Omi/HtrA2在窒息后血清诱导人近曲肾小管皮细胞凋亡中的作用

Objective To investigate the mechanism of inducing apoptosis of Omi/HtrA2 in renal tubular cells with postasphyxial serum of neonate. Methods Human renal proximal tubular cell line HK-2 cell was used as target cell. They were divided into three groups: control group, asphyxia group and Ucf-101 (Omi/HtrA2 special inhibitor) treated group. The challenge concentration of serum obtained from neonates 24 hours after asphyxia was 20%,and the treatment concentration of Ucf-101 was 10 μmol/L.The Omi/HtrA2 translocation in renal tubular cells was observed with confocal microscopy, and the rate of apoptosis was detected with flow cytometer. Results It was found that Omi/HtrA2 was translocated into cytoplasm in asphyxia group, and the rate of Omi/HtrA2 translocation in HK-2 cells of asphyxia group was significantly increased (28. 1 % vs. (9.4±2.1)%, P<0. 01]. Compared with the control group, after being treated with postasphyxial serum, the rate of apoptosis of HK-2 cells in asphyxia group wa ssignificantly increased (36. 3±4. 4)% vs. (12. 4±2. 9) %, P<0. 01]. Compared with asphyxia group, the rate of apoptosis in HK-2 cells in Ucf-101 treated group was significantly decreased (27. 0± 3. 9)% vs. (36.3±4.4) %, P<0. 01]. Conclusion These experimental data demonstrates that postasphyxial serum of neonate can induce apoptosis of HK-2 cells, and translocation of Omi/HtrA2 from mitochondria into cyto-plasm may play an important role in its intracellular signal transduetion mechanism in induction of apoptosis.

Role of Omi/HtrA2 in renal tubular cells apoptosis induced by postasphyxial serum of neonate