The Science of Aging: Part 2 – A brief review of the last decade of research

Lopez-Otin et al; Cell (2023)

Aging research has taken some exciting turns over the past decade. As someone very curious about this field, I've been particularly impressed by a subset of groundbreaking papers. In this article, I provide a concise summary of these key studies to give you a clearer picture of the current breadth and depth of aging research, while acknowledging that there are numerous other excellent papers out there making significant contributions to the field. Each of these reviews and studies offers a unique lens on aging - from the cellular level to whole organs. Additionally, I've discovered a resource that sheds light on the challenges still facing aging research. Let’s dive in!

Hallmarks of Aging

Lopez-Otin et al., Cell (2013 & 2023)

This group has published two comprehensive reviews is a cornerstone in aging research. They identified nine key hallmarks (which was expanded to twelve hallmarks in 2023) that are common in aging across different species. The papers not only list and discuss the details of these factors -- genomic instability, telomere attrition, epigenetic alterations, loss of proteostasis, deregulated nutrient-sensing, mitochondrial dysfunction, cellular senescence, stem cell exhaustion, dysbiosis, chronic inflammation, disabled macroautophagy, and altered intercellular communication -- but explore their interconnectedness and potential as targets for aging-related treatments. As we have seen before, they draw a parallel between cancer and aging, suggesting a shared origin: the accumulation of cellular damage. These reviews are essential reads for anyone looking to get a grasp on the fundamentals of aging!

Aging using Single-cell omics

He X. et al, Nature Metabolism (2020)

Moving to a more microscopic level, this paper showcases how single-cell sequencing is revolutionizing our understanding of aging. It's like having a microscopic lens zooming into each cell, revealing how they change with age. Techniques like single-cell RNA sequencing and CRISPR-Cas9 genome editing are used to track these changes. The study provides insights into how different cells, such as brain cells and blood stem cells, age distinctly. It also explores how lifestyle factors, like diet, can influence cellular aging processes. The complexity and potential of single-cell technologies in aging research are truly astounding.

Organ-Specific Aging Signatures

Hamilton Oh et al, Nature (2023)

Hamilton Oh's study takes a broader view, examining how different organs in our body age. It's fascinating to see that aging doesn't happen uniformly across our body. By analyzing blood plasma proteins, the study predicts the aging rate of various organs and relates it to health conditions. For instance, the predicted age of the heart can indicate the risk of heart attack. This approach exemplifies the creative use of existing data to unravel complex questions about aging and health!

Unanswered Questions in Aging Research

In addition to these studies, the 'Longevity Bottlenecks' report by the Longevity Biotech consortium is an eye-opener on the ongoing challenges in aging research. It highlights how perspectives on these challenges vary across different roles in the field, from academics to principal investigators. A common theme is the urgent need for more accessible data to advance our understanding of aging.

As we delve into these fascinating areas of aging research, it's clear that this journey is as complex as it is intriguing. Each study opens up new vistas of understanding while also raising many new questions. I'm excited about the future of aging research and the potential breakthroughs the next decade might hold.

Sources*:

• Florea et al. Longevity Bottlenecks. bioRxiv. (2023) doi: 10.1101/2023.08.18.553936

• He X et. al. Single-cell omics in ageing: a young and growing field. Nat Metab. (2020) doi: 10.1038/s42255-020-0196-7.

• López-Otín et. al. The hallmarks of aging. Cell. (2013) doi: 10.1016/j.cell.2013.05.039López-Otín C, Blasco MA, Partridge L, Serrano M, Kroemer G. Hallmarks of aging: An expanding universe. Cell. (2023) doi: 10.1016/j.cell.2022.11.001

• Oh HS et. al. Organ aging signatures in the plasma proteome track health and disease. Nature. (2023) doi: 10.1038/s41586-023-06802-1.

*Note: For a full list of authors and references please see these articles and their citations.