Induction of NLRP3 Inflammasome Activation by Heme in Human Endothelial Cells

Figure 5

Unfettered ROS production is critical in heme-mediated induction of IL-1β. (a) HUVECs were treated with LPS (0.01–10 μg/mL, 24 h). (b) HUVECs were primed with LPS (0.01–10 μg/mL, 24 h) then treated with heme (12.5 or 25 μmol/L, 4 h). (c–e) Naive or LPS-primed (10 μg/mL, 24 h) HUVECs were treated with heme (25 μmol/L) in the presence or absence of NAC (5 mmol/L). (a–c) Following the 4-hour heme treatment, ROS production was measured with DCFDA assay. (d) Following the 4-hour heme treatment, IL-1β mRNA level was determined by quantitative RT-PCR. (e) Active IL-1β levels in cellular supernatants (24 h) were determined by ELISA. Results are shown as mean ± SD () from one representative experiment of three. , , and .

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