DR MICHAEL MOSLEY: Could the poisons in an anemone hold the key to a new generation of drugs?
For centuries, healers have used poisons, toxins and deadly venoms, extracted from plants, snakes and creepy crawlies, to treat a range of illnesses.
And now, using new technology, scientists are exploring ever more exotic toxins in the search for better ways to combat health problems such as chronic pain, where our current arsenal of effective remedies is rapidly diminishing.
Indeed, for the millions of adults in the UK who suffer from chronic pain came the unwelcome news this week that long-term use of paracetamol may increase the risk of heart disease and strokes in people who have high blood pressure.
Paracetamol was thought to be safe for long-term use and particularly helpful when other painkillers, such as opioid drugs, have significant drawbacks.
But now, ironically enough, new medicines to combat pain and other chronic health conditions may emerge from research into dangerous venoms.
At least that seems to be the conclusion of Australian scientists who are investigating potential medical uses for one of its more poisonous inhabitants.
Potent sting: The Australian sea anemone
Australia is home to some of the most poisonous spiders and snakes on Earth, including the inland taipan, a snake that’s said to carry enough venom in a single bite to kill around 250,000 mice.
A nd it is not just on land, the seas around Australia are also teeming with venomous creatures. These include the box jellyfish and the stone fish, which can both kill you.
Then there is the venomous Australian sea anemone, which new research shows has a battery of 84 different toxins it can deliver via its watery tentacles, many of which have the potential to render a nasty and painful sting.
But there is also a big plus side to these venoms — the potential to turn them into life-saving drugs.
Peter Prentice, a researcher at the Queensland University of Technology in Brisbane, has a particular interest in venomous sea anemones because he believes understanding the ways their neurotoxins cause pain will lead to novel ways to treat it, by ‘reverse engineering’ the process.
‘The toxins in the acontia — the long, stinging thread used to ward off would-be predators that causes intense pain to marine animals as well as humans — could be a source of an ‘antidote’ to some types of chronic pain,’ he said.
There are certainly grounds for optimism because we already have a drug called ziconotide, approved for the management of severe chronic pain, which is a synthetic version of a protein isolated from the venom of a fish-hunting snail called Conus magus.
And unlike opiates, such as morphine, ziconotide does not seem to lead to addiction.
Apart from potential painkillers, the strange world of poisons has given us some even more remarkable medicines, as I discovered when I made a series, called Pus, Pain And Poison, about the origins of modern medicines.
One of the poisons, curare, turned out to be critical to the history of surgery. When I was young I remember reading stories about indigenous tribes in South America using arrows that had been dipped in this deadly poison for hunting.
Curare is derived from a South American plant and was said to be so dangerous that anyone nicked by an arrow dipped in it suffered an agonising death, involving bulging eyes and exploding bowels.
In fact, curare doesn’t poison you — what it does do is paralyse the nerves that supply your voluntary muscles, so you can’t run away.
But because it also effectively paralyses the respiratory muscles (they become relaxed), you suffocate, unless you can be kept alive long enough, by artificial respiration, for the poison to wear off. A drug that causes such profound muscle paralysis is indispensable for some forms of surgery.
New research shows the Australian sea anemone (pictured) has a battery of 84 different toxins it can deliver via its watery tentacles, many of which have the potential to render a nasty and painful sting
Before we had muscle relaxants such as curare, it was very hard to operate on the belly, chest or do eye surgery because the muscles would contract and get in the way.
The first person to demonstrate the potential of curare in the operating theatre was one of my favourite self-experimenters, Dr Frederick Prescott, a man so modest that when he died even his own family didn’t know what he had achieved. There are no memorials — but what he did was incredibly brave.
In 1946 Prescott, a research director at the Wellcome Institute, decided to put himself through one of the most terrifying experiences imaginable. He asked his colleagues to inject him with curare, then try to keep him alive with artificial respiration.
A flaw in his self-experiment was that he had failed to build in any means of communication — so when he started to experience breathing difficulties, he had no way of telling anyone.
H is colleagues were so busy watching their instruments that for a while they didn’t realise he was suffocating.
In a classic example of British understatement, he later said: ‘To be conscious yet paralysed and unable to breathe is a very unpleasant experience.’
Fortunately, he survived the experience and curare would go on to revolutionise surgery.
Modern technology means we can break down, study and create synthetic drugs in record time from even the tiniest amounts of toxins; and since many natural poisons and venoms target our nervous system, some of the likeliest medical advances will be in treating pain and neurological diseases.
Out in the wild are thousands of yet-to-be-studied species, including lots of snakes and sea anemones, producing complex venoms, which, in turn, are made up of dozens of different toxins.
I believe we have only scratched the surface of their potential and the future for venoms is golden.
I have a birthday coming up soon, but after reading about a recent study, I am hoping that no one will be wishing me a ‘happy birthday’ online.
That is because knowing someone’s birthday can be useful if you happen to be a hacker — because your date of birth is often used online by companies to check that they’re talking to the right person.
Computer scientists from the University of Edinburgh identified 18 million posts on Twitter over a 45-day period that mentioned the words ‘happy birthday’; 66,000 of those posts gave the name, birthday and age of the person whose birthday they were celebrating — so do think twice before sharing any of this personal information online.
I have a birthday coming up soon, but after reading about a recent study, I am hoping that no one will be wishing me a ‘happy birthday’ online (stock image)
Why do you like camping or going for long walks in the woods?
Is it because your parents instilled in you as a child a love of the great outdoors — or is it in large part because of the genes they passed on?
The answer, according to a recent UK study of identical twins, seems to be an almost equal mixture of both — meaning that genetics accounts for roughly 50 per cent of our tendency to love nature.
Spending time outdoors is great for our mental and physical health, but this is the first study to show genes play a role in whether we love camping!
The tiny forgotten heroes of the pandemic
There have been many heroes of the Covid pandemic — NHS staff, the scientists who developed life-saving vaccines and treatments — but I’d like to celebrate another, smaller, group of heroes who have kept us alive in the face of an implacable foe: our T-cells.
These cells are a part of our immune systems that rarely enjoyed the attention they deserved, but which have really stepped up to the mark in our long fight with Covid.
If you were vaccinated, or got Covid- 19 and were able to shrug it off, then you can thank your T-cells, which play a huge role in tracking down and killing invading microbes.
And as we have seen from a recent study in the journal Nature, they can also play a leading role in treating cancer.
I’d like to celebrate another, smaller, group of heroes who have kept us alive in the face of an implacable foe: our T-cells (stock image)
In 2010, three patients with chronic lymphocytic leukaemia, a blood cancer that is often fatal, were given an experimental treatment that involved removing T-cells from the patient’s blood and genetically engineering them to fight cancer, before they were infused back into the patient’s body.
What was really impressive was not only that in two out of the three patients the cancers vanished, but when these patients were tested again ten years after the treatment, scientists discovered that the genetically modified T-cells were still in the patients’ blood, ready to pounce if the cancer cells were to re-emerge.
One of those patients, Doug Olson, is now so healthy he has taken up distance running and completed six half marathons.
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