Fig. 6. Effect of RA on SLPI and thymosin β4 protein expression in MC3T3-E1 preosteoblasts on Ti surface. Total protein was extracted from MC3T3-E1 cells on Ti discs treated with or without 14 µg/ml RA and western blot was performed. (A) Secreted SLPI (Sup), Cytoplasmic SLPI (Lys) and Tβ4 protein expression. β-actin was used as an internal control. Quantitative analysis of SLPI (B, C) and Tβ4 (D) protein. RA: rosmarinic acid, Ti: titanium. *p<0.05, compared to control.