Figure 1.

Effect of soy isoflavones on intracellular arginase-1 (Arg-1) levels in CD11b⁺ leukocytes in the lungs at 1 week postradiation. (A–C) Single-cell suspensions obtained from the lungs were analyzed by flow cytometry. (A) Gating strategy for CD11b⁺ and CD11b⁺Arg1⁺ cells. CD11b⁺ myeloid cells were gated within the CD45⁺ lung leukocytes. Intracellular Arg-1 cells were gated within the CD11b⁺ myeloid cells. (B) Analysis of CD45⁺CD11b⁺ leukocytes in the lungs from control (Con) and mice treated with soy (Soy), radiation (Rad), or radiation + soy (R + S). Percentages of CD11b⁺ cells within CD45⁺ cells are presented as mean ± SEM (n = 3 mice/group). (C) Intracellular Arg-1 expression in CD11b⁺ lung myeloid cells. Percentages of CD11b⁺Arg-1⁺ cells within CD45⁺ leukocytes are presented as mean ± SEM (n = 3 mice/group). *p < 0.05 for radiation compared to control, and **p < 0.01 or R + S compared to Rad alone. (D,E) Western blot analysis of Arg-1 on lung lysates obtained at 1 week after radiation. Radiation caused a significant decrease in Arg-1, but Arg-1 levels in R + S-treated lungs were comparable to those of Con or Soy lungs as confirmed in (E) by quantification of band intensities using ImageJ (NIH) densitometry analysis. The data are presented as mean ± SEM (n = 2 mice/group). ***p < 0.001 for radiation compared to control, and **p < 0.01 for R + S compared to radiation alone.