Rhonda Patrick· PhD
so the the i kind of lost track of i was going to ask you something geez it was important too but oh i know what it was i had read a study i think it was one of your really good reviews that you published where you talked about bone marrow transplants yes because the question is you know there's lots of these studies coming out with parabiosis where you can transplant young blood into from you know animals into you know animals that are older and sort of have this rejuvenation effect yes um so the question is if you take cells from a younger recipient yes and put it into an older bone like a sorry if you take cells from a younger donor and put it into a older recipient so you're basically taking young cells and putting them into an older person yes so the young cells will have a younger epigenetic age obviously than what was already there yes the environment around the cells the niche so to speak yes does that play a role in does that do those blood cells like have more of an accelerated aging do they not really yeah so um just to be clear i want to distinguish peribiosis from um these um hematopoietic stem cell transplantations i can comment on both but let me start out with the hematopoietic stem cell transplantation some people have a very severe form of leukemia and therefore their bone marrow stem cells have to be removed and then and the procedure is dangerous i'll start out with that so that that's why i say only severe forms of leukemia patients get that treatment but yes let's say you take a 50 year old and you give this person a bone marrow transplant from a 20 year old and so the after the transplant the blood in the recipient reconstitutes itself the person has now new blood and the question is what's the age of the blood is that blood does the blood have the age of the 20 year old donor or the age of the 50 year old recipient and you can make a case for both scenarios but this um there are now several scientific papers that really give an unequivocal answer and which is the reconstituted blood in the recipient has the age of the donor you know and that effect persists for decades you know so if you take again the 50 year old got a bone marrow transplant from a 20 year old you follow this 50 year old 30 years now he's 80. question is how old is his blood well the age would be now 50 because 30 years have passed and you add that to the age of the donor you know and um one would think that the stem cell niche in the bone marrow you know so would could possibly affect the aging rate you know and but it just isn't the case you know and um so that's on some level a very exciting finding because it kind of hints to an idea that you could possibly rejuvenate people through transplantation you know the reason why this is not yet a viable strategy is because um people who get a transplant have often get a so-called graft versus host disease so there are all sorts of complications you know it's a dangerous procedure but in theory you know it it could work you know and talking about parabiosis um where people have um connected two mice you know where one mice mouse is much older than the other one or much younger than a mouse we just recently analyzed um peribiosis mice you know it's unpublished and we found um two um results one corroborates things and one refutes it okay but just to explain it so we looked at cortex and also subventricular zone deep white matter in the brain and we found that mice that were a young mouse that was connected to an old mouse actually aged faster according to an epigenetic clock in mice so that part confirmed these peribiosis experiments so in other words you can age a young mouse but that's not what people are interested in they're interested in the opposite you take an old mouse and you connect it to a young mouse and then you study the brain of the old mouse and you want to see that the brain is rejuvenated you know and for that scenario actually our results were disappointing we didn't see a rejuvenation effect you know and so now we're trying to get additional data because um our first study was underpowered but um one of these months we will have a definitive answer yeah for you know some of these animal studies are really good for trying to understand mechanism and yes all this data suggests you know you're you've got a a clock that can predict chronological age you've got a clock that can look at your biological age and also predict time to death lifespan yes the grim age yes and i mean something clearly is changing these methylation patterns yes so the question is what is that is there a chronic signal that's doing it or is it just completely under genetic control like what is what is and maybe they're related right so what are your thoughts what are your thoughts on the aging process and even yeah i mean um well when it comes to these epigenetic clocks this is the number one weakness of these clocks that we don't completely understand the molecular mechanism and coming back to telomere length that's a great advantage of telomere biology we really understand very well what regulates telomere length you know but yeah with the epigenetic clocks this is a very active area of research top biologists and labs are working on that very