Evidence map›Paper›PMID 42003315›Full record

ArticleGeriatrics & gerontology international2026

Combined Effects of Protein/Fat Deficiency and Disuse on Skeletal Muscle Mass and Function in Mice.

Koichi Toyoshima, Bo-Kyung Son, Miya Oura, Zehan Song, Michiko Nanao-Hamai, Sumito Ogawa, Masahiro Akishita

Abstract read
In one paragraph

Article in Geriatrics & gerontology international, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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0citing papers in PubMed
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1 · What the graph read from it

What it found

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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

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3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

7 authors.

Koichi ToyoshimaDepartment of Geriatric Medicine, The University of Tokyo, Tokyo, Japan.ORCID https://orcid.org/0009-0007-6174-7270
Bo-Kyung SonDepartment of Geriatric Medicine, The University of Tokyo, Tokyo, Japan.ORCID https://orcid.org/0009-0002-2900-6871
Miya OuraDepartment of Geriatric Medicine, The University of Tokyo, Tokyo, Japan.ORCID https://orcid.org/0009-0005-3479-4456
Zehan SongDepartment of Geriatric Medicine, The University of Tokyo, Tokyo, Japan.
Michiko Nanao-HamaiDepartment of Geriatric Medicine, The University of Tokyo, Tokyo, Japan.
Sumito OgawaDepartment of Geriatric Medicine, The University of Tokyo, Tokyo, Japan.ORCID https://orcid.org/0000-0002-5935-276X
Masahiro AkishitaTokyo Metropolitan Institute for Geriatrics and Gerontology, Tokyo, Japan.

Funding

JSPS KAKENHI 23H02811
6 · The paper itself

Abstract

backgroundSarcopenia is driven by multifactorial insults, including undernutrition and disuse; however, the causal links between inadequate nutrition and the loss of muscle mass and strength remain unclear. This study aimed to establish mouse models of protein and/or fat deficiency and to investigate their interaction with disuse on skeletal muscle.

methodsNine-week-old male C57BL/6J mice fed isocaloric diets for 8 weeks: normal chow (NC), low fat (LF), low protein (LP), or low protein and low fat (LPLF). Outcomes included body weight, grip strength test, gastrocnemius and soleus muscle weights, cross-sectional area (CSA) of gastrocnemius muscle fibers, and gastrocnemius muscle mRNA expression of ubiquitin-proteasome system (UPS) markers (atrogin-1, MuRF1) and inflammatory cytokines (TNF-α, IL-6, IL-1β). After the 8-week diet phase, a disuse model using bilateral hindlimb immobilization for 1, 3, or 7 days was applied under continued isocaloric feeding to assess diet-disuse interactions.

resultsCompared with NC, the LF, LP, and LPLF groups showed reduced body weight, grip strength, muscle mass, and myofiber CSA. Upregulation of UPS-related genes was observed in LPLF, whereas the expression of inflammation-related genes did not differ from NC in LF, LP, and LPLF. When combined with immobilization, LP and LPLF diets further exacerbated the decreases in muscle mass and strength compared with NC, accompanied by increased expression of both UPS- and inflammation-related genes.

conclusionsAn animal model of diet-induced reduction in muscle mass and strength was established, which will be useful for investigating the effects of protein and fat deficiency on skeletal muscle. Elucidating the detailed molecular pathways involved remains an important goal for future research and may provide new insights into nutritional approaches to prevent or treat sarcopenia.

Indexed as

Muscle, SkeletalProtein DeficiencySarcopeniaAnimalsBody WeightDisease Models, AnimalMaleMiceMice, Inbred C57BLMuscle Strength

Identifiers

PMID42003315
PMCPMC13093123

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.