Transient non-integrative expression of nuclear reprogramming factors promotes multifaceted amelioration of aging in human cells

Tapash Jay Sarkar,Linda Doan,Shravani Mukherjee,Vittorio Sebastiano,Christopher M Tran,Constance R Chu,Nidhi Bhutani,Alex Colville,Patrick Paine,Marco Quarta,Steve Horvath,Lei S Qi,Thomas A Rando

doi:10.1038/s41467-020-15174-3

Abstract

Aging is characterized by a gradual loss of function occurring at the molecular, cellular, tissue and organismal levels. At the chromatin level, aging associates with progressive accumulation of epigenetic errors that eventually lead to aberrant gene regulation, stem cell exhaustion, senescence, and deregulated cell/tissue homeostasis. Nuclear reprogramming to pluripotency can revert both the age and the identity of any cell to that of an embryonic cell. Recent evidence shows that transient reprogramming can ameliorate age-associated hallmarks and extend lifespan in progeroid mice. However, it is unknown how this form of rejuvenation would apply to naturally aged human cells. Here we show that transient expression of nuclear reprogramming factors, mediated by expression of mRNAs, promotes a rapid and broad amelioration of cellular aging, including resetting of epigenetic clock, reduction of the inflammatory profile in chondrocytes, and restoration of youthful regenerative response to aged, human muscle stem cells, in each case without abolishing cellular identity.

Highlights

Aging is characterized by a gradual loss of function occurring at the molecular, cellular, tissue and organismal levels
We first evaluated the effect of transient expression of reprogramming factors on the transcriptome of two distinct cell types—fibroblasts and endothelial cells—from aged human subjects, and we compared it with the transcriptome of the same cell types isolated from young donors (Fig. 1a, e)
Our protocol consistently produces induced pluripotent stem cells (iPSCs) colonies, regardless of age of the donors, after 12–15 daily transfections; we reasoned that the PNR in our platform occurs at about day 5 of reprogramming, based on the observation that the first detectable expression of endogenous pluripotency-associated lncRNAs occurs at day 58

Summary

Introduction

Aging is characterized by a gradual loss of function occurring at the molecular, cellular, tissue and organismal levels. Results We first evaluated the effect of transient expression of reprogramming factors on the transcriptome of two distinct cell types—fibroblasts and endothelial cells—from aged human subjects, and we compared it with the transcriptome of the same cell types isolated from young donors (Fig. 1a, e).

Results

Conclusion