According to researchers at the University of Cambridge, cold water baths may prevent degenerative brain diseases such as dementia. For the first time, scientists have identified a special protein called “cold shock” in the blood of “walruses” swimming in the open pool at Hampstead Heath Park in London. This protein slows the development of dementia and, as experiments in mice have shown, is even able to regenerate nerve fibers damaged by the disease.
According to Professor Giovanna Mallucci, director of the Dementia Research Centre at the University of Cambridge, this discovery could lead to the creation of a new drug that could help prevent the development of Alzheimer’s disease. Scientists are primarily interested in the ability of almost all mammals to go into hibernation under the influence of reduced external temperature. In this state, all vital processes in the body slow down.
Despite significant progress, this research is still in its early stages. In the UK, more than 1 million people live with varying degrees of dementia, and by 2050 this number will have doubled. Currently, there is almost no effective treatment for this disease.
Doctors have long known that cooling a person’s body temperature in certain situations can protect the brain. People with brain injuries or before heart surgery are put into a state of suspended animation by lowering their body temperature. However, scientists have not understood why cold has such a protective effect. It turns out that this has to do with how synapses – the points of contact between nerve cells in the brain – form and collapse. In the early stages of Alzheimer’s disease and other neurodegenerative disorders, these neural connections are disrupted. This leads to a range of symptoms typical of dementia, including forgetfulness, confusion, sudden mood swings, and sometimes even the death of entire brain regions.
Professor Mallucci was particularly interested in the fact that such death of entire brain regions occurs in hibernating animals such as bears, hedgehogs, and bats. About 20-30% of their synapses seem to die as their body slows down all vital processes. However, they miraculously recover when these animals emerge from hibernation in the spring.
Cold has a very powerful effect on the human body. The shock of cold water immersion causes a rapid increase in heart rate and blood pressure, which can lead to heart attack or stroke in people with cardiovascular disease. This can also cause an attack of spasmodic breathing, and a person may eventually choke and drown. The more time a person spends in the water, the slower their reactions become. In such situations, people sometimes lose their agility, feel confused, and struggle to get to shore. Dr. Heather Massey, from the Laboratory for the Study of Extreme Conditions at the University of Portsmouth, says it’s important to remember a few basic rules. But, Dr. Macy warns, do not take a hot bath or shower. As you warm up, your blood pressure may drop sharply, causing you to faint.
In 2015, a team of Cambridge scientists discovered specific chemicals that accompany the cold shock the body experiences. During the experiment, they subjected normal healthy mice, as well as mice with Alzheimer’s disease and prion disease (also classified as neurodegenerative), to cooling until they reached a state of hypothermia – meaning the mice’s body temperature fell below 35 degrees Celsius. After the animals returned to normal, scientists discovered that only normal mice were able to restore all their neural connections, or synapses, while those with Alzheimer’s and prion disease were not. At the same time, they found that the amount of RBM3 protein produced by the organism experiencing “cold shock” increased sharply in healthy mice, but not in sick mice. This led to the assumption that the protein RBM3 might be responsible for the formation of new neural connections.
The author of the article, Justin Rowlett, tries ice swimming on himself. Scientists at the University of Cambridge have confirmed their discovery in another experiment showing that brain cell death in Alzheimer’s and prion diseases can be prevented by artificially increasing levels of the RBM3 protein in mice. This is a major breakthrough in dementia research. The scientists’ conclusions were published in the journal Nature. Now, Professor Mallucci believes that a drug capable of inducing the production of the protein RBM3 in the body could help slow down and possibly even partially cure the development of neurodegenerative diseases in humans.
Since the protein RBM3 has not been detected in a regular analysis of human blood, the logical step was to understand when exactly it appears, but in order to do this, the participants had to be subjected to hypothermia. For medical-ethical reasons, this was not so easy, as Professor Mallucci revealed in an interview with the national radio station BBC. That’s where Martin Pate, a swimmer in a small group of enthusiasts who like to swim in an outdoor pool in London’s Hampstead Heath Park in the winter, came to the rescue. He sent an email to the professor saying that he and several others like him would be willing to undergo hypothermia on a regular basis – for scientific purposes.
Professor Mallucchi agreed to this experiment, which lasted for three winters – from 2016 to 2018 – during which her team regularly measured the presence of the “cold shock” protein in the blood of the subjects. As a control group, the researchers took members of the tai chi club who practiced next to the pool but never swam in it during the winter. It turned out that many of the main group of swimmers had elevated levels of the RBM3 protein as their body temperature dropped to 34 degrees. At the same time, none of the Tai Chi group demonstrated the presence of the RBM3 protein, but they did not experience such severe hypothermia. The progress of the study, conducted by a group of winter swimmers, can be seen in a series of online lectures, but there is currently no scientific publication on the subject. In several other studies, scientists have also found high levels of the RBM3 protein, for example, in infants or patients who have had a stroke or heart attack and undergone artificial hypothermia.
According to Professor Mallucchi, all of this shows that humans, like hibernating mammals, can independently produce the “cold shock” protein. However, the risks of hypothermia outweigh the potential benefits, so swimming in cold water is definitely not a cure for dementia. The current challenge, she says, is to develop a drug that stimulates the production of this protein in the human body. More importantly, they need to make sure it actually helps delay the onset of dementia. As is well known, this is a disease of the elderly, so even a small delay in the development of this disease can have a colossal impact on the quality of life, both for the individual and for society as a whole. “If you slow down the development of dementia in the population as a whole, even for a few years, it will have a colossal impact on the economy and on health care,” Professor Mallucchi says.