In the 1950s, reports came out of the Soviet Union about an unusual experiment in which a dog's life was radically lengthened by putting it into an artificial sleep for three months.
The research was done by S.N. Braines (I have no idea what "S.N." stands for). I believe that he reported his results in a 1952 article titled, "Result of artificial sleep in a biological experiment," published in a Soviet journal. But I can't be sure because I can't find the text of the article.
The results he achieved sound unlikely to me.
Omaha World-Herald - Oct 17, 1958
Text from Main Street, U.S.S.R. (1959), by Irving R. Levine
Evidence is accumulating that castration can increase a man's odds of living longer.
Farmers have long known that castrated sheep live longer than non-castrated sheep. But researchers in New Zealand were recently able to demonstrate, on a molecular level, that castration slows the aging of DNA (in sheep).
The presumption is that what's true for sheep is also likely true for humans. And there's research to back this up. From a 2015 article on BBC.com:
Korean scientist Han-Nam Park recently analysed the detailed records of court life from the 19th Century, including information about 81 eunuchs whose testicles had been removed before puberty. His analyses revealed that the eunuchs lived for around 70 years – compared to an average of just 50 years among the other men in the court. Overall, they were 130 times more likely to celebrate their hundredth birthday than the average man living in Korea at the time. Even the kings – who were the most pampered people in the palace – did not come close.
Paul Di Filippo
Paul has been paid to put weird ideas into fictional form for over thirty years, in his career as a noted science fiction writer. He has recently begun blogging on many curious topics with three fellow writers at The Inferior 4+1.