Baumann Cory W, Kwak Dongmin, Thompson LaDora V
Divisions of Rehabilitation Science and Physical Therapy, Department of Rehabilitation Medicine, Medical School, University of Minnesota, Minneapolis, MN 55455, USA.
Department of Physical Therapy and Athletic Training, Boston University, Boston, MA 02215, USA.
Aging (Albany NY). 2019 Jul 29;11(14):5206-5214. doi: 10.18632/aging.102114.
Many age-related biochemical, physiological and behavioral changes are known to be sex-specific. However, how sex influences frailty status and mortality risk in frail rodents has yet to be established. The purpose of this study was therefore to characterize sex differences in frail mice across the lifespan. Male (n=29) and female (n=27) mice starting at 17 months of age were assessed using a frailty phenotype adjusted according to sex, which included body weight, walking speed, strength, endurance and physical activity. Regardless of sex, frail mice were phenotypically dysfunctional compared to age-matched non-frail mice, while non-frail females generally possessed a higher body fat percentage and were more physically active than non-frail males (p≤0.05). The prevalence of frailty was greater in female mice at 26 months of age (p=0.05), but if normalized to mean lifespan, no sex differences remained. No differences were detected in the rate of death or mean lifespan between frail male and female mice (p≥0.12). In closing, these data indicate that sexual differences exist in aging C57BL/6 mice and if the frailty criteria are adjusted according to sex, the prevalence of frailty increases across age with frail mice dying early in life, regardless of sex.
已知许多与年龄相关的生化、生理和行为变化具有性别特异性。然而，性别如何影响脆弱啮齿动物的脆弱状态和死亡风险尚未明确。因此，本研究的目的是描述不同年龄段脆弱小鼠的性别差异。对起始月龄为17个月的雄性（n = 29）和雌性（n = 27）小鼠，使用根据性别调整的脆弱表型进行评估，该表型包括体重、行走速度、力量、耐力和身体活动。无论性别如何，与年龄匹配的非脆弱小鼠相比，脆弱小鼠在表型上存在功能障碍，而非脆弱雌性小鼠的体脂百分比通常高于非脆弱雄性小鼠，且身体活动更频繁（p≤0.05）。26月龄雌性小鼠的脆弱发生率更高（p = 0.05），但如果按平均寿命进行标准化，则不存在性别差异。在脆弱的雄性和雌性小鼠之间，未检测到死亡率或平均寿命的差异（p≥0.12）。总之，这些数据表明，衰老的C57BL/6小鼠存在性别差异，并且如果根据性别调整脆弱标准，随着年龄增长，脆弱发生率会增加，脆弱小鼠在生命早期死亡，无论性别如何。
