Researchers at Yale School of Medicine demonstrate that systemic cysteine depletion triggers sympathetic-driven browning of white adipose tissue, increasing energy expenditure and rapid weight loss. Using CTH knockout mice on cystine-free diets and integrated metabolomic, transcriptomic, and imaging analyses, they reveal an FGF21-linked, UCP1-independent thermogenic mechanism with potential metabolic health benefits.
Key points
- Cth knockout mice on cystine-free diets lose 25–30% body weight within six days due to fat loss.
- Adipose browning is driven by sympathetic noradrenaline and β3-adrenergic signaling, independent of UCP1.
- Metabolomics reveal glutathione and CoA depletion, GCLC/GSS upregulation, and elevated FGF21 supporting thermogenesis.
Why it matters: By revealing cysteine’s critical role in adipose thermogenesis, this study opens new avenues for metabolic and longevity therapies beyond classical UCP1 pathways.
Q&A
- What role does cysteine play in metabolism?
- How does adipose browning contribute to weight loss?
- What is a UCP1-independent thermogenic pathway?
- Why is FGF21 important in cysteine-depletion studies?