Evidence map›Paper›PMID 42442691›Full record

ArticleMolecular metabolism2026

CaMKIIγ/δ contributes to mitochondrial metabolic adaptation in skeletal muscle during endurance training.

Ryoka Tsukahara, Yasuo Kitajima, Yuka Ichihashi, Hikaru Iwase, Shun Ohki, Yusuke Sotomaru, Tomohiro Kurosaki, Yohei Kawano, Tomoharu Yasuda

Abstract read
In one paragraph

Article in Molecular metabolism, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
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

The trial behind it

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3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. Article
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

9 authors.

Ryoka TsukaharaDepartment of Immunology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan.
Yasuo KitajimaDepartment of Immunology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan. Electronic address: kitajima@hiroshima-u.ac.jp.
Yuka IchihashiDepartment of Immunology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan.
Hikaru IwaseDepartment of Immunology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan.
Shun OhkiFaculty of Environmental Engineering, The University of Kitakyushu, Fukuoka, Japan.
Yusuke SotomaruCore Facility Management Center, Hiroshima University, Hiroshima, Japan.
Tomohiro KurosakiLaboratory for Lymphocyte Differentiation, RIKEN Center for Integrative Medical Sciences (IMS), Yokohama, Japan.
Yohei KawanoDepartment of Immunology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan.
Tomoharu YasudaDepartment of Immunology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan. Electronic address: yasudat@hiroshima-u.ac.jp.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundCalcium/calmodulin-dependent protein kinase II (CaMKII) is activated in skeletal muscle with exercise, yet its physiological role in endurance training adaptation remains unclear. This study determined whether endogenous CaMKIIγ/δ in skeletal muscle is required for endurance training-induced metabolic remodeling and exercise adaptation.

methodsWe generated male skeletal muscle-specific CaMKIIγ/δ knockout (CaMKII mKO) mice and assessed muscle phenotype, exercise capacity, and training adaptation. Acute exercise-induced CaMKII activation was evaluated by phosphorylation status. Transcriptomic changes were analyzed by RNA sequencing before and after 4 weeks of treadmill endurance training. Mitochondrial protein abundance, ultrastructure, and bioenergetics were examined by immunoblotting, transmission electron microscopy, and Seahorse extracellular flux analysis in myotubes with acute CaMKIIγ/δ deletion.

resultsAcute treadmill exercise induced CaMKII phosphorylation in muscle without altering total CaMKII abundance. CaMKII mKO mice showed normal muscle mass, grip strength, and baseline performance. However, endurance training-induced improvement in running capacity was significantly blunted. Transcriptomic analyses revealed downregulation of oxidative phosphorylation and glycolytic gene programs in CaMKII-deficient muscle at baseline and after training. OXPHOS complex protein abundance was partially reduced at baseline and markedly reduced across complexes I-V after training. CaMKII deficiency increased ultrastructurally abnormal mitochondria without reducing mitochondrial number. Consistently, CaMKII-deficient myotubes showed lower absolute per-well oxygen consumption and extracellular acidification rate.

conclusionsIn male mice, endogenous CaMKIIγ/δ in muscle is dispensable for baseline locomotor performance but essential for endurance training-induced metabolic remodeling and mitochondrial integrity. These findings support a role for CaMKII in linking contraction-induced calcium signaling to metabolic adaptation in muscle.

Indexed as

Calcium-Calmodulin-Dependent Protein Kinase Type 2Endurance TrainingMitochondriaMitochondria, MuscleMuscle, SkeletalAdaptation, PhysiologicalAnimalsEnergy MetabolismMaleMiceMice, Inbred C57BLMice, KnockoutOxidative PhosphorylationPhosphorylationPhysical Conditioning, AnimalCalcium-Calmodulin-Dependent Protein Kinase Type 2CaMKIIEndurance trainingExercise adaptationMitochondrial metabolismOxidative phosphorylationSkeletal muscle

Identifiers

PMID42442691
PMCPMC13427457

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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.