Figure 1
From: Methylene blue inhibits NLRP3, NLRC4, AIM2, and non-canonical inflammasome activation
Effect of methylene blue on NLRP3 inflammasome activation. (A) Chemical structure of methylene blue (MB). (B) Lipopolysaccharide (LPS)-primed bone marrow-derived macrophages (LPS-primed BMDMs) were treated with the indicated concentration of MB or ATP (2 mM) as a positive control. Secretion of active form of IL-1β was analyzed by immunoblotting using cell culture supernatants (Sup) and cell lysates (Lys). (C–E) LPS-primed BMDMs were treated with the indicated dosage of MB with/without nigericin (NG, 40 μM). (C) Secretion of IL-1β and caspase-1 (Casp1) and formation of Asc pyroptosome were analyzed by immunoblotting using Sup, Lys, and cross-linked pellets (Pellet) from whole cell lysates. The below schematic graph displays the chemical treatment process for inflammasome activation. IL-1β (D) and IL-18 (E) secretions were measured by ELISA. (F) LPS-primed BMDMs were treated with monosodium urate crystals (MSU, 800 μg/mL). Secretion of caspase-1 was analyzed by immunoblotting, and IL-1β secretion was measured by ELISA. (G) For cytotoxicity, BMDMs were treated the indicated dosages of MB, and cell number was measured by an automated cell counter. Triton x-100 (1%, Triton) treatment led to cell death. All immunoblot data shown are representative of at least three independent experiments. Bar graph presents the mean ± SD.
