Effect of bone morphogenetic protein-7 transfected bone marrow mesenchymal stem cells on renal injury in rats with chronic renal failure / 中华肾脏病杂志

ABSTRACT

Objective To observe the bone marrow mesenchymal stem cells (BMSCs) modified by bone morphogenetic protein-7 (BMP-7) gene on the expression of renal BMP-7, transforming growth factor-β1 (TGF-β1) and vascular endothelial growth factor (VEGF), further to explore its protective mechanism on renal injury in rats with chronic renal failure (CRF). Methods BMSCs with high expression of BMP-7 gene (BMSCs-BMP-7) and empty vector-BMSCs (BMSCs-EV) were obtained by lentiviral-mediated gene transfection. Thirty male Sprague-Dawley (SD) rats were randomly divided into 5 groups, 6 in each group normal control (CON) group; PBS intervention (CRF with PBS infusion, CRF+PBS) group; BMSCs intervention (CRF with BMSCs infusion, CRF+BMSCs) group;BMSCs-EV intervention (CRF with BMSCs-empty vector infusion, CRF+BMSCs-EV) group and BMSCs-BMP-7 intervention (CRF with BMSCs-BMP-7 infusion, CRF+BMSCs-BMP-7) group. The CRF model was established by 5/6 nephrectomy. The CON group was a sham operation group. The corresponding 12-weeks interventions of each experimental group were performed after 2 weeks of modeling, the rats in the CON group and the CRF+PBS group were injected with 1 ml of PBS through the tail vein, and the other three groups were injected with 1 ml of the corresponding cell suspension once a week. At the time of sacrifice, blood and renal tissue samples were reserved. Serum creatinine (Scr) and blood urea nitrogen (BUN) were measured by routine biochemical methods, and the expression of BMP-7, VEGF, TGF-β1 in kidney was assayed by Western blotting. Results At the time of sacrifice, the levels of Scr and BUN in the CRF+PBS group were significantly higher than those in the CON group (all P<0.01); Compared with the CRF+PBS group, the Scr and BUN of the CRF+BMSCs group, CRF+BMSCs-EV group and CRF+BMSCs-BMP-7 group were decreased to different extents, the differences were statistically significant (all P<0.01);the Scr and BUN of the CRF+BMSCs-BMP-7 group were significantly lower than CRF+BMSCs group and CRF+BMSCs-EV group (all P<0.05). The expression of BMP-7 and VEGF were the lowest in the CRF+PBS group. Compared with the CRF+PBS group, the expression of BMP-7 and VEGF in the CRF+BMSCs group, CRF+BMSCs-EV group and CRF+BMSCs-BMP-7 group were significantly increased respectively (all P<0.05). The expression of the BMP-7 and VEGF in the CRF+BMSCs-BMP-7 group were higher than those in the CRF+BMSCs group and CRF+BMSCs-EV group (P<0.01). Compared with the CON group, the expression of TGF-β1 in the CRF+PBS group was significantly increased (P<0.01);compared with the CRF+PBS group, the expression of TGF-β1 in the CRF+BMSCs group, CRF+BMSCs-EV and CRF+BMSCs-BMP-7 group was significantly decreased (all P<0.01);the expression of TGF-β1 in the CRF+BMSCs-BMP-7 group was lower than the CRF+BMSCs and CRF+BMSCs-EV group (both P<0.01). Conclusions BMSCs modified by BMP - 7 has a protective effect on CRF rats; its protective mechanism may be related to antagonizing TGF-β1 and up-regulation of renal VEGF expression.