| Curcumin is component of turmeric,the yellow spice derived from the roots of the plant Curcuma longa.The current pharmacological study shows that it has anti-inflammatory,antioxidant,anti-tumor activities.Glioblastoma multiforme is a primary tumor of human brain.Cancer is characted by high mortality,hard to care recurrence after operation.The post-operation is based on radiotherapy.In this study,we investigated the inhibition of curcumin on hydroxyl radical,superoxide anion production and protein oxidative damage in biochemical system.The effects of curcumin on cell proliferation,cell morphology,reactive oxygen species change in NADPH oxidase activity and apoptosis,and to investigate whether the apoptosis of human glioma cells induced by curcumin is related to the anti-oxidation of curcumin and its potential oxidative activity.To provide a scientific basis for further understanding of the medicinal mechanism of curcumin and its further application.Following conclusions were demonstrated from this paper:1.Methyl violet method showed that 1-5 μmol/L curcumin on the hydroxyl free radical scavenging capacity gradually increased.7 μmol/L decreased significantly,indicating that the high concentration of curcumin scavenging ability decreased,may have the role of promoting oxidation;in the determination of protein oxidative damage,curcumin reduced free radical AAPH on bovine serum albumin(BSA)oxidative damage;the formation of superoxide anion has a certain inhibitory effect.However,in the presence of Cu2+,the antioxidant activity of curcumin decreased,and the protective effect of BSA on free radical damage was decreased.2.The results of MTT assay showed that curcumin or H2O2 could inhibit the proliferation of U87 cells.10 μmol/L and 20 μmol/L curcumin combined with H2O2 to enhance the inhibition of proliferation,indicating that curcumin may strengthen the role of H2O2-promote oxidation inhibition of cell growth.3.Morphological observation of inverted microscope,curcumin and H2O2 can cause changes in cell morphology,especially after the combination of curcumin and H2O2,cell shrinkage and other phenomena increased significantly.4.The results of Hoechst 33258 and AO/EB fluorescence staining and mitochondrial membrane potential showed that curcumin and H2O2 could decrease the chromatin condensation and nuclear margin of the nucleus or cytoplasm.And the apoptosis is obvious.The mitochondrial membrane potential of the cells decreased after 24 h of drug treatment,Indicating that the drug damaged the mitochondria.And the analysis of cell cycle shows that S-phase arrest by Curcumin or H2O2 in U87 cells.5.The results of DCFH-DA single staining and NADPH oxidase activity showed that intracellular reactive oxygen species(ROS)increased after 2 h of curcumin and H2O2,and the reactive oxygen species decreased after 6 hours.Curcumin alone or combined with H2O2 NADPH oxidase activity increased after 3 h,NADPH oxidase activity decreased after 6h,NADPH oxidase inhibitor APO could interfere with the activity of NADPH oxidase,and the activity of NADPH oxidase was decreased after 3 h and 6 h.DHE fluorescent probe to detect the changes of superoxide in U87 cells,indicating that 10 μmol/L,20 μmol/L curcumin alone or with 100 μmol/L H2O2 combined for 3 h and 6 h can cause the increase of intracellular superoxide content.The indicators of this study show that curcumin may exhibit a decrease in antioxidant activity in a certain biochemical system,a decrease in the protective effect of protein,and even a phenomenon of promoting oxidation.At the same time,curcumin alone or in combination with H2O2 The mitochondria of the cells were damaged,the levels of reactive oxygen species increased,the activity of NADPH oxidase increased,the content of intracellular superoxide increased,and the effect of S phase retardation and apoptosis occurred.In combination with the above,curcumin may induce apoptosis by inducing elevated levels of reactive oxygen,super oxidants,in human glioma cells. |
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