial efficiency, but this is difficult to examine in vivo. Therefore, the aim of the current study was to examine how changes in temperature and pH, mimicking those that occur during exercise, affect mitochondrial efficiency in skeletal muscle mitochondria. This study was performed on quadriceps muscle of 20 wild-type mice. Muscle tissue was dissected and either permeabilized (n = 10) or homogenized for isolation of mitochondria (n = 10), and oxidative phosphorylation capacity and P/O ratio were assessed using high-resolution respirometry. Samples from each muscle were analyzed in both normal physiological conditions (37°C, pH 7.4), decreased pH (6.8), increased temperature (40°C), and a combination of both. The combination of increased temperature and decreased pH resulted in a significantly lower P/O ratio, mirrored by an increase in leak respiration and a decrease in respiratory control ratio (RCR), in isolated mitochondria. In permeabilized fibers, RCR and leak were relatively unaffected, though a main effect of temperature was observed. Oxidative phosphorylation capacity was unaffected by changes in pH and temperature in both isolated mitochondria and permeabilized fibers. These results indicate that exercise-like changes in temperature and pH lead to impaired mitochondrial efficiency. These findings offer some degree of support to the concept of decreased mitochondrial efficiency during exercise, and may have implications for the assessment of mitochondrial function related to exercise.NEW & NOTEWORTHY To the best of our knowledge, this is the first study to examine the effects of combined changes in temperature and pH, mimicking intramuscular alterations during exercise. Our findings suggest that mitochondrial efficiency is impaired during exercise of moderate to high intensity, which could be a possible mechanism contributing to the decline in exercise efficiency at intensities above the lactate threshold.


Assuntos
Mitocôndrias Musculares , Mitocôndrias , Camundongos , Animais , Temperatura , Mitocôndrias Musculares/metabolismo , Mitocôndrias/metabolismo , Músculo Esquelético/metabolismo , Concentração de Íons de Hidrogênio , Lactatos/metabolismo , Consumo de Oxigênio/fisiologia
16.
Artigo em Inglês | MEDLINE | ID: mdl-36833817

RESUMO

This study aims to evaluate the differences in body composition, physical function, and physical activity between pre-frail/frail older adults and to detect risk and protective factors against frailty and physical frailty. Fried's criteria for frailty and physical frailty using the short-performance physical battery (SPPB) were measured in 179 older participants (75.3 ± 6.4 years old). Body weight, height, and waist, arm, and leg circumferences were obtained as body composition variables. Daily accelerometer outcomes (physical activity and inactivity) were obtained. Pre-frail participants showed overall better physical function and spent more time in physical activity and less time in long inactivity periods than frail participants (p < 0.05). Risk frailty factors were higher waist perimeter (Odds Ratio [OR]: 1.032, 95%CI: 1.003-1.062), low leg performance (OR: 1.025, 95%CI: 1.008-1.043), and inactivity periods longer than 30 min (OR:1.002, 95%CI: 1.000-1.005). Protective factors were standing balance (OR:0.908, 95%CI: 0.831-0.992) and SPPB score (OR: 0.908, 95%CI: 0.831-0.992) for frailty, handgrip strength (OR: 0.902, 95%CI: 0.844-0.964) for physical frailty, and light (OR: 0.986, 95%CI: 0.976-0.996) and moderate-to-vigorous (OR: 0.983, 95%CI: 0.972-0.996) physical activity for both. Our findings suggest that handgrip strength, balance, and physical activity are protective frailty factors and can be monitored in pre-frail older adults. Moreover, poor lower body performance and long inactivity periods are frailty risk factors, which highlights their importance in frailty assessment.


Assuntos
Idoso Fragilizado , Fragilidade , Humanos , Idoso , Idoso de 80 Anos ou mais , Fragilidade/diagnóstico , Força da Mão , Fatores de Proteção , Peso Corporal , Avaliação Geriátrica
17.
Nutrients ; 15(9)2023 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-37432153

RESUMO

The FTO rs9939609 gene, which presents three polymorphisms (AA, AT, and TT), has been associated with the development of obesity through an increased fat accumulation; however, the associations of the gene with other physiological mechanisms, such as appetite or fat oxidation, are still unclear. Therefore, this study aims to evaluate the influence of the FTO rs9939609 gene on different obesity-related factors in young adults. The FTO rs9939609 polymorphism was genotyped in 73 participants (28 women, 22.27 ± 3.70 years). Obesity-related factors included dietary assessment, physical activity expenditure, body composition, appetite sensation, resting metabolic rate, maximal fat oxidation during exercise (MFO), and cardiorespiratory fitness. Our results showed that TT allele participants expressed higher values of hunger (p = 0.049) and appetite (p = 0.043) after exercising compared to the AT allele group. Moreover, the TT allele group showed significantly higher values of MFO (p = 0.031) compared to the AT group, regardless of sex and body mass index. Thus, our results suggest that the FTO rs9939609 gene has an influence on appetite, hunger, and fat oxidation during exercise, with TT allele participants showing significantly higher values compared to the AT allele group. These findings may have practical applications for weight loss and exercise programs.


Assuntos
Apetite , Fome , Feminino , Adulto Jovem , Humanos , Apetite/genética , Alelos , Genótipo , Obesidade/genética , Dioxigenase FTO Dependente de alfa-Cetoglutarato/genética
18.
Artigo em Inglês | MEDLINE | ID: mdl-36673654

RESUMO

This study aims to analyse sex-specific associations of physical activity and sedentary behaviour with oxidative stress and inflammatory markers in a young-adult population. Sixty participants (21 women, 22.63 ± 4.62 years old) wore a hip accelerometer for 7 consecutive days to estimate their physical activity and sedentarism. Oxidative stress (catalase, superoxide dismutase, glutathione peroxidase, glutathione, malondialdehyde, and advanced oxidation protein products) and inflammatory (tumour necrosis factor-alpha and interleukin-6) markers were measured. Student t-tests and single linear regressions were applied. The women presented higher catalase activity and glutathione concentrations, and lower levels of advanced protein-oxidation products, tumour necrosis factor-alpha, and interleukin-6 than the men (p < 0.05). In the men, longer sedentary time was associated with lower catalase activity (ß = −0.315, p = 0.04), and longer sedentary breaks and higher physical-activity expenditures were associated with malondialdehyde (ß = −0.308, p = 0.04). Vigorous physical activity was related to inflammatory markers in the women (tumour necrosis factor-alpha, ß = 0.437, p = 0.02) and men (interleukin−6, ß = 0.528, p < 0.01). In conclusion, the women presented a better redox and inflammatory status than the men; however, oxidative-stress markers were associated with physical activity and sedentary behaviours only in the men. In light of this, women could have better protection against the deleterious effect of sedentarism but a worse adaptation to daily physical activity.


Assuntos
Comportamento Sedentário , Fator de Necrose Tumoral alfa , Masculino , Humanos , Feminino , Adulto Jovem , Adolescente , Adulto , Catalase , Interleucina-6 , Exercício Físico , Estresse Oxidativo , Antioxidantes , Malondialdeído , Glutationa , Acelerometria
19.
Nutrients ; 15(11)2023 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-37299591

RESUMO

It is unknown how plasma leptin affects fat oxidation depending on sex in young adults. Therefore, the present cross-sectional study aimed to examine the associations of plasma leptin with resting fat oxidation (RFO), maximal fat oxidation during exercise (MFO), and insulin sensitivity, considering the different responses in men and women, and the mediating role of fatness and cardiorespiratory fitness (CRF). Sixty-five young adults (22.5 ± 4.3 years; body mass index = 25.2 ± 4.7 kg·m-2, 23 females) participated in this study. Fasting plasma glucose, insulin, and leptin were analyzed. Variables related to insulin resistance (HOMA1-IR, HOMA2-IR), secretion (HOMA-%ß), and sensitivity (HOMA-%S, QUICKI) were computed. RFO and MFO were determined through indirect calorimetry. A peak oxygen uptake (VO2peak) test was performed until exhaustion after the MFO test. The MFO was relativized to body mass (MFO-BM) and the legs' lean mass divided by the height squared (MFO-LI). In men, leptin was negatively associated with MFO-BM and positively with HOMA-%ß (p ≤ 0.02 in both). In women, leptin was positively associated with RFO and QUICKI, and negatively with MFO-BM (p < 0.05 in all). The association between leptin and MFO was mediated by CRF (p < 0.05), but not by fat mass (p > 0.05). Plasma leptin is associated with fat oxidation and insulin secretion/sensitivity, with different responses within each sex. The association between leptin and fat oxidation is mediated by cardiorespiratory fitness.


Assuntos
Resistência à Insulina , Leptina , Masculino , Humanos , Feminino , Adulto Jovem , Estudos Transversais , Teste de Esforço , Tecido Adiposo
20.
Front Aging Neurosci ; 15: 1232460, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37790284

RESUMO

Introduction: This study aims to investigate the health factors associated with cognitive frailty in frail and pre-frail older adults living in the community. Methods: A total of 233 older adults meeting Fried's criteria for pre-frailty or frailty were included. Cognitive status was evaluated using the Short Portable Mental Status Questionnaire. Health factors encompassed nutritional status (evaluated using the Mini Nutritional Assessment tool, body mass index, and waist, arm, and leg circumferences), physical function (assessed with the Short Physical Performance Battery), quality of life (measured with the total index of the EuroQoL 5-Dimension 5-Level questionnaire - EQoL-Index -, and the Visual-Analogue Scale - QoL-VAS - for today's health state), as well as sleep, physical activity, and inactivity estimated through wrist-worn accelerometers. Multivariable logistic regression analyses were conducted to identify potential predictors of cognitive frailty, considering age as a confounding factor. Results: Cognitive frail participants exhibited advanced age, heightened self-reported exhaustion, diminished overall physical performance, reduced leg perimeter, decreased engagement in moderate-to-vigorous physical activity, and higher levels of inactivity (all p<0.05). However, after adjusting for age, only QoL-VAS emerged as a cognitive frailty risk factor (Odds ratio: 1.024), while the EQoL-Index, calf perimeter, and levels of moderate-to-vigorous physical activity were identified as protective factors (Odds ratios: 0.025, 0.929, and 0.973, respectively). Discussion: This study highlights the complex relationship between non-modifiable factors such as age, and modifiable factors including quality of life, nutritional status, and physical activity in the development of cognitive frailty among older adults with a frailty phenotype living in the community.

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