Australian and US scientists reverse ageing in mice, humans could be next.


Laboratory mouse
PhotoAgeing process reversed: It works in mice, now humans could be nextReuters

Australian and US researchers have developed a compound which reverses muscle ageing in mice, saying it could be one of the keys to reversing ageing in humans.

When used in trials, the compound gave mice more energy, toned their muscles, reduced inflammation, and led to big improvements in insulin resistance.

Scientists say it actually reversed the ageing process, not just slowing it down, and say that for humans the effect would be similar to a 60-year-old feeling like a 20-year-old.

And they say human trials could start within the year.

The study has been published this morning in the research journal Cell.

“I’ve been studying ageing at the molecular level now for nearly 20 years and I didn’t think I’d see a day when ageing could be reversed. I thought we’d be lucky to slow it down a little bit,” University of New South Wales geneticist Professor David Sinclair said.

“The mice had more energy, their muscles were as though they’d be exercising and it was able to mimic the benefits of diet and exercise just within a week.”

Video 4:39 Dr Nigel Turner from the University of NSW explains the research

Researchers reverse symptoms of aging with 1 week of treatment ABC News

Professor Sinclair led the study from his base at Harvard Medical School in the US.

“We think that should be able to keep people healthier for longer and keep them from getting diseases of ageing,” he said.

The researchers also looked at particular diseases in the old mice.

“We looked at diabetes, we looked at muscle wasting or frailty, and we also look at inflammations as something that gives rise to many diseases like arthritis. All of those aspects of ageing were reversed within that week and that was really quite a striking result,” Professor Sinclair said.

He said the team identified a new cause of ageing that is particularly prevalent in muscle, including the heart.

Audio 3:32 Researchers discover how to wind back the clock on ageing

AM

“What we think is going on is that we have two major chromosome sets in our body,” he said.

“We have chromosomes that we all know about, we call it our genome, but there’s other DNA that we often don’t think about – the mitochondrial DNA that we get from our mothers.

“What we found is that during ageing these two genomes, the chromosomes, don’t talk to each other,” he said.

“Much like a married couple talks to each other when they’re newly married but then they stop communicating after about 20 years, at least in some cases.

I’ve been studying ageing at the molecular level now for nearly 20 years and I didn’t think I’d see a day when ageing could be reversed.

Professor David Sinclair

“Then we found that we could reverse that and get the communication going again and the animals went back to being young again.

“We used a molecule that raises a chemical in the body that goes down as we get older – its simple name is NAD (Nicotinamide adenine dinucleotide),” he added.

“When we’re young we have the high levels of NAD and if we exercise and diet, the levels of this NAD molecule are high in our body.

“But as we get older, and as these mice in our experiments got older, the levels went down about 50 per cent and then we could give this drug to bring the levels back up again.”

The next stage in the research involves trials with humans, most likely within the next year.

Professor Sinclair is reluctant to forecast how long it will be before the compound might be readily available for use but he says he has established a company to push things along.

“These trials, if we do manage to do them in patients, are millions of dollars and really I need to raise money to be able to do them and that’s the mechanism,” he said.

Pesticides may harm growing brains


Two neonicotinoid chemicals may affect the developing nervous system in humans, according to the EU.

The European Food Safety Authority (EFSA) proposed that safe levels for exposure be lowered while further research is carried out.

They based their decision on studies that showed the chemicals had an impact on the brains of newborn rats.

bees

One of the pesticides was banned in the EU last April amid concerns over its impact on bee populations.

Neonicotinoids are “systemic” pesticides that make every part of a plant toxic to predators.

They have become very popular across the world over the past two decades as they are considered less harmful to humans and the environment than older chemicals.

But a growing number of research papers have linked the use of these nicotine-like pesticides to a rapid fall in bee numbers.

New levels needed

In April, the European Union introduced a two year moratorium on the use of several types of these chemicals, despite opposition from the UK.

Now EFSA, in a statement, says that it has concerns that two types of neonicotinoids, imidacloprid and acetamiprid, may “affect the developing human nervous system“.

They have proposed that guidance levels for acceptable exposure be lowered while further research is carried out.

The decision has been based on a review of research carried out in rats.

In one study, young rodents exposed to imidacloprid suffered brain shrinkage, weight loss and reduced movement.

In the statement, EFSA said that the two neonicotinoids may “adversely affect the development of neurons and brain structures associated with functions such as learning and memory”.

Current guidelines, it went on, “may not be protective enough to protect against developmental neurotoxicity and should be reduced”.

According to EU Commission health spokesman Frederic Vincent, they would now allow the chemical companies involved to comment on the findings.

“In principle, the next step would then be to amend the reference values,” he said, indicating that this would begin next March.

In their findings, EFSA pointed out that the available evidence had limitations but that they believed the health concerns that have been raised are legitimate.

But other experts said the move by EFSA was more of a precaution than anything else.

“The reduction in the reference values in most cases was modest,” said Prof Alan Boobis, from Imperial College London.

“Whilst there is clearly a question mark over the possible effects of these compounds on the developing brain, the conclusions of EFSA do not suggest that exposure of humans to these compounds at the levels that occur normally in food or in the environment is a cause for concern.