Old and Sleepy
In college I could sleep like a champ. Staying up way past midnight and then snoozing till noon on weekends was routine. Alas, senior year physical chemistry at 8 a.m. five days a week prevented such lifestyle luxury on school days.
This slumber pattern has changed as I’ve gotten older. Nowadays, heeding Ben Franklin’s advice, I go to bed early and get up well before dawn. My daughter even teases me about it—says I’m missing all the good TV shows. Truth be told, I probably wouldn’t watch even if I stayed up.
Naturally, pondering changes in life’s basic temporal rhythms causes me to wonder if some fundamental chemistry lies underneath. New research from collaborating Swiss institutions offers some hints (Proceedings of the National Academy of Sciences of the United States of America, published ahead of print, April 11, 2011).
Using human skin cells, Pagani et al. show that the basic clock, timing, and phase properties are the same in both young and old subjects. However, when serum from elderly folks was placed on the cells of younger ones, the period length shortened, and the phase of the clock shifted. In plainer English, the cells sleep more and go to bed earlier (assuming cells do such things).
So something in the circulation affects the basic timing of cells. A clue about what that something is lies in the observation that heat inactivates the effect, suggesting a protein or unstable metabolite might be a key regulator of sleep cycles.
We don’t yet know the chemical identity of the sleepy substance, but the authors speculate that further research might offer pharmacological remediation of age-related sleep patterns. Gee, maybe now I’ll be able to stay up to watch all those good TV shows and still get up early enough to enjoy the sunrise.