Our bodies work hard to keep everything in balance. Body temperature, fluid levels, and many chemical processes are carefully controlled every minute of the day.
This balanced state helps our organs function properly. When body temperature drops too low, however, serious problems can develop.
A core body temperature below 35 degrees Celsius is known as hypothermia. In this condition, the heart slows down, the brain becomes less active, and many organs begin to struggle. If hypothermia is severe and untreated, it can become life-threatening.
Even though hypothermia is an emergency, scientists have wondered whether some of its effects could actually be useful in medicine. Lower temperatures reduce the amount of energy the body needs to survive. This means cells consume less oxygen and produce less waste. Researchers have been interested in using this idea to protect the brain during a stroke.
Stroke is one of the leading causes of disability around the world. During an ischemic stroke, a blood clot blocks blood flow to part of the brain. Without oxygen, brain cells begin to die quickly.
Modern treatments can remove the clot and restore circulation, but many patients still experience lasting damage because the injured brain remains vulnerable even after blood flow returns.
A team of scientists investigated whether two older medicines, chlorpromazine and promethazine, could trigger a controlled cooling effect without the need for ice blankets or cooling machines. Their findings were published in Science Translational Medicine.
The researchers began by studying mice. They created a temporary blockage in a brain artery and then treated the animals with the drug combination.
The treatment lowered body temperature and reduced the amount of energy the animals were using. The mice also showed an interesting response. Instead of shivering to warm themselves, they remained calm and entered a state similar to hibernation.
This was an important finding because hibernation allows animals to survive periods of low energy use. In the treated mice, the drugs reduced the size of brain injuries and improved recovery of movement and neurological function.
The scientists then tested the approach in rhesus monkeys. Because monkeys are biologically closer to humans than mice, they provide a useful step before human studies. The drugs lowered the monkeys’ body temperatures to about 33 to 34 degrees Celsius.
Their metabolism also shifted. Instead of relying mostly on sugar for energy, their bodies used more fats and ketones. Scientists believe this change may help protect cells when oxygen supplies are limited.
The monkeys that received the treatment had much smaller brain injuries than those that did not receive it. These encouraging results suggested that the protective effects were not limited to mice.
The final part of the research involved people. Thirty-two stroke patients joined a Phase I clinical trial. Some participants received the medicines and others received a placebo. Different doses were tested to determine safety.
Doctors carefully watched for side effects such as low blood pressure, breathing difficulties, or dangerous changes in heart rate.
The treatment appeared safe and was generally well tolerated. Lower doses did not noticeably affect body temperature, but the 100-milligram dose produced a mild cooling effect and slowed the body’s metabolism. All of the patients who received this highest dose recovered well over the following 90 days.
The study raises an exciting possibility. Instead of fighting against the body’s response to cooling, doctors may one day intentionally use a controlled, temporary low-energy state to shield the brain from injury. If successful, this strategy could become an important addition to current stroke treatments.
At the same time, it is important not to overstate the findings. The human trial involved only a small number of patients, and larger studies are needed to determine whether the treatment truly improves long-term recovery.
Scientists still need to learn which patients benefit most, how quickly treatment should begin, and whether there are any risks that only become apparent in larger populations.
Even with these limitations, the study represents an important step forward. It combines ideas from emergency medicine, metabolism, and neuroscience to develop an entirely new way of protecting the brain.
If future studies confirm the early results, these common medicines could eventually help reduce the enormous burden that stroke places on patients, families, and healthcare systems around the world.
If you care about stroke, please read studies that diets high in flavonoids could help reduce stroke risk, and MIND diet could slow down cognitive decline after stroke.
For more health information, please see recent studies about antioxidants that could help reduce the risk of dementia, and tea and coffee may help lower your risk of stroke, dementia.
Source: Capital Medical University.
