Summary of earlier studies
How a body chemical called NAD+ may relate to Parkinson's disease
This review summarizes earlier work on NAD+, a chemical that helps cells make energy. Its levels fall with age and are lower in the brains of people with Parkinson's.
Animals
Immune cells in aging bone marrow and how they affect bone loss in mice
Researchers found a signal in bone marrow immune cells that links fat buildup to weaker bone formation. Blocking it with NMN in mice reduced bone loss, but this does not show the same happens in people.
People
Trained older adults showed muscle changes that looked more like those of younger adults
Researchers studied muscle from younger and older people, some fit and some less fit, before and after one bout of exercise. Half of the age-related muscle differences were missing in trained older adults.