Licoisoflavone A

Biol Trace Elem Res. 2001 Aug;81(2):169-75.

Inhibitory effects of licoisoflavones A and B and sophoraisoflavone A of Sophra mooracroftiana Beth ex Baker on copper-ion-induced protein oxidative modification of mice brain homogenate, in vitro.[Pubmed: 11554397]

METHODS AND RESULTS:
We present the results of an in vitro investigation of the inhibitory effects of licoisoflavones A and B and sophoraisoflavone A isolated from Sophra mooracroftiana BETH ex BAKER on copper-induced protein oxidative modification of mice brain homogenate in vitro. Although inhibitory effect of sophoraisoflavone A was stronger than those of licoisoflavones A and B, genistein as a related isoflavone, and mannitol as a hydroxy radical scavenger, inhibitory effects of licoisoflavones A and B were weaker than those of genistein and mannitol.
CONCLUSIONS:
These results demonstrated that the difference of inhibitory effects are dependent on the relation between chemical structures of these isoflavones, such as hydroxy group or benzopyran, and oxidative stress.

Blood Cells Mol Dis. 2001 Sep-Oct;27(5):894-900.

Monitoring of MRP-like activity in human erythrocytes: inhibitory effect of isoflavones.[Pubmed: 11783953]

A method to fluorometrically monitor efflux of 2',7'-bis-(carboxypropyl)-5(6)-carboxyfluorescein (BCPCF) from human erythrocytes was developed. Genistein, daidzein, sophoraisoflavone A, and Licoisoflavone A induced 50% inhibition (IC(50)) of BCPCF efflux at 15-70 microM. The IC(50) value of the most efficient isoflavone, Licoisoflavone A (15-25 microM), was comparable to that of indomethacin (approximately 10 microM) and markedly lower than for probenecid (100-200 microM), both known MRP1 inhibitors.
CONCLUSIONS:
Our results indicate that the human erythrocyte is a useful cell model in screening potential MRP inhibitors, that BCPCF is a good substrate for MRP, and that some isoflavones at low concentrations inhibit MRP-mediated efflux.