Somewhat related... I also saw this study, recently. Also in mice...

This study finds that naturally-occurring ACD (Age associated Cognitive Decline) is associated with multiple abnormalities in the brain, and provides proof-of-concept that GlyNAC (glycine and N-acetylcysteine) supplementation corrects these defects and improves cognitive function in aging.

I came across it from here, and that author added:

Glycine is a cheap and safe supplement which you may take right now. NAC is also available as a supplement.