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Matsumura, C. Y.

Publications and source records attributed to Matsumura, C. Y..

2 recordsLinked to original sources

Characterization of walking locomotion in aged C57BL/10 mice: a comprehensive gait analysis

Rodent gait analysis is crucial for modeling human aging, but the lack of comprehensive research on gait in elderly mice limits our ability to translate findings from animal models to human populations. Age-related changes in C57BL/10 strain remain unknown. The state of art protocol for gait analysis uses the CatWalk XT system that allows an understanding of the locomotion pattern by a variety of parameters. We aim to provide relevant information for experimental designs, presenting benchmark data on the performance of locomotion using healthy wild-type mice for future preclinical investigations of neurological and neuromuscular gait patterns. In this study, characterization of walking locomotion was demonstrated from complete gait analysis in aged C57BL/10ScCr/PasUnib mice using open-field, CatWalk, and treadmill tests. Mice were divided into the adult group (6 months; n = 9) and the aged group (20 months; n = 9). Aged mice demonstrated decreased mobility, distance traveled, and general speed in the open-field test. The spatiotemporal and kinetic parameters were altered in aged mice, with lower speed, higher stand time and stride length, and increased base of support and duty cycle in comparison with adult mice. Interlimb coordination has changed in elderly mice. To test whether speed alters the temporal parameters, we used a treadmill test and we demonstrated higher stand time in 20-month-old mice. We demonstrated that changes in gait parameters and mobility represent direct age-related singularities in the wild-type C57BL/10 mice. Overall, aged mice took more time in contact with the ground independently of the speed. These baseline gait results shed light on measures that allow the potential investigation of therapeutics and interventions in gerontology or neuromuscular diseases.

animal behavior and cognition↗

High-fat diet suppresses the positive effect of creatine supplementation on skeletal muscle function by reducing protein expression of IGF-PI3K-AKT-mTOR pathway

High-fat (HF) diets in combination with sedentary lifestyle represent one of the major public health concerns predisposing to obesity and diabetes leading to skeletal muscle atrophy, decreased fiber diameter and muscle mass with accumulation of fat tissue resulting in loss of muscle strength. One strategy to overcome the maleficent effects of HF diet is resistance training, a strategy used to improve muscle mass, reverting the negative effects on obesity-related changes in skeletal muscle. Together with resistance training, supplementation with creatine monohydrate (CrM) in the diet has been used to improve muscle mass and strength. Creatine is a non-essential amino acid that is directly involved in the cross-bridge cycle providing a phosphate group to ADP during the initiation of muscle contraction. Besides its antioxidant and anti-inflammatory effects CrM also upregulates IGF-1 resulting in hyperthophy with an increase in muscle function. However, it is unknown whether CrM supplementation during resistance training would revert the negative effects of high-fat diet on the muscle performance. During 8 weeks we measured muscle performance to climb a 1.1m and 80{degrees} ladder with increasing load on trained rats that had received standard diet or high-fat diet, supplemented or not with CrM. We observed that the CrM supplementation up-regulated IGF-1 and phospho-AKT protein levels, suggesting an activation of the IGF1-PI3K-Akt/PKB-mTOR pathway. Moreover, despite the CrM supplementation, HF diet down-regulated several proteins of the IGF1-PI3K-Akt/PKB-mTOR pathway, suggesting that diet lipid content is crucial to maintain or improve muscle function during resistance training.

physiology↗