Activating PPARγ Increases NQO1 and γ-GCS Expression via Nrf2 in Thrombin-activated Microglia

The present study aimed to explore the molecular mechanisms underlying the increase of nicotinamide adenine dinucleotide phosphate:quinine oxidoreductase 1 (NQO1) and γ-glutamylcysteine synthetase (γ-GCS) in brain tissues after intracerebral hemorrhage (ICH). The microglial cells obtained from newborn rats were cultured and then randomly divided into the normal control group (NC group), model control group (MC group), rosiglitazone (RSG) intervention group (RSG group), retinoic-acid intervention group (RSG+RA group), and sulforaphane group (RSG+SF group). The expression levels of NQO1, γ-GCS, and nuclear factor E2-related factor 2 (Nrf2) were measured by real-time polymerase chain reaction (RT-PCR) and Western blotting, respectively. The results showed that the levels of NQO1, γ-GCS and Nrf2 were significantly increased in the MC group and the RSG group as compared with those in the NC group (P<0.01). They were found to be markedly decreased in the RSG+RA group and increased in the RSG+SF group when compared with those in the MC group or the RSG group (P<0.01). The RSG+SF group displayed the highest levels of NQO1, γ-GCS, and Nrf2 among the five groups. In conclusion, a medium dose of RSG increased the anti-oxidative ability of thrombin-activated microglia by increasing the expression of NQO1 and γ-GCS. The molecular mechanisms underlying the increase of NQO1 and γ-GCS in thrombin-activated microglia may be associated with the activation of Nrf2.