Dataset Information

Vitamin D Insufficiency Reduces Grip Strength, Grip Endurance and Increases Frailty in Aged C57Bl/6J Mice.

ABSTRACT: Low 25-OH serum vitamin D (VitD) is pervasive in older adults and linked to functional decline and progression of frailty. We have previously shown that chronic VitD insufficiency in "middle-aged" mice results in impaired anaerobic exercise capacity, decreased lean mass, and increased adiposity. Here, we examine if VitD insufficiency results in similar deficits and greater frailty progression in old-aged (24 to 28 months of age) mice. Similar to what we report in younger mice, older mice exhibit a rapid and sustained response in serum 25-OH VitD levels to differential supplementation, including insufficient (125 IU/kg chow), sufficient (1000 IU/kg chow), and hypersufficient (8000 IU/kg chow) groups. During the 4-month time course, mice were assessed for body composition (DEXA), physical performance, and frailty using a Fried physical phenotype-based assessment tool. The 125 IU mice exhibited worse grip strength (p = 0.002) and inverted grip hang time (p = 0.003) at endpoint and the 8000 IU mice transiently displayed greater rotarod performance after 3 months (p = 0.012), yet other aspects including treadmill performance and gait speed were unaffected. However, 125 and 1000 IU mice exhibited greater frailty compared to baseline (p = 0.001 and p = 0.038, respectively), whereas 8000 IU mice did not (p = 0.341). These data indicate targeting higher serum 25-OH vitamin D levels may attenuate frailty progression during aging.

SUBMITTER: Seldeen KL

PROVIDER: S-EPMC7599884 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature

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Vitamin D Insufficiency Reduces Grip Strength, Grip Endurance and Increases Frailty in Aged C57Bl/6J Mice.

Seldeen Kenneth Ladd KL Berman Reem Nagi RN Pang Manhui M Lasky Ginger G Weiss Carleara C MacDonald Brian Alexander BA Thiyagarajan Ramkumar R Redae Yonas Y Troen Bruce Robert BR

Nutrients 20200930 10

Low 25-OH serum vitamin D (VitD) is pervasive in older adults and linked to functional decline and progression of frailty. We have previously shown that chronic VitD insufficiency in "middle-aged" mice results in impaired anaerobic exercise capacity, decreased lean mass, and increased adiposity. Here, we examine if VitD insufficiency results in similar deficits and greater frailty progression in old-aged (24 to 28 months of age) mice. Similar to what we report in younger mice, older mice exhibit ...[more]

PMID: 33007912

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Dataset Information

Vitamin D Insufficiency Reduces Grip Strength, Grip Endurance and Increases Frailty in Aged C57Bl/6J Mice.

Publications

Vitamin D Insufficiency Reduces Grip Strength, Grip Endurance and Increases Frailty in Aged C57Bl/6J Mice.

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