Rejuvenation is a medical discipline focused on the reversal of the aging process . 
Rejuvenation is distinct from life extension . Life extension strategies often study the causes of aging and try to oppose those causes in order to slow aging. Rejuvenation is the reversal of aging and thus requires a different strategy, namely repair of the damage that is associated with aging or replacement of damaged tissue with new tissue. Rejuvenation can be a way of life extension, but most life extension strategies do not involve rejuvenation.
Historical and cultural background
Various myths tell the stories about the quest for rejuvenation. It was Believed That magic gold action of a supernatural power can bring back the youth and mythical Many adventurers set out we journey to Do That, for Themselves, Their authority on gold Some That feels em.
An ancient Chinese emperor actually thought that it would be a rejuvenate him. This led to a myth among modern Chinese that Japan was founded by these people.
In some religions, people were to be rejuvenated after death prior to placing them in heaven .
The stories continued well into the 16th century. The Spanish explorer Juan Ponce de Leon led an expedition around the Caribbean Islands and into Florida to the Fountain of Youth . Led by the rumors, the expedition continues the search and many perished. The Fountain was nowhere to be found as locals of its exact location.
Since the emergence of philosophy , the wise and the self-proclaimed wizards are made to be of great importance to the secret of youth, both for themselves and for their noble patrons and sponsors . It was widely believed that some potions may restore the youth.
Another approach Commonly Cited Was Attempting to transfer the fuel of youth from young people to old. Some examples of this approach were sleeping with virgins or children (sometimes literally sleeping, not Necessarily having sex),  bathing in or drinking Their blood.
The quest for rejuvenation reached its height with alchemy . All around Europe, and beyond, have been looking for the Philosopher’s Stone , the mythical substance that, it was believed, could not only lead to life, but also prolong life and restore youth. Although the set goal was not achieved, the way to the scientific method and the medical advances of today.
Serge Abrahamovitch Voronoff was a French surgeon born in Russia who gained fame for his technique of grafting monkey testicle tissue on the testicles of men while working in France in the 1920s and 1930s. This was one of the first medically accepted rejuvenation therapies (before it was proved to be wrong around 1930-1940). The technique was a great deal of money, it was already independently wealthy. As his work fell out of favor, he went on to be a highly respected surgeon to a ridiculous subject. By the early 1930s, over 500 men had been treated in France by his technical rejuvenation, and thousands more around the world, such as in Algiers .  Noteworthy people who had the surgery includedHarold McCormick , chairman of the board of the International Harvester Company ,  and the aging prime of Turkey . 
Swiss doctor Paul Niehans , who was one of the fathers of cellular therapy, developed in 1931-1949 the so-called Fresh Cell Therapy. These cells are mainly used for the production of embryonic organs, which are injected into the patient’s body with the purpose of achieving a revitalizing effect. These cells are derived from sheep ‘s fetuses because of comparison to other animals, such as pigs, rabbits and cows, and are rarely infected. Of course animal cells are not able to be included in the human tissue, but they can be secrete factors for rejuvenating. That’s why this rejuvenation technology, despite the harsh criticism   is practiced to this day. 
In fiction, there is an increasing amount of work being done on the possibilities of rejuvenation treatments, and the effect this would have on society. Misspent Youth as well as the Commonwealth Saga by Peter F. Hamilton are one of the most famous examples of this, dealing with the short-and-long-term effects of a near-perfect 80-year-old to 20-year-old body change with mind intact. Also the March trilogy deals with a much more imperfect kind of rejuvenation, Including Such As problems long-term memory loss and sheer boredom That comes with Such age. Also the post-mortal characters in the Revelation Space series of this issue with infinespecially lifespans, sheer boredom induces them to engage in activities of extreme risk.
Aging is an accumulation of damage to macromolecules , cells , tissues and organs . If any of that damage can be repaired, the result is rejuvenation.
There have been many experiments which have been shown to increase the maximum life span of laboratory animals [ citation needed ] , thereby achieving life extension . A few experimental methods Such As Replacing hormones to youthful levels Have Had considerable success in rejuvenating Partially laboratory animals and humans. A recent experiment involves a genetically manipulated mice that lacked an enzyme called telomerase, which causes age and age. When the mice were given injections to reactivate the enzyme, it repaired the damaged tissues and reversed the signs of aging. There are at least eight important hormones that decline with age: 1. human growth hormone(HGH); 2. the sexual hormones: testosterone or estrogen / progesterone; 3. erythropoietin (EPO); 4. insulin; 5. DHEA ; 6. melatonin; 7. thyroid; 8. pregnenolone. In theory, if all of these hormones are replaced, the body will respond to it as it was younger, thus repairing and restoring many body functions. In line with this, recent experiments show that heterochronic parabiosis, ie, connecting the circulatory systems of young and old animals, leads to the rejuvenation of the old animal, including the restoration of proper stem cell function. Similar experiments show that the grafting of old muscles into young hosts leads to their complete restoration These experiments show that aging is mediated by a systemic environment, rather than being an intrinsic cell property [ citation needed ] . Clinical trials based on transfusion of young blood were scheduled to begin in 2014. 
Most attempts at genetic repair have traditionally involved the use of a retrovirus to insert a new gene into a chromosome . But by attaching zinc fingers (which determines where transcription factors bind) to endonucleases (which break DNA strands), homologous recombination can be induced to correct and replace defective (or undesired) DNA sequences. The first applications of this technology are to isolate stem cells from the bone marrow of patients having blood disease mutations, to correct these mutations in laboratory dishes using zinc finger endonucleases and to transplant the stem cells back into the patients. 
Stem cell regenerative medicine uses three different strategies:
- Implantation of stem cells from growing into an existing tissue structure
- Implantation of stem cells in a tissue scaffold that guides restoration
- Induction of residual cells of a tissue structure
A salamander can not only regenerate a limb , but can regenerate the lens or retina of an eye and can regenerate an intestine . For regeneration the salamander tissues form a blastema by de-differentiation of mesenchymal cells , and the blastema functions as a self-organizing system to regenerate the limb. 
Yet another option involves cosmetic changes to the individual to create the appearance of youth. These are the general characteristics of a person who lives with a positive attitude, but the improvement of their moods and their positive effects is usually correlated with happiness . The removal of extra fat (liposuction) and reshaping or augmentation of various body parts ( abdomen , breasts , face ).
There are many, as well, many years of experience that have been shown to be ineffective. Chief among these are powders, sprays, gels, and homeopathic substances that claim to contain growth hormones. Authentic growth hormones are only effective when injected, due to the fact that the 191-amino acid protein is too large to be absorbed through the mucous membranes , and would be broken up in the stomach if swallowed.
The Mprize scientific competition is under way to deliver on the mission of extending healthy human life. It directly accelerates the development of revolutionary new life extension therapies by awarding two cash prizes: one to the research team that breaks the world record for the oldest-ever mouse; and one to the team that develops the most successful late-onset rejuvenation. Current Mprize winner for rejuvenation is Steven Spindler. Caloric restriction (CR), the consumption of fewer calories while avoiding malnutrition, was applied as a robust method of decelerating aging and the development of age-related diseases. 
Strategies for Engineered Negligible Senescence
The Aubrey of Gray, a biomedical gerontologist, has initiated a project, Strategies for Engineered Negligible Senescence (SENS), to study how to reverse the damage caused by aging. He has proposed seven strategies for what he calls the seven deadly sins of aging: 
- Cell loss can be repaired (reversed) just by suitable exercise in the case of muscle . For other tissues it needs different growth factors to stimulate cell division , or in some cases it needs stem cells .
- Senescent cells can be removed by activating the immune system against them. But they can be destroyed by gene therapy to introduce “suicide genes ” that only kill senescent cells.
- Protein cross-linking can largely be reversed by drugs that break the links. But to break some of the cross-links we can need to develop enzymatic methods.
- Extracellular garbage (like amyloid ) can be eliminated by vaccination that gets immune cells to “eat” the garbage.
- For intracellular junk we need to introduce new enzymes , possibly enzymes from soil bacteria , that can degrade the junk ( lipofuscin ) that our own natural enzymes can not degrade.
- For mitochondrial mutations the plan is not to repair them but to prevent harm from the mutations by putting suitably modified copies of the mitochondrial genes into the cell nucleus by gene therapy. The mitochondrial DNAhas a high degree of mutagenic damage because it is most free radicals generated in the mitochondria . A copy of the mitochondrial DNA located in the nucleus will be better protected from free radicals, and there will be better DNA repair when damage occurs. All mitochondrial proteins would then be imported into the mitochondria.
- For cancer (The Most lethal consequence of mutations) the strategy is to use gene therapy to delete the gene for telomerase and telomerase-independent to Eliminate Mechanisms of turning normal cells into “immortal” cancer cells. To compensate for the loss of telomerase in stem cells we would introduce new stem cells every decade or so. 
In 2009, Aubrey de Gray co-founded the SENS Foundation to expedite progress in the above-listed areas.
- Rejuvenation Research Editor: Aubrey de Gray . Publisher: Mary Ann Liebert, Inc. ISSN 1549-1684 – Published Bimonthly.
- Aging brain
- American Academy of Anti-Aging Medicine
- Biological immortality
- DNA repair
- DNA damage theory of aging
- Eternal youth
- Facial rejuvenation
- Fountain of Youth
- Hayflick limit
- Indiafinite lifespan
- iPSc as a result of radical rejuvenation
- Life extension
- Maximum life span
- SAGE KE
- Timeline of senescence research
- Tissue engineering
- Therapeutic cloning
- Jump up^ From Gray, Aubrey DNJ (2004). “Welcome to Rejuvenation Research”. Rejuvenation Research . 7 : 1-2. doi : 10.1089 / 154916804323105017 .
- Jump up^ Shapin, Steven; Martyn, Christopher (23 December 2000). “How to live forever: lessons of history” . BMJ . 321 (7276): 1580-1582. doi : 10.1136 / bmj.321.7276.1580 . PMC 1119261 . PMID 11124187 – via www.bmj.com.
- Jump up^ Common, Laura. (April 25, 2000)The Medical Post  Great Balls of Fire: from prehistory, men-have tried implants and extracts from macho animals to cure impotence, aim It was only recently Relatively That They Began To Understand why They Did so.
- Jump up^ Grossman, Ron. (March 31, 1985)Chicago Tribune Lost lake shore drive: Mourning an era; Mansions of rich and famous yield to giant condos. Section: Real estate; Page 1.
- Jump up^ Jones, David. (December 11, 1986) The Times Christmas Books: Believe it or not – Adam and Eve to bent spoons / Review of books on beliefs.
- Jump up^ Chaisinthop, N. (2013). What is Fresh Cell Therapy?
- Jump up^ Robyn MP, AP Newman, Amato M., Walawander M., Kothe C., Nerone JD, Pieracci EG (2015). “Q Fever Outbreak Among Travelers to Germany Who Received Live Cell Therapy – United States and Canada, 2014” . MMWR Morb Mortal Weekly Rep . 64 (38): 1071-1073.
- Jump up^ “Dr. Janson-Müller: Hintergründe” .
- Jump up^ Jaskelioff, Mariela; Muller, Florian L .; et al. (2010). “Telomerase reactivation reverses tissue degeneration in aged telomerase-deficient mice” . Nature . 469 (7328): 102-6. Bibcode : 2011Natur.469..102J . doi :10.1038 / nature09603 . PMC 3057569 . PMID 21113150 .
- Jump up^ “Young blood to be used in ultimate rejuvenation trial” . New Scientist. August 20, 2014.
- Jump up^ Jocelyn Kaiser (2005). “Gene therapy.” Putting the fingers on gene repair. Science . 310 (5756): 1894-6. doi : 10.1126 / science.310.5756.1894 . PMID 16373552 .
- Jump up^ Brockes, JP; Kumar, A (2005). “Appendix regeneration in adult vertebrates and implications for regenerative medicine” . Science . 310 (5756): 1919-23. Bibcode : 2005Sci … 310.1919B . doi : 10.1126 / science.1115200 . PMID 16373567 .
- Jump up^ Dhahbi, JM; Kim, H.-J .; Mote, PL; Beaver, RJ; Spindler, SR (2004). “Temporal linkage between the phenotypic and genomic responses to caloric restriction” . Proceedings of the National Academy of Sciences . 101 (15): 5524-5529. Bibcode : 2004PNAS..101.5524D . doi : 10.1073 / pnas.0305300101 . PMC 397416 . PMID 15044709 .
- Jump up^ from Gray, Aubrey; Rae, Michael (September 2007). Ending Aging: The Rejuvenation Breakthroughs That Could Reverse Human Aging in Our Lifetime . New York, NY: St. Martin’s Press . p. 416. ISBN 0-312-36706-6 .
- Jump up^ “Top Discoveries in AntiAgeing” . www.fortheageless.com.