WT and Il1r1–/– mice were injected with either PBS or LCWE and allowed to recover for 5 weeks before receiving ISO or VEH daily for 10 consecutive days. Twenty-four hours after the last ISO or VEH injection, heart tissues were collected and examined. (A) Immunohistochemistry of CD31 expression in heart tissues of WT and Il1r1–/– mice injected either with PBS or LCWE and subsequently treated with VEH or ISO. (B) Quantification of CD31 staining in heart tissues from PBS- or LCWE-injected WT mice treated with ISO or VEH (left) and LCWE-injected Il1r1–/– mice treated with ISO or VEH (right). The graph represents the percentage of CD31-positive area of total area analyzed. (C and D) Western blot analysis (C) and quantification (D) of VEGF expression in heart tissue homogenates from PBS- and LCWE-injected WT mice. Data are presented as mean ± SEM. *P < 0.05, ***P < 0.001 by 2-way ANOVA or Student’s unpaired t test, 3–7 mice per group. LCWE, Lactobacillus
casei cell wall extract; ISO, isoproterenol; VEH, vehicle.