Effect of pioglitazone on the expression of PPARγ, NF-κB c-Rel and Bcl-xL in cultured rat cortical neurons after the oxygen-glucose/reoxygenation / 国际脑血管病杂志

ABSTRACT

Objective To investigate the effect of pioglitazone (PIO) on the expression of peroxisome proliferators-activated receptor γ (PPARγ),nuclear factor-κB (NF-κB) c-Rel and anti-apoptosis factor Bcl-xL in cultured Wistar rat cortical neurons after oxygen-glucose deprivation/reoxygenation (OGD/R).Methods The rat cerebral cortical neurons were primarily cultured in vitro and a model of OGD/R was induced.The rats were divided into 7 groupsnormal,OGD 4 h/R 6 h,OGD 4 h/R 12 h,OGD 4 h/R 6 h + PIO,OGD 4 h/R 6 h + PPARγ inhibitor T0070907 (TIO),OGD 4 h/R 12 h + PIO,and OGD 4 h/R 12 h + TIO groups.Western blot was used to detect the expression of PPARγ and NF-κB c-Rel protein in neurons.Reverse transcriptionpolymerase chain reaction assay was used to detect the expression of Bcl-xL mRNA in neurons.Results Western blot analysis showed that the expression levels of PPARγ and NF-κB c-Rel proteins after OGD/R were increased significantly compared to those of the normal group (P ＜0.01).After giving PIO,the expression levels of PPARγ and NF-κB c-Rel proteins were further increased,and they were significantly higher than those in the OGD 4 h/R 6 h and OGD 4 h/R 12 h groups (P ＜0.01),and after giving TIO,the expression levels of PPARγ and NF-κB c-Rel proteins were decreased,and they were significantly lower than those in the OGD/R group (P ＜0.05) and the corresponding PIO group (P ＜0.01).Reverse transcription-polymerase chain reaction analysis showed that the expression level of Bcl-xL mRNA in the OGD 4 h/R 6 h group was significantly higher than that in the normal group (P ＜0.01).The expression level of Bcl-xL mRNA in the PIO group was significantly higher than that in the OGD 4 h/R 6 h and OGD 4 h/R 12 h groups (P ＜0.01).After giving TIO,the expression of Bcl-xL mRNA was decreased.It was significantly lower than that in the OGD/R and corresponding PIO groups (P ＜ 0.05 and P ＜ 0.01).Conclusions PIO can upregulate the expression of PPARγ protein in cultured cortical neurons after OGD/R,and then increase the expression of anti-apoptotic factor Bcl-xL mRNA of NF-κB c-Rel regulation.This may be the part mechanism of PPARγ neuroprotective effect.