Sarcopenia and recovery from Disuse-Induced Atrophy

肌肉减少症和废用性萎缩的恢复

• 批准号: 10549727
• 负责人: Sue C Bodine
• 金额: --
• 依托单位: OKLAHOMA CITY VA MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-01-01 至 2025-12-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10549727
• 关键词: Acceleration; Acute; Address; Age; Age Months; Aging; Animal Model; Animals; Atrophic; Attenuated; Bed rest; Clinical; Cues; Data; Denervation; Development; Diet; Dietary Supplementation; Disuse Atrophy; Dose; Elderly; Euthanasia; Event; Female; Fish Oils; Gene Expression; Genetic Transcription; Goals; Growth; Hindlimb Suspension; Human; Hybrids; Immobilization; Impairment; Individual; Injury; Length of Stay; Life Style; Limb structure; Medical; Modeling; Molecular; Monitor; Motor; Muscle; Muscle Fibers; Muscle function; Muscular Atrophy; Nerve; Neuromuscular Junction; Norway; Older Population; Omega-3 Fatty Acids; Output; Pathway interactions; Patients; Persons; Pharmacologic Substance; Process; Rattus; Recovery; Recovery of Function; Rehabilitation therapy; Research; Rodent; Skeletal Muscle; Supplementation; System; Testing; Time; Trauma; Traumatic injury; United States Department of Veterans Affairs; Veterans; Weight-Bearing state; age-related muscle loss; aged; aging population; cohort; dietary; disability; effective therapy; effectiveness testing; falls; fatty acid supplementation; frailty; functional loss; impaired capacity; improved; insight; male; mechanical load; middle age; muscle form; muscle strength; neural; prevent; programs; resistance exercise; sarcopenia; skeletal muscle wasting; therapeutically effective; translational applications

The aging process is associated with a progressive decline in motor function that has a major impact on the ability to maintain an independent lifestyle; contributing to the frailty and loss of mobility observed in older adults. Aging is also associated with a reduced capacity to respond to growth cues derived from activities such as resistance exercise and return to weight bearing following inactivity or injury. An inability to respond to mechanical loading or to restore muscle size following extended periods of bed rest or inactivity accelerates the progression of sarcopenia and contributes to the loss of functional mobility, independence and the onset of frailty. The proposed research is of particular relevance to the Veteran’s Administration since a significant number of patients within the system will suffer skeletal muscle atrophy as a consequence of bed rest, immobilization, or neural trauma. Further, the effects of muscle atrophy are more debilitating with age resulting in longer hospital stays, a decrease in mobility and independence, an increase in falls, and long-term disability. Since the population of older veterans is rising, this issue represents a growing medical and monetary concern for the VA. Thus, the long-term objective of the research outlined in this proposal is to address an important unmet clinical need through the development of effective therapies for the enhancement of muscle recovery following atrophy. Based on our recent findings, we hypothesize that the lack of functional recovery following disuse-induced atrophy in aged animals is related, in part, to an increase in neuromuscular junction impairment during disuse that worsens upon reloading. Recent studies suggest that diet supplementation with long-chain omega-3 fatty acids has benefits to muscle mass and force output, however, further study is needed. It is the objective of this proposal to test the ability of dietary supplementation with fish oil to prevent the loss of muscle mass and function with age and enhance the recovery of muscle mass and function following disuse-induced atrophy. These studies will use an animal model that has outstanding translational application to humans: the Fischer Brown Norway F1 hybrid rat (FBNF1). Completion of the specific aims outlined in this proposal will provide data on whether fish oil is a potential treatment for sarcopenia and/or can enhance the recovery of muscle mass and function from disuse atrophy. The studies will also provide information on the mechanisms involved in sarcopenia and age-associated loss of growth capacity. In specific aim 1 we will test the ability of fish oil supplementation to enhance the recovery of muscle from atrophy induced by hindlimb unloading in old male FBNF1 rats. Old rats will receive an 8-week loading dose of dietary fish oil supplementation prior to hindlimb unloading, which will continue throughout the 14 days of unloading and 14 days of reloading. In specific aim 2 we will determine if 9 months of dietary fish oil supplementation can prevent or attenuate the loss of muscle mass and strength in male and female rats. Dietary supplementation will begin at 22 months of age in males and 20 months of age in females; ages at which significant loss of hind limb muscle mass and function are not measurable. Rats will be euthanized at multiple time points between 22 and 31 months in males (20 to 29 months in females) to monitor the loss of muscle mass and strength and to examine potential molecular and cellular mechanisms of sarcopenia and potential mechanisms of action of the fish oil treatment.

衰老过程与运动功能的逐渐下降有关，这对身体产生重大影响。 保持独立生活方式的能力；导致老年人虚弱和行动不便 成年人。衰老还与对活动产生的生长线索做出反应的能力下降有关 例如抵抗运动以及在不活动或受伤后恢复负重。无法回应 机械负荷或在长时间卧床休息或不活动后恢复肌肉大小 加速肌肉减少症的进展并导致功能活动能力和独立性的丧失 以及虚弱的开始。拟议的研究与退伍军人管理局特别相关 因为系统内的大量患者将遭受骨骼肌萎缩的困扰 卧床休息、固定或神经损伤的后果。此外，肌肉萎缩的影响更大 随着年龄的增长而衰弱，导致住院时间延长、活动能力和独立性下降、 跌倒和长期残疾。由于老年退伍军人的数量不断增加，这个问题代表了一个 对退伍军人管理局日益增长的医疗和财务担忧。因此，该研究的长期目标概述于 该提案旨在通过开发有效的疗法来解决重要的未满足的临床需求 用于增强萎缩后的肌肉恢复。根据我们最近的发现，我们假设 老年动物废用性萎缩后缺乏功能恢复部分与 废弃期间神经肌肉接头损伤增加，重新加载时会恶化。最近的研究 表明饮食中补充长链 omega-3 脂肪酸对肌肉质量和 然而，力量输出还需要进一步研究。该提案的目的是测试饮食的能力 补充鱼油可防止肌肉质量和功能随着年龄的增长而损失，并增强 废用性萎缩后肌肉质量和功能的恢复。这些研究将使用动物 对人类具有杰出转化应用的模型：Fischer Brown 挪威 F1 杂交大鼠 （FBNF1）。完成本提案中概述的具体目标将提供有关鱼油是否是一种 肌肉减少症的潜在治疗方法和/或可以增强肌肉质量和功能的恢复 废用性萎缩。这些研究还将提供有关肌肉减少症和肌肉减少症所涉及机制的信息。 与年龄相关的生长能力丧失。在具体目标 1 中，我们将测试补充鱼油的能力 增强老年雄性 FBNF1 大鼠后肢卸荷引起的肌肉萎缩的恢复。老的 大鼠在后肢卸载前将接受为期 8 周的负荷剂量膳食鱼油补充剂， 这将持续整个卸货的 14 天和装货的 14 天。在具体目标 2 中，我们将 确定 9 个月的膳食鱼油补充剂是否可以预防或减轻肌肉质量的损失 以及雄性和雌性大鼠的力量。男性和女性从 22 个月大时开始膳食补充剂 女性20个月大；后肢肌肉质量和功能未显着丧失的年龄 可测量的。雄性大鼠将在 22 至 31 个月（20 至 29 个月）之间的多个时间点被安乐死。 女性几个月）监测肌肉质量和力量的损失，并检查潜在的分子和 肌肉减少症的细胞机制和鱼油治疗的潜在作用机制。