He and his colleagues compared genes expressed in the cerebellum the area of the brain that controls posture, balance and muscle movement of adult and aged mice.
"A number of elderly people die each year from injuries related to falling," Rotter said. "Falling down implies a loss of both motor control and sense of balance, properties that are both associated with the cerebellum. We think there may be specific genes involved in this loss of function."
While the researchers are just beginning to uncover the differences between genes expressed in the cerebella of young and old mice, they're surprised with what they've found so far.
For instance, they found sizable decreases in the expression of genes that produce growth hormone, which is key to growth and development, and in prolactin, a hormone that stimulates milk production and also helps maintain the immune system. Growth hormone gene expression was nearly 10 times higher in the young mouse cerebellum, while prolactin gene expression was nearly 15 times higher in young mice.
"We don't know what role either hormone plays in the cerebellum, but the fact that there was such a drastic decrease in the hormones between the young and old mice means they represent genes that should be studied further," Rotter said.
The researchers presented their results on November 9 in New Orleans at the annual Society for Neuroscience meeting.
They analyzed gene expression in the mouse cerebellum using serial analysis of gene expression (SAGE), a powerful tool that lets researchers count the number of times a gene tag,
Contact: Andrej Rotter
Ohio State University