Tick-Tock, Tick-Tock. Understanding your food clock!

food-clock 2If the excesses of holiday eating have sent your system into butter-slathered, alcohol-soaked overload, you are not alone. People with jet-lag, those who work graveyard and 24 hour shifts and even late-night snackers know just how you feel.

Turns out that all these activities upset the body’s “food clock”  – a collection of interacting genes and molecules which keep the human body on a metabolically even keel. Look behind the face of a mechanical clock and you will see a dizzying array of cogs, flywheels, counterbalances and other moving parts.

Biological clocks are equally complex, composed of multiple interacting genes that turn on or off in an orchestrated way to keep time during the day. In most organisms, biological clockworks are governed by a master clock, referred to as the ‘circadian oscillator,’ which keeps track of time and coordinates our biological processes with the rhythm of a 24-hour cycle of day and night.

Scientists also know that in addition to the master clock, our bodies have other clocks operating in parallel throughout the day. food clock 1One of these is the food clock, which is not tied to one specific spot in the brain but rather multiple sites throughout the body. The food clock is there to help our bodies make the most of our nutritional intake. It controls genes that help in everything from the absorption of nutrients to their dispersal through the bloodstream. It’s also designed to anticipate our eating patterns. Even before a meal, our bodies begin to turn on some of these genes and turn off others, preparing for the burst of sustenance – which is why we feel the pangs of hunger just before our lunch hour.

And while scientists have known that the food clock can be reset over time if a person changes their eating patterns, very little was known about how the food clock works on a genetic level.

Until now!  A new study by researchers at the University of California, San Francisco published in Proceedings of the National Academy of Sciences, is helping to reveal how this clock works on a molecular level. The study showed that normal laboratory mice given food only during their regular sleeping hours will adjust their food clock over time and begin to wake up from their slumber, and run around in anticipation of their new mealtime. But mice lacking a certain gene (PKCγ) are not able to respond to changes in their meal time and instead sleep right through it.

The work has implications for understanding diabetes, obesity and other metabolic syndromes because a desynchronized food clock may serve as part of the pathology underlying these disorders.

food_clock_3It may also help explain why night owls are more likely to be obese than morning larks,” says Louis Ptacek, MD, Distinguished Professor of Neurology at UCSF. “Understanding the molecular mechanism of how eating at the “wrong” time of the day desynchronizes the clocks in our body can facilitate the development of better treatments for disorders associated with night-eating syndrome, shift work and jet lag.”

All of which is potentially good news for this sleep-deprived, word-traveler, up-all-night-on-the-ambulance, always-on-a-diet blogger! SRxA-logo for web

Tick-tock, tick-tock…we’ll explain your biological clock!

If, like me, you’re one of those people who wake up at exactly the same time every morning without ever setting an alarm clock you’ve no doubt had people ask how you do it? Well, now you can tell them!

According to researchers at the Salk Institute for Biological Studies it’s all in our genes.  Recently they identified a gene responsible for starting our biological clock every morning.

The biological clock ramps up our metabolism early each day, initiating important physiological functions that tell our bodies that it’s time to rise and shine. Discovery of this new gene and the mechanism by which it starts the clock everyday may help explain the genetic underpinnings of sleeplessness, aging, and chronic illnesses such as cancer and diabetes.  Better still, it could eventually lead to new therapies for these illnesses.

The body is essentially a collection of clocks,” says Satchidananda Panda, an associate professor in Salk’s Regulatory Biology Laboratory, who led the research along with Luciano DiTacchio, a post-doctoral research associate. “We roughly knew what mechanism told the clock to wind down at night, but we didn’t know what activated us again in the morning. Now that we’ve found it, we can explore more deeply how our biological clocks malfunction as we get older and develop chronic illness.”

In a report just published in Science, the Salk researchers and their collaborators at McGill University and Albert Einstein College of Medicine describe how the gene encodes a protein that serves as an activation switch in the biochemical circuit that maintains our circadian rhythm. The discovery fills in a missing link in the molecular mechanisms that control our daily wake-sleep cycle.

It turns out that the molecular bugle call for cells and organs to get back to work each morning is an enzyme known as JARID1a.

Now that scientists understand why we wake each day, they can explore the role of JARID1a in sleep disorders and chronic diseases, possibly using it as a target for new drugs.

SRxA’s Word on Health looks forward to these developments and to a good night’s sleep!