Hallmarks of Aging
The hallmarks of aging relate to fundamental biological changes that occur as we get older, and they contribute to the aging process. Think of them as the core mechanisms that make our bodies deteriorate over time. The framework of “Hallmarks of Aging” was first proposed in 2013 by scientists Carlos López-Otín and colleagues, and it has become a cornerstone for understanding how and why we age. The original nine hallmarks were extended by three more hallmarks in 2023.
The key insight of this model is that aging is not just one simple process – it’s a complex interplay of different biological changes happening simultaneously.
Here are the 12 hallmarks:
Over time, our DNA accumulates damage from environmental factors and from natural processes. Think of DNA as an instruction manual that gets worn and torn. Things like sunlight, chemicals, and normal cell processes (e.g. replication errors) can damage it. While our cells have repair tools, they become less effective as we age. The accumulation of mutations can affect gene function and cellular behavior
The protective caps at the ends of our chromosomes (telomeres) get shorter with each cell division, eventually leading to cellular aging. Imagine telomeres as the plastic tips on shoelaces. Each time a cell copies itself, these tips get shorter. When they get too short, the cell either stops working properly or dies
Changes in how our genes are expressed (turned on or off) occur with age, affecting cell function. Think of your genes as a recipe book. Epigenetic changes are like sticky notes that tell the cell which recipes to use or ignore. With age, some of these sticky notes get mixed up
Our cells become less efficient at maintaining and recycling proteins, leading to accumulation of damaged proteins. Like a messy room that gets harder to clean, old proteins build up in cells. The cell’s cleanup and recycling systems become less effective, leading to cellular “trash” accumulation. Misfolded proteins and protein aggregates can form toxic assemblies
With age, the body becomes less effective at detecting and responding to nutrients, affecting metabolism. It’s like developing “food blindness” – cells become less good at noticing and properly using nutrients, similar to how some people become less sensitive to insulin in diabetes
The power plants of our cells (mitochondria) become less efficient, reducing cellular energy production. Mitochondria are like tiny batteries in our cells. As they age, they produce less energy and more waste products, like a worn-out battery that does not hold charge well
Some cells enter a zombie-like state where they no longer divide but release harmful compounds. Instead of dying normally, some old cells stay alive and release harmful chemicals that inflame and damage surrounding tissue
Our body’s supply of regenerative cells diminishes, reducing tissue repair capacity. Stem cells are like the body’s maintenance crew. Over time, we have fewer of them, and the remaining ones do not work as well, making it harder for the body to repair damage
Cells become less effective at communicating with each other, disrupting bodily functions. Messages between cells become garbled or lost, leading to poor coordination of body functions
A persistent low-grade inflammation develops throughout the body, damaging tissues. It is like having your immune system stuck in “low alert” mode all the time, slowly damaging tissues
An unhealthy imbalance develops in your gut microbes (the trillions of bacteria and other microorganisms living in your digestive system). As we age, the diversity and types of beneficial microbes often change for the worse, which can affect everything from our immune system to our brain health. Think of it like a garden where the helpful plants are gradually being overtaken by less beneficial ones
When your body’s cell recycling system stops working properly, this is called altered autophagy (which literally means “self-eating”). As we age, the process of how cells break down and recycle their old or damaged parts becomes less efficient – imagine a cleaning crew that’s getting slower and sloppier at removing trash and reusing materials. When autophagy does not work well, damaged proteins and cellular components build up, which can lead to various age-related problems
These hallmarks form a complex network of interactions. For example:
- DNA damage can trigger cellular senescence
- Senescent cells contribute to inflammation
- Inflammation can cause further DNA damage
- Mitochondrial dysfunction increases oxidative stress, leading to more DNA damage
- Proteostasis loss can affect mitochondrial function
- Epigenetic changes can alter stem cell function
These interactions create feedback loops that can accelerate aging. Understanding these connections is crucial for developing interventions that might effectively target multiple hallmarks simultaneously.
The significance of these hallmarks for longevity research is profound. They provide scientists with specific targets for interventions that might slow or reverse aging. Ideally, finding ways of addressing all hallmarks of aging simultaneously can affect the speed of aging and contribute to longevity.
Understanding these hallmarks has helped shift the perspective on aging from an inevitable, uncontrollable process to one that might be malleable through medical intervention. This has important implications for how we might treat age-related diseases in the future, potentially addressing them at their root cause rather than just managing symptoms.
Nutritional supplements (next to lifestyle choices around exercise, good sleep and proper nutrition) may play a significant role in helping you address the hallmarks of aging. Juvina Bioscience has developed products that address all hallmarks of aging.