Yes, but a week of continual usage is chronic for a week. Its not the same as a single dose and then waiting for a week before another single dose.

I think the issue of senescent cells is an issue more for humans than mice.

This study also had the control mice not living 900 days.

image

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I agree. I do not know of any studies of a true pulsing Rapa protocol. I have zero Rapa in my blood for 1-2 weeks after every dose (which probably hangs around for a week). I won’t do more Rapa or dose more frequently until much better information arrives that says more Rapa is safe and effective for something I want but do not have.

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I think I can tell from my CGM how long Rapa is having an effect, but it will take a week or two to report on this.

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Source: x.com

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Valuable data. Given poor performance of no-rapa and strong performance of rapa alone, I’m inclined to conclude what I would consider the null hypothesis: rapa works and the others don’t.

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Based on Aubrey de Grey’s post:

Female mice benefited significantly from rapamycin in terms of longevity. Specifically, the survival curve of female mice receiving only rapamycin was almost identical to that of the mice receiving all four interventions, indicating that rapamycin was the primary contributor to their extended lifespan.

The survival curve for females receiving only rapamycin (Rapa) closely mirrors that of the group receiving all four interventions, indicating that rapamycin alone was highly effective

Anyone want to chime in? Ladies?

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Here is a post from X on my take on the latest results:

Now the first iteration of the Robust Mouse Rejuvenation (RMR) study conducted by the researcher Aubrey de Grey is almost fully completed. He has shared lifespan data on both median and maximum (90th quartile) on all treatments. The goal with the RMR study is to test different longevity experiments until we at least double the average remaining lifespan of middle-aged mice. This means that a mouse normally lives around 2,5 years but the aim is to extend their lifespan to 3,5 years with longevity treatment/s that are started at 1,5 years of age.

The thing I really like with this study is that it tries to discover powerful combinations of different longevity interventions. Why is combining interventions important? One reason for this is that with the right combination of interventions then most likely it will outperform a single longevity intervention. The tricky thing here is to find the right combination but for every new experiment that is done the field will learn, improve and increase its chances to make breakthrough discoveries that move the longevity needle. Therefore consider supporting the next iteration of the RMR study which will start this year.

Let’s take a look at the data from the RMR 1 study. In the below image you can see a toplist that I have created on the first iteration of the RMR study. The list is sorted by what works best in both genders. I have also added some additional ranking data to it around specific interventions potential as a cocktail ingredient. Here are my takeaways from this iteration.

  1. The mTOR inhibitor rapamycin seems to play a key role in several of the cocktail combinations. This data also supports my assumption why I think a mTOR inhibitor is a good base ingredient in the longevity cocktails that are engineered. I’m quite certain that there are better mTOR inhibitors than rapamycin and this is why I have been driving the project and fundraising together with Ora Biomedical around the largest mTOR inhibitor screening. This year we will get that project fully funded. Some people argue that a mTOR inhibitor is not an interesting intervention to solve aging because it just seems to just slow down the aging process. I fully agree that a mTOR inhibitor as a single intervention is not so interesting and it will not lead to any radical life extension. Maybe it can give us humans 5-15 years extra but that is just speculation. If we are going to solve aging then we need much more than that. But the very interesting thing with a mTOR inhibitor such as rapamycin, or the GSK2126458 (Omipalisib) which the Rapamycin Longevity Lab discovered last year, is their cocktail potential as a base ingredient. I would argue that it would be a big mistake to throw that potential away in the stage we currently are in. My goal is to see that we will find a better mTOR inhibitor than rapamycin and when we do that it would be great to use that compound also in future RMR iterations. Let’s see how things develop and what the data will show this year around the screening project.

  2. Some people argue that the longevity effects of different interventions are due to their effects on weight loss. Some photos of the different mice from the RMR study have been shown on conference talks by Aubrey de Grey and Caitlin Lewis and it looks like the controls without any treatment are much leaner than the treated mice (links to the talks in the comment section). The treated mice look even a bit overweight. In the conference talk with Caitlin she even confirms this by saying: “We don’t want them to be this big and some of the mice are pretty fat.” So one improvement they will do in the next RMR is to give all mice exercise wheels to decrease the risk for them to get overweight and by that the longevity effect will most likely also be even better. It would also be very interesting to improve the rapamycin arm by adding the glucose regulator acarbose to it. This is because rapamycin + acarbose is currently the best mice cocktail that the ITP (Intervention Testing Program) has discovered (pubmed: 36179270). So it would be great to continue to build combination treatments on that finding. I think that combo will also help the mice to keep a healthier weight. But regardless of what the very interesting thing that the RMR study has shown is that despite big weight gain the mice tend to live longer then no treated mice. I’m very curious to look more into this data when it is released.

  3. The gender differences in lifespan is interesting and this is also something that is seen in the different experiments done by the ITP. Currently rapamycin and calorie restriction seems to be the interventions that work really well in female mice. But so far it has been easier to find interventions that work well in male mice than in female mice. Why this is the case we don’t yet fully understand but it will be very interesting when we start to find interventions that extend female mice lifespan as well. If someone knows about an intervention that works really well in female mice please reach out!

  4. The last and more general takeaway that I started to think more and more about during last year is why the lifespan curves look like they do in different studies. In some cases median lifespan is good but not maximum lifespan or vice versa etc. This we can also see in the RMR study. One possible reason for this is that the dose regime which is used is not optimized. So if we for example see a reduction in maximum lifespan compared to median lifespan then it may be due to a too low or too high dose given late in life. I’m also doubtful that the optimal approach around many longevity interventions is to continue them until death. This is because in the late stage of life then the body is most likely in a quite fragile and broken state and I don’t believe the best thing here is for example to continue giving a mTOR inhibitor. My guess is that this pushes the body into a too catabolic state and by that it will increase the risk of a faster death. This year my plan is to write a paper around a theoretical framework which will suggest that a personalized treatment around an intervention throughout life most likely will result in better longevity effects than a fixed non-personalized treatment plan. The framework will use different biomarkers and measurements to give hints if the body is in a too anabolic or too catabolic state and where the sweet spot may be. But one big problem with animal lifespan studies is that it will be hard to implement and use this framework in a high-efficient and cost-effective way. Maybe it is easier to be used in human trials. Regardless of what the paper must be written :slightly_smiling_face:

PS 1. Visit the LEVF website for more information on how to support the upcoming RMR 2 study.

PS 2. Caitlin Lewis at Longevity Summit Dublin 2024

Aubrey de Grey at ARDD 2024

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This is speculation, perhaps right, perhaps wrong. But a couple of points. In rapamycin experiments on mice/rats (other animal models), the treatment continues until death. Yet this shows max LSE (lifespan extension). Are you suggesting that stopping the treatment at some point (old age?) would allow these animals to live even longer? That’s possible, but there is a counter argument. Namely, that even a short rapamycin treatment gives the mice almost the same benefit as lifelong (until death) exposure. But, note, crucially, not longer. I therefore find it unpersuasive that if the treatment was longer, but stopped in old age, it would suddenly make them live longer than if the treatment continued. Furthermore, you mention the mechanism that might make this shift advisable centers around mTOR. Well, CR is a potent mTOR inhibitor, and in CR experiments the animals that live the longest are on CR the longest and most severe, i.e. have their mTOR inhibited most strongly. Strike against that hypothesis.

I also disagree based on the mechanistic speculation (since we’re both speculating here!). I don’t think frailty is caused by mTOR inhibition. In fact, there are grounds to think the opposite. Rapamycin - and CR - preserve muscle function at any age (see: PEARL trial), and specifically in old age, even as an intervention against sarcopenia. Also, rapamycin is an immune modulator. Inflammaging is responsible for muscle tissue deterioration, and inflammaging leads to frailty. Rapamycin attenuates inflammaging - this is one of the primary mechanisms of operation by this drug and what is responsible in large part for its benefits. Inflammaging increases with age, and so the need for rapamycin increases with age - removing it will shorten the life of an old organism, not prolong it.

One needs to see the proper model of how frailty develops. It doesn’t develop because the body stops building muscle/bone/tissue in response to a failing signal from mTOR, and we need to increase the signal. Instead what happens is that there is less response to the signal. The mTOR is working fine and needs no boost, instead the signal is not responded to - likely in part due to systemic inflammation. We need to treat the systemic inflammation with rapamycin, CR, etc., and now the signal can get through. Also, please note - again, the PEARL trial (and other studies), just because rapamycin inhibits mTOR doesn’t mean you can’t build muscle - in the PEARL trial women on rapamycin built more muscle (and anecdotal reports from some members here seem to have the same effect). And there is no reason to think the same isn’t true for other tissues and in old people. In fact we have evidence for that - the Mannick trial… in old people rapamycin rejuvenated a whole system - the immune system (which is associated with longevity!).

Bottom line - my hypothesis is the opposite from your hypothesis. I think rapamycin is especially important in old age. I believe the evidence is overwhelmingly in favor of my hypothesis and against your hypothesis. But of course, a hypothesis must be tested, and it should be easy enough to do in mice: have two cohorts, one lifelong rapamycin and one where it is withdrawn in old age. I place my bet fully (croupier, please put ALL my chips here!) on lifelong rapamycin - maybe even increase the dose in old age😁!

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So we know at this point that both rapa and cr work predictability to extend healthspan and lifespan in mice. Further it appears that even temporary cr or rapa treatment offers such benefits. What I’m not clear about is whether these benefits/changes can be passed to offsprings and if so what are these changes - genetic? epigenetic?

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Thanks for your feedback but I think there exist some misunderstandings around my theoretical framework. I will try to clarify some things. The first thing is that death does not need to be connected to old age. As an example on what I mean I will use the lifespan curve for male mice in the first ITP study on rapamycin that was published in 2009 (pubmed: 19587680). See image below

In this image we start to see mice are starting to die even before the treatment is started. The treatment starts at around 600 days. 25% of the mice have died quite young before the treatment starts and they keep dying. It would be very interesting to see the visual appearance of these mice when they are near death. My guess is that they in most cases are quite fragile, tired and in a sick state. I don’t think they die just suddenly in a state of good wellbeing. This reminds me of my both parents who died quite recently. My father died of aggressive cancer that was not possible to treat. He lost appetite, lost lots of muscle and was in bed and tired most of the time. My mother got dementia and on top of this she broke her hip and after that the aging process really accelerated. Not so long after that she lost appetite, her happiness and was tired most of the time. I’m quite skeptical that to take rapamycin in these stages is the right thing to do. This because they for example already lost their appetite and therefore they also get mTOR inhibition from calorie restriction. So to increase the mTOR inhibition by continuing giving rapamycin I think would increase the risk of getting them in to a too catabolic state.

It is not either recommended to practice for example catabolic interventions such as calorie restriction after a surgery or fractures because that may slow down the healing process. Therefore if a mouse gets its leg broken by an accident or something in the cage then it’s most likely good to take a pause in the rapamycin treatment until things have healed in a good way. The same thing if the mouse gets very sick then it’s probably good to take a pause in rapamycin intake. My guess is that you also take pauses in your rapamycin intake if you are not feeling good or something is not right? If I would for example get a bacterial infection then I would absolutely take a pause from rapamycin. The same thing if I would get a broken leg or a severe wound or something else that signals that my body needs recovery (activation of anabolic processes).

This can also be compared to exercise. Exercise activates catabolic processes during the workout. So when we exercise and challenges are bodies then in some cases we may feel that our body really needs extra recovery time. When the body signals things like this then it’s not good to just keep pushing and not listen to the body. In the short term it may work to push the body regardless of these signals but in the long term it will have detrimental effects. So the same way we listen to our body when it comes to adjusting our exercise I think we should also adjust our other longevity protocols like rapamycin intake. Or what are your thoughts around this? Do you never do any adjustments in your longevity protocols based on different situations in your life?

So it’s not about stopping rapamycin intake fully. It’s just to take a pause if there are signals that point towards that direction.

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OK, but that’s not what you wrote in the passage I quoted. Now you are saying that if you become sick while on rapa, stop rapa. That’s a completely different thing, because what - old age itself is like getting sick, so you should stop rapa regardless in old age? Sorry, that’s incoherent. These are completely separate things. One is stopping rapa when sick - which by the way is not 100% clear in every situation, because for example we have studies showing that those who did best were the subjects who took rapa before, during and after getting a vaccine, compared to those who stopped rapa before or after the vaccine, meaning when that type of health challenge happens, it’s best to stay on rapa. Also, before surgery, it is often better to go on rapa or exercise, or low protein (mTOR inhibition), or 24/48 hour fast (mTOR inhibition) and that mTOR inhibition enhances recovery and you do better with the procedure. Now that’s not true for all situations of course, with some, like perhaps a bacterial infection, it is better to go off rapa. But that is not old age. Old age is not a condition that needs you to go off rapa or off mTOR inhibitors, we have studies showing that. Rapa and CR help with inflammaging so we keep on with rapa - now if you get sick with a bacterial infection regardless of age, so including when you are old, yes, there will be circumstances when it is better to be off rapa - but that’s a different situation than simply getting off rapa at a certain date just because you’re old. Sorry, I can’t see what your point is.

I maintain, that evidence shows that it’s best to stay on rapa, especially in old age, and only go off rapa in specific situations, such as bacterial infections - but that is true regardless of age. Otherwise stay on rapa (or other suitable mTOR inhibitors like CR). As to mice/organisms getting frail and sick early - well, they wouldn’t get sick and frail early if they were on rapa, as the graphs you posted show, so that kind of proves the point, not sure what you were trying to argue.

Rapa, early, rapa late, rapa always - at least that’s what the evidence seems to show (with breaks at times of certain health challenges).

Rapa intermittently, but not always.

You should stop Rapa in the case of bacterial infection, before surgery or after a wound which needs to heal.

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Yes, absolutely. And a reminder: rapamycin, like any drug, does not work for everyone. There will be those for whom rapamycin will be contraindicated. There is not a single intervention or drug that is good for absolutely everyone, and rapamycin is no different.

But otherwise, rapa is definitely a good thing. All we have to do is look a that graph Krister showed in his last post. That’s an argument for maintaining rapa - after all, it would be absurd to somehow suggest that those on rapa, who the graph shows benefit from rapa, should quit rapa, so they can join the graph of those who don’t get rapa and show no benefit, lol! At no point in those graphs does the “no rapa” graph cross over and outperforms the “rapa” graph. So why would you ever abandon rapa at any point, including old age??

It is especially important to keep rapamycin treatment in old age, for reasons mentioned in the paper Caveatmtor posted in the thread he started: “An aged immune system drives senescence and ageing of solid organs” where we have this quote: “These data demonstrate that an aged, senescent immune system has a causal role in driving systemic ageing and therefore represents a key therapeutic target to extend healthy ageing.” So if the pathologies of aging are caused at least in part by a senescent immune system, it is all the more important to use rapamycin to be as the quote says “a key therapeutic target to extend healthy ageing”. You want to age better, you better use rapamycin or any other agent to extend healthy aging by affecting the aging of the immune system. This is the exact, polar opposite of Krister’s hypothesis that we should abandon rapamycin as aging is equivalent in effect to a bacterial infection or recovery from surgery and healing… the exact opposite is true. Aging is not like a specific sickness or surgery recovery. Aging is a deterioration that can be ameliorated and the senescent immune system rescued by agents like rapamycin. Older=better on rapamycin.

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Regarding the quoted part then it feels like you still misunderstand me. I’m not saying because an animal or person is old then it automatically should stop taking rapamycin. And when I say late stage in life then I don’t mean old age. A young animal can die early in life without getting to a elderly stage but the late stage in life is connected to the near death phase and that phase is something everyone goes through. Even a newborn baby which in some cases may die directly and by that lives a very short life goes through this stage as well.

If we go back to my example with my parents. Do you think it would be beneficial to increase the catabolic state they were in even more? They are already in a high catabolic state as I mentioned and to increase that even more with rapamycin I don’t think is the right way.

If we also look at the example with exercise and the body which signals that it needs extra recovery time. Do you think the right thing here is to skip recovery and instead increase the catabolic processes?

The framework that I’m talking about will try to give hints around specific cases and situations based on biomarkers and other measurements if we are pushing too much on either catabolic or anabolic processes. It’s about helping out in finding the sweet spot between these two. Because the base in the framework is that an overactivation of either catabolic or anabolic processes will result in detrimental effects.

In this podcast time clip I touches a little bit more on the topic but the there are so much cover:

Here is also one image that I have started to sketch on:

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Thank you, Krister, I will listen to the video. Meawhile I would like to signal one thing that may confuse the issue here. You appear - correct me if I’m wrong - to conflate rapamycin with a catabolic state, or as inducing catabolic processes. But I don’t believe that is an accurate picture. Rapamycin can be a catabolic and an anabolic agent depending on context. The anabolic aspect is how rapamycin can allow muscle tissue growth and sarcopenia amelioration.

Regarding whether rapamycin would’ve been helpful in sick end stage of life subjects, is obviously a complicated question. Are we talking about initiating rapamycin at that point, or stopping ongoing dosage. In any case, I don’t believe the answer is obvious at all. I think it is entirely dependent on the specific morbidity. If the patient is struggling with a bacterial infection in an immune compromised condition, yes, rapamycin should be discontinued… although there is the complicated question of dosage where a higher dose suppresses some aspects of immunity, whereas a lower dose might enhance immunity - so perhaps the answer is adjust the dose (even down to zero!). Late stage dementia - unclear. It seems like there is a lot of suggestion that rapamycin might be strongly neuroprotective and AD-preventive (MK keeps asking for a trial of rapa in AD prevention!), but possibly once AD is established, rapamycin might be destructive(?).

And that graphic you sketched out at the end of your post - I strongly disagree with conceptually. The last panel starts with “accellerated aging” —> “increased risk for catabolic driven disease” —> “too much catabolism (breakdown)”. And the implication is that rapamycin in this context is a negative because it is “catabolic”. And here is where I fundamentally and profoundly disagree. Rapamycin is what is slowing down the accelleration of aging.

So my proposed graphic would be: “senescent immune system” —> “inflammaging mediated breakdown of tissue” —> “frailty”.

Many studies have shown that rapamycin rejuvenates the immune system in old people (including the Mannick study), and attenuates inflammaging. Inflammaging is a major modality of aging (which all geroprotective agents to date specifically address, according to MK!). Rapamycin slows down aging through attenuating systemic dry inflammation. Rapamycin is a break on the accelleration of the aging process.

Now you are proposing to remove the break to slow down the accelleration. This to me is totally illogical. It’s as if a car is hurtling down a steep street in San Francisco, and your remedy is to remove the break (rapamycin) to slow down the accelleration! It is exactly backwards. Which is why I said you need rapamycin more at old age. So now you say, “ok, let’s not remove the break, until the very end stage just before the crash, and then we remove it and go out in a blaze of glory!” I am completely flabbergasted by this suggestion. At no point do I see a reason to remove the break, what would be the point?? OK, I guess if you are on your deathbed, I see no reason to push rapamycin down your throat with a stick five minutes before your last breath - so there we can find grounds for agreement. Otherwise, no, absolutely not - I see your graph as confusing the cure for the disease.

But hey, it’s great to explore the issues, because they are very important - and I am very happy we can fruitfully exchange views and disagree, all in the pursuit of a common goal, health and longevity. Btw. I think your mTOR search initiative is terrific, and you are making a solid contribution to the field!

I would argue that Rapamycin does not directly cause the anabolic phase instead by increasing power levels in cells it enables cells to function more normally at a time when anabolic processes would ensure.

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There is an active discussion in another thread of astaxanthin and bone health, but rapamycin too has impact.

Here we see how rapamycin can inhibit the catabolic process (so the opposite of Krister’s thesis), exactly through the mechanism I mentioned, the suppression of inflammatory processes:

Rapamycin Inhibits Nf-ΚB Activation by Autophagy to Reduce Catabolism in Human Chondrocytes

https://www.tandfonline.com/doi/abs/10.1080/08941939.2019.1574321

" Background and Aim : Osteoarthritis is a disease that is accompanied by inflammation and catabolic disorders in the cartilage. Rapamycin is a good autophagy activator and has an inhibitory effect on inflammation, and autophagy can remove waste generated by catabolic disorders and delay the destruction of cartilage by inflammation. This study was designed to evaluate the effect of rapamycin upon the catabolism in human chondrocytes and unravel underlying mechanism. Methods and Results : C57 mice and SW1353 cells were cultured and osteoblastic arthritis was formed by destabilization of the medial meniscus surgery; 10 ng/ml of IL-1β was added to the cells to produce inflammatory chondrocytes, and a non-cytotoxic concentration of 20 nM Rapamycin was used as the self-activator. Autophagy levels were verified by quantitative analysis of autophagy markers of LC3 and ATG5, and it was verified that rapamycin can activate autophagy. Autophagy inhibition was induced by ATG5 siRNA by comparing the presence of rapamycin treatment in inflammatory chondrocytes. The expression of the degrading gene and chemokine was evaluated by qPCR. Rapamycin down-regulated the expression of MMP-3 and -9, ADAMTS5, CCL-1, -2, and -5 induced by inflammation. Quantitative analysis of IκBα and P-P65 was used to analyze the interaction between the NF-κB pathway and autophagy in inflammation. Activation of the NF-κB pathway by inflammatory stimulation, P-P65 nuclear translocation, and degradation of IκBα protein were attenuated, respectively. Autophagy inhibited the activation of NF-κB signaling pathway in inflammatory chondrocytes. Conclusions : Rapamycin can inhibit the overexpression of inflammatory catabolic genes by activating autophagy, and can suppress the NF-κB signaling pathway in chondrocytes to break the positive feedback loop with inflammatory factors and reduce the rate and level of inflammation progression."

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I would argue, however, that this is an indirect approach not a direct inhibition.

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I like tough discussions because it forces me to think more deeply about the topic so thanks for challenging me!

CronosTempi: You appear - correct me if I’m wrong - to conflate rapamycin with a catabolic state, or as inducing catabolic processes. But I don’t believe that is an accurate picture. Rapamycin can be a catabolic and an anabolic agent depending on context. The anabolic aspect is how rapamycin can allow muscle tissue growth and sarcopenia amelioration.

KK: I would argue that the common established view is that rapamycin is an catabolic activator and an anabolic inhibitor. Rapamycin inhibits directly mTORC1 and mTORC1 inhibition results in different catabolic processes.

CronosTempi: “Rapamycin Inhibits Nf-ΚB Activation by Autophagy to Reduce Catabolism in Human Chondrocytes”

KK: This is interesting but to reduce catabolism is not the same thing as activating anabolism. If we look for example at resistance training then it’s an catabolic activator. It breaks down and damages our muscle cells. The thing that happens after the breakdown is an anabolic rebound effect where the body repairs and grows the muscle bigger so that it can withstand the catabolic activation in a better way next time. So the anabolic activation afterwards is a secondary or indirect effect and not part of the direct effect as @John_Hemming points out as well.

If we also look at the potential effect of CR and rapamycin and their potential effect on decreasing sarcopenia then theories exist that it’s because of boosting autophagy in muscle which is a catabolic activation. If this makes the muscles healthier and more responsive to anabolic growth then that is again a secondary effect.

“However, recent studies have revealed that autophagy actually maintains muscle mass and that its function declines during muscle aging. Consistently, boosting basal autophagy protects from age-related muscle dysfunction by promoting the selective degradation of misfolded proteins and dysfunctional organelles. Conversely, autophagy inhibition leads to loss of muscle strength and induces a maladaptive stress response responsible for myofiber atrophy in the aged.”
Source: Skeletal muscle autophagy and its role in sarcopenia and organismal aging - PubMed

If a person also activates too much catabolism then it will have the opposite effect and instead of decreasing sarcopenia it will accelerate it.

CronosTempi: Regarding whether rapamycin would’ve been helpful in sick end stage of life subjects, is obviously a complicated question. Are we talking about initiating rapamycin at that point, or stopping ongoing dosage.

KK: Yes, it’s a complicated question but the thing I’m doubtful about is that the optimal approach is to always continue a longevity protocol. In some cases just a short pause for some time needs to be taken. It doesn’t mean that to fully stop and never take it again. If the body signals in different ways that it’s in a too catabolic state then I don’t think it’s an optimal thing to just keep pushing and activate even more catabolism. My guess is that you personally are not trying to overactivate catabolic processes or do you see that as a good state to be in? I’m very skeptical about that. Because that would mean that overactivation of catabolic processes is better than optimal activation of catabolic processes.

Regarding the immune system and Joan Mannicks research. I did a podcast interview with her one year ago where we went through her research in a quite good way. You can find it here.

But the immune system is a very complicated one and catabolism is not always beneficial. Here is a quite interesting image from a study which has tried to summarize roughly some viral infections. AMPK activation is catabolic activation.

Source: Multifaceted Role of AMPK in Viral Infections - PubMed

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