Tanshinol Rescues the Impaired Bone Formation Elicited by Glucocorticoid Involved in KLF15 Pathway

Figure 6

Tanshinol counteracts inhibition of osteoblastic differentiation and bone formation elicited by Dex in connection with downregulation of KLF15. C2C12 cells and MC3T3-E1 cells were transfected with KLF15 siRNA for 18 h, followed by DMEM medium supplemented with Dex in the presence or absence of tanshinol for 7 days. (a) Capacity of osteoblastic differentiation in C2C12 cells was determined by using ALP staining. (b) Capacity of osteoblastic differentiation in MC3T3-E1 cells. Original magnification (×100) in representative microscopic images. (c) Effects of knockdown of KLF15 on activity of bone formation. MC3T3-E1 cells were treated with KLF15 siRNA for 18 h, followed by Dex treatment with or without tanshinol for 21 days. Mineralization activity with the indicated treatments was stained using Alizarin Red S at day 21. Original magnification (×100) in representative microscopic images (upper panel). Quantitative determination was carried out by CPC solution (pH 7.0) (lower panel). Vehicle: vehicle control (Veh). Values are means ± SD of at least three independent experiments. versus vehicle control; versus GC treatment; versus corresponding scrambled control.

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