Baicalein induces human osteosarcoma cell line MG-63 apoptosis via ROS-induced BNIP3 expression

Baicalein, a flavonoid compound, is one of the active constituents of the root of Scutellariae Radix. Its antitumor effects have attracted widespread attention worldwide. One of its major functions is to induce the apoptosis of tumor cells, but the antitumor mechanism is currently unclear. In the present study, we found that baicalein increased MG-63 cell mortality in a dose-dependent manner. Meanwhile, baicalein activated apoptosis through induced intracellular reactive oxygen species (ROS) generation, and that ROS scavenger N-acetyl-cysteine (NAC), glutathione (GSH), and superoxide dismutase (SOD) apparently inhibited intracellular ROS production, consequently attenuating the baicalein-induced apoptosis. Baicalein also induce the mitochondrial fragmentation which precedes the cell apoptosis. This morphological alteration is accompanied by an increase in the expression of the protein BNIP3 as well as Mul1 and Drp1. Furthermore, we show that the inhibition of BNIP3 expression can inhibit cell apoptosis by baicalein treatment. Taken together, our results bring the evidence of a mechanism that links apoptosis and ROS-induced BNIP3 expression in MG-63 cells with bacalein treatment and suggest that baicalein has a good potential as an anti-osteosarcoma drug.