Reactive Oxygen Species in Mesenchymal Stem Cell Aging: Implication to Lung Diseases

Figure 1

ROS-dependent cellular senescence pathways in MSCs. Similar to other adult somatic cells, MSCs enter replicative senescence after a certain number of cell divisions. ROS are responsible for cellular senescence and cause a direct DNA damage. DNA damage triggers a specific DNA damage response (DDR). DDR activation leads to cell cycle arrest via activation of p53/p21 and/or p16/pRB pathway. In addition, MAPK pathway is required for the acquisition of senescence. P38 plays an important causative role in cellular senescence induced by oxidative stress. Furthermore, ROS regulate major epigenetic processes and can induce DNA methylation and histone acetylation. Understanding the mechanism of senescence of MSCs should provide more effective strategies in transplantation of MSCs into the recipients with age-related diseases inherently associated with increased levels of oxidative stress.