Fig. 2: Nitroxoline inhibits inflammasome assembly.
From: Nitroxoline is a novel inhibitor of NLRP3-dependent pyroptosis
LPS-primed THP-1 ASC-GFP cells were treated with the indicated compound for 3 h before the addition of nigericin (Nig) for 1 h to examine ASC-speck formation. Next, 80 µM nitroxoline or an equivalent volume of DMSO was added. A Representative images of unfixed THP-1 ASC-GFP cells treated as indicated. ASC-GFP is depicted in green, and propidium iodide-positive cells are shown in red. Arrowheads indicate primed, non-pyroptotic cells. Cells were imaged at 32 × magnification, scale bar: 100 µm (top row). Unprocessed (central row) and SR-SIM-processed (bottom row) images of THP-1 ASC-GFP cells treated as indicated at 100 × magnification, scale bar 20 µm. Bar plots depicting the percentage of propidium iodide-positive (PI + ) (B) and ASC speck-positive (ASC speck + ) cells (C) assessed by flow cytometry (n = 4). D, E Representative Immunoblot of THP-1 WT cells treated as indicated. Full-length (GSDM-FL) and cleaved (GSDMD-NT) gasdermin D are presented with β-actin as a loading control (D). Bar plots presenting the ratio of GSDMD-NT to GSDM-FL (n = 4) (E). F, G Representative flow cytometry scatter plots of THP-1 cells treated as indicated. Quarter 2 (Q2) represents the FAM-FLICA, 7AAD-double positive pyroptotic cell population (F). Corresponding bar plot depicting the percentage of pyroptotic cells measured in Q2 (n = 4) (G). Data are presented as mean + SD. Data were analyzed using Student’s t-test. *p < 0.05.
