Multi-omic rejuvenation of naturally aged tissues by a single cycle of transient reprogramming [RRBS]

The expression of the pluripotency factors OCT4, SOX2, KLF4 and MYC (OSKM) can transform somatic differentiated cells into pluripotent stem cells in a process known as reprogramming. Transient OSKM expression perturbs cellular homeostasis in a reversible manner and cycles of such incomplete reprogramming rejuvenate features of aging in cells and progeroid mice. However, little is known about the mechanisms involved. Here, we have studied changes in the DNA methylome, transcriptome and metabolome in naturally aged mice subject to a single period of transient OSKM expression in all tissues. We found that this manipulation is sufficient to rejuvenate a substantial fraction of the DNA methylation changes in gene regulatory elements that occur upon aging in the pancreas, liver and spleen. Similarly, we observed rejuvenation at the transcriptomic level, especially regarding biological processes known to change during aging. Finally, a subset of serum metabolites normally altered with aging were restored to young levels upon reprogramming. These observations indicate that a single period of OSKM expression can drive epigenetic, transcriptomic and metabolomic changes towards a younger configuration in multiple tissues and in the serum. Reduced representation bisulfite sequencing of pancreas, spleen and liver after a single cycle of transient reprogramming. Each sample represents tissue from a single mouse.