Effects of (+)-vitisin A (Vt-A) on RANKL-induced tartrate-resistance acid phosphatase (TRAP) activity and cell viability in RAW264.7 cells.

(A) For osteoclast differentiation, RAW264.7 cells were stimulated with RANKL (100 ng/ml) and TRAP activity was assayed in cell lysates as described in methods. (B) The effect of Vt-A on cell viability was evaluated by MTT assay. Each value is the mean ±SEM of five independent experiments each performed in triplicate. *p<0.05 and **p<0.01, different from values after treatment with RANKL alone.