Effects of dehydroepiandrosterone on in vitro cultured osteoblasts and osteoprotegerin in rats / 中国组织工程研究

ABSTRACT

BACKGROUND: Dehydroepiandrosterone (DHEA) derived from adrenal cortex has an indirect bioeffect through differentiating into androgen or estrogen in the related peripheral tissues. OBJECTIVE: To verify the effects and mechanisms of DHEA on promoting osteoblasts (OBs) proliferation. DESIGN, TIME AND SETTING: The grouping controlled experiment was accomplished in Shanghai Sixth People's Hospital affiliated to Shanghai Jiao Tong University and Institute of Radiation Medicine, Fudan University from January 2006 to February 2007. MATERIALS Ten SD rats were recruited, 1 day old, regardless of gender. DHEA was the product of American Sigma Company. METHODS: Rat OBs were separated and cultured in vitro. First generation of OBs cultured in a varied concentrations of DHEA (1?10-5, 1?10-7 and 1?10-9 mmol/L) for 72 hours were set up as the experiment group, while those exposed to 1?10-8 mmol/L of estradiol culture were regarded as positive controls and blank control group was set up as well. MAIN OUTCOME MEASURES: The OBs were identified by cell morphology and alkaline phosphatase (ALP) dyeing. Light microscope and methyl thiazolyl tetrazolium assay were used to detect the growth and proliferation of OBs. The formation of mineralized nodus was examined by alizarin bordeaux stain. The concentrations of osteoprotegerin in DHEA culture solution were also measured by double antibody sandwich ABC-ELISA simultaneously. RESULTS: ①Identification of primarily cultured OBs showed ALP dyeing was positive.②Proliferation rate of OBs was increased in experiment groups compared with that of the blank control group, and the most significant increase occurred in the concentration of 1?10-7 mmol/L DHEA culture (P 0.05).③ALP activity in experiment groups was higher, especially in the group with the concentration of 1?10-7 mmol/L DHEA (P 0.05).④ALP activity of unitary cell population was higher in 1?10-9 mmol/L DHEA culture group than that in blank control group (P