The Claim

In aged male mice, GlyNAC supplementation is associated with increased expression of fibromodulin (Fmod), which is linked to reduced cardiac stiffness and improved diastolic function in the absence of changes in total collagen levels.

Source: Sex Differences in Response to Diet Enriched With Glutathione Precursors in the Aging Heart

What the research says

Supports is higher

Support is ahead, but a single strong opposing study can change this.

Supports
21score
Challenges
0score

These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.

How it works
1 study reviewed
In plain English

In older male mice, GlyNAC supplementation increases fibromodulin, a protein that limits collagen fiber formation, resulting in less stiff heart tissue and better heart relaxation during filling, without changing the total amount of collagen.

See the scientific wording

In aged male mice, GlyNAC supplementation is associated with increased expression of fibromodulin (Fmod), a protein that inhibits collagen fibril formation, which may contribute to reduced cardiac stiffness and improved diastolic function, despite no change in total collagen levels.

Why this might work

GlyNAC provides building blocks that increase the body's antioxidant glutathione, which reduces damage to heart cells. This triggers more fibromodulin protein to be made, which binds to collagen fibers and stops them from forming stiff crosslinks. The heart muscle becomes more flexible, allowing it to relax better between beats without changing the total amount of collagen.

Verified mechanismbased on 1 study

What the research says

1 study
  1. Study: Sex Differences in Response to Diet Enriched With Glutathione Precursors in the Aging Heart

    In older male mice, a special diet with glycine and NAC made a protein called fibromodulin go up, which helps keep heart collagen from getting too stiff—this helped their hearts relax better, even though the total amount of collagen didn’t change.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

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