Figure 8. TR-independent pathways are involved in.

TH-enhanced NO production and iNos expression. RAW264.7 cells were treated with or without (Control) 100 nM T3 or 1 µM T4 for 24 h in the presence or absence of 2.5 µM LY294002 (LY, PI3K inhibitor), 10 µM PD98059 (PD, ERK1/2 inhibitor) or 10 µM tetraiodothyroacetic acid (Tetrac, T3/T4 analog to integrin αvβ3 receptor). Vehicle for THs (NaOH) or inhibitors (DMSO) was added to control or inhibitor-untreated cells. (A) Cells were infected with heat-killed FAM20 (MOI  = 200) for 24 h. Levels of nitrite in the supernatants were determined by a Griess assay. *, P<0.05 (Student’s t-test, compared to cells without inhibitor treatment). (B) Cells were infected with heat-killed FAM20 (MOI  = 200) for 24 h. Expression of iNos protein in cells was detected by Western blot using an anti-iNos Ab. Densitometry of Western blot bands was performed using Image J software and relative expression level of iNos protein is presented after normalization to GAPDH. Data is displayed as arbitrary units set to 100 for the control without TH treatment. (C) RAW264.7 cells were treated as indicated above and infected with live FAM20 (MOI  = 200) for 3 h. Intracellular survival of meningococci was determined using a gentamicin protection assay as described in Materials and Methods. Experiments were performed in triplicate and data are presented as means ±SD. *, P<0.05 (Student’s t-test, compared to cells without inhibitor treatment).