A drug named PLX5622 can treat brain damage from cosmic radiations.

Humans are searching for an alternate habitat in the universe as Earth is becoming more and more hostile towards us. A lot of efforts are being made to colonize Mars and the passion of people like Elon Musk is commendable in this regard. His space agency, SpaceX, is working in collaboration with NASA to send humans to the red planet as soon as possible. He seems pretty determined to achieve this feat but he will have to overcome a handful of challenges before sending a manned mission to the depths of space. One of the most obvious and dangerous risks attached to such a flight is the attack of the cosmic radiations. The latest report suggests a massive boost to Musk’s mission as it says that a damaged brain caused by exposure to cosmic radiations can be treated.

Susanna Rosi, the Director of Neurocognitive Research in the UCSF Brain and Spinal Injury Center, has manufactured a drug that prevents memory impairment. According to a study that was published in ‘Scientific Journals’ on 18^th May 2018, they tested it on mice which were exposed to simulated space radiation. The results of their experiment were positive as the brain cells of those mice recovered.

This is an essential development for space ventures of humans as the levels of cosmic radiations increase exponentially once we leave the protective shield of Earth’s magnetic field. According to an estimate, these rays are 1000 times stronger in space than the International Space Station, which lies in the lower orbit of the Earth. If we want to colonize Mars, the protection of astronauts should be our top priority.

The mice were exposed for a day to a dose of radiation, comparable to what astronauts might experience in deep space, at NASA Space Radiation Laboratory in New York. This is a special experiment which needed specific conditions which could be met only by this lab in the United States. After this test, the mice were shifted back to UCSF. Some of them received a treatment for 15 days as they were given a drug, PLX5622, which was produced by Plexxikon, Inc.

The team of Rosi is trying to examine the impact of cosmic rays on the brains of deep space astronauts for the past 4 years. One of their prior experiments found that simulated space radiations cause anxiety and memory problems in mice. It was also observed that their microglia cells are activated when they are exposed to such rays. This leads to brain inflammation which is similar to the one we observe in case of neurodegenerative disorders like Alzheimer’s disease. Lastly, cosmic rays badly affect synapses. Rosi used this information as evidence and showed the dangers of these rays to the world by saying,

“We are starting to have evidence that exposure to deep space radiation might affect brain function over the long term, but as far as I know, no one had explored any possible countermeasures that might protect astronauts’ brains against this level of radiation exposure.”

According to a previous research of Rosi, PLX5622 hinders cognitive deficits in cancer radiation therapy of mice if it is administered before the irradiation of the brain. That information was used as a base to perform this experiment. Generally, when mice are placed in a room with a familiar and an unfamiliar object, they spend most of their time in analyzing the unknown body. The mice that were exposed to radiations three months earlier and were not treated spent equal time in examining both the objects. The researchers concluded that it was due to the memory impairment as the mice didn’t remember the object they saw the last day. On the other hand, those mice that were given PLX5622 showed proper mental health as they performed regularly in the memory test.

A detailed examination was performed on the brains of these animals which revealed that the count of activated microglia was much more in the untreated mice. Similarly, they lost a significant number of synapses. Contrary to that, the brains of the treated animals were absolutely normal. The scientists concluded that this drug replaces activated microglia to avoid cognitive deficiencies. Rosi concluded that in the following words:

“This is really neat evidence, first that rebooting the brain’s microglia can protect cognitive function following radiation exposure, and second that we don’t necessarily need to treat immediately following the radiation exposure for the drug to be effective.”