In a recent study, scientists found a way to target proteins involved in the internal clock of mammals. This clock regulates our bodies’ circadian rhythm, which is responsible for maintaining sleep-wake cycles and other physiological functions, such as maintaining body temperature and blood pressure. Sometimes, however, this internal clock goes haywire, and this malfunction is associated with disorders such as metabolic disease, anxiety, mood irregularities, sleep disorders, and schizophrenia.
Special “clock proteins” are involved in a proper circadian rhythm. The study focused on one receptor protein in particular, REV-ERB. This protein regulates sleep and emotions in mice. In the study, scientists gave mice drugs that activated REV-ERB. Using a variety of tests, they observed the drugs’ effects on their internal clocks and behavior.
Image Source: Kevin Liu
Researchers found that the mice given this drug exhibited increased wakefulness, decreased slow-wave and REM sleep, and decreased anxiety. In one test, for example, the mice were placed in cages with marbles and were assessed for marble-burying, a behavior associated with anxiety-like behavior. The mice given the drug displayed less of this behavior, burying half the marbles as the mice that were not given the drug. Mice that lacked the REV-ERB protein that were treated with the drug showed increased marble-burying behavior, providing support that it is the REV-ERB protein that the drug interacts with. Another test showed that, compared with mice from the control group, mice given the drug exhibited increased social interaction with new mice.
The REV-ERB drug is different from other drugs that influence circadian rhythms. Many drugs that increase wakefulness, such as amphetamines, also increase anxiety. Drugs that decrease anxiety, such as benzodiazepines, often also decrease wakefulness. The REV-ERB drug is beneficial in that it avoids the negative side-effects that the other drugs exhibit.
Interestingly, another test showed a decrease in reward-seeking behavior (the reward in the study being cocaine) in the mice as well. This suggests that the REV-ERB drug may also help treat addiction, which is related to circadian rhythm.
These findings show potential for drugs that regulate the internal clock to treat a wide range of things, including sleep, anxiety disorders, and possibly even addiction as well.
Feature Image Source: anxious by Andrew //
