Figure 5.

Activation of HIF protected HK-2 injury by mediating miR-21. (A–C) Hydrolysis of HIF was inhibited by 500 μM L-Mimosine or 150 μM CoCl₂. Elevated expression of HIF increased expression of miR-21. (D,E) Interfered expression of HIF1α and/or 2α by transfected with HIF1α and/or 2α siRNA to HK-2 cells under hypoxia/reoxygenation and normoxic conditions was confirmed by qRT-PCR and western blotting. (F) Interference expression of HIF1α and/or 2α modulated elevated expression of miR-21 induced by HR. (G) Apoptosis of the HK-2 cells was accessed by annexin-V-FITC/PI staining and determined by flow cytometry. Treatment of HK-2 cells with L-Mimosine or CoCl₂ attenuated HR induced apoptosis. (H) Group data from (E). (I) HR increased late apoptosis of HK-2 cells, after inhibiting HIF1α and/or 2α, the effect of HR on apoptosis was enhanced. (J) Group data from I. *P < 0.05, **P < 0.01, *** < 0.001, n = 3 for flow cytometry, n = 6 for others.