Macrophages undergo metabolic adaptation in an in vivo model of hemolytic SCD. (A) Blood was collected from transgenic B6/129 knockin mice (Townes SCD model) that expressed human hemoglobin α homozygous for either the β^A or β^S sickle hemoglobin, and serum heme concentrations were measured (n = 5 per group). (B) mRNA expression of Hmox1, G6pd, and Pgd in spleens of β^A or β^S mice (n = 5 per group). (C) mRNA expression of Hmox1, G6pd, and Pgd in livers of β^A or β^S mice (n = 5). (D) G6PD activity measured as the rate of NADPH synthesis in supernatants of whole liver lysates of β^A or β^S mice (n = 5 per group). (E) Correlation of serum heme concentration with liver G6PD activity in β^A or β^S mice (n = 5 per group). (F) Representative gating strategy for FACS of macrophage-like cells from spleens of β^A or β^S mice. (G) Abundance of macrophages as percentage of live CD45⁺ cells from β^A or β^S mice (n = 4). (H) mRNA expression of G6pd and Pgd in FACS-sorted splenic macrophages from β^A or β^S mice. (I) Schematic describing CORM3 treatment regimen and peritoneal cell isolation. (J) mRNA expression of G6pd and Pgd in isolated peritoneal cells from mice treated with saline or CORM3 for 7 days (n = 5). Data are represented as mean ± SEM. Statistical significance between 2 groups was determined by Welch’s unpaired t test. Significance between more than 2 groups was determined by one-way ANOVA with post hoc Tukey’s or Dunnett’s multiple comparisons tests, as appropriate, to determine differences between specific groups. Correlation analysis is based on determination of Pearson coefficient, and significant correlations are presented as R² values. FITC, fluorescein isothiocyanate; SSC-A, side scatter area.*P < .05; **P < .01; ***P < .005.