Fig. 1
S100A9 is a leptin-induced cue. Intracerebroventricular (icv) delivery of leptin was performed in two groups of STZ-treated, insulin-deficient mice: STZ–Leptin mice received leptin for 12 days; STZ–Leptin–STOP mice received the hormone for 10 days and were followed up to day 12. icv surgery was performed at day 0 and STZ injections were performed 14 and 7 days before surgery. a Blood glucose level in STZ–Leptin and STZ–Leptin–STOP mice. The gray line represents average values measured in age-matched non-diabetic healthy control mice. Twelve days after icv surgery, blood samples from STZ–Leptin and STZ–Leptin–STOP were collected and assessed for quantitative proteomic analysis. b Volcano plot representing the quantity of each circulating protein detected in STZ–Leptin–STOP divided by the quantity of each respective protein in STZ–Leptin mice. c S100A9 content in plasma. d S100a9 mRNA levels. e Western blot showing protein content in liver from a cohort of STZ-treated, insulin-deficient mice that underwent either icv leptin or icv saline treatment for 12 days. f Calprotectin content in plasma of STZ–Saline, STZ–Leptin, and their healthy controls and in STZ–Leptin and STZ–Leptin–STOP mice. Error bars represent SEM. For all panels n = 4/ group, except quantification in e that is from four STZ–Saline and eight STZ–Leptin mice. Statistical analyses were done using a two-tailed unpaired Student’s t-test when two groups were compared, and one-way ANOVA or two-way ANOVA (Tukey’s post hoc test) when more than two groups and more than one experimental condition/time point were compared, except in e where Welch’s t-test was used. In a ****P < 0.0001, ***P < 0.001, and **P < 0.01 STZ–Leptin–STOP vs Healthy; ####P < 0.0001 and ##P < 0.01 STZ–Leptin vs. Healthy; $$$P < 0.001 STZ–Leptin–STOP vs Leptin. In c–f *P < 0.05. Western blot results shown in c, e are cropped images of the whole gel. Source data are provided as a Source Data file
