Accurate Quantification in Physiologic Phosphorus MR Spectroscopy

生理磷 MR 光谱的准确定量

• 批准号: 10688868
• 负责人: Richard Spencer
• 金额: $ 26.58万
• 依托单位: NATIONAL INSTITUTE ON AGING
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10688868
• 关键词: Aerobic; Aerobic Exercise; Age; Aging; Attenuated; Baltimore; Biochemical; Bioenergetics; Exercise; Gait speed; Height; Longitudinal Studies; Magnetic Resonance Spectroscopy; Measurement; Metabolic; Methods; Muscle; Outcome; Outcome Measure; Oxygen Consumption; Participant; Performance; Phosphocreatine; Phosphorus; Physiological; Population; Recovery; Testing; Treadmill Tests; Walking; Weight; age related; aged; human subject; men; performance tests; sex; walking speed

We are performing extensive dynamic 31P exercise studies in the BLSA population too develop bioenergetic correlates of aging, walking speed, and other outcome measures from the BLSA. Aerobic fitness and muscle bioenergetic capacity decline with age; whether such declines explain age-related slowing of walking speed is unclear. We hypothesized that muscle energetics and aerobic capacity are independent correlates of walking speed in simple and challenging performance tests and that they account for the observed age-related decline in walking speed in these same tests. Muscle bioenergetics was assessed as postexercise recovery rate of phosphocreatine (PCr), kPCr, using phosphorus magnetic resonance spectroscopy (31P-MRS) in 126 participants (53 men) of the Baltimore Longitudinal Study of Aging aged 2691 years (mean = 72 years). Four walking tasks were administeredusual pace over 6 m and 150 seconds and fast pace over 6 m and 400 m. Separately, aerobic fitness was assessed as peak oxygen consumption (peak VO2) using a graded treadmill test. We found that all gait speeds, kPCr, and peak VO2 were lower with older age. Independent of age, sex, height, and weight, both kPCr and peak VO2 were positively and significantly associated with fast pace and long distance walking but only peak VO2 and not kPCr was significantly associated with usual gait speed over 6 m. Both kPCr and peak VO2 substantially attenuated the association between age and gait speed for all but the least stressful walking task of 6 m at usual pace. Overall, muscle bioenergetics assessed using 31P-MRS is highly correlated with walking speed and partially explains age-related poorer performance in fast and long walking tasks.

我们正在BLSA人群中进行广泛的动态31p运动研究，也发展了BLSA的衰老，步行速度和其他结果指标的生物能量相关性。有氧健身和肌肉生物能力随着年龄的增长而下降；这种下降是否解释了与年龄相关的步行速度的放缓尚不清楚。我们假设肌肉能量和有氧能力是步行速度的独立相关性，在简单而挑战性的性能测试中，它们解释了这些相同测试中与年龄相关的步行速度下降。 在巴尔的摩（Baltimore）纵向研究2691年的巴尔的摩纵向研究中，使用磷磁共振光谱（31p-MRS）评估了肌肉生物能量作为运动后（PCR）（PCR），KPCR的恢复率（PCR），KPCR（31p-MRS）。在6 m和150秒的时间内进行四个步行任务，并在6 m和400 m的速度上进行速度和快速速度。另外，使用分级的跑步机测试将有氧健身评估为峰值消耗量（峰值VO2）。 我们发现，随着年龄的增长，所有步态速度，KPCR和峰值VO2均较低。 KPCR和峰值VO2与年龄，性别，身高和体重无关，与快速步行和长距离步行呈正相关，但只有峰值VO2而不是KPCR与6 m以上通常的步态速度显着相关。 KPCR和Peak VO2都大大衰减了在通常的速度下6 m压力的步行任务以外的所有人之间的年龄和步态速度之间的关联。 总体而言，使用31p-MRS评估的肌肉生物能力与步行速度高度相关，并且部分解释了与年龄相关的较差的步行任务中的性能较差。