Science is Fun Fridays!

 

With regards to neurodegenerative diseases such as dementia, scientists believe that disrupted protein synthesis is a major hallmark of aging.  Through wear and tear they exhibit inflammation and infection, which can impair the protein production that mediates cellular function.  To prevent these cells from causing harm, an "integrated stress response" becomes activated which shuts down protein production entirely.

They believe as we age, the ISR may become too active, so they wanted to test if it could be inhibited and thus reboot protein production.

Aged mice were trained to escape from a water maze using a hidden platform.  Using spatial, working, and episodic memory makes this harder for older mice to complete.  When the mice were given the ISR inhibitor over a period of three days, their performance levels matched those of younger mice.

They were tested again in a constantly changing maze, and they again found that the older mice treated with the inhibitor were just as efficient as young mice. 

Researchers analyzed neurons in the hippocampus, an area which plays a crucial role in memory and has been strongly implicated in cognitive decline.  They found that after just three doses of the inhibitor, hippocampal neurons had become more electrically responsive and had also developed more dendritic spines, allowing for stronger connections.  They had essentially reverted back to a state of youth.

They also found that immune cells had regenerated.  In particular, T cells were found to release fewer inflammatory compounds, which alleviates one of the major pathways associated with Alzheimer's and other forms of dementia.

Study author Peter Walter says, "The data suggests that the aged brain has not permanently lost essential cognitive capacities, as was commonly assumed, but rather that these cognitive resources are still there but have been somehow blocked, trapped by a vicious cycle of cellular stress."

IFLScience