For years, the thought of living forever has been the subject of fascination. For many of us, it conjures the image of old billionaires being cryogenically frozen, but instead of living forever, what about living healthier for longer?
A simple treatment to delay the ageing process and all the ailments that come with it could be available in as little as five to 12 years.
Dr Doug Wilson, an expert on the ageing process, said trials involving senolytics - a new area of anti-ageing medicine - have proved successful in animal subjects, such as mice living longer lives. While the upcoming human clinical trials may not stop the ageing process, he said, it is "certainly going to interfere with them".
The treatment involves a senolytic drug, a new drug which "interferes with what are called senescent cells, and most of the cells in our bodies turn over after a certain number of growth cycles and get replaced," he told TVNZ 1's Breakfast this morning.
"The senescent cells are kind of ornery - they reach the end of their working life, they stop functioning, and instead of allowing themselves to be digested and disposed of, they sit around, release factors and produce inflammation, so they may represent five or 10 or 15 per cent of the cells of a particular tissue, but they're all the ones that cause all the trouble.
"So in the last two or three years, people have been investigating what happens if you get rid of the senescent cells – and there are medications and chemicals that are around today – that appear selectively to knock them off."
Studies in mice showed that killing off the senescent cells resulted in significant improvements, he said.
Currently, there are medications or chemicals being used "for other purposes" which appear to be "selectively knocking off the senescent cells, and people are doing that and now they're trying clinical studies … and they seem to be getting some clinical improvement, but whether that’s going to translate into a broader extension remains to be seen".
Dr Wilson said, however, that it is currently unknown if we will live for longer, "but the mice do".
"The important aspect of this is there are other chemicals, other medications out there which are already being investigated for their impact on slowing down ageing, and the reason why slowing down ageing is important is we have a number of diseases that are closely associated with ageing – dementia, diabetes, heart stroke, cancer, Parkinson's disease – and the thought is if you can slow down the ageing process, can you benefit each of these diseases and turn them into something that can be now managed far better than before.
"If you can improve the healthspan of those folk by intervening – and if one drug will treat the multiple diseases – then that's a great outcome."
He added that there are negative and positive outcomes in people having longer healthspans.
"It may be that a number of these other drugs in use targeting different things, some senescent cells, and one drug is showing that you can improve the immunity against infections in older individuals – older people – and you can, in fact, boost their response to vaccination, and at the same time, if you can reduce their resistance to getting pneumonia, then you're improving their healthspan from that sort of perspective ... but the question we do have is a social question.
"Our demographics are changing so fast that it's almost unbelievable," he said. One extreme example is Japan, where the number of centenarians jumped from 120 in the early 1960s to 70,000 last year.
Dr Wilson said it wasn't just about taking a pill to knock off senescent cells to improve your healthspan, but to also having a healthy diet, exercising and having great relationships.
"All those things are important, because our ageing starts to plug in early on, so our cells are programmed, we age."
He said a person in their 30s is already "10 years past your peak for some things, like computer games … so already, parts of your physiology is starting to decay a little, so that means, in fact, all the activities you’ve suggested – before exercise, diet and all of that – do play a part, and the earlier you bring those things into play, the more likely you are to extend the healthspan".
He said people are afraid of ageing "because they lose control, they lose independence, and they lose relevance, and losing relevance becomes kind of tricky".
"The most powerful indicator or activity that can improve our long-term healthspan and outcome are personal relationships - social relationships are important but personal relationships between, say, a spouse or a partner or close friends – have greater impact in terms of feeling better, looking positive about life, feeling happier and having a better outcome.
"These social interventions – the psychological way we approach this – becomes very important."