By Talia Beechick
Ever feel like your alarm clock is going off far too early and that it couldn’t possibly be time to get out of bed and start your day? Ever think that the problem may lie within a different clock entirely. Say, your biological clock? According to Science Daily, scientists at the Salk Institute for Biological Studies in California have recently discovered the important role two nuclear receptors play in regulating sleeping and eating cycles as well as the development of our metabolism.
Link between our circadian rhythm and metabolism
First published in March, the study led by Ronald M. Evans, professor at the Salk Institute, implies a strong connection between our circadian rhythm, which is a biological, self-sustained process that takes place in 24-hour cycles, and our metabolism. This suggests new and different ways of treating associated disorders, such as jet lag, sleep disorders, diabetes and obesity.
Due to previous research, scientists have believed that two genes regulate and manipulate the master clock in our brains which determines both our sleeping and eating cycles. The master clock is set by light, determines our sleep-wake cycles and our feeding behavior as well as is found in all mammals. The master clock is also assisted by other, subsidiary clocks found in many of our other organs. The genes which control most of the master clock’s activity, known as BMAL1 and CLOCK, collaborate to activate the circadian genes, allowing us to wake up each morning alert, hungry and ready to be physically active, according to Science Daily.
Research reveals new role of cellular receptors, REV-ERB-α and REV-ERB-β
The Salk Institute’s latest study has unearthed a major gear within our biological clock whose significant role in our bodily rhythms has remained unknown until now. This gear is comprised of two cellular receptors—proteins which sense hormones and work with other proteins in order to control the body’s development and metabolism through the regulation of genes. These cellular receptors, or switches, are known as REV-ERB-α and REV-ERB-β and are essential to regulate normal sleeping and eating cycles as well as the metabolism of nutrients from the food we consume. Medical Xpress claims that because of the lack of research concerning these receptors, REV-ERB-α and β were previously thought to only have minor roles within our circadian rhythm. Scientists speculated that they worked with the BMAL1 and CLOCK genes in order to slow down our rhythms to maintain a steadiness and constancy throughout our bodily routines. This new study, however, shows the larger role the receptors play within our biological clocks.
Science Daily states that researchers at the Salk Institute were able to more closely observe and analyze the role of the REV-ERB-α and β receptors through mice in which these receptors, along with the BMAL1 and CLOCK genes, can be shut off using tamoxifen, an estrogen derivative usually associated with breast cancer therapy. The scientists shut the receptors off in the liver of the mice, an organ which plays a crucial role in maintaining balanced sugar and fat levels in the bloodstream, in order to see the effects on our bodily rhythms and processes.
How the receptors interact with the genes, BMAL1 and CLOCK
The scientists claim that the biological clocks of the mice “went haywire,” according to a Salk Institute news release. If this wasn’t evidence enough, upon further research the scientists found that the REV-ERBs controlled hundreds of the same genes regulated by BMAL1 and CLOCK, increasing their importance within these processes. This suggests that the REV-ERBs act as a break to slow clock activity. Scientists at the institute claim that the accelerator, BMAL1 and CLOCK, and the break play equally important parts in our circadian rhythm. Without REV-ERB-α and β receptors, therefore, our clocks cannot run properly, causing us to be active and hungry at incorrect times.
“This fundamentally changes our knowledge about the workings of the circadian clock and how it orchestrates our sleep-wake cycles, when we eat and even the times our bodies metabolize nutrients,” Evans said in a Salk Institute news release. “Nuclear receptors can be targeted with drugs, which suggests we might be able to target REV-ERB-α and β to treat disorders of sleep and metabolism.”
New findings can help treat sleep and metabolic disorders
Their discoveries, as stated by Evans, do not only affect treatment of disordered sleeping patterns. Scientists at the institute also observed that the REV-ERBs control hundreds of genes which are associated with our metabolism. For example, some of the genes regulate our levels of fats and bile. The mice in which the receptors were shut off had high levels of sugar and fat in their blood, two components found in people with metabolic disorders. These results imply a direct relationship between cellular metabolism and the REV-ERB receptors which will allow scientists to develop new ways of controlling and treating metabolic rhythms which are disrupted due to travel, work shifts or sleeping disorders. Because nuclear receptors are able to be targeted with drugs, Evans and his team are hoping to directly target the REV-ERBs as a new way to treat sleep and metabolic disorders, according to Medical Xpress.
Science Daily states that those who work shifts which alter the typical 24-hour cycle of waking and sleeping, such as nurses and emergency personnel, are at a higher risk for many of these disorders, including diabetes. This has spurred a host of studies which involve the composition of our biological clocks and ways to target specific controls within the clocks in order to alter the bodily rhythms of those who struggle with circadian disorders.
Our biological clock vs. our social clock
One such study, according to Science Daily, was released in May and discusses the negative impacts of the growing discrepancy between our biological and social clocks. Led by Till Roenneberg at the University of Munich, the study states that due to this “social jetlag,” as they termed it, people are more likely to be chronically sleep-deprived and are more likely to smoke and consume alcohol and caffeine. Scientists at the university also found that listening to our social clocks more than our biological ones contributes to obesity. Scientists are working to develop a world sleep map which includes participant’s height, weight and sleep patterns. So far, they have discovered that those with irregular sleeping patterns or higher rates of social jetlag are more likely to be overweight. The scientists are hoping the findings will eventually impact work and school start and end times as well as daylight saving time.
Listen to what your biological clock is saying to you. It might be saying you need to slow down the pace of your schedule or stay in on the weekend to catch up on some sleep. Science Daily reveals that scientists urge us, above all, to take care of ourselves through listening to our bodies and attempting to maintain a consistent routine when it comes to eating and sleeping cycles. It might be just the rhythm we need to be ready for that alarm clock in the morning.