NCX1 represents an ionic Na+ sensing mechanism in macrophages
Fig 7
Pharmacological inhibition of NCX activity blocks HS-boosted MΦ activity.
(A) Immunoblotting and densitometry of NFAT5 6 h after LPS ± HS in RAW264.7 MΦs ± KB-R pretreatment (n = 3; paired t test; *p < 0.05). (B) Nos2 levels in RAW264.7 MΦs 4 h after LPS ± HS ± KB-R pretreatment (means ± SD; n = 10; Student t test; *p < 0.05). (C) Immunoblotting and densitometry of NFAT5 in RAW264.7 MΦs 4 h after LPS ± HS ± NiCl2 pretreatment (n = 4; paired t tests; *p < 0.05). (D) Nos2 levels in RAW264.7 MΦs 4 h after LPS ± HS ± NiCl2 pretreatment (means ± SD; n = 6; Student t test + Welch correction; *p < 0.05). (E) Immunoblotting and densitometry of NFAT5 in RAW264.7 MΦs 4 h after LPS ± HS ± SEA pretreatment (n = 5; paired t test; *p < 0.05). (F) Nos2 in RAW264.7 MΦs 4 h after LPS ± HS ± SEA pretreatment (means ± SD; n = 10–12; Mann–Whitney test; *p < 0.05). (G) RFP-GFP-mLC3 RAW264.7 MΦs were infected with Escherichia coli ± HS ± SEA pretreatment. Representative images 2 h after infection (RFP: red; GFP: green; scale bar: 10 μm). (H) Relative E. coli load at 2 h after infection of RAW264.7 MΦs ± HS ± SEA pretreatment (means ± SD; n = 12; Student t tests; *p < 0.05). For numerical raw data, please see S1 Data. For raw immunoblots, please see S1 Blots. CFU, colony forming unit; GFP, green fluorescent protein; HS, high salt; KB-R, KB-R7943 mesylate; LPS, lipopolysaccharide; mLC3, microtubule-associated protein 1 light chain 3; MΦ, monocyte/macrophage-like cell; NCX, Na+/Ca2+ exchanger; NFAT5, nuclear factor of activated T cells 5; Nos2, nitric oxide synthase 2; NS, normal salt; n.s., not significant; RFP, red fluorescent protein; SEA, SEA 0400.