View clinical trials related to Muscular Disorders, Atrophic.
Filter by:The purpose of the proposed research is to define whether there are differences between females and males (i.e. sex-based differences) in the metabolic and mechanistic regulation of disuse-induced muscle atrophy in vivo in humans.
HOPE-3 is a two cohort, Phase 3, multi-center, randomized, double-blind, placebo-controlled clinical trial evaluating the efficacy and safety of a cell therapy called CAP-1002 in study participants with Duchenne muscular dystrophy (DMD) and impaired skeletal muscle function. 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 the first 12-months of the study. All participants will be eligible to receive 4 doses of CAP-1002 for an additional 12 months as part of an open-label extended assessment period.
This project aims to determine whether a novel strength training rehabilitation protocol can diminish the negative consequences of limb immobilization and expedite the restoration of muscle function during retraining in healthy individuals.
Following injury or surgery to a limb, it is often immobilised to allow tissue healing. Short periods of disuse cause loss of muscle size and strength and impaired mechanical properties of tendons, which leads to reduced function. Strategies to combat these deconditioning adaptations include neuromuscular electrical stimulation (NMES), however at present its effectiveness is limited. Recent research suggests that the effects of NMES can be augmented with blood flow restriction (BFR). At present, the effect of combining these two techniques on muscle function during limb immobilisation is unknown. Furthermore, the impact of BFR training during retraining following immobilisation is unknown.
Skeletal muscle plays several different roles in the promotion and maintenance of health and well-being. The loss of muscle mass that occurs with aging, chronic muscle wasting diseases, and physical inactivity puts people at an increased risk of frailty and becoming insulin resistant, and therefore imposes a significant burden on health care spending. Resistance exercise participation has proven particularly effective for increasing muscle mass and strength. This effectiveness can be used by health care practitioners in a rehabilitation setting to promote the recovery of individuals who have undergone involuntary periods of muscular unloading (i.e. limb immobilization caused by a sports injury or reconstructive surgery). However, there is large variability in the amount of muscle mass and strength that people gain following participation in resistance exercise. Some individuals fail to increase the size of their muscle (low responders) whereas others show vary large increases in muscle size (high responders) in response to the same resistance training program. People also show differences in the amount of muscle tissue they lose when they have a limb immobilized. To circumvent variability across individuals, the investigators utilized a within-person paired Hypertrophy and Atrophy ('HYPAT') strategy that reduced response heterogeneity by ~40% (Available at: https://ssrn.com/abstract=3445673). Specifically, one leg performed resistance training for 10 weeks to induce hypertrophy, whereas the other leg underwent single-leg immobilization for 2 weeks to induce atrophy. The primary goal of the study will be to gain insight into the molecular responses to an acute period of single-leg immobilization and resistance exercise (8 days). The investigators will use an integrated systems biology approach to monitor the individual rates of over one hundred different muscle proteins.
Episodes 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.
Loss of muscle can be caused by a variety of stimuli and results in reduced mobility and strength and also impacts whole body health. Whilst it is known that muscles waste the process by which this occurs is not well understood. Furthermore, whilst some muscles waste quickly others seem resistant to the effects of disuse. This study aims to evaluate how quickly changes in muscles start to occur, and investigate the processes which underlie muscle atrophy. By studying muscles which waste quickly and those which are resistant to atrophy this study aims to identify the different processes which lead to muscle loss. This study will also evaluate the differences in muscle changes between young and old people.
This study will examine the influence of n3 PUFA supplementation on the rate of muscle atrophy in older women undergoing 1 week of unilateral limb immobilization. Assessments in skeletal muscle strength and skeletal muscle volume will also me made before, after and in recovery from immobilization.
Ageing 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.
Limb injury generally requires a period of recovery during which time the limb is often immobilised (e.g. with a cast or brace) resulting in a rapid loss of skeletal muscle. Despite the importance of muscle loss during injury, our understanding of how it occurs is incomplete. Several factors are likely to contribute, including a lack of muscle contraction and injury induced inflammation. In this study, the investigators will recruit healthy volunteers who will spend 7 days in a knee brace to replicate leg immobilisation. Prior to immobilisation, half of the participants will perform a single session of strenuous resistance exercise which is known to cause muscle damage and initiate an inflammatory response. This is designed to replicate the muscle damage and inflammation that occurs with injury. The remaining half of participants will not perform this exercise, allowing us to look at the additive effect of muscle damage and inflammation on muscle loss with immobilisation.