RESUMEN
Nearly half of the world's population is at risk of being infected by Plasmodium falciparum, the pathogen of malaria. Increasing resistance to common antimalarial drugs has encouraged investigations to find compounds with different scaffolds. Extracts of Artocarpus altilis leaves have previously been reported to exhibit in vitro antimalarial activity against P. falciparum and in vivo activity against P. berghei. Despite these initial promising results, the active compound from A. altilis is yet to be identified. Here, we have identified 2-geranyl-2', 4', 3, 4-tetrahydroxy-dihydrochalcone (1) from A. altilis leaves as the active constituent of its antimalarial activity. Since natural chalcones have been reported to inhibit food vacuole and mitochondrial electron transport chain (ETC), the morphological changes in food vacuole and biochemical inhibition of ETC enzymes of (1) were investigated. In the presence of (1), intraerythrocytic asexual development was impaired, and according to the TEM analysis, this clearly affected the ultrastructure of food vacuoles. Amongst the ETC enzymes, (1) inhibited the mitochondrial malate: quinone oxidoreductase (PfMQO), and no inhibition could be observed on dihydroorotate dehydrogenase (DHODH) as well as bc1 complex activities. Our study suggests that (1) has a dual mechanism of action affecting the food vacuole and inhibition of PfMQO-related pathways in mitochondria.
Asunto(s)
Antimaláricos , Artocarpus , Chalconas , Malaria Falciparum , Humanos , Plasmodium falciparum , Chalconas/farmacología , Chalconas/uso terapéutico , Antimaláricos/farmacología , Antimaláricos/uso terapéutico , Artocarpus/química , Artocarpus/metabolismo , Malatos/metabolismo , Malatos/farmacología , Malatos/uso terapéutico , Extractos Vegetales/farmacología , Extractos Vegetales/química , Malaria Falciparum/tratamiento farmacológico , Mitocondrias/metabolismo , Quinonas/farmacologíaRESUMEN
ABSTRACT: Gills, JL, Spliker, B, Glenn, JM, Szymanski, D, Romer, B, Lu, H-C, and Gray, M. Acute citrulline-malate supplementation increases total work in short lower-body isokinetic tasks for recreationally active females during menstruation. J Strength Cond Res 37(6): 1225-1230, 2023-Citrulline-malate (CM) exhibits acute ergogenic benefits through nitric oxide production (NO) and augmentation of vasodilatory properties. Nitric oxide is upregulated by estrogen and may influence CM's ergogenic efficacy in women. Therefore, the objective of this study was to evaluate the acute effects of CM supplementation on lower-body isokinetic performance in recreationally active women. Nineteen women (23.5 ± 3.1 years; 164.8 ± 7.0 cm; 61.9 ± 27.4 kg; 28.8 ± 8.1% body fat) completed 2 randomized, double-blind, crossover trials consuming CM (8 g CM + 12 g dextrose) or placebo (12 g dextrose). For testing trials, subjects were in the menstruating portion of the follicular phase of their menstrual cycle. Subjects performed a 5-repetition isokinetic leg extension protocol (5RP) followed by a 50-repetition isokinetic leg extension protocol (50RP), 60 minutes after supplement consumption. Repeated measures analysis of variance analysis showed that CM significantly increased total work completed, relative total work, and total work during maximum repetition compared with placebo ( p < 0.05); but no significant performance differences existed between trials for peak torque production ( p = 0.14) for the 5RP. No significant differences were identified between trials for peak torque production ( p = 0.69 ) or total work ( p = 0.33) completed during the 50RP. CM increased total work completed during the 5RP, but provided no ergogenic benefit during the 50RP in recreationally active menstruating women. CM amplifies power-based resistance exercise performance in women during the follicular phase of the menstrual cycle, potentially because of depressed estrogen levels. Additional research is needed to identify timing efficacy of CM to increase sport performance during each phase of the menstrual cycle.
Asunto(s)
Rendimiento Atlético , Menstruación , Humanos , Femenino , Citrulina/farmacología , Malatos/farmacología , Óxido Nítrico , Suplementos Dietéticos , Método Doble Ciego , Glucosa/farmacología , Músculo EsqueléticoRESUMEN
How do neurons match generation of adenosine triphosphate by mitochondria to the bioenergetic demands of regenerative activity? Although the subject of speculation, this coupling is still poorly understood, particularly in neurons that are tonically active. To help fill this gap, pacemaking substantia nigra dopaminergic neurons were studied using a combination of optical, electrophysiological, and molecular approaches. In these neurons, spike-activated calcium (Ca2+) entry through Cav1 channels triggered Ca2+ release from the endoplasmic reticulum, which stimulated mitochondrial oxidative phosphorylation through two complementary Ca2+-dependent mechanisms: one mediated by the mitochondrial uniporter and another by the malate-aspartate shuttle. Disrupting either mechanism impaired the ability of dopaminergic neurons to sustain spike activity. While this feedforward control helps dopaminergic neurons meet the bioenergetic demands associated with sustained spiking, it is also responsible for their elevated oxidant stress and possibly to their decline with aging and disease.
Asunto(s)
Calcio , Neuronas Dopaminérgicas , Adenosina Trifosfato/metabolismo , Ácido Aspártico , Calcio/metabolismo , Neuronas Dopaminérgicas/metabolismo , Malatos/metabolismo , Malatos/farmacología , Mitocondrias/metabolismo , Oxidantes , Sustancia Negra/metabolismoRESUMEN
Polymalic acid (PMA) is a water-soluble polyester produced by Aureobasidium pullulans. In this study, the physiological response of A. pullulans after the addition of vegetable oils was investigated. Soybean oil (SBO) is pivotal for shortening fermentation time and achieving high PMA titer. With the addition of 1% (w/v) SBO, the titer and productivity of PMA was, respectively, increased by 34.2% and 80%. SBO acted as a chemical stimulatory agent rather than a carbon source, the enhancement on PMA production was attributed to the component of fatty acid. SBO induced the dimorphism (yeast-like cells and mycelia) of A. pullulans, in vitro enzyme activities indicated that the TCA oxidative branch for malic acid synthesis might be strengthened, which could generate more ATP for PMA synthesis, and the assay of intracellular energy supply validated this deduction. This study provided a new sight for recognizing the regulatory behavior of SBO in A. pullulans.
Asunto(s)
Ascomicetos , Aceite de Soja , Adenosina Trifosfato , Aureobasidium , Carbono/farmacología , Ácidos Grasos , Fermentación , Malatos/farmacología , Poliésteres , Polímeros , Aceite de Soja/farmacología , AguaRESUMEN
As a nitric oxide (NO) enhancer, citrulline malate (CM) has recently been touted as a potential ergogenic aid to both resistance and high-intensity exercise performance, as well as the recovery of muscular performance. The mechanism has been associated with enhanced blood flow to active musculature, however, it might be more far-reaching as either ammonia homeostasis could be improved, or ATP production could be increased via greater availability of malate. Moreover, CM might improve muscle recovery via increased nutrient delivery and/or removal of waste products. To date, a single acute 8 g dose of CM on either resistance exercise performance or cycling has been the most common approach, which has produced equivocal results. This makes the effectiveness of CM to improve exercise performance difficult to determine. Reasons for the disparity in conclusions seem to be due to methodological discrepancies such as the testing protocols and the associated test-retest reliability, dosing strategy (i.e., amount and timing), and the recent discovery of quality control issues with some manufacturers stated (i.e., citrulline:malate ratios). Further exploration of the optimal dose is therefore required including quantification of the bioavailability of NO, citrulline, and malate following ingestion of a range of CM doses. Similarly, further well-controlled studies using highly repeatable exercise protocols with a large aerobic component are required to assess the mechanisms associated with this supplement appropriately. Until such studies are completed, the efficacy of CM supplementation to improve exercise performance remains ambiguous.
Asunto(s)
Rendimiento Atlético , Citrulina/análogos & derivados , Malatos/farmacología , Sustancias para Mejorar el Rendimiento/farmacología , Citrulina/farmacología , Suplementos Dietéticos , HumanosRESUMEN
This study was conducted to evaluate the antibacterial effect of 460-470 nm light-emitting diodes illumination (460/470 LED) combined with various antimicrobials at inactivating Escherichia coli O157:H7 and identify the antibacterial mechanisms. When carvacrol, thymol, citric acid, malic acid, citrus fruit extract, 3% NaCl, or 5% NaCl was combined with 460/470 LED, there was a higher reduction in E. coli O157:H7 compared to 460/470 LED treatment or antimicrobials alone at 4 °C. Particularly, a marked synergistic effect (>8.74 log10 CFU/ml) was observed when 460/470 LED was combined with carvacrol, malic acid, citrus fruit extract, or 3% NaCl. Levels of intracellular ROS and lipid peroxidation of E. coli O157:H7 were higher in the combination of 460/470 LED and antimicrobials compared to individual treatments. Moreover, the combination treatment increased depolarization of the cell membrane leading to membrane damage as well as the loss of DNA integrity. Thus, adding antimicrobial treatment to 460/470 LED could improve its efficacy against pathogenic bacteria such as E. coli O157:H7.
Asunto(s)
Antibacterianos/química , Citrus/química , Cimenos/química , Escherichia coli/efectos de los fármacos , Malatos/química , Extractos Vegetales/química , Antibacterianos/farmacología , Terapia Combinada , Cimenos/farmacología , Humanos , Luz , Peroxidación de Lípido , Malatos/farmacología , Pruebas de Sensibilidad Microbiana , Fototerapia , Extractos Vegetales/farmacología , Exposición a la Radiación , Especies Reactivas de Oxígeno/químicaRESUMEN
To control Pseudomonas and Shewanella as important psychrotrophic spoilage bacteria in fish meat, we used ethanolic extracts of oregano (Origanum vulgare subsp. vulgare) and nettle (Urtica dioica), with phytochemical characterisation of the extracts and their bioactive compounds. Liquid chromatography coupled with photodiode array detection and electrospray ionisation-mass spectrometry was used for qualitative compositional determination of the extracts. Four main compounds were identified in the oregano extract, with rosmarinic acid the most abundant, followed by three glycosylated phenolics, one of which is reported for the first time in O. vulgare: 4'-O-ß-d-glucopyranosyl-3',4'-dihydroxybenzyl-4-hydroxybenzoate. Six main compounds were identified in the nettle extract, as caffeoylmalic acid and five flavonoid glycosides. These oregano and nettle ethanolic extracts showed in-vitro antimicrobial activities against selected Pseudomonas and Shewanella strains in broth and fish meat homogenate when evaluated at two inoculum concentrations. The antimicrobial activities were more pronounced for the nettle extract at the lower inoculum concentration, and for both the Shewanella strains. Growth inhibition in the fish meat homogenate was evaluated at 3.13â¯mg/mL and 1.56â¯mg/mL at 5⯰C. Again, the nettle extract showed greater antimicrobial activity, which was seen as the lowest maximum growth rate, followed by the oregano extract, which was inhibitory only at 3.13â¯mg/mL. Finally, the extracts were applied to fish meat that was then stored at 5⯰C for 9â¯days. Evaluation here was for the counts of the mesophilic, psychrotrophic, Pseudomonas and H2S producers. These confirmed the better antimicrobial effects of the nettle extract, especially against the H2S-producing bacteria, which included Shewanella. Both of the extracts were rich in glycosides of flavonoids and phenolic acids. The enzymatic activities of the Pseudomonas and Shewanella spoilage bacteria and their actions on the phenolic glycosides from natural sources will be further investigated.
Asunto(s)
Enfermedades de los Peces/tratamiento farmacológico , Origanum/química , Extractos Vegetales/farmacología , Pseudomonas/efectos de los fármacos , Shewanella/efectos de los fármacos , Urtica dioica/química , Animales , Ácidos Cafeicos/farmacología , Cinamatos/farmacología , Depsidos/farmacología , Peces/microbiología , Flavonoides , Microbiología de Alimentos , Hidroxibenzoatos/farmacología , Malatos/farmacología , Fenoles/química , Alimentos Marinos/microbiología , Espectrometría de Masa por Ionización de Electrospray , Ácido RosmarínicoRESUMEN
We evaluated the antioxidant and skin-lightening activities of 4-hydroxycinnamoyl-malate (4-HCM) in vitro; the material is a water-soluble component of Citrus junos callus. 4-HCM was waterextracted from callus grown on MS medium containing picloram to enhance growth. The antioxidant activity of 4-HCM was determined using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azinobis-(3-ethylbenzoline-6-sulfonate) (ABTS) free-radical-scavenging assays. 4-HCM-mediated inhibition of extracellular matrix protein glycation was assessed using the elastin and collagen glycation assays. Inhibition of skin pigmentation was evaluated by measuring anti-tyrosinase activity and melanogenesis in melanoma cells. 4-HCM was then incorporated into elastic nanoliposomes (ENLs) and delivered topically to enhance percutaneous absorption. At 5 mM, the free-radical-scavenging activity of 4-HCM was 54.2±0.631% in the ABTS assay, comparable to that of 1 mM ascorbic acid (46.5± 0.17%). The IC50 value for inhibition of advanced glycation end-product formation from elastin was 1.25±0.23 mM; collagen glycation was completely inhibited when the 4-HCM level was >5 mM. At 0.5 mM, the material afforded 49.2±3.09% inhibition of tyrosinase activity and, at 10 mM, reduced the melanocyte melanin content by 78% without significant cellular toxicity. Moreover, 4-HCM-loaded ENLs exhibited 569% enhanced permeation of 4-HCM across the human epidermis, which may afford skin-lightening if included in cosmetic formulations.
Asunto(s)
Antioxidantes/farmacología , Citrus , Malatos/farmacología , Monofenol Monooxigenasa/antagonistas & inhibidores , Extractos Vegetales/farmacología , HumanosRESUMEN
BACKGROUND: Athletes are increasingly exploring ways to enhance their physical performance. Increasing blood flow to the working tissues through endothelium-dependent vasodilation is one factor athletes use to realize these results. Sports supplements such as pre-workouts tout this benefit; however, many have not been tested under laboratory conditions to examine the effects of commonly used supplements on vasodilation. Two popular supplements are Nitrosigine® and citrulline malate (CM). Thus, the purpose of this experiment was to determine the effects of Nitrosigine and CM on vasodilation using ultrasound and flow mediated dilation (FMD). METHODS: Healthy, normotensive, and physically active male (n = 16) and female (n = 8) young adults participated in the present investigation. We utilized a randomized, double-blind, within-subjects design where participants reported for three trials, each preceded by a 7-day washout period. Baseline FMD measurement was obtained for each visit, followed by consumption of one clinical dose CM (8 g), Nitrosigine (1.5 g), or dextrose placebo (8 g). Following a 60-min digestion period, FMD was repeated. Supplementation order was randomized controlling for potential order effects. RESULTS: Repeated measures ANOVA yielded a significant supplement (3) x time (2) effect (p < .001), such that Nitrosigine and CM yielded a greater improvement in FMD response than placebo. After supplementation, Nitrosigine and CM increased FMD by 31 and 34%, respectively, compared to a decrease of 2% during the placebo trial. After allometric scaling of the FMD values, supplement x time effect remained significant (p = .001) and changes were similar to non-scaled results. Nitrosigine (23%) and CM (25%) generated significantly greater allometric scaled FMD values when compared to the placebo trial (0.60%). DISCUSSION: Both Nitrisigine and CM increased endothelial-dependent vasodilation as measured by a change in FMD. Increased vasodilation leads to an increase in skeletal muscle blood flow resulting in potential improvements in exercise performance.
Asunto(s)
Arginina/farmacología , Citrulina/análogos & derivados , Suplementos Dietéticos , Inositol/farmacología , Malatos/farmacología , Silicatos/farmacología , Vasodilatación/efectos de los fármacos , Adolescente , Adulto , Citrulina/farmacología , Estudios Cruzados , Método Doble Ciego , Combinación de Medicamentos , Femenino , Voluntarios Sanos , Humanos , Masculino , Ultrasonografía , Adulto JovenRESUMEN
Gonzalez, AM and Trexler, ET. Effects of citrulline supplementation on exercise performance in humans: A review of the current literature. J Strength Cond Res 34(5): 1480-1495, 2020-L-citrulline, a nonessential amino acid found primarily in watermelon, has recently garnered much attention for its potential to augment L-arginine bioavailability, nitric oxide production, and exercise performance. Over the past decade, L-citrulline has received considerable scientific attention examining potentially ergogenic properties for both aerobic and anaerobic exercise performance. Thus, the purpose of this article is to summarize the theoretical rationale behind L-citrulline supplementation and to comprehensively review the available scientific evidence assessing the potential ergogenic value of L-citrulline supplementation on vascular function and exercise performance in humans. In addition, research that has investigated the potential synergistic effects of L-citrulline with other dietary ingredients (e.g., arginine, antioxidants, nitrates, and branched-chain amino acids) is reviewed. Oral L-citrulline and citrulline malate supplementation have shown to increase plasma citrulline and arginine concentrations, along with total nitrate and nitrite concentrations. Although blood flow enhancement is a proposed mechanism for the ergogenic potential of L-citrulline, evidence supporting acute improvements in vasodilation and skeletal muscle tissue perfusion after supplementation is scarce and inconsistent. Nevertheless, several studies have reported that L-citrulline supplementation can enhance exercise performance and recovery. Given the positive effects observed from some investigations, future studies should continue to investigate the effects of both acute and chronic supplementation with L-citrulline and citrulline malate on markers of blood flow and exercise performance and should seek to elucidate the mechanism underlying such effects.
Asunto(s)
Citrulina/farmacología , Suplementos Dietéticos , Ejercicio Físico/fisiología , Músculo Esquelético/efectos de los fármacos , Aminoácidos de Cadena Ramificada/farmacología , Antioxidantes/farmacología , Arginina/farmacología , Biomarcadores , Citrulina/análogos & derivados , Quimioterapia Combinada , Humanos , Malatos/farmacología , Músculo Esquelético/fisiología , Nitratos/farmacologíaRESUMEN
Abstract Background: Studies have persuasively demonstrated that citrulline has a key role in the arginine-nitric oxide system, increasing nitric oxide bioavailability, an important mediator of peripheral vasodilation. Objective: To analyze the inter-individual post-exercise hypotension responsiveness following acute citrulline supplementation in hypertensives. Methods: Forty hypertensives were randomly assigned to one of the four experimental groups (control-placebo, control-citrulline, exercise-placebo, and exercise-citrulline). They ingested placebo or citrulline malate [CM] (6 grams). During the exercise session, individuals performed 40 minutes of walking/running on a treadmill at 60-70% of HR reserve. For the control session, the individuals remained seated at rest for 40 minutes. Office blood pressure (BP) was taken every 10 minutes until completing 60 minutes after the experimental session. The ambulatory BP device was programmed to take the readings every 20 minutes (awake time) and every 30 minutes (sleep time) over the course of 24 hours of monitoring. Statistical significance was defined as p < 0.05. Results: Unlike the other experimental groups, there were no "non-responders" in the exercise/citrulline (EC) for "awake" (systolic and diastolic BP) and "24 hours" (diastolic BP). The effect sizes were more consistent in the EC for systolic and diastolic ambulatorial BP response. The effects were "large" (> 0.8) for "awake", "asleep", and "24 hours" only in the EC for diastolic BP. Conclusion: CM supplementation can increase the post-exercise hypotensive effects in hypertensives. In addition, the prevalence of non-responders is lower when associated with aerobic exercise and CM supplementation.
Resumo Fundamento: Estudos demonstraram de maneira persuasiva que a citrulina tem um papel fundamental no sistema arginina-óxido nítrico, aumentando a biodisponibilidade do óxido nítrico, um importante mediador da vasodilatação periférica. Objetivo: Analisar a responsividade interindividual da hipotensão pós-exercício após suplementação aguda com citrulina em hipertensos. Métodos: Quarenta hipertensos foram aleatoriamente designados para um dos quatro grupos experimentais (controle-placebo, controle-citrulina, exercício-placebo e exercício-citrulina). Eles ingeriram placebo ou citrulina malato [CM] (6 gramas). Durante a sessão de exercício, os indivíduos realizaram 40 minutos de caminhada/corrida em esteira a 60-70% da FC de reserva. Para a sessão de controle, os indivíduos permaneceram sentados em repouso por 40 minutos. A medida da pressão arterial (PA) no consultório foi realizada a cada 10 minutos até completar 60 minutos após a sessão experimental. O dispositivo ambulatorial de PA foi programado para fazer as leituras a cada 20 minutos (tempo de vigília) e a cada 30 minutos (tempo de sono) ao longo de 24 horas de monitoramento. A significância estatística foi definida como p < 0,05. Resultados: Diferentemente de outros grupos experimentais, não houve "não respondedores" no exercício/citrulina (EC) para "acordado" (PA sistólica e diastólica) e "24 horas" (PA diastólica). Os tamanhos de efeito foram mais consistentes no EC para a resposta sistólica e diastólica da PA ambulatorial. Os efeitos foram "grandes" (> 0,8) para "acordado", "dormindo", e para "24 horas" apenas no EC para a PA diastólica. Conclusão: A suplementação com CM pode aumentar os efeitos hipotensivos pós-exercício em hipertensos. Além disso, a prevalência de "não respondedores" é menor quando associada ao exercício aeróbico e à suplementação com CM.
Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Vasodilatadores/farmacología , Presión Sanguínea/efectos de los fármacos , Ejercicio Físico/fisiología , Citrulina/análogos & derivados , Hipotensión Posejercicio/fisiopatología , Hipertensión/fisiopatología , Malatos/farmacología , Arginina/metabolismo , Valores de Referencia , Factores de Tiempo , Efecto Placebo , Antropometría , Método Doble Ciego , Análisis de Varianza , Resultado del Tratamiento , Citrulina/farmacología , Estadísticas no Paramétricas , Prueba de Esfuerzo , Hipertensión/terapia , Óxido Nítrico/metabolismoRESUMEN
Trexler, ET, Keith, DS, Schwartz, TA, Ryan, ED, Stoner, L, Persky, AM, and Smith-Ryan, AE. Effects of citrulline malate and beetroot juice supplementation on blood flow, energy metabolism, and performance during maximum effort leg extension exercise. J Strength Cond Res 33(9): 2321-2329, 2019-Citrulline malate (CitMal) and beetroot juice (BEET) are increasingly popular ergogenic aids, but few studies have rigorously investigated their effects on resistance exercise performance and underlying mechanisms. The current randomized, double-blind, crossover study evaluated the effects of CitMal and BEET supplementation on blood flow, metabolic efficiency, and performance during maximal isokinetic leg extension exercise. After familiarization, 27 recreationally active men (age: 22 ± 4 years) completed 3 visits in which subjects ingested a treatment beverage (CitMal [8 g], BEET [400-mg nitrate], or placebo [PLA]), followed by a 2-hour rest period, warm-up, and 5 sets of 30 concentric leg extensions. Before and after exercise, ultrasound was used to measure diameter (aDIAM) and blood flow (aBF) of the superficial femoral artery, along with cross-sectional area and echo intensity of the vastus lateralis. Plasma analytes (lactate, nitrate/nitrite [NOx], and urea nitrogen [BUN]) were also assessed at these times, and indirect calorimetry was used to measure energy expenditure and respiratory exchange ratio before and during exercise. Resting NOx values were higher in BEET (233.2 ± 1.1 µmol·L) compared with CitMal (15.3 ± 1.1, p < 0.0001) and PLA (13.4 ± 1.1, p < 0.0001). Postexercise NOx values, adjusted for resting differences, were higher in BEET (86.3 ± 1.2 µmol·L) than CitMal (21.3 ± 1.1, p < 0.0001) and PLA (18.1 ± 1.1, p < 0.0001). No other variables were affected by treatment (all p > 0.05). While BEET increased NOx, neither treatment was found to enhance performance, blood flow, metabolic efficiency, nor the hormonal response to leg extension exercise.
Asunto(s)
Beta vulgaris , Citrulina/análogos & derivados , Jugos de Frutas y Vegetales , Malatos/farmacología , Sustancias para Mejorar el Rendimiento/farmacología , Adolescente , Adulto , Citrulina/farmacología , Estudios Cruzados , Suplementos Dietéticos , Método Doble Ciego , Metabolismo Energético/efectos de los fármacos , Ejercicio Físico/fisiología , Arteria Femoral/diagnóstico por imagen , Humanos , Masculino , Nitratos/administración & dosificación , Nitratos/sangre , Nitritos/sangre , Raíces de Plantas , Músculo Cuádriceps/irrigación sanguínea , Músculo Cuádriceps/fisiología , Flujo Sanguíneo Regional/efectos de los fármacos , Ultrasonografía , Adulto JovenRESUMEN
BACKGROUND: Studies have persuasively demonstrated that citrulline has a key role in the arginine-nitric oxide system, increasing nitric oxide bioavailability, an important mediator of peripheral vasodilation. OBJECTIVE: To analyze the inter-individual post-exercise hypotension responsiveness following acute citrulline supplementation in hypertensives. METHODS: Forty hypertensives were randomly assigned to one of the four experimental groups (control-placebo, control-citrulline, exercise-placebo, and exercise-citrulline). They ingested placebo or citrulline malate [CM] (6 grams). During the exercise session, individuals performed 40 minutes of walking/running on a treadmill at 60-70% of HR reserve. For the control session, the individuals remained seated at rest for 40 minutes. Office blood pressure (BP) was taken every 10 minutes until completing 60 minutes after the experimental session. The ambulatory BP device was programmed to take the readings every 20 minutes (awake time) and every 30 minutes (sleep time) over the course of 24 hours of monitoring. Statistical significance was defined as p < 0.05. RESULTS: Unlike the other experimental groups, there were no "non-responders" in the exercise/citrulline (EC) for "awake" (systolic and diastolic BP) and "24 hours" (diastolic BP). The effect sizes were more consistent in the EC for systolic and diastolic ambulatorial BP response. The effects were "large" (> 0.8) for "awake", "asleep", and "24 hours" only in the EC for diastolic BP. CONCLUSION: CM supplementation can increase the post-exercise hypotensive effects in hypertensives. In addition, the prevalence of non-responders is lower when associated with aerobic exercise and CM supplementation.
Asunto(s)
Presión Sanguínea/efectos de los fármacos , Citrulina/análogos & derivados , Ejercicio Físico/fisiología , Hipertensión/fisiopatología , Malatos/farmacología , Hipotensión Posejercicio/fisiopatología , Vasodilatadores/farmacología , Adulto , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Antropometría , Arginina/metabolismo , Citrulina/farmacología , Método Doble Ciego , Prueba de Esfuerzo , Femenino , Humanos , Hipertensión/terapia , Masculino , Persona de Mediana Edad , Óxido Nítrico/metabolismo , Efecto Placebo , Valores de Referencia , Estadísticas no Paramétricas , Factores de Tiempo , Resultado del TratamientoRESUMEN
Farney, TM, Bliss, MV, Hearon, CM, and Salazar, DA. The effect of citrulline malate supplementation on muscle fatigue among healthy participants. J Strength Cond Res 33(9): 2464-2470, 2019-The focus of the investigation was to examine the effects of citrulline malate (CM) on muscular fatigue in healthy, recreationally trained participants. Twelve participants (men = 6 and women = 6) (24.1 ± 3.9 years) visited the laboratory on 3 separate days, all separated by 1 week. Each visit consisted of consuming 1 of 3 treatments: placebo, CM (8 g), and control in which no drink mixture was consumed. For each day of testing, participants consumed assigned treatment and performed 1 high-intensity exercise trial consisting of squats, lunge jumps, squat jumps, and lateral jumps. Participants performed the exercises in the listed order, which was designated as 1 round. Each participant performed 3 rounds, with the work-to-rest ratio being 20 seconds of work and 30 seconds of rest. A 1-minute rest was given between rounds. A pre/post-exercise isokinetic leg extension test was performed to measure for peak power, peak torque, and rate of fatigue. In addition, blood lactate was obtained pre/post-exercise. There were no treatment or interaction effects (p > 0.05) for peak torque, peak power, rate of fatigue, or blood lactate accumulation. However, there was a statistical significant decrease from pre/post-exercise for peak torque (p = 0.003), peak power (p = 0.003), and rate of fatigue (p = 0.001). In addition, lactate accumulation did increase significantly from pre/post-exercise (p = 0.0001). Finally, neither total work nor final heart rate was statistically significant between the treatments (p > 0.05). Citrulline malate was not effective in improving performance or alleviating fatigue after a high-intensity exercise session.
Asunto(s)
Citrulina/análogos & derivados , Malatos/farmacología , Fatiga Muscular/efectos de los fármacos , Músculo Esquelético/efectos de los fármacos , Adulto , Citrulina/farmacología , Estudios Cruzados , Suplementos Dietéticos , Ejercicio Físico/fisiología , Prueba de Esfuerzo , Femenino , Voluntarios Sanos , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Ácido Láctico/sangre , Masculino , Fatiga Muscular/fisiología , Fuerza Muscular , Músculo Esquelético/fisiología , Método Simple Ciego , Torque , Adulto JovenRESUMEN
Organic acids play an important role in metal uptake and trafficking in plants. Therefore, the role of exogenous citrate and malate on Cd tolerance was studied in the seedlings of Oryza sativa L. cv MTU 7029. Seedlings were exposed to Cd plus organic acids in hydroponics and monitored changes in Cd accumulation, expression of metal transporters, chlorophyll fluorescence, and antioxidants. It found that organic acid supplements decrease Cd accumulation in leaf because of up-regulation of tonoplast localized heavy metal ATPase (OsHMA3) which allows vacuolar sequestration of Cd in the root. Malic acid helped Cd exclusion in the root too. A shift in Cd speciation from sulphhydryl to the carboxylic group also noticed in the roots of plants exposed to organic acids. Treatment of organic acids was effective to prevent Cd inducible Fe deficiency via up-regulation of the iron-regulated transporter (OsIRT1), increase in ferric chelate reductase activity, and formation of Cd stabilized Fe3+ - organic acid complex respectively. Also, exposure to organic acids increased the accumulation of antioxidants such as anthocyanin and glutathione (GSH) under Cd stress. Above changes assisted in upholding of photosynthetic electron transport and biomass productivity during the course of Cd treatment with organic acid supplements.
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Cadmio/metabolismo , Ácido Cítrico/farmacología , Hierro/metabolismo , Malatos/farmacología , Oryza/efectos de los fármacos , Oryza/metabolismo , Antioxidantes/metabolismo , Transporte Biológico , Biomasa , Cadmio/toxicidad , Proteínas de Transporte de Catión/metabolismo , FMN Reductasa/metabolismo , Oryza/crecimiento & desarrollo , Oxidación-Reducción , Estrés Oxidativo , Fotosíntesis , Plantones/efectos de los fármacos , Plantones/metabolismoRESUMEN
BACKGROUND: Use of supplements to aid performance is common practice amongst recreationally active individuals, including those without a sufficient evidence base. This investigation sought to assess whether acute supplementation with 8 g of citrulline malate (CM) (1.11: 1 ratio) would improve anaerobic performance. METHODS: A randomised double blind placebo control trial was employed, using a counterbalanced design. We recruited recreationally active men and women to take part in an isokinetic chair protocol, based on German Volume Training (GVT) whereby participants attempted to perform 10 sets of 10 repetitions against a force representing 70% of their peak concentric force. RESULTS: The number of repetitions achieved over the course of the GVT was 94.0 ± 7.9 and 90.9 ± 13.9 for placebo and CM respectively. There was no significant difference between the placebo and CM treatment for number of repetitions (P = 0.33), isometric (P = 0.60), concentric (P = 0.38), or eccentric (P = 0.65) peak force following the GVT. Total muscle soreness was significantly higher in the CM compared to the placebo treatment following the GVT protocol over 72 h (P = 0.01); although this was not accompanied by a greater workload/number of repetitions in the CM group. CONCLUSIONS: We conclude that an acute dose of CM does not significantly affect anaerobic performance using an isokinetic chair in recreational active participants. Practical implications include precaution in recommending CM supplementation. Coaches and athletes should be aware of the disparity between the chemical analyses of the products reviewed in the present investigation versus the manufacturers' claims.
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Citrulina/análogos & derivados , Suplementos Dietéticos , Malatos/farmacología , Músculo Esquelético/efectos de los fármacos , Mialgia/tratamiento farmacológico , Adulto , Citrulina/farmacología , Estudios Cruzados , Método Doble Ciego , Femenino , Humanos , Ácido Láctico/sangre , Masculino , Fuerza Muscular , Dinamómetro de Fuerza Muscular , Músculo Esquelético/fisiología , Adulto JovenRESUMEN
Gonzalez, AM, Spitz, RW, Ghigiarelli, JJ, Sell, KM, and Mangine, GT. Acute effect of citrulline malate supplementation on upper-body resistance exercise performance in recreationally resistance-trained men. J Strength Cond Res 32(11): 3088-3094, 2018-To investigate the effect of citrulline malate (CM) supplementation on upper-body resistance exercise performance, 12 recreationally resistance-trained men (21.4 ± 1.6 years; 163.0 ± 46.2 cm; 85.0 ± 12.4 kg) underwent 2 testing sessions administered in a randomized, double-blind fashion. During each visit, participants were provided either 8 g of CM or a placebo (PL) 40 minutes before beginning a standardized warm-up and initiating a barbell bench press resistance exercise protocol consisting of 5 sets of 15 repetitions at 75% 1 repetition maximum with 2-minute rest intervals. Participants were instructed to complete as many repetitions as possible until either reaching 15 repetitions or muscular failure. Total number of repetitions performed and power output were recorded for each set. Subjective measures of energy, focus, fatigue, and perceived exertion, along with muscle thickness of the triceps brachii, were assessed before and after exercise. Significant (p ≤ 0.05) main effects for time were observed for all variables except for subjective feelings of energy (p = 0.085). A group × time interaction (F = 2.86, p = 0.034, n = 0.21) was observed for repetitions performed, where participants performed more (p = 0.015) repetitions on set 3 during PL (5.7 ± 1.2 repetitions) compared with CM (4.6 ± 1.2 repetitions). However, during set 4, participants tended (p = 0.089) to perform more repetitions during CM (4.8 ± 1.8 repetitions) compared with PL (4.3 ± 1.3 repetitions). No other differences were observed between trials. Supplementation with 8 g of CM 40 minutes before the barbell bench press resistance exercise protocol did not increase exercise performance, augment the muscle swelling response to training, or alter subjective measures of focus, energy, and fatigue in recreationally resistance-trained men.
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Rendimiento Atlético/fisiología , Citrulina/análogos & derivados , Suplementos Dietéticos , Malatos/farmacología , Entrenamiento de Fuerza , Levantamiento de Peso/fisiología , Citrulina/farmacología , Estudios Cruzados , Método Doble Ciego , Fatiga , Humanos , Masculino , Músculo Esquelético/fisiología , Descanso , Adulto JovenRESUMEN
Two new malic acid derivatives, namely eucomic acid 1-methyl ester (2) and 6'''-acetylmilitaline (7), together with ten known compounds (1, 3-6, 8-12), were isolated from the dry tubers of Bletilla striata (Thunb.) Reichb. F., a perennial traditional Chinese medicinal herb, which was used for the treatment of pneumonophthisis, pneumonorrhagia, tuberculosis, and hemorrhage of the stomach or lung. Their structures were elucidated by spectroscopic analyses, including 1D-, 2D-NMR, and HR-ESI-MS.
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Medicamentos Herbarios Chinos/aislamiento & purificación , Malatos/aislamiento & purificación , Orchidaceae/química , Fenoles/aislamiento & purificación , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología , Malatos/química , Malatos/farmacología , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Fenoles/química , Fenoles/farmacología , Tubérculos de la Planta/químicaRESUMEN
Two local hydrogen-evolving strains of purple nonsulfur bacteria have been isolated, characterized, and identified as Rhodopseudomonas sp. TUT (strains Rh1 and Rh2). Lactate followed by succinate and malate supported the highest amounts of H2 production, growth (O.D.660nm, proteins and bacteriochlorphyll contents), nitrogenase activity, and uptake hydrogenase; the least of which was acetate. Alginate-immobilized cells evolved higher hydrogen amounts than free cell counterparts. Rh1 was more productive than Rh2 at all circumstances. Lactate-dependent hydrogen evolution was more than twice that of acetate, due to ATP productivity (2/-1, respectively), which is limiting to the nitrogenase activity. The preference of lactate over other acids indicates the feasibility of using these two strains in hydrogen production from dairy wastewater.
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Ácido Acético/farmacología , Células Inmovilizadas/efectos de los fármacos , Metabolismo Energético , Hidrógeno/metabolismo , Ácido Láctico/farmacología , Rhodopseudomonas/efectos de los fármacos , Ácido Acético/metabolismo , Adenosina Trifosfato/metabolismo , Alginatos/química , Bacterioclorofilas/biosíntesis , Células Inmovilizadas/metabolismo , Ácido Glucurónico/química , Ácidos Hexurónicos/química , Hidrogenasas/biosíntesis , Cinética , Ácido Láctico/metabolismo , Malatos/metabolismo , Malatos/farmacología , Nitrogenasa/biosíntesis , Fotosíntesis/fisiología , Rhodopseudomonas/metabolismo , Ácido Succínico/metabolismo , Ácido Succínico/farmacologíaRESUMEN
The aim of this study was to assess the effects of malate salts and culture on growth performance, carcass quality, ruminal fermentation products, and blood metabolites in heifers raised under southern Europe practical farm conditions. A total of 108 Charolaise cross heifers (214 ± 27.3 kg BW and 6.4 ± 1.1 mo of age) were housed in 18 pens of 6 animals each and used in a 114-d feedlot study. There was a totally randomized experimental design, and 6 pens were assigned to each of the following experimental diets: a control (no supplementation), the control plus 4 g of disodium/calcium malate mixture per kilogram of concentrate (2.12 g malate/kg), and the control plus 0.15 g of CBS 493.94 per kilogram of concentrate (1.5 × 10 cfu/kg). The control diet consisted of wheat-barley-based pelleted concentrate (32% starch, DM basis) and full-length barley straw. Concentrate and straw were fed separately ad libitum (5% orts) in an 88:12 ratio. On Days 0, 56, and 114, ruminal fluid and blood samples were obtained from each heifer between 2 and 2.5 h after the morning feeding by ruminocentesis and tail venipuncture, respectively. Body weight, concentrate ADFI, and G:F were recorded at 28, 56, 84, and 114 d. At slaughter, hot carcass weight and yield and carcass classification were determined in 2 representative heifers per pen (12 animals per dietary treatment). Supplementation with malate salts or did not affect concentrate ADFI ( = 0.98), ADG ( = 0.74), or G:F ( = 0.50) at any time during the experiment. At slaughter, there were no differences in carcass weight ( = 0.86), classification ( = 0.18), or carcass yield ( = 0.84) among experimental groups. Also, there were no differences treatments on ruminal pH ( = 0.24), ruminal fermentation products ( = 0.69, = 0.88, and = 0.93 for total VFA, NH-N, and lactate, respectively), and blood metabolites ( = 0.96, = 0.82, and = 0.15 for glucose, urea N, and lactate, respectively). In conclusion, under the feeding and management conditions of this study, diet supplementation with malate salts or did not have any significant effects on growth performance, carcass quality, ruminal fermentation products, and blood metabolites.