OBJECTIVETo study the effect of folic acid cooperating with soybean isoflavone on the oxidative status of neural tube defects (NTDs) pregnant rats induced by cyclophosphamide, to observe the relationship of the two factors, folic acid and the isoflavone and to look for the best co-intervention group.

METHODSThe 100 pregnant rats of 2.5-3 months old were randomly divided into the control group, model group, co-intervention groups and solo-intervention groups. The animals were executed on the 20th day of gestation as to examining the levels of antioxidative indices (GSH, GSH-Px, Se, Mn, Fe) in blood. The incidence rates of NTDs were calculated.

RESULTSThe interaction of folic acid and isoflavone had significant effect on the indices related with antioxidation (P < 0.05). Folic acid 0.7 mg/kg cooperated with isoflavone 160 mg/kg had the best intervention effects in our study. Compared with the solo-intervention by folic acid 1.4 mg/kg and isoflavone 320 mg/kg, the effect of co-intervention (folic acid 0.7 mg/kg cooperated with isoflavone 160 mg/kg) was significantly better (P < 0.05).

CONCLUSIONFolic acid should be the main protective factor of NTDs, and isoflavone might reinforce the protective effects of folic the acid on NTDs by increasing the antioxidative ability, however, the effect is related with the ratio of the two factors.