The laboratory of Neural Development and Learning at University of Wyoming

Finding the Cause Can Lead to a Cure Epilepsy

Qian-Quan Sun, assistant professor of zoology and physiology and a researcher on the neuroscience center grant, is studying how neural circuits develop in the brain. These circuits carry information to and from the different parts of the brain and body.

When looking at brain tissue under a microscope, Sun says it is difficult to see neural pathways. So Sun infuses genetically engineered mice with fluorescent jellyfish proteins that make the neural pathways glow. “We breed these mice, and their offspring have color-enriched brains,” Sun says.

Sun says he sees similarities between neural growth in human and mouse brain development, though during differing lengths of time. He says a 17-day-old mouse’s neural development corresponds roughly to neural growth in a one- to two-month-old human. That comparison can be useful when projecting results of experiments with mice to possible outcomes in humans.

Sun has learned that the growth of neural pathways is regulated by genetic programming and is enhanced—or retarded—by experience or trauma. An experiment on how a mouse’s whiskers transmit information to the brain in early developmental stages proved this theory. Whiskers are a mouse’s apparatus for sensing touch and spatial perspective. Sun and researchers mapped each area of the brain corresponding to a specific whisker by determining which section of the brain lit up when the whisker was stimulated. After whiskers were cut, over time the corresponding neural pathways in the brain failed to light up. “When we removed the stimulus, we retarded growth. The genes that controlled growth were disrupted,” Sun says.

Disrupted neural growth could be the underlying cause of epilepsy, Sun postulates. When an area of the brain is disrupted, the site of the disruption later becomes a site for abnormal neural growth. And when abnormal neural pathways form, stimuli can cause neurons to misfire down the abnormal pathway in a chain reaction. The result can be epilepsy.

Sun says this research also has applications for head trauma patients. “Loud noises or concussive blasts can cause connections between cells to become disrupted. This can cause subtle changes in the individual that are not readily apparent when using medical diagnostic equipment.”

Sun’s research is a first step toward discovering what causes neuron changes in the brain, which can lead to disease. Knowing the cause can lead to methods of prevention. Sun says this is especially important for diseases like epilepsy, where only symptoms can be treated. There is no existing cure.

Researchers are also trying to determine what triggers the overreaction to stimuli in epilepsy. Flynn uses the analogy of a car: brakes inhibit the brain’s neural transmitters, and when they fail, it speeds out of control.

Read the article " Mysteries Inside Us" by Dina Horwedel on UWYO megazine.

Leah Selby receives EPSCORE Summer and Fall Research Fellowship Award

Leah Selby receives the EPSCoR summer research fellowship for 2006. Leah is a pre-med undergraduate student. She participates in a medically related research project in Dr Sun’s lab. This project deals with the biological basis for the Fragile-X mental retardation syndrome (FXS), which is the leading form of inherited mental retardation with incidence of 1:2000 in males and 1:4000 in females. Taking advantage of a mouse mutation for the Fragile X Syndrome, she studies cellular problems intrinsic to brain of the Fragile X mouse. This project will help to determine a correlation between onset of microstructural changes and onset of behavior deficit. This information will also help to develop novel therapeutic approaches for curing this disease (May 20th 2006). Links to Fragile-X research foundation.

Congratulations to Leah for winning the fall EPSCoR felloship again (October 1st, 2006)!

Congratulations to Leah for being accepted by University of Washinton, School of Medicine.