Effect of chronic hypoxia on TGF-?1 expression and proliferation in MDCK Cells / 中华肾脏病杂志

ABSTRACT

Objective To investigate the effect of hypoxia on renal tubular cells and the mechanism of renal interstitial fibrosis. Methods Effect of chronic hypoxia on the proliferation, cell cycle and expression of TGF-?1 mRNA in cultured MDCK cells was examined. Quiescent cells were exposed to hypoxia (3%O2) or normoxia (18%O2) for 24, 48, 72 and 96 hours. At the end of each incubation, cellular proliferation and cell cycle were assessed by MTT method and flow cytometry, respectively. TGF-?1 mRNA level of cells were analyzed by semi-quantity RT-PCR. Results Exposure of MDCK cells to hypoxia induced a significant increase in proliferation and a significant decrease in the percentage of G0-G1 stage and a significant increase in the percentage of G2-M stage at 24, 48 and 72 hours. Meanwhile, TGF-?1 mRNA expression increased in a time-dependent manner as compared with normoxia group when MDCK cells were stimulated with 24, 48, 72 and 96 hours in hypoxia condition. Conclusion Chronic hypoxia-induced proliferation of MDCK cells is associated with increased expression of TGF-?1. Chronic hypoxia of renal tubular cells may be one of the causes of renal interstitial fibrosis.