Abstract: Abstract： Objective To study the effects of erythropoietin (rhEPO) in high glucose induced proliferation and apopto⁃ sis of human kidney proximal tubular epithelial (HK-2) cells, and the possible mechanism thereof. Methods HK-2 cells cultured in vitro were divided into several groups randomly: blank control group, high glucose group, mannitol group, rhEPO control group, different concentrations of rhEPO treatment groups (5, 10, 20 U/mL) and Rho kinase group. The reverse tran⁃ scription polymerase chain reaction (RT-PCR) was used to evaluate the mRNA levels of RhoA and ROCK after 24 hours. Tetrazolium salt method (MTT) was used to determine the cell proliferation. Cell apoptosis was detected by flow cytometry. Results Compared with blank control group the expression levels of RhoA and ROCK1 mRNA were significantly in⁃ creased in high glucose group (P < 0.05). RhoA, ROCK1 mRNA expressions significantly decreased in rhEPO group than those of high glucose group (P < 0.05). There was a positive correlation between the expression levels of RhoA mRNA and ROCK1 mRNA in high glucose group and rhEPO group. MTT method showed that rhEPO significantly promoted the prolifer⁃ ation of HK-2 cells (P < 0.05). Flow cytometry analysis showed that high glucose induced apoptosis in HK-2 cells, which was significantly inhibited in rhEPO group and Rho kinase group as compared to that of high glucose group in a concentra⁃ tion dependent manner (P < 0.05). Conclusion rhEPO can promote HK-2 cell proliferation and inhibit apoptosis, which may be related to RhoA/ROCK signaling pathway.

Key words: erythropoietin, recombinant, cell proliferation, apoptosis, rho-associated kinases, HK- 2 cells, high glu? cose;RhoA/ROCK signaling pathway