# Lab-grown human muscle mimics aging when exposed to blood from older people

Researchers developed human in vitro skeletal muscle models that replicate age-related muscle atrophy and reduced contractile function when treated with serum from aged individuals. This finding demonstrates that factors circulating in aged blood directly drive muscle decline, and provides a powerful new platform for studying muscle aging and testing potential therapies without animal models.

**Importance:** 4/5

## Sources

### Science
- [Nature](https://www.nature.com/articles/s41514-026-00472-9) — 2026-08-12