Research of the effect in intermedin on cell proliferation repair of renal tubular cell hypoxia-reoxygenation injury / 中国药理学通报

ABSTRACT

Aim To evaluate the effect of intermedin (IMD)on cell proliferation and regeneration in rat tu-bular epithelial cell line (NRK-52E)that was subjec-ted to hypoxia-reoxygenation (H/R)injury.Methods The NRK-52E cells were divided into control group and three model groups (H/R,H/R +primitive vec-tor,H/R +IMD vector).The content of LDH was de-tected to observe the influence of IMD on H/R injury. The cell proliferation was detected by MTT.The cell cycle was detected by flow cytometry.Real-time PCR and western blotting were used to determine mRNA and protein levels.Results ① In comparison to the con-trol,H/R treatment decreased the cell viability and in-creased LDH activity (P <0.01 );in contrast,com-pared to H/R,IMD treatment ameliorated cell viability (79.1 5 ±1 .421 % vs 61 .22 ±1 .63%,P <0.05)and decreased LDH activities by 33.85% (P <0.01 ).②The proliferation of NRK-52E cells was significantly in-hibited by H/R treatment.In comparison to the con-trol,H/R treatment of NRK-52E cells increased the proportion of cells in the G0 /G1 phase but decreased the proportion of cells in the S and G2 /M phases. Moreover,the over-expression of IMD resulted in S and G2 /Mphase redistribution and the accumulation of G2 /M-phase cells.The real-time PCR and western blotting results indicated that the mRNA and protein expression levels of cyclin D1 ,CDK4 and p57 were increased in H/R-treated cells.IMD further stimulated this up-reg-ulated expression of cyclin D1 ,CDK4 and decreased the expression of p57 in NRK-52E cells.④Cyclin D1 had a predominantly nuclear localization in NRK-52Ecells,although cytoplasmic localization was also ob-served.Conclusion The study shows that the over-expression of IMD may promote renal cell proliferation and regeneration after renal tubular cell H/R injury via the up-regulation of cyclin D1 ,CDK and the down-reg-ulation of p57.