Mechanism underlying docosahexaenoic acid-induced regulation of angiopoietin expression in human brain vascular pericytes subjected to oxygen-glucose deprivation and restoration: the relationship with SSeCKS / 中华麻醉学杂志

ABSTRACT

Objective To evaluate the relationship between the mechanism underlying docosahexaenoic acid (DHA)-induced regulation of angiopoietin expression and Src-suppressed C kinase substrate (SSeCKS) in human brain vascular pericytes (HBVPs) subjected to oxygen-glucose deprivation and restoration (OGD/R).Methods HBVPs were seeded in 96-well or in 6-well plates at a density of 2× 105 cells/ml and divided into 5 groups (n =18 each) using a random number tablecontrol group (group C),OGD/R group,DHA group (group D),SSeCKS gene silencing group (group S) and SSeCKS gene silencing plus DHA group (group SD).The model of OGD/R injury was established as followsthe cells were subjected to O2-glucose deprivation for 24 h in glucose-and serum-free culture medium aerated with 94％ N2-5％ CO2-1％ O2 followed by restoration of O2-glucose supply for 6 h in high-glucose DMEM culture medium in normal atmosphere.DHA was added at 1 h before hypoxia with the final concentration of 40 μmol/L in group D.Small interfering RNA induced SSeCKS gene silencing in S and SD groups.Subsequently,DHA with the final concentration of 40 μmol/L was added at 1 h before hypoxia in group SD.At 6 h of reoxygenation,the cell survival rate was determined by CCK-8 assay,the amount of LDH released was detected using ELISA,and the expression of SSeCKS,angiopoietin-1 (Ang-1) and Ang-2 was detected by Western blot.Results Compared with group C,the cell survival rate was significantly decreased,the amount of LDH released was increased,the expression of SSeCKS and Ang-1 was down-regulated,the expression of Ang-2 was up-regulated,and Ang-1/Ang-2 ratio was decreased in group OGD/R,and the expression of SSeCKS was down-regulated in group S (P＜0.05).Compared with group OGD/R,the cell survival rate was significantly increased,the amount of LDH released was decreased,the expression of SSeCKS and Ang-1 was up-regulated,the expression of Ang-2 was down-regulated,and Ang-1/Ang-2 ratio was increased in group D (P＜O.05),and no significant change was found in the parameters mentioned above in group SD (P＞0.05).Compared with group D,the cell survival rate was significantly decreased,the amount of LDH released was increased,the expression of SSeCKS and Ang-1 was down-regulated,the expression of Ang-2 was up-regulated,and Ang-1/Ang-2 ratio was decreased in group SD (P＜0.05).Conclusion The mechanism by which DHA increases the ratio of Ang-1/Ang-2 may be totally related to up-regulation of SSeCKS expression in HBVPs subjected to OGD/R.