Doxy induction of MnSOD biochemical activity in MnSODtet/tet bone marrow stromal cells. Units of biochemical activity are shown. In no doxy, both MnSODtet/+ and MnSODtet/tet cells had lower MnSOD levels than MnSOD+/+ cells (*P = 0.0297 and ◆ = 0.0108, respectfully). When grown in doxy, MnSODtet/+ and MnSODtet/tet cells showed elevated MnSOD levels compared to the same cells in no doxy (#P =0.0405 and ■P = 0.0135, respectively). Furthermore, in doxy both MnSODtet/+ and MnSODtet/tet cells achieved levels of biochemically active MnSOD comparable to the levels in MnSOD+/+ control cells (▲P = 0.3180 and ▼P = 0.1602, respectively).