Dang-Gui-Bu-Xue-Tang (DBT), a combination of Angelicae Sinensis Radix and Astragali Radix, is a widely used herbal decoction in traditional Chinese medicine primarily to promote or invigorate the "blood". In this study, we explored this ancient formulation and provide evidence of its blood-toning properties. We used the improvement iron uptake as promote or invigorate the "blood" indicator. Ferritin formation of Caco-2 cells in vitro assay and diet-induced anemia (DIA) in rat model were used to prove its improvement iron uptake and ameliorating effects. Finally, the iron-DBT interactions were measured by iron-binding assay. We first demonstrated DBT increased uptake of ferrous iron through the biosynthesis of ferritin by Caco-2 cells and determined which complementary treatment would provide optimum results. Thereafter, effects of the treatment on improving the bioavailability of absorbed iron in the form of hemoglobin (Hb) were established using a DIA-animal model. The results showed that DBT slightly improved Hb levels compared with the baseline Hb and pretreatment with DBT for 2 hours prior to supplementation with ferrous sulfate provided the greatest gain in Hb levels in DIA rats. However, DBT and ferrous sulfate were co-treated with Caco-2 cell or DIA rats, the ferritin formation and Hb levels both were decreased. In iron-binding assay, the DBT extract influenced the free Fe(II) type in the FeSO4 solution. Therefore, we suggest that complementary treatment with DBT and iron supplementation can have a strong ameliorating effect on iron-deficiency anemia in clinical settings, but needs a 2-hour interval of DBT administration prior to ferrous sulfate treatment.
Keywords: Dang-Gui-Bu-Xue-Tang; ferritin; ferulic acid; herb–drug interaction; iron uptake; iron-deficiency anemia.