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1.
Eur J Nutr ; 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39237620

RESUMO

PURPOSE: L-Ascorbic acid (vitamin C) is an essential water-soluble vitamin that plays an important role in various physiological functions, including immune health. The stability of vitamin C in the gastrointestinal tract its bioavailability is limited. This study aimed to investigate if a liposomal form of vitamin C can increase absorption compared to standard vitamin C. METHODS: In a randomized, double-blind, placebo-controlled, crossover fashion, 19 males and 8 females (n = 27; 36.0 ± 5.1 years, 165.0 ± 6.9 cm, 70.6 ± 7.1 kg) ingested a single-dose of placebo (PLA), 500 mg vitamin C (VIT C), and 500 mg liposomal vitamin C (LV-VIT C, LipoVantage®, Specnova, LLC, Tyson Corner, VA, USA). Venous blood samples were collected 0, 0.5-, 1-, 1.5-, 2-, 3-, 4-, 6-, 8-, 12-, and 24-hours after ingestion and were analyzed for plasma and leukocyte vitamin C concentration. RESULTS: VIT C and LV-VIT C demonstrated significantly greater Cmax and AUC0 - 24 in plasma and in leukocytes compared to placebo (p < 0.001). Additionally, LV-VIT C had significantly higher Cmax (plasma + 27%, leukocytes + 20%, p < 0.001) and AUC0 - 24 (plasma + 21%, leukocytes + 8%, p < 0.001) values as compared to VIT C. CONCLUSION: Liposomal formulation of vitamin C increases absorption into plasma and leukocytes. TRIAL REGISTRATION: Clinical Trials Registry - India (CTRI/2023/04/051789).

2.
Amino Acids ; 55(2): 253-261, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36474017

RESUMO

The activation of the mechanistic target of rapamycin complex 1 (mTORC1), a master regulator of protein synthesis, by anabolic stimuli (such as muscle contraction or essential amino acids) involves its translocation to the cell periphery. Leucine is generally considered the most anabolic of amino acids for its ability to independently modulate muscle protein synthesis. However, it is currently unknown if free leucine impacts region-specific mTORC1-mediated phosphorylation events and protein-protein interactions. In this clinical trial (NCT03952884; registered May 16, 2019), we used immunofluorescence methods to investigate the role of dietary leucine on the postprandial regulation of mTORC1 and ribosomal protein S6 (RPS6), an important downstream readout of mTORC1 activity. Eight young, healthy, recreationally active males (n = 8; 23 ± 3 yrs) ingested 2 g of leucine with vastus lateralis biopsies collected at baseline, 30, 60, and 180 min postprandial. Leucine promoted mTOR translocation to the periphery (~ 18-29%; p ≤ 0.012) and enhanced mTOR localization with the lysosome (~ 16%; both p = 0.049) at 30 and 60 min post-feeding. p-RPS6Ser240/244 staining intensity, a readout of mTORC1 activity, was significantly elevated at all postprandial timepoints in both the total fiber (~ 14-30%; p ≤ 0.032) and peripheral regions (~ 16-33%; p ≤ 0.014). Additionally, total and peripheral p-RPS6Ser240/244 staining intensity at 60 min was positively correlated (r = 0.74, p = 0.036; r = 0.80, p = 0.016, respectively) with rates of myofibrillar protein synthesis over 180 min. The ability of leucine to activate mTORC1 in peripheral regions favors an enhanced rate of MPS, as this is the intracellular space thought to be replete with the cellular machinery that facilitates this anabolic process.


Assuntos
Músculo Esquelético , Serina-Treonina Quinases TOR , Masculino , Humanos , Leucina/metabolismo , Fosforilação , Proteína S6 Ribossômica/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Músculo Esquelético/metabolismo , Ingestão de Alimentos
3.
Int J Sport Nutr Exerc Metab ; 33(2): 84-92, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36623508

RESUMO

Carnosine (ß-alanyl-L-histidine) and its methylated analogues anserine and balenine are highly concentrated endogenous dipeptides in mammalian skeletal muscle that are implicated in exercise performance. Balenine has a much better bioavailability and stability in human circulation upon acute ingestion, compared to carnosine and anserine. Therefore, ergogenic effects observed with acute carnosine and anserine supplementation may be even more pronounced with balenine. This study investigated whether acute balenine supplementation improves physical performance in four maximal and submaximal exercise modalities. A total of 20 healthy, active volunteers (14 males; six females) performed cycling sprints, maximal isometric contractions, a 4-km TT and 20-km TT following either preexercise placebo or 10 mg/kg of balenine ingestion. Physical, as well as mental performance, along with acid-base balance and glucose concentration were assessed. Balenine was unable to augment peak power (p = .3553), peak torque (p = .3169), time to complete the 4 km (p = .8566), nor 20 km time trial (p = .2660). None of the performances were correlated with plasma balenine or CN1 enzyme activity. In addition, no effect on pH, bicarbonate, and lactate was observed. Also, the supplement did not affect mental performance. In contrast, glucose remained higher during and after the 20 km time trial following balenine ingestion. In conclusion, these results overall indicate that the functionality of balenine does not fully resemble that of carnosine and anserine, since it was unable to elicit performance improvements with similar and even higher plasma concentrations.


Assuntos
Carnosina , Masculino , Animais , Feminino , Humanos , Carnosina/farmacologia , Anserina , Dipeptídeos , Suplementos Nutricionais , Mamíferos
4.
Regul Toxicol Pharmacol ; 116: 104760, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32771599

RESUMO

Adenosine-5'-triphosphate (ATP) is the primary source of energy for cells and oral supplementation with ATP offers numerous different health benefits, including the regulation of blood flow and muscle contraction. In this study, ATP, disodium salt, was administered by gavage to rats for 90 consecutive days at doses of 0 (control), 500, 1000, and 2000 mg kg BW-1·d-1 (n = 10 per sex/group). Subchronic administration of ATP was well tolerated at all dose levels. Body weights and feed consumption body weight gains were similar between ATP-treated and control rats. Minor differences were seen in hematology and blood chemistry; however, these changes were not dose related and therefore not of biological or toxicological significance. Only one difference was observed in absolute organ weights, females of the high dose had increased kidney and increased relative kidney and liver weights; however, these differences were not seen in males nor appeared to be dose related. No biological or toxicological significant differences were observed in thyroid function or urine analysis. The incidence of histopathological lesions was low and similar between treated and control groups. Based upon these findings, the no-observed-adverse-effect level (NOAEL) was determined to be ≥ 2000 mg kg BW-1·d-1, which was the highest dose tested.


Assuntos
Trifosfato de Adenosina/toxicidade , Administração Oral , Animais , Feminino , Masculino , Nível de Efeito Adverso não Observado , Ratos Sprague-Dawley , Testes de Toxicidade Subcrônica
5.
Eur J Nutr ; 57(3): 929-938, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28204880

RESUMO

PURPOSE: The optimal health benefits of curcumin are limited by its low solubility in water and corresponding poor intestinal absorption. Cyclodextrins (CD) can form inclusion complexes on a molecular basis with lipophilic compounds, thereby improving aqueous solubility, dispersibility, and absorption. In this study, we investigated the bioavailability of a new γ-cyclodextrin curcumin formulation (CW8). This formulation was compared to a standardized unformulated curcumin extract (StdC) and two commercially available formulations with purported increased bioavailability: a curcumin phytosome formulation (CSL) and a formulation of curcumin with essential oils of turmeric extracted from the rhizome (CEO). METHODS: Twelve healthy human volunteers participated in a double-blinded, cross-over study. The plasma concentrations of the individual curcuminoids that are present in turmeric (namely curcumin, demethoxycurcumin, and bisdemethoxycurcumin) were determined at baseline and at various intervals after oral administration over a 12-h period. RESULTS: CW8 showed the highest plasma concentrations of curcumin, demethoxycurcumin, and total curcuminoids, whereas CSL administration resulted in the highest levels of bisdemethoxycurcumin. CW8 (39-fold) showed significantly increased relative bioavailability of total curcuminoids (AUC0-12) in comparison with the unformulated StdC. CONCLUSION: The data presented suggest that γ-cyclodextrin curcumin formulation (CW8) significantly improves the absorption of curcuminoids in healthy humans.


Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Antioxidantes/administração & dosagem , Curcumina/administração & dosagem , Suplementos Nutricionais , Aditivos Alimentares/química , Absorção Intestinal , gama-Ciclodextrinas/química , Adulto , Antineoplásicos Fitogênicos/sangue , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/metabolismo , Antioxidantes/análise , Antioxidantes/química , Antioxidantes/metabolismo , Área Sob a Curva , Estudos de Coortes , Estudos Cross-Over , Curcumina/análogos & derivados , Curcumina/análise , Curcumina/química , Curcumina/metabolismo , Diarileptanoides , Método Duplo-Cego , Feminino , Manipulação de Alimentos , Humanos , Masculino , Valor Nutritivo , Adulto Jovem
6.
J Am Coll Nutr ; 36(3): 177-183, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28080323

RESUMO

OBJECTIVE: Oral adenosine-5'-triphosphate (ATP) administration has failed to increase plasma ATP levels; however, chronic supplementation with ATP has shown to increase power, strength, lean body mass, and blood flow in trained athletes. The purpose of this study was to investigate the effects of ATP supplementation on postexercise ATP levels and on muscle activation and excitability and power following a repeated sprint bout. METHODS: In a double-blind, placebo-controlled, randomized design, 42 healthy male individuals were given either 400 mg of ATP as disodium salt or placebo for 2 weeks prior to an exercise bout. During the exercise bout, muscle activation and excitability (ME, ratio of power output to muscle activation) and Wingate test peak power were measured during all sprints. ATP and metabolites were measured at baseline, after supplementation, and immediately following exercise. RESULTS: Oral ATP supplementation prevented a drop in ATP, adenosine-5'-diphosphate (ADP), and adenosine-5'-monophosphate (AMP) levels postexercise (p < 0.05). No group by time interaction was observed for muscle activation. Following the supplementation period, muscle excitability significantly decreased in later bouts 8, 9, and 10 in the placebo group (-30.5, -28.3, and -27.9%, respectively; p < 0.02), whereas ATP supplementation prevented the decline in later bouts. ATP significantly increased Wingate peak power in later bouts compared to baseline (bout 8: +18.3%, bout 10: +16.3%). CONCLUSIONS: Oral ATP administration prevents exercise-induced declines in ATP and its metabolite and enhances peak power and muscular excitability, which may be beneficial for sports requiring repeated high-intensity sprinting bouts.


Assuntos
Trifosfato de Adenosina/farmacologia , Desempenho Atlético , Exercício Físico , Músculo Esquelético/efeitos dos fármacos , Trifosfato de Adenosina/administração & dosagem , Administração Oral , Adolescente , Método Duplo-Cego , Humanos , Masculino , Músculo Esquelético/fisiologia , Adulto Jovem
7.
Appetite ; 113: 264-273, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28235621

RESUMO

We examined if 12 weeks of capsaicinoid (CAP) supplementation affected appetite, body composition and metabolic health markers. Seventy seven healthy male and female volunteers (30 ± 1 y, 171.2 ± 9.8 cm, 81.0 ± 2.2 kg, 27.5 ± 0.6 kg/m2) were randomly assigned to ingest either low-dose CAP (2 mg/d; L-CAP, n = 27), high-dose CAP (4 mg/d; H-CAP, n = 22) from Capsimax or placebo (corn starch; PLA, n = 28) for 12 weeks. At baseline (0 WK), 6 weeks (6 WK) and 12 weeks (12 WK) waist: hip ratio, body composition via dual energy x-ray absorptiometry (DEXA, 0 WK and 12 WK only), self-reported Calorie intakes, appetite levels via Council on Nutrition Appetite Questionnaire (CNAQ) and serum metabolic health markers (0 WK and 12 WK only) were analyzed. Moreover, an oral glucose tolerance test (OGTT) was administered at 0 WK and 12 WK, and serum glucose and insulin responses were examined 30-120 min post test-drink consumption. Waist: hip ratio significantly decreased in L-CAP from 0 WK to 6 WK (p < 0.05), although supplementation did not significantly affect body composition. H-CAP consumed less kcal/d compared to PLA at 12 WK (difference = 257 kcal/d, p < 0.05) and L-CAP participants at 12 WK (difference = 247, p < 0.05). Twenty-three percent (9/39) of the originally-enrolled H-CAP participants reported GI distress, although no participants in the L-CAP group reported such adverse events. Interestingly, H-CAP participants presented significant increases in serum insulin as well as significant decreases in serum HDL cholesterol levels from WK0 to WK12. However, supplementation did not affect the insulin response to the administered OGTT and/or other indices of insulin sensitivity. These data suggest that H-CAP supplementation reduces self-reported energy intake after 12 weeks of supplementation, and L-CAP supplementation also reduces waist: hip ratio. Longer-term effects of capsaicinoid supplementation on basal insulin and cholesterol levels warrant further investigation.


Assuntos
Apetite/efeitos dos fármacos , Composição Corporal/efeitos dos fármacos , Capsaicina/farmacologia , Suplementos Nutricionais , Sobrepeso/terapia , Adulto , Glicemia/análise , Colesterol/sangue , Ingestão de Energia/efeitos dos fármacos , Feminino , Teste de Tolerância a Glucose , Voluntários Saudáveis , Humanos , Insulina/sangue , Resistência à Insulina/fisiologia , Masculino , Sobrepeso/sangue , Relação Cintura-Quadril
8.
J Strength Cond Res ; 30(7): 1843-54, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24714541

RESUMO

Lowery, RP, Joy, JM, Rathmacher, JA, Baier, SM, Fuller, JC Jr, Shelley, MC II, Jäger, R, Purpura, M, Wilson, SMC, and Wilson, JM. Interaction of beta-hydroxy-beta-methylbutyrate free acid and adenosine triphosphate on muscle mass, strength, and power in resistance trained individuals. J Strength Cond Res 30(7): 1843-1854, 2016-Adenosine-5'-triphosphate (ATP) supplementation helps maintain performance under high fatiguing contractions and with greater fatigue recovery demands also increase. Current evidence suggests that the free acid form of ß-hydroxy-ß-methylbutyrate (HMB-FA) acts by speeding regenerative capacity of skeletal muscle after high-intensity or prolonged exercise. Therefore, we investigated the effects of 12 weeks of HMB-FA (3 g) and ATP (400 mg) administration on lean body mass (LBM), strength, and power in trained individuals. A 3-phase double-blind, placebo-, and diet-controlled study was conducted. Phases consisted of an 8-week periodized resistance training program (phase 1), followed by a 2-week overreaching cycle (phase 2), and a 2-week taper (phase 3). Lean body mass was increased by a combination of HMB-FA/ATP by 12.7% (p < 0.001). In a similar fashion, strength gains after training were increased in HMB-FA/ATP-supplemented subjects by 23.5% (p < 0.001). Vertical jump and Wingate power were increased in the HMB-FA/ATP-supplemented group compared with the placebo-supplemented group, and the 12-week increases were 21.5 and 23.7%, respectively. During the overreaching cycle, strength and power declined in the placebo group (4.3-5.7%), whereas supplementation with HMB-FA/ATP resulted in continued strength gains (1.3%). In conclusion, HMB-FA and ATP in combination with resistance exercise training enhanced LBM, power, and strength. In addition, HMB-FA plus ATP blunted the typical response to overreaching, resulting in a further increase in strength during that period. It seems that the combination of HMB-FA/ATP could benefit those who continuously train at high levels such as elite athletes or military personnel.


Assuntos
Trifosfato de Adenosina/farmacologia , Composição Corporal/efeitos dos fármacos , Força Muscular/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Valeratos/farmacologia , Adulto , Suplementos Nutricionais , Método Duplo-Cego , Interações Medicamentosas , Teste de Esforço , Humanos , Masculino , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/fisiologia , Treinamento Resistido , Ultrassonografia , Adulto Jovem
9.
Nutr J ; 13: 11, 2014 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-24461029

RESUMO

BACKGROUND: The potential health benefits of curcumin are limited by its poor solubility, low absorption from the gut, rapid metabolism and rapid systemic elimination. The purpose of this study was the comparative measurement of the increases in levels of curcuminoids (curcumin, demethoxycurcumin, bisdemethoxycurcumin) and the metabolite tetrahydrocurcumin after oral administration of three different curcumin formulations in comparison to unformulated standard. METHODS: The relative absorption of a curcumin phytosome formulation (CP), a formulation with volatile oils of turmeric rhizome (CTR) and a formulation of curcumin with a combination of hydrophilic carrier, cellulosic derivatives and natural antioxidants (CHC) in comparison to a standardized curcumin mixture (CS) was investigated in a randomized, double-blind, crossover human study in healthy volunteers. Samples were analyzed by HPLC-MS/MS. RESULTS: Total curcuminoids appearance in the blood was 1.3-fold higher for CTR and 7.9-fold higher for CP in comparison to unformulated CS. CHC showed a 45.9-fold higher absorption over CS and significantly improved absorption over CP (5.8-fold) and CTR (34.9-fold, all p < 0.001). CONCLUSION: A formulation of curcumin with a combination of hydrophilic carrier, cellulosic derivatives and natural antioxidants significantly increases curcuminoid appearance in the blood in comparison to unformulated standard curcumin CS, CTR and CP.


Assuntos
Curcumina/análogos & derivados , Absorção Intestinal/fisiologia , Administração Oral , Adulto , Curcumina/administração & dosagem , Diarileptanoides , Feminino , Humanos , Masculino , Solubilidade
10.
Sci Rep ; 14(1): 12685, 2024 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-38830962

RESUMO

White kidney bean (Phaseolus vulgaris L.) extracts can aid weight management by reducing calorie intake from complex carbohydrates through alpha-amylase inhibition. We examined the impact of a proprietary aqueous extract from whole dried white kidney beans standardized by its alpha-amylase inhibitor activity (Phase 2 white kidney bean extract (WKBE)) on weight management in subjects with overweight and moderate obesity. In a randomized, double-blind, placebo-controlled fashion, 81 participants completed the study and ingested either a high dose of Phase 2 (1000 mg, WKBE HIGH), a low dose (700 mg, WKBE LOW), or a matching placebo (microcrystalline cellulose, PLA) three times a day, 30 min before meals, for 12 weeks during a calorie restricted diet. In a dose-dependent manner, Phase 2 significantly reduced body weight, fat mass, BMI, waist, hip and in the WKBE HIGH group thigh circumference. Phase 2 is an effective and safe supplement aiding weight and fat loss. ClinicalTrials.gov identifier NCT02930668.


Assuntos
Phaseolus , Extratos Vegetais , Humanos , Masculino , Feminino , Método Duplo-Cego , Phaseolus/química , Pessoa de Meia-Idade , Adulto , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Redução de Peso/efeitos dos fármacos , Obesidade/tratamento farmacológico , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/metabolismo , Sobrepeso/tratamento farmacológico , Lectinas de Plantas
11.
Nutrients ; 16(7)2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38613045

RESUMO

Biotransformation of minerals via glycosylation by microorganisms such as yeast and/or probiotics yields nutrients bound to a food matrix, resulting in increased bioavailability. The purpose of this study was to compare the effects of glycoprotein matrix-bound zinc (GPM) on absorption compared to inorganic zinc oxide. Sixteen participants ingested 11 mg of zinc as either GPM™ Soy-Free Zinc (GPM, Ashland, Kearny, NJ, USA) or zinc oxide (USP). Blood samples were taken at 0 (i.e., baseline), 30, 60, 90, 120, 180, 240, 300, 360, 420, and 480 min post-ingestion. GPM zinc concentrations were significantly higher at 120 min (p = 0.02; 12.4 ± 5.1 mcg/dL), 180 min (p = 0.002; 16.8 ± 5.1 mcg/dL), and 240 min (p = 0.007; 14.6 ± 5.1 mcg/dL) in comparison to USP zinc oxide. In addition, GPM zinc significantly increased iAUC by 40% (5840 ± 2684 vs. 4183 ± 1132 mcg/dL * 480 min, p = 0.02), and Cmax values were 10% higher in GPM compared to USP (148 ± 21 mcg/dL vs. 135 ± 17.5 mcg/dL, p = 0.08). Tmax was 12% slower in GPM compared to USP (112.5 ± 38.7 min vs. 127.5 ± 43.1 min); however, differences in Tmax failed to reach statistical significance (p = 0.28). Zinc bound to a glycoprotein matrix significantly increased absorption compared to zinc oxide.


Assuntos
Probióticos , Óxido de Zinco , Humanos , Zinco , Estudos Cross-Over , Glicoproteínas , Saccharomyces cerevisiae
12.
Nutrients ; 16(12)2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38931168

RESUMO

BACKGROUND: Ashwagandha has been reported to reduce stress and attenuate cognitive decline associated with inflammation and neurodegeneration in clinical populations. However, the effects as a potential nootropic nutrient in younger populations are unclear. This study examined the effects of liposomal ashwagandha supplementation on cognitive function, mood, and markers of health and safety in healthy young men and women. METHODS: 59 men and women (22.7 ± 7 yrs., 74.9 ± 16 kg, 26.2 ± 5 BMI) fasted for 12 h, donated a fasting blood sample, and were administered the COMPASS cognitive function test battery (Word Recall, Word recognition, Choice Reaction Time Task, Picture Recognition, Digit Vigilance Task, Corsi Block test, Stroop test) and profile of mood states (POMS). In a randomized and double-blind manner, participants were administered 225 mg of a placebo (Gum Arabic) or ashwagandha (Withania somnifera) root and leaf extract coated with a liposomal covering. After 60-min, participants repeated cognitive assessments. Participants continued supplementation (225 mg/d) for 30 days and then returned to the lab to repeat the experiment. Data were analyzed using a general linear model (GLM) univariate analysis with repeated measures and pairwise comparisons of mean changes from baseline with 95% confidence intervals (CI). RESULTS: Ashwagandha supplementation improved acute and/or 30-day measures of Word Recall (correct and recalled attempts), Choice Reaction Time (targets identified), Picture Recognition ("yes" correct responses, correct and overall reaction time), Digit Vigilance (correct reaction time), Stroop Color-Word (congruent words identified, reaction time), and POMS (tension and fatigue) from baseline more consistently with several differences observed between groups. CONCLUSION: Results support contentions that ashwagandha supplementation (225 mg) may improve some measures of memory, attention, vigilance, attention, and executive function while decreasing perceptions of tension and fatigue in younger healthy individuals. Retrospectively registered clinical trial ISRCTN58680760.


Assuntos
Afeto , Cognição , Suplementos Nutricionais , Extratos Vegetais , Humanos , Masculino , Feminino , Cognição/efeitos dos fármacos , Método Duplo-Cego , Adulto Jovem , Adulto , Afeto/efeitos dos fármacos , Extratos Vegetais/farmacologia , Adolescente , Tempo de Reação/efeitos dos fármacos , Biomarcadores/sangue , Lipossomos , Folhas de Planta/química , Raízes de Plantas/química
13.
J Diet Suppl ; 21(5): 608-632, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38745415

RESUMO

This study investigated if paraxanthine (PX) impacts energy expenditure, lipolysis and perceptual responses. In a randomized, double-blind, placebo-controlled, crossover fashion, 21 adults (13 M, 8 F; 26.0 ± 6.4 years, 174.9 ± 11.5 cm, 81.0 ± 15.7 kg body mass, 26.3 ± 3.4 kg/m2) consumed a placebo (PLA), 100 mg (PX100), 200 mg (PX200), and 300 mg of PX (PX300, enfinity®, Ingenious Ingredients, L.P. Lewisville, TX, USA). Venous blood was collected 0, 30, 60, 90, 120 and 180 min (min) after ingestion and analyzed for glycerol and free fatty acids. Resting hemodynamics, metabolic rate and perceptual indicators of hunger, appetite and anxiety were evaluated. Mixed factorial analysis of variance were used to evaluate changes time within and between groups. Heart rate decreased in PX100 compared to PLA 60 (p = .022) and 180 min (p = .001). Blood pressure did not change. Hunger ratings in PLA increased 30 (p = .05), 60 (p = .04), 90 (p = .02), and 180 min (p = .05) after ingestion when compared to PX200. PX200 increased energy expenditure (all p < .05) when compared to PLA. Rates of fat oxidation tended to increase 90 (p = .056) and 120 min (p = .066) in PX200 compared to PLA. Free fatty acids increased in PX300 compared to PLA (p = .002). Glycerol did not change. Ingestion of PX200 augmented energy expenditure and hunger ratings when compared to PLA without impacting hemodynamics or lipolysis.


Assuntos
Apetite , Estudos Cross-Over , Metabolismo Energético , Fome , Lipólise , Humanos , Lipólise/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Adulto , Feminino , Masculino , Método Duplo-Cego , Apetite/efeitos dos fármacos , Fome/efeitos dos fármacos , Adulto Jovem , Relação Dose-Resposta a Droga , Glicerol/sangue , Ácidos Graxos não Esterificados/sangue , Frequência Cardíaca/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Suplementos Nutricionais
14.
J Appl Physiol (1985) ; 136(6): 1388-1399, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38385186

RESUMO

Feeding and resistance exercise stimulate myofibrillar protein synthesis (MPS) rates in healthy adults. This anabolic characterization of "healthy adults" has been namely focused on males. Therefore, the purpose of this study was to examine the temporal responses of MPS and anabolic signaling to resistance exercise alone or combined with the ingestion of protein in postmenopausal females and compare postabsorptive rates with young females. Sixteen females [60 ± 7 yr; body mass index (BMI) = 26 ± 12 kg·m-2] completed an acute bout of unilateral resistance exercise before consuming either: a fortified whey protein supplement (WHEY) or water. Participants received primed continuous infusions of L-[ring-13C6]phenylalanine with bilateral muscle biopsies before and after treatment ingestion at 2 h and 4 h in nonexercised and exercised legs. Resistance exercise transiently increased MPS above baseline at 0-2 h in the water condition (P = 0.007). Feeding after resistance exercise resulted in a late phase (2-4 h) increase in MPS in the WHEY condition (P = 0.005). In both conditions, resistance exercise did not enhance the cumulative (0-4 h) MPS response. In the nonexercised leg, MPS did not differ at 0-2 h, 2-4 h, or 0-4 h of the measurement periods (all, P > 0.05). Likewise, there were no changes in the phosphorylation of p70S6K, AMPKα, or total and phosphorylated yes-associated protein on Ser127. Finally, postabsorptive MPS was lower in premenopausal versus postmenopausal females (P = 0.023). Our results demonstrate that resistance exercise-induced changes in MPS are temporally regulated, but do not result in greater cumulative (0-4 h) MPS in postmenopausal women.NEW & NOTEWORTHY An adequate quality and quantity of skeletal muscle is relevant to support physical performance and metabolic health. Muscle protein synthesis (MPS) is an established remodeling marker, which can be hypertrophic or nonhypertrophic. Importantly, protein ingestion and resistance exercise are two strategies that support healthy muscle by stimulating MPS. Our study shows postmenopause modulates baseline MPS that may diminish the MPS response to the fundamental anabolic stimuli of protein ingestion and resistance exercise in older females.


Assuntos
Proteínas Musculares , Miofibrilas , Pós-Menopausa , Período Pós-Prandial , Treinamento Resistido , Proteínas do Soro do Leite , Humanos , Feminino , Pós-Menopausa/fisiologia , Pós-Menopausa/metabolismo , Treinamento Resistido/métodos , Pessoa de Meia-Idade , Período Pós-Prandial/fisiologia , Miofibrilas/metabolismo , Proteínas Musculares/biossíntese , Proteínas Musculares/metabolismo , Proteínas do Soro do Leite/metabolismo , Músculo Esquelético/metabolismo , Descanso/fisiologia , Idoso , Fenilalanina/metabolismo , Biossíntese de Proteínas/fisiologia , Suplementos Nutricionais , Adulto , Exercício Físico/fisiologia , Fosforilação
15.
Nutrients ; 16(7)2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38613023

RESUMO

BACKGROUND: Microalgae like Phaeodactylum tricornutum (PT) contain the carotenoid, fucoxanthin, which has been purported to promote fat loss, lower blood lipids, and improve glucose management. This study examined whether dietary supplementation with microalgae extracts from PT containing 4.4 mg/d of fucoxanthin affects changes in body composition or health markers in overweight women during an exercise and diet intervention. MATERIALS AND METHODS: A total of 37 females (28.6 ± 7.9 years, 80.2 ± 14.9 kg, 29.6 ± 3.8 kg/m², 41.4 ± 4.2% fat) fasted for 12 h, donated a fasting blood sample, completed health and mood state inventories, and undertook body composition, health, and exercise assessments. In a counterbalanced, randomized, and double-blind manner, participants ingested a placebo (PL), or microalgae extract of Phaeodactylum tricornutum standardized to 4.4 mg of fucoxanthin (FX) for 12 weeks while participating in a supervised exercise program that included resistance-training and walking (3 days/week) with encouragement to accumulate 10,000 steps/day on remaining days of the week. The diet intervention involved reducing energy intake by about -300 kcal/d (i.e., ≈1400-1600 kcals/d, 55% carbohydrate, 30% fat, 15% protein) to promote a -500 kcal/d energy deficit with exercise. Follow-up testing was performed at 6 and 12 weeks. A general linear model (GLM) with repeated measures statistical analysis was used to analyze group responses and changes from baseline with 95% confidence intervals. RESULTS: Dietary supplementation with microalgae extract from PT containing fucoxanthin for 12 weeks did not promote additional weight loss or fat loss in overweight but otherwise healthy females initiating an exercise and diet intervention designed to promote modest weight loss. However, fucoxanthin supplementation preserved bone mass, increased bone density, and saw greater improvements in walking steps/day, resting heart rate, aerobic capacity, blood lipid profiles, adherence to diet goals, functional activity tolerance, and measures of quality of life. Consequently, there appears to be some benefit to supplementing microalgae extract from PT containing fucoxanthin during a diet and exercise program. Registered clinical trial #NCT04761406.


Assuntos
Microalgas , Xantofilas , Feminino , Humanos , Suplementos Nutricionais , Sobrepeso/terapia , Qualidade de Vida , Redução de Peso , Adulto Jovem , Adulto
16.
J Int Soc Sports Nutr ; 21(1): 2352779, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38725238

RESUMO

RATIONALE: Intense exercise promotes fatigue and can impair cognitive function, particularly toward the end of competition when decision-making is often critical for success. For this reason, athletes often ingest caffeinated energy drinks prior to or during exercise to help them maintain focus, reaction time, and cognitive function during competition. However, caffeine habituation and genetic sensitivity to caffeine (CA) limit efficacy. Paraxanthine (PX) is a metabolite of caffeine reported to possess nootropic properties. This study examined whether ingestion of PX with and without CA affects pre- or post-exercise cognitive function. METHODS: 12 trained runners were randomly assigned to consume in a double-blind, randomized, and crossover manner 400 mg of a placebo (PL); 200 mg of PL + 200 mg of CA; 200 mg of PL + 200 mg of PX (ENFINITY®, Ingenious Ingredients); or 200 mg PX + 200 mg of CA (PX+CA) with a 7-14-day washout between treatments. Participants donated fasting blood samples and completed pre-supplementation (PRE) side effects questionnaires, the Berg-Wisconsin Card Sorting Test (BCST), and the Psychomotor Vigilance Task Test (PVTT). Participants then ingested the assigned treatment and rested for 60 minutes, repeated tests (PRE-EX), performed a 10-km run on a treadmill at a competition pace, and then repeated tests (POST-EX). Data were analyzed using General Linear Model (GLM) univariate analyses with repeated measures and percent changes from baseline with 95% confidence intervals. RESULTS: BCST correct responses in the PX treatment increased from PRE-EX to POST-EX (6.8% [1.5, 12.1], p = 0.012). The error rate in the PL (23.5 [-2.8, 49.8] %, p = 0.078) and CA treatment (31.5 [5.2, 57.8] %, p = 0.02) increased from PRE-EX values with POST-EX errors tending to be lower with PX treatment compared to CA (-35.7 [-72.9, 1.4] %, p = 0.059). POST-EX perseverative errors with PAR rules were significantly lower with PX treatment than with CA (-26.9 [-50.5, -3.4] %, p = 0.026). Vigilance analysis revealed a significant interaction effect in Trial #2 mean reaction time values (p = 0.049, ηp2 = 0.134, moderate to large effect) with POST-EX reaction times tending to be faster with PX and CA treatment. POST-EX mean reaction time of all trials with PX treatment was significantly faster than PL (-23.2 [-43.4, -2.4] %, p = 0.029) and PX+CA (-29.6 [-50.3, -8.80] %, p = 0.006) treatments. There was no evidence that PX ingestion adversely affected ratings of side effects associated with stimulant intake or clinical blood markers. CONCLUSIONS: Results provide some evidence that pre-exercise PX ingestion improves prefrontal cortex function, attenuates attentional decline, mitigates cognitive fatigue, and improves reaction time and vigilance. Adding CA to PX did not provide additional benefits. Therefore, PX ingestion may serve as a nootropic alternative to CA.


Assuntos
Cafeína , Cognição , Estudos Cross-Over , Corrida , Humanos , Cafeína/administração & dosagem , Cafeína/farmacologia , Método Duplo-Cego , Cognição/efeitos dos fármacos , Corrida/fisiologia , Masculino , Adulto , Teofilina/farmacologia , Teofilina/administração & dosagem , Feminino , Tempo de Reação/efeitos dos fármacos , Adulto Jovem , Substâncias para Melhoria do Desempenho/administração & dosagem , Substâncias para Melhoria do Desempenho/farmacologia
17.
Nutr J ; 12: 86, 2013 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-23782948

RESUMO

Consumption of moderate amounts of animal-derived protein has been shown to differently influence skeletal muscle hypertrophy during resistance training when compared with nitrogenous and isoenergetic amounts of plant-based protein administered in small to moderate doses. Therefore, the purpose of the study was to determine if the post-exercise consumption of rice protein isolate could increase recovery and elicit adequate changes in body composition compared to equally dosed whey protein isolate if given in large, isocaloric doses.


Assuntos
Composição Corporal , Suplementos Nutricionais , Proteínas do Leite/administração & dosagem , Oryza/química , Proteínas de Plantas/administração & dosagem , Treinamento Resistido , Proteínas Alimentares/administração & dosagem , Método Duplo-Cego , Humanos , Masculino , Músculo Esquelético/metabolismo , Proteínas do Soro do Leite , Adulto Jovem
19.
Sci Rep ; 13(1): 6484, 2023 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-37081019

RESUMO

Balenine possesses some of carnosine's and anserine's functions, yet it appears more resistant to the hydrolysing CN1 enzyme. The aim of this study was to elucidate the stability of balenine in the systemic circulation and its bioavailability in humans following acute supplementation. Two experiments were conducted in which (in vitro) carnosine, anserine and balenine were added to plasma to compare degradation profiles and (in vivo) three increasing doses (1-4-10 mg/kg) of balenine were acutely administered to 6 human volunteers. Half-life of balenine (34.9 ± 14.6 min) was respectively 29.1 and 16.3 times longer than that of carnosine (1.20 ± 0.36 min, p = 0.0044) and anserine (2.14 ± 0.58 min, p = 0.0044). In vivo, 10 mg/kg of balenine elicited a peak plasma concentration (Cmax) of 28 µM, which was 4 and 18 times higher than with 4 (p = 0.0034) and 1 mg/kg (p = 0.0017), respectively. CN1 activity showed strong negative correlations with half-life (ρ = - 0.829; p = 0.0583), Cmax (r = - 0.938; p = 0.0372) and incremental area under the curve (r = - 0.825; p = 0.0433). Overall, balenine seems more resistant to CN1 hydrolysis resulting in better in vivo bioavailability, yet its degradation remains dependent on enzyme activity. Although a similar functionality as carnosine and anserine remains to be demonstrated, opportunities arise for balenine as nutraceutical or ergogenic aid.


Assuntos
Carnosina , Humanos , Carnosina/metabolismo , Anserina/metabolismo , Suplementos Nutricionais
20.
Nutrients ; 14(5)2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35268011

RESUMO

In 2011, we published a paper providing an overview about the bioavailability, efficacy, and regulatory status of creatine monohydrate (CrM), as well as other "novel forms" of creatine that were being marketed at the time. This paper concluded that no other purported form of creatine had been shown to be a more effective source of creatine than CrM, and that CrM was recognized by international regulatory authorities as safe for use in dietary supplements. Moreover, that most purported "forms" of creatine that were being marketed at the time were either less bioavailable, less effective, more expensive, and/or not sufficiently studied in terms of safety and/or efficacy. We also provided examples of several "forms" of creatine that were being marketed that were not bioavailable sources of creatine or less effective than CrM in comparative effectiveness trials. We had hoped that this paper would encourage supplement manufacturers to use CrM in dietary supplements given the overwhelming efficacy and safety profile. Alternatively, encourage them to conduct research to show their purported "form" of creatine was a bioavailable, effective, and safe source of creatine before making unsubstantiated claims of greater efficacy and/or safety than CrM. Unfortunately, unsupported misrepresentations about the effectiveness and safety of various "forms" of creatine have continued. The purpose of this critical review is to: (1) provide an overview of the physiochemical properties, bioavailability, and safety of CrM; (2) describe the data needed to substantiate claims that a "novel form" of creatine is a bioavailable, effective, and safe source of creatine; (3) examine whether other marketed sources of creatine are more effective sources of creatine than CrM; (4) provide an update about the regulatory status of CrM and other purported sources of creatine sold as dietary supplements; and (5) provide guidance regarding the type of research needed to validate that a purported "new form" of creatine is a bioavailable, effective and safe source of creatine for dietary supplements. Based on this analysis, we categorized forms of creatine that are being sold as dietary supplements as either having strong, some, or no evidence of bioavailability and safety. As will be seen, CrM continues to be the only source of creatine that has substantial evidence to support bioavailability, efficacy, and safety. Additionally, CrM is the source of creatine recommended explicitly by professional societies and organizations and approved for use in global markets as a dietary ingredient or food additive.


Assuntos
Creatina , Suplementos Nutricionais , Disponibilidade Biológica , Creatina/efeitos adversos , Suplementos Nutricionais/efeitos adversos , Aditivos Alimentares
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