From wrinkles to worsening mobility to forgetfulness, our bodies show signs of aging in countless ways. But what about behaviors we take with us into old age that seem mostly aging-resistant? Why do some aspects of our brains show wear and tear, while others don’t? As further research leads to more discovery, biologists are studying aging and its impact on everyday functions, including motor skills and neurological function.
Researchers at the University of Iowa took part in a study observing the aging process of fruit flies. The team was interested in how older flies maintain their ability to perform motor functions necessary for survival — such as always being able to avoid a fly swatter.
Individual neurons and neural circuits of these fruit flies were analyzed for their ability to fly in various environmental conditions. During the trial, stressors were introduced such as temperature changes and breakdown of protective antioxidants in their bodies—regardless of age differences in the flies.
Researchers were able to uncover biomarkers of aging when analyzing specific motor circuits. Based on the data collected, the team was able to further examine which circuits weakened with age and which circuits remained the same.
Remarkably, the fruit fly’s ability to escape danger proved to be the same no matter the fly’s age. Aging-resilient circuits were observed when researchers noted the fruit fly’s awareness and reaction to a fly swatter. The results demonstrated that the reaction was the same regardless of where the fly was in its life-cycle. Therefore, age did not have a direct correlation to motor function.
In contrast, other functions were observed to have weakened with age, such as the fly’s muscle activity during flight. Fruit flies with advanced age were also shown to have seizures. Neural circuits tied to these functions were noticeably weakened and vulnerable.
“Our identification of aging ‘landmarks’ in motor circuit function will help future studies in uncovering genetic pathways or environmental factors contributing to healthy aging in the brain as well as age-related neurodegeneration,” says study co-author Atulya Iyengar, a post-doctoral researcher in the university’s Department of Biology and researcher with the Iowa Neuroscience Institute, in a statement.
Aging is a biological process of special interest to researchers. The ability to understand circuit function as it relates to motor skills will provide new and useful information on how genetics and the environment intersect. Researchers are hoping to learn more about aging and neural circuitry and the impact they have on neurodegenerative conditions.
Contributing authors for the research also include Chun-Fang Wu, professor in Iowa’s Department of Biology, and Hongu Ruan, a former professor at the University of Iowa and now assistant professor at SUNY Upstate Medical University.
This study is published in the journal eNeuro.