Effect of bone morphogenetic protein 4 on the infiltration of macrophages and the expression of nuclear factor-κB in mice model of unilateral ureteral obstruction

Abstract

Objective To observe the effect of bone morphogenetic protein 4(BMP4) on the infiltration of macrophages and the expression of nuclear factor-κB in mice model of unilateral ureteral obstruction(UUO). Methods C57BL/6 mice were randomly divided into four groups: injected intra-abdominally with saline-sham-operated group(saline-sham group, n=8), injection intra-abdominally with saline-UUO-operated group(saline-UUO group, n=8), injection intra-abdominally with anti-BMP4-sham-operated group(anti-BMP4-sham group, n=8), and injection intra-abdominally with anti-BMP4-UUO-operated group(anti-BMP4-UUO group, n=8). Either saline or anti-BMP4(group 200 μl/gram of body weight per day) were injected intra-abdominally for 7 days after surgery.Mice were sacrificed at 7th day to evaluate the expression of CD68 and p-P65 by immunohistochemical staining in each group.Besides, the p-P65 protein level was also analyzed by Western blotting in four groups. Results Immunohistochemical staining showed that the expressions of CD68 and p-P65 were significantly reduced in the kidney cortices in anti-BMP4-UUO group than in saline-UUO group(P<0.05, respectively). Similar to that, the p-P65 protein level was significantly reduced in the kidney cortices in anti-BMP4-UUO group than in saline-UUO group(P<0.05, respectively). Conclusion BMP4 participates in the process of renal interstitial inflammation in obstructive nephropathy, and may play a role through the activation of nuclear factor-κB signaling pathway. Key words: Bone morphogenetic protein 4; Ureteral obstruction, unilateral; Macrophage; Nuclear factor-κB