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Old Spleens Suck (2021)

sarahconstantin.substack.com

31–40 of 88 posts

Re: Old Spleens Suck (2021)

#31

Earlier quoted context omitted.

The programmed aging theory may be "obvious" but there is not really evidence to support it as of the present. If true, it would likely be very easy to stop aging (there would likely be some mechanism in cells causing aging that could simply be switched off), but this has not been borne out by research so far, and this is despite the fact that much anti-aging researching assumes it to be true. The preponderance of th…

I don’t think it is at all necessarily true that there would be one mechanism for programmed aging that could be disabled by modern medicine. Rather, evolutionary pressures might cause many mechanisms to develop simultaneously to prevent aging of individuals too far beyond the point of reproductive viability. If aging is caused by built-up damage, how would babies ever come to exist and live normal lifespans? The cel…

There's a strong filtering process. You're ignoring all the people, fetuses, embryos, and gametes that never pass on their genes.

When genomic damage gets too significant, and damage occurs to critical genes, individuals do not survive to reproductive age, fetuses are miscarried and aren't born, or embryonic development breaks and it might not even be known that fertilization occurred.

Aren't there also mechanisms that reduce accumulation of genetic damage in gametes compared to the rest of the body? That helps too.

Re: Old Spleens Suck (2021)

#33
Huh. Well, this is interesting. As someone who’s been sans spleen since age eight, all I ever heard or read about was my risk for minor bacterial infections to potentially turn into overwhelming sepsis. I was put on penicillin VK 250 mg twice a day prophylactically from the time of my splenectomy until age seventeen, when I transferred to an adult primary care physician instead of my pediatrician. I have to get the pneumovax (which protects against multiple strains of bacterial pneumonia) every five years. And I’m still constantly figuring out if I’m truly up-to-date on all my other vaccines, because some of them (like the new multiple flavors of meningitis vaccines) didn’t exist when I was younger. In short, I’ve also associated my lack-of-spleen with hypervigilance about health, and not as a potential benefit as this article posits.

Also, splenectomy led to some fun times during the pandemic because it was and is somewhat unclear whether being permanently immune-compromised due to a splenectomy applied really only to bacteria and sepsis risk, or possibly to virii like coronovairus too, since antibodies and the things that help you “clear” an infection (including a viral infection?) are also produced in your spleen. In the UK, having had a splenectomy was explicitly listed as a condition for what they called “shielding” during the worst of the pandemic, but in the US it was not considered to be a condition named for early access to a full third dose (rather than a booster) of the vaccine.

Other side effects, not mentioned in this article:

- I now have enormous tonsils, to the point where my uvula hangs at a 45 degree angle, probably because the tonsils are making up for the spleen loss, since they serve a somewhat similar function.

- As another commenter here notes, we basically only have long-term data on splenectomized people’s outcomes because of WWII. The small risk of quick sepsis is always going to be there, and did impact their lifespan. But we don’t have enough recent data, in an age of more available antibiotics, to say if there are other potential problems to look for.

- As for histamine/allergy or autoimmune issues being lessened in mice without spleens —- well, I have the same annoying allergies as everyone else in my family, take Claritin daily, and developed auto-immune antibodies due to celiac and then got the oft-associated thyroid problems. So, a sample size of one here, but a splenectomy didn’t seem to be protective against either of those immune-related outcomes here.

All that being said, I don’t miss having a spleen. It was breaking down my entire (congenitally somewhat mishapen) red blood cell supply as a kid, like a swimming pool filter run amuck, leading to anemia and exhaustion and pallor. And while removing it did not make my blood cells gain a normal shape and size, it completely changed my quality of life.

Re: Old Spleens Suck (2021)

#36

I think it is obvious at this point that the human body is designed to self-destruct, causing death at old age, once a certain biological threshold is reached. Resistance to this idea comes not from a rational perspective, but a semi-religious belief that your own body would not betray you.

>belief that your own body would not betray you

I think this is a fair point. We're multicellular life forms. We're not 1 living thing, but rather a collection of many living things working together. It could be that some of those living things start to betray each other (for personal gain) which aids in our demise. Just as individual humans can do the same to each other, leading to society's demise. But I'm not sure that means we were designed to self-destruct.

Re: Old Spleens Suck (2021)

#37
post #20

As an adolescent around 1990, I burst my spleen in the final minutes of a school ski trip. Nearly bled to death as the school staff transported me home and left me in my living room to be found later by my parents nearly unconscious. Anyway, I got to the emergency room that evening and there was much debate whether to remove my spleen. They decided not to and instead kept me hospitalized for 10 days and then out of s…

Quoted post unavailable.

At least it was related to the decision to remove a spleen or not. In at least one case I now know of, in a young patient they decided to keep the spleen.

In some cases hearing of unextraordinary events helps to calibrate what extraordinary is. I have never suffered a spleen injury, but have heard of lots of young men having theirs removed when I was younger. This anecdote leads me to believe those may have been extraordinary cases. At the very least I no longer think doctors routinely just remove spleens as I once did.

Re: Old Spleens Suck (2021)

#39
post #20

As an adolescent around 1990, I burst my spleen in the final minutes of a school ski trip. Nearly bled to death as the school staff transported me home and left me in my living room to be found later by my parents nearly unconscious. Anyway, I got to the emergency room that evening and there was much debate whether to remove my spleen. They decided not to and instead kept me hospitalized for 10 days and then out of s…

Quoted post unavailable.

Spleens are one of the more vulnerable organs. They're prone to rupture during trauma, and if ruptured, can easily cause a person to bleed out. In many motorcyclist accidents, a ruptured spleen can be the cause of death.

Spleens are essentially large bags of blood and immunological pulp, and the reason they evolved this way is because they act as a filter against bloodborne pathogens. They host a diverse but specialized collection of immune cells, such as macrophages, and have a truly unique and interesting role in overall health.

You should read up on the thymus next. That one is super important and is also implicated in aging.

Re: Old Spleens Suck (2021)

#40

Earlier quoted context omitted.

The programmed aging theory may be "obvious" but there is not really evidence to support it as of the present. If true, it would likely be very easy to stop aging (there would likely be some mechanism in cells causing aging that could simply be switched off), but this has not been borne out by research so far, and this is despite the fact that much anti-aging researching assumes it to be true. The preponderance of th…

One end of the spectrum of reasonable possibilities is that evolution selected for genes that cause and or favor death the older an organism gets, through implicit mechanisms like lack of regenerative capacity, such as heart tissue, or explicit mechanisms, of which I'm not aware of any. Are there any genes that explicitly produce a timing mechanism, and thereby create a built-in notion of aging? To my knowledge, it's…

> Are there any genes that explicitly produce a timing mechanism, and thereby create a built-in notion of aging?

Yes, telomeres.

Telomeres set a count on how many times a cell can divide before it ceases to divide and becoming old and useless; in humans, the count is 40-60 divisions and then the cell essentially dies.

There may be other timing mechanisms that haven't been discovered as well.

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