Fruit Flies Could Hold Secrets to Traumatic Brian Injury, Researchers Say

This article has been updated to note a change. 

Fruit flies offer a much needed look into traumatic brain injury (TBI), according to researchers from the University of Wisconsin, Madison. In a new study published in the Proceedings of the National Academy of Sciences, the scientists describe a reproducible method of inflicting trauma on the insects so as to mimic the injuries and symptoms seen in human TBI.

Caused when the brain strikes the inside of the school, TBIs can be classified from "mild" to "severe" based on a person's symptoms. In the short term, the immediate effects of TBI include confusion, dizziness, headaches and vision problems. Over time, however, the impacts may lead to neurodegeneration and related symptoms, such as memory loss, severe depression and Alzheimer's-like dementia.

Despite there being an estimated 1.7 million TBIs annually in the United States and tens of billions of dollars in medical expenses and indirect costs, such as loss of productivity, little is known regarding the underlying medical causes.

"Unlike many important medical problems -- high blood pressure, cancer, diabetes, heart disease -- where we know something about the biology, we know almost nothing about TBI," geneticist and study author Barry Ganetzky said in a statement. "Why does a blow to the head cause epilepsy? Or how does it lead down the road to neurodegeneration? Nobody has answers to those questions -- in part, because it's really hard to study in humans."

To get around this, Ganetzky turned to fruit flies, which contain several key similarities to humans, including the equivalent of a skull and the same basic mechanisms affecting nervous system function. Like humans, flies rarely die from immediate impact, exhibiting similar short term effects, and appear to be more susceptible in their old age.

In the new study, Ganetzky and David Wassarman, a professor of cell and regenerative biology, outline a way to systematically inflict trauma on the flies to allow for consistent observation. In doing so, they hope to open the doors to increased research on the issue.

"Now we have a system where we can look at the variables that are the inputs into TBI and determine the relative contributions of each to the pathological outcomes," Wassarman explained. "That's the real power of the flies."