Fig. 9.
Role of Ca2+ on ER stress-induced NLRP3 activation in THP-1 monocytes and susceptibility towards ER stress. By using an ELISA assay, IL-1β secretion was analyzed in supernatants obtained from THP-1 cells primed with 1 μg/mL LPS during 24 h and then treated with 10 μg/mL TM for 8 h in the presence or absence of 10 μM Ru360 (A), or 1 μM Xest C (B), or 5 mM NAC (C) which were pre-incubated during 1 h. Results were calculated relatively to LPS-treated cells and represent the mean ± SEM of at least three independent experiments. Statistical analysis: t-test was used for comparisons between Ctrl and LPS (###p < 0.001), LPS plus TM and LPS (**p < 0.01 or ***p < 0.001), LPS plus TM plus Xest C and LPS plus TM (tp < 0.05), and LPS plus TM plus Ru360 and LPS plus TM (tp < 0.05). Susceptibility of THP-1 cells to ER stress induced by TM (5 or 10 μg/mL) exposure during 4, 8 or 24 h was assessed by the resazurin assay (D). Results represent the mean ± SEM of at least three independent experiments and were calculated relatively to control values (untreated cells). Statistical significance between control and treated cells was determined using the one-way ANOVA test, followed by Dunnett’s post hoc test: **p < 0.01; ***p < 0.001