The injurious effects of reactive oxygen species on osteoblasts and the potential protective role played by green tea polyphenols (GtPP) were investigated using primarily cultured rat calvarial osteoblasts. Oxidative stress was induced in cultured osteoblasts, either by adding 100 mmol/L H 202 or by the action of 40 U/L xanthine oxidase (XO) in the presence of xanthine (250 μmol/L). After incubation, the cellular viability, function and morphology were evaluated. Both treatments produced a significant reduction in osteoblast viability, as assessed by a two-colored fluorescence staining method combined with flow cytometric analysis and MTT assay. A significant reduction in the alkaline phosphatase activity was observed after H202 addition, whereas XO did not have the same effect. On the microscopic observations, the morphological changes and intracellular ultrastructural damages were remarkably induced by both treatments. The H202-induced alterations were prevented by pre-incubating the osteoblasts with 200 μ/ml GtPP for 1 h. When the oxidative stress was induced by XO, the cellular viability and morphology was also maintained at the same polyphenol concentration. These results demonstrate that GtPP can act as a biological antioxidant in a cell culture experimental model and protect cells from oxidative stress-induced toxicity.
|Number of pages||13|
|Journal||Cell Biology and Toxicology|
|Publication status||Published - 2003 Oct 1|
All Science Journal Classification (ASJC) codes
- Cell Biology
- Health, Toxicology and Mutagenesis