But scientists are working hard to stop them once and for all.
Aging is mankind’s most powerful enemy. If nothing else gets you, time certainly will.
Or will it?
That’s the way it’s always been, but research to radically extend the lifespan of human beings is underway, and making serious progress. There are only seven problems that need to be solved before aging is defeated.
1. Cell Depletion - As human beings age, we lose cells in important structures such as the heart and the brain. Sometimes the gaps cause nearby cells to enlarge, sometimes they are filled by other types of cells or fibrous acellular material. Stem cell therapy is vital to solving this problem.
2. Cell Toxicity - This is the opposite of the cell depletion problem, when unwanted cells accumulate in areas such as visceral fat, cartilage in joints, and in the immune system. Targeting molecules on the surface of these cells to destroy them and gene therapy combined with stem cell research will likely lead to the solution.
3. Chromosomal mutations and epimutations - Our cells divide a lot and DNA mutations can be very dangerous. Cancer is one such problem. However, evolution has developed some very sophisticated systems for DNA maintenance-good thing too, because otherwise we’d all die of cancer very quickly.
The main problem here is telomere shortening. Each time a cell divides its DNA is replicated and the ends of the chromosome lose a small amount of DNA. After a while this causes problems. Erasing the enzyme telomerase and shutting down the ALT system (Alternative Lengthening of Telomeres) with gene therapy and stem cells would take care of this.
4. Mitochondrial Mutations - The mitochondrion is the cell’s power plant, tasked with cellular respiration and generating ATP, a source of chemical energy. Mitochondria have their own DNA, and the inevitable accumulation of mutations causes this engine to malfunction and shut down.
Mitochondria require a thousand different proteins, each encoded by a different gene, but most of the work is done by the DNA in the nucleus and transferred to the mitochondrion via the TIM/TOM complex. Only 13 of the mitochondrion’s proteins are encoded by the mitochondrion itself. With gene therapy we will be able to make modified copies of these 13 genes and put them into the chromosomes in the nucleus. Chromosomal DNA is much better protected against mutation than mitochondrial DNA, so we take the job of manufacturing these proteins away from the mitochondria and give it to the chromosomes.
5. Intracellular junk - Cells have to break down big molecules and structures into component parts, often because they have become chemically modified in such a way that they are no longer useful. But every now and then the chemical modification creates structures that the cell can’t break down. The lysosome is a special cellular organelle that contains the cell’s most powerful degradation machinery, and if it can’t break down something, that junk just stays there forever. In non-dividing cells, the junk accumulates and becomes a serious problem. The solution is to provide the cells with specific enzymes targeted to break down the material.
6. Extracellular junk - This is similar to intracellular junk, except it occurs outside the cells. A large part of the problem will be solved by making the intracellular degradation machinery more powerful. But amyloid is a whole other problem. Amyloids are fibrous protein aggregations that accumulate in the brain. Small peptides called beta-breakers may be used to dissolve this plaque, or the immune system may be stimulated to attack it and break it down.
7. Extracellular protein crosslinking - Proteins inside our cells are regularly destroyed and rebuilt. This recycling keeps them undamaged. Proteins outside the cells, however, are often recycled very slowly or not at all. Chemical reactions will cause a bond between nearby proteins. In this way, the skin loses elasticity and the arterial walls become rigid. These cross-linked proteins are very unusual chemical structures, so they can be highly targeted by specific chemicals that will react with the cross-links and break the bonds without damaging or reacting with anything else.
So there you have it. Seven problems to solve and aging will be a thing of the past. Humans will have indefinite youthful lifespans.
How soon will these problems be solved? That depends on public awareness and support. You can help. Become knowledgeable, spread the word, and join with others to advance the cause. Let our politicians know that this is a project deserving of financial support, and that stem cell research is vital.
Here are a few links for more information:
SENS.org (Strategies for Engineered Negligible Senescence)The Methuselah Foundation
MPrize
The Immortality Institute
The Longevity Meme
Fight Aging!
Extropy Institute
Lifeboat Foundation
Maximum Life Foundation
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