A Study of CAP-1002 in Ambulatory and Non-Ambulatory Patients With Duchenne Muscular Dystrophy
Muscular DystrophiesMuscular Dystrophy10 moreHOPE-2 is a double-blind clinical trial evaluating the safety and efficacy of a cell therapy called CAP-1002 in study participants with Duchenne muscular dystrophy (DMD). Non-ambulatory and ambulatory boys and young men who meet eligibility criteria will be randomly assigned to receive either CAP-1002 or placebo every 3 months for a total of 4 doses during a 12-month period.
Absorption, Metabolism, Excretion and Absolute Bioavailability of EDG-5506 in Healthy Volunteers...
Healthy VolunteerMuscular Dystrophies8 moreThis is a Phase 1 2-part, single-center, open-label study in healthy male volunteers. Part A will assess the absorption, metabolism, excretion, and pharmacokinetics of one oral dose of radiolabeled EDG-5506. Part B will assess bioavailability of EDG-5506 with a single oral dose of EDG-5506 and a single intravenous dose of radiolabeled EDG-5506.
The Efficacy of Protein Supplementation on Attenuating Muscle Atrophy Following Disuse in the Collegiate...
Disuse AtrophyFollowing orthopedic surgery and/or injury, a significant loss of muscle mass is generally observed. While this loss of muscle mass appears to be the norm, it causes significant problems in both the athletic and general population. Athletes struggle to regain their performance because of the decrease in muscle mass and also have a greater potential for reinjury while they are in a depleted state. In the general population, and particularly among the elderly, this loss in muscle mass can be even more devastating because as people age, it is more difficult to regain muscle after it is lost. In elderly individuals, this loss in muscle mass can lead to significant disability, diminished quality of life along with an increased risk of falls. In addition to the muscle mass lost during the post-operative period, the strength of the muscle also decreases. This has obvious performance implications in athletes, as well as having the potential to extend recovery time. In the elderly, decreased strength may result in reduced independence and inability to perform activities of daily living. Many previous bed rest studies have reported that significant bone loss also occurs during times of decreased mechanical loading. The post-operative period generally results in decreased mechanical loading; however, some muscle loading will still occur during the rehabilitation process. The dynamic relation between muscle activity/loading and bone density changes in the post-operative state has not been fully described and requires further study. With this knowledge of the importance of nutrition to the musculoskeletal system, applying the principles of increased protein intake through the addition of a dietary supplement to a population preparing for orthopedic surgery and subsequent muscle disuse is a logical next step. The investigators hypothesize that through the consumption of a protein-based dietary supplement three times per day (75g protein), along with educating patients on the importance of consuming foods that are high in protein, there will be an attenuation of decreases in muscle mass and strength as well as losses in bone that occur with orthopedic injury and disuse. The investigators long-term goal is to identify a nutritional protocol that can be implemented prior to and following orthopedic surgery to diminish the deleterious effects of the subsequent disuse on muscle and bone.
Effects of Kneehab 12-week Peri-operative Total Knee Arthroplasty
Knee OsteoarthritisDisuse AtrophyDetermine the efficacy of neuromuscular electrical stimulation (NMES, Kneehab) in promoting accelerated recovery of quadriceps function in patients recovering from total knee arthroplasty (TKA) as measured by increases in isometric strength of the knee extensors and scores in the Timed Up and Go (TUG) test.
Leucine Supplementation and Skeletal Muscle Disuse
Disuse AtrophyLeucine supplementation is widely known for promoting strong influence on skeletal muscle remodeling. This study aims to evaluate the effect of leucine supplementation on disuse-induced skeletal muscle atrophy.
The Regulation of Human Skeletal Muscle Mass by Contractile Perturbation
Muscle AtrophyDisuse Atrophy (Muscle) of Lower LegIt is well known that periods of weight training lead to increases in skeletal muscle size and strength. In contrast, periods of inactivity such as bed rest or immobilization result in losses of skeletal muscle size and strength. However, individuals experience variable magnitudes of muscle size change in response to changes in mechanical tension, such that certain individuals experience large changes in muscle mass whereas others do not. What is not currently known, and will be the primary goal of the present investigation, is to determine whether individuals who gain the most muscle mass with exercise training also lose the most muscle when they are immobilized. The investigators hypothesize that individuals who gain the most muscle with training will also lose the most with immobilization.
Immobilization and Protein Supplementation (IM-PRO)
Disuse AtrophyAgingIn the present study, the effects of 5 days of lower limb immobilization with or without twice-daily protein supplementation on muscle mass and muscle fiber characteristics will be determined. A young group will be included to compare the changes in muscle mass and muscle fiber characteristics between young and old men.
Electrical Stimulation During Immobilization
Disuse AtrophyImmobilization1 moreIn the present study, the effects of 5 days of lower limb immobilization with or without daily neuromuscular electrical stimulation on muscle mass and muscle fiber characteristics will be determined.
Can Supplemental Leucine Offset Disuse-induced Muscle Atrophy?
Muscle Disuse AtrophyAgeing is associated with a gradual decline in muscle mass that is detrimental to both physical function and metabolic health, increasing the risk of morbidity and mortality. The loss of protein muscle mass with ageing is poorly understood, but it may partly relate to inactivity/disuse (i.e. during injury or hospitalization). Periods of inactivity/disuse blunt the ability of muscle to grow (termed anabolic blunting), leading to a loss of muscle mass and strength. An accumulation of these periods over a lifetime promotes the devastating loss of muscle protein mass and strength seen with ageing. Disuse-induced muscle loss is underpinned by a blunted muscle anabolic response to protein nutrition. Supplementing the diet with the amino acid leucine may offer a potential solution to alleviate muscle mass and strength loss during disuse. In fact, leucine is suggested to promote muscle protein growth and reduce muscle protein loss during disuse in rats, but this is yet to be shown in humans. Accordingly, the proposed study will investigate whether leucine supplementation can offset muscle and strength loss during short-term disuse. Twenty-four healthy (non-obese, non-diabetic, non-smokers) men aged 18-35 years will initially complete a lower-limb strength assessment and undergo a body composition scan three days later. The following morning, participants will be randomly assigned to ingest either 5g of leucine (n=12) or a caloric-matched placebo (n=12) with each meal over a 7 d period of a single-leg immobilisation. Immediately following immobilisation participants will undergo another body composition scan. Additionally, a stable isotope infusion will be combined with serial muscle biopsies from the thigh of each leg to determine the measure rates of muscle protein synthesis in the fasted state and in the 'early' and 'late' phase of feeding. A day later, the assessment of muscle strength will be repeated.
Preventing Bed-rest Induced Muscle Loss in the Elderly
Muscle LossDisuse Atrophy3 moreEpisodes of inactivity due to hospitalisation, as short as 5 days, are associated with rapid muscle and strength loss in the elderly. The observed muscle loss with inactivity is likely due to muscle anabolic resistance and increased breakdown rates of muscle tissue. This is of great concern as the average hospital stay in the elderly is 5-6 days. Moreover, minor illnesses not requiring hospitalisation generally require short-term periods of inactive home-based recovery. The accumulation of repeated disuse events in older individuals manifests in a chronic muscle anabolic resistance (i.e. the inability of muscle to respond to anabolic stimuli such as exercise and nutrition) that may underpin the slow but devastating process of age-related muscle loss. It is our belief that strategies to promote muscle health in ageing and reduce healthcare expenditure, should focus on alleviating muscle deterioration and anabolic resistance during short-term disuse. In this regard, we propose that resistance exercise (i.e. weight lifting) performed prior to a disuse event (termed 'prehabilitation') may be sufficient to offset muscle loss in older individuals. Thus, we suggest the potent effect of resistance exercise in older muscles may prevent muscle loss during short-term disuse.