Objective: To observe the effects of seven kinds of flavonoids on recombinant human phosphatase of regenerating liver-3 activity.
Methods: The inhibitory effect of flavonoids was tested by DiFMUP assay. Calculation of IC50 values was performed according to the law of semi-effect-probit.
Results: Myricetin and gossypin could significantly inhibit recombinant PRL-3 activity in a concentration dependent manner with IC50 values of 55.54 and 68.86 micromol/L, respectively. Quercetin, luteolin and 7,8-Dihydroxyflavone had a weak inhibitory effect with IC50 values of 113.38, 151.56 and 249.49 micromol/L. respectively. While 3-hydroxyflavone and 6-hydroxyflavone had no significant effect on PRL-3 activity. Structure activity study indicated that C4 and C7 hydroxyls on the flavone skeleton were key functional groups to influencing PRL-3 inhibotory activity. The inhibitory effect of flavonoids on PRL-3 was increased with the number of hydroxyl group.
Conclusion: Myricetin and gossypin were two strong inhibitors on recombinant human protein tyrosine phosphatase PRL-3.