How cells Divide and why do we age?
The reason is there is a fundamental cellular mechanism at the heart of aging. Do we age at the macroscopic level because our cells are aging at the microscopic level? —To a great extent, yes. There’s only a finite number of times a cell will divide.
Hayflick a biologist made a key discovery when He was studying normal human cells and found out that they can only divide a finite number of times. On average, it’s about 50 times. Beyond that limit, the cell becomes senescent, which means it’s an aged cell. It can divide no longer. And when our cells age, we age with them too. It lives for a little while but it’s the accumulation of these senescent cells in our bodies that leads to aging on the macroscopic scale.
So it’s as though cells have this little timer inside them that tells them when to stop dividing. But how do they know, and what is that timer? Telomeres are like how your shoelaces have, you know, a little bit of plastic at the end to stop them from fraying.
You can see as time passes, plastic decays and at the end there is no plastic left. Telomeres are just like these, they keep on decaying as they divide and at the end there is no telomere left.
But for chromosomes? they keep the chromosome together and they stop it from sticking to other chromosomes. So every time a cell divides, it loses some of the telomeres. They estimate about 200 base pairs.
How Can we stop Aging?
Why is that? Why can’t it just copy to the end? —You know, it’s just really the mechanics of it. You know, there’s only so much space when DNA polymerase does its job of replicating when it’s copying. So the telomere getting shorter is like your molecular clock. The cellular clock inside each cell that tells it how many times it has divided.
Wouldn’t that be fun to have your telomeres measured? Well, people do get their telomeres measured. The Healthy Fact is There have been associations made with lifestyle, with exercise, showing that longer telomeres are associated with a more active lifestyle, exercise.
But what if there was a way to stop the telomeres from shortening? If we could do that, maybe we could live forever.
There’s another enzyme involved called telomerase that you need to know, and it keeps rebuilding. Like, it doesn’t let the telomere ever shrink, so it rebuilds the telomere.
But here is the interesting part, other than animals like Hydras and Lobsters, Humans also have cells that keep on dividing. So its not really something unknown to us. And those Cells are CANCER Cells.
How are Cancer Cells Immortal?
Definitely, after reading above you would say maybe I want my telomerase to be higher for longer. Would that help? Would that keep us younger? It’s balanced, because, you know, in cancer you’ve got a perfect example of telomerase being active and it becomes an unregulated growth situation. This is the double-edged sword of telomeres and telomerase. Cancer cells have really long telomeres, and they can divide indefinitely, and that is the problem with cancer. Cancer is dividing cells that won’t stop and they won’t die. So, in a way, cancer is the immortal cell living within us.
But there is a good reason behind the limit of why our normals cells don’t divide indefinitely.
So maybe we’ve developed the aging process. Maybe we have telomeres that shorten for a very good reason because otherwise, they could become cancerous. So one of the theories there are that the cells divide that limited number of times because it stops them from accumulating damage that may be detrimental. So there is a probability It might cause them to become cancer.
So cancer cells can be researched for study in aging field and for living older and longer. Seems like Cancer cells are not all bad.