Effects of erythropoietin on renal tubular cells apoptosis induced by high glucose / 中华肾脏病杂志

ABSTRACT

Objective To investigate whether erythropoietin (EPO) can inhibit the proapoptotic effect of high glucose on rat proximal tubular epithelial cells, and the possible mechanisms in which EPO exerts its anti-apoptotic role. Methods Rat proximal tubular epithelial cells (NRK-52E) were divided into 5 groups normal control group, osmolarity control group, high glucose group, high glucose with EPO (50 U/ml) group and high glucose with EPO (100 U/ml) group. The expression of EPO receptor (EPOR) in NRK-52E cells was examined by immunocytochemistry. The effect of high glucose on the expression of EPOR was detected by Western blotting. The rate of apoptosis was evaluated by flow cytometry Annexin V-FITC/PI double stains. The intracellular ROS was detected using fluorescent probe CM-H2DCFDA. The expression of bcl-2, bax and caspase-3 mRNA were examined by RT-PCR. Results The expression of EPOR was demonstrated in NRK-52E cells, and high glucose could up-regulate the expression of EPOR. High glucose could induce oxidative stress in NRK-52E cells, and up-regulate the mRNA expression of bax and caspase-3, down-regulate the mRNA expression of bcl-2. These effects of high glucose on NRK-52E cells could be reversed by EPO. Conclusion EPO inhibits NRK-52E cells apoptosis induced by high glucose through attenuating oxidative stress,up-regulating theexpression of bcl-2 mRNA and down-regulating the expression of bax and caspase-3 mRNA, which may be mediated by EPOR.