Changes in oxidative stress severity and antioxidant potential during muscle atrophy and reloading in mice.

[Purpose] Changes in oxidative stress severity and antioxidant potential are routinely used as oxidative stress markers. While several studies have reported the relationship between these markers and exercise, little is known about the dynamic nature of these markers during muscle atrophy and reloading. Therefore, we examined changes in oxidative stress severity and antioxidant potential during muscle atrophy and reloading. [Subjects and Methods] Muscle atrophy was induced in mice by casting the limb for 2 weeks. Mice were then subjected to reloading for 2 weeks. The severity of oxidative stress (hydroperoxide) and antioxidant potential (degree of reduction) were quantified. [Results] Muscle atrophy was induced by cast immobilization. The muscle mass of mice recovered to similar levels as the control group following 2 weeks of reloading. The degree of oxidative stress was within the normal range throughout the experimental period. The antioxidant potential decreased to the clinical borderline level 2 weeks after immobilization, further decreased after 1 day of reloading, and then recovered to within the normal range. [Conclusion] Performing d-ROMs and BAP tests may contribute to the understanding to atrophic process of skeletal muscle in clinical practice of physical therapy.

Relationship between outcome in acute stroke patients and multiple stroke related scores obtained after onset of stroke.

[Purpose] The purpose of this study is to examine the effectiveness of a stroke-related scale with regard to outcome, onset, and timing of stroke patients. [Participants and Methods] The participants included 583 out of 996 patients who were admitted to the stroke care unit.The outcomes and 3 stroke scale (National Institutes of Health Stroke Scale: NIHSS, Functional Independence Measure: FIM, modified Rankin Scale: mRS) scores immediately at hospitalization, on day 7 after onset, and on day 30 after onset were investigated. This study was analyzed using a generalization linear model with a binomial distribution. The comparisons between outcomes were made in terms of home discharge versus convalescence, and convalescence versus hospital transfer. [Results] Comparisons of home discharge versus convalescence hospital transfer showed a significant difference in the NIHSS and mRS scores at the time of hospitalization, and a significant difference in the NIHSS scale score on day 7 after onset. In comparisons between convalescence and hospital transfer, significant differences were observed in NIHSS and FIM scores at hospitalization, and the FIM scale score showed significant differences on day 7 and day 30. [Conclusion] The study suggested the efficacy of using multiple scales for prediction of stroke outcome with higher accuracy.

A new model of skeletal muscle atrophy induced by immobilization using a hook-and-loop fastener in mice.

[Purpose] To study muscle atrophy, the muscle atrophy model mice have been used frequently. In particular, cast immobilization is the most common method to induce muscle atrophy. However, it is time consuming and often causes adverse events including skin injury, edema, and necrosis. The present study, we developed a hook-and-loop fastener (Velcro) immobilization method as a new, simple, and less invasive approach to induce muscle atrophy. [Subjects and Methods] Mice were bandaged in the knee joint extension and ankle plantar extension position. Muscle atrophy was induced by either winding a cast or Velcro around the limb. [Results] According to weight and fiber size, Velcro immobilization induced equivalent muscle atrophy to cast immobilization. Velcro immobilization reduced significantly the time for the procedure and the frequency of adverse events. [Conclusion] Velcro immobilization can induce muscle atrophy comparable to cast immobilization, but in a shorter time and with less complications. Velcro immobilization may contribute to the study of disuse muscle atrophy in clinical practice of physical therapy using a mouse model.

Effects of inactivity and exercise intervention on brain-derived neurotrophic factor in mice: Comparison of kinetics in serum, skeletal muscle, and brain.

Exercise training increases brain-derived neurotrophic factor (BDNF) expression and improves cognitive function. However, the dynamics of BDNF during inactivity and the effects of exercise intervention on BDNF levels have rarely been examined. Therefore, we aimed to examine changes in serum, skeletal muscle, and brain BDNF levels under these conditions. Mice were divided into control (Co), cast immobilization (CI), reloading (RL), and exercise (Ex) groups. Muscle atrophy was induced by cast immobilization for 2 weeks in the CI, RL, and Ex groups. After cast removal, the RL and Ex groups underwent regrounding and treadmill exercise, respectively, for 2 weeks. Serum, skeletal muscle, and brain BDNF levels showed a similar decreasing trend in the CI group, recovery in the RL group, and a further increase in the Ex group compared with those in the Co group. This indicates that BDNF levels change in parallel with the degree of activity. However, the magnitude of variation differed among the tissues in the order of serum > skeletal muscle > brain tissue. These results suggest that different mechanisms in different tissues regulate BDNF expression. BDNF could potentially act as an objective measure of the impact of both inactivity and exercise-based interventions.

Identification of the Core Activate Position for a Seated Subject: Proposal of a new Exercise Method for Maintenance Rehabilitation.

OBJECTIVES: This study aimed to identify a position for core muscle activation (core activate position) for a seated subject and to design an exercise method using this position for rehabilitation during the daily maintenance or maintenance stages. METHODS: Thirteen young men participated as subjects in this study. We manufactured a chair in which the seat had an adjustable forward tilt angle. The subjects underwent ultrasonographic measurements of the thickness of the transversus abdominis, internal oblique, and external oblique muscles while sitting in the chair with the seat angle adjusted to 0°, 6°, or 12°. Further, we conducted image analysis to determine the positional relationships of these muscles using the following four points as landmarks: the anterior superior iliac spine, the posterior superior iliac spine, the fourth lumbar vertebra, and the seventh thoracic vertebra. RESULTS: Significant increases in the thickness of the transversus abdominis and external oblique muscles were observed when the seat forward tilt angle was adjusted to 12° (P <0.05). In the core activate position (which demonstrated effective activation of the transversus abdominis), the posterior superior iliac spine, the fourth lumbar vertebra, and the seventh thoracic vertebra were aligned in a straight line that was nearly perpendicular to the line connecting the anterior superior iliac spine and the posterior superior iliac spine. CONCLUSIONS: This postural guidance can be applied to core exercise methods during maintenance rehabilitation.