The end of aging (and the seven deadly damage)

Indefinite youthfulness is typically one of the most common subjects of discussion among transhumanists, and is probably one of those which is mostly displayed in media. Traditional transhumanists will usually argue that such a feat would be best achieved through cybernetics, slowly replacing our bodies with machines until our mind run from a super computer that can be fixed by any specialist in electronics, and therefore has the potential to stay functional indefinitely as long as proper maintenance and backup is performed. This vision tends to forget that the human body is in itself a formidable machine, and that aging is not as mysterious as it once was. Typically, when it comes to aging, the scientific understanding of how aging damages the body and brings us closer to death is relatively well understood. Aging basically causes seven types of damage to the body. These types of damage are not controversial in and by themselves, although scientists might argue about the relative importance of them in degenerative aging, it remains that all these signs are found in older bodies and are absent from youthful ones. All of these seven types of damage have potential treatments that could be merely a few decades away with proper funding and all of them are targeted by the SENS research foundation project, on which I will come back later.

1. Extracellular junk: It’s basically the stuff that accumulates outside your cells and that your body can’t get rid of. One of the best known effects of this type of accumulation is Alzheimer’s disease, which has been speculated to be mostly the result of an accumulation of proteins around the neurons, which cause them to die, with all the consequences that come with such a result. This accumulations also happens in normal aging and could play an important role in the normal decline of cognitive functions that comes with aging. This type of damage could be solved with a vaccine that could train the immune system to recognize the offending proteins and get rid of them.
2. Intracellular junk: Well… it’s pretty much the same as extracellular junk, but inside the cell. The lysosome is the organelle inside the cell that is normally responsible of clearing the innards of a cell, but sometimes, it just can’t process some types of waste products. The waste will then start accumulating inside the cell, which will impact its functioning and can even make it harmful to the rest of the body. Think of atherosclerosis, which is composed of immune cells that just can’t digest their last meals and start accumulating in the arteries, forming clogs. One solution to this phenomenon is to inject enzymes into the patient’s body, which would be delivered inside the cell to clear the waste and restore it to function.
3. Extracellular crosslink: This basically happens when the proteins that build all the supports for our cells start bonding with sugars and become more stiff and breakable. This is the kind of damage that causes arterial stiffening which can lead to strokes or other vascular problems. Such types of damage could be targeted by a chemical that aims to undo the bonds and restore flexibility to membranes.
4. Cell loss and atrophy: It’s probably one of the best known damage that comes from aging, which is the loss of stem cells in the body. As they age, cells progressively lose their ability to replicate, which eventually make it impossible for them to replenish the body with fresh cells. Other cells just don’t replicate a lot in the first place and therefore cannot be replaced once they start aging and malfunctioning. This type of damage causes some of the most visible signs of aging, such as the loss of muscle mass and the malfunction of organs. The solution for such a problem is pretty popular these days: Stem cell therapy. It basically consists into turning any cell in the body into a stem cell, which can then be matured into any cell we need to replenish the body with a fresh supply.
5. Death resistant cells: This one might seem counter-intuitive, but the body needs its cells to die on a regular basis to be able to keep working. This process, called apoptosis, allows for old cells to give their place to younger fresher cells to take their place. An example of this process would be the degeneration of the immune system as we age, which start being cluttered with memory cells that aren’t actually doing anything good for the health of the body. Simply clearing those cells out by sending them a targeted chemical messenger that tells them to go into apoptosis would do much to restore function to the rest of the immune system, by allowing new immune cells to take over and start recognizing the new treats. Such treatment could be used on any senescent cell population and could obviously be very efficiently be combined with stem cell therapies to replace them with younger cells.
6. Cancerous cells: Another type of damage that happen to the body is the inclusion of mistakes in the DNA, mutations. Mutations are typically irrelevant in normal aging except in one aspect: Cancer. When a piece of miswritten code leads to anarchic reproduction of one cell, all hell breaks loose and the growing population of dangerous cells can soon become a threat to the whole organism. Research on cancer treatments is already well funded, but should the ever more novel types of therapies to target and destroy cancer fail, there would still be the option to alter our DNA so that it simply became impossible for cells get into this anarchic reproductive state. The downside of this procedure would be that all fast reproducing cells would be affected, which would cause a complete dependency on stem cell therapies. However, this would be a fair price to pay to be completely rid of cancer, especially if stem cell therapies are widely available and used as a treatment against aging anyway.
7. Mitochondrial mutation: This type of damage, and its role in degenerative aging, is more controversial and less understood. Mitochondria are basically the furnace for our cells, responsible of transforming sugars into usable energy. As an organelle, the mitochondrion’s got its own DNA, passed on by the mother’s mitochondria in the egg cell. As we age, this DNA can become damage, which can lead to a malfunction of the “furnace”. Since this furnace works by combine sugar and oxygen to produce CO2 and energy, malfunctions means that it’s going to start throwing reactive oxygen, or oxidizers, all around the place. While the process through which this becomes important in overall aging is still controversial, it remains that these molecules of reactive oxygen have the potential to do a lot of damage in the body. While this effect is one of the reasons behind the popularity of “antioxidant” supplements, the effect that these might have on aging is poorly understood and probably largely useless in actually preventing degenerative aging. A more functional solution would be to implement a genetic therapy that would provide the broken mitochondria with fresh proteins that could replace those that the defective DNA couldn’t produce, which would repair the “furnace” and insure that oxygen stays where it is needed.

This list of damage is an exhaustive one, considering what we know of the human body. While there is a lot of debates about the specific molecular processes of how this damage happens and the all the pathways involve, fixing this damage would be a simple engineering problem which wouldn’t require us to know everything about the biochemistry of it all. Sadly though, most of the research that has been done in aging has been focusing on accumulating knowledge about the intricate biochemical details in the hope of someday tinkering with it in the hope of making it more efficient. But this approach is long and costly, and people are still dying of old age by the millions in the meantime. Furthermore, even the best machine wears out, and therefore the priority should go to the knowledge of how to fix it in the first place. The only organisation that embraces this approach is the SENS research foundation, a private initiative by Aubrey de Grey who has been working on this for more than a decade now. If such research were to become mainstream, it could be feasible that our own generation could see the advent of regeneration therapies that would allow us to reach indefinite youthfulness.

Sources:

A great introduction to the SENS research foundation project! Don’t forget to donate and share the idea!

http://www.sens.org/research/introduction-to-sens-research

A daily source of information for research on degenerative aging and longevity.

https://www.fightaging.org/

Aubrey de Grey’s book about his SENS project

De Grey, A., & Rae, M. (2007). Ending aging: The rejuvenation breakthroughs that could reverse human aging in our lifetime. Macmillan.