Relaxin Attenuates Contrast-Induced Human Proximal Tubular Epithelial Cell Apoptosis by Activation of the PI3K/Akt Signaling Pathway In Vitro

Figure 5

Effects of RLX on the expression of pAkt and apoptosis proteins. RLX (10 ng/mL) or LY294002 (50 μM) was added 1.5 hours before ioversol treatment. Cells were then exposed to ioversol (100 mg/mL) for 30 minutes and were further incubated for 24 hours in the absence of ioversol. The expression of pAkt was significantly lower in ioversol treated cells compared with the control, which could be reversed by treatment of RLX. Furthermore, this effect was attenuated by Akt inhibitor LY294002. Expression of cleaved caspase3 was markedly increased following the exposure to ioversol, whereas cleaved caspase-3 decreased when cotreated with RLX. This antiapoptotic effect was abrogated by the PI3K/Akt inhibitor LY294002. Bcl-2 expression was significantly reduced in the ioversol treated HK-2 cells; while coincubated with RLX, the expression of Bcl-2 was restored. The expression of Bax showed a reverse association with that of Bcl-2. The ratio of Bax/Bcl-2 decreased in RLX treated cells compared to control or ioversol groups. Experiments were repeated three times. ; .

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