{"doi":"10.3390/nu12103005","title":"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.","journal":"Nutrients","year":2020,"id":98051,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":32,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9562,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2020-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":485551,"name":"Reem Nagi Berman","orcid":null,"position":1,"is_corresponding":false},{"id":485552,"name":"Manhui Pang","orcid":null,"position":2,"is_corresponding":false},{"id":485553,"name":"Ginger Lasky","orcid":null,"position":3,"is_corresponding":false},{"id":484460,"name":"Carleara Weiss","orcid":"0000-0003-4421-0985","position":4,"is_corresponding":false},{"id":484461,"name":"Brian A. MacDonald","orcid":"0009-0001-1785-4833","position":5,"is_corresponding":false},{"id":484462,"name":"Ramkumar Thiyagarajan","orcid":"0000-0003-0188-7363","position":6,"is_corresponding":false},{"id":485554,"name":"Yonas Redae","orcid":null,"position":7,"is_corresponding":false},{"id":484463,"name":"Bruce R. Troen","orcid":"0000-0002-3699-0021","position":8,"is_corresponding":false},{"id":484459,"name":"Kenneth L. Seldeen","orcid":"0000-0003-1989-6698","position":0,"is_corresponding":true}],"reference_count":49,"raw_metadata":null,"created_at":"2026-07-18T22:36:34.157932Z","pmid":"33007912","pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}