RESUMO
Whole-body vibration (WBV) can decrease arterial stiffness, but the effects of low-frequency WBV on arterial stiffness are not known. The aim of this study was to clarify the acute effects on arterial stiffness of WBV by vibration frequency. This study involved 9 healthy men (age: 31 ± 7 years). Each WBV session involved 3 sets of 4 different vibrations (0 Hz [control], 12 Hz, 20 Hz, 30 Hz) lasting 60 s with a 60-s inter-session rest interval. During WBV, the participants adopted a static squat position with their knees bent. An automatic oscillometric device was used to measure brachial-ankle pulse wave velocity (baPWV) before (baseline) and 5, 15, and 30 min after WBV. There was a significant decrease in baPWV from baseline at 30 min (P = .02) after WBV at 30 Hz. However, there was no change in baPWV at any time points after WBV at 0 (control), 12, and 20 Hz. These results suggested that low-frequency WBV does not affect arterial stiffness.
Assuntos
Índice Tornozelo-Braço/métodos , Hipertensão/fisiopatologia , Análise de Onda de Pulso/métodos , Rigidez Vascular/fisiologia , Vibração/efeitos adversos , Adulto , Voluntários Saudáveis , Humanos , Masculino , Projetos de PesquisaRESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: The fruits of Schisandra chinensis (Trucz.) Baill. (Schisandraceae) which have been used as a tonic especially for kidney yin deficiency in Chinese traditional medicine are recently receiving attention for its preventive activity on age-related neurodegenerative diseases. A variety of studies demonstrated the cognitive-enhancing effects of Schisandra chinensis through animal tests and also in clinical trials. AIM OF STUDY: In this study, we attempted to investigate the effects of the lignan-riched extract of Schisandra chinensis fruits (ESP-806) on neurotoxicity and memory impairment induced by Aß1-42 injection in mice. MATERIALS AND METHODS: The fruits of Schisandra chinensis were extracted with the mixture of n-hexane:ethanol (9:1), which is riched with bioactive dibenzocyclooctadiene lignans, schizandrin, gomisin N, wuweigisu C. After oral treatment of ESP-806 (100 mg/kg body weight) followed by injection of Aß1-42 (2 µg/mouse, i.c.v.), novel object recognition and passive avoidance tests were evaluated. To verify the cognition enhancing effects of ESP-806, we examined the effects of ESP-806 on the activities of ß-secretase and acetylcholinesterase, and the contents of Aß and the reduced glutathione within the cortex and hippocampus of Aß-injected mice. RESULTS: Oral treatment of ESP-806 (100 mg/kg body weight) significantly attenuated Aß1-42-induced memory impairment evaluated by behavioral tests. Furthermore, the treatment of ESP-806 attenuated the elevation of ß-secretase activity accompanying the reduced level of Aß1-42 in the cortex and hippocampus of the brain. ESP-806 also significantly inhibited the acetylcholinesterase activity in the hippocampus and increased the content of the reduced glutathione in the cortex and hippocampus of mouse brain. CONCLUSIONS: These data suggested that the extract of Schisandra chinensis fruits riched with dibenzocyclooctadiene lignans may be useful in the prevention and treatment of Alzheimer's disease.