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1.
Nutrients ; 15(4)2023 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-36839281

RESUMO

This study investigated 10 weeks of ß-alanine (BA) supplementation on changes in cognitive function, mood, and physical performance in 100 older adults (70.6 ± 8.7 y). Participants were randomized into a BA (2.4 g·d-1) or placebo (PL) group. Testing occurred prior to supplementation (PRE), at the midpoint (MID), and at week-10 (POST). Participants completed cognitive function assessments, including the Montreal cognitive assessment (MOCA) and the Stroop pattern recognition test, at each testing session. Behavioral questionnaires [i.e., the profile of mood states, geriatric depression scale (GDS), and geriatric anxiety scale (GAS)] and physical function assessments (grip strength and timed sit-to-stand) were also conducted. No difference between groups was noted in MoCA scores (p = 0.19). However, when examining participants whose MOCA scores at PRE were at or below normal (i.e., ≤26), participants in BA experienced significant improvements in MOCA scores at MID (13.6%, p = 0.009) and POST (11.8%, p = 0.016), compared to PL. No differences were noted in mood scores, GAS, or any of the physical performance measures. A significant decrease was observed in the GDS for participants consuming BA but not in PL. Results suggested that BA supplementation can improve cognitive function in older adults whose cognitive function at baseline was at or below normal and possibly reduce depression scores.


Assuntos
Cognição , Suplementos Nutricionais , Humanos , Idoso , Afeto , Força da Mão , beta-Alanina , Método Duplo-Cego
2.
Nutrients ; 15(4)2023 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-36839397

RESUMO

ß-alanine is a nonessential amino acid that combines with the amino acid histidine to form the intracellular dipeptide carnosine, an important intracellular buffer. Evidence has been well established on the ability of ß-alanine supplementation to enhance anaerobic skeletal muscle performance. As a result, ß-alanine has become one of the more popular supplements used by competitive athletes. These same benefits have also been reported in soldiers. Evidence accumulated over the last few years has suggested that ß-alanine can result in carnosine elevations in the brain, which appears to have broadened the potential effects that ß-alanine supplementation may have on soldier performance and health. Evidence suggests that ß-alanine supplementation can increase resilience to post-traumatic stress disorder, mild traumatic brain injury and heat stress. The evidence regarding cognitive function is inconclusive but may be more of a function of the stressor that is applied during the assessment period. The potential benefits of ß-alanine supplementation on soldier resiliency are interesting but require additional research using a human model. The purpose of this review is to provide an overview of the physiological role of ß-alanine and why this nutrient may enhance soldier performance.


Assuntos
Carnosina , Militares , Humanos , Carnosina/farmacologia , Exercício Físico/fisiologia , Suplementos Nutricionais , beta-Alanina/farmacologia , Cognição , Músculo Esquelético/metabolismo
3.
Nutrients ; 14(9)2022 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35565859

RESUMO

The effect of 3 weeks of amorphous calcium carbonate (ACC) supplementation (2000 mg per day) was examined on the recovery response to resistance exercise. Thirty men were randomized into a supplement (ACC) or placebo (PL) group. Following supplementation, participants performed six sets of 10 repetitions in the bench press (BP) and incline BP exercises, using 80% of maximal strength. Participants returned 24 (T4) and 48 h (T5) later and performed six sets of the BP exercise. Significant decreases in the number of repetitions (p < 0.001), peak power (p < 0.001), and mean power (p = 0.009) were noted over time, but no significant interactions were observed (p > 0.05). Magnitude-based inference analysis (MBI) indicated that the change in repetitions was possibly beneficial for ACC at T4 and likely beneficial at T5. No significant interaction was noted for general soreness (p = 0.452), but a trend toward an interaction was observed in upper body soreness (p = 0.089). Confidence intervals for mean percent change scores indicated significant differences between the groups at T4 and T5, and MBI analysis indicated that ACC was very likely or likely to be beneficial for reducing soreness at those time points. In conclusion, ACC supplementation may have a potential beneficial effect in attenuating the decline in performance, which is possibly due to the carbonate component.


Assuntos
Treinamento Resistido , Carbonato de Cálcio , Suplementos Nutricionais , Método Duplo-Cego , Exercício Físico/fisiologia , Humanos , Masculino , Força Muscular , Músculo Esquelético
4.
J Strength Cond Res ; 33(9): 2330-2337, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31306390

RESUMO

Hoffman, JR, Hoffman, MW, Zelicha, H, Gepner, Y, Willoughby, DS, Feinstein, U, and Ostfeld, I. The Effect of 2-Weeks of Inactivated Probiotic Bacillus coagulans on Endocrine, Inflammatory and Performance Responses During Self-Defense Training in Soldiers. J Strength Cond Res 33(9): 2330-2337, 2019-The effect of 2 weeks of inactivated Bacillus coagulans (iBC) ingestion on performance and inflammatory cytokines was examined during a self-defense course in soldiers. Sixteen male soldiers were randomly assigned to either iBC (n = 8) or placebo (PL; n = 8) in this double-blind study. Participants were garrisoned on base and participated in the same training tasks. Assessments were conducted in a single day before (PRE) and after the supplementation period (POST). During each testing session, participants were assessed for vertical jump power (VJP), muscle endurance, simulated casualty drag, and 2 100-m shuttle runs. Resting blood measures for testosterone, cortisol, creatine kinase, and inflammatory cytokines were also assessed. Mann-Whitney analysis of change (Δ) scores indicated no significant change (p's > 0.05) in any of the performance or blood variables. However, a trend (p = 0.089) was noted in the Δ score for VJP in iBC compared with PL. In addition, trends were observed in the change in IL-10 (p = 0.057) and IFNγ (p = 0.057). Magnitude based inferential analysis indicated that changes in VJP and simulated casualty drag were likely beneficial (90.7 and 80.4% likelihood effect, respectively) for iBC. In addition, iBC supplementation very likely augmented IL-10 concentrations, but was possibly negative for changes in IL-6, and likely negative for changes in TNFα and IFNγ. Changes in all other performance and blood markers were unclear. Results indicated that 2 weeks of iBC supplementation appeared to be beneficial for maintaining power and short-term speed performance, while attenuating the inflammatory response during intense training in a military self-defense course.


Assuntos
Bacillus coagulans , Citocinas/sangue , Exercício Físico/fisiologia , Artes Marciais/fisiologia , Militares , Probióticos/farmacologia , Creatina Quinase/sangue , Método Duplo-Cego , Humanos , Hidrocortisona/sangue , Inflamação/sangue , Interferon gama/sangue , Interleucina-10/sangue , Interleucina-6/sangue , Israel , Masculino , Artes Marciais/educação , Força Muscular/efeitos dos fármacos , Resistência Física/efeitos dos fármacos , Corrida , Testosterona/sangue , Fator de Necrose Tumoral alfa/sangue , Adulto Jovem
5.
J Spec Oper Med ; 18(4): 92-96, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30566730

RESUMO

We examined the effect of a proprietary spearmint extract containing rosmarinic acid (PSE) on physical, cognitive, and executive functioning of study participants after a high-risk tactical operation while sleep deprived for 24 hours. Ten Operators (mean ± standard deviation: age, 35.1 ± 5.2 years; height, 177.6 ± 5.3cm; weight, 81.3 ± 9.3kg) from an elite counterterrorism unit volunteered to participate in this randomized, double-blind, parallel-design study. Participants were randomly assigned into either the PSE or placebo (PL) group and ingested 900mg/day PSE or an equivalent amount of PL for 17 days. Physical, cognitive, and executive functioning was tested before PST supplementation (PRE) and within 1 hour of the operation's conclusion (POST). Magnitude-based inferences indicated that differences between PSE and PL in jump power, reactive agility, eye-hand coordination, and cognition were unclear. However, subjective feelings of energy, alertness, and focus were very likely, likely, and possibly better for PSE than PL, respectively. There was no difference (ρ = .64) between groups in identifying the correct target; however, all participants in the PSE group correctly identified the target, whereas 60% of participants in the PL group correctly identified the target at POST. Although the results of this study do not provide conclusive evidence regarding the efficacy of PSE, they do suggest additional research is warranted in a larger sample of participants.


Assuntos
Cinamatos/farmacologia , Depsídeos/farmacologia , Função Executiva/efeitos dos fármacos , Mentha spicata , Militares/psicologia , Desempenho Físico Funcional , Extratos Vegetais/farmacologia , Guerra , Adulto , Método Duplo-Cego , Humanos , Militares/estatística & dados numéricos , Ácido Rosmarínico
6.
J Strength Cond Res ; 32(10): 2978-2981, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29746388

RESUMO

Hoffman, JR, Gepner, Y, Hoffman, M, Zelicha, H, Shapira, S, and Ostfeld, I. Effect of high dose, short-duration ß-alanine supplementation on circulating IL-10 concentrations during intense military training. J Strength Cond Res 32(10): 2978-2981, 2018-This study examined the effect of ß-alanine as a potential anti-inflammatory agent during intense military training. Twenty soldiers (20.1 ± 0.6 years) from an elite combat unit were randomly assigned to either a ß-Alanine (BA) or placebo (PL) group. Soldiers were provided with 12 g·d of either BA or PL for 7 days between 2 intensive periods of navigational training and restricted sleep. During the initial training period, soldiers navigated on average 27.8 km·d with ∼50% of their body mass in their packs for 5 days. Soldiers returned to base and began a 7-day supplementation program before departing for an additional period of intense field training. During the second period of field training, soldiers navigated 10 km·d for an additional 5 days, carrying similar loading as the initial week, performed tactical missions, and slept approximately 5 hours per day. Blood samples were obtained after the initial training period and after the second training period and analyzed for IL-10. Magnitude-based inferences that were used to provide inferences on the true effect BA may have had on IL-10 concentrations compared with PL, calculated from 90% confidence intervals. Data analysis indicated that changes in circulating IL-10 concentrations (mean difference 0.86 pg·ml) were possibly greater (57%) for BA than PL. Results of this study suggest that 1 week of high-dose BA ingestion may enhance the anti-inflammatory response during intense military training, suggesting a potential therapeutic role of BA during intense training.


Assuntos
Anti-Inflamatórios/administração & dosagem , Suplementos Nutricionais , Exercício Físico , Interleucina-10/sangue , Militares , beta-Alanina/administração & dosagem , Método Duplo-Cego , Humanos , Israel , Masculino , Adulto Jovem
7.
J Appl Physiol (1985) ; 123(1): 11-18, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28408697

RESUMO

The purpose of this study was to compare the coadministration of the probiotic Bacillus coagulans GBI-30, 6086 (BC30) with ß-hydroxy-ß-methylbutyrate (HMB) calcium (CaHMB) to CaHMB alone on inflammatory response and muscle integrity during 40 days of intense military training. Soldiers were randomly assigned to one of two groups: CaHMB with BC30 (CaHMBBC30; n = 9) or CaHMB with placebo (CaHMBPL, n = 9). A third group of participants served as a control (CTL; n = 8). During the first 28 days soldiers were garrisoned on base and participated in the same training tasks. During the final 2 wk soldiers navigated 25-30 km per night in difficult terrain carrying ~35 kg of equipment. All assessments (blood draws and diffusion tensor imaging to assess muscle integrity) were conducted before and ~12 h after final supplement consumption. Analysis of covariance was used to analyze all blood and muscle measures. Significant attenuations were noted in IL-1ß, IL-2, IL-6, CX3CL1, and TNF-α for both CaHMBBC30 and CaHMBPL compared with CTL. Plasma IL-10 concentrations were significantly attenuated for CaHMBBC30 compared with CTL only. A significant decrease in apparent diffusion coefficients was also observed for CaHMBBC30 compared with CaHMBPL. Results provide further evidence that HMB supplementation may attenuate the inflammatory response to intense training and that the combination of the probiotic BC30 with CaHMB may be more beneficial than CaHMB alone in maintaining muscle integrity during intense military training.NEW & NOTEWORTHY ß-Hydroxy-ß-methylbutyrate (HMB) in its free acid form was reported to attenuate inflammation and maintain muscle integrity during military training. However, this formulation was difficult to maintain in the field. In this investigation, soldiers ingested HMB calcium (CaHMB) with Bacillus coagulans (BC30) or CaHMB alone during 40 days of training. Results indicated that CaHMB attenuated the inflammatory response and that BC30 combined with CaHMB may be more beneficial than CaHMB alone in maintaining muscle integrity during intense military training.


Assuntos
Bacillus coagulans , Citocinas/sangue , Suplementos Nutricionais , Exercício Físico/fisiologia , Militares , Músculo Esquelético/metabolismo , Valeratos/administração & dosagem , Imagem de Tensor de Difusão/métodos , Método Duplo-Cego , Quimioterapia Combinada , Humanos , Masculino , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/efeitos dos fármacos , Probióticos/administração & dosagem , Adulto Jovem
8.
Amino Acids ; 49(5): 871-886, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28161798

RESUMO

This study investigated the benefit of ß-alanine (BA) supplementation on behavioral and cognitive responses relating to mild traumatic brain injury (mTBI) and post-traumatic stress disorder (PTSD) in rats exposed to a low-pressure blast wave. Animals were fed a normal diet with or without (PL) BA supplementation (100 mg kg-1) for 30-day, prior to being exposed to a low-pressure blast wave. A third group of animals served as a control (CTL). These animals were fed a normal diet, but were not exposed to the blast. Validated cognitive-behavioral paradigms were used to assess both mTBI and PTSD-like behavior on days 7-14 following the blast. Brain-derived neurotrophic factor (BDNF), neuropeptide Y, glial fibrillary acidic protein (GFAP) and tau protein expressions were analyzed a day later. In addition, brain carnosine and histidine content was assessed as well. The prevalence of animals exhibiting mTBI-like behavior was significantly lower (p = 0.044) in BA than PL (26.5 and 46%, respectively), but no difference (p = 0.930) was noted in PTSD-like behavior between the groups (10.2 and 12.0%, respectively). Carnosine content in the cerebral cortex was higher (p = 0.048) for BA compared to PL, while a trend towards a difference was seen in the hippocampus (p = 0.058) and amygdala (p = 0.061). BDNF expression in the CA1 subregion of PL was lower than BA (p = 0.009) and CTL (p < 0.001), while GFAP expression in CA1 (p = 0.003) and CA3 (p = 0.040) subregions were higher in PL than other groups. Results indicated that BA supplementation for 30-day increased resiliency to mTBI in animals exposed to a low-pressure blast wave.


Assuntos
Traumatismos por Explosões/metabolismo , Lesões Encefálicas/metabolismo , Suplementos Nutricionais , Transtornos de Estresse Pós-Traumáticos/metabolismo , Transtornos de Estresse Pós-Traumáticos/prevenção & controle , beta-Alanina/administração & dosagem , Animais , Traumatismos por Explosões/genética , Traumatismos por Explosões/fisiopatologia , Química Encefálica , Lesões Encefálicas/genética , Lesões Encefálicas/fisiopatologia , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Carnosina/metabolismo , Expressão Gênica , Proteína Glial Fibrilar Ácida/genética , Proteína Glial Fibrilar Ácida/metabolismo , Histidina/metabolismo , Masculino , Neuropeptídeo Y/genética , Neuropeptídeo Y/metabolismo , Ratos , Ratos Sprague-Dawley , Transtornos de Estresse Pós-Traumáticos/genética , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Proteínas tau/genética , Proteínas tau/metabolismo
9.
J Neurotrauma ; 34(1): 145-164, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-26885687

RESUMO

The intense focus in the clinical literature on the mental and neurocognitive sequelae of explosive blast-wave exposure, especially when comorbid with post-traumatic stress-related disorders (PTSD) is justified, and warrants the design of translationally valid animal studies to provide valid complementary basic data. We employed a controlled experimental blast-wave paradigm in which unanesthetized animals were exposed to visual, auditory, olfactory, and tactile effects of an explosive blast-wave produced by exploding a thin copper wire. By combining cognitive-behavioral paradigms and ex vivo brain MRI to assess mild traumatic brain injury (mTBI) phenotype with a validated behavioral model for PTSD, complemented by morphological assessments, this study sought to examine our ability to evaluate the biobehavioral effects of low-intensity blast overpressure on rats, in a translationally valid manner. There were no significant differences between blast- and sham-exposed rats on motor coordination and strength, or sensory function. Whereas most male rats exposed to the blast-wave displayed normal behavioral and cognitive responses, 23.6% of the rats displayed a significant retardation of spatial learning acquisition, fulfilling criteria for mTBI-like responses. In addition, 5.4% of the blast-exposed animals displayed an extreme response in the behavioral tasks used to define PTSD-like criteria, whereas 10.9% of the rats developed both long-lasting and progressively worsening behavioral and cognitive "symptoms," suggesting comorbid PTSD-mTBI-like behavioral and cognitive response patterns. Neither group displayed changes on MRI. Exposure to experimental blast-wave elicited distinct behavioral and morphological responses modelling mTBI-like, PTSD-like, and comorbid mTBI-PTSD-like responses. This experimental animal model can be a useful tool for elucidating neurobiological mechanisms underlying the effects of blast-wave-induced mTBI and PTSD and comorbid mTBI-PTSD.


Assuntos
Traumatismos por Explosões/diagnóstico por imagem , Concussão Encefálica/diagnóstico por imagem , Modelos Animais de Doenças , Transtornos de Estresse Pós-Traumáticos/diagnóstico por imagem , Animais , Ansiedade/diagnóstico por imagem , Ansiedade/etiologia , Ansiedade/psicologia , Traumatismos por Explosões/complicações , Traumatismos por Explosões/psicologia , Concussão Encefálica/complicações , Concussão Encefálica/psicologia , Comorbidade , Masculino , Aprendizagem em Labirinto/fisiologia , Pressão/efeitos adversos , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Transtornos de Estresse Pós-Traumáticos/etiologia , Transtornos de Estresse Pós-Traumáticos/psicologia
10.
Growth Horm IGF Res ; 32: 55-59, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27726925

RESUMO

OBJECTIVE: Insulin-like growth factor-I (IGF-I) is a metabolic and anabolic biomarker that has been proposed to reflect physiological adaptations resulting from multistressor environments. The bioactivity of IGF-I is regulated by seven different insulin-like growth factor binding proteins (IGFBPs) which act not only as carriers of IGF-1, but also function as a modulator of IGF-I availability and activity. Supplementing with ß-hydroxy-ß-methylbutyrate (HMB) has been shown to enhance physiological outcomes associated with intense training, and has been reported to augment the IGF-1 response. The purpose of this study was to examine the effect of 23days of HMB supplementation on circulating levels of IGF-I and IGFBPs in combat soldiers during highly intense military training. METHODS: Thirteen male soldiers from an elite infantry unit volunteered to participate in this double-blind, parallel design study. Soldiers were provided 3g·day-1 of either HMB (n=6) or placebo (PL; n=7). During the study soldiers performed advanced military training with periods of restricted sleep and severe environmental stressors. Blood samples were obtained prior to (PRE) and approximately 18h following the final supplement consumption (POST). RESULTS: No significant differences were observed for circulating IGF-1 concentrations between HMB and PL (p=0.568). In addition, no differences were seen between the groups for IGFBP-1 (p=1.000), IGFBP-2 (p=0.855), IGFBP-3 (p=0.520), IGFBP-4 (p=0.103), IGFBP-5 (p=0.886), or IGFBP-6 (p=0.775). A significant difference was noted between HMB (169.9±23.0ng·ml-1) and PL (207.2±28.0ng·ml-1) for IGFBP-7 at POST (p=0.042). CONCLUSIONS: Although the results of this study do not support the influence of HMB supplementation on circulating concentrations of IGF-1 or IGFBPs1-6 during high intensity military training, it does present initial evidence that it may lower circulating IGFBP-7 concentrations. This may provide some indication of a reduced stress response, but further investigation on the physiological role of IGFBP-7 and military training is needed.


Assuntos
Suplementos Nutricionais , Exercício Físico/fisiologia , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/sangue , Fator de Crescimento Insulin-Like I/análise , Militares , Valeratos/administração & dosagem , Adulto , Método Duplo-Cego , Ingestão de Alimentos , Humanos , Masculino , Adulto Jovem
11.
Nutr Res ; 36(6): 553-63, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27188901

RESUMO

This study tested the hypothesis that of 23 days of ß-hydroxy-ß-methylbutyrate (HMB) supplementation can maintain muscle mass and attenuate the immune and inflammatory response in combat soldiers during highly intense military training. Soldiers were randomly assigned to either a HMB (n = 6) or placebo (PL; n = 7) group and provided with 3 g · day(-1) of either HMB or PL. During the final week of supplementation soldiers participated in extreme physical training, which included night navigation of 6-8 hours across difficult terrain carrying heavy loads combined with sleep deprivation (3.8 ± 3.0 h per night). Blood draws were performed prior to and following the supplementation period. Magnetic resonance imaging, which included diffusion tensor imaging sequence, was used for muscle fiber tracking analysis. Data was analyzed using a two-way mixed factorial analysis of variance. Magnitude-based inferences were used to provide inferences on the true effects that HMB may have had on the dependent variables compared to PL, calculated from 90% confidence intervals. Changes in tumor necrosis factor-α for HMB (-3.9 ± 8.2 pg · mL(-1)) were significantly lower (P = .043) compared to the change in PL (+4.0 ± 3.7 pg · mL(-1)). HMB ingestion was also very likely (92%-95% Likelihood) to lower granulocyte colony-stimulating factor and interleukin 10 compared to PL. In addition, HMB supplementation was likely (78%-87% likelihood) to reduce interferon-γ, interleukin 8, CX3CL1, and increase muscle volume for the adductor magnus (77% likelihood) compared to PL. In summary, the results of this study provides evidence that HMB supplementation may attenuate the inflammatory response to high intense military training, and maintain muscle quality.


Assuntos
Citocinas/sangue , Suplementos Nutricionais , Exercício Físico , Militares , Valeratos/administração & dosagem , Quimiocina CX3CL1/metabolismo , Creatina Quinase/sangue , Imagem de Tensor de Difusão , Método Duplo-Cego , Humanos , L-Lactato Desidrogenase/sangue , Imageamento por Ressonância Magnética , Masculino , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Cooperação do Paciente , Resistência Física/efeitos dos fármacos
12.
Amino Acids ; 47(6): 1247-57, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25758106

RESUMO

This study investigated the effects of ß-alanine (BA) ingestion on the behavioral and neuroendocrine response of post-traumatic stress disorder (PTSD) in a murine model. Animals were fed a normal diet with or without (PL) BA supplementation (100 mg kg(-1)) for 30 days. Animals were then exposed to a predator-scent stress (PSS) or a sham (UNEX). Behaviors were evaluated using an elevated plus maze (EPM) and acoustic startle response (ASR) 7 days following exposure to the PSS. Corticosterone concentrations (CS), expression of brain-derived neurotrophic factor (BDNF), and brain carnosine concentrations were analyzed a day later. Animals in PSS+PL spent significantly less time in the open arms and in the number of entries in the EPM than PSS+BA, UNEX+BA, or UNEX+PL. Animals in PSS+BA had comparable scores to UNEX+BA. Anxiety index was higher (p < 0.05) in PSS+PL compared to PSS+BA or animals that were unexposed. ASR and freezing were greater (p < 0.05) in animals exposed to PSS compared to animals unexposed. CS expression was higher (p < 0.05) in animals exposed to PSS compared to unexposed animals. Brain carnosine concentrations in the hippocampus and other brain sections were significantly greater in animals supplemented with BA compared to PL. BDNF expression in the CA1 and DG subregions of the hippocampus was lower (p < 0.05) in animals exposed and fed a normal diet compared to animals exposed and supplemented with BA, or animals unexposed. In conclusion, BA supplementation in rats increased brain carnosine concentrations and resulted in a reduction in PTSD-like behavior, which may be mediated in part by maintaining BDNF expression in the hippocampus.


Assuntos
Comportamento Animal/efeitos dos fármacos , Suplementos Nutricionais , Transtornos de Estresse Pós-Traumáticos , Estresse Psicológico , beta-Alanina/farmacologia , Animais , Modelos Animais de Doenças , Masculino , Ratos , Ratos Sprague-Dawley , Transtornos de Estresse Pós-Traumáticos/dietoterapia , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Estresse Psicológico/dietoterapia , Estresse Psicológico/fisiopatologia
13.
Amino Acids ; 47(3): 627-36, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25510839

RESUMO

The purpose of this study was to examine the effect of ß-alanine (BA) ingestion on tissue carnosine levels and the impact such changes would have on combat specific activity. Eighteen soldiers (19.9 ± 0.8 year) from an elite combat unit were randomly assigned to either a BA or placebo (PL) group. Before and following a 30-day supplementation period carnosine content of the gastrocnemius muscle and brain was determined by proton magnetic resonance spectroscopy. During each testing session, participants performed military relevant tasks that included a 2.5 km run, a 1-min sprint, 50-m casualty carry, repeated 30-m sprints with target shooting, and a 2-min serial subtraction test (SST) to assess cognitive function under stressful conditions. A significant elevation (p = 0.048) in muscle carnosine content was noted in BA compared to PL. Changes in muscle carnosine content was correlated to changes in fatigue rate (r = 0.633, p = 0.06). No changes (p = 0.607) were observed in brain carnosine content. Following supplementation, no differences were noted in 2.5 km run, 1-min sprint, repeated sprint, or marksmanship performance, but participants in BA significantly (p = 0.044) improved their time for the 50-m casualty carry and increased their performance (p = 0.022) in the SST compared to PL. In summary, 30-days of BA ingestion can increase muscle carnosine content and improve aspects of military specific performance. Although cognitive performance was significantly greater in participants consuming BA compared to placebo, current study methods were unable to detect any change in brain carnosine levels, thus, the precise mechanism underlying these effects remains elusive.


Assuntos
Carnosina/metabolismo , Militares , Músculo Esquelético/metabolismo , Resistência Física/efeitos dos fármacos , beta-Alanina/administração & dosagem , Adulto , Humanos , Masculino
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