Research Article
Peter Jorgensen and Suresh
Abstract
The Hayflick system of cellular aging and replicative senescence in vitro has been used widely in both basic and applied research in bio gerontology. The state of replicative senescence is generally considered to be irreversible, but is modifiable by genetic and environmental manipulations. Some recent observations indicate that replicative lifespan, senescence and functionality of cells in vitro can be significantly affected by the quality of the extra cellular matrix (ECM). Following up on those reports, here we show that using the ECM prepared from early passage young cells, partial rejuvenation of serially passaged human facial skin fibroblasts was possible in pre-senescent middleaged cells, but not in fully senescent late passage cells. ECM from young cells improved the appearance, viability, stress tolerance and wound healing ability of skin fibroblasts. Furthermore, young ECM modulated the oxidative stress response transcription factor Nrf-2 and its downstream effector haem-oxygenase (HO-1), possibly through the amelioration of the environmental stress induced by the plastic surface of the culturing flasks. Therefore, it is important to consider the role of ECM in modulating the response of cells both for mechanistic understanding of cellular senescence and while testing for potential aging interventions.