The effects of Boehmeria nivea (L.) Gaud. on embryonic development: In vivo and in vitro studies

Aim of the study: Boehmeria nivea (L.) Gaud. was commonly used to treat miscarriages clinically. The aim of this study was to examine its safety for embryonic development. Materials and methods: Pregnant mice were randomly assigned into 5 groups, i.e. mice were oral-treated with distilled water (G1), with Boehmeria nivea extract of 2, 8 or 32 g/kg/day (G2, G3 or G4), and with 3 doses of vitamin A of 200,000 IU/kg as positive controls (G5). Meanwhile, IC₅₀ values for both embryonic stem cells (ESCs) and 3T3 cells were detected by cytotoxicity assays. Results: (1) The resorptions and malformed fetuses in G5 were significantly higher than G1 (P < 0.001), whereas the maternal body-weight and uterus-weight were lower than G1 (P < 0.05); (2) there was no difference in the fetal body-weight, maternal relative body-weight gain, liver-, kidney- or heart-weight, relative organ-weight, and histological examination among five groups; (3) there was no difference in IC₅₀ values between ESCs and 3T3 cells, but high concentration of Boehmeria nivea extract might significantly lower ESCs' viability (P < 0.05). Conclusion: Boehmeria nivea extract at 32 g/kg/day did not cause significant embryotoxicity or maternal toxicity in mice, although it might cause cytotoxicity in cultured ESCs at a high dose.