Science / A mutated gene doubled the lifespan of fruit flies
By Paul Risser, E.P
fruit flies. The flies also maintained a higher standard of living
A mutation of a gene that has earned the strange nickname "I'm not dead yet" is able to double the lifespan of fruit flies. This new discovery may lead to the development of drugs with which people can prolong their lives, and perhaps even lose weight.
Researchers at the University of Connecticut Health Center found that the lifespan of fruit flies increased from an average of 37 days to 70 days when the gene was changed on a single chromosome. Some of the flies in the experiment lived 110 days. The same gene for long life also exists in humans, said Stephen Halfand, senior author of the study. According to him, this "constitutes a goal for future drug treatments, which can prolong life". In human life terms, a double lifespan is about 150 years.
According to Halfand, the gene mutation works by limiting the absorption of calories at the cellular level - in other words, the cells go on a diet. Halfand claims that this will enable the future development of a drug that can both extend life and control weight. "From what we know about this garden, it makes perfect sense," he said.
Halfand said that an important finding of the study, which appeared on Friday in the journal "Science", is that the fruit flies not only lived for a longer period, but also maintained a high standard of living. "This is not a pointless extension of life. This is an extension of a mature and active life, and in my opinion, there is a chance that it will be possible to postpone the beginning of the aging process."
Some life extension studies have shown that animals tend to lose stamina and energy during longer lives, but according to Halfand, the mutated flies "maintain a high standard of living during longer lives. Even when 80-90% of the normal flies are already dead, the condition of the mutated flies is still excellent."
According to Blanca Rogina, who co-authored the study with the elfand, the female flies whose genes were mutated were able to reproduce throughout their lives. They had the energy to carry out the complex courtship process of the fruit flies, and they laid up to 2000 eggs during their lifetime, compared to about 1300 eggs that the female flies are able to lay normally.
According to Halfand, the Garden of Long Life got its name from a comic line taken from a Monty Python movie - "I'm not dead yet", and in short, "Indy". The garden was named courtesy of one of the authors of the study, Robert Rynan. "Childish humor, like that of Monty Python, is very acceptable in academic circles," Halfand said.
Other studies have also discovered genes for long life in fruit flies and nematodes (capillary worms), while experiments done in mice have shown that restricting calories through a severe diet can cause a doubling of lifespan in some cases. However, Yober Werner, director of research at the National Institute of Aging, said that the discovery of the indi gene is more significant because this "may open up another way through which it will be possible to reach the same result that was achieved by restricting calories in mice and other creatures." According to him, it may be possible to develop a drug that suppresses metabolism in the same way as the indi gene, but such a drug, if developed, would be extensively tested on animals to make sure it is harmless.
"If the intention is to slow down the metabolism of humans, this study shows that there is a way to do it," Warner said. "It's completely theoretical right now, but it's definitely a possibility."
Halfand and his colleagues discovered the longevity gene by accident. According to him, they used fruit flies in another study, and found that the flies lived a much longer time than usual. They isolated the indi gene, and tested it in different species of fruit flies. In all cases, the gene extended life. However, according to Halfand, the researchers discovered that when the gene undergoes too many mutations, it shortens life, not lengthens it. The normal gene appears on two chromosomes of the fruit fly. If one of the genes undergoes a change, thereby reducing its strength, the flies extend their lives. If both genes are completely inactivated, the flies die at an earlier stage, possibly because they have starved.
"If we limit the garden a little, it's a big advantage," said Halfand. "However, if we create an animal that only has the mutated gene, it will live a shorter life than usual."
{Appeared in Haaretz newspaper, 19/12/2000}
Science>> Microscope
Research: Life expectancy in the West is getting longer
The maximum life expectancy of a person in the developed countries - will be extended. In a few years it will not be rare to meet healthy people, 110 years old.
This is according to a new study published by researchers from the University of California, Berkeley. The head of the research team, Prof. John Wilmoth said that the model he tested was made only in Sweden, but it actually serves as a representative model for all industrialized countries in the world.
The researchers noted that it is now clear that human lifespan is not a biological problem. It involves continuous improvements in the environmental conditions in which man lives, a higher level of sanitation, constant improvements in the level of health services and medical innovations.
In 1860 the oldest man in Sweden was 100 years old. In 1960 he was already 105 years old and this year - 108 years old.
In 1997, the death of the person who was crowned "the oldest in the Western world" was reported - it was a French woman named Jean Kalman. She was 122 years old at the time. The American researchers believe that today there are more people in the world who have already passed this "ceiling age". (Due to problems with accurate registration, the authors of the study do not consider data from Georgia and the Caucasus on people who are presented by the authorities there as 140 years old).
Prof. Wilmoth pointed out that until now it was common to think that there is an upper limit to a person's lifespan, because tissues and organs in the body wear out and wear out over the years. Now it may be necessary to introduce changes in the theory dealing with human lifespan, the American researcher emphasized.
