do you have long-life genes?. There have been many recent advances to our longevity, Victoria Lambert gives old age a closer look.
'How incessant and great are the ills,” wrote CS Lewis, quoting Juvenal, “with which a prolonged old age is replete.” Yet given that he passed away at the age of 64, the writer would these days be counted as having died relatively young.
Since Lewis died in 1963, the definition of old age has changed – indeed, most of us today are not so much hoping for a long life, as expecting it. Researchers from the Aging Research Centre at the University of Southern Denmark claim that life expectancy will continue to rise indefinitely: half the children born in Britain in 2000 will live past 100, and half the babies born in Japan in 2007 will live to be 107.
This raises a host of questions. How will we cope with an older society? Is reaching old age in good enough condition to enjoy it a question of genes, diet or lifestyle? And will life expectancy continue to soar, or does the human body come with a built-in limit?
The answer to the second question, disappointingly for health freaks, seems to be genetics. Earlier this month, a team of scientists at Boston University claimed to be able to predict – with 77 per cent accuracy – which of us will live to 100. By studying the DNA of more than 1,000 people who have reached that age and comparing it with that of the general population, they found genetic signatures that appeared to confer “exceptional longevity”.
The researchers’ findings, published online in Science, seemed good news for anyone with those “signatures” – although their methods and conclusions have been criticised by other scientists, and they offered no insight into how common this set of genetic variants are, nor how an individual can be tested for them.
However, even if the study turns out to be accurate, those without the relevant genes need not despair. New findings from Japan suggest a startling way to extend your lifespan – if you’re a woman. Dr Noriko Kagawa, assistant director of the Kato Ladies Clinic in Tokyo, revealed at the European Society of Human Reproduction and Embryology in Rome two weeks ago that transplanting ovarian tissue into mice not only restored their fertility, but also extended the rodents’ lives by more than 40 per cent (to the equivalent of 120 in human years).
When Dr Kagawa transplanted minute slivers of tissue harvested from younger mice into older subjects, she was astonished to see that not only did the mice live longer, but they also became younger. “All the mice
that had received transplants resumed the normal reproductive behaviour of young mice,” she says.
But it wasn’t just that their menopause was reversed: “They showed interest in male mice, mated and had some pups. Normally, old mice stay in the corner of the cage and don’t move much, but these mice resumed quick movements. Their arthritis was cured.”
She noted, too, that the mice’s naturally thinning coats grew back thicker. In fact, the results were so surprising that she and her fellow researchers thought they had mixed up the tags on the animal cages, so youthful, healthy and frisky did the older mice become: “They were all over the male mice,” she says.
Applying this to humans might be a jump, but it’s eminently possible. “Women who have ovarian tissue frozen at a young age, perhaps because they are about to embark on cancer treatment, can have their young tissue transplanted back when they are older,” says Dr Kagawa. “Normally, we would be doing this to preserve their fertility or to expand their reproductive lifespan – but our mice experiment suggests that this might improve overall longevity.”
Dr Sherman Silber of St Luke’s Hospital in St Louis, Missouri, who pioneered the first ovarian transplant and has collaborated with Dr Kagawa and her team, is even more confident. “This is a genuine way for women to live longer,” he says. “There is a real human application to this discovery. Any woman – not just cancer patients – could benefit from having a piece of her ovary frozen at 20, not just to delay childbearing, but to extend her lifespan.”
The reason why the ovarian tissue has this effect seems to lie in the way that it stimulates the production of oestrogen. When women go through the menopause, their oestrogen levels fall dramatically, causing the symptoms – hot flushes, hair and libido loss, thinning bones, mood swings and poor skin – that are so well documented. In the animal world – and among primitive humans – females were programmed to die not long after menopause, as they were no longer needed genetically.
Thanks to modern medicine and better public health, women now live nearly as long after the menopause as before, yet their ovaries haven’t caught up with the jump in longevity. This means that the second half of their lives can be painful and often riven by infirmity. As Professor Bart Fauser, of the Utrecht Medical Centre in the Netherlands, explains, “Women were not meant to live without oestrogen for 40 to 50 years.”
As a result of the new research, Dr Silber believes that, in the short term, women should reconsider hormone replacement therapy: “Don’t wait until you’re 55 and in the middle of it; the damage to your body is done by then. You should be getting oestrogen at 45 before you start feeling symptoms.” He can also see young women in the future freezing a slice of ovarian tissue the size of a fingernail, removed in a quick keyhole procedure, to have it transplanted back in when they hit the menopause, and perhaps again at 60.
Even for those who have passed this point, he does not rule out transplants from daughters or nieces. “You’d need to be closely matched by tissue-typing, but then it would only take a little immune-suppression medication to prevent rejection; we’re getting better at that.”
This raises the startling prospect of our creating a generation of “super-cougars” – women who never age, while their peer group of men drop like flies. Yet Dr Silber has hope for his sex, too. “Urologists are increasingly thinking that all men need testosterone replacement,” he says – production of the hormone also slows down with ageing.
For those reluctant to explore surgical techniques, research from the Washington University School of Medicine in St Louis shows calorie restriction can also extend lifespan. In April, scientists reported that cutting calorie intake by between 10 and 50 per cent considerably increases longevity in animals, and leads to fewer problems with conditions related to ageing, such as cancer and cardiovascular disease. For men who wanted to keep up with their oestrogen-boosted wives, refusing dessert would be a good place to start.
“People will say it is not natural to live to 100,” says Dr Silber, “but then it’s not natural to survive cancer either. You don’t hear anyone complaining about that.”
Then again, as Juvenal pointed out centuries ago, old age is only desirable if it is healthy. Do we want to receive ovarian tissue transplants and live to 120, only to spend the final years in dramatically crumbling health?
Fortunately, the experience of the Japanese mice suggests that this won’t happen.
Dr Kagawa noted that the effects of the transplant wore off slowly, and the mice experienced a normal second menopause before they died. She does, however, think that 120 is about the maximum number of years that the rest of the human body can bear before wearing out. Just to be sure, though, she is now considering consecutive transplants in mice, in order to test the miraculous rejuvenating powers of the ovary to their limits. ( telegraph.co.uk )
'How incessant and great are the ills,” wrote CS Lewis, quoting Juvenal, “with which a prolonged old age is replete.” Yet given that he passed away at the age of 64, the writer would these days be counted as having died relatively young.
Since Lewis died in 1963, the definition of old age has changed – indeed, most of us today are not so much hoping for a long life, as expecting it. Researchers from the Aging Research Centre at the University of Southern Denmark claim that life expectancy will continue to rise indefinitely: half the children born in Britain in 2000 will live past 100, and half the babies born in Japan in 2007 will live to be 107.
This raises a host of questions. How will we cope with an older society? Is reaching old age in good enough condition to enjoy it a question of genes, diet or lifestyle? And will life expectancy continue to soar, or does the human body come with a built-in limit?
The answer to the second question, disappointingly for health freaks, seems to be genetics. Earlier this month, a team of scientists at Boston University claimed to be able to predict – with 77 per cent accuracy – which of us will live to 100. By studying the DNA of more than 1,000 people who have reached that age and comparing it with that of the general population, they found genetic signatures that appeared to confer “exceptional longevity”.
The researchers’ findings, published online in Science, seemed good news for anyone with those “signatures” – although their methods and conclusions have been criticised by other scientists, and they offered no insight into how common this set of genetic variants are, nor how an individual can be tested for them.
However, even if the study turns out to be accurate, those without the relevant genes need not despair. New findings from Japan suggest a startling way to extend your lifespan – if you’re a woman. Dr Noriko Kagawa, assistant director of the Kato Ladies Clinic in Tokyo, revealed at the European Society of Human Reproduction and Embryology in Rome two weeks ago that transplanting ovarian tissue into mice not only restored their fertility, but also extended the rodents’ lives by more than 40 per cent (to the equivalent of 120 in human years).
When Dr Kagawa transplanted minute slivers of tissue harvested from younger mice into older subjects, she was astonished to see that not only did the mice live longer, but they also became younger. “All the mice
that had received transplants resumed the normal reproductive behaviour of young mice,” she says.
But it wasn’t just that their menopause was reversed: “They showed interest in male mice, mated and had some pups. Normally, old mice stay in the corner of the cage and don’t move much, but these mice resumed quick movements. Their arthritis was cured.”
She noted, too, that the mice’s naturally thinning coats grew back thicker. In fact, the results were so surprising that she and her fellow researchers thought they had mixed up the tags on the animal cages, so youthful, healthy and frisky did the older mice become: “They were all over the male mice,” she says.
Applying this to humans might be a jump, but it’s eminently possible. “Women who have ovarian tissue frozen at a young age, perhaps because they are about to embark on cancer treatment, can have their young tissue transplanted back when they are older,” says Dr Kagawa. “Normally, we would be doing this to preserve their fertility or to expand their reproductive lifespan – but our mice experiment suggests that this might improve overall longevity.”
Dr Sherman Silber of St Luke’s Hospital in St Louis, Missouri, who pioneered the first ovarian transplant and has collaborated with Dr Kagawa and her team, is even more confident. “This is a genuine way for women to live longer,” he says. “There is a real human application to this discovery. Any woman – not just cancer patients – could benefit from having a piece of her ovary frozen at 20, not just to delay childbearing, but to extend her lifespan.”
The reason why the ovarian tissue has this effect seems to lie in the way that it stimulates the production of oestrogen. When women go through the menopause, their oestrogen levels fall dramatically, causing the symptoms – hot flushes, hair and libido loss, thinning bones, mood swings and poor skin – that are so well documented. In the animal world – and among primitive humans – females were programmed to die not long after menopause, as they were no longer needed genetically.
Thanks to modern medicine and better public health, women now live nearly as long after the menopause as before, yet their ovaries haven’t caught up with the jump in longevity. This means that the second half of their lives can be painful and often riven by infirmity. As Professor Bart Fauser, of the Utrecht Medical Centre in the Netherlands, explains, “Women were not meant to live without oestrogen for 40 to 50 years.”
As a result of the new research, Dr Silber believes that, in the short term, women should reconsider hormone replacement therapy: “Don’t wait until you’re 55 and in the middle of it; the damage to your body is done by then. You should be getting oestrogen at 45 before you start feeling symptoms.” He can also see young women in the future freezing a slice of ovarian tissue the size of a fingernail, removed in a quick keyhole procedure, to have it transplanted back in when they hit the menopause, and perhaps again at 60.
Even for those who have passed this point, he does not rule out transplants from daughters or nieces. “You’d need to be closely matched by tissue-typing, but then it would only take a little immune-suppression medication to prevent rejection; we’re getting better at that.”
This raises the startling prospect of our creating a generation of “super-cougars” – women who never age, while their peer group of men drop like flies. Yet Dr Silber has hope for his sex, too. “Urologists are increasingly thinking that all men need testosterone replacement,” he says – production of the hormone also slows down with ageing.
For those reluctant to explore surgical techniques, research from the Washington University School of Medicine in St Louis shows calorie restriction can also extend lifespan. In April, scientists reported that cutting calorie intake by between 10 and 50 per cent considerably increases longevity in animals, and leads to fewer problems with conditions related to ageing, such as cancer and cardiovascular disease. For men who wanted to keep up with their oestrogen-boosted wives, refusing dessert would be a good place to start.
“People will say it is not natural to live to 100,” says Dr Silber, “but then it’s not natural to survive cancer either. You don’t hear anyone complaining about that.”
Then again, as Juvenal pointed out centuries ago, old age is only desirable if it is healthy. Do we want to receive ovarian tissue transplants and live to 120, only to spend the final years in dramatically crumbling health?
Fortunately, the experience of the Japanese mice suggests that this won’t happen.
Dr Kagawa noted that the effects of the transplant wore off slowly, and the mice experienced a normal second menopause before they died. She does, however, think that 120 is about the maximum number of years that the rest of the human body can bear before wearing out. Just to be sure, though, she is now considering consecutive transplants in mice, in order to test the miraculous rejuvenating powers of the ovary to their limits. ( telegraph.co.uk )
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