Performance-enhancing substances ( PESs ), also known as performance-enhancing drugs ( PEDs ), are substances that are used to improve any form of activity performance in humans.
98-753: Chemical Neurological Life extension is the concept of extending the human lifespan , either modestly through improvements in medicine or dramatically by increasing the maximum lifespan beyond its generally-settled biological limit of around 125 years . Several researchers in the area, along with "life extensionists", " immortalists ", or " longevists " (those who wish to achieve longer lives themselves), postulate that future breakthroughs in tissue rejuvenation , stem cells , regenerative medicine , molecular repair, gene therapy , pharmaceuticals, and organ replacement (such as with artificial organs or xenotransplantations ) will eventually enable humans to have indefinite lifespans through complete rejuvenation to
196-428: A fluid-filled body cavity , and the space between their organ systems is filled with parenchyma . Planarians lack a circulatory system, and absorb oxygen through their body wall. They uptake food to their gut using a muscular pharynx, and nutrients diffuse to internal tissues. A three-branched intestine runs across almost the entire body, and includes a single anterior and two posterior branches. The planarian intestine
294-539: A pulmonary embolism or stroke. Per the WADA, it is a banned substance. Urine samples can be tested via electrophoresis , and blood samples via indirect markers. Gene doping agents are a relatively recently described class of athletic performance-enhancing substances. These drug therapies, which involve viral vector -mediated gene transfer , are not known to currently be in use as of 2020 . Also known as anabolic steroid precursors, they promote lean body mass . Once in
392-686: A CR diet, which are known as caloric restriction mimetic drugs, such as rapamycin and metformin . Sirtuin activating polyphenols , such as resveratrol and pterostilbene , and flavonoids , such as quercetin and fisetin , as well as oleic acid are dietary supplements that have also been studied in this context. Other common supplements with less clear biological pathways to target aging include lipoic acid , senolytics , and coenzyme Q10 . While agents such as these have some limited laboratory evidence of efficacy in animals, there are no studies to date in humans for drugs that may promote life extension, mainly because research investment remains at
490-431: A bilobed shaped cerebral ganglion that is referred to as the planarian brain . Longitudinal ventral nerve chords extend from the brain to the tail. Transverse nerves, commissure , connect the ventral nerve chords forming ladder-like nerve system. The brain has been shown to exhibit spontaneous electrophysiological oscillations, similar to the electroencephalographic ( EEG ) activity of other animals. The planarian has
588-517: A collection of quite predictable diseases caused by the deterioration of the body." The two main arguments used are that aging is both inevitable and universal while diseases are not. However, not everyone agrees. Harry R. Moody, director of academic affairs for AARP , notes that what is normal and what is disease strongly depend on a historical context. David Gems , assistant director of the Institute of Healthy Ageing, argues that aging should be viewed as
686-572: A desire among athletes to use testosterone. In 1967, the first prohibited substance list and anti-doping measures were implemented at the 1968 Olympics. In the 1980s, the main PEDs were cortisone and anabolic steroids . In 1988, the United States Congress established the Anti-Drug Abuse Act to criminalize the distribution and possession of non-medical anabolic steroids. In 1999, WADA
784-679: A desire of humanity and a mainstay motif in the history of scientific pursuits and ideas throughout history, from the Sumerian Epic of Gilgamesh and the Egyptian Smith medical papyrus , all the way through the Taoists , Ayurveda practitioners, alchemists , hygienists such as Luigi Cornaro , Johann Cohausen and Christoph Wilhelm Hufeland , and philosophers such as Francis Bacon , René Descartes , Benjamin Franklin and Nicolas Condorcet . However,
882-726: A diet consisting of dried figs which was thought, at the time, to be a significant factor in winning the 200-yard stade race. Ancient Greek athletes at the time also incorporated substances such as wine and brandy into their training routines. Stimulants derived from plants (e.g., Cola nitida , Bufotein , etc.) were used by the Roman gladiators to overcome injuries and fatigue. In the late 19th century as modern medicine and pharmacology were developing, PEDs saw an increase in use. Supplements were now exclusively being used to enhance muscular work capacity. The main substances being used included alcoholic drinks , caffeine, and mixtures created by
980-607: A discipline. Planarians are also an emerging model organism for aging research . These animals have an apparently limitless regenerative capacity, and asexual Schmidtea mediterranea has been shown to maintain its telomere length through regeneration. Planarian regeneration combines new tissue production with reorganization to the existing anatomy, morphallaxis. The rate of tissue regrowth varies between species, but in frequently used lab species, functional regenerated tissues are available already 7–10 days following tissue amputation. Regeneration starts following an injury that require
1078-537: A disease. In response to the universality of aging, David Gems notes that it is as misleading as arguing that Basenji are not dogs because they do not bark. Because of the universality of aging he calls it a "special sort of disease". Robert M. Perlman, coined the terms "aging syndrome" and "disease complex" in 1954 to describe aging. The discussion whether aging should be viewed as a disease or not has important implications. One view is, this would stimulate pharmaceutical companies to develop life extension therapies and in
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#17328838127871176-691: A feared-self. Though many scientists state that life extension and radical life extension are possible, there are still no international or national programs focused on radical life extension. There are political forces working both for and against life extension. By 2012, in Russia, the United States, Israel, and the Netherlands, the Longevity political parties started. They aimed to provide political support to radical life extension research and technologies, and ensure
1274-493: A healthy youthful condition (agerasia). The ethical ramifications, if life extension becomes a possibility, are debated by bioethicists . The sale of purported anti-aging products such as supplements and hormone replacement is a lucrative global industry. For example, the industry that promotes the use of hormones as a treatment for consumers to slow or reverse the aging process in the US market generated about $ 50 billion of revenue
1372-459: A hoped-for self (e.g., keeping a youthful skin) or to avoid a feared-self (e.g., looking old). The research shows that when consumers pursue a hoped-for self, it is expectations of success that most strongly drive their motivation to use the product. The research also shows why doing badly when trying to avoid a feared self is more motivating than doing well. When product use is seen to fail it is more motivating than success when consumers seek to avoid
1470-483: A large sub-population of dormant or slow-cycling cells. The life history of planarians make them a model system for investigating a number of biological processes, many of which may have implications for human health and disease. Advances in molecular genetic technologies has made the study of gene function possible in these animals and scientists are studying them worldwide. Like other invertebrate model organisms, for example C. elegans and D. melanogaster ,
1568-412: A linear response rarely seen in biology." There are numerous chemicals intended to slow the aging process under study in animal models . One type of research is related to the observed effects of a calorie restriction (CR) diet, which has been shown to extend lifespan in some animals. Based on that research, there have been attempts to develop drugs that will have the same effect on the aging process as
1666-413: A longer period of decrepitude, and that the elderly in our current society are unhealthy. Religious people are no more likely to oppose life extension than the unaffiliated, though some variation exists between religious denominations. Most mainstream medical organizations and practitioners do not consider aging to be a disease. Biologist David Sinclair says: "I don't see aging as a disease, but as
1764-546: A low level, and regulatory standards are high. Aging is not recognized as a preventable condition by governments, indicating there is no clear pathway to approval of anti-aging medications. Further, anti-aging drug candidates are under constant review by regulatory authorities like the US Food and Drug Administration , which stated in 2023 that "no medication has been proven to slow or reverse the aging process." Future advances in nanomedicine could give rise to life extension through
1862-487: A novel aging route with substantially extended lifespan. In The Selfish Gene , Richard Dawkins describes an approach to life-extension that involves "fooling genes" into thinking the body is young. Dawkins attributes inspiration for this idea to Peter Medawar . The basic idea is that our bodies are composed of genes that activate throughout our lifetimes, some when we are young and others when we are older. Presumably, these genes are activated by environmental factors, and
1960-644: A particularly high risk, with those involved in gridiron football, basketball, wrestling, baseball, and gymnastics at the top. In sports, the term performance-enhancing drugs is popularly used in reference to anabolic steroids or their precursors (hence the colloquial term steroids ); anti-doping organizations apply the term broadly. Agencies such as the WADA and United States Anti-Doping Agency try to prevent athletes from using these drugs by performing drug tests. When medical exemptions are granted they are called therapeutic use exemptions . Planarian Planarians (triclads) are free-living flatworms of
2058-580: A popular model in research of regeneration and stem cell biology. The genome sequences of several species are available, as are tools for molecular biology analysis. The order Tricladida is split into three suborders, according to their phylogenetic relationships: Maricola , Cavernicola and Continenticola . Formerly, the Tricladida was split according to their habitat: Maricola (marine planarians); Paludicola (freshwater planarian); and Terricola (land planarians). Planarians move by beating cilia on
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#17328838127872156-498: A population is lowered by infant and child mortality , which are frequently linked to infectious diseases or nutrition problems. Later in life, vulnerability to accidents and age-related chronic disease such as cancer or cardiovascular disease play an increasing role in mortality. Extension of life expectancy and lifespan can often be achieved by access to improved medical care, vaccinations , good diet , exercise , and avoidance of hazards such as smoking . Maximum lifespan
2254-524: A privileged few. In an extended metaphor entitled " The Fable of the Dragon-Tyrant ", Bostrom envisions death as a monstrous dragon who demands human sacrifices. In the fable, after a lengthy debate between those who believe the dragon is a fact of life and those who believe the dragon can and should be destroyed, the dragon is finally killed. Bostrom argues that political inaction allowed many preventable human deaths to occur. Controversy about life extension
2352-512: A problem that desperately needs to be solved; and recording artist Steve Aoki , who has been called "one of the most prolific campaigners for life extension". In 1991, the American Academy of Anti-Aging Medicine (A4M) was formed. The American Board of Medical Specialties recognizes neither anti-aging medicine nor the A4M's professional standing. In 2003, Aubrey de Grey and David Gobel formed
2450-482: A promising candidate for further research within the field. Their study suggests that high levels of iron in the blood likely reduce, and genes involved in metabolising iron likely increase healthy years of life in humans. The same month other scientists report that yeast cells of the same genetic material and within the same environment age in two distinct ways, describe a biomolecular mechanism that can determine which process dominates during aging and genetically engineer
2548-522: A soft, flat, wedge-shaped body that may be black, brown, blue, gray, or white. The blunt, triangular head has two ocelli (eyespots), pigmented areas that are sensitive to light. There are two auricles (earlike projections) at the base of the head, which are sensitive to touch and the presence of certain chemicals. The mouth is located in the middle of the underside of the body, which is covered with hairlike projections (cilia). There are no circulatory or respiratory systems; oxygen enters and carbon dioxide leaves
2646-429: A variety of contexts. Use of stem cells taken from the umbilical cord or parts of the adult body may not provoke controversy. The controversies over cloning are similar, except general public opinion in most countries stands in opposition to reproductive cloning . Some proponents of therapeutic cloning predict the production of whole bodies, lacking consciousness, for eventual brain transplantation. Some critics dispute
2744-489: A viable treatment for bladder disease. Proponents of body part replacement and cloning contend that the required biotechnologies are likely to appear earlier than other life-extension technologies. The use of human stem cells , particularly embryonic stem cells , is controversial. Opponents' objections generally are based on interpretations of religious teachings or ethical considerations. Proponents of stem cell research point out that cells are routinely formed and destroyed in
2842-583: A year in 2009. The use of such hormone products has not been proven to be effective or safe. During the process of aging , an organism accumulates damage to its macromolecules , cells , tissues , and organs . Specifically, aging is characterized as and thought to be caused by "genomic instability, telomere attrition, epigenetic alterations, loss of proteostasis , deregulated nutrient sensing, mitochondrial dysfunction, cellular senescence , stem cell exhaustion, and altered intercellular communication." Oxidation damage to cellular contents caused by free radicals
2940-400: Is a blind sac , having no exit cavity, and therefore planarians uptake food and egest waste through the same orifice, located near the middle of the ventral body surface. The excretory system is made of many tubes with many flame cells and excretory pores on them. Also, flame cells remove unwanted liquids from the body by passing them through ducts which lead to excretory pores, where waste
3038-516: Is being conducted in university laboratories, and includes universities such as Harvard and UCLA . University researchers have made a number of breakthroughs in extending the lives of mice and insects by reversing certain aspects of aging. Theoretically, extension of maximum lifespan in humans could be achieved by reducing the rate of aging damage by periodic replacement of damaged tissues , molecular repair or rejuvenation of deteriorated cells and tissues, reversal of harmful epigenetic changes, or
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3136-613: Is believed to contribute to aging as well. The longest documented human lifespan is 122 years 164 days, the case of Jeanne Calment , who according to records was born in 1875 and died in 1997, whereas the maximum lifespan of a wildtype mouse, commonly used as a model in research on aging, is about three years. Genetic differences between humans and mice that may account for these different aging rates include differences in efficiency of DNA repair , antioxidant defenses, energy metabolism , proteostasis maintenance, and recycling mechanisms such as autophagy . The average life expectancy in
3234-456: Is cut from, can regenerate back into a complete organism over the course of a few weeks. New tissues can grow due to pluripotent stem cells that have the ability to create all the various cell types. These adult stem cells are called neoblasts , and comprise 20% or more of the cells in the adult animal. They are the only proliferating cells in the worm, and they differentiate into progeny that replace older cells. In addition, existing tissue
3332-634: Is determined by the rate of aging for a species inherent in its genes and by environmental factors. Widely recognized methods of extending maximum lifespan in model organisms such as nematodes , fruit flies, and mice include caloric restriction , gene manipulation , and administration of pharmaceuticals. Another technique uses evolutionary pressures such as breeding from only older members or altering levels of extrinsic mortality. Some animals such as hydra , planarian flatworms , and certain sponges , corals , and jellyfish do not die of old age and exhibit potential immortality. The extension of life has been
3430-405: Is due to fear of overpopulation and possible effects on society. Biogerontologist Aubrey De Grey counters the overpopulation critique by pointing out that the therapy could postpone or eliminate menopause , allowing women to space out their pregnancies over more years and thus decreasing the yearly population growth rate. Moreover, the philosopher and futurist Max More argues that, given that
3528-656: Is not only a childish desire to eat one's life and keep it; it is also an expression of a childish and narcissistic wish incompatible with devotion to posterity." John Harris, former editor-in-chief of the Journal of Medical Ethics, argues that as long as life is worth living, according to the person himself, we have a powerful moral imperative to save the life and thus to develop and offer life extension therapies to those who want them. Transhumanist philosopher Nick Bostrom has argued that any technological advances in life extension must be equitably distributed and not restricted to
3626-495: Is released on the dorsal surface of the planarian. The triclads have an anterior end or head where sense organs, such as eyes and chemoreceptors , are usually found. Some species have auricles that protrude from the margins of the head. The auricles can contain chemical and mechanical sensory receptors. The number of eyes in the triclads is variable depending on the species. While many species have two eyes (e.g. Dugesia or Microplana ), others have many more distributed along
3724-486: Is remodeled to restore symmetry and proportion of the new planaria that forms from a piece of a cut up organism. The organism itself does not have to be completely cut into separate pieces for the regeneration phenomenon to be witnessed. In fact, if the head of a planarian is cut in half down its center, and each side retained on the organism, it is possible for the planarian to regenerate two heads and continue to live. Researchers, including those from Tufts University in
3822-408: Is risky at best, and it cannot be assumed that interventions will result in comparable life extension factors. Longevity gains from dietary restriction, or from mutations studied previously, yield smaller benefits to Drosophila than to nematodes, and smaller still to mammals. This is not unexpected, since mammals have evolved to live many times the worm's lifespan, and humans live nearly twice as long as
3920-448: Is to discover or develop agents to delay, prevent, alleviate, or reverse age-related diseases. Removal of senescent cells with senolytics has been proposed as a method of enhancing immunity during aging. Senolytics eliminate senescent cells whereas senomorphics – with candidates such as Apigenin , Everolimus and Rapamycin – modulate properties of senescent cells without eliminating them, suppressing phenotypes of senescence, including
4018-486: Is usual with categorization, there are borderline cases; caffeine , for example, is considered a performance enhancer by some but not others. The phrase has been used to refer to several distinct classes of drugs: Anabolic steroids are synthetically derived from testosterone and modified to have greater anabolic effects. They work by increasing the concentration of nitrogen in the muscle which inhibits catabolic glucocorticoid binding to muscle. This ultimately prohibits
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4116-548: The Age of Enlightenment . He cites Francis Bacon (1561–1626) as an advocate of using science and reason to extend human life, noting Bacon's novel New Atlantis , wherein scientists worked toward delaying aging and prolonging life. Robert Boyle (1627–1691), founding member of the Royal Society , also hoped that science would make substantial progress with life extension, according to Hughes, and proposed such experiments as "to replace
4214-658: The Methuselah Foundation , which gives financial grants to anti-aging research projects. In 2009, de Grey and several others founded the SENS Research Foundation , a California-based scientific research organization which conducts research into aging and funds other anti-aging research projects at various universities. In 2013, Google announced Calico , a new company based in San Francisco that will harness new technologies to increase scientific understanding of
4312-645: The SASP . Senomorphic effects may be one major effect mechanism of a range of prolongevity drug candidates. Such candidates are however typically not studied for just one mechanism, but multiple. There are biological databases of prolongevity drug candidates under research as well as of potential gene/protein targets. These are enhanced by longitudinal cohort studies , electronic health records , computational (drug) screening methods, computational biomarker-discovery methods and computational biodata-interpretation/ personalized medicine methods. Besides rapamycin and senolytics,
4410-964: The World Anti-Doping Agency 's banned list. Nootropics, or "cognition enhancers", are substances that are claimed to benefit overall cognition by improving memory (e.g., increasing working memory capacity or updating) or other aspects of cognitive control (e.g., inhibitory control , attentional control , attention span , etc.). Allows performance beyond the usual pain threshold. Some painkillers raise blood pressure , increasing oxygen supply to muscle cells . Painkillers used by athletes range from common over-the-counter medicines such as NSAIDs (such as ibuprofen ) to powerful prescription narcotics . Sedatives and anxiolytics are used in sports like archery which require steady hands and accurate aim, and also to overcome excessive nervousness or discomfort for more dangerous sports. Diazepam , nicotine, and propranolol are common examples. Ethanol ,
4508-467: The adrenergic receptors . Examples of stimulants include caffeine , ephedrine , methylphenidate and amphetamine . Potential side effects include hypertension, insomnia , headaches , weight loss , arrhythmia , tremors , anxiety , addiction, and strokes . Some stimulants are allowed in competitive sports and are widely accessible, though may also be monitored by the World Anti-Doping Agency (WADA), such as caffeine. Others are banned as per
4606-1156: The drug-repurposing candidates studied most extensively include metformin , acarbose , spermidine and NAD+ enhancers. Performance-enhancing substances Many substances, such as anabolic steroids , can be used to improve athletic performance and build muscle, which in most cases is considered cheating by organized athletic organizations. This usage is often referred to as doping . Athletic performance-enhancing substances are sometimes referred to as ergogenic aids . Cognitive performance-enhancing drugs, commonly called nootropics , are sometimes used by students to improve academic performance. Performance-enhancing substances are also used by military personnel to enhance combat performance. The classifications of substances as performance-enhancing substances are not entirely clear-cut and objective. As in other types of categorization , certain prototype performance enhancers are universally classified as such (like anabolic steroids ), whereas other substances (like vitamins and protein supplements) are virtually never classified as performance enhancers despite their effects on performance. As
4704-660: The future . It is regarded with skepticism within the mainstream scientific community and has been characterized as quackery . Another proposed life extension technology aims to combine existing and predicted future biochemical and genetic techniques. SENS proposes that rejuvenation may be obtained by removing aging damage via the use of stem cells and tissue engineering , telomere -lengthening machinery, allotopic expression of mitochondrial proteins, targeted ablation of cells, immunotherapeutic clearance, and novel lysosomal hydrolases . While some biogerontologists find these ideas "worthy of discussion", others contend that
4802-556: The ventral dermis , allowing them to glide along on a film of mucus . Some also can move by undulations of the whole body by the contractions of muscles built into the body membrane. Triclads play an important role in watercourse ecosystems and are often very important as bio-indicators. Phylogenetic supertree after Sluys et al., 2009: Maricola Cavernicola Planariidae Kenkiidae Dendrocoelidae Dugesiidae Geoplanidae Linnaean ranks after Sluys et al. , 2009: Planarians are bilaterian flatworms that lack
4900-686: The International Space Station (ISS) – though regeneration of amputated worms as double-headed heteromorphosis is not a rare phenomenon unique to a microgravity environment. In contrast, two-headed planaria regenerates can be induced by exposing amputated fragments to electrical fields. Such exposure with opposite polarity can induce a planarian with 2 tails. Two-headed planaria regenerates can be induced by treating amputated fragments with pharmacological agents that alter levels of calcium, cyclic AMP, and protein kinase C activity in cells, as well as by genetic expression blocks (interference RNA) to
4998-587: The Nobel Prize winning biologist Elie Metchnikoff (1845-1916) -- the author of the cell theory of immunity and vice director of Institut Pasteur in Paris, and Charles-Édouard Brown-Séquard (1817-1894) -- the president of the French Biological Society and one of the founders of modern endocrinology. Sociologist James Hughes claims that science has been tied to a cultural narrative of conquering death since
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#17328838127875096-427: The U.S., sought to determine how microgravity and micro-geomagnetic fields would affect the growth and regeneration of planarian flatworms , Dugesia japonica . They discovered that one of the amputated fragments sent to space regenerated into a double-headed worm. The majority of such amputated worms (95%) did not do so, however. An amputated worm regenerated into a double-head creature after spending five weeks aboard
5194-483: The US President's Council on Bioethics from 2001 to 2005) has questioned whether potential exacerbation of overpopulation problems would make life extension unethical. He states his opposition to life extension with the words: "simply to covet a prolonged life span for ourselves is both a sign and a cause of our failure to open ourselves to procreation and to any higher purpose ... [The] desire to prolong youthfulness
5292-552: The United States of America, it would also increase the regulation of the anti-aging market by the Food and Drug Administration (FDA). Anti-aging now falls under the regulations for cosmetic medicine which are less tight than those for drugs. A senolytic (from the words senescence and -lytic , "destroying") is among a class of small molecules under basic research to determine if they can selectively induce death of senescent cells and improve health in humans. A goal of this research
5390-708: The WADA (e.g., cocaine , amphetamines , ephedrine, etc.). Ergogenic aids, or athletic performance-enhancing substances, include a number of drugs with various effects on physical performance. Drugs such as amphetamine and methylphenidate increase power output at constant levels of perceived exertion and delay the onset of fatigue, among other athletic-performance-enhancing effects; bupropion also increases power output at constant levels of perceived exertion, but only during short-term use. Adaptogens are plants that support health through nonspecific effects, neutralize various environmental and physical stressors while being relatively safe and free of side effects. As of 2008,
5488-488: The alleged benefits are too speculative given the current state of technology, referring to it as "fantasy rather than science". Genome editing , in which nucleic acid polymers are delivered as a drug and are either expressed as proteins, interfere with the expression of proteins, or correct genetic mutations, has been proposed as a future strategy to prevent aging. CRISPR/Cas9 edits genes by precisely cutting DNA and then harnessing natural DNA repair processes to modify
5586-476: The athletic trainers (e.g., strychnine tablets made of cocaine and brandy ). In the 20th century, testosterone was isolated and characterized by scientists. In 1941, the first record of synthesized testosterone use occurred when a horse was given testosterone which successfully improved its race performance. Sports trainers soon after began advocating for testosterone use. Images of bodybuilders with massive muscles began circulating which further perpetuated
5684-429: The beginning of the modern period in this endeavor can be traced to the end of the 19th – beginning of the 20th century, to the so-called " fin-de-siècle " (end of the century) period, denoted as an "end of an epoch" and characterized by the rise of scientific optimism and therapeutic activism, entailing the pursuit of life extension (or life-extensionism). Among the foremost researchers of life extension at this period were
5782-484: The biology of aging. It is led by Arthur D. Levinson , and its research team includes scientists such as Hal V. Barron , David Botstein , and Cynthia Kenyon . In 2014, biologist Craig Venter founded Human Longevity Inc., a company dedicated to scientific research to end aging through genomics and cell therapy. They received funding with the goal of compiling a comprehensive human genotype, microbiome, and phenotype database. Aside from private initiatives, aging research
5880-518: The blood of the old with the blood of the young". Biologist Alexis Carrel (1873–1944) was inspired by a belief in indefinite human lifespan that he developed after experimenting with cells , says Hughes. Regulatory and legal struggles between the Food and Drug Administration (FDA) and the Life Extension organization included seizure of merchandise and court action. In 1991, Saul Kent and Bill Faloon ,
5978-409: The body (e.g. most Geoplaninae ). Sometimes, those species with two eyes may present smaller accessory or supernumerary eyes. The subterranean triclads are often eyeless or blind. The body of the triclads is covered by a ciliated epidermis that contains rhabdites . Between the epidermis and the gastrodermis there is a parenchymatous tissue or mesenchyme . The planarian nervous systems consists of
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#17328838127876076-401: The body can alter the expression of genes that encode molecules that provide positional information. Therefore, the activities of neoblasts and muscle cells following injuries are essential for successful regeneration. Historically, planarians have been considered "immortal under the edge of a knife." Very small pieces of the planarian, estimated to be as little as 1/279th of the organism it
6174-409: The body, these precursors are converted to testosterone and increase endogenous testosterone. The desired effects of steroid precursors however, are often not seen as they do not bind well to androgen receptors . Examples of prohormones include norandrostendione , androstenediol , and dehydroepiandrosterone (DHEA) . These steroids have little desired effect compared to anabolic steroids, but have
6272-1006: The breakdown of muscle and preserves muscle mass. Examples of anabolic steroids include: oxandrolone , stanozolol and nandrolone . Anabolic steroids can be taken through a transdermal method, orally, or through injection. Injectable forms of the steroid are the most potent and long-lasting. In general, potential side effects include: muscle hypertrophy , acne , hypertension , elevated cholesterol , thrombosis , decreased high-density lipoproteins , altered libido , hepatic carcinoma , cholestasis , peliosis hepatitis , septic arthritis , Wilm's tumor , psychosis , aggression , addiction , and depression . Potential side effects specifically in males include: male pattern baldness , oligospermia , prostate hypertrophy , testicular atrophy , and prostate cancer . Potential side specifically in females include: hirsutism , uterine atrophy , amenorrhea , breast atrophy , and thickening of vocal cords (voice deepening). Urine samples are tested to determine
6370-418: The canonical Wnt/β-Catenin signalling pathway. In 1955, Robert Thompson and James V. McConnell conditioned planarian flatworms by pairing a bright light with an electric shock. After repeating this several times they took away the electric shock, and only exposed them to the bright light. The flatworms would react to the bright light as if they had been shocked. Thompson and McConnell found that if they cut
6468-410: The changes caused by these genes activating can be lethal. It is a statistical certainty that we possess more lethal genes that activate in later life than in early life. Therefore, to extend life, we should be able to prevent these genes from switching on, and we should be able to do so by "identifying changes in the internal chemical environment of a body that take place during aging... and by simulating
6566-464: The class Turbellaria , order Tricladida , which includes hundreds of species, found in freshwater, marine, and terrestrial habitats. Planarians are characterized by a three-branched intestine, including a single anterior and two posterior branches. Their body is populated by adult stem cells called neoblasts , which planarians use for regenerating missing body parts. Many species are able to regenerate any missing organ, which has made planarians
6664-477: The doctor ". The idea was incorporated into Feynman's 1959 essay There's Plenty of Room at the Bottom . Replacement of biological (susceptible to diseases) organs with mechanical ones could extend life. This is the goal of the 2045 Initiative . Cryonics is the low-temperature freezing (usually at −196 °C or −320.8 °F or 77.1 K) of a human corpse, with the hope that resuscitation may be possible in
6762-432: The effects of aging by 2030. According to Richard Feynman , it was his former graduate student and collaborator Albert Hibbs who originally suggested to him (circa 1959) the idea of a medical use for Feynman's theoretical nanomachines (see biological machine ). Hibbs suggested that certain repair machines might one day be reduced in size to the point that it would, in theory, be possible to (as Feynman put it) " swallow
6860-542: The enhancement of enzyme telomerase activity. Research geared towards life extension strategies in various organisms is currently under way at a number of academic and private institutions. Since 2009, investigators have found ways to increase the lifespan of nematode worms and yeast by 10-fold; the record in nematodes was achieved through genetic engineering and the extension in yeast by a combination of genetic engineering and caloric restriction . A 2009 review of longevity research noted: "Extrapolation from worms to mammals
6958-753: The fastest possible and at the same time soft transition of society to the next step – life without aging and with radical life extension, and to provide access to such technologies to most currently living people. Some tech innovators and Silicon Valley entrepreneurs have invested heavily into anti-aging research. This includes Jeff Bezos (founder of Amazon ), Larry Ellison (founder of Oracle ), Peter Thiel (former PayPal CEO), Larry Page (co-founder of Google ), Peter Diamandis , Sam Altman (CEO of OpenAI , invested in Retro Biosciences ), and Brian Armstrong (founder of Coinbase and NewLimit), Bryan Johnson (Founder of Kernel ). Leon Kass (chairman of
7056-812: The gene in the desired manner. The system has two components: the Cas9 enzyme and a guide RNA. A large array of genetic modifications have been found to increase lifespan in model organisms such as yeast, nematode worms, fruit flies, and mice. As of 2013, the longest extension of life caused by a single gene manipulation was roughly 50% in mice and 10-fold in nematode worms. In July 2020 scientists, using public biological data on 1.75 m people with known lifespans overall, identify 10 genomic loci which appear to intrinsically influence healthspan , lifespan, and longevity – of which half have not been reported previously at genome-wide significance and most being associated with cardiovascular disease – and identify haem metabolism as
7154-608: The growth of a new tissue. Neoblasts localized near the injury site proliferate to generate a structure of differentiating cells called blastema . Neoblasts are required for new cell production, and they therefore provide the cellular basis for planarian regeneration. Cell signaling mechanisms provide positional information that regulates the cell types and tissues that are produced from the neoblasts in regeneration. Many signaling molecules that provide positional information to neoblasts, in regeneration and homeostasis, are expressed in muscle cells. Following injury, muscle cells throughout
7252-573: The most common gendered risk factors include being an adolescent female dissatisfied with their body weight or an adolescent male who perceives larger body sizes as the ideal. Having a negative body image or a history of depression can also be a significant risk factor. These are further exacerbated by parental pressures surrounding appearance, media influence, and peer pressure. Studies show that adolescent males who engage with fitness magazines are twice as likely to use performance-enhancing substances. Adolescents who partake in competitive sports are at
7350-588: The most commonly used substance by athletes, can be used for cardiovascular improvements though has significant detrimental effects. Ethanol was formerly banned by WADA during performance for athletes performing in aeronautics, archery, automobile, karate, motorcycling and powerboating, but was taken off the ban list in 2017. It is detected by breath or blood testing . Cannabis is banned at all times for an athlete by WADA, though performance-enhancing effects have yet to be studied. Cannabis and nicotine are detected through urine analysis . Blood doping agents increase
7448-412: The next longest-lived primate. From an evolutionary perspective, mammals and their ancestors have already undergone several hundred million years of natural selection favoring traits that could directly or indirectly favor increased longevity, and may thus have already settled on gene sequences that promote lifespan. Moreover, the very notion of a "life-extension factor" that could apply across taxa presumes
7546-493: The other planarian, giving and receiving sperm . Eggs develop inside the body and are shed in capsules. Weeks later, the eggs hatch and grow into adults. In asexual reproduction, the planarian fissions and each fragment regenerates its missing tissues, generating complete anatomy and restoring functions. Asexual reproduction, similar to regeneration following injury, requires neoblasts , adult stem cells, which proliferate and produce differentiated cells. Some researchers claim that
7644-428: The oxygen-carrying capacity of blood beyond the individual's natural capacity. They are used in endurance sports like long-distance running, cycling, and Nordic skiing. Recombinant human erythropoietin (rhEPO) is one of the most widely known drugs in this class. The Athlete Biological Passport is the only indirect testing method for detection of blood doping. Erythropoietin, or EPO, is a hormone that helps increase
7742-745: The planarian parenchyma across the planarian body. They are small and round cells, 5 to 10 μm, and characterized by a large nucleus, which is surrounded by little cytoplasm. Neoblasts are required for regenerating missing tissues and organs, and they continuously replenish tissues by producing new cells. Neoblasts can self-renew and generate progenitors for different cell types. In contrast to adult vertebrate stem cells (e.g., hematopoietic stem cell ), neoblasts are pluripotent (i.e., producing all somatic cell types). Moreover, they give rise to differentiating, post-mitotic, cells directly, and not by producing rapidly-dividing transit amplifying cells . Consequently, neoblasts divide frequently, and apparently lack
7840-402: The planarian's body by diffusing through the body wall. Triclads reproduce sexually and asexually, and different species may be able to reproduce by one or both modes. Planarians are hermaphrodites . In sexual reproduction, the mating generally involves mutual insemination. Thus, one of their gametes will combine with the gamete of another planarian. Each planarian transports its secretion to
7938-536: The portrayal of aging as a disease. For example, Leonard Hayflick , who determined that fibroblasts are limited to around 50 cell divisions, reasons that aging is an unavoidable consequence of entropy . Hayflick and fellow biogerontologists Jay Olshansky and Bruce Carnes have strongly criticized the anti-aging industry in response to what they see as unscrupulous profiteering from the sale of unproven anti-aging supplements . Research by Sobh and Martin (2011) suggests that people buy anti-aging products to obtain
8036-917: The position of the European Medicines Agency was that "The principle of an adaptogenic action needs further clarification and studies in the pre-clinical and clinical area. As such, the term is not accepted in pharmacological and clinical terminology that is commonly used in the EU." Actoprotectors or synthetic adaptogens are compounds that enhance an organism's resilience to physical stress without increasing heat output. Actoprotectors are distinct from other doping compounds in that they increase physical and psychological resilience via non-exhaustive action. Actoprotectors such as bemethyl and bromantane have been used to prepare athletes and enhance performance in Olympic competition. However, only bromantane has been placed on
8134-420: The possibility of growing human body parts on mice. Complex biological structures, such as mammalian joints and limbs, have not yet been replicated. Dog and primate brain transplantation experiments were conducted in the mid-20th century but failed due to rejection and the inability to restore nerve connections. As of 2006, the implantation of bio-engineered bladders grown from patients' own cells has proven to be
8232-420: The potential role of embryonic stem cells in life extension. Other modern life extensionists include writer Gennady Stolyarov , who insists that death is "the enemy of us all, to be fought with medicine, science, and technology"; transhumanist philosopher Zoltan Istvan , who proposes that the "transhumanist must safeguard one's own existence above all else"; futurist George Dvorsky , who considers aging to be
8330-557: The principals of the organization, were jailed for four hours and were released on $ 850,000 bond each. After 11 years of legal battles, Kent and Faloon convinced the US Attorney's Office to dismiss all criminal indictments brought against them by the FDA. In 2003, Doubleday published "The Immortal Cell: One Scientist's Quest to Solve the Mystery of Human Aging," by Michael D. West . West emphasised
8428-407: The production of red blood cells which increases the delivery of oxygen to muscles. It is commonly used among endurance athletes such as cyclists. It functions by protecting red blood cells against destruction whilst simultaneously stimulating bone marrow cells to produce more red blood cells. Potential side effects include: dehydration and an increase in blood viscosity which could result in
8526-587: The products derived from bisecting a planarian are similar to the products of planarian asexual reproduction; however, debates about the nature of asexual reproduction in planarians and its effect on the population are ongoing. Some species of planarian are exclusively asexual, whereas some can reproduce both sexually and asexually. In most of the cases the sexual reproduction involve two individuals; auto fecundation has been rarely reported (e.g. in Cura foremanii ). Neoblasts are abundant adult stem cells that are found in
8624-840: The ratio of testosterone glucuronide to epitestosterone glucuronide, which should be 3:1. Any ratio of 4:1 or greater is considered a positive test. The 1988 Anti-Drug Abuse Act and 1990 Anabolic Steroid Act both deemed anabolic steroids as an illegal substance when not used for disease treatment. Stimulants improve focus and alertness. Low (therapeutic) doses of dopaminergic stimulants (e.g., reuptake inhibitors and releasing agents ) also promote mental and athletic performance, as cognitive enhancers and ergogenic aids respectively, by improving muscle strength and endurance while decreasing reaction time and fatigue. Stimulants are commonly used in lengthy exercises that require short bursts (e.g., tennis, team sports, etc.). Stimulants work by increasing catecholamine levels and agonistic activity at
8722-421: The relative simplicity of planarians facilitates experimental study. Planarians have a number of cell types, tissues and simple organs that are homologous to our own cells , tissues and organs . However, regeneration has attracted the most attention. Thomas Hunt Morgan was responsible for some of the first systematic studies (that still underpin modern research) before the advent of molecular biology as
8820-476: The repair of many processes thought to be responsible for aging. K. Eric Drexler , one of the founders of nanotechnology , postulated cell repair machines, including ones operating within cells and utilizing as yet hypothetical molecular computers , in his 1986 book Engines of Creation . Raymond Kurzweil , a futurist and transhumanist , stated in his book The Singularity Is Near that he believes that advanced medical nanorobotics could completely remedy
8918-529: The same side effects. Androstenedione in 2005 became classified as a controlled substance by WADA, however DHEA can still be obtained legally as an over-the-counter nutritional supplement. While the use of PEDs has expanded in recent times, the practice of using substances to improve performance has been around since the Ancient Olympic Games . In the Olympic Games of 668 BC, Charmis had consumed
9016-458: The superficial chemical properties of a young body". Some life extensionists suggest that therapeutic cloning and stem cell research could one day provide a way to generate cells, body parts, or even entire bodies (generally referred to as reproductive cloning ) that would be genetically identical to a prospective patient. In 2008, the US Department of Defense announced a program to research
9114-537: The untrained flatworms were only following tracks left on the dirty glassware rather than absorbing the memory of their fodder. In 2012, Tal Shomrat and Michael Levin have shown that planarians exhibit evidence of long-term memory retrieval after regenerating a new head. Several planarian species are commonly used for biological research. Popular experimental species are Schmidtea mediterranea , Schmidtea polychroa , and Dugesia japonica , which in addition to excellent regenerative abilities, are easy to culture in
9212-494: The worldwide population growth rate is slowing down and is projected to eventually stabilize and begin falling, superlongevity would be unlikely to contribute to overpopulation. A Spring 2013 Pew Research poll in the United States found that 38% of Americans would want life extension treatments, and 56% would reject it. However, it also found that 68% believed most people would want it and that only 4% consider an "ideal lifespan" to be more than 120 years. The median "ideal lifespan"
9310-509: The worm in two, and allowed both worms to regenerate each half would develop the light-shock reaction. In 1963, McConnell repeated the experiment, but instead of cutting the trained flatworms in two he ground them into small pieces and fed them to other flatworms. He reported that the flatworms learned to associate the bright light with a shock much faster than flatworms who had not been fed trained worms. This experiment intended to test whether memory could be transferred chemically. The experiment
9408-433: Was 91 years of age and the majority of the public (63%) viewed medical advances aimed at prolonging life as generally good. 41% of Americans believed that radical life extension (RLE) would be good for society, while 51% said they believed it would be bad for society. One possibility for why 56% of Americans claim they would reject life extension treatments may be due to the cultural perception that living longer would result in
9506-444: Was formed to address the escalating use of substances in sports, particularly after the 1998 doping scandal in cycling. Adolescents are the most vulnerable group when it comes to taking performance-enhancing substances. This is in part due to the significance placed on physical appearance by this age group as well as feelings of invincibility combined with a lack of knowledge surrounding long-term consequences. Studies have shown that
9604-657: Was repeated with mice, fish, and rats, but it always failed to produce the same results. The perceived explanation was that rather than memory being transferred to the other animals, it was the hormones in the ingested ground animals that changed the behavior. McConnell believed that this was evidence of a chemical basis for memory, which he identified as memory RNA . McConnell's results are now attributed to observer bias . No blinded experiment has ever reproduced his results of planarians scrunching when exposed to light. Subsequent explanations of this scrunching behaviour associated with cannibalism of trained planarian worms were that
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