Induction of NLRP3 Inflammasome Activation by Heme in Human Endothelial Cells

Figure 6

Albumin inhibits heme-induced NLRP3 inflammasome activation in HUVECs in vitro and heme-induced peritoneal infiltration of leukocytes in vivo. (a–c) HUVECs primed with LPS (10 μg/mL, 24 h) were stimulated with heme or heme-albumin (H-A, 25 μmol/L). (a) IL-1β mRNA level (4 h) was determined by quantitative RT-PCR. (b) Active IL-1β levels in cellular supernatants (24 h) were determined by ELISA. (c) ROS production (4 h) was measured with DCFDA assay. Results are shown as mean ± SD () from one representative experiment of two. , , and . (d) C57BL/6 mice were injected (i.p.) with heme (300 nmol/mice), heme-albumin (h–a, 300 nmol/mice), or PBS ( in all groups). Peritoneal cavity was rinsed, and the total number of leukocytes was counted after 16 h of treatment. Results are shown as mean ± SD, .

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