Harvard scientists were surprised that they saw a dramatic reversal, not just a slowing down, of the ageing in mice. Now they believe they might be able to regenerate human organs
In mice, reactivating the enzyme telomerase led to the repair of damaged tissues and reversed the signs of ageing. Photograph: Robert F. Bukaty/AP
Scientists claim to be a step closer to reversing the ageing process after rejuvenating worn out organs in elderly mice. The experimental treatment developed by researchers at Harvard Medical School turned weak and feeble old mice into healthy animals by regenerating their aged bodies.
The surprise recovery of the animals has raised hopes among scientists that it may be possible to achieve a similar feat in humans – or at least to slow down the ageing process.
An anti-ageing therapy could have a dramatic impact on public health by reducing the burden of age-related health problems, such as dementia, stroke and heart disease, and prolonging the quality of life for an increasingly aged population.
“What we saw in these animals was not a slowing down or stabilisation of the ageing process. We saw a dramatic reversal – and that was unexpected,” said Ronald DePinho, who led the study, which was published in the journal Nature.
“This could lead to strategies that enhance the regenerative potential of organs as individuals age and so increase their quality of life. Whether it serves to increase longevity is a question we are not yet in a position to answer.”
The ageing process is poorly understood, but scientists know it is caused by many factors. Highly reactive particles called free radicals are made naturally in the body and cause damage to cells, while smoking, ultraviolet light and other environmental factors contribute to ageing.
The Harvard group focused on a process called telomere shortening. Most cells in the body contain 23 pairs of chromosomes, which carry our DNA. At the ends of each chromosome is a protective cap called a telomere. Each time a cell divides, the telomeres are snipped shorter, until eventually they stop working and the cell dies or goes into a suspended state called “senescence”. The process is behind much of the wear and tear associated with ageing.
At Harvard, they bred genetically manipulated mice that lacked an enzyme called telomerase that stops telomeres getting shorter. Without the enzyme, the mice aged prematurely and suffered ailments, including a poor sense of smell, smaller brain size, infertility and damaged intestines and spleens. But when DePinho gave the mice injections to reactivate the enzyme, it repaired the damaged tissues and reversed the signs of ageing.
“These were severely aged animals, but after a month of treatment they showed a substantial restoration, including the growth of new neurons in their brains,” said DePinho.
Repeating the trick in humans will be more difficult. Mice make telomerase throughout their lives, but the enzyme is switched off in adult humans, an evolutionary compromise that stops cells growing out of control and turning into cancer. Raising levels of telomerase in people might slow the ageing process, but it makes the risk of cancer soar.
DePinho said the treatment might be safe in humans if it were given periodically and only to younger people who do not have tiny clumps of cancer cells already living, unnoticed, in their bodies.
David Kipling, who studies ageing at Cardiff University, said: “The goal for human tissue ‘rejuvenation’ would be to remove senescent cells, or else compensate for the deleterious effects they have on tissues and organs. Although this is a fascinating study, it must be remembered that mice are not little men, particularly with regard to their telomeres, and it remains unclear whether a similar telomerase reactivation in adult humans would lead to the removal of senescent cells.”
Lynne Cox, a biochemist at Oxford University, said the study was “extremely important” and “provides proof of principle that short-term treatment to restore telomerase in adults already showing age-related tissue degeneration can rejuvenate aged tissues and restore physiological function.”
DePinho said none of Harvard’s mice developed cancer after the treatment. The team is now investigating whether it extends the lifespan of mice or enables them to live healthier lives into old age.
Tom Kirkwood, director of the Institute for Ageing and Health at Newcastle University, said: “The key question is what might this mean for human therapies against age-related diseases? While there is some evidence that telomere erosion contributes to age-associated human pathology, it is surely not the only, or even dominant, cause, as it appears to be in mice engineered to lack telomerase. Furthermore, there is the ever-present anxiety that telomerase reactivation is a hallmark of most human cancers.”
According to those idiots over at the Guardian, “Harvard scientists reverse the ageing process in mice – now for humans”. As if that were not miraculous enough, the Guardian also claims that “Now they believe they might be able to regenerate human organs”. Here at the Hub we would love nothing more than for this story to be true, but alas it is one of the hugest piles of sensationalist bullshit I have seen on the net in quite a while. The scientific research cited by the Guardian does not support these sensationalist claims and the Guardian knows this. But they don’t give a damn because sensationalism sells – big time! The Guardian knows that sloppy, idiotic bloggers and news organizations across the web will regurgitate anything they see without hardly the slightest attempt at fact checking. And hence this bogus story has been an enormous hit. The story already has more than 15,000 Facebook likes and this number is sure to grow. It has been picked up and rehashed as a legitimate scientific story by major news outlets, including the Wall Street Journal, Digg, Endgadget, Wired, and many more. Congratulations to the Guardian and the author of the story, Ian Sample – you have created a story that sells well, but your reputation is utter crap.
First let us take a brief look at the scientific research that Guardian correspondent Ian Sample claims will reverse aging and allow us to regenerate human organs. Scientists at Harvard genetically altered mice so that they lacked an enzyme, telomerase, that is responsible for maintaining proper telomeres. Telomeres are repeated sequences of DNA at the ends of our DNA that protect the DNA from damage. Without the ability to produce the telomerase enzyme, the mice had essentially nonfunctioning telomeres, leaving their DNA unprotected and prone to extensive damage and malfunction over time. To no one’s surprise, as these mice grew and lived out their lives within the laboratory their bodies quickly broke down. Their organs began to fail – they lost their sense of smell, they became infertile, they were weak. With the mice now in this degraded state (that we are lead to believe approximates aging), the Harvard researchers then proceeded to give the mice regular injections of the telomerase enzyme to see what would happen to them.
So what happened to the mice once their broken, dying bodies were finally given injections to activate the vital telomerase enzyme that they had thus far been denied? In what will be a surprise to nobody (except apparently the Harvard researchers and Ian Sample at the Guardian) the bodies of the mice stopped their decay. As if this were not miraculous enough, the bodies of the mice also seemed to regain some of their lost vitality and function now that their DNA was allowed to function properly. Isn’t that amazing?
Any reasonable person would quickly summarize this research as something like “take away a vital enzyme from an organism and it starts to decay, give the enzyme back to the organism and decay stops, allowing the natural process of repair and growth in the organism to proceed”. The research sheds some light on how crucial telomerase and telomeres are to the proper function of an organism, but unless you are an expert in that field this is a non-story. This research is a long, long way from leading to a reversal in aging. Unless, that is, you are Ian Sample working for the Guardian, in which case apparently you have just stumbled upon a fantastic piece of research that you can use to create a misleading and sensationalist story that will sell to mindless readers and bloggers.
I can’t figure out what is more ridiculous here. Is the Guardian story itself the most ridiculous thing, or is the fact that the story was blindly syndicated by thousands of news outlets and believed by millions of readers across the world even more ridiculous? Ian Sample and the Guardian must be laughing all the way to the bank with the traffic this story is generating for them. Readers will correctly point out that I am only aiding their little game by giving the story even more prominence and calling it out in this post. To that all I can say is that I can’t stop people from reading the Guardian’s BS, but at least I can do my part to show the world what complete crap it is. The Guardian has gained itself a hugely popular story, but at what cost to it’s reputation? Sadly, most people probably won’t even care. But I can hope.