FIGURE 1.

Neutrophilic SIRT1 levels are deceased in aged mice and deletion of Sirt1 in myeloid cells exacerbates chronic-plus-binge ethanol-induced liver injury. (A,B) Neutrophils were isolated from BM and blood of young (n = 6) and aged (n = 6) mice. Expressions of Sirt1 mRNA and protein were measured by RT-qPCR (A) and Western blotting (B), respectively. Quantification of proteins is shown in the right panel B. (C) Young (6–8 weeks) and aged C57BL/6J mice (24 months) were subjected to pair-fed or 10 day-plus-one binge (E10d+1B) ethanol feeding (n = 5 to 6 in each group). Mice were euthanized 9 h after gavage. BM and liver neutrophils were collected from pair-fed and EtOH-fed young or aged mice. Sirt1 mRNA levels were measured by RT-qPCR. (D) Western blot analysis of SIRT1 protein levels from BM neutrophils and peritoneal macrophages in Sirt1^Mye−/− and littermate control (Sirt1^f/f) mice. (E–G) Sirt1^Mye−/− (n = 7) and Sirt1^f/f (n = 9) were subjected to pair-fed or E10d+1B ethanol feeding. Mice were euthanized 9 h after gavage. Serum ALT levels were measured (E). Liver tissues were subjected to immunostaining with anti-MPO and anti-F4/80 staining, and the number of MPO⁺ neutrophils and F4/80⁺ macrophages were quantified (F). RT-qPCR analyses of liver Ly6g and F4/80 mRNA (G, left). RT-qPCR analyses of liver inflammatory cytokines and chemokines mRNA (G, right). Values represent means ± SEM. *p < 0.05; **p < 0.01; ***p < 0.001