Relationship between autonomic nervous system activity during sleep and fasting glucose in Japanese workers

Effect of chlorogenic acids on fatigue and sleep in healthy males: A randomized, double-blind, placebo-controlled, crossover study

Chlorogenic acids (CGAs) are found in abundance in coffee beans and have numerous health benefits. This study investigated the effect of CGAs extracted from coffee beans on fatigue and sleep in healthy participants. This crossover study involved 16 men (aged 30-54 years) who were daytime workers with weekends off work. The participants were randomized into two groups: One group was given a placebo beverage, and the other was given an active beverage containing 300 mg of CGAs. The test beverages were consumed for 13 days starting on a Sunday. The evaluation criteria were feelings of fatigue and sleep quality, sleep-related indices recorded by an activity meter, and biomarkers. Feelings of fatigue and sleep-related indices during the first (first half of week 1) and second (second half of week 2) halves of the consumption periods were compared. Within the first half of week 1, no differences in feelings of fatigue were observed between the groups. However, during the second half of week 2, fatigue upon awakening and sleep quality in the active group were significantly improved compared with those in the placebo group. Sleep efficiency and total nocturnal awakening time were significantly deteriorated in the second half of week 2 compared with the first half of week 1 in the placebo group. Furthermore, significant differences in these indices were observed between the two groups in the second half of week 2. These results suggest that the daily consumption of CGA-containing beverages may improve fatigue upon awakening and sleep quality.

Decreased plasma brain-derived neurotrophic factor and vascular endothelial growth factor concentrations during military training

Decreased concentrations of plasma brain-derived neurotrophic factor (BDNF) and serum BDNF have been proposed to be a state marker of depression and a biological indicator of loaded psychosocial stress. Stress evaluations of participants in military mission are critically important and appropriate objective biological parameters that evaluate stress are needed. In military circumstances, there are several problems to adopt plasma BDNF concentration as a stress biomarker. First, in addition to psychosocial stress, military missions inevitably involve physical exercise that increases plasma BDNF concentrations. Second, most participants in the mission do not have adequate quality or quantity of sleep, and sleep deprivation has also been reported to increase plasma BDNF concentration. We evaluated plasma BDNF concentrations in 52 participants on a 9-week military mission. The present study revealed that plasma BDNF concentration significantly decreased despite elevated serum enzymes that escaped from muscle and decreased quantity and quality of sleep, as detected by a wearable watch-type sensor. In addition, we observed a significant decrease in plasma vascular endothelial growth factor (VEGF) during the mission. VEGF is also neurotrophic and its expression in the brain has been reported to be up-regulated by antidepressive treatments and down-regulated by stress. This is the first report of decreased plasma VEGF concentrations by stress. We conclude that decreased plasma concentrations of neurotrophins can be candidates for mental stress indicators in actual stressful environments that include physical exercise and limited sleep.