Aims: The potential of cell based therapies in diseases involving ischemia/reperfusion is greatly hampered by the excessive loss of the administered cells in the harsh, oxidative environment where these cells ought to act. Therefore we investigated if inhibition of poly(ADP-ribose)-polimerase (PARP) in these cells would lead to increased viability and subsequently to an enhanced effect.
Main methods: Ischemic conditions were simulated by oxygen and glucose deprivation for 160 min using H9c2 rat cardiomyoblast cells. After 30 minutes of reperfusion postischemic cells received 4 types of treatments: no added cells (control), fluorescently labeled untreated or PARP-inhibitor treated (10µM or 100µM PJ34) therapeutic H9c2 cells. Viability of the cells was assessed using PrestoBlue cell viability reagent and with flow cytometric analysis using live/dead fluorescent staining.
Key findings: PARP-inhibition enhanced the metabolic activity of the postischemic cells as well (H9c2: 0.635±0.043, 10µM PJ34: 0.706±0.038%, p<0.05). The survival of the added cells increased significantly with PARP-inhibition (control: 52.02±5.01%, 10µM PJ34: 63.38±4.50%; p<0.05). Importantly, the survival of the postischemic cells was also higher when treated with PARP inhibited therapeutic cells (control: 36.44±5.05%, 10µM PJ34: 52.07±5.80%; p<0.001).
Significance: PARP-inhibition improved the survival of the therapeutic cells in an in vitro cell therapy model for ischemia/reperfusion injury and increased the viability of the postischemic cells indicating that the effect of cell based therapies might be amplified if the therapeutic cells were prepared for the harsh conditions they have to face with.