[music] >> reed pence: it's a fact of life that allof us, if we're lucky, will get old. wrinkles will set in. gray hair. and the diseases ofaging, like arthritis. diabetes. heart disease and dementia. scientists thought they'd figuredout why, according to dr. harold katcher, professor of biology at the university ofmaryland university college. >> harold katcher: it was always assumed thataging was a question of wear and tear. occurring at the cellular level, cells would, aftera time, experience wear and tear. their mitochondria would, after a time, start producing freeradicals that increased with age. the mitochondria became less efficient. dna damages were thoughtto appear in the nucleus. eventually the cells
broke down and eventually the organism diesas a result. >> pence: still, all the healthy foods andanti-oxidant vitamins in the world can't turn back the clock. but a series of experimentsphysically connecting young and old mice shows that rejuvenation might be possible. the connectionis called parabiosis. >> michael conboy: everybody is probably familiarwith the idea of siamese twins or conjoined twins where you have two individuals thatare somehow connected, but they basically share a large part of their body. so, parabiosisis basically the surgical joining of two animals to create that kind of situation. >> pence: that's dr. michael conboy, a researcherat the university of california at berkeley.
he and his wife, irina, a professor of bioengineeringat berkeley, are among the world's foremost scientists looking into factors in the bodythat might produce rejuvenation. >> conboy: in parabiosis the skin and theinner side of the two animals are surgically joined together and then when that surgeryheals the animals became basically joined as one so the blood vessels from the skinof one animal will merge with the blood vessels of the other animal and then they basicallyshare a circulation so whatever floats around in the blood of one animal and transfers over,crosses over and starts floating around the circulation of the other animal. >> pence: in connecting their circulatorysystems, old mice literally get young blood...
and their bodies start acting like they'reyounger. >> conboy: what we looked at specificallywas how does the animal regenerate after an injury. the injury we have for mice is likethe muscle injury with a little bit of snake venom, like if the mouse got bitten by a snake,probably unusual for a mouse. what we found is that the old mouse, if it’s sharing circulationwith a young mouse, that muscle regenerates much, much better and faster than it wouldif that old mouse was alone, or if it joins to another old mouse, so that it’s sharingold mouse blood instead of the young mouse. >> pence: but it doesn't take an injury forthe effects of young blood to show up. virtually every system in the body that the conboyshave looked at seems to get younger in old
mice that are connected to young ones. >> conboy: we also looked at some other organsthat are sort of representative of the different types of organs you have in the body. we lookedat liver and saw that the new liver cells forming were now improved, so there were moreliver cells being born in an old mouse liver. and we also looked in the brain and foundthat there were more neurons or neural stem cells that were being born in the memory partof the brain. this is only when sharing blood with the young partner -- much more rejuvenationof these organs than you would see by itself or sharing blood with an old animal. >> pence: other researchers have found thesame thing in experiments on mice, according
to nelson yee, founder of xvitality sciences,a firm that hopes to commercialize factors in the blood that might promote rejuvenation. >> nelson yee: we see enhancement of stemcell growth and that occurs in numerous tissues. so, it seems to occur in almost every tissuethat’s been examined. that includes the brain, there’s more neural stem cell growthin the muscles, the satellite cells become more useful, the beta cells that produce insulin,and the pancreas, they also regenerate at a faster rate. in addition to that, inflammationlevels seem to decrease and other essentially youthful characteristics re-appear in theolder animal throughout the entire body. >> katcher: when two animals were splicedtogether the maximal life span of the older
animal was increased, that is increased abovethe maximal lifespan through the maximal species lifespan. they actually had old animals thatlived some twenty percent more then the maximum lifespan. >> pence: katcher notes that the principlealso seems to work for organs, and when scientists change their environment in other ways. forexample, by transplanting an old organ such as a thymus into a young recipient. >> katcher: the thymus grows smaller withage and it turns into fat; it’s called involutes. so, the thymus involutes with age, it becomesfat and everybody assumes that is an irreversible process that’s due to wear and tear. butif you take that thymus and you place it in
the body cavity in the circulatory systemof a young animal, that involute thymus, that totally turned-to-fat-piece-of- garbage -- itbecomes functional again. its tissues again can mature lymphocytes as they could whenit was younger and it’s found that this thymus will be functional for the entire lifeof the young animal. it’s essentially doubling it’s life span aside from rejuvenating it. >> pence: however, is it really sharing bloodthat rejuvenates cells and organs? conboy says you don't really know when the entirebody is involved. it might be explained by a whole host of other factors. so severalyears ago, the conboys sought to narrow them down by taking the process outside the body...and seeing if human cells would respond the
same way. >> conboy: we had assays that we could doin a petri dish. we take muscle cells out and place them with a little bit of youngmouse blood, and those muscle cells would do their muscle thing and proliferate andmake muscles in a petri dish quite well. if you put them in a petri dish with some oldblood they didn’t do so well. so, the question was, if there’s something that’s in youngblood that’s rejuvenating, if we mix it with the old blood, we should see the rejuvenationaffect. if there’s something in the old blood that’s repressing, if we mix the twobloods together we should see a suppression of the young blood. when we mixed them togetherthe performance was like old blood, so that
meant that there was something in the oldblood that was kind of dominant and suppressing for at least these particular muscle cells. >> pence: so what's going on? the key is stemcells and their power to repair and regenerate. at one time, scientists believed that stemcells die off and disappear as an animal ages. but now we know that that's not true. conboysays stem cells are still there. but old blood is holding them back, not providing thosestem cells with the signals they need to work. >> conboy: it appears that all of our tissueshave their resident stem cells. so, in muscle there would be muscle stem cells that canmake more muscle and in the blood there are stem cells in the bone marrow that can makeblood and in different parts of the brain
there are cells that can make new neurons.my understanding is that with age, these cells, their numbers might decrease, but there arestill plenty of them there, but they don’t wake up and perform and do their job likethey did when they were young. but it looks like when we change their environment, whenyou give them signals like they would get when they were young, then that’s enoughto get them to wake up and start dividing and then make new tissue, such as you wouldneed, say, after an injury or maybe to improve the overall function of an organ. >> katcher: with their environment changedto a youthful environment, a partially youthful environment, let’s remember, [then] theydevelop the characteristics of young stem
cells, including their rate of proliferationand their ability to repair wounds -- things that, according to the theory of wear andtear, should’ve been over and gone and irreparable. >> pence: it doesn't take whole blood forrejuvenation to take place. whatever factors are at work appear to be in the plasma, theliquid portion of the blood. katcher cites the work of dr. saul villeda, now at the universityof california, san francisco. >> katcher: he actually injected plasma intoa rat. he did not remove the rat’s plasma. this was not in any way a plasma exchange;he simply injected plasma into a rat, and that rat showed significant rejuvenation ofits mental facilities, and actually its ability to form new neurons in its brain.
>> pence: scientists have found a number offactors in plasma that appear to rejuvenate cells. the conboys have identified two -- asignal protein called tgf-beta... and the hormone oxytocin. using tgf-beta, the conboyswere able to get human cells from 70-year olds to behave as if they were 50 years younger.dr. amy wagers at harvard university has found that a protein called gdf-11 can rejuvenatethe muscles and hearts of old mice. it's got a lot of people wondering if turning backthe clock isn't a pipe dream any more. >> conboy: it would be nice if some of thesetherapies would allow -- start with a mouse to live longer, and then maybe we could translateto humans so we could live longer. but i think realistically, what we definitely see is thatwe’ve improved the regeneration of tissues.
so, that’s the first therapy i can envisionfor people would be after a surgery, or an accident or something instead of taking foreverto heal, and not all that well, you’d regenerate like you did when you were a teen. >> pence: but while researchers test componentsof plasma to get to that point... others, like katcher and yee, have plans to offertransfusions of plasma itself from young people to old people. plasma transfusions have longbeen approved by the fda principally for treating coagulation disorders. but as an off-labeluse, marketing for plasma exchange programs in the united states wouldn't be allowed.so, katcher's firm, turritopsis corporation, is looking to work through clinics in southeastasia. yee's firm, xvitality sciences, is seeking
arrangements with clinics in eastern europeand south america... and trying to build up the science in studies that are as yet unpublished. >> yee: our company partnered with the universityto do a retrospective trial of around five thousand people. in our patients, the mediannumber of transfusions was three and we found some pretty positive results. there’s apositive effect for resistance to infections and also an improvement in all-cause mortality. >> pence: katcher admits we're in the veryearly stages of putting applications of rejuvenation into practice. it could be that eventually,components of plasma will be narrowed down to the very best one or two for rejuvenation.but katcher is 71 and doesn't want to wait.
>> katcher: i believe that there are alternativeways to get to the same thing. i mean, the first flying machine was a dirigible thatwas rapidly overtaken by heavier aircraft. this is perhaps a dirigible. but it will getman into the air and make it into a reality. we will be able to control aging, and ultimately,i’d like to see it so that perhaps everybody on their thirtieth birthday will have theirfirst renewal that will bring them back to their early twenties again affectively. andthat process can be repeated we don’t know how long. the sequoia tree has the optionof living thousands of years and i don’t see why we can’t have the same option. >> pence: you can find out more about allof our guests through links on our website
radiohealthjournal.net. you can also findarchives of our shows there, as well as on itunes and stitcher. i'm reed pence. [commercials]
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