在老年男性和女性短期禁食期间基质利用
San Wang1, Rita H Tsay1, Danya Zhang1,2
1Laboratory of Human Nutrition and Clinical Research Center, Massachusetts Institute of Technology, Cambridge, MA.
American journal of physiology. Endocrinology and metabolism
|February 4, 2026
概括
与年轻人相比,接受短期禁食的老年人对蛋白质分解的依赖性增加. 这种持续的蛋白质氧化可能会增加他们在疾病或营养摄入不足期间肌肉损失的风险.
科学领域:
- 老年学是一门学科.
- 人体生理学 人体生理学
- 营养科学 营养科学
背景情况:
- 衰老会改变身体的组成和代谢调节,这可能会影响禁食期间的营养利用.
- 老年人容易发生非自愿的禁食,但他们的巨量营养素代谢在禁食期间尚不清楚.
研究的目的:
- 在36小时的禁食期间,系统地评估老年人与年轻人的宏观营养素调动和氧化.
- 调查短期禁食对代谢反应的年龄相关差异.
主要方法:
- 双能X射线吸收计用于测量身体成分.
- 对10名老年 (60-81岁) 和10名年轻 (18-35岁) 的健康成年人实施了36小时的禁食.
- 测量包括蛋白质调动,脂解,葡萄糖输出和蛋白质,脂肪和碳水化合物的氧化.
主要成果:
- 禁食增加脂肪氧化和减少碳水化合物氧化在两个年龄组.
- 与年轻人相比,老年人保持了较高的相对蛋白质氧化 (16-18%的REE).
- 对于葡萄糖生产,脂解和蛋白质周转标记物,观察到显著的年龄-禁食相互作用.
结论:
- 年长的成年人表现出淡的葡萄糖和白氨酸反应,但在短期禁食期间持续的蛋白质氧化.
- 这些发现表明,老年人更依赖蛋白质代谢,可能会增加对肌肉损失的脆弱性.
- 与年龄相关的代谢差异突出显示,在面临禁食或疾病的老年人群中需要量身定制的营养支持.
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