Division of Geriatric Endocrinology, the First Affiliated Hospital of Nanjing Medical University, People's Republic of China.
Division of Geriatric Respiratory, the First Affiliated Hospital of Nanjing Medical University, People's Republic of China.
J Gerontol A Biol Sci Med Sci. 2021 Feb 25;76(3):393-399. doi: 10.1093/gerona/glaa070.
Age-related adipose tissue dysfunction is potentially important in the development of insulin resistance and metabolic disorder. Caloric restriction (CR) is a robust intervention to reduce adiposity, improve metabolic health, and extend healthy life span. Both white adipose tissue (WAT) and brown adipose tissue (BAT) are involved in energy homeostasis. CR triggers the beiging of WAT in young mice; however, the effects of CR on beiging of WAT and function of BAT during aging are unclear. This study aimed to investigate how age and CR impact the beiging of WAT, the function of BAT, and metabolic health in mice. C57BL/6 mice were fed CR diet (40% less than the ad libitum [AL] diet) for 3 months initiated in young (3 months), middle-aged (12 months), and old (19 months) stage. We found age-related changes in different types of adipose tissue, including adipocyte enlargement, declined beiging of WAT, and declined thermogenic and β-oxidational function of BAT. Moreover, CR attenuated age-associated adipocyte enlargement and prevented the age-related decline in beiging potential of WAT. These protective effects on the beiging potential were significant in inguinal WAT at all three ages, which were significant in epididymal WAT at young and old age. In contrast, thermogenic and β-oxidational function of BAT further declined after CR in the young age group. In conclusion, our findings reveal the contribution of WAT beiging decline to age-related metabolic disorder and suggest nutritional intervention, specifically targeting WAT beiging, as an effective approach to metabolic health during aging.
年龄相关的脂肪组织功能障碍在胰岛素抵抗和代谢紊乱的发展中具有重要意义。热量限制（CR）是一种减少肥胖、改善代谢健康和延长健康寿命的强大干预措施。白色脂肪组织（WAT）和棕色脂肪组织（BAT）都参与能量稳态。CR 可引发年轻小鼠 WAT 的褐色化；然而，CR 对衰老过程中 WAT 的褐色化和 BAT 功能的影响尚不清楚。本研究旨在探讨年龄和 CR 如何影响 WAT 的褐色化、BAT 的功能和小鼠的代谢健康。C57BL/6 小鼠在年轻（3 个月）、中年（12 个月）和老年（19 个月）阶段开始接受 CR 饮食（比自由进食[AL]饮食少 40%）3 个月。我们发现不同类型脂肪组织的年龄相关变化，包括脂肪细胞增大、WAT 褐色化减少以及 BAT 的产热和β-氧化功能下降。此外，CR 减弱了与年龄相关的脂肪细胞增大，并防止了 WAT 褐色化潜力随年龄的下降。这些对褐色化潜力的保护作用在所有三个年龄段的腹股沟 WAT 中均显著，在年轻和老年的附睾 WAT 中也显著。相比之下，在年轻年龄组中，CR 后 BAT 的产热和β-氧化功能进一步下降。总之，我们的研究结果揭示了 WAT 褐色化减少对与年龄相关的代谢紊乱的贡献，并表明营养干预，特别是针对 WAT 褐色化，是衰老过程中代谢健康的有效方法。
