RESUMO
Amyotrophic lateral sclerosis (ALS) is a progressive disease of neuronal degeneration in the motor cortex, brainstem, and spinal cord, resulting in impaired motor function and premature demise as a result of insufficient respiratory drive. ALS is associated with dysfunctions in neurons, neuroglia, muscle cells, energy metabolism, and glutamate balance. Currently, there is not a widely accepted, effective treatment for this condition. Prior work from our lab has demonstrated the efficacy of supplemental nutrition with the Deanna Protocol (DP). In the present study, we tested the effects of three different treatments in a mouse model of ALS. These treatments were the DP alone, a glutamate scavenging protocol (GSP) alone, and a combination of the two treatments. Outcome measures included body weight, food intake, behavioral assessments, neurological score, and lifespan. Compared to the control group, DP had a significantly slower decline in neurological score, strength, endurance, and coordination, with a trend toward increased lifespan despite a greater loss of weight. GSP had a significantly slower decline in neurological score, strength, endurance, and coordination, with a trend toward increased lifespan. DP+GSP had a significantly slower decline in neurological score with a trend toward increased lifespan, despite a greater loss of weight. While each of the treatment groups fared better than the control group, the combination of the DP+GSP was not better than either of the individual treatments. We conclude that the beneficial effects of the DP and the GSP in this ALS mouse model are distinct, and appear to offer no additional benefit when combined.
Assuntos
Esclerose Lateral Amiotrófica , Camundongos , Animais , Esclerose Lateral Amiotrófica/metabolismo , Superóxido Dismutase-1/metabolismo , Ácido Glutâmico/metabolismo , Camundongos Transgênicos , Modelos Animais de Doenças , Superóxido Dismutase/metabolismoRESUMO
The ketone bodies acetoacetate (AcAc) and ß-hydroxybutyrate (ßHB) have pleiotropic effects in multiple organs including brain, heart, and skeletal muscle by serving as an alternative substrate for energy provision, and by modulating inflammation, oxidative stress, catabolic processes, and gene expression. Of particular relevance to athletes are the metabolic actions of ketone bodies to alter substrate utilisation through attenuating glucose utilisation in peripheral tissues, anti-lipolytic effects on adipose tissue, and attenuation of proteolysis in skeletal muscle. There has been long-standing interest in the development of ingestible forms of ketone bodies that has recently resulted in the commercial availability of exogenous ketone supplements (EKS). These supplements in the form of ketone salts and ketone esters, in addition to ketogenic compounds such as 1,3-butanediol and medium chain triglycerides, facilitate an acute transient increase in circulating AcAc and ßHB concentrations, which has been termed 'acute nutritional ketosis' or 'intermittent exogenous ketosis'. Some studies have suggested beneficial effects of EKS to endurance performance, recovery, and overreaching, although many studies have failed to observe benefits of acute nutritional ketosis on performance or recovery. The present review explores the rationale and historical development of EKS, the mechanistic basis for their proposed effects, both positive and negative, and evidence to date for their effects on exercise performance and recovery outcomes before concluding with a discussion of methodological considerations and future directions in this field.
Assuntos
Cetonas , Cetose , Humanos , Corpos Cetônicos/metabolismo , Acetoacetatos , Ácido 3-Hidroxibutírico , Suplementos NutricionaisRESUMO
BACKGROUND: Interest into the health, disease, and performance impact of exogenous ketone bodies has rapidly expanded due to their multifaceted physiological and signaling properties but limiting our understanding is the isolated analyses of individual types and dose/dosing protocols. METHODS: Thirteen recreational male distance runners (24.8 ± 9.6 years, 72.5 ± 8.3 kg, VO2max 60.1 ± 5.4 ml/kg/min) participated in this randomized, double-blind, crossover design study. The first two sessions consisted of a 5-km running time trial familiarization and a VO2max test. During subsequent trials, subjects were randomly assigned to one (KS1: 22.1 g) or two (KS2: 44.2 g) doses of beta-hydroxybutyrate (ßHB) and medium chain triglycerides (MCTs) or flavor matched placebo (PLA). Blood R-ßHB, glucose, and lactate concentrations were measured at baseline (0-min), post-supplement (30 and 60 min), post-exercise (+ 0 min, + 15 min). Time, heart rate (HR), rating of perceived exertion (RPE), affect, respiratory exchange ratio, oxygen consumption (VO2), carbon dioxide production, and ventilation were measured during exercise. Cognitive performance was evaluated prior to and post-exercise. RESULTS: KS significantly increased R-ßHB, with more potent and prolonged elevations in KS2, illustrating an administrative and dosing effect. R-ßHB was significantly decreased in KS1 compared to KS2 illustrating a dosing and exercise interaction effect. Blood glucose elevated post-exercise but was unchanged across groups. Blood lactate significantly increased post-exercise but was augmented by KS administration. Gaseous exchange, respiration, HR, affect, RPE, and exercise performance was unaltered with KS administration. However, clear responders and none-responders were indicated. KS2 significantly augmented cognitive function in pre-exercise conditions, while exercise increased cognitive performance for KS1 and PLA to pre-exercise KS2 levels. CONCLUSION: Novel ßHB + MCT formulation had a dosing effect on R-ßHB and cognitive performance, an administrative response on blood lactate, while not influencing gaseous exchange, respiration, HR, affect, RPE, and exercise performance.
RESUMO
Nutritional ketosis has been proven effective for neurometabolic conditions and disorders linked to metabolic dysregulation. While inducing nutritional ketosis, ketogenic diet (KD) can improve motor performance in the context of certain disease states, but it is unknown whether exogenous ketone supplements-alternatives to KDs-may have similar effects. Therefore, we investigated the effect of ketone supplements on motor performance, using accelerating rotarod test and on postexercise blood glucose and R-beta-hydroxybutyrate (R-ßHB) levels in rodent models with and without pathology. The effect of KD, butanediol (BD), ketone-ester (KE), ketone-salt (KS), and their combination (KE + KS: KEKS) or mixtures with medium chain triglyceride (MCT) (KE + MCT: KEMCT; KS + MCT: KSMCT) was tested in Sprague-Dawley (SPD) and WAG/Rij (WR) rats and in GLUT-1 Deficiency Syndrome (G1D) mice. Motor performance was enhanced by KEMCT acutely, KE and KS subchronically in SPD rats, by KEKS and KEMCT groups in WR rats, and by KE chronically in G1D mice. We demonstrated that exogenous ketone supplementation improved motor performance to various degrees in rodent models, while effectively elevated R-ßHB and in some cases offsets postexercise blood glucose elevations. Our results suggest that improvement of motor performance varies depending on the strain of rodents, specific ketone formulation, age, and exposure frequency.
Assuntos
Suplementos Nutricionais , Cetonas/administração & dosagem , Atividade Motora/efeitos dos fármacos , Ácido 3-Hidroxibutírico/sangue , Animais , Glicemia/análise , Butileno Glicóis/administração & dosagem , Butileno Glicóis/sangue , Erros Inatos do Metabolismo dos Carboidratos/metabolismo , Erros Inatos do Metabolismo dos Carboidratos/terapia , Dieta Cetogênica/métodos , Humanos , Cetose/sangue , Cetose/terapia , Masculino , Camundongos , Modelos Animais , Proteínas de Transporte de Monossacarídeos/deficiência , Proteínas de Transporte de Monossacarídeos/metabolismo , Ratos , Ratos Sprague-Dawley , Roedores , Teste de Desempenho do Rota-Rod/métodos , Triglicerídeos/sangueRESUMO
OBJECTIVE: The aim of this study was to examine the effects of a ketone ester (KE)-supplemented diet on energy expenditure (EE) and adiposity in mice housed at 23 °C versus thermoneutrality (30 °C), in which sympathetic nervous system activity is diminished. METHODS: Thirty-two 10-week-old male C57BL/6J mice were assigned to 1 of 4 groups (n = 8 per group): 30% KE diet + 23 °C (KE23), control (CON) diet + 23 °C (CON23), 30% KE diet + 30 °C (KE30), or CON diet + 30 °C (CON30). CON mice were pair-fed to the average intake of mice consuming the KE diet (ad libitum) for 8 weeks. Body composition and components of energy balance were measured at completion of the study. RESULTS: CON23 (mean ± SD, 26.0 ± 1.6 g) and CON30 (29.7 ± 1.4 g) mice weighed more than KE groups (P < 0.03 for both) and were also different from each other (CON23 vs. CON30, P < 0.01). However, KE23 (23.4 ± 2.7 g) and KE30 (23.1 ± 1.9 g) mice were not different in body weight. As expected, food intake at 30 °C (2.0 ± 0.3 g/d) was lower than at 23 °C (2.6 ± 0.3 g/d, P < 0.01). Diet did not influence resting and total EE, but mice housed at 30 °C had lower EE compared with mice at 23 °C (P < 0.01). CONCLUSIONS: Dietary KEs attenuate body weight gain at standard (23 °C) and thermoneutral (30 °C) housing temperatures, and this effect is not mediated by increased EE under these conditions.
Assuntos
Adiposidade/fisiologia , Peso Corporal/efeitos dos fármacos , Ésteres/metabolismo , Animais , Suplementos Nutricionais , Modelos Animais de Doenças , Metabolismo Energético , Masculino , CamundongosRESUMO
Athletes, clinicians, and practitioners are increasingly interested in the proposed performance and therapeutic benefits of nutritional ketosis (NK). NK is best operationally defined as a nutritionally induced metabolic state resulting in blood ß-hydroxybutyrate concentrations of ≥0.5 mM. Most tissues readily metabolize ketone bodies (KBs), and KBs in turn regulate metabolism and signaling in both a systemic and tissue-specific manner. During fasting, starvation, or ketogenic diets, endogenous synthesis of KBs is amplified resulting in a state of NK. Orally administered exogenous ketone supplements rapidly elevate circulating KBs and produce a similar, but far from identical, metabolic state. NK results in a number of convergent features regardless of endogenous or exogenous induction; however, important differences also are observed. The implications of NK across health, disease, and performance is rapidly becoming more evident, thus acknowledging the convergent and divergent features of NK is critical for fully understanding the potential utility of this metabolic state.
Assuntos
Desempenho Atlético/fisiologia , Dieta Cetogênica , Suplementos Nutricionais , Corpos Cetônicos/metabolismo , Cetose/metabolismo , HumanosRESUMO
Diseases involving inflammation and oxidative stress can be exacerbated by high blood glucose levels. Due to tight metabolic regulation, safely reducing blood glucose can prove difficult. The ketogenic diet (KD) reduces absolute glucose and insulin, while increasing fatty acid oxidation, ketogenesis, and circulating levels of ß-hydroxybutyrate (ßHB), acetoacetate (AcAc), and acetone. Compliance to KD can be difficult, so alternative therapies that help reduce glucose levels are needed. Exogenous ketones provide an alternative method to elevate blood ketone levels without strict dietary requirements. In this study, we tested the changes in blood glucose and ketone (ßHB) levels in response to acute, sub-chronic, and chronic administration of various ketogenic compounds in either a post-exercise or rested state. WAG/Rij (WR) rats, a rodent model of human absence epilepsy, GLUT1 deficiency syndrome mice (GLUT1D), and wild type Sprague Dawley rats (SPD) were assessed. Non-pathological animals were also assessed across different age ranges. Experimental groups included KD, standard diet (SD) supplemented with water (Control, C) or with exogenous ketones: 1, 3-butanediol (BD), ßHB mineral salt (KS), KS with medium chain triglyceride/MCT (KSMCT), BD acetoacetate diester (KE), KE with MCT (KEMCT), and KE with KS (KEKS). In rested WR rats, the KE, KS, KSMCT groups had lower blood glucose level after 1 h of treatment, and in KE and KSMCT groups after 24 h. After exercise, the KE, KSMCT, KEKS, and KEMCT groups had lowered glucose levels after 1 h, and in the KEKS and KEMCT groups after 7 days, compared to control. In GLUT1D mice without exercise, only KE resulted in significantly lower glucose levels at week 2 and week 6 during a 10 weeks long chronic feeding study. In 4-month and 1-year-old SPD rats in the post-exercise trials, blood glucose was significantly lower in KD and KE, and in KEMCT groups, respectively. After seven days, the KSMCT group had the most significantly reduced blood glucose levels, compared to control. These results indicate that exogenous ketones were efficacious in reducing blood glucose levels within and outside the context of exercise in various rodent models of different ages, with and without pathology.
Assuntos
Ácido 3-Hidroxibutírico/farmacologia , Acetoacetatos/farmacologia , Glicemia/efeitos dos fármacos , Butileno Glicóis/farmacologia , Erros Inatos do Metabolismo dos Carboidratos/terapia , Dieta Cetogênica , Suplementos Nutricionais , Epilepsia Tipo Ausência/terapia , Proteínas de Transporte de Monossacarídeos/deficiência , Animais , Biomarcadores , Glicemia/metabolismo , Erros Inatos do Metabolismo dos Carboidratos/sangue , Erros Inatos do Metabolismo dos Carboidratos/genética , Erros Inatos do Metabolismo dos Carboidratos/fisiopatologia , Modelos Animais de Doenças , Regulação para Baixo , Epilepsia Tipo Ausência/sangue , Epilepsia Tipo Ausência/genética , Epilepsia Tipo Ausência/fisiopatologia , Transportador de Glucose Tipo 1/deficiência , Transportador de Glucose Tipo 1/genética , Masculino , Camundongos Knockout , Proteínas de Transporte de Monossacarídeos/sangue , Proteínas de Transporte de Monossacarídeos/genética , Esforço Físico , Ratos Sprague-Dawley , Descanso , Fatores de TempoRESUMO
Central nervous system oxygen toxicity (CNS-OT) manifests as tonic-clonic seizures and is a limitation of hyperbaric oxygen therapy (HBOT), as well as of recreational and technical diving associated with elevated partial pressure of oxygen. A previous study showed that ketone ester (1,3-butanediol acetoacetate diester, KE) administration delayed latency to seizures (LS) in 3-month-old Sprague-Dawley (SD) rats. This study explores the effect of exogenous ketone supplements in additional dosages and formulations on CNS-OT seizures in 18 months old SD rats, an age group correlating to human middle age. Ketogenic agents were given orally 60 min prior to exposure to hyperbaric oxygen and included control (water), KE (10 g/kg), KE/2 (KE 5 g/kg + water 5 g/kg), KE + medium-chain triglycerides (KE 5 g/kg + MCT 5 g/kg), and ketone salt (Na+ /K+ ßHB, KS) + MCT (KS 5 g/kg + MCT 5 g/kg). Rats were exposed to 100% oxygen at 5 atmospheres absolute (ATA). Upon seizure presentation (tonic-clonic movements) experiments were immediately terminated and blood was tested for glucose and D-beta-hydroxybutyrate (D-ßHB) levels. While blood D-ßHB levels were significantly elevated post-dive in all treatment groups, LS was significantly delayed only in KE (P = 0.0003), KE/2 (P = 0.023), and KE + MCT (P = 0.028) groups. In these groups, the severity of seizures appeared to be reduced, although these changes were significant only in KE-treated animals (P = 0.015). Acetoacetate (AcAc) levels were also significantly elevated in KE-treated animals. The LS in 18-month-old rats was delayed by 179% in KE, 219% in KE + MCT, and 55% in KE/2 groups, while only by 29% in KS + MCT. In conclusion, KE supplementation given alone and in combination with MCT elevated both ßHB and AcAc, and delayed CNS-OT seizures.
Assuntos
Oxigenoterapia Hiperbárica/efeitos adversos , Cetonas/farmacologia , Convulsões/prevenção & controle , Animais , Sistema Nervoso Central/efeitos dos fármacos , Cetonas/administração & dosagem , Cetonas/uso terapêutico , Masculino , Oxigênio/toxicidade , Ratos , Ratos Sprague-Dawley , Tempo de Reação , Convulsões/etiologia , Convulsões/terapiaRESUMO
Gliomas are a highly heterogeneous tumor, refractory to treatment and the most frequently diagnosed primary brain tumor. Although the current WHO grading system (2016) demonstrates promise towards identifying novel treatment modalities and better prediction of prognosis over time, to date, existing targeted and mono therapy approaches have failed to elicit a robust impact on disease progression and patient survival. It is possible that tumor heterogeneity as well as specifically targeted agents fail because redundant molecular pathways in the tumor make it refractory to such approaches. Additionally, the underlying metabolic pathology, which is significantly altered during neoplastic transformation and tumor progression, is unaccounted for. With several molecular and metabolic pathways implicated in the carcinogenesis of CNS tumors, including glioma, we postulate that a systemic, broad spectrum approach to produce robust targeting of relevant and multiple molecular and metabolic regulation of growth and survival pathways, critical to the modulation of hallmarks of carcinogenesis, without clinically limiting toxicity, may provide a more sustained impact on clinical outcomes compared to the modalities of treatment evaluated to date. The objective of this review is to examine the emerging hallmark of reprogramming energy metabolism of the tumor cells and the tumor microenvironment during carcinogenesis, and to provide a rationale for exploiting this hallmark and its biological capabilities as a target for secondary chemoprevention and treatment of glioma. This review will primarily focus on interventions to induce ketosis to target the glycolytic phenotype of many cancers, with specific application to secondary chemoprevention of low grade glioma- to halt the progression of lower grade tumors to more aggressive subtypes, as evidenced by reduction in validated intermediate endpoints of disease progression including clinical symptoms.
Assuntos
Antineoplásicos/uso terapêutico , Metabolismo Energético/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Animais , Antineoplásicos/farmacologia , Transformação Celular Neoplásica , Dieta Cetogênica , Suplementos Nutricionais , Gerenciamento Clínico , Progressão da Doença , Glioma/tratamento farmacológico , Glioma/etiologia , Glioma/metabolismo , Glioma/patologia , Glucose/metabolismo , Glicólise , Humanos , Cetose , Terapia de Alvo Molecular , Neoplasias/etiologia , Neoplasias/patologia , Estresse Oxidativo , Resultado do TratamentoRESUMO
Nutritional ketosis has been proven effective for seizure disorders and other neurological disorders. The focus of this study was to determine the effects of ketone supplementation on anxiety-related behavior in Sprague-Dawley (SPD) and Wistar Albino Glaxo/Rijswijk (WAG/Rij) rats. We tested exogenous ketone supplements added to food and fed chronically for 83 days in SPD rats and administered sub-chronically for 7 days in both rat models by daily intragastric gavage bolus followed by assessment of anxiety measures on elevated plus maze (EPM). The groups included standard diet (SD) or SD + ketone supplementation. Low-dose ketone ester (LKE; 1,3-butanediol-acetoacetate diester, ~10 g/kg/day, LKE), high dose ketone ester (HKE; ~25 g/kg/day, HKE), beta-hydroxybutyrate-mineral salt (ßHB-S; ~25 g/kg/day, KS) and ßHB-S + medium chain triglyceride (MCT; ~25 g/kg/day, KSMCT) were used as ketone supplementation for chronic administration. To extend our results, exogenous ketone supplements were also tested sub-chronically on SPD rats (KE, KS and KSMCT; 5 g/kg/day) and on WAG/Rij rats (KE, KS and KSMCT; 2.5 g/kg/day). At the end of treatments behavioral data collection was conducted manually by a blinded observer and with a video-tracking system, after which blood ßHB and glucose levels were measured. Ketone supplementation reduced anxiety on EPM as measured by less entries to closed arms (sub-chronic KE and KS: SPD rats and KSMCT: WAG/Rij rats), more time spent in open arms (sub-chronic KE: SPD and KSMCT: WAG/Rij rats; chronic KSMCT: SPD rats), more distance traveled in open arms (chronic KS and KSMCT: SPD rats) and by delayed latency to entrance to closed arms (chronic KSMCT: SPD rats), when compared to control. Our data indicates that chronic and sub-chronic ketone supplementation not only elevated blood ßHB levels in both animal models, but reduced anxiety-related behavior. We conclude that ketone supplementation may represent a promising anxiolytic strategy through a novel means of inducing nutritional ketosis.