{"id":444,"date":"2015-11-19T22:22:40","date_gmt":"2015-11-19T22:22:40","guid":{"rendered":"http:\/\/joshmitteldorf.peachpuff-wolverine-566518.hostingersite.com\/?p=444"},"modified":"2015-11-22T21:43:47","modified_gmt":"2015-11-22T21:43:47","slug":"anti-aging-medicine-two-paths-diverge","status":"publish","type":"post","link":"https:\/\/scienceblog.com\/joshmitteldorf\/2015\/11\/19\/anti-aging-medicine-two-paths-diverge\/","title":{"rendered":"Anti-Aging Medicine: Two Paths Diverge"},"content":{"rendered":"<figure style=\"width: 310px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/images.rapgenius.com\/3a78119a78c1de70b4374b9787862ef0.320x246x1.jpg\" alt=\"\" width=\"320\" height=\"246\" \/><figcaption class=\"wp-caption-text\">&#8230;and sorry I was I could not travel both.<\/figcaption><\/figure>\n<ul>\n<li><b><i><b><i>Aging is an accumulation of damage. \u00a0If we want to return the body to a more youthful state, we\u2019re going to have to repair that damage.<\/i><\/b><b><i><br \/>\n<\/i><\/b><\/i><\/b><\/li>\n<\/ul>\n<ul>\n<li><b><i>The body never forgets how to be young. \u00a0Given the appropriate signaling environment, the body will restore itself to a youthful state.<\/i><\/b><\/li>\n<\/ul>\n<p>The future of medicine is the future of anti-aging medicine. \u00a0I don\u2019t think anyone seriously disputes this. \u00a0Infectious diseases are a minuscule problem compared to a century ago, and with hygiene, good public health practices, and responsible restraint in applying antibiotics, we may hope to avoid a return to the days when tuberculosis and syphilis were pandemic. \u00a0We are fast learning to treat congenital disorders, and safe gene therapies are already being tested.<\/p>\n<p><span style=\"font-weight: 400\">This leaves diseases of old age as the next frontier. \u00a0To slow the progress of aging, there is no doubt that signaling approaches work in animals, and will work (probably with less efficacy) in humans. \u00a0Caloric restriction (CR), exercise and other forms of hormesis are the best approaches we know at present. \u00a0Pills (e.g. <\/span><a href=\"https:\/\/scienceblog.com\/joshmitteldorf\/2012\/11\/26\/is-metformin-an-anti-aging-drug\/\"><span style=\"font-weight: 400\">metformin<\/span><\/a><span style=\"font-weight: 400\">, <\/span><a href=\"https:\/\/scienceblog.com\/joshmitteldorf\/2015\/10\/13\/can-botanicals-replace-metformin\/\"><span style=\"font-weight: 400\">berberine<\/span><\/a><span style=\"font-weight: 400\">) may offer some of the benefits of CR without the hunger, and an \u201c<\/span><a href=\"http:\/\/www.smithsonianmag.com\/innovation\/scientists-are-working-pill-just-might-replace-exercise-180956910\/?no-ist\"><span style=\"font-weight: 400\">exercise pill<\/span><\/a><span style=\"font-weight: 400\">\u201d has been proposed. <\/span><\/p>\n<p><span style=\"font-weight: 400\">The next step is to actually reverse aging, to restore the body to a more youthful state. \u00a0Among those of us who advocate research in the technology of age reversal, there are two prevailing paradigms. \u00a0I am with the school that says the same signaling approach can be extended to trick the body into thinking it is younger than it is, and the body will renew its cells and replace damaged biomolecules on cue. \u00a0The other school says that once the toothpaste is out of the tube, it\u2019s not going back in. \u00a0We will have to engineer prosthetics, use bioengineering and regenerative medicine to replace body parts that have worn out.<\/span><\/p>\n<p style=\"text-align: center\"><b>Theory<\/b><\/p>\n<p><b>\u201cEverything degrades over time&#8211;it\u2019s basic physics\u201d<\/b><\/p>\n<p><span style=\"font-weight: 400\">This is just wrong, but it\u2019s so prevalent (among gerontologists and the great unwashed masses alike) that I\u2019ll refute it yet again: \u00a0There is no physical necessity for aging. \u00a0Analogies to wearing out and to chemical corrosion are flawed and misguided. \u00a0The body may accumulate more damage than it repairs; but it may also repair more damage than it accumulates. \u00a0The choice is made by the metabolism (as programmed by evolution), not by physics.<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">The Second Law of Thermodynamics is specifically about closed systems, meaning systems that don\u2019t interact with the outside world. \u00a0But living beings are evolved to take in order from food or sunlight and dump entropy back into the environment. \u00a0All of life is an end run around the Second Law.<\/span><\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">Still, some people say the \u201cend run\u201d has to come to an end some time. \u00a0How can repair be \u201cperfect\u201d? \u00a0Well, it doesn\u2019t have to be perfect. There is nothing perfect about a 20-year-old body, and it is the body\u2019s metabolic choice whether to build itself ever stronger, more resilient and less vulnerable to disease, or allow it to decay, or (in between) to maintain a constant level of youthful robustness indefinitely.<\/span><\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">&#8230;and indeed, some animals and many plants <\/span><b><i>do<\/i><\/b><span style=\"font-weight: 400\"> go on getting stronger and larger, with lower and lower mortality risk, year after year after year. \u00a0This is called <\/span><a href=\"http:\/\/www.ncbi.nlm.nih.gov\/pubmed\/15136009\"><span style=\"font-weight: 400\">negative senescence<\/span><\/a><span style=\"font-weight: 400\">, a fancy word for aging backwards. \u00a0Most trees do it, as well as lobsters, clams, some turtles, and possibly sharks and whales. <\/span><\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">If physics demanded that living organisms always degrade then growth and development would be impossible.<\/span><\/li>\n<\/ul>\n<p><span style=\"font-weight: 400\">Evolutionary biologists almost all appreciate this&#8212;aging is a problem for evolution, not for physics. \u00a0Though many of the symptoms of old age may look like accumulated damage, there is no <\/span><b><i>necessity<\/i><\/b><span style=\"font-weight: 400\"> for the damage to accumulate; the body is making a choice to repair the damage only partially, as opposed to rebuilding better-than-new, which is perfectly possible, both physically and biologically. <\/span><\/p>\n<p><span style=\"font-weight: 400\">More detail is <\/span><a href=\"https:\/\/scienceblog.com\/joshmitteldorf\/2014\/04\/07\/no-the-body-doesnt-just-wear-out-as-we-get-older\/\"><span style=\"font-weight: 400\">in my blog post from 2014<\/span><\/a><span style=\"font-weight: 400\">. \u00a0Here is an <\/span><a href=\"https:\/\/www.researchgate.net\/profile\/Josh_Mitteldorf\/publication\/43048830_Aging_is_not_a_process_of_wear_and_tear\/links\/00b4951dc4b03556a2000000.pdf\"><span style=\"font-weight: 400\">academic paper<\/span><\/a><span style=\"font-weight: 400\"> on the subject.<\/span><\/p>\n<p><b>\u201cIf the body could rejuvenate itself, it would already have done so.\u201d<\/b><\/p>\n<p><span style=\"font-weight: 400\">This is also a common view, and harder to dispel. \u00a0I think it is just as wrong as the one above, but full disclosure compells me to admit that I\u2019m still in a minority on this question.<\/span><\/p>\n<p><span style=\"font-weight: 400\">Since the 1960s, Nature has become an object of reverence, especially among the secular quarter in Western culture, people who are skeptical of religious dogmas. \u00a0The myth is that evolution has worked for millions of years to perfect the individual, and that human intervention is more likely than not to trip over the law of unintended consequences. \u00a0Biochemistry is not only highly optimized, it is also highly intricate and every biochemical plays multiple roles. \u00a0<\/span><\/p>\n<p><span style=\"font-weight: 400\">Like most myths, this one carries some truth. \u00a0A lot of Western medicine treats symptoms, not causes, and has questionable value in the long run. \u00a0Human attempts to \u201cmanage\u201d nature have been fraught with rude surprises. \u00a0And a natural diet of vegetables and fruits is a much better starting place for healthy nutrition than is a diet of processed food.<\/span><\/p>\n<p><span style=\"font-weight: 400\">But \u201cnatural medicine\u201d can never reverse aging. \u00a0The problem is that we are not just evolved to be strong and fertile individual competitors, but we are also evolved to be part of a stable ecosystem. \u00a0Aging was bequeathed to us by evolution, not for our sake as individuals, but as a way to stabilize ecosystems. \u00a0Individuals need to die on a schedule that is internally determined because if we left the matter of death to the world outside, then starvation would be the principal cause of death, and starvation tends to take everyone down at the same time. \u00a0This is called \u201cextinction\u201d. \u00a0The population can\u2019t afford to eat whatever is available and die only when the food runs out, because then everyone would die at once. \u00a0The population would swing wildly up and down. \u00a0Evolution has taken pains to protect our species from extinction, just as surely as she has taken pains to make us individually tough and resilient and fertile.<\/span><\/p>\n<p><span style=\"font-weight: 400\">When it comes to aging, we can\u2019t assume that \u201cwe tinker with evolution\u2019s product at our peril,\u00a0because evolution has already done her best to make us live as long as possible.\u201d \u00a0In fact, the body\u2019s repair mechanisms slow down as we get older (just as we need them most). \u00a0The immune system goes haywire, failing to attack pathogens but turning on the self (arthritis, diabetes). \u00a0Healthy nerve and muscle cells commit suicide (Loss of nerve cells is part of Alzheimer\u2019s Disease; loss of muscle is called <\/span><a href=\"http:\/\/www.webmd.com\/healthy-aging\/sarcopenia-with-aging\"><i><span style=\"font-weight: 400\">sarcropenia<\/span><\/i><\/a><span style=\"font-weight: 400\">, a universal wasting disease.) \u00a0<\/span><\/p>\n<p><span style=\"font-weight: 400\">As we get older, the balance of signals in our blood changes in some ways that are random and some that are predetermined. \u00a0All the predetermined changes are detrimental; signals in the blood raise the level of inflammation, which is the most significant root cause of all the diseases of old age.<\/span><\/p>\n<p><span style=\"font-weight: 400\">The idea that aging was programmed into us for the sake of the ecosystem isn\u2019t just an abstract theory; the theory was devised to explain the reality that the aging body both shuts down repair mechanisms and turns on active self-destruction, in a way that looks quite deliberate. \u00a0All the principal mechanisms of aging have been preserved over the vast stretch of evolutionary time.\u00a0<\/span><\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: center\"><b>Examples of the Rebuilding Approach<\/b><\/p>\n<p><span style=\"font-weight: 400\">Prosthetic limbs, artificial knees and hips are nothing new, but they do keep getting better. \u00a0Computer technology promises artificial limbs that can interface with existing nerves so that <a href=\"http:\/\/www.nytimes.com\/2015\/05\/21\/technology\/a-bionic-approach-to-prosthetics-controlled-by-thought.html?_r=0\" target=\"_blank\">amputees can learn to control them<\/a>. \u00a0When lenses in the eyes become clouded by cataracts, surgery to replace the lens with plastic have become routine. \u00a0Artificial eyes are now conceivable, and there are <\/span><a href=\"http:\/\/www.extremetech.com\/extreme\/149106-the-first-real-high-resolution-user-configurable-bionic-eye\"><span style=\"font-weight: 400\">crude working models<\/span><\/a><span style=\"font-weight: 400\">. \u00a0Mechanical hearts would be most useful, but the technology has been the subject of an intensive bioengineering program since 1969, while <\/span><a href=\"http:\/\/www.sciencedaily.com\/releases\/2014\/03\/140327100814.htm\"><span style=\"font-weight: 400\">mortality rates remain stubbornly high<\/span><\/a><span style=\"font-weight: 400\">.<\/span><\/p>\n<p><a href=\"http:\/\/www.nibib.nih.gov\/science-education\/science-topics\/tissue-engineering-and-regenerative-medicine\"><span style=\"font-weight: 400\">Tissue engineers<\/span><\/a><span style=\"font-weight: 400\"> are working on techniques to grow organs on scaffolds. \u00a0<\/span><a href=\"http:\/\/ki.se\/en\/research\/synthetic-trachea-save-the-lives-of-dying-patients\"><span style=\"font-weight: 400\">Tracheas<\/span><\/a><span style=\"font-weight: 400\"> and <\/span><a href=\"http:\/\/www.cityofhope.org\/blog\/bladder-cancer-artificial-bladder\"><span style=\"font-weight: 400\">bladders<\/span><\/a><span style=\"font-weight: 400\"> have already been implanted successfully in humans. \u00a0<\/span><\/p>\n<p><span style=\"font-weight: 400\">Despite impressive technological advances, the challenge facing this approach is formidable. \u00a0Things that go wrong as we age include clogged arteries, inelastic skin, and weak, degraded muscles. \u00a0These parts are not easily replaced. \u00a0Brain aging presents the ultimate challenge. \u00a0No one wants a prosthetic brain. \u00a0(<\/span><a href=\"http:\/\/singularityhub.com\/2015\/01\/25\/if-you-upload-your-mind-to-a-computer-are-you-still-you\/\"><span style=\"font-weight: 400\">Maybe I\u2019m wrong about this<\/span><\/a><span style=\"font-weight: 400\">.) <\/span><\/p>\n<p><span style=\"font-weight: 400\">Aubrey de Grey and his SENS Foundation have prominently championed the repair-and-replace approach to geriatric medicine. \u00a0The current research program of the SENS Foundation (from their <\/span><a href=\"http:\/\/sens.org\/research\"><span style=\"font-weight: 400\">web site<\/span><\/a><span style=\"font-weight: 400\">) includes <\/span><\/p>\n<ul>\n<ul>\n<ul>\n<li>Engineering new mitochondrial genes<\/li>\n<li>Fighting cancer by shutting down the cancer cell\u2019s ability to maintain telomeres<\/li>\n<li>Convincing the body\u2019s immune system to attack amyloid plaques<\/li>\n<li><span style=\"color: #0000ff\"><b>De-fanging or eliminating senescent cells<\/b><\/span><\/li>\n<li>Enhancing lipofuscin clearance<\/li>\n<li>Engineering a new thymus<\/li>\n<li><span style=\"color: #0000ff\"><b>Epimutations in single aging cells<\/b><\/span><\/li>\n<li>Finding amyloid in the heart<\/li>\n<li>Quantifying extracellular crosslinks<\/li>\n<li>Rejuvenating risk\/benefit analysis<\/li>\n<li><span style=\"color: #0000ff\"><b>Rejuvenating the microenvironment<\/b><\/span><\/li>\n<li><span style=\"color: #0000ff\"><b>Repopulating the Gut<\/b><\/span><\/li>\n<li>Scaling up glucosepane research<\/li>\n<\/ul>\n<\/ul>\n<\/ul>\n<p><b><span style=\"color: blue\">Four of the thirteen<\/span><\/b> may be regarded as signaling approaches; the rest are conceived as building understanding and a technology of control at the molecular level that SENS hopes will ultimately be the basis for engineering aging out of the human metabolism.<\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: center\"><b>Examples of the Signaling Approach<\/b><\/p>\n<p>&nbsp;<\/p>\n<p>A growing number of anti-aging researchers are betting on the idea that we don&#8217;t need to repair everything that goes wrong with aging because the body can repair itself, if only we can rejuvenate the signaling environment.<\/p>\n<p><b><b>FOXN1 rejuvenates the thymus<\/b><\/b><\/p>\n<p><span style=\"font-weight: 400\">The slow disappearance (\u201cinvolution\u201d) of the thymus over a lifetime has been implicated in the age-related decline of the immune system. \u00a0The rebuilding approach seeks to replace the aged thymus with tissue engineering [<\/span><a href=\"http:\/\/www.jimmunol.org\/content\/194\/10\/4784.short\"><span style=\"font-weight: 400\">ref<\/span><\/a><span style=\"font-weight: 400\">, <\/span><a href=\"http:\/\/www.nature.com\/nature\/journal\/v441\/n7096\/abs\/nature04850.html\"><span style=\"font-weight: 400\">ref<\/span><\/a><span style=\"font-weight: 400\">]; in contrast, the signaling approach seeks to stimulate the body to regrow the thymus on its own. \u00a0Of course, this is the easier approach, if it works. \u00a0Greg Fahy <\/span><a href=\"http:\/\/online.liebertpub.com\/doi\/abs\/10.1089\/109454503322733063\"><span style=\"font-weight: 400\">has reported success<\/span><\/a><span style=\"font-weight: 400\"> with growth hormone. \u00a0Several labs have recently reported hopeful signs that a signal protein called FOXN1 might be a specific trigger for regrowth of the thymus [<\/span><a href=\"http:\/\/www.jimmunol.org\/content\/194\/1_Supplement\/188.4.short\"><span style=\"font-weight: 400\">ref<\/span><\/a><span style=\"font-weight: 400\">, <\/span><a href=\"http:\/\/www.immunityageing.com\/content\/12\/1\/18\"><span style=\"font-weight: 400\">ref<\/span><\/a><span style=\"font-weight: 400\">].<\/span><\/p>\n<p>&nbsp;<\/p>\n<p><b><b>J147<\/b><\/b><\/p>\n<p><span style=\"font-weight: 400\">Last week, a <\/span><a href=\"http:\/\/www.salk.edu\/news-release\/experimental-drug-targeting-alzheimers-disease-shows-anti-aging-effects\/\"><span style=\"font-weight: 400\">press release<\/span><\/a><span style=\"font-weight: 400\"> from David Schubert\u2019s group in the Salk Laboratories in La Jolla made headlines for J147, a compound they have focused on more intently. \u00a0The world was introduced to J147 with a <\/span><a href=\"http:\/\/journals.plos.org\/plosone\/article?id=10.1371\/journal.pone.0027865\"><span style=\"font-weight: 400\">2011 article<\/span><\/a><span style=\"font-weight: 400\"> in the high-profile journal <em>PLOS One<\/em>, which didn\u2019t receive as much attention as it deserved. \u00a0There is a <\/span><a href=\"http:\/\/www.impactaging.com\/papers\/v7\/n11\/abs\/100838a.html\"><span style=\"font-weight: 400\">new article<\/span><\/a><span style=\"font-weight: 400\"> in the subsidy journal <strong><em>Aging<\/em><\/strong> that is getting more attention that it deserves.<\/span><\/p>\n<p><span style=\"font-weight: 400\">The most notable thing about J147 is that it is a promising result from a new methodology for drug development. \u00a0Schubert\u2019s lab began with curcumin, the active neuroprotective and anti-inflammatory component of turmeric. \u00a0Chemists synthesized and isolated hundreds of chemical cousins of curcumin, which were screened in cell cultures for neuroprotective activity at lower and lower doses. \u00a0<\/span><\/p>\n<p><span style=\"font-weight: 400\">In the end, the molecule J147 doesn\u2019t look much like curcumin.<\/span><\/p>\n<figure style=\"width: 302px\" class=\"wp-caption alignleft\"><img loading=\"lazy\" decoding=\"async\" class=\"\" src=\"http:\/\/patentimages.storage.googleapis.com\/US20100305181A1\/US20100305181A1-20101202-C00011.png\" alt=\"\" width=\"312\" height=\"142\" \/><figcaption class=\"wp-caption-text\">J147<\/figcaption><\/figure>\n<figure style=\"width: 230px\" class=\"wp-caption alignright\"><img loading=\"lazy\" decoding=\"async\" class=\"\" src=\"https:\/\/upload.wikimedia.org\/wikipedia\/commons\/thumb\/c\/c9\/CurcuminKeto.svg\/240px-CurcuminKeto.svg.png\" alt=\"\" width=\"240\" height=\"70\" \/><figcaption class=\"wp-caption-text\">Curcumin<\/figcaption><\/figure>\n<p><span style=\"font-weight: 400\">Both molecules have two aromatic rings. \u00a0The curcumin molecule is mirror symmetric, which J147 is not. \u00a0And J147 contains fluorine, which no natural biomolecules do. \u00a0(Among popular drugs Prozac and Lipitor contain fluorine.)<\/span><\/p>\n<p><span style=\"font-weight: 400\">The best ones were tested in rodents. \u00a0J147 improved memory in young mice and old. \u00a0In a mouse strain genetically engineered to be vulnerable something close to human Alzheimer\u2019s disease, daily doses of J147 were able to delay onset of memory loss. \u00a0Even after the mice suffered memory loss, J147 was able to reverse it [<\/span><a href=\"http:\/\/www.ncbi.nlm.nih.gov\/pmc\/articles\/PMC3706879\/\"><span style=\"font-weight: 400\">ref from 2013<\/span><\/a><span style=\"font-weight: 400\">]<\/span><\/p>\n<p><span style=\"font-weight: 400\">The reason the new paper made more of a splash than the old was that it was framed in terms of general anti-aging benefits, rather than neuroprotection or memory improvement. \u00a0The new paper reports that mice on a lifelong regimen of J147 show generalized abatement of markers of aging as they grow older. \u00a0The work is promising, but it was all done with SAMP8 mice, genetically engineered to contract a version of Alzheimer\u2019s disease, which usually kills them before they are a year old. \u00a0J147 has not yet been assayed for life extending potential in normal mice. \u00a0<\/span><\/p>\n<p><span style=\"font-weight: 400\">J147 is <\/span><a href=\"http:\/\/www.tocris.com\/dispprod.php?ItemId=399926#.VlI1d_mrSwU\" target=\"_blank\"><span style=\"font-weight: 400\">presently available<\/span><\/a><span style=\"font-weight: 400\"> in tiny quantities for a prodigious price.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p><b>ALK5 Inhibitors<\/b><\/p>\n<p><span style=\"font-weight: 400\">Mike and Irina Conboy working at UCBerkeley have identified ALK5 as a pro-aging signal, and report success in rejuvenating tissues and whole mice with a molecule engineered to block the ALK5 pathway. \u00a0Their <\/span><a href=\"http:\/\/www.ncbi.nlm.nih.gov\/pmc\/articles\/PMC4494916\/\"><span style=\"font-weight: 400\">recent paper<\/span><\/a><span style=\"font-weight: 400\"> may be viewed as a manifesto for the signaling approach to anti-aging medicine. \u00a0It begins:<\/span><\/p>\n<blockquote><p><span style=\"font-weight: 400\">Stem cell function declines with age largely due to the biochemical imbalances in their tissue niches, and this work demonstrates that aging imposes an elevation in transforming growth factor \u03b2 (TGF-\u03b2) signaling in the neurogenic niche of the hippocampus, analogous to the previously demonstrated changes in the myogenic niche of skeletal muscle with age. <\/span><\/p><\/blockquote>\n<p><span style=\"font-weight: 400\">This sentence is dense with meaning that is worth deconstructing.<\/span><\/p>\n<blockquote><p>Stem cell function declines with age largely due to the biochemical imbalances in their tissue niches,<\/p><\/blockquote>\n<p>The traditional view is that cells suffer damage with age. \u00a0Stem cells know they are old because of shorter telomeres. \u00a0They accumulate lipofuscin, and their DNA mutates over time. \u00a0Of course, aged stem cells cannot be as effective as young stem cells. \u00a0But the claim here is that the cells themselves are fine. \u00a0They are responding to signal molecules in the blood that tell them to lay down on the job.<\/p>\n<blockquote><p>elevation in transforming growth factor \u03b2 (TGF-\u03b2) signaling in the neurogenic niche of the hippocampus,<\/p><\/blockquote>\n<p>The bad actor is fingered and, what is more, its source is traced to the hippocampus\u2014a region of the brain known for neuroendocrine signaling, and <a href=\"http:\/\/onlinelibrary.wiley.com\/doi\/10.1002\/hipo.20637\/abstract\">implicated in other time-cyclic processes<\/a>.<\/p>\n<blockquote><p><span style=\"font-weight: 400\">analogous to the previously demonstrated changes in the myogenic niche of skeletal muscle with age. <\/span><\/p><\/blockquote>\n<p><span style=\"font-weight: 400\">The Conboys had previously found that <\/span><span style=\"font-weight: 400\">TGF-\u03b2 <\/span><span style=\"font-weight: 400\">signaling was responsible for inhibiting muscle growth in aged mice. <\/span><\/p>\n<p><span style=\"font-weight: 400\">The article goes on to describe the receptor for <\/span><span style=\"font-weight: 400\">TGF-\u03b2<\/span><span style=\"font-weight: 400\">, one step downstream, that is responsible for the negative consequences of <\/span><span style=\"font-weight: 400\">TGF-\u03b2 <\/span><span style=\"font-weight: 400\">signaling. \u00a0The receptor is called ALK5, and there are known molecules that can clog ALK5, blocking the signal pathway that has inhibited new growth in old bodies. \u201c<\/span><span style=\"font-weight: 400\">Very interestingly, both neurogenesis [new nerve cells] and myogenesis [new muscle tissue] were significantly enhanced in the aged mice treated with ALK5 inhibitor, compared to the animals receiving control buffer<\/span><span style=\"font-weight: 400\">.\u201d<\/span><\/p>\n<p>ALK5 inhibitors are also <a href=\"http:\/\/www.enzolifesciences.com\/ALX-270-445\/alk5-inhibitor-ii\/\" target=\"_blank\">available from lab supply houses<\/a>, even more dear than J147. \u00a0But, to be fair, the molecule is more difficult to synthesize and the dosage is probably smaller. \u00a0(In fact, we have only theory to guide us for human dosages, since both these molecules have yet to be tested in humans.)<\/p>\n<p>&nbsp;<\/p>\n<p><b>The Bottom Line<\/b><\/p>\n<p><span style=\"font-weight: 400\">In the beginning, anti-aging medicine was thought to be fanciful, if not impossible. \u00a0How could human engineering improve on processes that Nature has been perfecting for a billion years? \u00a0Then a science of regenerative medicine began\u00a0very slowly chipping away at that conventional wisdom, and a glimmer of hope pointed to promise of fixing the body directly with engineering, at least in the long run. \u00a0<\/span><\/p>\n<p><span style=\"font-weight: 400\">But a funny thing happened along the way. \u00a0There are indications in many areas that the body knows perfectly well how to rejuvenate itself, and we need only learn to speak the body\u2019s (biochemical) language in order to say, \u201cHave at it!\u201d \u00a0A few people like me are pointing out that this contradicts everything we thought we knew about evolutionary biology, and that the \u201cselfish gene\u201d is in need of an overhaul. \u00a0\u00a0But bench scientists are choosing to sidestep this theoretical debate and simply to do the practical thing. \u00a0They are pursuing a signaling approach because \u00a0it works.<\/span><\/p>\n<p>&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Aging is an accumulation of damage. \u00a0If we want to return the body to a more youthful state, we\u2019re going to have to repair that damage. The body never forgets how to be young. \u00a0Given the appropriate signaling environment, the body will restore itself to a youthful state. The future of medicine is the future &#8230; <a title=\"Anti-Aging Medicine: Two Paths Diverge\" class=\"read-more\" href=\"https:\/\/scienceblog.com\/joshmitteldorf\/2015\/11\/19\/anti-aging-medicine-two-paths-diverge\/\" aria-label=\"Read more about Anti-Aging Medicine: Two Paths Diverge\">Read more<\/a><\/p>\n","protected":false},"author":65,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[1],"tags":[],"class_list":["post-444","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"yoast_head":"<!-- This site is optimized with the Yoast SEO Premium plugin v27.4 (Yoast SEO v27.4) - https:\/\/yoast.com\/product\/yoast-seo-premium-wordpress\/ -->\n<title>Anti-Aging Medicine: Two Paths Diverge - Josh Mitteldorf<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/scienceblog.com\/joshmitteldorf\/2015\/11\/19\/anti-aging-medicine-two-paths-diverge\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Anti-Aging Medicine: Two Paths Diverge\" \/>\n<meta property=\"og:description\" content=\"Aging is an accumulation of damage. \u00a0If we want to return the body to a more youthful state, we\u2019re going to have to repair that damage. The body never forgets how to be young. \u00a0Given the appropriate signaling environment, the body will restore itself to a youthful state. The future of medicine is the future ... Read more\" \/>\n<meta property=\"og:url\" content=\"https:\/\/scienceblog.com\/joshmitteldorf\/2015\/11\/19\/anti-aging-medicine-two-paths-diverge\/\" \/>\n<meta property=\"og:site_name\" content=\"Josh Mitteldorf\" \/>\n<meta property=\"article:published_time\" content=\"2015-11-19T22:22:40+00:00\" \/>\n<meta property=\"article:modified_time\" content=\"2015-11-22T21:43:47+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/images.rapgenius.com\/3a78119a78c1de70b4374b9787862ef0.320x246x1.jpg\" \/>\n<meta name=\"author\" content=\"Josh Mitteldorf\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"Josh Mitteldorf\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"13 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\\\/\\\/scienceblog.com\\\/joshmitteldorf\\\/2015\\\/11\\\/19\\\/anti-aging-medicine-two-paths-diverge\\\/#article\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/scienceblog.com\\\/joshmitteldorf\\\/2015\\\/11\\\/19\\\/anti-aging-medicine-two-paths-diverge\\\/\"},\"author\":{\"name\":\"Josh Mitteldorf\",\"@id\":\"https:\\\/\\\/scienceblog.com\\\/joshmitteldorf\\\/#\\\/schema\\\/person\\\/214c5d1dad9f15c48f03128d5cfccdb1\"},\"headline\":\"Anti-Aging Medicine: Two Paths Diverge\",\"datePublished\":\"2015-11-19T22:22:40+00:00\",\"dateModified\":\"2015-11-22T21:43:47+00:00\",\"mainEntityOfPage\":{\"@id\":\"https:\\\/\\\/scienceblog.com\\\/joshmitteldorf\\\/2015\\\/11\\\/19\\\/anti-aging-medicine-two-paths-diverge\\\/\"},\"wordCount\":2630,\"commentCount\":34,\"publisher\":{\"@id\":\"https:\\\/\\\/scienceblog.com\\\/joshmitteldorf\\\/#organization\"},\"image\":{\"@id\":\"https:\\\/\\\/scienceblog.com\\\/joshmitteldorf\\\/2015\\\/11\\\/19\\\/anti-aging-medicine-two-paths-diverge\\\/#primaryimage\"},\"thumbnailUrl\":\"https:\\\/\\\/images.rapgenius.com\\\/3a78119a78c1de70b4374b9787862ef0.320x246x1.jpg\",\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"CommentAction\",\"name\":\"Comment\",\"target\":[\"https:\\\/\\\/scienceblog.com\\\/joshmitteldorf\\\/2015\\\/11\\\/19\\\/anti-aging-medicine-two-paths-diverge\\\/#respond\"]}],\"copyrightYear\":\"2015\",\"copyrightHolder\":{\"@id\":\"https:\\\/\\\/scienceblog.com\\\/#organization\"}},{\"@type\":\"WebPage\",\"@id\":\"https:\\\/\\\/scienceblog.com\\\/joshmitteldorf\\\/2015\\\/11\\\/19\\\/anti-aging-medicine-two-paths-diverge\\\/\",\"url\":\"https:\\\/\\\/scienceblog.com\\\/joshmitteldorf\\\/2015\\\/11\\\/19\\\/anti-aging-medicine-two-paths-diverge\\\/\",\"name\":\"Anti-Aging Medicine: Two Paths Diverge - Josh Mitteldorf\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/scienceblog.com\\\/joshmitteldorf\\\/#website\"},\"primaryImageOfPage\":{\"@id\":\"https:\\\/\\\/scienceblog.com\\\/joshmitteldorf\\\/2015\\\/11\\\/19\\\/anti-aging-medicine-two-paths-diverge\\\/#primaryimage\"},\"image\":{\"@id\":\"https:\\\/\\\/scienceblog.com\\\/joshmitteldorf\\\/2015\\\/11\\\/19\\\/anti-aging-medicine-two-paths-diverge\\\/#primaryimage\"},\"thumbnailUrl\":\"https:\\\/\\\/images.rapgenius.com\\\/3a78119a78c1de70b4374b9787862ef0.320x246x1.jpg\",\"datePublished\":\"2015-11-19T22:22:40+00:00\",\"dateModified\":\"2015-11-22T21:43:47+00:00\",\"breadcrumb\":{\"@id\":\"https:\\\/\\\/scienceblog.com\\\/joshmitteldorf\\\/2015\\\/11\\\/19\\\/anti-aging-medicine-two-paths-diverge\\\/#breadcrumb\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\\\/\\\/scienceblog.com\\\/joshmitteldorf\\\/2015\\\/11\\\/19\\\/anti-aging-medicine-two-paths-diverge\\\/\"]}]},{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\\\/\\\/scienceblog.com\\\/joshmitteldorf\\\/2015\\\/11\\\/19\\\/anti-aging-medicine-two-paths-diverge\\\/#primaryimage\",\"url\":\"https:\\\/\\\/images.rapgenius.com\\\/3a78119a78c1de70b4374b9787862ef0.320x246x1.jpg\",\"contentUrl\":\"https:\\\/\\\/images.rapgenius.com\\\/3a78119a78c1de70b4374b9787862ef0.320x246x1.jpg\"},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\\\/\\\/scienceblog.com\\\/joshmitteldorf\\\/2015\\\/11\\\/19\\\/anti-aging-medicine-two-paths-diverge\\\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\\\/\\\/scienceblog.com\\\/joshmitteldorf\\\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Anti-Aging Medicine: Two Paths Diverge\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\\\/\\\/scienceblog.com\\\/joshmitteldorf\\\/#website\",\"url\":\"https:\\\/\\\/scienceblog.com\\\/joshmitteldorf\\\/\",\"name\":\"Josh Mitteldorf\",\"description\":\"Aging Matters\",\"publisher\":{\"@id\":\"https:\\\/\\\/scienceblog.com\\\/joshmitteldorf\\\/#organization\"},\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\\\/\\\/scienceblog.com\\\/joshmitteldorf\\\/?s={search_term_string}\"},\"query-input\":{\"@type\":\"PropertyValueSpecification\",\"valueRequired\":true,\"valueName\":\"search_term_string\"}}],\"inLanguage\":\"en-US\"},{\"@type\":\"Organization\",\"@id\":\"https:\\\/\\\/scienceblog.com\\\/joshmitteldorf\\\/#organization\",\"name\":\"Josh Mitteldorf\",\"url\":\"https:\\\/\\\/scienceblog.com\\\/joshmitteldorf\\\/\",\"logo\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\\\/\\\/scienceblog.com\\\/joshmitteldorf\\\/#\\\/schema\\\/logo\\\/image\\\/\",\"url\":\"https:\\\/\\\/scienceblog.com\\\/joshmitteldorf\\\/wp-content\\\/uploads\\\/sites\\\/2\\\/2024\\\/09\\\/1058476001.jpg\",\"contentUrl\":\"https:\\\/\\\/scienceblog.com\\\/joshmitteldorf\\\/wp-content\\\/uploads\\\/sites\\\/2\\\/2024\\\/09\\\/1058476001.jpg\",\"width\":864,\"height\":363,\"caption\":\"Josh Mitteldorf\"},\"image\":{\"@id\":\"https:\\\/\\\/scienceblog.com\\\/joshmitteldorf\\\/#\\\/schema\\\/logo\\\/image\\\/\"}},{\"@type\":\"Person\",\"@id\":\"https:\\\/\\\/scienceblog.com\\\/joshmitteldorf\\\/#\\\/schema\\\/person\\\/214c5d1dad9f15c48f03128d5cfccdb1\",\"name\":\"Josh Mitteldorf\",\"image\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/d3a8498f3d727156673030716d233edc57840f110d501b1b523e1780e9043b92?s=96&d=mm&r=g\",\"url\":\"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/d3a8498f3d727156673030716d233edc57840f110d501b1b523e1780e9043b92?s=96&d=mm&r=g\",\"contentUrl\":\"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/d3a8498f3d727156673030716d233edc57840f110d501b1b523e1780e9043b92?s=96&d=mm&r=g\",\"caption\":\"Josh Mitteldorf\"},\"description\":\"Josh Mitteldorf studies evolutionary theory of aging using computer simulations. The surprising fact that our bodies are genetically programmed to age and to die offers an enormous opportunity for medical intervention. It may be that therapies to slow the progress of aging need not repair or regenerate anything, but only need to interfere with an existing program of self-destruction. Mitteldorf has taught a weekly yoga class for thirty years. He is an advocate for vigorous self care, including exercise, meditation and caloric restriction. After earning a PhD in astrophysicist, Mitteldorf moved to evolutionary biology as a primary field in 1996. He has taught at Harvard, Berkeley, Bryn Mawr, LaSalle and Temple University. He is presently affiliated with MIT as a visiting scholar. In private life, Mitteldorf is an advocate for election integrity as well as public health. He is an avid amateur musician, playing piano in chamber groups, French horn in community orchestras. His two daughters are among the first children adopted from China in the mid-1980s. Much to the surprise of evolutionary biologists, genetic experiments indicate that aging has been selected as an adaptation for its own sake. This poses a conundrum: the impact of aging on individual fitness is wholly negative, so aging must be regarded as a kind of evolutionary altruism. Unlike other forms of evolutionary altruism, aging offers benefits to the community that are weak, and not well focussed on near kin of the altruist. This makes the mechanism challenging to understand and to model. more at http:\\\/\\\/mathforum.org\\\/~josh\",\"sameAs\":[\"http:\\\/\\\/AgingAdvice.org\"],\"url\":\"https:\\\/\\\/scienceblog.com\\\/joshmitteldorf\\\/author\\\/joshmitteldorf\\\/\"}]}<\/script>\n<!-- \/ Yoast SEO Premium plugin. -->","yoast_head_json":{"title":"Anti-Aging Medicine: Two Paths Diverge - Josh Mitteldorf","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/scienceblog.com\/joshmitteldorf\/2015\/11\/19\/anti-aging-medicine-two-paths-diverge\/","og_locale":"en_US","og_type":"article","og_title":"Anti-Aging Medicine: Two Paths Diverge","og_description":"Aging is an accumulation of damage. \u00a0If we want to return the body to a more youthful state, we\u2019re going to have to repair that damage. The body never forgets how to be young. \u00a0Given the appropriate signaling environment, the body will restore itself to a youthful state. The future of medicine is the future ... Read more","og_url":"https:\/\/scienceblog.com\/joshmitteldorf\/2015\/11\/19\/anti-aging-medicine-two-paths-diverge\/","og_site_name":"Josh Mitteldorf","article_published_time":"2015-11-19T22:22:40+00:00","article_modified_time":"2015-11-22T21:43:47+00:00","og_image":[{"url":"https:\/\/images.rapgenius.com\/3a78119a78c1de70b4374b9787862ef0.320x246x1.jpg","type":"","width":"","height":""}],"author":"Josh Mitteldorf","twitter_card":"summary_large_image","twitter_misc":{"Written by":"Josh Mitteldorf","Est. reading time":"13 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"Article","@id":"https:\/\/scienceblog.com\/joshmitteldorf\/2015\/11\/19\/anti-aging-medicine-two-paths-diverge\/#article","isPartOf":{"@id":"https:\/\/scienceblog.com\/joshmitteldorf\/2015\/11\/19\/anti-aging-medicine-two-paths-diverge\/"},"author":{"name":"Josh Mitteldorf","@id":"https:\/\/scienceblog.com\/joshmitteldorf\/#\/schema\/person\/214c5d1dad9f15c48f03128d5cfccdb1"},"headline":"Anti-Aging Medicine: Two Paths Diverge","datePublished":"2015-11-19T22:22:40+00:00","dateModified":"2015-11-22T21:43:47+00:00","mainEntityOfPage":{"@id":"https:\/\/scienceblog.com\/joshmitteldorf\/2015\/11\/19\/anti-aging-medicine-two-paths-diverge\/"},"wordCount":2630,"commentCount":34,"publisher":{"@id":"https:\/\/scienceblog.com\/joshmitteldorf\/#organization"},"image":{"@id":"https:\/\/scienceblog.com\/joshmitteldorf\/2015\/11\/19\/anti-aging-medicine-two-paths-diverge\/#primaryimage"},"thumbnailUrl":"https:\/\/images.rapgenius.com\/3a78119a78c1de70b4374b9787862ef0.320x246x1.jpg","inLanguage":"en-US","potentialAction":[{"@type":"CommentAction","name":"Comment","target":["https:\/\/scienceblog.com\/joshmitteldorf\/2015\/11\/19\/anti-aging-medicine-two-paths-diverge\/#respond"]}],"copyrightYear":"2015","copyrightHolder":{"@id":"https:\/\/scienceblog.com\/#organization"}},{"@type":"WebPage","@id":"https:\/\/scienceblog.com\/joshmitteldorf\/2015\/11\/19\/anti-aging-medicine-two-paths-diverge\/","url":"https:\/\/scienceblog.com\/joshmitteldorf\/2015\/11\/19\/anti-aging-medicine-two-paths-diverge\/","name":"Anti-Aging Medicine: Two Paths Diverge - Josh Mitteldorf","isPartOf":{"@id":"https:\/\/scienceblog.com\/joshmitteldorf\/#website"},"primaryImageOfPage":{"@id":"https:\/\/scienceblog.com\/joshmitteldorf\/2015\/11\/19\/anti-aging-medicine-two-paths-diverge\/#primaryimage"},"image":{"@id":"https:\/\/scienceblog.com\/joshmitteldorf\/2015\/11\/19\/anti-aging-medicine-two-paths-diverge\/#primaryimage"},"thumbnailUrl":"https:\/\/images.rapgenius.com\/3a78119a78c1de70b4374b9787862ef0.320x246x1.jpg","datePublished":"2015-11-19T22:22:40+00:00","dateModified":"2015-11-22T21:43:47+00:00","breadcrumb":{"@id":"https:\/\/scienceblog.com\/joshmitteldorf\/2015\/11\/19\/anti-aging-medicine-two-paths-diverge\/#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/scienceblog.com\/joshmitteldorf\/2015\/11\/19\/anti-aging-medicine-two-paths-diverge\/"]}]},{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/scienceblog.com\/joshmitteldorf\/2015\/11\/19\/anti-aging-medicine-two-paths-diverge\/#primaryimage","url":"https:\/\/images.rapgenius.com\/3a78119a78c1de70b4374b9787862ef0.320x246x1.jpg","contentUrl":"https:\/\/images.rapgenius.com\/3a78119a78c1de70b4374b9787862ef0.320x246x1.jpg"},{"@type":"BreadcrumbList","@id":"https:\/\/scienceblog.com\/joshmitteldorf\/2015\/11\/19\/anti-aging-medicine-two-paths-diverge\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/scienceblog.com\/joshmitteldorf\/"},{"@type":"ListItem","position":2,"name":"Anti-Aging Medicine: Two Paths Diverge"}]},{"@type":"WebSite","@id":"https:\/\/scienceblog.com\/joshmitteldorf\/#website","url":"https:\/\/scienceblog.com\/joshmitteldorf\/","name":"Josh Mitteldorf","description":"Aging Matters","publisher":{"@id":"https:\/\/scienceblog.com\/joshmitteldorf\/#organization"},"potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/scienceblog.com\/joshmitteldorf\/?s={search_term_string}"},"query-input":{"@type":"PropertyValueSpecification","valueRequired":true,"valueName":"search_term_string"}}],"inLanguage":"en-US"},{"@type":"Organization","@id":"https:\/\/scienceblog.com\/joshmitteldorf\/#organization","name":"Josh Mitteldorf","url":"https:\/\/scienceblog.com\/joshmitteldorf\/","logo":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/scienceblog.com\/joshmitteldorf\/#\/schema\/logo\/image\/","url":"https:\/\/scienceblog.com\/joshmitteldorf\/wp-content\/uploads\/sites\/2\/2024\/09\/1058476001.jpg","contentUrl":"https:\/\/scienceblog.com\/joshmitteldorf\/wp-content\/uploads\/sites\/2\/2024\/09\/1058476001.jpg","width":864,"height":363,"caption":"Josh Mitteldorf"},"image":{"@id":"https:\/\/scienceblog.com\/joshmitteldorf\/#\/schema\/logo\/image\/"}},{"@type":"Person","@id":"https:\/\/scienceblog.com\/joshmitteldorf\/#\/schema\/person\/214c5d1dad9f15c48f03128d5cfccdb1","name":"Josh Mitteldorf","image":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/secure.gravatar.com\/avatar\/d3a8498f3d727156673030716d233edc57840f110d501b1b523e1780e9043b92?s=96&d=mm&r=g","url":"https:\/\/secure.gravatar.com\/avatar\/d3a8498f3d727156673030716d233edc57840f110d501b1b523e1780e9043b92?s=96&d=mm&r=g","contentUrl":"https:\/\/secure.gravatar.com\/avatar\/d3a8498f3d727156673030716d233edc57840f110d501b1b523e1780e9043b92?s=96&d=mm&r=g","caption":"Josh Mitteldorf"},"description":"Josh Mitteldorf studies evolutionary theory of aging using computer simulations. The surprising fact that our bodies are genetically programmed to age and to die offers an enormous opportunity for medical intervention. It may be that therapies to slow the progress of aging need not repair or regenerate anything, but only need to interfere with an existing program of self-destruction. Mitteldorf has taught a weekly yoga class for thirty years. He is an advocate for vigorous self care, including exercise, meditation and caloric restriction. After earning a PhD in astrophysicist, Mitteldorf moved to evolutionary biology as a primary field in 1996. He has taught at Harvard, Berkeley, Bryn Mawr, LaSalle and Temple University. He is presently affiliated with MIT as a visiting scholar. In private life, Mitteldorf is an advocate for election integrity as well as public health. He is an avid amateur musician, playing piano in chamber groups, French horn in community orchestras. His two daughters are among the first children adopted from China in the mid-1980s. Much to the surprise of evolutionary biologists, genetic experiments indicate that aging has been selected as an adaptation for its own sake. This poses a conundrum: the impact of aging on individual fitness is wholly negative, so aging must be regarded as a kind of evolutionary altruism. Unlike other forms of evolutionary altruism, aging offers benefits to the community that are weak, and not well focussed on near kin of the altruist. This makes the mechanism challenging to understand and to model. more at http:\/\/mathforum.org\/~josh","sameAs":["http:\/\/AgingAdvice.org"],"url":"https:\/\/scienceblog.com\/joshmitteldorf\/author\/joshmitteldorf\/"}]}},"jetpack_featured_media_url":"","jetpack_shortlink":"https:\/\/wp.me\/pgtN8h-7a","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/scienceblog.com\/joshmitteldorf\/wp-json\/wp\/v2\/posts\/444","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/scienceblog.com\/joshmitteldorf\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/scienceblog.com\/joshmitteldorf\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/scienceblog.com\/joshmitteldorf\/wp-json\/wp\/v2\/users\/65"}],"replies":[{"embeddable":true,"href":"https:\/\/scienceblog.com\/joshmitteldorf\/wp-json\/wp\/v2\/comments?post=444"}],"version-history":[{"count":0,"href":"https:\/\/scienceblog.com\/joshmitteldorf\/wp-json\/wp\/v2\/posts\/444\/revisions"}],"wp:attachment":[{"href":"https:\/\/scienceblog.com\/joshmitteldorf\/wp-json\/wp\/v2\/media?parent=444"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/scienceblog.com\/joshmitteldorf\/wp-json\/wp\/v2\/categories?post=444"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/scienceblog.com\/joshmitteldorf\/wp-json\/wp\/v2\/tags?post=444"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}