acid-phosphatase and 8-prenylnaringenin

This study is to investigate the effect of 8-prenylnaringenin (8-PNG) on osteoclastogensis of bone marrow cells and bone resorption activity of osteoclasts. Osteoclasts were separated from long bone marrow of newborn rabbits and cultured in alpha-MEM containing 10% FBS. 8-PNG was added into culture media at 1 x 10(-7), 1 x 10(-6), 1 x 10(-5) mol xL(-1), separately. 17beta-Estradiol (E2, 1 x 10(-7) mol x L(-7)) was used as positive control. T RAP staining and TRAP activity measurement were performed after 5 days, and the bone resorption pits were analyzed after 7 days. Annexin V staining for the detection of apoptotic osteoclasts was performed after 2, 4, 8, 12, 24, 36 and 48 h separately. The mRNA expression level of TRAP and cathepsin K (CTSK) was measured by real-time RT-PCR. 8-PNG significantly reduced the number of osteoclasts which was TRAP staining positive and with more than three nucleus, the area and number of bone resorption pits decreased obviously in 8-PNG-supplemented groups. The apoptosis rate peaked earlier in the 8-PNG-supplemented groups and the mRNA expression level of TRAP and CTSK decreased significantly. All these inhibitory effects were in a dose dependent manner, the highest effect was obtained by 1 x 10(-5) mol x L(-1) 8-PNG. 8-PNG inhibits bone resorption activity of osteoclasts by inducing osteoclast apoptosis and inhibiting the gene expression and enzyme activity including TRAP and CTSK, and restrains bone marrow cells to osteoclast differentiation.

Topics: Acid Phosphatase; Animals; Apoptosis; Bone Marrow Cells; Bone Resorption; Cathepsin K; Cells, Cultured; Dose-Response Relationship, Drug; Flavanones; Isoenzymes; Osteoclasts; Rabbits; RNA, Messenger; Tartrate-Resistant Acid Phosphatase

To compare the effects of 8-prenylnaringenin (PNG) and naringenin (NG) on the activity and apoptosis of osteoclasts cultured in vitro, in order to study physiological activity of 8-prenyl perssad.. Osteoclasts were separated from long-limb bones of newly born rabbits, cultured in alpha-MEM containing 10% FBS, and then added with PNG and NG with the concentration of 1 x 10(-5) mol x L(-1). They were stained with TRAP and determined for enzymatic activity with TRAP after 4 d, and analyzed by toluidine blue staining after 7 d. The apoptotic osteoclasts were analyzed by Annexin V-FITC staining after 2, 4, 8, 12, 24, 36, and 48 hours, to observe their apoptosis. Their total RNAs were extracted, and analyzed for TRAP and Cathepsin K expressions by Real-time RT-PCR.. Compared with the control group, both of the PNG group and the NG group showed much less osteoclasts (TRAP positive cells), lower TRAP activity and TRAP and Cathepin K (CTSK) expression, and smaller number of bone resorption pits and areas. The PNG group show lower indexes than the NG group. Additionally, the PNG group reached the apoptotic peak of osteoclasts at 12 h after drug administration, whereas the NG group reached after 24 h. And the former had more apoptotic cells than the latter.. 8-PNG is much more active than NG in inhibiting the resorption of osteoclasts and inducing apoptosis of osteoclasts. Their only difference lies in 8-prenyl perssad, which is proved to be able to enhance the anti-bone resorption activity of 8-prenylnarigenin.

Topics: Acid Phosphatase; Animals; Bone Resorption; Cathepsin K; Cells, Cultured; Flavanones; Osteoclasts; Rabbits