Fibroblast growth factor 21 (FGF21) and bone: is there a relationship in humans?
1Diabetes, Endocrinology, Obesity Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bldg 10, CRC, 10 Center Drive, Bethesda, MD, USA, pcylee@gmail.com.
Summary
Higher fibroblast growth factor 21 (FGF21) levels are linked to greater bone mineral density (BMD) in women, contrary to animal studies. This suggests FGF21 may play a role in increasing bone mass in women.
Area of Science:
- Endocrinology
- Bone Biology
- Metabolic Health
Background:
- Fibroblast growth factor 21 (FGF21) influences energy homeostasis and bone metabolism.
- Animal studies show FGF21 administration causes bone loss, despite improving insulin resistance.
- Human data on the relationship between FGF21 and bone mineral density (BMD) is lacking.
Purpose of the Study:
- To investigate the association between plasma FGF21 levels and BMD in healthy adults.
- To determine if FGF21's effect on bone differs between sexes.
Main Methods:
- Measured fasting plasma FGF21 levels using enzyme-linked immunosorbent assay.
- Assessed body composition and BMD using dual-energy X-ray absorptiometry.
Main Results:
- No significant difference in median plasma FGF21 levels between men and women.
- In women, FGF21 levels positively correlated with fat mass and BMD (total and spine).
- In men, no significant correlation was observed between FGF21 and BMD or body composition.
Conclusions:
- A strong positive association exists between plasma FGF21 levels and BMD in healthy women.
- The findings suggest that the bone loss observed in animal models with high FGF21 may not directly translate to humans.
- FGF21 may promote bone mass in women, potentially via paracrine mechanisms at the bone-adipose interface.
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