I'm going to try this again tonight. Hopefully Blogger won't act weird tonight and won't erase my post when it's most of the way done - like it did last night. I think the problem is in a new program installed into the operating system of the Blogger site. They now consider the title field to be very important, and messages will pop up every 18 seconds if you do not fill in what they now call a "required field." I don't like filling in that field, because I don't like how the titles look. I prefer the way I have been doing it up to this point. I think I know a way around this though.
With that said, on to today's post, that should have been yesterday's post, if I can remember how I worded everything last night.
The Human body is an amazing piece of machinery and a great work of art. It continually regenerates itself, which is the technical definition of healing. This is because there is an opposite force working against our bodies - increasing degeneration (a result of the 2nd Law of Thermodynamics, otherwise known as the Law of Entropy, which actually affects everything in the universe).
This degeneration is actually there all the time, from infancy to the time when our bodies finally give in to its effects, and our breath of life no longer has a valid place to live. Throughout most of our lives our regenerating abilities outweigh the onslaught of of impeti trying to degenerate us. Aging is actually (and by definition) the body's increasing lack of ability to regenerate. The organ which most visibly shows signs of this is our skin.
This is why engineers and biologists from the University of Sheffield, UK in conjunction with a team of researchers from Proctor and Gamble conducted a series of tests of that oh so visible organ, the skin. They just recently released the results of their studies in the publication "Nature Scientific Reports."
The answer to the question of "why do we age" can be found in something called "sleeping" stem cells, or rather the technical term progenitor cells residing in the skin. The real answer is actually all the things that attack our bodies, up to and including our own occasional bouts of clumsiness or carelessness. The result of these attacks, however, is our sleeping stem cells, and their reaction to these attacks, and this is where aging starts to happen.
According to their report these stem cells usually just "sleep." They do not divide and replicate like other cells. They just sit there doing nothing until they are activated. They have all the same parts as other skin cells, such as mitochondria, cell wall, nuclei with chromosomes and DNA strands, etc. They just do not divide and replicate.
When we injure our skin, whether from a small cut, a gash, a hard skin breaking bump, a tear, a smashing, or any type of burn some of the stem cells in the immediate area of injury will suddenly turn into regular skin cells. They will begin to divide and replicate just like the other cells, and this helps speed up the healing process. These progenitor cells will also activate when the pool of regular cells decreases for whatever reason.
Once a sleeping stem cell "awakens" and begins to divide and replicate it will never go back to being a stem cell. Not a single one of the replications will go into sleep mode to be saved for later. When a stem cell is used, it is used up. It's gone. This is where the phenomenon called aging comes in.
We therefore have a limited number of progenitor cells. No matter how large that number starts out as, that number is finite. It has an end. Each successive injury to our skin causes us to lose more sleeping stem cells. As we go through life we start to have less of them and less of them. This is why the older we get, the harder it is for our injuries to heal. We use up our progenitor, or sleeping stem cells.
Co-author of the project Xinshn Li of the University of Sheffield explained that another one of their findings in this matter is that individual stem cells, can be injured or stressed prior to waking up, or being activated. These injuries which happen on a cellular level can come from various chemicals, radiation, or UV light. These stressors can mutate the stem cell. While in sleep mode these mutated cells will cause no ill effects. However, when due to a normal, ordinary, run of the mill injury, or just regular depletion, one of these stress mutated stem cells activates and begins to replicate, troubles begin.
One of these mutated stem cells can start to replicate real quickly and become skin cancer. Our lungs and eyes operate in the same way. They have many (or rather start out with many) sleeping stem cells. This is why the continual onslaught from cigarette smoke is so bad. It uses up all the stem cells in the lungs, and also mutates many of them prior to their awakening.
Bones also have them. I once knew someone who raced motorcycles, and had broken some bones numerous times. After one horrific crash doctors declared that if there was another break in the same area of certain lower leg bones, that break would probably never heal. Those doctors at the time couldn't say exactly why the bone probably wouldn't heal after a fifth break of the same area of the same bone. It was just years of experience and observation that made them know that this is the case. Because of Dr. Li and all of his colleagues we can now confidently explain why this is. It is because the stem cells there are too depleted to be of much good for healing another break.
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