The Longevity Book: Live stronger. Live better. The art of ageing well.. Cameron Diaz

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      The NIA funds research aimed at understanding ageing and improving healthy living as we age. It is also the primary federal funder of Alzheimer’s research, which consumes much of its approximately one-billion-dollar budget for research grants (1/400th of the total NIH budget is dedicated to funding ageing research). Some of that budget was spent in 2007 to kick-start the emerging field of geroscience; the NIH gave the Buck Institute, a nonprofit biomedical research center, $25 million to study ageing and its link to chronic diseases.

      When we were travelling across the country in November and December 2014 to learn about the science of ageing, we met with a group of researchers who were in the midst of publishing a collaborative paper called “Geroscience” (you can look it up and read it online in the journal Cell if you like). Their paper made a compelling argument for a new, interdisciplinary approach to ageing research.

      Its authors are a mix of highly regarded scientists. Some, like Dr Brian Kennedy at the Buck Institute, lead research initiatives for nonprofit organizations that study ageing; others, like Dr Elissa Epel at the University of California, teach and conduct research at major universities; and still others, like Dr Felipe Sierra, the director of the Division of Aging Biology at the National Institute on Aging, hold leadership positions at government-funded entities. The publication of this paper marked the first time that scientists from the private sector, academia, government, and independent organizations came together to collectively investigate a new way to study ageing. It also marked the first time that scientists from across a range of disciplines – from cell biologists to geneticists, endocrinologists, pharmacologists, and mathematicians – collaborated on this common goal.

      And the authors of the paper suggested something revolutionary: that future research should approach the various diseases of ageing as having a single shared root cause – ageing itself.

      THE OPPORTUNITY OF GEROSCIENCE

      The field of geroscience aims to understand the relationship between ageing and age-related diseases. The word root “gero” is derived from the name of the Greek god of ageing, Geras. In classical Greek mythology, most of the gods were represented as young, strong, and beautiful human-like creatures, but elderly Geras was depicted as shrivelled and small. While he may not have been as buff as Zeus, Geras – which translates to mean “gift of honor”, or “privilege of age”, or “reward” – had other attributes to offer. Because as youth flees, we gain honour, courage, wisdom, experience, and other rewards.

      The term “geroscience” feels apt as we study the new science of getting older, as Geras offers the perfect metaphor for the human relationship with ageing: a fear of physical weakening coupled with the awareness that without years, without experience, the gifts of a life well spent cannot be fully realized. Today, geroscience is attempting to reconcile these two views by investigating how we can remain strong and vital as we age.

      According to geroscientists, ageing is the biggest single risk factor for chronic illnesses like cardiovascular disease, cancer, type 2 diabetes, osteoporosis, and neurodegeneration (including Alzheimer’s). For decades, medicine has been studying the chronic diseases related to ageing separately instead of collectively. By looking at heart disease as distinct from cancer as distinct from Alzheimer’s, we miss a valuable opportunity to understand what they might all have in common. The radical question posited by the field of geroscience is: What if there were a different way to understand the process of ageing and, in doing so, alter our rate of ageing?

      Dr Gordon Lithgow, an expert in ageing and genetics who is the principal investigator and director of the Buck Institute’s Interdisciplinary Research Consortium on Geroscience, explained to us how the past revelations that have lengthened our life spans may mirror today’s discoveries about ageing. In the nineteenth century, life expectancy increased when scientists realized that many of the diseases that were killing people had a common cause. Tuberculosis, smallpox, and the flu may have looked differently and behaved differently, but they were all the result of coming into contact with tiny little organisms we couldn’t yet see. The discovery of bacteria and viruses allowed scientists to develop effective treatments for the illnesses they cause.

      The awareness sweeping science today is that the same principle may be true for the diseases of ageing. Heart attacks, cancer, and diabetes all look different and behave differently, but if we can understand their common cause, we may be able not only to live longer, but also to age with more of our health intact.

      WHAT’S THE DEAL WITH STEM CELLS?

      One new area of medicine that’s received a lot of attention recently is regenerative medicine, which uses stem cells to help heal and repair damaged and diseased organs. There’s been a lot of excitement about the potential of stem cells to heal, as well as much controversy about how they are harvested.

      There are two main classifications of naturally occurring stem cells: embryonic stem cells and adult stem cells. Embryonic stem cells have tremendous value in medical research because they have the ability to divide and become other types of cells. Embryonic stem cells come from human embryos, which contain cells that can differentiate into one of three kinds of primary cell layers (ectoderm, endoderm, and mesoderm) that have the potential to turn into any kind of cell in the body, from skin to muscle to nerve. But the practice of harvesting embryonic stem cells is controversial.

      Then there are adult stem cells, also called somatic stem cells, which live in the tissues of our organs. We now know that adults have stem cells in our brains, bone marrow, blood vessels, skin, teeth, heart, gut, liver, ovaries, and testis. These powerful cells are always at the ready to heal and repair, and have the potential to morph into other types of cells needed by the organ. Stem cells can remain dormant for a long time until they are needed to make more cells, or until a disease or injury incentivizes them to spring into action. Some adult stem cells can also be activated following exercise (as if you needed another reason to get your body moving!). The challenge of treating disease with adult stem cells is that adults have few stem cells in our tissues, and even once those have been harvested and isolated in a lab, growing more of them isn’t easy.

      Enter induced pluripotent stem cells (iPSCs). The 2012 Nobel Prize was awarded for the discovery that mature cells – normal adult cells, like skin cells – can be reprogrammed to become immature, embryonic-like cells capable of developing into specialized cells. These time-machined cells can then be used for treatments throughout the body. Since this breakthrough, researchers around the globe have been creating iPSCs and encouraging them to divide to become skeletal cells, epithelial (tissue) cells, and cardiac cells to see if they can form new bones, skin, and hearts.

      What’s so exciting about iPSCs is that they provide a way around the embryo-harvesting issues and ensure a scalable supply of adult stem cells for research and treatment. Not only that, but these cells can be derived from specific people, and so it will be your cells that are potentially made into the new cardiac cells you need after a heart failure, or your cells that make the dopamine cells you need to replace those lost in Parkinson’s disease.

      Over the coming years, we will be hearing more about the future of regenerative medicine and transplants. Scientists are very optimistic about the therapeutic potential of stem cells.

      Think about that for a moment. If ageing is the common cause of those illnesses, and we can increase our understanding of ageing at the cellular level, we may be able to live with strength and health until we die quietly in our sleep. Our bodies will weaken naturally, and ageing puts