The effect of biochanin A on immune function in rats and tumor cell growth and viability

Abstract

Animals exposed to a single dose of biochanin A (BA) in vivo (8 mg kg‐1 by gavage or 4 mg kg‐1 intraperitoneal) had natural killer cell (NKC) activity similar to the control when observed 20 h after treatment. No effect on NKC response, antibody production or delayed‐type hypersensitivity reactions was seen in rats treated with the same BA doses administered three times a week for 3 weeks. Therefore, in vivo treatment of rats with BA in this study had little or no effect on the immune responses tested. NKC cytotoxicity was significantly enhanced in rat splenocytes exposed in vitro to 1 X 10‐5‐1 X 10‐12 M‐BA or genistein (GEN) in 2.5% dimethylsulfoxide (DMSO). However, the NKC response in the 2.5% DMSO vehicle‐treated controls was significantly suppressed. When the DMSO concentration was reduced to 0.5%, no effects were seen in BA, GEN or vehicle cultures. This suggests that BA and GEN treatment protected against suppression of NKC cytotoxicity by DMSO. Biochanin A treatment of tumor cells, YAC‐1 or EL4, in vitro did not affect viability, however, cell growth was significantly inhibited in both cell lines.