Relationship between serum level of growth differentiation factors 8, 11 and bone mineral density in girls with anorexia nervosa.

BACKGROUND: Adolescents with anorexia nervosa (AN) have low body mass and low bone mineral density (BMD). Growth differentiation factor 8 (Myostatin, GDF8) and its homologue growth differentiation factor 11 (GDF11), members of the TGF-ß super-family, play an important role in muscle regeneration and bone metabolism in healthy individuals. However, their association with BMD in AN is unknown. The present study was undertaken to investigate the relationship between GDF8, GDF11 and BMD in adolescent girls with AN. METHODS: Serum GDF8, GDF11 and BMD were determined in 25 girls (12-16 years old) with AN and 31 healthy girls (12-16 years old). RESULTS: Growth differentiation factor 8 levels were lower in AN subjects. On the contrary, GDF11 levels were higher in AN subjects than controls. There was no relationship between GDF8 and BMD. A significant negative correlation between GDF11 and BMD was found. In multiple linear stepwise regression analysis, BMI, 25-hydroxyvitamin D, GDF11, or lean mass, but not fat mass and GDF8, were independent predictors of BMD in the AN and control groups separately. CONCLUSIONS: Growth differentiation factor 11 was independent predictor of BMD in girls with AN. It suggested that GDF11 exerts a negative effect on bone mass.