Sleep Deficiency in Obstructive Sleep Apnea

Recent Progress in Long-Term Sleep Monitoring Technology

Sleep is an essential physiological activity, accounting for about one-third of our lives, which significantly impacts our memory, mood, health, and children's growth. Especially after the COVID-19 epidemic, sleep health issues have attracted more attention. In recent years, with the development of wearable electronic devices, there have been more and more studies, products, or solutions related to sleep monitoring. Many mature technologies, such as polysomnography, have been applied to clinical practice. However, it is urgent to develop wearable or non-contacting electronic devices suitable for household continuous sleep monitoring. This paper first introduces the basic knowledge of sleep and the significance of sleep monitoring. Then, according to the types of physiological signals monitored, this paper describes the research progress of bioelectrical signals, biomechanical signals, and biochemical signals used for sleep monitoring. However, it is not ideal to monitor the sleep quality for the whole night based on only one signal. Therefore, this paper reviews the research on multi-signal monitoring and introduces systematic sleep monitoring schemes. Finally, a conclusion and discussion of sleep monitoring are presented to propose potential future directions and prospects for sleep monitoring.

Cx43 overexpression reduce the incidence of obstructive sleep apnea associated atrial fibrillation via the CaMKⅡγ/HIF-1 axis

BACKGROUND

Previous studies by our group have demonstrated chronic intermittent hypoxia (CIH) can decrease connexin 43 (Cx43) protein expression and thus increase atrial fibrillation (AF) inducibility. Cardiac sympathetic denervation (CSD) can reduce AF and increase Cx43 expression, however, the underlying molecular mechanisms and signaling pathways are still unclear.

METHODS AND RESULTS

An obstructive sleep apnea (OSA) rat model in vivo experiments and CIH H9c2 cells model in vitro experiments were used to figure out the roles and underlying mechanisms of Cx43 on OSA-associated AF. In this study, we examined the expression of Cx43, CaMKⅡγ, Bax, Caspase 3, HIF-1 Bcl-2, Tunel, and CPB/p300, to discover the association between proteins and the mechanism of regulatory changes. The downstream proteins of Cx43 were calculated by gene sequencing and data analysis. We found Cx43 expression was significantly downregulated after CIH exposure in rat and H9c2 cells. Active caspase-3 and Bax at CIH+8 h group are high, but decreased at OE+8 h group. The Bcl-2 expression was higher in the N and OE+8 h group than CIH+8 h group. TUNEL-positive cells from the CIH+8 h group was markedly higher. Furthermore, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses indicated Cx43 overexpression inhibited the CaMKIIγ expression, and CaMKIIγ was involved in the HIF-1 signaling pathway. In addition, we also found Cx43 overexpression remarkably decreased the HIF-1 protein and p300 mRNA expression, which inhibits the CaMKIIγ/HIF-1 signaling pathway.

CONCLUSIONS

Taken together, these results suggested Cx43 overexpression inhibits the expression of calcium/calmodulin dependent protein CaMKⅡγ via the Cx43/CaMKIIγ/HIF-1 axis, which finally reduces the myocardial apoptosis and incidence of AF.

Effects of One Night of Forced Wakefulness on Morning Resting Blood Pressure in Humans: The Role of Biological Sex and Weight Status

Permanent night shift work is associated with adverse health effects, including elevated blood pressure (BP) and hypertension. Here, we examined the BP response to one night of forced wakefulness in a sitting position in a cohort without night shift work experience. According to a counterbalanced crossover design, 47 young adults with either obesity (N = 22; 10 women) or normal weight (N = 25; 11 women) participated in one night of sleep and one night of forced wakefulness under in-laboratory conditions. Resting ankle and brachial arterial BP were assessed in the morning, i.e., the time of the day when adverse cardiovascular events peak. After forced wakefulness, diastolic and mean arterial BP were ~4 mmHg higher at the ankle site and ~3 mmHg higher at the brachial site than after regular sleep (p < 0.05). The increase in BP following overnight forced wakefulness was more pronounced among men vs. women and more significant for diastolic BP at both sites among participants with normal weight vs. those with obesity. If confirmed in larger cohorts, including 24 h BP monitoring, people with occupations involving night shifts might benefit from regular BP monitoring. Particular attention should be paid to possible sex- and weight-specific effects of night shift work on BP.