Exercise Reverses Amyloid ß-Peptide-Mediated Cognitive Deficits in Alzheimer's Disease Mice Expressing Mutant Presenilin-2.

PURPOSE: The molecular mechanisms by which physical exercise produces beneficial effects on pathologic features and behavioral symptoms of Alzheimer's disease (AD) are not well understood. Herein, we examined whether regular moderate exercise could improve cognitive function and produce transcriptomic responses in the brain. METHODS: Four groups of mice were studied: nontransgenic control, mice expressing the human presenilin-2 wild type, mice expressing the human presenilin-2 with the N141I mutation (Tg-PS2m), and Tg-PS2m that were subjected to treadmill exercise (TE) at a speed of 10 m·min-1 for 50 min·d-1, 5 d·wk-1, for 6 wk (Tg-PS2m/Ex). RESULTS: Tg-PS2m/Ex mice exhibited increased preference in exploring a novel object than Tg-PS2m in the novel object recognition test, whereas differences observed in the water maze test and passive avoidance test were not significant. Western blot and histological analyses using amyloid oligomer (A11) and ß-amyloid (6E10) antibody indicated that amyloid oligomer-reactive bands and plaque deposition in the hippocampus were reduced, although not significantly, after TE. Transcriptomic (RNA-sequencing) analysis and subsequent protein analysis revealed that the cell cycle regulatory gene, Cdc28 protein kinase regulatory subunit 2 (Cks2), was decreased, and the cell cycle- and apoptotic cell death-related factors, including cyclin D1, proliferating cell nuclear antigen, and cleaved caspase-3, were increased in the hippocampus of Tg-PS2m, whereas TE reversed their altered expression. CONCLUSIONS: The results support the hypothesis that the pathologic features and behavioral symptoms of AD caused by accumulation of amyloid ß-peptide in hippocampus, causing aberrant cell cycle reentry and apoptosis, can be reversed by regular exercise.

Comparison of maximum muscle strength and isokinetic knee and core muscle functions according to pedaling power difference of racing cyclist candidates.

The purpose of this study was to investigate differences of maximum muscle strength and isokinetic knee and core muscle functions according to pedaling power of racing cyclist candidate. Subjects for this study were 200 racing cyclist candidates and divided into four groups: top 10% peak power group (TPP, n=20), low 10% peak power group (LPP, n=20), top 10% average power group (TAP, n=20), and low 10% average power group (LAP, n=20). The maximum muscle strength was consisted of grip strength, bench press and squat measured by Ariel device, and isokinetic knee and core muscle functions were analyzed by Humac Norm device. Significant differences between groups were determined with one-way repeated analysis of variance. As the result of this study, TPP and TAP groups showed significantly decreased body-fat mass and increased free fat mass when compared to LPP and LAP groups. The maximum strength of grip and squat was significantly higher in TPP and TAP than in other groups. Isokinetic knee extension and flexion strength was higher in TPP and TAP groups as well as isokinetic trunk extension and flexion functions were highest in TPP group. Thus, our findings suggest new evidence that muscle mass, maximal muscle strength, and isokinetic muscle functions might be important predictors of racing cyclist performance.

The relationship between physical activity levels and metabolic syndrome in male white-collar workers.

[Purpose] Physical activity is important for preventing and managing metabolic syndrome. White-collar workers can be inherently predisposed to chronic diseases, as their jobs are primarily sedentary. The purpose of this study was to examine the relationship between physical activity and metabolic syndrome in male white-collar workers. [Subjects and Methods] Physical activity and metabolic syndrome factors were measured in 331 male public office workers. Physical activity was classified as high (N=101), moderate (N=115), or low (N=111) using the International Physical Activity Questionnaire. To diagnose metabolic syndrome, the U.S. National Cholesterol Education Program's standard was used. [Results] Waist circumference and triglyceride levels, factors of metabolic syndrome, were significantly higher in the low physical activity group than in the moderate or high activity group. High-density lipoprotein cholesterol was significantly lower in the low physical activity group than in the moderate or high activity group. Waist circumference and fasting glucose were negatively correlated with physical activity level, and HDL cholesterol showed a positive correlation with waist circumference. The odds ratios for metabolic syndrome were 2.03 times higher (95% confidence interval, 1.01-4.09) in the low physical activity group than in the high physical activity group. [Conclusion] Low physical activity was a risk factor for metabolic syndrome in white-collar workers. Therefore, increasing physical activity in daily life may prevent metabolic syndrome in white-collar workers.

Effects of aerobic exercise on the resting heart rate, physical fitness, and arterial stiffness of female patients with metabolic syndrome.

[Purpose] The purpose of this study was to investigate the effects of aerobic exercise on the resting heart rate, physical fitness, and arterial stiffness or female patients with metabolic syndrome. [Subjects and Methods] Subjects were randomly assigned to an exercise group (n=12) or a control group (n=11). Subjects in the exercise group performed aerobic exercise at 60-80% of maximum heart rate for 40 min 5 times a week for 12 weeks. The changes in metabolic syndrome risk factors, resting heart rate, physical fitness, and arterial stiffness were measured and analyzed before and after initiation of the exercise program to determine the effect of exercise. Arterial stiffness was assessed based on brachial-ankle pulse wave velocity (ba-PWV). [Results] Compared to the control group; The metabolic syndrome risk factors (weight, % body fat, waist circumference, systolic blood pressure, diastolic blood pressure, and HDL-Cholesterol) were significantly improved in the exercise: resting heart rate was significantly decreased; VO2max, muscle strength and muscle endurance were significantly increased; and ba-PWV was significantly decreased. [Conclusion] Aerobic exercise had beneficial effects on the resting heart rate, physical fitness, and arterial stiffness of patients with metabolic syndrome.