Stem cells and hormesis

This paper summarizes recent findings on the occurrence of hormesis in a wide range of adult stem cells, embryonic stem cells, and induced pluripotent stem cells and their derived cells. These areas of biomedical and toxicological research are quite new, with the strong majority of hormesis publications for most of these stem cells being published within the last five years. Hormetic responses were typically assessed for key biological priorities of stem cells, including cell proliferation, cell differentiation, cell migration, and enhanced resilience in highly inflammatory micro-environments. The quantitative features of the hormesis dose/concentration responses of all types of stem cells were similar with respect to amplitude and width of the stimulation. This was also the case with non-stem cells. Mechanistic pathways for hormetic dose responses were commonly reported and assessed for general patterns across inducing agents, culture conditions, and stem cell types. The use of hormetic strategies can enhance stem-cell performance on multiple key parameters in an integrated manner that has the potential to impact public health. For example, it can affect exercise that targets muscle stem cells (satellite cells) to prevent or decelerate down age-related fragility, medical applications (preconditioning of stem cells that target damaged tissues, for example, following stroke or heart attack), and the expression and timing of age-related degenerative processes and diseases.