Ziv Zwighaft is a research student in the group of the Weizmann Institute’s Dr. Gad Asher. Their new findings reveal some intriguing connections between our circadian clocks – which tick according to cycles of day and night – metabolism and aging. Here is his description:
King Solomon said: “There is a time for everything, and a season for every activity under the heavens.”
Our research tries to take this insight into the condition of living creatures a few strides forward. How strictly does it apply? Our lives are regulated by a biological clock – it’s actually many clocks working in synergy, orchestrating our waking, sleeping and eating, our growth and life stages and, recent research suggests, our metabolism. So first and foremost, the new findings are strong support for the claim that our circadian clocks are strongly intertwined with our body’s metabolic activities. We showed that the daily changes in the levels of a group of essential metabolites called polyamines are regulated from two sides – both by eating times and by the ticking of the clock. Polyamines are naturally occurring metabolites that are known to play a role in various essential cellular processes, as well as pathologies. Our research shows that they also play an active role in setting the tempo of our internal timing. (The research revealed that polyamines both regulate and are regulated by a circadian clock. WSW)
Dysfunction in the clock can lead to a wide range of diseases, starting with sleep disorders and on to metabolic disorders like obesity and diabetes, and up to psychological illnesses.
One of the things I found most encouraging was our success in reproducing the results we obtained in tissue culture and raising them to the level of the whole animal. Here, a deviation from the natural polyamine levels translated into clock malfunction. For example, low levels of polyamines made the clock run slow, and this situation was reversible by enriching the diet with polyamines.
This phenomenon – a drop in polyamine levels and impairment in the clock’s accuracy – is typical of the process of aging. So by investigating the joins between two worlds – circadian clocks and metabolism – we able to demonstrate how to “rejuvenate” the internal pace of timekeeping in old mice.
This particular study is finished, but the work has not been completed. In these days we are continuing to look for additional connections between the circadian clocks and metabolic processes in the body; these connections may lead to new strategies in the war against age-related disease.
So bad news and good: On the one hand, polyamine levels of tend to drop as we age, and our internal clocks lose time. On the other hand, we get polyamines from food too. When the researchers added a polyamine supplement to the diets to old mice, their slow circadian clocks gained minutes.
Asher says that much more research will be needed before we can tell whether such food supplements will have an effect on aging in humans. In the meantime, however, it can’t hurt to stick to a healthy diet and add some extra edamame, peas or lentils to the menu.