Antioxidant effect of human adult adipose-derived stromal stem cells in alveolar epithelial cells undergoing stretch

- Cyclic stretch induces an oxidative damage on human alveolar cells in vitro.
- Human adult adipose tissue-derived stromal cells (hADSCs) have an antioxidant effect in human alveolar cells undergo an injurious overstretch.
- The stretch-induced nitrative damage on alveolar cells is attenuated by hADSCs in vitro.
- Human adipose tissue is a feasible resource for adult stromal cells isolation and provides a potential clinical benefit in acute lung injury.

IntroductionAlveolar epithelial cells undergo stretching during mechanical ventilation. Stretch can modify the oxidative balance in the alveolar epithelium. The aim of the present study was to evaluate the antioxidant role of human adult adipose tissue-derived stromal cells (hADSCs) when human alveolar epithelial cells were subjected to injurious cyclic overstretching.MethodsA549 cells were subjected to biaxial stretch (0-15% change in surface area for 24 h, 0.2 Hz) with and without hADSCs. At the end of the experiments, oxidative stress was measured as superoxide generation using positive nuclear dihydroethidium (DHE) staining, superoxide dismutase (SOD) activity in cell lysates, 8-isoprostane concentrations in supernatant, and 3-nitrotyrosine by indirect immunofluorescence in fixed cells.ResultsCyclically stretching of AECs induced a significant decrease in SOD activity, and an increase in 8-isoprostane concentrations, DHE staining and 3-nitrotyrosine staining compared with non-stretched cells. Treatment with hADSCs significantly attenuated stretch-induced changes in SOD activity, 8-isoprostane concentrations, DHE and 3-nitrotyrosine staining.ConclusionThese data suggest that hADSCs have an anti-oxidative effect in human alveolar epithelial cells undergoing cyclic stretch.