Isosakuranetin stimulates melanin accumulation in a dose-dependent manner. In addition, Isosakuranetin at 30 μM gradually increases the expression of Tyr, TRP1, and TRP2 after 48 and 72 h. The MTT assay shows that Isosakuranetin decreases the number of cells at concentrations greater than 45 μM. Further analysis of trypan blue staining demonstrates that Isosakuranetin does not affect the viability of B16 melanocytes, but shows that Isosakuranetin decreases their proliferation rate. The tyrosinase activity of B16 melanocytes treated with 15 and 30 μM Isosakuranetin for 72 h is significantly increased by 2- and 3.2-fold, respectively, in comparison with that of the control cells.
Isosakuranetin dose-dependently increases the paw-withdrawal threshold within the dose range of 1.5 to 6 mg/kg. Post hoc analysis reveals that Isosakuranetin increases the paw-withdrawal threshold and statistical significance is seen at times 30 and 40 min for the dose of 3 mg/kg and 30 to 60 min for the dose of 6 mg/kg.