All the Clocks Are Ticking: Sleep Health and Metabolism

Exploring the bi-directional relationship between sleep and resilience in adolescence

OBJECTIVE

The study examined whether overall sleep quality and the sleep components comprising the Pittsburgh Sleep Quality Index (PSQI) have a bi-directional relationship with resilience among adolescents, after adjusting for sex, age, depression, and socioeconomic status, and investigated which sleep components have a stronger effect on resilience.

METHODS

A total of 1299 students (58% females; mean age, 15.79 years) participated at baseline, with 840 finishing all four study waves over the course of 24 months. Data were collected through questionnaires, including socio-demographics, the Pittsburgh Sleep Quality Index, Patient Health Questionnaire 9-item, and the Connor-Davidson Resilience Scale. Cross-lagged models were used to analyze the relationships between sleep and resilience.

RESULTS

Both daytime dysfunction and sleep disturbance had an independent bi-directional relationship with resilience. Higher resilience scores predicted overall better sleep quality and shorter sleep latency, but not vice versa. Sleep disturbance and daytime dysfunction had stronger effects on resilience.

CONCLUSIONS

These findings highlight the importance of future school interventions for sleep to improve students' resilience.

Sedative and Hypnotic Effects and Transcriptome Analysis of Polygala tenuifolia in Aged Insomnia Rats

OBJECTIVE

To study the sedative and hypnotic effects and underlying mechanisms of Polygala tenuifolia (PT) on treating aged insomnia rats.

METHODS

Sixty Sprague-Dawley male rats were divided into 6 groups by a random number table, including control group, model group, diazepam group (0.92 mg/kg), as well as PT low-, medium- and high-dose groups (0.0875, 0.175, 0.35 g/kg, respectively), 10 rats in each group. Aged insomnia rat model was established with subcutaneous injection of D-galactose for 42 days and then intraperitoneal injection of para-chlorophenylalanine for 3 days. PT and diazepam were respectively given to aged insomnia rats by intragastric administration for 7 days after model establishment. Then the rats were investigated by body weight, Morris water maze test, pentobarbital test, enzyme-linked immunosorbent assay, and transcriptome sequencing.

RESULTS

Compared with the model group, PT increased the body weight, improved memory ability, and prolonged pentobarbital-induced sleep time of aged insomnia rats (P<0.01 or P<0.05). The medium dose of PT also increased the neurotransmitter levels of 5-hydroxytryptamine (5-HT) and gamma-aminobutyric acid (GABA), and decreased the level of Glu in the hippocampus of aged insomnia rats (P<0.05 or P<0.01). Twenty-four differentially expressed genes (DEGs) were overlapped among model group, medium-dose PT group, and diazepam group in transcriptome analysis. Fuom and Pcp2 were down-regulated by the treatment of medium-dose PT (P<0.01 or P<0.05). The metabolic pathways of PT were relatively less than diazepam (91 vs. 104).

CONCLUSIONS

The sedative and hypnotic effects of PT in aged insomnia rats might be related to neuro, metabolism pathways, especially through GABAergic signaling pathway. It provided more effective herb choice for the treatment of senile insomnia.