This study investigated the effects of sleep deprivation on heart rate variability (HRV), blood pressure (BP), fasting blood glucose (FBG), and endothelial function as well as the immediate effects of 4‐7‐8 breathing control on HRV and BP. In total, 43 healthy participants aged 19–25 years were classified into two groups: Twenty two in the with sleep deprivation group and 21 in the without sleep deprivation (control) group. Resting heart rate (HR), BP, HRV, FBG, and endothelial function were examined. Subsequently, participants practiced 4‐7‐8 breathing control for six cycles/set for three sets interspersed between each set by 1‐min normal breathing. Thereafter, the HR, BP, and HRV were immediately examined. The HRV, HR, and BP variables and FBG were not significantly different between the two groups. However, endothelial function was significantly lower in the sleep deprivation group than that in the control group (p < 0.05). In response to 4‐7‐8 breathing control, low‐ and very‐low‐frequency powers significantly decreased (p < 0.05), whereas high‐frequency power significantly increased (p < 0.05) in the control group. Moreover, time domain, total power, and very‐low‐frequency power significantly decreased (p < 0.05) in the sleep deprivation group. Both groups had significantly decreased HR and systolic BP (p < 0.05). HRV, HR, and BP variables showed no significant differences between the groups. Healthy young adults with and without sleep deprivation may have similar HRV, BP, and FBG values. However, sleep deprivation may cause decreased endothelial function. Furthermore, 4‐7‐8 breathing control can help participants improve their HRV and BP, particularly in those without sleep deprivation.

We investigated the changes in the oxidative stress and cardiovascular disease risk biomarkers, including the activity of the cardiac autonomic nervous system, in older adults with prehypertension following Riceberry rice bran oil supplementation. A total of 35 women aged 60 to 76 years with prehypertension were randomly allocated to two groups, one of which was supplemented with rice bran oil (n=18) and the other with Riceberry rice bran oil (n=17) at 1,000 mg daily for 8 weeks. Prior to and after the supplementation, oxidative stress and cardiovascular risk biomarkers (primary outcomes), heart rate variability, and blood pressure (secondary outcomes) were investigated. Results showed that plasma malondialdehyde, blood glutathione disulfide, and tumor necrosis factor-alpha levels were significantly decreased, and the ratio of reduced glutathione to glutathione disulfide significantly increased in both groups after supplementation (all P<0.05). No significant differences were observed between groups. Heart rate variability and blood pressure did not statistically significantly change subsequent to supplementation in either group and did not differ between groups. In conclusion, Riceberry rice bran oil supplementation for 8 weeks alleviates oxidative stress and inflammation in older adults with prehypertension to a similar extent as rice bran oil supplementation.

Background In this study, we aimed to measure the changes in the biomarkers of oxidative stress, cardiovascular disease risk, and the activity of the cardiac autonomic nervous system in older adults with prehypertension after supplementation with Riceberry rice bran oil. Methods In total, 35 women aged 60–76 years with prehypertension were randomly allocated to two groups, one of which was supplemented with rice bran oil (n = 18) and the other with Riceberry rice bran oil (n = 17) at 1,000 mg (500 mg × 2 capsules) daily for 8 weeks. The primary outcomes, including oxidative stress and cardiovascular risk biomarkers, and secondary outcomes, including heart rate variability and blood pressure, were determined before and after the 8-week supplementation. Results The levels of plasma malondialdehyde, blood glutathione disulfide, and tumor necrosis factor-alpha were significantly decreased, and the ratio of reduced glutathione to glutathione disulfide significantly increased in both groups after supplementation (all p < 0.05). No significant differences were noted between groups. Heart rate variability and blood pressure were not statistically significantly different after supplementation in both groups. Conclusions Supplementation with Riceberry rice bran oil for 8 weeks may attenuate oxidative stress and inflammation in older adults with prehypertension. The effects of a longer supplementation period or use in hypertensive persons should be further investigated, especially with regard to blood pressure and cardiac autonomic nervous system activity. Trial registration: This trial was registered March 22, 2019 at https://www.thaiclinicaltrials.org as TCTR20190322002.