Unveiling the Decline of Muscle Regeneration with Age

Cornell Engineering researchers have delved into the intricacies of muscle cell regeneration decline with age by studying mice. Their work, published in Nature Aging, provides the most comprehensive portrait of how muscles' regenerative abilities change over time. The study involved sampling cells from mice of various ages, who had injuries induced using snake venom toxin. **Key Findings:** - The research identified 29 distinct cell types, notably immune cells and muscle stem cells. It was observed that immune cells and muscle stem cells behave differently with age, leading to discoordination in muscle repair in older mice. - Immune cells, responsible for coordinating tissue repair, were often out of sync in aged muscles, arriving at incorrect times or in incorrect quantities. The team employed a groundbreaking method, **transfer-learning**, for assessing cell senescence—a state where cells no longer divide. This approach assessed changes across ages and regeneration time points. The study's findings offer a template to explore the removal of senescent cells, aiming to enhance muscle repair processes in older individuals. This research, funded by the NIH and other institutions, involves several collaborators from Cornell and Johns Hopkins, emphasizing the potential of targeted therapies against cell senescence to counter age-related muscle degeneration.