The 19th century German philosopher, Arthur Schopenhauer, once said of sleep:
Sleep is the interest we have to pay on the capital which is called in at death; and the higher the rate of interest and the more regularly it is paid, the further the date of redemption is postponed.Hyperbole? Maybe. But we have all experienced physical as well as emotional distress from disrupted sleep caused by frequent jet lags or late night work schedules.
Data from a new study in the Proceedings of the National Academy of Sciences now provides molecular insights into the impact on gene expression profiles of people, whose sleep is delayed by 4 hours for 3 consecutive days.
The researchers subjected 22 healthy volunteers, 11 males, 11 females, to a consistent sleep-wake routine for 28 days to evaluate the changes in gene expression profile from sleep delay, when compared to baseline. The gene expressions were studied using microarray technology with RNA samples extracted from volunteer blood samples.
When compared to baseline, delays in sleep caused a six-fold reduction of circadian rhythm-related gene expression in the blood samples tested.
The genes affected were involved in imperative functions such as “blood cell development and function, vascular function, immunity, and lipid metabolism.” Moreover, previous work from the same group shows that there is a significant decrease in the circadian rhythm-related gene expression in blood with just one week of insufficient sleep.
The increase in people suffering from jet lags, as well as working shift jobs necessitates the investigation of how our health is impacted by sleep delay and deprivation. This study provides a molecular basis for understanding the adverse effects of these on the human health, and perhaps even longevity. After all, Schopenhauer might just be right.