Abstract: SA-PO0869
Magnetic Stimulation Improves the Progression of Immobilization-Induced Muscle Atrophy in Rats
Session Information
- Health Maintenance, Nutrition, and Metabolism
October 24, 2026 | Location: Exhibit Hall A, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Health Maintenance, Nutrition, and Metabolism
- 1500 Health Maintenance, Nutrition, and Metabolism
Authors
- Kwoun, Giyoung, Division of Nephrology and Endocrinology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan
- Nishi, Hiroshi, Division of Nephrology and Endocrinology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan
- Takahashi, Hironobu, Institute of Advanced Biomedical Engineering and Science, Tokyo Women's Medical University, Tokyo, Japan
- Sekino, Masaki, Graduate School of Engineering, The University of Tokyo, Tokyo, Japan
- Nangaku, Masaomi, Division of Nephrology and Endocrinology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan
- Mimura, Imari, Division of Nephrology and Endocrinology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan
Background
Patients with chronic kidney disease are characterized by persistent chronic inflammation, which promotes muscle protein degradation, as well as muscle mass loss caused by metabolic acidosis and malnutrition. They are prone to uremic sarcopenia, in which reduced muscle strength is closely associated with increased mortality. Electrical stimulation has been used as a therapeutic approach; however, it has limitations, including the potential to cause pain and the inability to effectively stimulate deep tissues. As an alternative, magnetic stimulation can non-invasively induce skeletal muscle contraction without direct contact, offering a potentially less invasive treatment option. In this study, we evaluated the therapeutic effects and underlying mechanisms of magnetic stimulation in a rat model of muscle atrophy induced by hindlimb immobilization.
Methods
Rats were allocated into three experimental groups: a control group (n=5), a group subjected to hindlimb muscle atrophy induced by spiral wire immobilization (SWI) (n=6), and an SWI group treated with magnetic stimulation (n=5). Magnetic stimulation was delivered at 30 Hz with an intensity of 25%, comprising 800 trains and a total of 12,000 pulses per day for 5 consecutive days. Muscle strength was assessed, and the soleus and gastrocnemius muscles were subsequently collected for transcriptomic and metabolomic analyses.
Results
The SWI group showed significantly reduced body weight and decreased soleus and gastrocnemius muscle mass compared with controls (p < 0.05). In contrast, SWI rats treated with magnetic stimulation exhibited significantly increased gastrocnemius muscle weight and maximal knee extension twitch torque (p < 0.05). RNA sequencing identified 469 genes downregulated by SWI, while magnetic stimulation upregulated 190 genes. Metabolomic analysis indicated that SWI affected glutathione metabolism, whereas magnetic stimulation altered purine metabolism, partly supported by transcriptomic data.
In engineered human skeletal muscle tissues, treatment with 1 μM L-alanosine, a purine metabolism inhibitor, impaired electrically induced contractile function, with significant reductions in twitch and tetanic force compared with controls (p < 0.05).
Conclusion
Magnetic stimulation mitigated immobilization-induced loss of gastrocnemius muscle mass and function, and may slow sarcopenia by modulating muscle metabolism.
Acknowledgment
Our sincere gratitude goes to Seiko Funatani and Keigo Morita (the University of Tokyo), Karina Kozaki and Koichi Nakazato (Nippon Sports University) and Takehito Sugasawa and Jiawei Wan ( Tsukuba University) for their technical assistance.
Funding
- Government Support – Non-U.S.