Figure 3From: Combustion-derived flame generated ultrafine soot generates reactive oxygen species and activates Nrf2 antioxidants differently in neonatal and adult rat lungs In vitro Nrf2 reporter assays. Human U937 macrophages were transiently transfected with the Nrf2 luciferase reporter construct and subsequently treated with PFP or t-BHQ (positive control). (A) A dose-dependent increase in Nrf2 activity was observed after PFP treatment. Treatment with 2 μg/cm2 PFP yielded a significant response compared to controls. At 10 μg/cm2, the Nrf2 reporter generated similar levels compared to t-BHQ. (B) PFP treatment increases binding activity of Nrf2 at a consensus ARE binding element using GMSA with ARE consensus oligonucleotide after treatment of U937 macrophages with PFP (2 μg/cm2) and t-BHQ (10 μM) for 90 minutes. (C) HMOX1 mRNA was upregulated approximately 6-fold after 2 μg/cm2 PFP treatment compared to controls. Data are presented as mean+SEM (n=3 separate experiments), * significantly different compared to control.Back to article page