Production of hydrogen peroxide by serum and its involvement in cell proliferation in ROS 17/2.8 osteoblasts

The effects of hydrogen peroxide, which fetal bovine serum (FBS) releases, on proliferation have been studied in ROS 17/2.8 osteoblasts. Cell prolifer ation, when activated by FBS, was inhibited by catalase in ROS 17/2.8 osteo blasts, but did not in primary osteoblast-like cells. Serum-induced extrace llular signal-regulated kinase (ERK) activity was reduced by the pretreated catalase in ROS 17/2.8 osteoblasts. In addition, the present studies demon strate that addition of FBS led to an increase of fluorescene of dihydrorho damine 123, indicating formation of free radicals including hydrogen peroxi de in ROS 17/2.8 osteoblasts, but not in primary osteoblast-like cells. The se phenomena may account for the generation of reactive oxygen species duri ng cellular proliferation in ROS 17/2.8 osteoblasts.