Serum Preadipocyte Factor 1 Levels Are Not Associated with Bone Mineral Density among Healthy Postmenopausal Korean Women

BACKGROUND: Multipotent mesenchymal stem cells can differentiate into adipocytes or osteoblasts through closely regulated lineage-control processes. However, adipocyte precursor cells release preadipocyte factor 1 (Pref-1), which inhibits the differentiation of mesenchymal stem cells into mature adipocytes and osteoblasts. Previous studies have also reported an inverse association between Pref-1 levels and bone mineral density (BMD) among patients with anorexia nervosa. METHODS: In this retrospective study, we examined the correlations between Pref-1 levels and BMD among 124 healthy postmenopausal women (>50 years old). The patients had provided information regarding their clinical characteristics, and underwent blood testing and serum Pref-1 testing. RESULTS: The subjects' mean age was 59.9±7.1 years and the median time since menopause onset was 9.1 years. A history of osteoporotic fracture was identified in 23 subjects (19%). Serum Pref-1 levels were not significantly correlated with BMD values at the lumbar spine (R²=0.038, P=0.109), femur neck (R²=0.017, P=0.869), and total hip (R²=0.041, P=0.09), and multivariate analyses with adjustment for age and body mass index also did not detect any significant correlations. Subgroup analyses according to a history of fracture also did not detect significant associations between Pref-1 levels and BMD values. CONCLUSION: In our study population, it does not appear that serum Pref-1 levels are significantly associated with BMD values and osteoporosis.

Expression of Preadipocyte Factor-1 (Pref-1) and Vitamin D3 Up-regulated Protein 1 (VDUP1) Genes in Rat Adrenal Gland following Chronic Immobilization Stress / 대한해부학회지

Preadipocyte factor-1 (Pref-1) is expressed in the neuroendocrine organs such as the pituitary gland, the adrenal gland, the pancreas, the testis, etc. Vitamin D3 up-regulated protein 1(VDUP1) gene is known to be a novel member of early response genes as an oxidative stress mediator. The aim of the present study was to investigate whether Pref-1 and VDUP1 is involved in stress response in the adrenal gland following chronic immobilization stress. In situ hybridization for Pref-1 and VDUP1 genes (Pref-1 and VDUP1) was performed in the rat adrenal glands following immobilization stress, 2 hr once daily for 7 days. In situ hybridization analysis revealed that Pref-1 expression was up-regulated in rat adrenal medulla following chronic immobilization stress. However, Pref-1 was down-regulated in the zona glomerulosa of the adrenal cortex following chronic immobilization stress. VDUP1 expression was up-regulated in the zona glomerulosa and the adrenal medulla following chronic immobilization stress. These results show that Pref-1 and VDUP1 may be novel genes responding to chronic immobilization stress in adrenal gland.