Sleep and Body Chemistry
Andrew Gall, Ph.D. | Assistant Professor of Psychology
Getting a good night’s rest isn’t always as easy as counting sheep. We might need to rethink our diets, too. Dr. Andrew Gall has investigated whether a high-fat diet may play a role in irregular sleep patterns, and based on lab results, he thinks the answer may be yes.
This 2018 research was part of the behavioral neuroscientist’s focus on sleep and circadian rhythms — physical cycles that are the body’s responses to light and darkness. Another of his 2018 projects related to sleep disturbances and neuropsychiatric illnesses such as bipolar disorder.
To explore food’s impact on circadian rhythms, Gall and students in his Hope College research group teamed up with Western Michigan University biomedical sciences professor Dr. Peter Vollbrecht to see whether lab rats’ sleep patterns would change if their diet did. For six weeks they fed plain rat chow to one group of Nile grass rats, but added cookies, potato chips and peanut butter to the chow a second group received. (Unlike most rats, Nile grass rats sleep at night, so they’re ideal for sleep research.) Infrared sensors on the animals’ cages showed that rats fed the high-fat diet became more active at night. Gall and his students presented their findings at the 2018 annual meeting of the Michigan Chapter of the Society for Neuroscience and at other conferences.
“I see this research as the first step in understanding some of the very basic mechanisms that underlie how sleep and circadian rhythms develop and how they get expressed,” Gall says. “One day, new research can extrapolate that to understanding human behavior.”
Gall also collaborates with Hope biochemist Dr. Leah Chase. Chase’s research has established that in rats, high levels of the natural compound homocysteic acid can cause manic and depressive behaviors that mimic the symptoms of bipolar disorder in humans. With support from a Nyenhuis grant from the college, in 2018 Gall explored how those bipolar-like behaviors affect sleep. The study found that rats displaying symptoms similar to human bipolar disorder had disrupted circadian rhythms — they woke up earlier each morning than a control group.
Gall and another group of students then tested whether lithium, a drug used to treat bipolar disorder in humans,would reverse those disrupted sleep patterns. They ground up lithium and rat chow and fed the doctored food to the rats in which bipolar symptoms had been induced, plus to a control group. Over four weeks, the experimental group’s sleep patterns became more similar to the control group’s. “We’re showing that circadian rhythms are being improved by lithium treatment, which is very exciting,” Gall says.