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Clear senescent cells

Senescent Cells

Nina Khera
Nov 5, 2018 · 5 min read


Have you ever found a patch of dry skin? Has one of your older relatives ever gotten diabetes? Had kidney failure?

These are caused by senescent cells. Senescent cells are the undead cells in our body that are one of the causes of a ton of diseases, including cancer. These are important because since we have these, we’re prone to tons of sicknesses.

What are senescent cells?

To figure that out, we would have to start with cell division. In your body, cells divide all the time. A mere second means 2 million new cells. But there’s more!

Every time a cell divides, it has to copy its chromosomes. Of course, this process is not perfect, so they lose a tiny bit of DNA at the ends, which could be catastrophic. To protect our DNA, we have small segments of DNA at the ends called telomeres, and this is DNA that is dispensable, which lets the cell divide about 50–70 times.

Think of telomeres as the plastic bits at the ends of shoelaces (aglets). They slowly fray, and in this case, after a while of division, they’re gone. When they’re gone, the cell is damaged.

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Telomeres, the aglets of the chromosome.

You would think that the cells would die, right? Wrong. They stick around and release harmful chemicals into your body. Now, by harmful, I don’t mean poisonous, or ‘you’re going to die in the next week’ harmful, because if so, we’d all die within a few seconds of being born, and I wouldn’t be writing this.

Those are senescent cells. Half dead cells that do absolutely nothing beneficial but release chemicals that bring you sickness, and slowly kill you by harming the tissue around them. The reason they don’t die is that they underproduce a protein that tells them when it’s time to die.

How do we identify senescent cells?

There are a few markers, but no senescent cells display all of them, and no markers are exclusive to senescent cells. This is why they’re defined by a lot of characteristics. One of the defining characteristics is arrested growth. Some smaller are that they typically enlarge, sometimes to the point where they double in volume, and if it does that, it takes on a flattened morphology.

Ways to get rid of them

Now, you’re probably thinking : ‘Why don’t we perform some sort of procedure to get rid of them?’ This has actually been tried on mice. Older mice without these cells were more active, their hearts and kidneys were better, and they were less prone to cancer. Overall, they lived 30 percent longer.

The only problem with this, is that the subjects were mice. This wouldn’t necessarily work on humans. Plus, how would we remove the cells? Back to the lack of protein, mice have been injected with this protein (study in late 2016) and it killed 80% of senescent cells while harming almost no healthy cells.

The problem is these studies have been carried out on mice, and there isn’t any guarantee that this would work for a regular person, but these are proof of concepts. To learn more about this, we need human trials to develop a possible way to eradicate senescent cells.


There is another thing being researched, and it goes by the name of senolytics. They’re molecules under research to see if they can cause the death of senescent cells without killing the healthy ones.

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Types of senolytics : QUERCETIN and DASATINIB and their compounds

The problem with this is it’s still being tested, and isn’t necessarily fully safe, and it would have to be a procedure. This would create a large privilege gap, because only families who would be able to afford it would be able to procure this treatment.

What we can do

You may be wondering : ‘How can I get rid of my senescent cells in my daily life?’.

There are a few different ways to eradicate senescent cells on our own. Plant compounds and fungus or fasting activate an immune system (autophagy) which recycles damaged cell parts. This is one of the many ways to eradicate senescent cells.

Autophagy is a system that destroys cells in the body. It maintains homeostasis or normal functioning because of protein degradation and repurposing of the destroyed cells to form new and better cells. During cellular stress the process of Autophagy is increased by a lot.

Now, you may be thinking that this is your answer to living forever, or at least way longer. Wrong. Senescent cells are merely a puzzle piece in the entire scope of longevity. There are stem cells, NAD+, free radicals, and more.

If you read this in hopes of living longer, don’t fret. Research shows your lifespan can be increased by lifelong friendships, tightly knit communities, and long term marriage.

You may be wondering ‘How would this help you live longer?’, this helps lengthen your telomeres. Longer telomeres let your cells divide an increased amount of times. This means less senescent cells, and therefore it helps you live a bit longer.

The reason it lengthens your telomeres is telomerase. Telomerase is a ribonucleoprotein that adds a bit of length at the ends of your telomeres. Things such as stress, an unhealthy diet, little to no exercise, and a bad environment decrease your telomerase.

Key Takeaways

  • Senescent cells are ‘zombie cells’
  • They can be removed through various methods yet to be tested on humans
  • If you want to remove them yourself, initiate autophagy
  • Things that’ll help you live longer are lifelong friendships, tightly knit communities, and long term marriage

I hope this article helped you, and don’t forget to clap it if you liked it!

If you wanted some additional resources :

Those are both great, although the first one is a bit complicated, so if you’re looking for a beginner level article, read the second. If you’re looking for a more in depth paper, read the first.

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