Preadipocyte factor-1 is associated with marrow adiposity and bone mineral density in women with anorexia nervosa.
BACKGROUND
Despite having low visceral and sc fat depots, women with anorexia nervosa (AN) have elevated marrow fat mass, which is inversely associated with bone mineral density (BMD). Adipocytes and osteoblasts differentiate from a common progenitor cell, the human mesenchymal stem cell. Therefore, understanding factors that regulate this differentiation process may provide insight into bone loss in AN.


OBJECTIVE
The objective of the study was to investigate the relationship between preadipocyte factor-1 (Pref-1), a member of the epidermal growth factor-like family of proteins and regulator of adipocyte and osteoblast differentiation, and fat depots and BMD in AN.


METHODS
This was a cross-sectional study.


METHODS
The study was conducted at a clinical research center.


METHODS
Patients included 20 women with AN (26.8 +/- 1.5 yr) and 10 normal-weight controls (29.2 +/- 1.7 yr).


METHODS
There were no interventions.


METHODS
Pref-1, leptin, IGF-I, IGF binding protein (IGF-BP)-2 and estradiol levels were measured. BMD of the spine and hip was measured by dual-energy x-ray absorptiometry. Marrow fat content of the L4 vertebra and femur was measured by (1)H-magnetic resonance spectroscopy.


RESULTS
Pref-1 levels were significantly higher in AN compared with controls (P = 0.01). There was a positive correlation between Pref-1 and marrow fat of the proximal femoral metaphysis (R = 0.50, P = 0.01) and an inverse association between leptin and L4 marrow fat (R = -0.45, P < 0.05). There was an inverse association between Pref-1 and BMD of both the anteroposterior spine and lateral spine (R = -0.54, P = 0.003; R = -0.44, P = 0.02, respectively).


CONCLUSIONS
Pref-1 is elevated in AN. Pref-1, IGF-I, IGF-BP2 and leptin are associated with marrow adiposity and BMD.
Neuroendocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114, USA.
Pouneh K
PK
Fazeli
Miriam A
MA
Bredella
Madhusmita
M
Misra
Erinne
E
Meenaghan
Clifford J
CJ
Rosen
David R
DR
Clemmons
Anne
A
Breggia
Karen K
KK
Miller
Anne
A
Klibanski
D050154:Adiposity / Q000502:physiology*; D000328:Adult; D000856:Anorexia Nervosa / Q000097:blood* / Q000503:physiopathology*; D015519:Bone Density / Q000502:physiology*; D001853:Bone Marrow / Q000378:metabolism / Q000502:physiology*; D002135:Calcium-Binding Proteins; D016022:Case-Control Studies; D004958:Estradiol / Q000097:blood; D005260:Female; D006801:Humans; D018971:Insulin-Like Growth Factor Binding Protein 2 / Q000097:blood; D007334:Insulin-Like Growth Factor I / Q000032:analysis; D036341:Intercellular Signaling Peptides and Proteins / Q000097:blood*; D020738:Leptin / Q000097:blood; D008565:Membrane Proteins / Q000097:blood*; D055815:Young Adult
D002135:Calcium-Binding Proteins; C512941:DLK1 protein, human; D018971:Insulin-Like Growth Factor Binding Protein 2; D036341:Intercellular Signaling Peptides and Proteins; D020738:Leptin; D008565:Membrane Proteins; D004958:Estradiol; D007334:Insulin-Like Growth Factor I