%0 Journal Article %T Biphasic Response to Luteolin in MG-63 Osteoblast-Like Cells under High Glucose‑Induced Oxidative Stress %J Iranian Journal of Medical Sciences %I Shiraz University of Medical Sciences %Z 0253-0716 %A Abbasi, Naser %A Khosravi, Afra %A Aidy, Ali %A Shafiei, Massoumeh %D 2016 %\ 03/01/2016 %V 41 %N 2 %P 118-125 %! Biphasic Response to Luteolin in MG-63 Osteoblast-Like Cells under High Glucose‑Induced Oxidative Stress %K Luteolin %K Human osteoblast-like MG-63 cells %K High glucose %K Oxidative stress %K Alkaline phosphatase %R %X Background: Clinical evidence indicates the diabetes-induced impairment of osteogenesis caused by a decrease in osteoblast activity. Flavonoids can increase the differentiation and mineralization of osteoblasts in a high-glucose state. However, some flavonoids such as luteolin may have the potential to induce cytotoxicity in osteoblast-like cells. This study was performed to investigate whether a cytoprotective concentration range of luteolin could be separated from a cytotoxic concentration range in human MG-63 osteoblast-like cells in high-glucose condition.Methods: Cells were cultured in a normal- or high-glucose medium. Cell viability was determined with the MTT assay. The formation of intracellular reactive oxygen species (ROS) was measured using probe 2’,7’ -dichlorofluorescein diacetate, and osteogenic differentiation was evaluated with an alkaline phosphatase bioassay.Results: ROS generation, reduction in alkaline phosphatase activity, and cell death induced by high glucose were inhibited by lower concentrations of luteolin (EC50, 1.29±0.23 µM). Oxidative stress mediated by high glucose was also overcome by N-acetyl-L-cysteine. At high concentrations, luteolin caused osteoblast cell death in normal- and high-glucose states (IC50, 34±2.33 and 27±2.42 µM, respectively), as represented by increased ROS and decreased alkaline phosphatase activity.Conclusion: Our results indicated that the cytoprotective action of luteolin in glucotoxic condition was manifested in much lower concentrations, by a factor of approximately 26 and 20, than was its cytotoxic activity, which occurred under normal or glucotoxic condition, respectively. %U https://ijms.sums.ac.ir/article_40349_f192ea5912dc90795c7f415fa3390532.pdf