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1.
Clin EEG Neurosci ; 53(1): 45-53, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34558322

RESUMO

Introduction and aim: A proportion of patients diagnosed with genetic generalized epilepsy (GGE) experience eye-closure sensitivity (ECS), the underlying pathogenesis of which is unknown. In this study, we compare magnetic resonance spectroscopy (MRS) findings of healthy volunteers with patients diagnosed with GGE, with and without ECS, to detect possible explanatory differences between groups. Materials and methods: A total of 33 patients diagnosed with GGE: 17 with ECS and 16 without, and 12 healthy volunteers are included. MRS measurements of N-acetyl-aspartate (NAA), choline (Cho), and creatine (Cr) were made of bilateral occipital lobes and thalamus, and values of patients with GGE were compared with those of normal controls, and within subgroups with different clinical variables, using appropriate statistical tests. Results: Left occipital NAA and NAA/Cr levels were found to be significantly higher in the ECS group than in the control group. In the ECS epilepsy group, a significant moderate positive correlation was noted between left thalamic Cr and duration of drug therapy (r = .539, P = .047) and left thalamic Cr and age at epilepsy onset (r = .564, P = .036). Additionally, left thalamic NAA and NAA/Cr levels were observed to be lower in GGE patients compared to healthy subjects, although not to a statistically significant degree. Conclusion:The differences in MRS-measurable metabolites in the left occipital lobe in those with ECS epilepsy suggest an association between the ECS mechanism and the left occipital lobe. Our results also support the multifocal thalamocortical pathway disorder in the pathophysiology of GGE based on the observation of cellular dysfunction in the thalamus.


Assuntos
Eletroencefalografia , Epilepsia Generalizada , Creatina , Humanos , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética
2.
J Sports Med Phys Fitness ; 61(9): 1219-1225, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34610729

RESUMO

BACKGROUND: Creatine supplementation, in close proximity to resistance training sessions, may be an important strategy to augment muscle accretion and strength. The purpose of this study was to examine the effects of creatine supplementation immediately before compared to immediately after unilateral resistance training on hypertrophy and strength. METHODS: Using a counter-balanced, double-blind, repeated measures within-subject design, ten recreationally active participants (7 males; 3 females; age: 23±5 years; height: 174±9 cm; body mass: 73.5±9.7 kg) were randomized to supplement with creatine monohydrate (0.1 g/kg of body mass) immediately before and placebo immediately after training one side of the body and placebo immediately before and creatine immediately after training the other side of the body on alternate days. Resistance training consisted of elbow flexion and knee extension (3-6 sets at 80% 1-repetition maximum [1-RM]) for 8 weeks. Prior to and following training, muscle thickness (elbow flexors and leg extensors; ultrasonography) and strength (1-RM for the elbow flexors and knee extensors) was assessed. RESULTS: There was a significant increase over time for muscle thickness, strength, and relative strength (P<0.01), with no differences between creatine ingestion strategies. Total training volume performed was similar between conditions (P=0.56). CONCLUSIONS: Creatine supplementation, immediately before or immediately after unilateral resistance training, produces similar gains in muscle hypertrophy and strength in young adults.


Assuntos
Creatina , Treinamento de Força , Adolescente , Adulto , Suplementos Nutricionais , Feminino , Humanos , Hipertrofia , Masculino , Força Muscular , Músculo Esquelético , Adulto Jovem
3.
Emerg Med Clin North Am ; 39(4): 733-744, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34600634

RESUMO

Abdominal pain is one of the most common presenting complaints to the emergency department (ED). More often than not, some degree of laboratory testing is used to narrow the differential diagnosis based on the patient's history and examination. Ordering practices are often guided by evidence, habit, consulting services, and institutional/regional culture. This review highlights relevant laboratory studies that may be ordered in the ED, as well as commentary on indications and diagnostic value of these tests.


Assuntos
Dor Abdominal/etiologia , Líquido Ascítico/química , Biomarcadores/análise , Contagem de Células Sanguíneas , Sedimentação Sanguínea , Nitrogênio da Ureia Sanguínea , Proteína C-Reativa/análise , Creatina/sangue , Eletrólitos , Serviço Hospitalar de Emergência , Fezes/microbiologia , Fezes/parasitologia , Humanos , Ácido Láctico/sangue , Testes de Função Hepática , Testes de Função Pancreática , Pró-Calcitonina/sangue
4.
Mol Med ; 27(1): 129, 2021 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-34663207

RESUMO

BACKGROUND: Host inflammation contributes to determine whether SARS-CoV-2 infection causes mild or life-threatening disease. Tools are needed for early risk assessment. METHODS: We studied in 111 COVID-19 patients prospectively followed at a single reference Hospital fifty-three potential biomarkers including alarmins, cytokines, adipocytokines and growth factors, humoral innate immune and neuroendocrine molecules and regulators of iron metabolism. Biomarkers at hospital admission together with age, degree of hypoxia, neutrophil to lymphocyte ratio (NLR), lactate dehydrogenase (LDH), C-reactive protein (CRP) and creatinine were analysed within a data-driven approach to classify patients with respect to survival and ICU outcomes. Classification and regression tree (CART) models were used to identify prognostic biomarkers. RESULTS: Among the fifty-three potential biomarkers, the classification tree analysis selected CXCL10 at hospital admission, in combination with NLR and time from onset, as the best predictor of ICU transfer (AUC [95% CI] = 0.8374 [0.6233-0.8435]), while it was selected alone to predict death (AUC [95% CI] = 0.7334 [0.7547-0.9201]). CXCL10 concentration abated in COVID-19 survivors after healing and discharge from the hospital. CONCLUSIONS: CXCL10 results from a data-driven analysis, that accounts for presence of confounding factors, as the most robust predictive biomarker of patient outcome in COVID-19.


Assuntos
COVID-19/diagnóstico , Quimiocina CXCL10/sangue , Doença da Artéria Coronariana/diagnóstico , Diabetes Mellitus/diagnóstico , Hipertensão/diagnóstico , Biomarcadores/sangue , Proteína C-Reativa/metabolismo , COVID-19/sangue , COVID-19/imunologia , COVID-19/mortalidade , Comorbidade , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/imunologia , Doença da Artéria Coronariana/mortalidade , Creatina/sangue , Diabetes Mellitus/sangue , Diabetes Mellitus/imunologia , Diabetes Mellitus/mortalidade , Feminino , Hospitalização , Humanos , Hipertensão/sangue , Hipertensão/imunologia , Hipertensão/mortalidade , Imunidade Humoral , Imunidade Inata , Inflamação , Unidades de Terapia Intensiva , L-Lactato Desidrogenase/sangue , Contagem de Leucócitos , Linfócitos/imunologia , Linfócitos/patologia , Masculino , Pessoa de Meia-Idade , Neutrófilos/imunologia , Neutrófilos/patologia , Prognóstico , Estudos Prospectivos , Estudos Retrospectivos , SARS-CoV-2 , Índice de Gravidade de Doença , Análise de Sobrevida
5.
Cochrane Database Syst Rev ; 10: CD012649, 2021 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-34661903

RESUMO

BACKGROUND: Arsenic is a common environmental toxin. Exposure to arsenic (particularly its inorganic form) through contaminated food and drinking water is an important public health burden worldwide, and is associated with increased risk of neurotoxicity, congenital anomalies, cancer, and adverse neurodevelopment in children. Arsenic is excreted following methylation reactions, which are mediated by folate. Provision of folate through folic acid supplements could facilitate arsenic methylation and excretion, thereby reducing arsenic toxicity. OBJECTIVES: To assess the effects of provision of folic acid (through fortified foods or supplements), alone or in combination with other nutrients, in lessening the burden of arsenic-related health outcomes and reducing arsenic toxicity in arsenic-exposed populations. SEARCH METHODS: In September 2020, we searched CENTRAL, MEDLINE, Embase, 10 other international databases, nine regional databases, and two trials registers. SELECTION CRITERIA: Randomised controlled trials (RCTs) and quasi-RCTs comparing the provision of folic acid (at any dose or duration), alone or in combination with other nutrients or nutrient supplements, with no intervention, placebo, unfortified food, or the same nutrient or supplements without folic acid, in arsenic-exposed populations of all ages and genders. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by Cochrane. MAIN RESULTS: We included two RCTs with 822 adults exposed to arsenic-contaminated drinking water in Bangladesh. The RCTs compared 400 µg/d (FA400) or 800 µg/d (FA800) folic acid supplements, given for 12 or 24 weeks, with placebo. One RCT, a multi-armed trial, compared FA400 plus creatine (3 g/d) to creatine alone. We judged both RCTs at low risk of bias in all domains. Due to differences in co-intervention, arsenic exposure, and participants' nutritional status, we could not conduct meta-analyses, and therefore, provide a narrative description of the data. Neither RCT reported on cancer, all-cause mortality, neurocognitive function, or congenital anomalies. Folic acid supplements alone versus placebo Blood arsenic. In arsenic-exposed individuals, FA likely reduces blood arsenic concentrations compared to placebo (2 studies, 536 participants; moderate-certainty evidence). For folate-deficient and folate-replete participants who received arsenic-removal water filters as a co-intervention, FA800 reduced blood arsenic levels more than placebo (percentage change (%change) in geometric mean (GM) FA800 -17.8%, 95% confidence intervals (CI) -25.0 to -9.8; placebo GM -9.5%, 95% CI -16.5 to -1.8; 1 study, 406 participants). In one study with 130 participants with low baseline plasma folate, FA400 reduced total blood arsenic (%change FA400 mean (M) -13.62%, standard error (SE) ± 2.87; placebo M -2.49%, SE ± 3.25), and monomethylarsonic acid (MMA) concentrations (%change FA400 M -22.24%, SE ± 2.86; placebo M -1.24%, SE ± 3.59) more than placebo. Inorganic arsenic (InAs) concentrations reduced in both groups (%change FA400 M -18.54%, SE ± 3.60; placebo M -10.61%, SE ± 3.38). There was little to no change in dimethylarsinic acid (DMA) in either group. Urinary arsenic. In arsenic-exposed individuals, FA likely reduces the proportion of total urinary arsenic excreted as InAs (%InAs) and MMA (%MMA) and increases the proportion excreted as DMA (%DMA) to a greater extent than placebo (2 studies, 546 participants; moderate-certainty evidence), suggesting that FA enhances arsenic methylation. In a mixed folate-deficient and folate-replete population (1 study, 352 participants) receiving arsenic-removal water filters as a co-intervention, groups receiving FA had a greater decrease in %InAs (within-person change FA400 M -0.09%, 95% CI -0.17 to -0.01; FA800 M -0.14%, 95% CI -0.21 to -0.06; placebo M 0.05%, 95% CI 0.00 to 0.10), a greater decrease in %MMA (within-person change FA400 M -1.80%, 95% CI -2.53 to -1.07; FA800 M -2.60%, 95% CI -3.35 to -1.85; placebo M 0.15%, 95% CI -0.37 to 0.68), and a greater increase in %DMA (within-person change FA400 M 3.25%, 95% CI 1.81 to 4.68; FA800 M 4.57%, 95% CI 3.20 to 5.95; placebo M -1.17%, 95% CI -2.18 to -0.17), compared to placebo. In 194 participants with low baseline plasma folate, FA reduced %InAs (%change FA400 M -0.31%, SE ± 0.04; placebo M -0.13%, SE ± 0.04) and %MMA (%change FA400 M -2.6%, SE ± 0.37; placebo M -0.71%, SE ± 0.43), and increased %DMA (%change FA400 M 5.9%, SE ± 0.82; placebo M 2.14%, SE ± 0.71), more than placebo. Plasma homocysteine: In arsenic-exposed individuals, FA400 likely reduces homocysteine concentrations to a greater extent than placebo (2 studies, 448 participants; moderate-certainty evidence), in the mixed folate-deficient and folate-replete population receiving arsenic-removal water filters as a co-intervention (%change in GM FA400 -23.4%, 95% CI -27.1 to -19.5; placebo -1.3%, 95% CI -5.3 to 3.1; 1 study, 254 participants), and participants with low baseline plasma folate (within-person change FA400 M -3.06 µmol/L, SE ± 3.51; placebo M -0.05 µmol/L, SE ± 4.31; 1 study, 194 participants). FA supplements plus other nutrient supplements versus nutrient supplements alone In arsenic-exposed individuals who received arsenic-removal water filters as a co-intervention, FA400 plus creatine may reduce blood arsenic concentrations more than creatine alone (%change in GM FA400 + creatine -14%, 95% CI -22.2 to -5.0; creatine -7.0%, 95% CI -14.8 to 1.5; 1 study, 204 participants; low-certainty evidence); may not change urinary arsenic methylation indices (FA400 + creatine: %InAs M 13.2%, SE ± 7.0; %MMA M 10.8, SE ± 4.1; %DMA M 76, SE ± 7.8; creatine: %InAs M 14.8, SE ± 5.5; %MMA M 12.8, SE ± 4.0; %DMA M 72.4, SE ±7.6; 1 study, 190 participants; low-certainty evidence); and may reduce homocysteine concentrations to a greater extent (%change in GM FA400 + creatinine -21%, 95% CI -25.2 to -16.4; creatine -4.3%, 95% CI -9.0 to 0.7; 1 study, 204 participants; low-certainty evidence) than creatine alone. AUTHORS' CONCLUSIONS: There is moderate-certainty evidence that FA supplements may benefit blood arsenic concentration, urinary arsenic methylation profiles, and plasma homocysteine concentration versus placebo. There is low-certainty evidence that FA supplements plus other nutrients may benefit blood arsenic and plasma homocysteine concentrations versus nutrients alone. No studies reported on cancer, all-cause mortality, neurocognitive function, or congenital anomalies. Given the limited number of RCTs, more studies conducted in diverse settings are needed to assess the effects of FA on arsenic-related health outcomes and arsenic toxicity in arsenic-exposed adults and children.


Assuntos
Arsênio , Adulto , Criança , Creatina , Suplementos Nutricionais , Ácido Fólico , Alimentos Fortificados , Humanos
7.
J Int Soc Sports Nutr ; 18(1): 60, 2021 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-34503541

RESUMO

BACKGROUND: Numerous studies have demonstrated the efficacy of creatine supplementation for improvements in exercise performance. Few studies, however, have examined the effects of phosphocreatine supplementation on exercise performance. Furthermore, while polyphenols have antioxidant and anti-inflammatory properties, little is known regarding the influence of polyphenol supplementation on muscular strength, power, and endurance. Thus, the purpose of the present study was to compare the effects of 28 days of supplementation with phosphocreatine disodium salts plus blueberry extract (PCDSB), creatine monohydrate (CM), and placebo on measures of muscular strength, power, and endurance. METHODS: Thirty-three men were randomly assigned to consume either PCDSB, CM, or placebo for 28 days. Peak torque (PT), average power (AP), and percent decline for peak torque (PT%) and average power (AP%) were assessed from a fatigue test consisting of 50 maximal, unilateral, isokinetic leg extensions at 180°·s- 1 before and after the 28 days of supplementation. Individual responses were assessed to examine the proportion of subjects that exceeded a minimal important difference (MID). RESULTS: The results demonstrated significant (p < 0.05) improvements in PT for the PCDSB and CM groups from pre- (99.90 ± 22.47 N·m and 99.95 ± 22.50 N·m, respectively) to post-supplementation (119.22 ± 29.87 N·m and 111.97 ± 24.50 N·m, respectively), but no significant (p = 0.112) change for the placebo group. The PCDSB and CM groups also exhibited significant improvements in AP from pre- (140.18 ± 32.08 W and 143.42 ± 33.84 W, respectively) to post-supplementation (170.12 ± 42.68 W and 159.78 ± 31.20 W, respectively), but no significant (p = 0.279) change for the placebo group. A significantly (p < 0.05) greater proportion of subjects in the PCDSB group exceeded the MID for PT compared to the placebo group, but there were no significant (p > 0.05) differences in the proportion of subjects exceeding the MID between the CM and placebo groups or between the CM and PCDSB groups. CONCLUSIONS: These findings indicated that for the group mean responses, 28 days of supplementation with both PCDSB and CM resulted in increases in PT and AP. The PCDSB, however, may have an advantage over CM when compared to the placebo group for the proportion of individuals that respond favorably to supplementation with meaningful increases in muscular strength.


Assuntos
Força Muscular/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Fosfocreatina/farmacologia , Resistência Física/efeitos dos fármacos , Extratos Vegetais/farmacologia , Mirtilos Azuis (Planta)/química , Creatina , Suplementos Nutricionais , Método Duplo-Cego , Humanos , Masculino , Torque , Adulto Jovem
8.
Bratisl Lek Listy ; 122(10): 708-714, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34570571

RESUMO

OBJECTIVE: In this study, we analysed the results of magnetic resonance spectroscopy (MRS) in the patients with gliomas, including the error rate, MRS parameters variability, correlations with gene mutations and overall usefulness for clinical practice. MATERIAL AND METHODS: Eighty patients with glial tumours were examined by multiparametric MRI completed with single voxel MRS, as one group, then as two separate groups according to progression of the disease after the initial surgery. The error rate between the groups, MRS parameters variability, hazard ratios and correlations between metabolites, genetic markers and tumour grade were all analysed. RESULTS: Variability in Cho/Cr(h) was significantly higher in the group with a disease progression (p = 0.044). In the patients with a stable disease, strong significant negative correlations between Cho/Cr and Cho/NAA with p53 mutation (-0.945 and -0.812 respectively, p < 0.05) and between Cho/Cr and IDH1, 2 mutation (-0.796, p < 0.05) were found. In the patients with tumour progression, a significant positive correlation of NAA/Cr with 1p19q codeletion (0.486, p < 0.05) and of Cho/Cr and Cho/NAA values with p53 mutation (0.477 and 0.416, p < 0.05) were identified. Tumour grade positively correlated with Cho/Cr values (0.304, p = 0.02) in the whole patient group. CONCLUSION: MRS brings an added value to multiparametric MRI evaluation of brain tumours in the patient follow-up after an initial surgery, especially in ambiguous findings (Tab. 5, Fig. 2, Ref. 29).


Assuntos
Neoplasias Encefálicas , Glioma , Ácido Aspártico , Encéfalo , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/genética , Colina , Creatina , Glioma/diagnóstico por imagem , Glioma/genética , Humanos , Espectroscopia de Ressonância Magnética
9.
J Food Biochem ; 45(10): e13916, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34472118

RESUMO

Exercise-induced muscle damage (EIMD) causes increased soreness, impaired function of muscles, and reductions in muscle force. Accumulating evidence suggests the beneficial effects of creatine on EIMD. Nevertheless, outcomes differ substantially across various articles. The main aim of this meta-analysis was to evaluate the effect of creatine on recovery following EIMD. Medline, Embase, Cochrane Library, Scopus, and Google Scholar were systematically searched up to March 2021. The Cochrane Collaboration tool for examining the risk of bias was applied for assessing the quality of studies. Weighted mean difference (WMD), 95% confidence interval (CI), and random-effects model, were applied for estimating the overall effect. Between studies, heterogeneity was examined using the chi-squared and I2 statistics. Nine studies met the inclusion criteria. Pooled data showed that creatine significantly reduced creatine kinase (CK) concentration overall (WMD = -30.94; 95% CI: -53.19, -8.69; p = .006) and at three follow-up times (48, 72, and 96 hr) in comparison with placebo. In contrast, effects were not significant in lactate dehydrogenase (LDH) concentration overall (WMD = -5.99; 95% CI: -14.49, 2.50; p = .167), but creatine supplementation leaded to a significant reduction in LDH concentrations in trials with 48 hr measurement of LDH. The current data indicate that creatine consumption is better than rest after diverse forms of damaging and exhaustive exercise or passive recovery. The benefits relate to a decrease in muscle damage indices and improved muscle function because of muscle power loss after exercise. PRACTICAL APPLICATIONS: Creatine supplementation would be effective in reducing the immediate muscle damage that happens <24, 24, 48, 72, and 96 hr post-exercise. In the current meta-analysis, the positive effects of creatine could cause a decrease in CK concentration overall. But, due to high heterogeneity and the medium risk of bias for articles, we suggest that these results are taken into account and the facts are interpreted with caution by the readers.


Assuntos
Creatina , Mialgia , Suplementos Nutricionais , Humanos , Músculos , Mialgia/tratamento farmacológico , Mialgia/etiologia , Ensaios Clínicos Controlados Aleatórios como Assunto
10.
J Appl Physiol (1985) ; 131(4): 1241-1250, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34473575

RESUMO

Due to the invasiveness of a muscle biopsy, there is fragmentary information on the existence and possible origin of a sexual dimorphism in the skeletal muscle concentrations of the energy delivery-related metabolites carnosine, creatine, and carnitine. As these metabolites can be noninvasively monitored by proton magnetic resonance spectroscopy, this technique offers the possibility to investigate if sexual dimorphisms are present in an adult reference population and if these dimorphisms originated during puberty using a longitudinal design. Concentrations of carnosine, creatine, and carnitine were examined using proton magnetic resonance spectroscopy in the soleus and gastrocnemius muscles of an adult reference population of female (n = 50) and male adults (n = 50). For the longitudinal follow-up over puberty, 29 boys and 28 girls were scanned prepuberty. Six years later, 24 boys and 24 girls were rescanned postpuberty. A sexual dimorphism was present in carnosine and creatine, but not carnitine, in the adult reference population. Carnosine was 28.5% higher in the gastrocnemius (P < 0.001) and carnosine and creatine were respectively 19.9% (P < 0.001) and 18.2% (P < 0.001) higher in the soleus of male when compared with female adults. Through puberty, carnosine increased more in male subjects compared with female subjects, both in the gastrocnemius (+10.43% and -10.83%, respectively; interaction effect: P = 0.002) and in the soleus (+24.30% and +5.49%, respectively; interaction effect: P = 0.012). No significant effect of puberty was found in either creatine (interaction effect: P = 0.307) or carnitine (interaction effect: P = 0.066). A sexual dimorphism in the adult human muscle is present in carnosine and creatine, but not in carnitine.NEW & NOTEWORTHY This is the first study to investigate sexual dimorphisms in skeletal muscle carnosine, creatine, and carnitine concentrations in a substantial adult reference population (n = 100). A sexual dimorphism is present in both carnosine and creatine at adult age. The origin of the sexual dimorphisms is investigated using a longitudinal design over puberty in 24 males and 24 females. The sexual dimorphism in carnosine originated partly during puberty for carnosine, but not for creatine.


Assuntos
Carnosina , Adulto , Carnitina , Creatina , Feminino , Seguimentos , Humanos , Masculino , Músculo Esquelético , Puberdade
12.
Nutrients ; 13(7)2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34371916

RESUMO

White adipose tissue (WAT) is a dynamic endocrine organ that can play a significant role in thermoregulation. WAT has the capacity to adopt structural and functional characteristics of the more metabolically active brown adipose tissue (BAT) and contribute to non-shivering thermogenesis under specific stimuli. Non-shivering thermogenesis was previously thought to be uncoupling protein 1 (UCP1)-dependent however, recent evidence suggests that UCP1-independent mechanisms of thermogenesis exist. Namely, futile creatine cycling has been identified as a contributor to WAT thermogenesis. The purpose of this study was to examine the efficacy of creatine supplementation to alter mitochondrial markers as well as adipocyte size and multilocularity in inguinal (iWAT), gonadal (gWAT), and BAT. Thirty-two male and female Sprague-Dawley rats were treated with varying doses (0 g/L, 2.5 g/L, 5 g/L, and 10 g/L) of creatine monohydrate for 8 weeks. We demonstrate that mitochondrial markers respond in a sex and depot specific manner. In iWAT, female rats displayed significant increases in COXIV, PDH-E1alpha, and cytochrome C protein content. Male rats exhibited gWAT specific increases in COXIV and PDH-E1alpha protein content. This study supports creatine supplementation as a potential method of UCP1-independant thermogenesis and highlights the importance of taking a sex-specific approach when examining the efficacy of browning therapeutics in future research.


Assuntos
Tecido Adiposo Branco/efeitos dos fármacos , Regulação da Temperatura Corporal/efeitos dos fármacos , Creatina/farmacologia , Suplementos Nutricionais , Mitocôndrias/efeitos dos fármacos , Tecido Adiposo Marrom/efeitos dos fármacos , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/metabolismo , Animais , Citocromos c/metabolismo , Relação Dose-Resposta a Droga , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Feminino , Masculino , Mitocôndrias/metabolismo , Piruvato Desidrogenase (Lipoamida) , Ratos Sprague-Dawley , Fatores Sexuais , Proteína Desacopladora 1/metabolismo
13.
Nutrients ; 13(8)2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34445003

RESUMO

Creatine has been considered an effective ergogenic aid for several decades; it can help athletes engaged in a variety of sports and obtain performance gains. Creatine supplementation increases muscle creatine stores; several factors have been identified that may modify the intramuscular increase and subsequent performance benefits, including baseline muscle Cr content, type II muscle fibre content and size, habitual dietary intake of Cr, aging, and exercise. Timing of creatine supplementation in relation to exercise has recently been proposed as an important consideration to optimise muscle loading and performance gains, although current consensus is lacking regarding the ideal ingestion time. Research has shifted towards comparing creatine supplementation strategies pre-, during-, or post-exercise. Emerging evidence suggests greater benefits when creatine is consumed after exercise compared to pre-exercise, although methodological limitations currently preclude solid conclusions. Furthermore, physiological and mechanistic data are lacking, in regard to claims that the timing of creatine supplementation around exercise moderates gains in muscle creatine and exercise performance. This review discusses novel scientific evidence on the timing of creatine intake, the possible mechanisms that may be involved, and whether the timing of creatine supplementation around exercise is truly a real concern.


Assuntos
Creatina/administração & dosagem , Suplementos Nutricionais , Exercício Físico/fisiologia , Músculo Esquelético/efeitos dos fármacos , Substâncias para Melhoria do Desempenho/administração & dosagem , Creatina/efeitos adversos , Creatina/metabolismo , Suplementos Nutricionais/efeitos adversos , Esquema de Medicação , Feminino , Humanos , Masculino , Músculo Esquelético/metabolismo , Substâncias para Melhoria do Desempenho/efeitos adversos , Substâncias para Melhoria do Desempenho/metabolismo , Fatores de Tempo , Resultado do Tratamento
14.
Molecules ; 26(15)2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34361796

RESUMO

Meat is a rich source of energy that provides high-value animal protein, fats, vitamins, minerals and trace amounts of carbohydrates. Globally, different types of meats are consumed to fulfill nutritional requirements. However, the increasing burden on the livestock industry has triggered the mixing of high-price meat species with low-quality/-price meat. This work aimed to differentiate different meat samples on the basis of metabolites. The metabolic difference between various meat samples was investigated through Nuclear Magnetic Resonance spectroscopy coupled with multivariate data analysis approaches like principal component analysis (PCA) and orthogonal partial least square-discriminant analysis (OPLS-DA). In total, 37 metabolites were identified in the gluteal muscle tissues of cow, goat, donkey and chicken using 1H-NMR spectroscopy. PCA was found unable to completely differentiate between meat types, whereas OPLS-DA showed an apparent separation and successfully differentiated samples from all four types of meat. Lactate, creatine, choline, acetate, leucine, isoleucine, valine, formate, carnitine, glutamate, 3-hydroxybutyrate and α-mannose were found as the major discriminating metabolites between white (chicken) and red meat (chevon, beef and donkey). However, inosine, lactate, uracil, carnosine, format, pyruvate, carnitine, creatine and acetate were found responsible for differentiating chevon, beef and donkey meat. The relative quantification of differentiating metabolites was performed using one-way ANOVA and Tukey test. Our results showed that NMR-based metabolomics is a powerful tool for the identification of novel signatures (potential biomarkers) to characterize meats from different sources and could potentially be used for quality control purposes in order to differentiate different meat types.


Assuntos
Contaminação de Alimentos/análise , Carne/análise , Metaboloma , Metabolômica/métodos , Aminoácidos/análise , Animais , Bovinos , Galinhas , Colina/análise , Creatina/análise , Equidae , Contaminação de Alimentos/prevenção & controle , Cabras , Humanos , Ácido Láctico/análise , Análise dos Mínimos Quadrados , Espectroscopia de Ressonância Magnética , Manose/análise , Análise Multivariada , Análise de Componente Principal , Especificidade da Espécie
15.
Nutrients ; 13(8)2021 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-34444689

RESUMO

Creatine is classified as a "sports supplement", but it also has health benefits. The purpose of this study was to assess use of creatine as a dietary supplement in adult non-athletes. Three hundred ninety-nine adults (19-89 years) completed an online survey. Among the respondents, 77% (n = 307) were regularly active, including participation in weightlifting (34%), running (34%), and cycling (21%). Twenty-eight percent (n = 111) reported use of creatine with an average dose of 6.4 ± 4.5 g. Daily creatine use was reported by 45%, and 38% reported using creatine 2-6 times weekly. Primary sources of information about creatine were trainers/coaches (29%), friends/family (32%), and internet (28%). Forty percent (n = 44) of creatine users were female. When compared by age, 46% of young, 32% of midlife, and 6% of old respondents reported creatine use with no differences in dose or frequency. Young and midlife respondents reported primarily trainers/coaches, friends/family, and internet as sources of information about creatine, but old respondents limited their sources to friends/family and fitness magazines. Although creatine is widely used by adult non-athletes who regularly exercise, dietitians and other healthcare providers are not the primary source of information. Fitness trainers can appropriately provide guidance and education regarding safe and effective use of creatine.


Assuntos
Creatina/uso terapêutico , Suplementos Nutricionais/estatística & dados numéricos , Exercício Físico/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esportes/psicologia , Inquéritos e Questionários , Adulto Jovem
16.
Nutrients ; 13(8)2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34444681

RESUMO

Creatine (Cr) and phosphocreatine (PCr) are physiologically essential molecules for life, given they serve as rapid and localized support of energy- and mechanical-dependent processes. This evolutionary advantage is based on the action of creatine kinase (CK) isozymes that connect places of ATP synthesis with sites of ATP consumption (the CK/PCr system). Supplementation with creatine monohydrate (CrM) can enhance this system, resulting in well-known ergogenic effects and potential health or therapeutic benefits. In spite of our vast knowledge about these molecules, no integrative analysis of molecular mechanisms under a systems biology approach has been performed to date; thus, we aimed to perform for the first time a convergent functional genomics analysis to identify biological regulators mediating the effects of Cr supplementation in health and disease. A total of 35 differentially expressed genes were analyzed. We identified top-ranked pathways and biological processes mediating the effects of Cr supplementation. The impact of CrM on miRNAs merits more research. We also cautiously suggest two dose-response functional pathways (kinase- and ubiquitin-driven) for the regulation of the Cr uptake. Our functional enrichment analysis, the knowledge-based pathway reconstruction, and the identification of hub nodes provide meaningful information for future studies. This work contributes to a better understanding of the well-reported benefits of Cr in sports and its potential in health and disease conditions, although further clinical research is needed to validate the proposed mechanisms.


Assuntos
Creatina/administração & dosagem , Perfilação da Expressão Gênica , Genômica/métodos , Desempenho Físico Funcional , Animais , Creatina/metabolismo , Creatina Quinase/metabolismo , Suplementos Nutricionais , Metabolismo Energético , Estudo de Associação Genômica Ampla , Humanos , Camundongos , Proteínas Quinases Ativadas por Mitógeno , Proteínas de Transporte de Neurotransmissores , Fosfocreatina/metabolismo , Transdução de Sinais
17.
Nutrients ; 13(8)2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34444869

RESUMO

There is great need for the identification of new, potentially modifiable risk factors for the poor health-related quality of life (HRQoL) and of the excess risk of mortality in dialysis-dependent chronic kidney disease patients. Creatine is an essential contributor to cellular energy homeostasis, yet, on a daily basis, 1.6-1.7% of the total creatine pool is non-enzymatically degraded to creatinine and subsequently lost via urinary excretion, thereby necessitating a continuous supply of new creatine in order to remain in steady-state. Because of an insufficient ability to synthesize creatine, unopposed losses to the dialysis fluid, and insufficient intake due to dietary recommendations that are increasingly steered towards more plant-based diets, hemodialysis patients are prone to creatine deficiency, and may benefit from creatine supplementation. To avoid problems with compliance and fluid balance, and, furthermore, to prevent intradialytic losses of creatine to the dialysate, we aim to investigate the potential of intradialytic creatine supplementation in improving outcomes. Given the known physiological effects of creatine, intradialytic creatine supplementation may help to maintain creatine homeostasis among dialysis-dependent chronic kidney disease patients, and consequently improve muscle status, nutritional status, neurocognitive status, HRQoL. Additionally, we describe the rationale and design for a block-randomized, double-blind, placebo-controlled pilot study. The aim of the pilot study is to explore the creatine uptake in the circulation and tissues following different creatine supplementation dosages.


Assuntos
Creatina/administração & dosagem , Suplementos Nutricionais , Diálise Renal , Insuficiência Renal Crônica/tratamento farmacológico , Método Duplo-Cego , Nível de Saúde , Humanos , Países Baixos , Projetos Piloto , Ensaios Clínicos Controlados Aleatórios como Assunto , Diálise Renal/efeitos adversos , Insuficiência Renal Crônica/sangue , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/fisiopatologia , Fatores de Tempo , Resultado do Tratamento
18.
Nutrients ; 13(7)2021 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-34371813

RESUMO

Creatine monohydrate (CrM) supplementation has been shown to improve body composition and muscle strength when combined with resistance training (RT); however, no study has evaluated the combination of this nutritional strategy with cluster-set resistance training (CS-RT). The purpose of this pilot study was to evaluate the effects of CrM supplementation during a high-protein diet and a CS-RT program on lower-limb fat-free mass (LL-FFM) and muscular strength. Twenty-three resistance-trained men (>2 years of training experience, 26.6 ± 8.1 years, 176.3 ± 6.8 cm, 75.6 ± 8.9 kg) participated in this study. Subjects were randomly allocated to a CS-RT+CrM (n = 8), a CS-RT (n = 8), or a control group (n = 7). The CS-RT+CrM group followed a CrM supplementation protocol with 0.1 g·kg-1·day-1 over eight weeks. Two sessions per week of lower-limb CS-RT were performed. LL-FFM corrected for fat-free adipose tissue (dual-energy X-ray absorptiometry) and muscle strength (back squat 1 repetition maximum (SQ-1RM) and countermovement jump (CMJ)) were measured pre- and post-intervention. Significant improvements were found in whole-body fat mass, fat percentage, LL-fat mass, LL-FFM, and SQ-1RM in the CS-RT+CrM and CS-RT groups; however, larger effect sizes were obtained in the CS-RT+CrM group regarding whole body FFM (0.64 versus 0.16), lower-limb FFM (0.62 versus 0.18), and SQ-1RM (1.23 versus 0.75) when compared to the CS-RT group. CMJ showed a significant improvement in the CS-RT+CrM group with no significant changes in CS-RT or control groups. No significant differences were found between groups. Eight weeks of CrM supplementation plus a high-protein diet during a CS-RT program has a higher clinical meaningfulness on lower-limb body composition and strength-related variables in trained males than CS-RT alone. Further research might study the potential health and therapeutic effects of this nutrition and exercise strategy.


Assuntos
Composição Corporal/efeitos dos fármacos , Creatina/farmacologia , Força Muscular/efeitos dos fármacos , Substâncias para Melhoria do Desempenho/farmacologia , Treinamento de Força/métodos , Absorciometria de Fóton , Tecido Adiposo/diagnóstico por imagem , Adulto , Dieta Rica em Proteínas , Suplementos Nutricionais , Exercício Físico/fisiologia , Humanos , Extremidade Inferior/fisiologia , Masculino , Músculo Esquelético/efeitos dos fármacos , Projetos Piloto , Adulto Jovem
19.
Nutrients ; 13(8)2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34444918

RESUMO

Mild cognitive impairment (MCI) designates the boundary area between cognitive function in natural aging and dementia, and this is viewed as a therapeutic window to prevent the occurrence of dementia. The current study investigated the neurocognitive effects of oral creatine (Cr) supplementation in young female Wistar rats that received intracerebroventricular injections of lipopolysaccharide (LPS) to mimic MCI. Neuromolecular changes within the dentate gyrus were analyzed following behavioral testing. We also investigated both neurocognitive and neuromolecular changes following Cr supplementation in the absence of LPS in young female Wistar rats to further investigate mechanisms. Interestingly, based on trial 2 of Barnes maze test, Cr supplementation ameliorated spatial learning and memory deficit induced by LPS, shown by decreased latency time and errors to reach the escape box (p < 0.0001, n = 12). Cr supplementation also attenuated recognition memory deficit induced by LPS, shown by increased amount of time taken to explore the new object (p = 0.002, n = 12) during novel object recognition testing. Within the dentate gyrus, Cr supplementation in LPS injected rats upregulated mTORC1 signaling (p = 0.026 for mTOR phosphorylation, p = 0.002 for p70S6K phosphorylation, n = 8) as well as the synapsin (p = 0.008) and PSD-95 synaptic proteins (p = 0.015), in comparisons to LPS injected rats. However, Cr supplementation failed to further enhance spatial memory and recognition memory in the absence of LPS. In conclusion, Cr ameliorates LPS-induced cognitive impairment in a rodent MCI model. Mechanistically, these phenotypic effects may, in part, be mitigated via an upregulation of mTORC1 signaling, and an enhancement in synaptogenesis in the dentate gyrus. While preliminary, these findings may inform future research investigating neurocognitive effects of Cr for MCI patients.


Assuntos
Disfunção Cognitiva/tratamento farmacológico , Creatina/administração & dosagem , Giro Denteado/metabolismo , Suplementos Nutricionais , Transtornos da Memória/tratamento farmacológico , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos , Animais , Comportamento Animal/efeitos dos fármacos , Disfunção Cognitiva/induzido quimicamente , Modelos Animais de Doenças , Feminino , Lipopolissacarídeos , Aprendizagem em Labirinto , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Transtornos da Memória/induzido quimicamente , Plasticidade Neuronal/efeitos dos fármacos , Ratos , Ratos Wistar , Reconhecimento Psicológico/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Memória Espacial/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos
20.
Int J Mol Sci ; 22(15)2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34360959

RESUMO

BACKGROUND: Rates of major depressive disorder (MDD) increase with living at altitude. In our model, rats housed at moderate altitude (in hypobaric hypoxia) exhibit increased depression-like behavior, altered brain serotonin and a lack of antidepressant response to most selective serotonin reuptake inhibitors (SSRIs). A forebrain deficit in the bioenergetic marker creatine is noted in people living at altitude or with MDD. METHODS: Rats housed at 4500 ft were given dietary creatine monohydrate (CRMH, 4% w/w, 5 weeks) vs. un-supplemented diet, and impact on depression-like behavior, brain bioenergetics, serotonin and SSRI efficacy assessed. RESULTS: CRMH significantly improved brain creatine in a sex-based manner. At altitude, CRMH increased serotonin levels in the female prefrontal cortex and striatum but reduced male striatal and hippocampal serotonin. Dietary CRMH was antidepressant in the forced swim test and anti-anhedonic in the sucrose preference test in only females at altitude, with motor behavior unchanged. CRMH improved fluoxetine efficacy (20 mg/kg) in only males at altitude: CRMH + SSRI significantly improved male striatal creatine and serotonin vs. CRMH alone. CONCLUSIONS: Dietary CRMH exhibits sex-based efficacy in resolving altitude-related deficits in brain biomarkers, depression-like behavior and SSRI efficacy, and may be effective clinically for SSRI-resistant depression at altitude. This is the first study to link CRMH treatment to improving brain serotonin.


Assuntos
Encéfalo/efeitos dos fármacos , Creatina/uso terapêutico , Transtorno Depressivo Maior/tratamento farmacológico , Fluoxetina/uso terapêutico , Inibidores de Captação de Serotonina/uso terapêutico , Serotonina/metabolismo , Animais , Encéfalo/metabolismo , Creatina/administração & dosagem , Creatina/farmacologia , Suplementos Nutricionais , Sinergismo Farmacológico , Metabolismo Energético , Feminino , Fluoxetina/administração & dosagem , Fluoxetina/farmacologia , Masculino , Ratos , Ratos Sprague-Dawley , Inibidores de Captação de Serotonina/administração & dosagem , Inibidores de Captação de Serotonina/farmacologia , Fatores Sexuais
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