In vitro and in vivo effects of genistein on murine alveolar macrophage TNF alpha production

The present study was performed to determine whether genistein could inhibi t in vivo LPS-induced alveolar macrophage TNF alpha production and thus red uce the alveolar neutrophil. influx following LPS. In vitro incubation with genistein completely inhibited LPS-induced TNF alpha production by alveola r macrophages (AM) from BALB/c mice. Subsequently mice were pretreated with intraperitoneal genistein or vehicle, then received nasal LPS to induce an alveolitis. Genistein was then administered every eight hours for five day s following LPS. At 24 hours after LPS, the bronchoalveolar lavage (BAL) TN F alpha and ex vivo TNF alpha production from AM, were lower in the geniste in treated animals. As well, total BAL white blood cell (WBC) count was red uced in the genistein as compared to the vehicle-only group. The percent ne utrophils and the resolution of neutrophils were similar between genistein and vehicle groups. Therefore, genistein was able to decrease AM TNF alpha production, and was associated with a decrease in BAL WBC count post-LPS.