Oxidative damage theory is currently one of the predominant theories on the mechanisms of aging. Previous research has shown that antioxidants can extend the lifespan in the model organism by scavenging free radicals,inducing the expression of stress related genes and hormesis. However, recent studies have suggested that these pharmaceuticals may cause serious side effects,such as promoting oxidation,increasing the risk of cancer,and destroying the metabolic balance. The low absorption and targeting property also limit the efficiency of most antioxidants. As a result ,the correlation between antioxidants and lifespan extension remains to be demonstrated. We reviewed the research progress in the field of lifespan extension by antioxidants in recent years and provided references for future research in related areas.

Objective:To evaluate the effect of Oravive on remineralization and anti-demineralization ability with a laser fluorescence system.Methods:60 premolar specimens with artificial caries lesion were divided into three groups randomly.Samples were treated with Oravive,fluoride dentifrice and distilled water for 1 h,then etched for 24 h.A laser fluorescence system was used to make a quantitative record.Results:Oravive showed a statistically significant effect on remineralization and anti-demineralization ability.There was significant difference between Oravive and fluoride dentifrice on remineralization,but no difference on anti-demineralization.Conclusion:Oravive has good remineralization and anti-demineralization effects.Oravive is better than fluoride dentifrice on remineralization but equivalent to it on anti-demineralization.

AIM:To study the effect of centromere protein W ( CENP-W) down-regulation on human glioma U87 cells.METHODS:Small interfering RNA ( siRNA) was used to inhibit the expression of CENP-W in the U87 cells. The interference effect of siRNA was evaluated by RT-qPCR and Western blot .The proliferation of the cells was analyzed by MTT assay , BrdU staining and colony formation experiment .Transwell chamber assay was used to detect the invasion a-bility of the cells .The cell migration ability was measured by a scratch test .The changes of the cell cycle distribution and apoptosis were analyzed by flow cytometry .RESULTS:The results of MTT assay , colony formation experiment and BrdU staining showed that the cell proliferation and colony formation abilities in experimental group were significantly lower than those in control group and negative control group .The results of Transwell and scratch experiments showed that the migra-tion and invasion abilities in experimental group were weaker than those in blank control group and negative control group . The results of flow cytometry analysis showed that the cell cycle distribution in experimental group was arrested in G 0/G1 phase .The percentage of apoptotic cells in experimental group was higher than that in control group ( P<0.05 ) .CON-CLUSION:Down-regulation of CENP-W expression inhibits the proliferation , migration and invasion of human glioma cells and promotes the apoptosis of the cells , suggesting that CENP-W may be a potential target of gene therapy for human glioma.

Objective To study the effect of exsomes in SH-SY5Y cells after hypoxic ischemia/reperfusion injury.Methods Human umbilical vein endothelial cell hypoxic ischemia/reperfusion (HUVEC I/R) injury models were established,and the exosomes derived from HUVEC I/R were extracted and identified.SH-SY5Y cell hypoxic ischemia/reperfusion injury models (SH-SY5Y I/R) were established,and cells from SH-SY5Y I/R were divided into control group and exosomes-treatedgroup.The proliferation of SH-SY5Y cells was evaluated by CCK-8 assay 24,48and 72 h after cell inoculation.Transwell assay and wound-healing assay were used to examine the invasion and migration.Hochest33258 staining and Flow cytometry were used to monitor the changes of cell cycle and apoptosis.Expressions of Caspase-3,Bax and Bcl-2 were measured by real-time fluorescence quantificative-PCR and Western blotting.Results As compared with those in the control group,the proliferation abilities of SH-SY5Y cells in exosomes-treated group were significantly promoted (48 h:0.70±0.05 vs.0.94±0.08;72 h:0.83±0.05 vs.1.02±0.06),the cell cycle rate of S phase was significantly increased (14.39％±4.11％ vs.20.54％±3.46％),and G0/G1 phase was statistically decreased (71.26％± 5.24％ vs.66.87％±4.23％,P＜0.05).What's more,cell invasive was significantly promoted (44.00±6.56 vs.70.67±6.11),and relative wound injury area was significantly reduced in the exosomes treated group (0.61±0.07 vs.0.52±0.10);significant differences were noted between the two groups (P＜0.05).The mRNA expressions of Bax and Caspase-3 were significantly decreased and the mRNA expressions of Bcl-2 was significantly increased in the exosomes-treated group as compared with those in the control group (P＜0.05).Conclusion HUVEC I/R-derived exosomes play neuro-protective role in human SH-SY5Y cells after hypoxic I/R injury.