AQP-facilitated water transport induces NLRP3 inflammasome-related caspase-1 activation and mature IL-1β release.
a, IL-1β release by lung macrophages (LM) primed with LPS (0.1 μg/ml) exposed to isotonic (320 mosmol/kg H2O) or hypotonic medium (100 mosmol/kg H2O to 47 mosmol/kg H2O). n = 3 replicates/condition. b, flow cytometry forward scatter plots of lung macrophages subjected or not subjected to hypotonic shock (60 mosmol/kg H2O) in the absence or presence of HgCl2 (10 μm). Values indicated in the plots are differences between median forward scatter of cells exposed or not exposed to hypotonic shock. Levels of released IL-1β by lung (c) or peritoneal macrophages (PM) (d) exposed or not exposed to hypotonic shock (in the absence or presence of HgCl2 (10 μm). n = 3. e, Western blot analysis of mature IL-1β (IL-1β p17) in the supernatant (SN) and pro-IL-1β (IL-1β p37) in cell lysate of peritoneal macrophages exposed or not exposed to hypotonic shock in the absence or presence of HgCl2. f, fluorimetric measurement of cellular active caspase 1 in lung macrophages exposed or not exposed to hypotonic shock in the absence or presence of HgCl2 (10 μm). n = 3 or 4. Release of IL-1β by lung (g) or peritoneal macrophages (h) exposed or not exposed to silica (400 μg/ml) in the absence or presence of HgCl2 (10 μm)). n = 3 or 4. IL-1β release by lung (i) or peritoneal macrophages (j) exposed or not exposed to ATP (5 mm) in the absence or presence of HgCl2. n = 3 or 4. k, Western blot analysis of mature IL-1β and active caspase 1 (Casp1 p10) in the supernatant and pro-IL-1β in cell lysate of peritoneal macrophages exposed or not exposed to ATP in the absence or presence of HgCl2. l, mitochondrial activity assessed by optical density (OD) of reduced WST-1 and release of IL-6 by lung macrophages exposed or not exposed to ATP (5 mm) in the absence or presence of HgCl2 (10 μm) (m). n = 3 or 4. Data are means ± S.E. **, p < 0.01; ***, p < 0.001 upon exposure to hypotonic medium or ATP or no exposure, with HgCl2 or no exposure; ns, no significant difference. p values were calculated by Student Newman-Keuls test.