Mental and physical exercise improves genetic mental impairment

Australian scientists have shown that mental and physical exercise can improve coordination and movement problems in Rett syndrome, a devastating genetic brain development disorder that primarily affects females. Using a mouse model of Rett syndrome developed by the Children's Medical Research Institute in Sydney, researchers from the Howard Florey Institute in Melbourne found these mice responded positively to the effects of environmental enrichment.

A/Prof Anthony Hannan from the Howard Florey Institute said the onset and severity of coordination and movement problems was reduced by giving the Rett syndrome mice a range of mazes, toys and exercise equipment to stimulate them both mentally and physically.

"Mari Kondo in my laboratory discovered that environmental enrichment significantly improved the ability of the Rett syndrome mice to learn and maintain tasks that required coordinated movements," A/Prof Hannan said.

"We also found that a special brain chemical called BDNF, which plays a role in the birth and survival of new neurons as well as modifying connections in the brain, was at similar levels in both normal mice and the enriched Rett syndrome mice.

"The Rett syndrome mice that did not receive environmental enrichment had lower levels of BDNF and performed poorly on movement and coordination tasks.

"This discovery shows that gene-environment interactions may be important for all brain diseases, including those caused by an inherited gene mutation.

"The next step is for us to look at the effects of environmental enrichment on anxiety and cognition in the mice, as these are common problems in Rett syndrome," he said.

Developer of the Rett syndrome mouse model, Prof Patrick Tam of the Children's Medical Research Institute, said for the past seven years his research team, and especially Dr Gregory Pelka, had been investigating Rett syndrome genetics.

"We have already found a number of genes that may be linked to the development of Rett syndrome," Prof Tam said.

"More research in this area is urgently needed as Rett syndrome is the second most common form of severe mental disability in girls after Down syndrome in Australia," Prof Tam added.

Source: Research Australia